☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes☐ ☒ No ☒☐

Indicate by check mark whether the registrant has submitted electronically ~~and posted on its corporate Web site, if any,~~ every Interactive Data File required to be submitted ~~and posted~~ pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit ~~and post~~ such files). Yes☒ No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒

As of ~~May 31, 2018,~~November 8, 2023, the registrant had ~~42,313,552~~14,620,671 shares of common stock ~~$0.0001 par value per share,~~ outstanding.

(1) The balance sheet as of December 31, 2022 is derived from the audited financial statements as of that date.

(2) The Company effected a reverse stock split of its outstanding shares of common stock on October 19, 2022 where every ten shares of its common stock issued and outstanding was converted into one share of common stock. Any fractional post-split shares as a result of the reverse split were rounded down to the nearest whole post-split share. Shareholders of the Company previously authorized the Board of Directors to approve a reverse stock split at the annual meeting on October 18, 2022. All share amounts and per share amounts disclosed in this Quarterly Report on Form 10-Q have been restated to reflect the reverse stock split on a retroactive basis in all periods presented.

March 31,
2018

December 31,
2017

(Unaudited)

Assets

Current assets:

Cash and cash equivalents

$
62,754

$
7,298

Contribution receivable

—

1,382

Short-term marketable securities

71,281

79,212

Deferred offering costs

1,707

—

Prepaid expenses and other current assets

697

988

Total current assets

136,439

88,880

Property and equipment, net

6,591

6,958

Long-term marketable securities

—

5,118

Restricted cash

550

550

Other long-term assets

522

518

Total assets

$
144,102

$
102,024

Liabilities, Convertible Preferred Stock, and Stockholders’ (Deficit) Equity

Current liabilities:

Accounts payable

$
5,037

$
2,378

Accrued compensation

958

2,181

Accrued and other current liabilities

4,668

3,338

Total current liabilities

10,663

7,897

Deferred rent, net of current portion

3,062

3,166

Other non-current liabilities

101

118

Total liabilities

13,826

11,181

Commitments and contingencies (Note 6)

Convertible preferred stock, $0.0001 par value; 103,283,818 and 91,739,149 shares
   authorized as of March 31, 2018 and December 31, 2017, respectively; 31,750,297
   and 28,159,724 shares issued and outstanding as of March 31, 2018 and
   December 31, 2017, respectively; aggregate liquidation preference of $245,825 as of
   March 31, 2018 and $190,825 as of December 31, 2017, respectively

228,907

173,956

Stockholders’ deficit:

Common stock, $0.0001 par value; 140,000,000 and 122,000,000 shares
   authorized as of March 31, 2018 and December 31, 2017, respectively;
   5,230,976 and 4,830,389 shares issued and outstanding as of March 31,
   2018 and December 31, 2017, respectively

1

1

Additional paid-in capital

5,511

4,072

Related party promissory notes for purchase of common stock

(592
)

(202
)
Employee promissory notes for purchase of common stock

(400
)

—

Accumulated other comprehensive loss

(138
)

(104
)
Accumulated deficit

(103,013
)

(86,880
)
Total stockholders’ deficit

(98,631
)

(83,113
)
Total liabilities, convertible preferred stock, and stockholders’ deficit

$
144,102

$
102,024

(1) The Company effected a reverse stock split of its outstanding shares of common stock on October 19, 2022 where every ten shares of its common stock issued and outstanding was converted into one share of common stock. Any fractional post-split shares as a result of the reverse split were rounded down to the nearest whole post-split share. Shareholders of the Company previously authorized the Board of Directors to approve a reverse stock split at the annual meeting on October 18, 2022. All share amounts and per share amounts disclosed in this Quarterly Report on Form 10-Q have been restated to reflect the reverse stock split on a retroactive basis in all periods presented.

Condensed Statements of ~~Operations and Comprehensive Loss~~Stockholders’ Equity

(1) The Company effected a reverse stock split of its outstanding shares of common stock on October 19, 2022 where every ten shares of its common stock issued and outstanding was converted into one share of common stock. Any fractional post-split shares as a result of the reverse split were rounded down to the nearest whole post-split share. Shareholders of the Company previously authorized the Board of Directors to approve a reverse stock split at the annual meeting on October 18, 2022. All share amounts and per share ~~amounts)~~amounts disclosed in this Quarterly Report on Form 10-Q have been restated to reflect the reverse stock split on a retroactive basis in all periods presented.


	Three Months Ended March 31,						Nine Months Ended September 30,
	2018			2017			2023			2022
Operating activities
Net loss	$	(16,133	)	$	(8,934	)	$	(38,362	)	$	(45,758	)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization		502			94			951			1,771
Amortization of premium and discounts on marketable securities		(33	)		13
Amortization of debt issuance costs								705			989
Debt extinguishment loss upon paydown of principal								491			—
Debt extinguishment gain upon conversion to equity								—			(199	)
Net accretion and amortization of premium and discounts on marketable securities								(1,199	)		155
Gain on disposal of property and equipment								—			(247	)
Stock-based compensation		1,370			413			6,686			7,120
Accretion of tenant improvement allowance		(152	)		(151	)
Non-cash rent expense								(811	)		(1,891	)
Impairment of long-lived assets								5,602			—
Changes in operating assets and liabilities:
Contribution receivable		1,382			—
Prepaid expenses and other current assets		291			(319	)		(1,858	)		(1,355	)
Other long-term assets		(4	)		26			52			15
Accounts payable		1,830			1,045			(642	)		459
Accrued compensation		(1,223	)		(190	)		(793	)		(1,067	)
Accrued liabilities and other current liabilities		239			(66	)		(335	)		(632	)
Deferred rent, net of current portion		48			209
Other long-term liabilities								—			(23	)
Net cash used in operating activities		(11,883	)		(7,860	)		(29,513	)		(40,663	)
Investing activities
Purchase of marketable securities		(6,225	)		(59,214	)		(28,609	)		(86,567	)
Maturities of marketable securities		19,273			—			74,000			62,000
Purchase of property and equipment		(101	)		(294	)		(11	)		(59	)
Sale of property and equipment								1			272
Net cash provided by (used in) investing activities		12,947			(59,508	)		45,381			(24,354	)
Financing activities
Proceeds from issuance of convertible preferred stock, net of issuance costs		54,951			7,984
Proceeds from issuance of common stock upon exercise of stock options, net of repurchases		27			2
Payments of deferred offering costs		(569	)		—
Payments made on capital lease obligations		(17	)		—
Net cash provided by financing activities		54,392			7,986
Payment of debt principal								(20,000	)		—
Payment of debt issuance costs								(1,563	)		—
Proceeds from issuance of common stock under ATM offering program, net of issuance costs								744			12,003
Proceeds from sale of common stock and warrants under follow-on offering, net of issuance costs								—			41,650
Proceeds from issuance of common stock to Lincoln Park Capital Fund, net of issuance costs								—			910
Proceeds from issuance of common stock under 2018 ESPP								91			125
Net cash provided by (used in) financing activities								(20,728	)		54,688
Net increase (decrease) in cash, cash equivalents and restricted cash		55,456			(59,382	)		(4,860	)		(10,329	)
Cash, cash equivalents and restricted cash at beginning of year		7,848			89,736
Cash, cash equivalents and restricted cash at end of year	$	63,304		$	30,354
Supplemental Disclosures of Non-Cash Investing and Financing Information
Property and equipment included in accounts payable	$	34		$	126
Receipt of promissory note from related party for purchase of common stock	$	390		$	—
Receipt of promissory note from employees for purchase of common stock	$	400		$	—
Deferred offering costs included in accrued liabilities and accounts payable	$	1,138		$	—
Cash, cash equivalents and restricted cash at beginning of the period								13,632			34,351
Cash, cash equivalents and restricted cash at end of the period							$	8,772		$	24,022
Supplemental Disclosures of Cash Flow Information:
Cash paid for interest							$	1,969		$	1,577
Supplemental Disclosures of Non-Cash Investing and Financing Activities
Issuance of common stock in payment of debt							$	—		$	3,179

Cash and cash equivalents							$	7,876		$	22,576
Restricted cash								896			1,446
Total cash, cash equivalents and restricted cash							$	8,772		$	24,022

2. Summary of Significant Accounting Policies

Basis of Presentation

These condensed financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and the rules and regulations of the United States Securities and Exchange Commission (“SEC”) for interim reporting.

Certain information and footnote disclosures normally included in annual financial statements prepared in accordance with GAAP have been condensed or omitted. Accordingly, the unaudited condensed financial statements should be read in conjunction with the audited financial statements and the related notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2022 filed with the SEC.

The Company effected a reverse stock split on October 19, 2022 of its outstanding shares of common stock at a ratio of 1-for-10 pursuant to a Certificate of Amendment to the Company's Certificate of Incorporation filed with the Secretary of State of the State of Delaware. The reverse stock split was reflected on the Nasdaq Global Select Market beginning with the opening of trading on October 20, 2022. The reverse stock split did not change the par value of the Company's common stock or the authorized number of shares of the Company's common stock. All share amounts and per share amounts disclosed in this Quarterly Report on Form 10-Q have been restated to reflect the reverse stock split on a retroactive basis in all periods presented.

Unaudited Condensed Financial Statements

The accompanying financial information for the three and nine months ended September 30, 2023 and 2022 are unaudited. The unaudited condensed financial statements have been prepared on the same basis as the annual audited financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary to present fairly the Company’s financial position as of September 30, 2023 and its results of operations for the three and nine months ended September 30, 2023 and 2022 and cash flows for the nine months ended September 30, 2023 and 2022. The results for interim periods are not necessarily indicative of the results expected for the full fiscal year or any other periods.

Use of Estimates

The condensed financial statements have been prepared in accordance with GAAP, which requires management to make estimates and assumptions that affect the amounts and disclosures reported in the condensed financial statements and accompanying notes. The Company bases its estimates on historical experience and market-specific or other relevant assumptions that it believes are reasonable under the circumstances. The amounts of assets and liabilities reported in the Company’s condensed balance sheets and the amount of expenses and income reported for each of the periods presented are affected by estimates and assumptions, which are used for, but are not limited to, determining the fair value of assets and liabilities, ~~common stock valuation,~~the fair value of right-of-use assets and lease liabilities, and stock-based compensation. Actual results could differ from such estimates or assumptions.

Impairment of Long-Lived Assets

~~Deferred Offering Costs~~

~~Deferred offering costs, consisting~~The Company evaluates long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying value of ~~direct incremental legal, accounting, filing~~an asset may not be fully recoverable. If indicators of impairment exist and ~~other fees incurred related~~the undiscounted future cash flows that the assets are expected to generate are less than the ~~preparation~~carrying value of the ~~IPO, have been capitalized and were offset against proceeds upon completion~~assets, the Company reduces the carrying amount of the ~~offering in May 2018. As of March 31, 2018, $1.7 million of deferred offering costs were capitalized~~assets through an impairment charge, to their estimated fair value based on a discounted cash flow approach or, when available and ~~included in current assets on the balance sheet. There were no capitalized deferred offering costs at December 31, 2017.~~appropriate, to comparable market values.

Segments

~~Cash, Cash Equivalents and Restricted Cash~~

The Company considers all highly liquid investments with original maturities of 90 days or less from the date of purchase to be cash equivalents. Cash equivalents primarily include money market funds that invest in U.S. Treasury obligations which are stated at fair value.

The Company has ~~issued a letter of credit under a lease agreement which has been collateralized. This cash is classified as noncurrent restricted cash on the balance sheet based on the term of the underlying lease.~~

one operating segment. The ~~following table provides a reconciliation of cash, cash equivalents, and restricted cash within the balance sheets that sum to the total of the same amounts shown in the statements of cash flows.~~

March 31,

December 31,

2018

2017

(in thousands)

Cash and cash equivalents

$
62,754

$
7,298

Restricted cash

550

550

Total cash, cash equivalents, and restricted cash

$
63,304

$
7,848

~~Variable Interest Entities~~

The Company reviews agreements it enters into with third-party entities, pursuant to which the Company may have a variable interest in the entity, in order to determine if the entity is a variable interest entity (“VIE”). If the entity is a VIE, the Company assesses whether or not it is the primary beneficiary of that entity. In determining whether the Company is the primary beneficiary of an entity, the Company applies a qualitative approach that determines whether it has both (i) the power to direct the economically significant activities of the entity and (ii) the obligation to absorb losses of, or the right to receive benefits from, the entity that could potentially be significant to that entity. If the Company determines it is the primary beneficiary of a VIE, it consolidates that VIE intoCompany’s chief operating decision maker, its Chief Executive Officer, manages the Company’s ~~financial statements. The Company’s determination about whether it should consolidate such VIEs is made continuously as changes to existing relationships or future transactions may result in~~operations on a ~~consolidation or deconsolidation event.~~

~~Concentrations~~consolidated basis for the purposes of ~~Risk~~allocating resources.

Financial instruments that potentially subject the Company to significant concentrations of credit risk consist primarily of cash, cash equivalents, restricted cash, marketable securities and contribution receivable. Substantially all of the Company’s cash and cash equivalents and restricted cash is deposited in accounts with financial institutions that management believes are of high credit quality. Such deposits have and will continue to exceed federally insured limits. The Company maintains its cash with accredited financial institutions and accordingly, such funds are subject to minimal credit risk. The Company has not experienced any losses on its cash deposits. The contribution receivable is unsecured and is concentrated with one third-party organization, and accordingly the Company may be exposed to credit risk. To date, the Company has not experienced any loss related to its contributions receivable.

The Company’s investment policy limits investments to certain types of securities issued by the U.S. government, its agencies and institutions with investment-grade credit ratings and places restrictions on maturities and concentration by type and issuer. The Company is exposed to credit risk in the event of a default by the financial institutions holding its cash, cash equivalents, restricted cash and marketable securities and issuers of marketable securities to the extent recorded on the balance sheets. As of March 31, 2018, the Company had no off-balance sheet concentrations of credit risk.

The Company depends on third-party suppliers for key raw materials used in its manufacturing processes and is subject to certain risks related to the loss of these third-party suppliers or their inability to supply the Company with adequate raw materials.

Recently ~~Issued~~Adopted Accounting Pronouncements

In ~~January 2017,~~June 2016, the FASB issued ASU No. ~~2017-01,~~ ~~Business Combinations~~2016-13, Financial Instruments—Credit Losses (Topic ~~805): Clarifying~~326), Measurement of Credit Losses on Financial Instruments, as clarified in subsequent amendments. ASU 2016-13 changes the ~~Definition~~impairment model for certain financial instruments. The new model is a forward-looking expected loss model and will apply to financial assets subject to credit losses and measured at amortized cost and certain off-balance sheet credit exposures. This includes loans, held-to-maturity debt securities, loan commitments, financial guarantees and net investments in leases, as well as trade receivables. For available-for-sale debt securities with unrealized losses, credit losses will be measured in a manner similar to today, except that the losses will be recognized as allowances rather than reductions in the amortized cost of ~~a Business. This ASU clarifies~~ the ~~definition~~securities. In October 2019, the FASB voted to delay the effective date of ~~a business when evaluating whether transactions should~~this standard. Topic 326 will be ~~accounted for as acquisitions (or disposals) of assets or businesses. The guidance is~~ effective for ~~public business entities~~the Company for fiscal years beginning after December 15, 2017, and interim periods within those years. For all other entities, it is effective for fiscal years beginning after December 15, 2018, and interim periods within fiscal years beginning after December 15, 2019.2022. Early adoption is permitted. ~~The Company is currently evaluating the effect that this guidance will have~~We adopted ASU 2016-13 on ~~its financial statements.~~

~~In February 2016, the FASB issued ASU No. 2016-02 (“ASU 2016-02”),~~ ~~Leases(Topic 842), which supersedes the guidance in former ASC 840,~~ ~~Leases~~. The new standard requires lessees to apply a dual approach, classifying leases as either finance or operating leases based on the principle of whether or not the lease is effectively a financed purchase by the lessee. This classification will determine whether lease expense is recognized based on an effective interest method or on a straight-line basis over the term of the lease. A lessee is also required to record a right-of-use asset and a lease liability for all leases with a term of greater than 12 months regardless of their classification. Leases with a term of 12 months or less will be accounted for similar to existing guidance for operating leases today. For public entities, this standard is effective for annual reporting periods beginning after December 15, 2018, including interim periods within that reporting period. For all other entities, this standard is effective for annual reporting periods beginning after December 15, 2019, and interim periods within annual periods beginning after December 15, 2020. Early adoption is permitted. The ASU is expected to impact the Company’s financial statements as the Company has certain operating lease arrangements for which the Company is the lessee. Management expects that the adoption of this standard will result in the recognition of an asset for the right to use the leased facility on the Company’s balance sheet, as well as the recognition of a liability for the lease payments remaining on the lease. While the Company is currently evaluating the impact of the adoption of this standard on its financial statements, the Company anticipates the recognition of additional assets and corresponding liabilities on its balance sheet related to leases.

~~In May 2017, the Financial Accounting Standards Board (FASB) issued ASU No. 2017-09,~~ ~~Compensation-Stock Compensation (Topic 718)- Scope of Modification Accounting~~ (ASU 2017- 09). The amendments included in this update provide guidance about which changes to the terms or conditions of a share-based payment award require an entity to apply modification accounting. The amendments in this update will be applied prospectively to an award modified on or after the adoption date. The amendments in ASU 2017-09 became effective for the Company on January 1, ~~2018~~2023 and the adoption ~~of this standard~~ did ~~not~~not have a material impact on the Company’s condensed financial ~~statements.~~statements and related disclosures.

In ~~January 2016,~~November 2021, the FASB issued ASU ~~No. 2016-01,~~ ~~Financial Instruments Overall (Subtopic 825-10): Recognition and Measurement~~2021-10, Government Assistance, or Topic 832, which requires enhanced disclosures of ~~Financial Assets and Financial Liabilities~~. This guidance makes amendments to the classification and measurement of financial instruments and revises the accounting related to: (1) the classification and measurement of investments in equity securities (except for investmentstransactions with governments that are accounted for ~~under~~by applying a grant or contribution model. The

new pronouncement requires entities to provide information about the ~~equity method~~nature of ~~accounting);~~the transaction, terms and ~~(2) the presentation of certain fair value changes for financial liabilities measured at fair value. In addition, the update also amends certain disclosure requirements~~conditions associated with the ~~fair value of~~transaction and financial instruments. The guidance is effective for public business entities in 2018. For all other calendar-year entities, it is effective for annual periods beginning in 2019 and interim periods beginning in 2020. Early adoptions of certain amendments withinstatement line items affected by the ~~update are permitted.~~transaction. The Company ~~is currently evaluating~~adopted the ~~impact that the adoption of this guidance will have on its financial statements and related disclosures, including on the Company’s cost method investment.~~

~~In August 2016, the FASB issued ASU No. 2016-15,~~ ~~Statement of Cash Flows (Topic 230: Classification of Certain Cash Receipts and Cash Payments). This guidance addresses specific cash flow issues with the objective of reducing the diversity in practice~~standard for the treatment of these issues. The areas identified include: debt prepayment or debt extinguishment costs; settlement of zero-coupon debt instruments; contingent consideration payments made after a business combination; proceeds from the settlement of insurance claims; proceeds from the settlement of corporate-owned life insurance policies; distributions received from equity method investees; beneficial interests in securitization transactions; and application of the predominance principle with respect to separately identifiable cash flows. The guidance will generally be applied retrospectively and is effective for public business entities for fiscal yearsannual period beginning after December 15, 2017, and interim periods within those years. For all other entities, it is effective for fiscal years beginning after December 15, 2018, and interim periods within fiscal years beginning after December 15, 2019. Early adoption is permitted. The Company is currently evaluating the effect that this guidance will have on its financial statements and related disclosures.

~~On December 22, 2017, the U.S. federal government enacted the Tax Cuts and Jobs Act (“the Act”)~~January 1, 2023. The ~~Tax~~employee retention credit received under the CARES Act ~~contains, among other things, significant changes to corporate taxation, including reduction of the corporate tax rate from~~qualifies as a ~~top marginal rate of 35% to a flat rate of 21% for tax years beginning after December 31, 2017, limitation of the deduction for net operating losses to 80% of current year taxable income~~government assistance program under Topic 832 and ~~elimination of net operating loss carrybacks, implementing a territorial tax system, and requiring a mandatory one-time tax on U.S. owned undistributed foreign earnings and profits known~~resulted in enhanced required disclosures, as ~~the transition tax. In December 2017, SEC staff issued Staff Accounting Bulletin No. 118,~~ ~~Income Tax Accounting Implications of the Tax Cuts and Jobs Act~~ (“SAB 118”) to address the accounting implications of recently enacted U.S. federal tax reform. SAB 118 allows companies to record provisional amounts during a measurement period not to extend beyond one year of the enactment date to address ongoing guidance and tax interpretations that are expected over the next 12 months. The Company has adopted SAB 118 and currently considers its accounting of the impact of U.S. federal tax reform to be incomplete but continues to make a reasonable estimate of the effects on our existing deferred tax assets. The Company expects to complete the remainder of the analysis within the measurement perioddescribed in accordance with SAB 118. Adjustments, if any, are not expected to impact the statement of operations and comprehensive loss due to the full valuation allowance on the Company’s deferred tax assets.Note 7, "Government Assistance Program".

3. Fair Value Measurements

The Company determines the fair value of financial and non-financial assets and liabilities based on the assumptions that market participants would use in pricing the asset or liability in an orderly transaction between market participants at the measurement date. The identification of market participant assumptions provides a basis for determining what inputs are to be used for pricing each asset or liability. A fair value hierarchy has been established which gives precedence to fair value measurements calculated using observable inputs over those using unobservable inputs. This hierarchy prioritized the inputs into three broad levels as follows:

•

Level 1: Quoted prices in active markets for identical instruments

•

Level 2: Other significant observable inputs (including quoted prices in active markets for similar instruments)

•

Level 3: Significant unobservable inputs (including assumptions in determining the fair value of certain investments)

The carrying amounts of financial instruments such as cash and cash equivalents, restricted cash, ~~contributions receivable,~~ prepaid expenses and other current assets, accounts payable, accrued compensation, accrued and other current liabilities approximate the related fair values due to the short maturities of these instruments.

~~The fair~~ As the long-term debt is subject to variable interest rates that are based on market rates which are regularly reset, considering Level 2 inputs, the Company believes the carrying value of the ~~Company’s cost method investment is measured when it is deemed to be other-than- temporarily impaired.~~long-term debt approximates its fair value.

The Company’s financial assets and liabilities subject to fair value measurements ~~on a recurring basis~~ and the level of inputs used in such measurements were as ~~follows:~~follows (in thousands):

March 31, 2018

Total

Level 1

Level 2

Level 3

(in thousands)

Money market funds

$
62,085

$
62,085

$
—

$
—

Total

$
62,085

$
62,085

$
—

$
—

Short-term marketable securities:

Commercial paper

5,428

—

5,428

—

Corporate debt securities

10,140

—

10,140

—

Asset-backed securities

14,404

—

14,404

—

U.S. government debt securities

41,309

—

41,309

—

Total short-term marketable securities

71,281

—

71,281

—

Total

$
133,366

$
62,085

$
71,281

$
—


	September 30, 2023
	Total		Level 1		Level 2		Level 3
Assets:
Cash equivalents:
Money market funds	$	4,912	$	4,912	$	—	$	—
Total cash equivalents		4,912		4,912		—		—
Short-term marketable securities:
U.S. treasuries		7,736		—		7,736		—
U.S. government debt securities		30,327		—		30,327		—
Total short-term marketable securities		38,063		—		38,063		—
Total assets subject to fair value measurements	$	42,975	$	4,912	$	38,063	$	—


	December 31, 2022
	Total		Level 1		Level 2		Level 3
Assets:
Cash equivalents:
Money market funds	$	5,083	$	5,083	$	—	$	—
Total cash equivalents		5,083		5,083		—		—
Short-term marketable securities:
U.S. treasuries		30,758		—		30,758		—
U.S. government debt securities		51,301		—		51,301		—
Total short-term marketable securities		82,059		—		82,059		—
Total assets subject to fair value measurements	$	87,142	$	5,083	$	82,059	$	—

December 31, 2017

Total

Level 1

Level 2

Level 3

(in thousands)

Money market funds

$
5,709

$
5,709

$
—

$
—

Total

$
5,709

$
5,709

$
—

$
—

Short-term marketable securities:

Commercial paper

6,359

—

6,359

—

Corporate debt securities

16,149

—

16,149

—

Asset-backed securities

14,588

—

14,588

—

U.S. government debt securities

42,116

—

42,116

—

Long-term marketable securities:

Asset-backed securities

2,742

—

2,742

—

U.S. government debt securities

2,376

—

2,376

—

Total marketable securities

84,330

—

84,330

—

Total

$
90,039

$
5,709

$
84,330

$
—

The ~~Company estimates~~Company's available-for-sale investments rely on the fair value of its money market funds, commercial paper, corporate debt securities, asset-backed securities, and U.S. government debt securities by taking into consideration valuations obtained from third-party pricing services. The pricing services that utilize industry standard valuation models, including both income and market-based approaches, for which all significant inputs are observable, either directly or indirectly, to estimate fair value. These inputs include reported trades of and broker/dealer quotes on the same or similar securities, issuer credit spreads; benchmark securities; prepayment/default projections based on historical data; and other observable inputs.

~~There were no transfers within~~ See Note 4, “Marketable Securities,” for further information regarding the ~~hierarchy during the three months ended March 31, 2018 and the year ended December 31, 2017.~~

~~The grant date fair~~carrying value of the Company’s common stock has been determined by the Company’s Board of Directors with the assistance of management and an independent third-party valuation specialist. The grant date fair value of the Company’s common stock was determined using valuation methodologies which utilizes certain assumptions including probability weighting of events, volatility, time to liquidation, a risk-free interest rate and an assumption for a discount for lack of marketability (Level 3 inputs). In determining the fair value of the Company’s common stock, the methodologies used to estimate the enterprise value of the Company were performed using methodologies, approaches, and assumptions consistent with the American Institute of Certified Public Accountants Accounting and Valuation Guide, ~~Valuation of Privately-Held-Company Equity Securities Issued as Compensation~~ ~~(“AICPA Accounting and Valuation Guide”).~~Company's financial instruments.

Marketable securities, which are classified as available-for-sale, consisted of the following as of ~~March 31, 2018:~~September 30, 2023, (in thousands):

Amortized
Cost Basis

Unrealized
Gains

Unrealized
Losses

Fair
Value

(in thousands)

Short-term marketable securities:

Commercial paper

$
5,445

$
—

$
(17
)

$
5,428

Corporate debt securities

10,167

—

(27
)

10,140

Asset-backed securities

14,446

—

(42
)

14,404

U.S. government debt securities

41,361

—

(52
)

41,309

Total short term marketable securities

$
71,419

$
—

$
(138
)

$
71,281


	Amortized Cost Basis		Unrealized Gains		Unrealized Losses			Fair Value
Cash equivalents:
Money market funds	$	4,912	$	—	$	—		$	4,912
Total cash equivalents		4,912		—		—			4,912
Short-term marketable securities:
U.S. treasuries		7,759		—		(23	)		7,736
U.S. government debt securities		30,359		1		(33	)		30,327
Total short-term marketable securities		38,118		1		(56	)		38,063
Total	$	43,030	$	1	$	(56	)	$	42,975

Marketable securities, which are classified as available-for-sale, consisted of the following as of December 31, ~~2017:~~2022 (in thousands):

Amortized
Cost Basis

Unrealized
Gains

Unrealized
Losses

Fair
Value

(in thousands)

Short-term marketable securities:

Commercial paper

$
6,369

$
—

$
(10
)

$
6,359

Corporate debt securities

16,162

—

(13
)

16,149

Asset-backed securities

14,604

—

(16
)

14,588

U.S. government debt securities

42,172

—

(56
)

42,116

Total short-term marketable securities

79,307

—

(95
)

79,212

Long-term marketable securities:

Asset-backed securities

2,752

—

(10
)

2,742

U.S. government debt securities

2,375

1

—

2,376

Total long-term marketable securities

5,127

1

(10
)

5,118

Total marketable securities

$
84,434

$
1

$
(105
)

$
84,330


	Amortized Cost Basis		Unrealized Gains		Unrealized Losses			Fair Value
Cash equivalents:
Money market funds	$	5,083	$	—	$	—		$	5,083
Total cash equivalents		5,083		—		—			5,083
Short-term marketable securities:
U.S. treasuries		30,820		1		(63	)		30,758
U.S. government debt securities		51,491		6		(196	)		51,301
Total short-term marketable securities		82,311		7		(259	)		82,059
Total	$	87,394	$	7	$	(259	)	$	87,142

At ~~March 31, 2018,~~ September 30, 2023, the remaining contractual maturities of available-for-sale securities were less than ~~two years~~one year. There have been no significant realized gains or losses on available-for-sale securities for the periods presented. ~~Available-for-sale debt~~As of September 30, 2023, the Company did not hold any individual securities in an unrealized loss position for 12 months or greater. The Company has the ability and intent to hold all marketable securities that ~~were~~have been in a continuous loss position ~~but were~~until maturity or recovery. No significant facts or circumstances have arisen to indicate that there has been any significant deterioration in the creditworthiness of the issuers of the securities held by the Company. The Company considered the current and expected future economic and market conditions and determined that the estimate of credit losses was not ~~deemed~~significantly impacted. Thus, there has been no change in estimate of expected credit loss during the three and nine months ended September 30, 2023 and no allowance for credit loss was recorded at September 30, 2023. The Company will continue to beassess the current and expected future economic and market conditions as further development arises.

See Note 3, “Fair Value Measurements,” for further information regarding the fair value of the Company’s financial instruments.

8. Commitments and Contingencies

~~Indemnifications~~Leases

In February 2019, the Company entered into a lease agreement for new office and laboratory space in South San Francisco, California. The term of the lease agreement commenced in May 2019. The lease has an initial term from occupancy of approximately ten years ending on December 31, 2029 with an option to extend the term for an additional eight years at then-market rental rates. The total base rent payment escalates annually based on a fixed percentage beginning from the 13th month of the lease agreement. The Company will also be responsible for the operating expenses and real estate taxes allocated to the building and common areas. Pursuant to the lease agreement, the landlord provided the Company with a tenant improvement allowance of $10.7 million, which was included in deferred rent and leasehold improvements on the balance sheet at December 31, 2019. In connection with the execution of the lease agreement, the Company delivered a letter of credit of approximately $0.9 million to the landlord.

The Company’s operating leases include various covenants, indemnities, defaults, termination rights, security deposits and other provisions customary for lease transactions of this nature.

The following table summarizes the components of lease expense, which are included in operating expenses in the Company’s condensed statements of operations and comprehensive loss (in thousands):


	Three Months Ended September 30,						Nine Months Ended September 30,
	2023			2022			2023			2022
Operating lease cost	$	930		$	1,088		$	2,790		$	3,239
Variable lease cost		203			407			546			1,114
Sublease income		(976	)		(1,391	)		(2,904	)		(3,405	)
Total lease cost	$	157		$	104		$	432		$	948

Variable lease payments include amounts relating to common area maintenance, real estate taxes and insurance and are recognized in the condensed statements of operations and comprehensive loss as incurred.

The following table summarizes supplemental information related to leases (in thousands):


	Nine Months Ended September 30,
	2023			2022
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows from operating leases	$	3,599		$	5,109
Weighted-average remaining lease term (years)
Operating leases		6.3			7.3
Weighted-average discount rate (percentage)
Operating leases		6.0	%		6.0	%

The following table summarizes the maturities of lease liabilities as of September 30, 2023 (in thousands):


	Amount
2023 (remaining 3 months)	$	1,211
2024		4,964
2025		5,123
2026		5,287
2027		5,457
Thereafter		11,435
Total future minimum lease payments		33,477
Less: Amount representing interest		(5,684	)
Present value of future minimum lease payments		27,793
Less: Current portion of operating lease liability		(3,362	)
Noncurrent portion of operating lease liability	$	24,431

In June 2021, the Company entered into an agreement to sublease a portion of the first floor of the South San Francisco, California facility, consisting of approximately 23,000 square feet, to Freenome Holdings, Inc., through June 30, 2024. The base sublease rent rate is $6.25 per rental square foot per month and will increase annually by 3.5% through expiration of the agreement. Additionally, the subtenant is required to pay approximately 37% of operating expenses and property management fees that the Company is required to pay under the lease for the South San Francisco, California facility. The Company incurred initial direct costs of $0.2 million in sublease commissions related to entering into the agreements to sublease the South San Francisco, California facility. To account for the commissions, the Company capitalized the total commissions amount and will amortize the balance over the term of the sublease. Sublease income was $0.6 million and $1.0 million for the three months ended September 30, 2023 and 2022, respectively, and $1.7 million and $2.1 million for the nine months ended September 30, 2023 and 2022, respectively, which was offset against total rent expense.

In May 2022, the Company entered into an agreement to sublease a portion of the second floor of the South San Francisco, California facility, consisting of approximately 15,000 square feet, to Initial Therapeutics, Inc. ("Initial Therapeutics"). The original sublease term commenced on July 1, 2022 and continued through June 30, 2024 and further extended through June 30, 2026 upon execution of an amendment as defined below. The base sublease rent rate is $7.80 per rental square foot per month and will increase by 3.5% annually through the expiration of the agreement. Additionally, the subtenant is required to pay approximately 24% of operating expenses and property management fees that the Company is required to pay under the lease for the South San Francisco, California facility. The Company incurred initial direct costs of $0.1 million in sublease commissions related to entering into the agreements to sublease the South San Francisco, California facility. To account for the commissions, the Company capitalized the total commissions amount and will amortize the balance over the term of the sublease. Sublease income was $0.4 million and $0.4 million for the three months ended September 30, 2023 and 2022, respectively, and $1.2 million and $0.4 million for the nine months ended September 30, 2023 and 2022, respectively, which was offset against total rent expense.

On September 15, 2023, the Company entered into an amendment with Initial Therapeutics to sublease the remainder of the second floor of the South San Francisco, California facility, consisting of an additional 17,000 square feet. The sublease term will commence on October 1, 2023 and extends the existing sublease agreement that commenced on July 1, 2022 through June 30, 2026. The additional space will be subleased at a monthly rent rate of $1.00 per square foot starting a month after Initial Therapeutics first takes possession of the additional space through June 30, 2024. Starting July 1, 2024, the rent rate for the entirety of Initial Therapeutics' subleased space will be $6.02 per rental square foot per month and will increase 3.5% on December 1, 2024 and 2025. Additionally, Initial Therapeutics will be required to pay approximately 51% of operating expenses and property management fees that the Company is required to pay under the lease for the South San Francisco, California facility. The Company incurred initial direct costs of $0.3 million in sublease commissions.

On September 15, 2023, the Company entered into a sub-sublease agreement with GT Biopharma, Inc. to sublease a portion of its first floor at 8000 Marina Boulevard, Brisbane, California, consisting of 4,500 square feet. The sub-sublease term will commence on October 6, 2023 through June 30, 2024. The space will be subleased at a rent rate of $2.00 per rent square feet.

Impairment of Operating Lease Right-of-Use Asset and Other Long-Lived Assets

The Company is subleasing its South San Francisco facility through June 30, 2026, the Company determined an impairment indicator was present. The Company determined all of its long-lived assets represent entity wide asset group for the purpose of the long-lived asset impairment assessment. The Company concluded that the carrying value of the entity wide asset group was not recoverable as it exceeded the future net undiscounted cash flows that are expected to be generated from the use and eventual disposition of the assets within the asset group. To allocate and recognize the impairment loss, the Company determined the fair value of the Company using the adjusted net asset method under the cost approach. The implied allocated impairment loss to any individual asset within the long-lived asset group shall not reduce the carrying amount of that asset below its fair value. To determine the fair value of the individual assets within the asset group, the Company utilized the discounted cash flow method using the income approach. Based on this analysis, during the three and nine months ended September 30, 2023, the Company recognized a non-cash impairment charge of $5.6 million, including $4.0 million for the right-of-use assets and $1.6 million for the leasehold improvements. This represents a Level 3 nonrecurring fair value measurement. Calculating the fair value of the assets involves significant estimates and assumptions. These estimates and assumptions include, among others, projected future cash flows, risk-adjusted discount rates and market conditions. Changes in the factors and assumptions used could materially affect the amount of impairment loss recognized in the period the asset was considered impaired.

Indemnifications

The Company indemnifies each of its officers and directors for certain events or occurrences, subject to certain limits, while the officer or director is or was serving at the Company’s request in such capacity, as permitted under Delaware law and in accordance with the Company’s amended and restated certificate of incorporation and bylaws.

The term of the indemnification period lasts as long as an officer or director may be subject to any proceeding arising out of acts or omissions of such officer or director in such capacity.

The maximum amount of potential future indemnification is unlimited; however, the Company currently holds director and officer liability insurance. This insurance allows the transfer of risk associated with the Company’s exposure and may enable the Company to recover a portion of any future amounts paid. The Company believes that the fair value of these potential indemnification obligations is minimal. Accordingly, the Company has not recognized any liabilities relating to these obligations for any period presented.

10. Equity Financing

On October 19, 2022, the Company effected a reverse stock split of its outstanding share of common stock at a ratio of 1-for-10 pursuant to a Certificate of Amendment to the Company's Certificate of Incorporation filed with the Secretary of State of the State of Delaware. The reverse stock split was reflected on the Nasdaq Global Select Market beginning with the opening of trading on October 20, 2022. All share amounts and per share amounts disclosed in this Quarterly Report on Form 10-Q have been restated to reflect the reverse stock split on a retroactive basis in all periods presented.

The Company has 10,000,000 shares of convertible preferred stock authorized for issuance, par value of $0.0001 per share. As of September 30, 2023 and December 31, 2022, no shares of preferred stock were issued and outstanding.

The Company has 300,000,000 shares of common stock authorized for issuance, par value of $0.0001 per share. Holders of the Company’s common stock are entitled to one vote per share. As of September 30, 2023 and December 31, 2022, there were 14,614,890 and 14,215,302 shares, respectively, of common stock issued and outstanding.

Follow-On Offering

In August 2022, the Company closed an underwritten offering (the “Follow-On Offering”) in ~~aggregate. All of these related party full-recourse notes were repaid on April 4, 2018 in accordance with the terms of such notes.~~

~~In October 2017,~~which the Company issued ~~two promissory notes to an executive officer for $1.6 million~~ and $0.5 million, each with an interest rate of 1.85% per annum. The aggregate principal amount of $2.1 million was used to purchase 625,084 shares of restricted stock. The promissory notes were considered to be non-recourse in substance and accordingly, the shares sold subject to such promissory notes are considered an option for accounting purposes. In April 2018, the Company’s board of directors approved the forgiveness of all outstanding principal and accrued interest of the $1.6 million non-recourse promissory note. The non-recourse promissory note outstanding of $0.5 million was repaid on April 4, 2018 in accordance with the terms of the note.

~~In January 2018, the Company~~ ~~issued full-recourse promissory notes to an executive and an executive officer of the Company for~~ an aggregate ~~principal amount~~ of ~~$0.4 million with an interest rate of 2.5% per annum. All of the principal was used to early exercise options for 114,406 shares~~6,428,571 of the Company’s common ~~stock. The full recourse note of $0.2 million for the executive officer was repaid on April 4, 2018 in accordance~~stock together with ~~the terms of the note.~~

~~Financing Activities~~

~~During the three months ended March 31, 2018, the Company issued convertible preferred stock for total proceeds of $3.0 million~~warrants (the "Existing Warrants”) to ~~shareholders who are considered~~purchase up to ~~be related parties.~~

~~8. Convertible Preferred Stock and Common Stock~~

~~Convertible Preferred Stock~~

In March 2018, the Company amended and restated its certificate of incorporation to, among other things, (i) increase its authorized shares of common stock from 122,000,000 to 140,000,000 shares, (ii) increase its authorized shares of preferred stock from 91,739,149 to 103,283,818 shares, of which 11,544,669 shares are designated as Series C convertible preferred stock, and (iii) set forth the rights, preferences and privileges of the Series C convertible preferred stock. ~~In March 2018, the Company sold 3,590,573 shares of Series C convertible preferred stock at $15.3317 per share for net proceeds of $54.9 million and in~~ ~~April 2018, the Company sold an additional 322,852 shares of Series C convertible preferred stock $15.3317 per share for net proceeds of $5.0 million.~~ .

Each share of Series C convertible preferred stock was convertible into one share of the Company’s common stock. Each share of preferred stock was automatically convert into one share of common stock upon the consummation of a qualified public offering. A qualified public offering was defined as an initial public offering that resulted in listing

~~on a U.S. national securities exchange and at least $30.0 million of gross proceeds at a per share price of not less than the Series C original issue price of $15.3317.~~

The Company evaluated the other rights, preferences and privileges of each series of convertible preferred stock and concluded that there were either no freestanding derivative instruments or any embedded derivatives requiring bifurcation.

~~Convertible preferred stock consisted of the following:~~

At March 31, 2018

Shares
Authorized

Shares Issued
and
Outstanding

Liquidation
Preference

Carrying
Value

(in thousands, except for share amounts)

Series A-1

9,085,738

2,887,086

$
2,495

$
2,457

Series A-2

32,653,411

10,498,269

9,198

9,214

Series B

50,000,000

14,774,369

179,132

162,285

Series C

11,544,669

3,590,573

55,000

54,951

Total convertible preferred stock

103,283,818

31,750,297

$
245,825

$
228,907

At December 31, 2017

Shares
Authorized

Shares Issued
and
Outstanding

Liquidation
Preference

Carrying
Value

(in thousands, except for share amounts)

Series A-1

9,085,738

2,887,086

$
2,495

$
2,457

Series A-2

32,653,411

10,498,269

9,198

9,214

Series B

50,000,000

14,774,369

179,132

162,285

Total convertible preferred stock

91,739,149

28,159,724

$
190,825

$
173,956

~~Conversion Rights~~

Each share of convertible preferred stock was convertible at the right and option of the stockholder, at any time after the date of issuance, into such number of fully paid and non-assessable shares of common stock on a one for one ratio (1:1 conversion ratio). The Series A-1 conversion price was $0.864 per share, the Series A-2 conversion price was $0.876 per share, the Series B conversion price was $12.125 per share and the Series C conversion price was $15.3317, in each case, subject to certain antidilution adjustments as provided in the Company’s amended and restated certificate of incorporation.

Each share of convertible preferred stock was automatically convertible into a fully paid, non-assessable share of common stock at the then-effective conversion rate for such share (i) upon the closing of a firm commitment, underwritten initial public offering6,428,572 of the Company’s common stock at an offering price of at an aggregate offering price of $7.00 per unit. The Existing Warrants have an exercise price of $8.50 per share underlying the Existing Warrant. These Existing Warrants were recorded as a component of stockholders’ equity within additional paid-in capital. The gross proceeds ~~of not less than $30.0 million and a price per share~~ to the ~~public of not less than $15.3317 per share; or (ii) upon the receipt by the~~ Company ~~of a written request for such conversion from at least 60%~~were $45.0 million before deducting underwriting discounts and commissions and other offering expenses. The net proceeds of the ~~holders~~Follow-On Offering were approximately $41.7 million.

The Existing Warrants are exercisable at any time after their original issuance and on or prior to the five-year anniversary of the ~~convertible preferred stock then outstanding (voting~~original issuance date. A holder of Existing Warrants may not exercise the warrant if the holder, together ~~as a single class and on an as-converted basis), or if later, the effective date for conversion specified in such requests.~~

~~Liquidation Rights~~

~~In the event~~with its affiliates, would beneficially own more than 4.99% of any voluntary or involuntary liquidation, dissolution or winding up of the Company or a deemed liquidation event, as further defined in the Company’s amended and restated certificate of incorporation, prior to and in preference to any distribution of any of the assets of the Company to the holders of Series B convertible preferred stock and the Series A-1 and Series A-2 convertible preferred stock and common stock, the holders of Series C convertible preferred stock would have been paid, on a ~~pari passu~~ ~~basis, an amount per share equal to the Series C liquidation preference of $15.3317 per share, plus an amount equal to any dividends declared but unpaid thereon~~

(the “Series C Liquidation Preference”). If upon any such liquidation, dissolution or winding up of the Company or a deemed liquidation event, the assets of the Company available for distribution to its stockholders had been insufficient to pay the holders of Series C convertible preferred stock the full amount to which they were entitled, the holders of the Series C convertible preferred stock would have shared ratably in any distribution of the assets available for distribution in proportion to the respective amounts which would otherwise have been payable in respect of the shares held by them upon such distribution if all amounts payable on or with respect to such shares were paid in full.

After the payment or setting aside for payment to the holders of the Series C convertible preferred stock of the full amount of the Series C Liquidation Preference, prior to any distribution of any of the assets of the Company to the holders of the Series A-1 and Series A-2 convertible preferred stock and common stock, the holders of Series B convertible preferred stock would have been paid, on a ~~pari passu~~ basis, an amount per share equal to the Series B liquidation preference of $12.125 per share for Series B, plus, in each case, an amount equal to any dividends declared but unpaid thereon (the “Series B Liquidation Preference”). If upon any such liquidation, dissolution or winding up of the Company or deemed liquidation event, the assets of the Company available for distribution to its stockholders had been insufficient to pay the holders of shares of Series B convertible preferred stock the full amount to which they shall be entitled, the holders of the Series B convertible preferred stock would have shared ratably in any distribution of the assets available for distribution in proportion to the respective amounts which would otherwise have been payable in respect of the shares held by them upon such distribution if all amounts payable on or with respect to such shares were paid in full.

After the payment or setting aside for payment to the holders of the Series B convertible preferred stock of the full amount of the Series B Liquidation Preference, prior to any distribution of any of the assets of the Company to the holders of the common stock, the holders of Series A-1 and Series A-2 convertible preferred stock would have been paid, on a pari passu basis, an amount per share equal to $0.864 per share for Series A-1 and $0.876 per share for Series A-2, plus, in each case, an amount equal to any dividends declared but unpaid thereon (the “Series A Liquidation Preference”). If upon any such liquidation, dissolution or winding up of the Company or deemed liquidation event, the assets of the Company available for distribution to its stockholders had been insufficient to pay the holders of shares of Series A-1 and Series A-2 convertible preferred stock the full amount to which they shall be entitled, the holders of the Series A-1 and Series A-2 convertible preferred stock would have shared ratably in any distribution of the assets available for distribution in proportion to the respective amounts which would otherwise have been payable in respect of the shares held by them upon such distribution if all amounts payable on or with respect to such shares were paid in full.

After the payments or setting aside for payment to the holders of convertible preferred stock of the full amounts specified above, the entire remaining assets of the Company legally available for distribution shall be distributed pro rata to holders of the common stock of the Company in proportion to the number of shares of common stock ~~held by them.~~outstanding immediately after giving effect to such exercise. No warrants have been exercised as of September 30, 2023.

~~Voting Rights~~At-the-Market Offering

~~The holders~~In March 2022, the Company filed a Registration Statement on Form S-3 (the “March 2022 Shelf Registration Statement”), covering the offering of ~~outstanding shares~~up to $125.0 million of ~~Series A-1 and Series A-2 convertible~~common stock, preferred stock, ~~voting together~~debt securities, warrants, and units, which was declared effective by the SEC in May 2022. In March 2022, the Company also entered into a sales agreement (the “March 2022 Sales Agreement”) with Cowen and Company, LLC ("Cowen") as ~~a single class, were entitled~~sales agent to ~~elect two members~~sell shares of the Company’s ~~Board~~common stock, from time to time, with aggregate gross sales proceeds of ~~Directors. The holders~~up to $50.0 million pursuant to the March 2022 Shelf Registration Statement as an “at-the-market” offering under the Securities Act (the "March 2022 ATM Offering Program"). Cowen is entitled to up to 3.0% of ~~outstanding~~the gross proceeds of any shares of ~~Series B convertible preferred~~common stock ~~voting together~~sold under the March 2022 Sales Agreement. For so long as ~~a single class,~~its public float is less than $75.0 million, it may not sell more than the equivalent of one-third of its public float during any 12 consecutive months pursuant to the "baby shelf" rules. During the nine-month period ended September 30, 2023, there were ~~entitled~~274,781 shares of the Company's common stock sold pursuant to ~~elect one member~~the March 2022 Sales Agreement and the Company received total net proceeds of approximately $1.0 million, after deducting commissions and other offering expenses which was insignificant. On August 17, 2022, the Company entered into Amendment No. 1 (the “Amendment”) to the March 2022 Sales Agreement, which Amendment decreased the amount of the Company’s ~~Board~~common stock that can be sold by the Company through Cowen under the March 2022 Sales Agreement, from an aggregate offering of ~~Directors.~~

~~Additionally, each holder~~up to $50.0 million to an aggregate offering of up to $25.0 million. Following the ~~Company’s convertible preferred stock was entitled to a vote equal to the number~~Amendment, $14.6 million of shares of common stock remained available for sale under the March 2022 Sales Agreement, as amended, as of September 30, 2023. On March 17, 2023, the Company entered into ~~which~~Amendment No. 2 (the "Second Amendment"), accompanied by a

prospectus supplement, to the March 2022 Sales Agreement. The Second Amendment added the limitations imposed on the Program by General Instruction I.B.6 of Form S-3 (“Instruction I.B.6”) to the Sales Agreement. Pursuant to Instruction I.B.6, in no event will the Company sell ATM Shares through the Program with a value exceeding more than one-third of the Company’s “public float” (the market value of the Company’s outstanding common stock held by non-affiliates) in any twelve-month period so long as the Company’s public float remains below $75.0 million.

In October 2022, the Company filed a Registration Statement on Form S-3 (the “October 2022 Shelf Registration Statement”), covering the offering of up to $250.0 million of common stock, preferred stock, debt securities, warrants, and units. In October 2022, the Company also entered into a sales agreement (the “October 2022 Sales Agreement”) with Cowen as sales agent to sell shares of ~~convertible preferred~~the Company’s common stock, ~~could have been converted~~from time to time, with aggregate gross sales proceeds of up to $50.0 million pursuant to the October 2022 Shelf Registration Statement as an “at-the-market” offering under the Securities Act. Cowen is entitled to up to 3.0% of the ~~record date. The holders~~gross proceeds of ~~convertible preferred were entitled to vote on all matters on which the common stock shall be entitled to vote.~~

~~Dividend Rights~~

Holders of the Series A-1, Series A-2, Series B and Series C convertible preferred stock were entitled to receive non-cumulative dividends at a rate of 6% of the original respective series of convertible preferred stock issuance price. Only after payment of the dividends to the holders of Series C convertible preferred stock were the holders of shares of Series B, Series A-1 and Series A-2 convertible preferred stock be entitled to receive dividends, out of any ~~assets legally available therefore, prior and in preference to any declaration or payment of any dividend (other than dividends on the common stock payable solely in common stock) on the common stock.~~

After the payment or setting aside for payment of the dividends described above, any additional dividends (other than dividends on common stock payable solely in common stock) set aside or paid in any fiscal year could have been set aside or paid among the holders of the convertible preferred stock and common stock then outstanding on a pari passu basis in proportion to the greatest whole number of shares of common stock ~~which would have been held by each such holder if all~~sold under the October 2022 Sales Agreement. During the nine months ended September 30, 2023, there were no shares of ~~convertible preferred~~the Company's common stock ~~were converted~~sold pursuant to the October 2022 Sales Agreement.

Equity Purchase Agreement

In September 2021, the Company entered into an equity purchase agreement (the “Purchase Agreement” or “Equity Purchase Agreement”) and a registration rights agreement with Lincoln Park Capital Fund, LLC (“Lincoln Park” or “Investor”) which provides for the sale to Lincoln Park up to $30,000,000 of shares (the “Purchase Shares”) of its common stock over the thirty-six (36) month term of the Purchase Agreement. In connection with the Purchase Agreement, Lincoln Park purchased 102,040 Purchase Shares at a purchase price of $2.94 per share, for a total gross purchase price of $3.0 million (the “Initial Purchase”), and the ~~then-effective conversion rate.~~Company issued 25,244 shares of common stock to Lincoln Park as a commitment fee in connection with entering into the Purchase Agreement. The Company recognized $0.8 million of other expense relating to the commitment fee share issuance. From the date of the agreement through December 31, 2022, the Company had initiated the purchase of an additional 380,000 shares of the Company’s common stock amounting to $6.2 million in gross proceeds. The Company has initiated no purchases through the Purchase Agreement for the three- and nine-month period ended September 30, 2023.

~~Dividends were only payable as and if declared by~~Under the ~~Board of Directors. To date,~~Purchase Agreement, the Company has ~~not declared or paid~~sole discretion, subject to certain conditions, on any ~~dividends.~~

~~Redemption Rights~~

~~The convertible preferred stock was not mandatorily redeemable as it did not have a set redemption date or a date after which the shares may be redeemed~~business day selected by the holders. A redemption event would have occurred only upon the occurrence of certain change in control events that are outside the Company’s control, including a sale, lease, transfer, or other disposition of all or substantially all of the Company’s assets. The Company has elected not to adjust the carrying values of the convertible preferred stock to the liquidation preferences of such shares because it is uncertain whether or when an event would have occurred that would obligate the Company to ~~pay the liquidation preferences~~require Lincoln Park to ~~holders of~~purchase up to 10,000 shares of ~~convertible preferred stock. Subsequent adjustments~~common stock (the “Regular Purchase Amount”) at the Purchase Price (as defined below) per purchase notice (each such purchase, a “Regular Purchase”). The Regular Purchase Amount may be increased as follows: up to 15,000 shares if the closing price is not below $35.00, up to 20,000 shares if the closing price is not below $50.00, and up to 25,000 shares if the closing price is not below $70.00. Lincoln Park’s committed obligation under each Regular Purchase is capped at $2,000,000, unless the parties agree otherwise. The purchase price for Regular Purchases (the “Purchase Price”) shall be equal to the ~~carrying values~~lesser of: (i) the lowest sale price of the ~~liquidation preferences will be made only when it becomes probable that such a liquidation event will occur.~~ common shares during the Purchase Date, or (ii) the average of the three (3) lowest closing sale prices of the common shares during the ten (10) business days prior to the Purchase Date.

~~9. Stock-Based Compensation~~

~~2018 Incentive Award Plan~~

In ~~March 2018,~~addition to Regular Purchases and subject to certain conditions and limitations, the ~~Company’s board~~Company in its sole discretion may require Lincoln Park on each Purchase Date to purchase on the following business day up to the lesser of directors adopted the Company’s 2018 Incentive Award Plan (the “2018 Plan”). The 2018 Plan was approved by the Company’s stockholders in April 2018 and became effective on May 2, 2018. The 2018 Plan initially reserved 4,289,936 shares for the issuance of stock options as well as any automatic annual increases in(i) three (3) times the number of shares purchased pursuant to such Regular Purchase or (ii) 30% of the trading volume on the Accelerated Purchase Date (the “Accelerated Purchase”) (unless the Parties agree otherwise) at a purchase price equal to the lesser of 97% of (i) the closing sale price on the Accelerated Purchase Date, or (ii) the Accelerated Purchase Date’s volume weighted average price (the “Accelerated Purchase Price”). The Company has the sole right to set a minimum price threshold for each Accelerated Purchase in the notice provided with respect to such Accelerated Purchase and under certain circumstances and in accordance with the Purchase Agreement the Company may direct multiple Accelerated Purchases in a day.

The aggregate number of shares that the Company can sell to Lincoln Park under the Purchase Agreement may not exceed 1,106,580 shares of the common stock (which is equal to approximately 19.99% of the shares of the common stock outstanding immediately prior to the execution of the Purchase Agreement) (the “Exchange Cap”), unless (i) shareholder approval is obtained to issue Purchase Shares above the Exchange Cap, in which the Exchange Cap will no longer apply, or (ii) the average price of all applicable sales of common stock ~~reserved for future issuance~~to Lincoln Park under the ~~2018 Plan. Awards granted~~Purchase Agreement equals or exceeds $29.40 per share; provided that at no time may Lincoln Park (together with its affiliates) beneficially own more than 9.99% of the Company’s issued and outstanding common stock.

The Purchase Agreement contains customary representations, warranties, covenants, closing conditions, indemnification and termination provisions. The Purchase Agreement may be terminated by the Company at any time,

at its sole discretion, without any cost or penalty, by giving one business day notice to Lincoln Park. Further, Lincoln Park has covenanted not to engage in any direct or indirect short selling or hedging of the Common Shares. There are no limitations on the use of proceeds, financial or business covenants, restrictions on future financings (other than restrictions on the Company’s ability to enter into a similar type of agreement or Equity Line of Credit during the Term, excluding an At-The-Market transaction with a registered broker-dealer), rights of first refusal, participation rights, penalties or liquidated damages in the Purchase Agreement. Issuances under the ~~2018 Plan expire no later than ten years from~~Purchase Agreement were to be made pursuant to the ~~date~~Company's Registration Statement on Form S-3 filed in July 2019, which has since expired. The Company would need to file a new prospectus supplement covering issuances under the Purchase Agreement in order to continue using the facility.

~~During the three months ended March 31, 2018, the Board of Directors granted performance contingent stock option awards exercisable for 53,575 shares, to certain members~~A summary of the Company’s ~~executive team. These~~restricted stock units (“RSUs”), performance stock units (“PSUs”), and restricted stock awards ~~had a weighted average exercise price of $3.42 which was based on~~(“RSAs”) activity for the ~~fair market value on the grant date,~~nine months ended September 30, 2023 is as ~~determined by the Board of Directors, and vest upon the successful achievement of one or more specified performance goals.~~follows:

~~The total estimated fair value of employee performance contingent stock option awards was estimated at the date of grant using a Black-Scholes option-pricing model using the same assumptions as the~~

For stock options granted to employees with service-based vesting, ~~conditions was $0.4 million. As of March 31, 2018,~~ the ~~Company determined that the achievement of the requisite performance conditions was not probable and, as a result, no compensation cost was recognized for the performance contingent awards.~~

~~As of March 31, 2018 and 2017, there were 329,498 and 275,922 performance contingent stock option awards outstanding with a total~~ fair value of ~~$0.7 million~~stock options granted to employees was estimated on the date of grant using the Black-Scholes option pricing model and ~~$0.3 million respectively. As~~utilizing assumptions that were determined as follows:

Expected Term—The expected term represents the period that the options granted are expected to be outstanding and is determined using the simplified method (based on the mid-point between the vesting date and the end of ~~March 31, 2018 and 2017,~~the contractual term) as the Company ~~determined~~has concluded that ~~the achievement of the requisite performance conditions was not probable and, as a result, no compensation cost was recognized for these awards.~~

~~During the three months ended March 31, 2018, the Board of Directors granted performance and market contingent~~its stock option ~~awards exercisable for 160,727 shares of common~~exercise history does not provide a reasonable basis upon which to estimate expected term.

Expected Volatility—Due to limited historical data, the Company estimates stock ~~to certain members~~price volatility based on a combined weighted-average of the Company’s ~~executive team. These awards had~~historical average volatility and that of a ~~weighted average exercise~~selected peer group of comparable publicly traded companies within the biotechnology and pharmaceutical industry that were deemed to be representative of future stock price trends over the expected life of ~~$3.42, which was~~the award.

Risk-Free Interest Rate—The Company based the risk-free interest rate over the expected term of the options based on the ~~fair market value on~~constant maturity rate of U.S. Treasury securities with similar maturities as of the ~~grant~~ date ~~as determined by~~of the ~~Board of Directors.~~ grant.

Expected Dividends—The ~~total estimated grant-date fair value of these options was $0.7 million. Key assumptions~~Company has never paid any dividends and does not plan to pay dividends in the ~~valuation model included expected volatility, a risk-free interest rate,~~foreseeable future. Therefore, the expected dividend yield ~~and an expected term unique to the terms of these awards.~~is zero.

Under the performance and market contingent awards, 53,575 of the shares have three separate market triggers for vesting based upon (i) the closing of a financing where the Company sells shares of its equity securities to institutional investors at a minimum price per share, (ii) a change in control with aggregate proceeds payable to the Company’s common stock at a minimum price per share, or (iii) an initial public offering that becomes effective at a minimum specified price per share The remaining 107,152 shares have three separate market triggers for vesting

based upon (i) the closing of a financing where the Company sells shares of its equity securities to institutional investors at a minimum pre-money valuation, (ii) a change in control with a minimum aggregate proceeds payable to the Company’s common stock, or (iii) an initial public offering that becomes effective or an achievement of a minimum market capitalization, as measured by a trailing 30 day volume-weighted average price.

By definition, the market condition in these awards can only be achieved after the performance condition of a liquidity event has been achieved. As such, the requisite service period is based on the estimated period over which the market condition can be achieved. When a performance goal is deemed to be probable of achievement, time-based vesting and recognition of stock-based compensation expense commences. As of March 31, 2018, the Company determined that the achievement of the requisite performance conditions was not probable and, as a result, no compensation cost was recognized for these awards.

As of March 31, 2018 and 2017, there were 454,584 and 360,594 performance and market contingent stock option awards outstanding with a total fair value of $1.0 million and $0.4 million respectively. As of March 31, 2018 and 2017, the Company determined that the achievement of the requisite performance conditions was not probable and, as a result, no compensation cost was recognized for these awards.

~~A summary of the Company’s restricted stock activity for the three months ended March 31, 2018~~:

On May 4, 2023, and in accordance with the terms of the Company’s 2018 Plan, the Company’s Board of Directors approved a stock option repricing (the “Repricing”) for employees and certain service providers that were not affected by the reduction in its workforce, as well as affected employees and certain service providers entering into or subject to a continuing consulting agreement, as of May 11, 2023. Pursuant to the terms of the Repricing, the exercise price of each outstanding option to purchase shares of the Company's common stock granted under its 2018 Plan that had an original exercise price above $6.00, was reduced to an exercise price of $2.77, the closing price for the Company's common stock on May 11, 2023, the effective date of the Repricing.

On the effective date of the Repricing, 26 employees and certain service providers held 444,273 shares of the Company's common stock under option grants that met the eligibility criteria. Eligible outstanding options continue to remain outstanding in accordance with their current terms and conditions. On the effective date of the Repricing, the Company recognized $0.2 million of additional stock-based compensation from 251,821 shares of its common stock under vested options. The Company anticipates an additional $0.1 million will be expensed over the period from the effective date of the Repricing through 2025 relating to 192,452 shares of the Company's common stock under unvested options.

Since the Company was in a net loss position for all periods presented, basic net loss per common share is the same as diluted net loss per common share as the inclusion of all potential common shares outstanding would have been anti-dilutive.

Potentially dilutive securities that were not included in the diluted per share calculations because they would be anti-dilutive were as follows:

Up to ~~739,551~~3,390 shares may be contingently issued, if certain performance conditions are met under ~~our~~the Company’s in-licensing agreements.

Item 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OFOF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

You should read the following management’s discussion and analysis of our financial condition and results of operations in conjunction with our unaudited condensed ~~consolidated~~ financial statements and notes thereto included in Part I, Item 1 of this Quarterly Report on Form 10-Q and with our audited ~~consolidated~~ financial statements and notes thereto for the year ended December 31, ~~2017, included~~2022. Unless otherwise indicated, all information in this Quarterly Report on Form 10-Q gives effect to a 1-for-10 reverse stock split of our ~~prospectus dated May 2, 2018, filed with~~common stock that became effective on October 19, 2022, and all references to shares of common stock outstanding and per share amounts give effect to the ~~U.S. Securities and Exchange Commission (SEC) pursuant to Rule 424(b)(4) under the Securities Act of 1933, as amended (the “Prospectus”).~~reverse stock split.

We are a biotechnology company engaged in researching and developing therapeutics ~~with a mission~~ to ~~extend human healthspan, the period of time in one’s life unburdened by the~~slow, halt, or reverse diseases of aging. ~~Age-associated diseases cause considerable economic, personal~~Our initial focus is on creating senolytic medicines to selectively eliminate senescent cells and societal burden for individuals, their families and broader communities. Enabled by foundational scientific insights, we have devoted over six years to identifying multiple mechanisms that we believe to be root causes of age-associated disease. We are utilizing these insights to develop a broad portfolio of drug candidates tothereby treat ~~these~~ diseases of aging, such as ophthalmologic diseases.

In July 2020, we filed an Investigational New Drug application, or IND, to commence a Phase 1, first-in-human, open-label, single-ascending dose study of UBX1325 (foselutoclax) in patients with advanced diabetic macular edema, or DME, and ~~we expect~~neovascular age-related macular degeneration, or nAMD. Our goal with UBX1325 is to ~~initiate our first~~transformationally improve outcomes for patients with DME, nAMD, and diabetic retinopathy, or DR. In October 2020, the Phase 1, first-in-human, clinical study of ~~one~~UBX1325 commenced. That study, an open-label, single ascending dose clinical trial, evaluated doses from 0.5 – 10 µg administered as a single intra-vitreal injection in up to 8 patients with DME and 11 patients with nAMD all of whom had been off all anti-VEGF treatment due to lack of benefit for at least 6 months. The results of this study demonstrated acceptable safety and tolerability without any dose-limiting toxicities; no evidence of intraocular inflammation; and mean improvement in Best Corrected Visual Acuity (BCVA) of up to 9.5 ETDRS letters in those patients with DME receiving higher doses (5 and 10 µg) and a mean improvement in BCVA of 3.2 ETDRS letters in evaluable patients with nAMD at all doses, both at 24 weeks after treatment with UBX1325.

In May 2021, we initiated the Phase 2 BEHOLD study of UBX1325 in patients with DME and dosed our first patient in June 2021. This study was a multi-center, randomized, double-masked, sham-controlled study designed to evaluate the safety, tolerability, efficacy and durability of a single 10 µg dose of UBX1325 (foselutoclax) in patients with DME evaluated though 24 weeks. Patients had the option of rolling over to a 48-week long term extension and a majority of patients who completed their 24-week visits opted to remain in the study. A total of 65 patients were enrolled, randomized evenly between UBX1325 and sham-injected patients. These patients were being actively treated with anti-VEGF for at least 6 months prior to being randomized into the BEHOLD study (mean of 4.03 injections in the 6 months preceding randomization), and had persistent visual acuity deficits (73 ETDRS letters or worse, approximately 20/40 or worse, mean of 61.4 letters at baseline) and residual retinal fluid (≥300 µm of central subfield thickness on optical coherence tomography, mean of approximately 439.6 µm). At the time of randomization, patients were taken off of their anti-VEGF treatment, and instead treated with UBX1325 or a sham procedure. Endpoints explored in the study included safety and tolerability, changes in BCVA, CST, SRF/IRF, proportion of patients requiring rescue treatment, and durability of effects.

In August 2022, we announced positive 12- and 18-week data in our Phase 2 BEHOLD study, including that a single injection of UBX1325 led to a progressive, statistically significant, and clinically meaningful improvement in mean best-corrected visual acuity compared to sham treatment. At Week 18, the mean change from baseline of BCVA for UBX1325-treated subjects was an increase of 6.1 ETDRS letters that represented a difference of +5.0 ETDRS letters compared to sham-treated subjects (p=0.0368). In addition, patients treated with UBX1325 maintained central subfield thickness (CST) (+3.2 microns) compared to sham-treated patients who had progressive worsening (increase) in CST through 18 weeks (+53.5 microns) (p=0.0719).

In November 2022, we announced positive 24-week data in our BEHOLD study, showing that a single injection of UBX1325 led to a statistically significant and clinically meaningful improvement in BCVA of +6.2 ETDRS letters from baseline and +7.6 ETDRS letters compared to sham treatment (p=0.0084). Inclusive of rescue data, patients treated with UBX1325 had a mean improvement in BCVA of +6.4 ETDRS letters from baseline and +5.2 ETDRS letters compared to sham (p=0.0068). At 24 weeks, patients treated with UBX1325 had a mean change in CST of −5.4 microns from baseline compared to a worsening (increase) of +34.6 microns in sham-treated patients (p=0.1244). The proportion of rescue-free patients at 24 weeks was greater on UBX1325 (59.4%) as compared to

sham (37.5%) with fewer total rescues and longer time-to-rescue in UBX1325-treated patients as compared to sham. UBX1325 demonstrated a favorable safety and tolerability profile with no cases of intraocular inflammation, retinal artery occlusion, endophthalmitis, or vasculitis. Patients were followed through 48 weeks post-treatment in a long-term follow-up.

In April 2023, we announced positive 48-week data from this long-term follow-up in our BEHOLD study in 50 patients who participated in the 48-week extension study, showing that a single injection of UBX1325 led to a statistically significant and clinically meaningful improvement in vision lasting for the duration of the study (48 weeks), marked by a gain of +6.2 ETDRS letters from baseline, representing a difference of +5.6 ETDRS letters compared to sham-treated patients. In addition, patients treated with UBX1325 maintained stable CST compared to worsening in sham-treated patients (p=0.1198). Approximately 50% of UBX1325-treated patients did not require any additional injections through 48 weeks, compared to only 22% of patients in the sham arm. Retinal structure, as measured by central subfield thickness (CST), was maintained in UBX1325-treated patients throughout the duration of the study. UBX1325 continued to show a favorable safety and tolerability profile with no evidence of intraocular inflammation.

In June 2023, we announced the design of our ~~lead drug candidates~~Phase 2b of the ASPIRE clinical trial, which will evaluate UBX1325 head-to-head against aflibercept in previously treated patients with active DME who are not achieving optimal benefit from standard of care. We have activated clinical trial sites and are currently enrolling patients. In total, the ASPIRE study is expected to enroll about 40 subjects, with 16-week data readout expected in the ~~second~~fourth quarter of ~~2018.~~2024 and 24-week data expected in the first quarter of 2025.

The Phase 2b ASPIRE study in DME is a multi-center, randomized, double-masked, active-controlled study designed to evaluate the safety and efficacy of UBX1325 in comparison to aflibercept. Patients are expected to be randomized 1:1 to receive either 10 μg UBX1325, or 2 mg of aflibercept control injections every eight weeks for six months. We expect to enroll approximately 40 participants with DME who have residual visual acuity deficits and excess fluid in the retina despite having received at least three anti-VEGF injections in the preceding six months. All participants will receive three doses of 2 mg aflibercept as a “run-in” prior to randomization. The primary efficacy endpoint will be mean change from baseline in BCVA to week 24. Secondary endpoints will include change in BCVA over time, and CST change from baseline to week 24, and percentage of participants with one or more treatment-emergent ocular adverse events during the course of the study.

On age-related macular degeneration (AMD), in March 2022, we enrolled our first patient in the Phase 2 ENVISION study. In September 2022, the study completed enrollment of patients with nAMD who have had at least two intravitreal injections of anti-VEGF therapy in the preceding six months and who still have active choroidal neovascularization and residual sub- or intra-retinal fluid. Patients were to have received their last anti-VEGF treatment approximately 4-8 weeks prior to screening, and all patients were followed for approximately 24 weeks after dosing with either UBX1325 or aflibercept.

In March 2023, we announced 16-week and 24-week data in Part A of our ENVISION study, in which UBX1325 monotherapy did not achieve non-inferiority through 24 weeks due, in part, to an unexpected 3.5 letter gain at week two in the anti-VEGF control arm. UBX1325 maintained visual acuity in patients with ongoing active disease through 24 weeks with less than one letter mean decrease from baseline (−0.8 ETDRS letters at 24 weeks compared to +3.1 ETDRS letters in the aflibercept control arm). Of UBX1325-treated patients, 52% did not require anti-VEGF treatment through 24 weeks. UBX1325 demonstrated a favorable safety and tolerability profile with no cases of intraocular inflammation, retinal artery occlusion, endophthalmitis, or vasculitis.

In September 2023, we announced 48-week data in Part B of our ENVISION study, in which UBX1325 demonstrated a favorable safety and tolerability profile in the combination and monotherapy arms with no cases of significant intraocular inflammation, retinal artery occlusion or endophthalmitis. Patients switched from every 8-week aflibercept to a combination of aflibercept and UBX1325 at week 24 maintained vision gains achieved with aflibercept alone through week 48. Patients in a pre-specified subgroup with poor visual acuity at baseline (≤60 ETDRS letters) gained 3.2 ETDRS letters on combination treatment between weeks 24 and 48. In the UBX1325 monotherapy arm, patients maintained visual acuity for the duration of the study, with a mean change of +0.1 ETDRS letters at the 24-week time point and a mean change of −1.5 ETDRS letters at 48 weeks. 40% of UBX1325-treated patients did not need anti-VEGF rescue through 48 weeks and 64% of the patients achieved an anti-VEGF treatment-free period of over 24-weeks. The median time to first anti-VEGF rescue was 32 weeks.

In February 2022, and again on May 4, 2023, we announced restructuring actions to align resources to focus on our ongoing clinical programs and deliver on key development milestones. These actions to prioritize our ophthalmology programs, optimize resource allocation, extend our runway, and implement cost saving measures were designed to enable us to achieve multiple key clinical data readouts for UBX1325. As part of the May 2023 restructuring actions, we reduced our headcount by a total of nine employees, or approximately 29%, effective as of May 31, 2023, with three employees who departed as of June 30, 2023.

On November 9, 2023, we entered into an Inducement Letter with certain Holders of existing warrants to purchase up to an aggregate of 2,143,000 shares of common stock, which warrants were issued to the Holders on August 22, 2022, having an exercise price of $8.50 per share. The Holders agreed to exercise for cash their Existing Warrants to purchase an aggregate of 2,143,000 shares of common stock at a reduced exercise price of $2.045 per share in consideration of the Company’s agreement to issue New Warrants to purchase up to an aggregate of 2,143,000 shares of New Warrant Shares. Each New Warrant will have an exercise price equal to $1.92 per share. The Company expects to receive aggregate gross proceeds of approximately $4.38 million from the Exercise, before deducting placement agent fees and other offering expenses payable by the Company. We also agreed to issue to the Placement Agent Warrants to H.C. Wainwright & Co., LLC. to purchase up to 128,580 shares of common stock with an exercise price equal to $2.5563 per share. We expect to use the net proceeds from the Exercise for working capital, operating expenses to include clinical trial progression, and general corporate purposes. The closing of the transactions contemplated pursuant to the Inducement Letter is expected to occur on or about November 14, 2023, subject to satisfaction of customary closing conditions.

Since the commencement of our operations, we have invested a significant portion of our efforts and financial resources in research and development activities, and we have incurred net losses each year since inception. Our net losses were ~~$16.1~~$15.3 million and ~~$8.9~~$13.7 million for the three months ended ~~March 31, 2018~~September 30, 2023 and ~~2017,~~2022, respectively, and $38.4 million and $45.8 million for the nine months ended September 30, 2023 and 2022, respectively. We do not have any products approved for sale, and we have never generated any ~~revenue from contracts with customers.~~product revenue. As of ~~March 31, 2018,~~September 30, 2023, we had an accumulated deficit of ~~$103.0~~$498.3 million, and we do not expect positive cash flows from operations in the foreseeable future.

Substantially all of our net losses have resulted from costs incurred in connection with our research and development programs and from general and administrative costs associated with our operations. Based on our current operating plans and following the cash exercise by certain holders of existing warrants, we expect our existing capital resources will fund our planned operating expenses into the third quarter of 2025, which will be used to advance UBX1325. We will need to raise additional capital; however, adequate funding may not be available to us on acceptable terms, or at all, particularly in light of the current economic uncertainty, high interest rates, rising inflation, the government closure of Silicon Valley Bank and liquidity concerns at other financial institutions, and the potential for local and/or global economic recession. We expect to continue to look for opportunities to secure such financing in the near future, in addition to using our existing 2022 ATM Offering Programs (as defined below).If sufficient funds on acceptable terms are not available when needed, we could be required to significantly reduce our operating expenses and delay, reduce the scope of, or eliminate one or more of our development programs.

We expect to continue to incur net operating losses for at least the next several years as we continue our research and development efforts, advance our drug candidates through preclinical and clinical development, seek regulatory approval, prepare for and, if approved, proceed to commercialization.

Prior to our initial public offering, or IPO, we had funded our operations primarily from the issuance and sale of convertible preferred stock and convertible promissory notes. In May 2018, we completed our IPO pursuant to which we issued 5,000,000 shares of our common stock at a price of $17.00 per share. We received net proceeds of $76.1 million from the IPO.

We do not expect to generate revenue from any drug candidates that we develop until we obtain regulatory approval for one or more of such drug candidates and commercialize our products or enter into collaborative agreements with third parties. Substantially all of our net losses have resulted from costs incurred in connection with our research and development programs and from general and administrative costs associated with our operations. As a result, we will need to raise additional capital. If sufficient funds on acceptable terms are not available when needed, we could be required to significantly reduce our operating expenses and delay, reduce the scope of, or eliminate one or more of our development programs.

We rely on third parties in the conduct of our preclinical studies and clinical trials and for manufacturing and supply of our drug candidates. We have no internal manufacturing capabilities, and we will continue to rely on third parties, many of whom are single-source suppliers, for our preclinical and clinical trial materials, as well as the commercial supply of our products. In addition, we do not yet have a marketing or sales organization or commercial infrastructure. Accordingly, we will incur significant expenses to develop a marketing and sales organization and commercial infrastructure in advance of generating any product sales.

Although the effects continue to diminish, should there be a resurgence in the COVID-19 pandemic and place significant strains on the providers of healthcare services, including the healthcare institutions, clinical research

Research and development expenses consist primarily of costs incurred for the development of our drug candidates, which include:

We expect our research and development expenses to increase ~~substantially in the future~~ as we advance our drug candidates into and through preclinical and clinical trials and pursue regulatory approval of our drug candidates. The process of conducting the ~~necessary~~ clinical trials required to obtain regulatory approval is costly and time-consuming. Clinical trials generally become larger and more costly to conduct as they advance into later stages and ~~in the future,~~ we ~~will be~~are required to make estimates for expense accruals related to clinical trial expenses. The actual probability of success for our drug candidates may be affected by a variety of factors including: the safety and efficacy of our drug candidates, early clinical data, investment in our clinical program, the ability of collaborators, if any, to successfully develop any drug candidates we license to them, competition, manufacturing capability and commercial viability. We may never succeed in achieving regulatory approval for any of our drug candidates. ~~Due to the early-stage nature of our lead programs, we do not track~~Program costs that are direct external expenses are tracked on a ~~project-by-project basis. As our programs~~program-by-program basis once they enter clinical ~~studies, we intend to track the cost of each program.~~studies. As a result of the uncertainties discussed above, we are unable to determine the duration and completion costs of our research and development projects or when and to what extent we will generate revenue from the commercialization and sale of our drug candidates.

Our general and administrative expenses consist primarily of personnel costs, allocated facilities costs and other expenses for outside professional services, including legal, audit and accounting services, and depreciation and amortization expense related to property and equipment. Personnel costs consist of salaries, benefits, severance, and stock-based compensation. We expect to continue to incur additional expenses associated with operating as a public company, including expenses related to compliance with the rules and regulations of the Securities and Exchange Commission and standards applicable to companies listed on a national securities exchange, additional insurance expenses, investor relations activities, and other administrative and professional services. ~~We also expect to increase the size of our administrative headcount to support the growth of our business and operate as a public company.~~

Interest income is primarily related to interest earned on our marketable ~~securities for~~securities.

Interest expense relates to interest on the ~~three~~Loan Agreement entered into on August 3, 2020.

Other expense during the nine months ended ~~March 31, 2018~~September 30, 2023 includes property and ~~2017.~~ other taxes partially offset by gains on sale of laboratory equipment and the debt extinguishment loss associated to the unamortized debt discount. Other income during the nine months ended September 30, 2022 includes the recognized gains resulting from the extinguishment of the derivative related to long term debt.

Comparison of the Three and Nine Months Ended ~~March 31, 2018~~September 30, 2023 and ~~2017~~2022

The following table sets forth the significant components of our results of ~~operations:~~operations (in thousands):

	Three Months Ended March 31,
	2018			2017			Increase/ (Decrease)		Three Months Ended September 30,									Nine Months Ended September 30,
	(in thousands)								2023			2022			Change			2023			2022			Change
Summary of Operations Data:
Licensing revenue - related party									$	—		$	—		$	—		$	—		$	236		$	(236	)
Operating expenses:
Research and development		13,025			6,970			6,055		4,901			8,208			(3,307	)		17,266			28,222			(10,956	)
General and administrative		3,457			2,070			1,387		4,428			4,922			(494	)		14,681			15,669			(988	)
Impairment of long-lived assets										5,602			—			5,602			5,602			—			5,602
Total operating expenses		16,482			9,040			7,442		14,931			13,130			1,801			37,549			43,891			(6,342	)
Loss from operations		(16,482	)		(9,040	)		7,442		(14,931	)		(13,130	)		(1,801	)		(37,549	)		(43,655	)		6,106
Interest income		352			108			244		689			329			360			2,349			416			1,933
Other expense, net		(3	)		(2	)		1
Interest expense										(470	)		(866	)		396			(2,451	)		(2,568	)		117
Other income (expense), net										(577	)		(41	)		(536	)		(711	)		49			(760	)
Net loss	$	(16,133	)	$	(8,934	)	$	7,199	$	(15,289	)	$	(13,708	)	$	(1,581	)	$	(38,362	)	$	(45,758	)	$	7,396

Research and development expenses ~~increased~~decreased by ~~$6.0~~$3.3 million to ~~$13.0~~$4.9 million for the three months ended ~~March 31, 2018~~September 30, 2023 from ~~$7.0~~$8.2 million for the three months ended ~~March 31, 2017.~~September 30, 2022. The ~~increase~~decrease was primarily due to ~~an increase~~decreases of $1.0 million in personnel costs due to our reduced headcount related to our reduction in force, $2.0 million in direct research and development expenses mainly due to the completion of the Phase 2 BEHOLD study of UBX1325 in patients with DME and the near completion of the Phase 2 ENVISION study of UBX1325 in patients with AMD, and $0.3 million in operating costs due to reduced fixed assets depreciation and reduced office space.

Research and development expenses decreased by $10.9 million to $17.3 million for the nine months ended September 30, 2023 from $28.2 million for the nine months ended September 30, 2022. The decrease was primarily due to decreases of $5.4 million in personnel costs due to lower severance and retention expenses paid as well as reduced headcount in the nine months ended September 30, 2023, $3.6 million ~~for personnel related~~in direct research and development expenses ~~$1.5 million for sponsored research expenses~~mainly due to the completion of the BEHOLD study and ~~$0.9~~near completion of the ENVISION study, $1.7 million in ~~pre-clinical~~operating costs due to sublease income from our facilities, and ~~clinical expenses~~$0.3 million in ~~preparation of the Company’s first Phase 1 study.~~laboratory supplies.

General and administrative expenses ~~increased~~decreased by ~~$1.4~~$0.5 million, to ~~$3.5~~$4.4 million for the three months ended ~~March 31, 2018~~September 30, 2023 from ~~$2.0~~$4.9 million for the three months ended ~~March 31, 2018.~~September 30, 2022. The ~~increase~~decrease was primarily due to ~~an increase~~decreases of $0.5 million in personnel-related expenses due to reduced headcount and the higher bonus and severance amounts paid in 2022, and $0.3 million in professional fees and accounting service fees, partially offset by $0.3 million increase in operating costs mainly from the discontinuation of sublease income generated from the former Brisbane property.

General and administrative expenses decreased by $1.0 million, to $14.7 million for the nine months ended September 30, 2023 from $15.7 million for the nine months ended September 30, 2022. The decrease was primarily due to a decrease of $1.6 million in personnel-related expenses due to the higher severance and retention expenses paid during the nine months ended September 30, 2022, as well as reduced headcount in the nine months ended September 30, 2023, partially offset by an increase of $0.6 million ~~and $0.8 million~~ in professional ~~services expenses in preparation~~fees and external consultants.

As a ~~public company.~~result of subleasing our South San Francisco facility through June 30, 2026, we determined an impairment indicator was present. During the three and nine months ended September 30, 2023, we recognized a non-cash impairment charge of $5.6 million, which consisted of $4.0 million for the operating lease right-of-use asset and $1.6 million for the related leasehold improvements for our subleased South San Francisco facility.

~~Our~~For the three and nine months ended September 30, 2023, our interest income was $0.7 million and $2.4 million, respectively. For the three and nine months ended September 30, 2022, our interest income was $0.3 million and ~~$0.1~~$0.4 million, respectively. The increase is primarily attributable to higher market yields on our cash equivalents and marketable securities.

Our interest expense was $0.5 million and $0.9 million for the three months ended ~~March 31, 2018~~September 30, 2023 and ~~March 31, 2017~~2022, respectively, asand $2.5 million and $2.6 million for the nine months ended September 30, 2023 and 2022, respectively, related to the Loan Agreement which was paid off in the three months ended September 30, 2023.

Other expense, net, was $0.6 million and $0.7 million for the three and nine months ended September 30, 2023, respectively, and was primarily due to the extinguishment loss from unamortized debt discount expenses for property and other taxes partially offset by gains on sale of laboratory equipment in either period. Other expense, net, was insignificant for the three months ended September 30, 2022 while other income, net, was insignificant for the nine months ended September 30, 2022. During the nine months ended September 30, 2022, we ~~invested our cash~~recognized a $0.2 million gain from extinguishment of debt upon conversion to equity and $0.1 million in ~~marketable securities.~~net gain from the sale of assets, which was partially offset by $0.2 million in property and other taxes.

We have incurred net losses each year since inception. We do not have any products approved for sale and have never generated any revenue from product sales. Historically, we have incurred operating losses as a result of ongoing efforts to develop our drug candidates, including conducting ongoing research and development, preclinical studies and providing general and administrative support for these operations. Our net losses were $15.3 million and $13.7 million for the three months ended September 30, 2023 and 2022, respectively, and $38.4 million and $45.8 million for the nine months ended September 30, 2023 and 2022, respectively. As of ~~March 31, 2018,~~September 30, 2023, we had an accumulated deficit of ~~$103.0~~$498.3 million, and we do not expect positive cash flows from operations in the foreseeable future. We effectuated a reduction in expenditures including a 29% reduction in force and reduced clinical program spend related to our Tie2 bispecific program. Our future viability is dependent on its ability raise additional capital to finance its operations. Although we have been successful in raising capital in the past, there is no assurance that we will be successful in obtaining such additional financing. If sufficient funds on acceptable terms are not available when needed, we could be further required to significantly reduce its operating expenses and delay, reduce the scope of, or eliminate one or more of our development programs. Failure to manage discretionary spending or raise additional financing, as needed, may adversely impact our ability to achieve our intended business objectives. We expect that our cash, cash equivalents, and marketable securities will be sufficient to fund our operations for a period of at least one year from the date the accompanying Financial Statements are filed with the Securities and Exchange Commission. Based on our current operating plans and following the cash exercise by certain holders of existing warrants, we expect our existing capital resources will fund our planned operating ~~losses~~expenses into the third quarter of 2025, which will be used to advance UBX1325.

As a result, we will need to raise additional capital to finance its operations. Adequate funding may not be available to us on acceptable terms, or at all, particularly in light of the economic uncertainty, liquidity concerns at financial institutions, and ~~net~~potential for local and/or global economic recession. Further, if banks and financial institutions enter receivership or become insolvent in the future in response to financial conditions affecting the banking system and financial markets, our ability to access our existing cash, ~~used in~~cash equivalents and marketable securities may be threatened, which could have a material adverse effect on our business and financial condition.

Further, based on our public float, as of the date of the filing of this Quarterly Report on Form 10-Q, we are only permitted to utilize a shelf registration statement, including the registration statements under which our ATM Offering Programs are operated, subject to Instruction I.B.6 to Form S-3, which is referred to as the “baby shelf” rule. For so long as our public float is less than $75.0 million, we may not sell more than the equivalent of one-third of our

public float during any 12 consecutive months pursuant to the baby shelf rules. Although alternative public and private transaction structures may be available, these may require additional time and cost, may impose operational restrictions on us, and may not be available on attractive terms. If sufficient funds on acceptable terms are not available when needed, we could be required to significantly reduce our operating ~~activities~~ ~~will increase over at least~~expenses and delay, reduce the ~~next several years~~scope of, or eliminate one or more of our development programs. Failure to manage discretionary spending or raise additional financing, as needed, may adversely impact our ability to achieve our intended business objectives because without substantial additional capital, we ~~continue our research and development activities,~~may not be able to complete pivotal trials necessary to advance our ~~drug candidates through preclinical~~product development and ~~clinical testing and move into later and more costly stages of drug development, hire personnel and prepare for regulatory submissions and the commercialization of~~ our ~~drug candidate~~s.programs.

We have historically financed our operations primarily through ~~issuance and sale~~private placements of ~~convertible~~ preferred stock and ~~convertible~~ promissory notes, as well as public equity issuances, such as our initial public offering, and more recently through proceeds from our Loan Agreement, our prior and existing at-the-market offering programs, the Equity Purchase Agreement, and the sale of common stock and warrants in the Follow-On Offering (each as defined below) and we will continue to be dependent upon equity and/or debt financing to operate our business until we are able to generate positive cash flows from our operations.

In August 2020, we entered into a Loan and Security Agreement (as amended, restated, supplemented or otherwise modified, the "Hercules Loan Agreement") with Hercules Capital, Inc. (“Hercules”), as administrative agent and collateral agent for the lenders, and certain banks and other financial institutions or entities from time to time parties thereto, for an aggregate principal amount of up to $80.0 million secured term loan facility (the "Hercules Facility") subject to certain terms and conditions. $25.0 million was advanced to us on the date of execution of the Hercules Loan Agreement. In August 2022, we met certain clinical and capital raising milestones, which extended the interest only period to March ~~2018,~~2023. On January 25, 2023, we ~~sold 3,590,573~~entered into a second amendment to the Hercules Loan Agreement whereas the amortization date was extended from March 1, 2023 to April 1, 2023. As such, we continued to make interest only payments up to the amended amortization date and were required to repay the principal balance and interest in equal monthly installments through August 1, 2024. In December 2021, we entered into an amendment to the Hercules Loan Agreement under the terms of which, Hercules (including any of its assignees) had the option for a period of six (6) months to convert up to $5.0 million of the outstanding principal under the existing loan into shares of ~~Series C convertible preferred stock at $15.3317 per share for proceeds~~our common stock. Under this amendment, the required cash reserve amount would be reduced by the principal amount of ~~$54.9~~the converted loan to not less than $10 million. As of ~~March~~December 31, ~~2018,~~ 2022, we had ~~$134.6 million in cash, cash equivalents and marketable securities. In April 2018, we sold 322,852~~issued 435,497 shares of ~~Series C convertible preferred~~our common stock ~~at $15.3317 per share~~reducing our outstanding loan principal balance by $5.0 million and reducing the required cash reserve to $10 million. In addition, the interest-only period could extend an additional three months to June 1, 2023 if specific milestones related to our clinical trials and raising additional capital by April 1, 2023 were met; however, we did not meet all these criteria such that the amortization date remained April 1, 2023. There were no material adverse events in connection with the Hercules Loan Agreement.

On September 6, 2023, we and Hercules entered into a payoff letter for ~~additional~~a voluntary prepayment with respect to the Hercules Loan Agreement (the "Payoff Letter"). Pursuant to the Payoff Letter, we paid a total of $15.0 million to Hercules, representing the outstanding principal, accrued and unpaid interest, fees, costs and expenses due to Hercules under the Hercules Facility and the Hercules Loan Agreement and related loan documents, in repayment of our outstanding obligations under the Hercules Facility and the Hercules Loan Agreement and related loan documents, and thereby terminated the Hercules Loan Agreement and the Hercules Facility and related loan documents.

In March 2022, we filed the March 2022 Shelf Registration Statement and entered into the March 2022 Sales Agreement, as amended, with Cowen as sales agent to sell shares of our common stock, from time to time, with aggregate gross sales proceeds of ~~$5.0 million. In May 2018,~~up to $25.0 million pursuant to the March 2022 Shelf Registration Statement as an “at-the-market” offering under the Securities Act. Cowen is entitled to up to 3.0% of the gross proceeds of any shares of common stock sold under the March 2022 Sales Agreement. During the nine months ended September 30, 2023, there were 274,781 shares of our common stock sold pursuant to the March 2022 Sales Agreement and we ~~consummated our initial public offering and~~ received total net proceeds of ~~$76.1~~approximately $1.0 million, after deducting ~~underwriting discounts,~~ commissions and other offering expenses ~~payable by us.~~that were insignificant.

On August 22, 2022, we closed an underwritten offering, or the Follow-On Offering, in which we issued and sold an aggregate of 6,428,571 shares of common stock together with warrants (the "Warrants"), to purchase an up to aggregate of 6,428,572 shares of common stock at an aggregate offering price of $7.00 per unit. The Warrants have an exercise price of $8.50 per share underlying the Warrant. The net proceeds to us were approximately $41.7 million.

In October 2022, we filed the October 2022 Shelf Registration Statement and also entered into the October 2022 Sales Agreement with Cowen as sales agent to sell shares of our common stock, from time to time, with aggregate gross sales proceeds of up to $50.0 million pursuant to the October 2022 Shelf Registration Statement as an “at-the-market” offering under the Securities Act. Cowen is entitled to up to 3.0% of the gross proceeds of any shares of common stock sold under the October 2022 Sales Agreement. There were no shares sold under the October 2022 ATM Offering Program during the nine months ended September 30, 2023.

In September 2021, we entered into a Purchase Agreement with Lincoln Park Capital Fund, LLC, under which we may at our discretion, sell up to $30.0 million shares of our common stock over a 36-month period, subject to certain daily limits, applicable prices, and conditions. During the first quarter of 2022, we had initiated the purchase of 0.1 million shares of our common stock amounting to $0.9 million in gross proceeds. There were no purchases initiated in the remaining three quarters of 2022. Issuances under the Purchase Agreement were to be made pursuant to our Registration Statement filed in July 2019, which has since expired. We would need to file a new prospectus supplement covering issuances under the Purchase Agreement in order to continue using the facility.

To date we have not generated any ~~revenue for contracts with customers and have only received a contribution from a third party organization for certain research and development activities to support their philanthropic mission.~~product revenue. We expect to continue to incur significant losses for the foreseeable future, and we expect the losses to increase as we continue the development of, and seek regulatory approvals for, our drug candidates, and begin to commercialize any approved products. We are subject to all of the risks typically related to the development of new drug candidates, and we may encounter unforeseen expenses, difficulties, complications, delays, and other unknown factors that may adversely affect our business. Moreover, ~~following the completion of our IPO,~~since becoming a public company, we ~~expect~~continue to incur additional ongoing costs associated with operating as a public company. We anticipate that we will need substantial additional funding in connection with our continuing operations.

Until we can generate a sufficient amount of revenue from the commercialization of our drug candidates or from collaborative agreements with third parties, if ever, we expect to finance our future cash needs through ~~public or private equity or debt financings.~~various means. We do not have any committed external source of funds. Additional capital may be raised through the sale of our equity securities through our ATM Offering Programs or otherwise, incurring debt, entering into licensing or collaboration agreements with partners, receiving research contributions, grants or other sources of financing to fund our operations. There can be no assurance that sufficient funds will be available to us on attractive terms or at all. If we are unable to obtain additional funding from these or other sources, it may be necessary to significantly reduce our rate of spending through reductions in staff and delaying, scaling back, or stopping certain research and development programs. Insufficient liquidity may also require us to relinquish rights to drug candidates at an earlier stage of development or on less favorable terms than we would otherwise choose.

Since our inception, we have incurred significant losses and negative cash flows from operations. We have an accumulated deficit of $103.0 million through March 31, 2018. We expect to incur substantial additional losses in the future as we conduct and expand our research and development activities. We believe that our existing cash, cash equivalents and marketable securities will be sufficient to enable us to fund our projected operations through at least the next 12 months. We expect our existing capital resources together with the proceeds from our IPO will fund our planned operating expenses into 2021, including through clinical data readout from our Phase 1 clinical study of UBX0101 and data readouts from two additional Phase 1 clinical studies of our lead programs for ophthalmologic and pulmonary disorders.

We have based our projections of operating capital requirements on assumptions that may prove to be incorrect and we may use all our available capital resources sooner than we expect. Because of the numerous risks and uncertainties associated with research, development, and commercialization of biotechnology products, we are unable to estimate the exact amount of our operating capital requirements. Our future funding requirements will depend on many factors, including, but not limited to:

The following table sets forth a summary of the primary sources and uses of cash, cash equivalents and restricted cash for each of the periods presented ~~below:~~below (in thousands):

Cash used in operating activities of ~~$11.9~~$29.5 million for the ~~three~~nine months ended ~~March 31, 2018~~September 30, 2023 consisted primarily of a net loss of ~~$16.0~~$38.4 million, ~~which was offset by~~adjusted for net non-cash charges of ~~$1.5~~$12.4 million and ~~$2.6 million~~changes in net operating assets and ~~liabilities.~~liabilities of $3.6 million. Our non-cash charges consisted primarily ~~consisted~~ of ~~$1.4~~$6.7 million in stock-based ~~compensation.~~compensation, $5.6 million in impairment of long-lived assets, $0.9 million in depreciation and amortization, $0.7 million in amortization of debt issuance costs and $0.5 million in debt extinguishment loss, partially offset by $1.2 million in premium and discounts on marketable securities and $0.8 million in non-cash rent expense. The net change in our ~~net~~ operating assets and liabilities ~~was~~consisted primarily ~~due to an increase in contribution receivable~~ of ~~$1.4 million related to contribution revenue received, increase in accounts payable~~decreases of $1.9 million ~~due to the increase in overall research and development activities, increase~~ in prepaid expenses and other current assets, ~~of $.03~~$0.8 million ~~due to ongoing amortization of prepaid expenses and a decrease~~ in accrued compensation, ~~of $1.2~~$0.6 million ~~due to the payment of annual bonuses.~~in accounts payable and $0.3 million in accrued liabilities and other current liabilities.

Cash used in operating activities of ~~$7.9~~$40.7 million for the ~~three~~nine months ended ~~March 31, 2017~~September 30, 2022 consisted primarily of a net loss of ~~$8.9~~$45.8 million, ~~which was partially offset by~~adjusted for net non-cash charges of ~~$0.4~~$7.7 million and ~~an increase~~changes in ~~our~~ net operating assets and liabilities of ~~$0.7~~$2.6 million. Our non-cash charges consisted primarily ~~consisted~~ of ~~$0.4~~$7.1 million in stock-based ~~compensation.~~compensation, $1.8 million in depreciation and amortization, $1.0 million amortization of debt issuance costs and $0.2 million in premium and discounts on marketable securities, partially offset by $1.9 million in non-cash rent expense, $0.3 million in gain from disposal of property and equipment, and $0.2 million in gain from extinguishment of debt upon conversion to equity. The net change in our ~~net~~ operating assets and liabilities ~~was due~~consisted primarily ~~due to an increase in accounts payable~~ of ~~$1.2~~decreases of

$1.4 million ~~due to the increase in overall research and development activities and a decrease~~ in prepaid expenses and other current assets, $1.1 million in accrued compensation, and $0.6 million in accrued liabilities and other current liabilities, partially offset by an increase of ~~$0.3~~$0.5 million ~~primarily related to interest receivable from short and long term marketable securities.~~in accounts payable.

Cash provided by investing activities of ~~$12.9~~$45.4 million for the ~~three~~nine months ended ~~March 31, 2018~~September 30, 2023 was related to the maturities of marketable securities of $74.0 million, partially offset by purchases of marketable securities of ~~$6.2 million and purchases of property and equipment of $0.1 million, which were partially offset by maturities of marketable securities of $19.3~~$28.6 million.

Cash used in investing activities of ~~$59.5~~$24.4 million for the ~~three~~nine months ended ~~March 31, 2017~~September 30, 2022 was related to the purchases of marketable securities of ~~$59.2~~$86.6 million and ~~the purchases~~property and equipment of $0.1 million, partially offset by maturities of marketable securities of $62.0 million and proceeds from sale of property and equipment of $0.3 million.

Cash used in financing activities of $20.7 million for the nine months ended September 30, 2023 was primarily related to the $20.0 million principal repayment of our long-term debt and $1.6 million of term loan issuance costs, partially offset by $0.8 million proceeds, net of issuance costs, from the sale of common stock through our March 2022 ATM Offering Program and $0.1 million proceeds from issuance of common stock under the 2018 ESPP.

Cash provided by financing activities of ~~$54.4~~$54.7 million for the ~~three~~nine months ended ~~March 31, 2018~~September 30, 2022 was primarily related to $41.7 million proceeds, net of issuance costs, from the sale of common stock and accompanying warrants in the Follow-On Offering, $12.0 million proceeds, net of issuance costs, from the sale of common stock through our March 2022 ATM Offering Program and our prior at-the-market ATM offering programs, $0.9 million proceeds, net of issuance costs, from issuance of common stock to Lincoln Park Capital Fund and $0.1 million proceeds from ~~the~~ issuance of ~~Series C convertible preferred~~common stock ~~if $54.9 million offset by payments of deferred offering costs in relation to our planned IPO of $0.6 million.~~under the 2018 ESPP.

Cash provided by financing activities of $8.0 million for the three months ended March 31, 2017 was primarily related to net proceeds of $8.0 million from the issuance of shares of our Series B convertible preferred stock.

Our contractual obligations and commitments relate primarily to our Loan Agreement, operating leases and non-cancelable purchase obligations under agreements with various research and development organizations and suppliers in the ordinary course of business. See Note 8, “Commitments and Contingencies” and Note 9, “Term Loan Facility” to our financial statements for further information.

We are party to various license agreements pursuant to which we have in-licensed rights to various technologies, including patents, research “know-how” and proprietary research tools, for the discovery, research, development and commercialization of drug candidates to treat age-related diseases. The license agreements obligate us to make certain milestone payments related to specified clinical development and sales milestone events, as well as tiered royalties in the low-single digits based on sales of licensed products. See Note 6, “License Revenue and Agreements” to our financial statements for additional information.

In the normal course of business, we enter into contracts and agreements that contain a variety of representations and warranties and provide for general indemnifications. Our exposure under these agreements is unknown because it involves claims that may be made against us in the future but have not yet been made. To date, we have not paid any claims or been required to defend any action related to our indemnification obligations. However, we may record charges in the future as a result of these indemnification obligations.

In accordance with our certificate of incorporation and bylaws, we have potential indemnification obligations to our officers and directors for specified events or occurrences, subject to some limits, while they are serving at our request in such capacities. There have been no ~~material changes outside the ordinary course~~claims to date, and we have director and officer insurance that may enable us to recover a portion of ~~business related to our contractual obligations during the three months ended March 31, 2018 as compared to those disclosed in our Prospectus, filed with the SEC on May 4, 2018.~~ any amounts paid for future potential claims.

We have not entered into any off-balance sheet arrangements. ~~While we have an investment classified as variable interest entity, its purpose is not to provide off-balance sheet financing.~~

There have been no material changes to our critical accounting policies and estimates during the ~~three~~nine months ended ~~March 31, 2018~~September 30, 2023 as compared to those disclosed in our ~~Prospectus, filed with~~Annual Report on Form 10-K for the ~~SEC on May 4, 2018.~~ year ended December 31, 2022, other than as provided in Note 2 to our condensed financial statements, “Summary of Significant Accounting Policies.”

See Note 2 to our ~~Financial Statements~~condensed financial statements, “Summary of Significant Accounting ~~Policies”~~Policies,” for information.

We are an emerging growth company, as defined in the JOBS Act. Under the JOBS Act, emerging growth companies can delay adopting new or revised accounting standards issued subsequent to the enactment of the JOBS Act until such time as those standards apply to private companies. We have irrevocably elected to avail ourselves of this exemption from new or revised accounting standards and, therefore, will not be subject to the same new or revised accounting standards as other public companies that are not emerging growth companies. We also rely on other exemptions provided by the JOBS Act, including, without limitation, providing an auditor’s attestation report on our system of internal controls over financial reporting pursuant to Section 404(b) of the Sarbanes-Oxley Act. We will remain an emerging growth company until the earlier of (1) the last day of the year following the fifth anniversary of the consummation of our IPO, (2) the last day of the year in which we have total annual gross revenue of at least $1.235 billion, (3) the last day of the year in which we are deemed to be a “large accelerated filer” as defined in Rule 12b-2 under the Exchange Act, which would occur if the market value of our common stock held by non-affiliates exceeded $700.0 million as of the last business day of the second fiscal quarter of such year or (4) the date on which we have issued more than $1.0 billion in non-convertible debt securities during the prior three-year period. Even after we no longer qualify as an emerging growth company, we may still qualify as a “smaller reporting company” which may allow us to take advantage of many of the same exemptions from disclosure requirements including not being required to comply with the auditor attestation requirements of Section 404(b) of the Sarbanes-Oxley Act.

We expect that we will no longer qualify as an emerging growth company after December 31, 2023, at which time we will become subject to certain disclosure and compliance requirements as discussed herein that apply to other public companies but that did not previously, or currently, apply to us due to our status as an emerging growth company.

~~There have been no material changes~~Cash, Cash Equivalents, and Marketable Securities

We are exposed to ~~our~~ market risks in the ordinary course of our business. These risks primarily relate to interest rate sensitivities. We had cash, cash equivalents, and marketable securities of $45.9 million as of September 30, 2023, which consist of bank deposits, money market funds, and marketable securities. The primary objective of our investment activities is to preserve capital to fund our operations. We also seek to maximize income from ~~those disclosed~~our investments without assuming significant risk. Because our investments are primarily short-term in duration, we believe that our ~~Prospectus, filed with~~exposure to interest rate risk is not significant, and a 1% movement in market interest rates would not have a significant impact on the ~~SEC on May 4, 2018.~~ total value of our portfolio.

Our management, with the participation of our chief executive and financial officers, evaluated the effectiveness of our disclosures controls and procedures, as defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act, as of ~~March 31, 2018.~~September 30, 2023. The term “disclosure controls and procedures,” as defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act, means controls and other procedures of a company that are designed to ensure that information required to be disclosed by a company in the reports that it files or submits under the Exchange Act is recorded, processed, summarized and reported within the time periods specified in the SEC’s rules and forms. Disclosure controls and procedures include, without limitation, controls and procedures designed to ensure that information required to be disclosed by a company in the reports that it files or submits under the Exchange Act is accumulated and communicated to ~~the company’s~~ management, including its principal executive and principal financial officers, as appropriate, to allow timely decisions regarding required disclosure. Management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving their objectives and management necessarily applies its judgment in evaluating the cost-benefit relationship of possible controls and procedures. Based on the evaluation of our disclosure controls and procedures as of ~~March 31, 2018,~~September 30, 2023, our chief executive officer and chief financial officer concluded that, as of such date, our disclosure controls and procedures were effective at a reasonable assurance level.

Management determined that, as of ~~March 31, 2018,~~September 30, 2023, there were no changes in our internal control over financial reporting that occurred during the fiscal quarter then ended that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

We are not currently a party to any material litigation or other material legal proceedings.

This Quarterly Report on Form 10-Q contains “forward-looking statements” within the meaning of Section 21E of the Securities Exchange Act of 1934, as amended, or the Exchange Act. All statements other than statements of historical facts contained in this Quarterly Report on Form 10-Q are statements that could be deemed forward-looking ~~information~~statements reflecting the current beliefs and expectations of management with respect to future events or to our future financial performance and involve known and unknown risks, uncertainties, and other factors that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by these forward-looking statements. These statements are often identified by the use of words such as “aim,” “anticipate,” “assume,” “believe,” “contemplate,” “continue,” “could,” “due,” “estimate,” “expect,” “goal,” “if,” “intend,” “may,” “objective,” “plan,” “predict,” “potential,” “positioned,” “seek,” “should,” “target,” “will,” “would,” “until,” and similar expressions or variations. Forward-looking statements contained in this Quarterly Report on Form 10-Q include, but are not limited to, statements about:

We caution you that the foregoing list may not contain all of the forward-looking statements made in this Quarterly Report on Form 10-Q. Forward-looking statements involve known and unknown risks, uncertainties and other factors that may cause our actual results, performance or achievements to be materially different from any future results, performance, or achievements expressed or implied by the forward-looking statements. We discuss these risks in greater detail in “Risk Factors” and elsewhere in this Quarterly Report on Form 10-Q. Given these uncertainties, you should not place undue reliance on these forward-looking statements. Also, forward-looking statements represent our management’s beliefs and assumptions only as of the date of this Quarterly Report on Form 10-Q. Except as required by law, we assume no obligation to update these forward-looking statements publicly, or to update the reasons actual results could differ materially from those anticipated in these forward-looking statements, even if new information becomes available in the future. This Quarterly Report on Form 10-Q also contains estimates, projections, and other information concerning our industry, our business and the markets for certain drugs, including data regarding the estimated size of those markets, their projected growth rates, and the incidence of certain medical conditions. Information that is based on estimates, forecasts, projections or similar methodologies is inherently subject to ~~many risks~~uncertainties, and ~~our~~ actual ~~results~~events or circumstances may differ materially from events and circumstances reflected in this information. Unless otherwise expressly stated, we obtained this industry, business, market, and other data from reports, research surveys, studies, and similar data prepared by third parties, industry, medical and general publications, government data, and similar sources. In some cases, we do not expressly refer to the sources from which this data is derived. In that regard, when we refer to one or more sources of this type of data in any ~~forward-looking statements made by~~paragraph, you should assume that other data of this type appearing in the same paragraph is derived from the same sources, unless otherwise expressly stated or ~~on behalf~~the context otherwise requires.

Below is a summary of ~~us, this section includes a~~the principal factors that make an investment in our common stock speculative or risky. This summary does not address all of the risks that we face. Additional discussion of ~~important factors~~the risks summarized in this risk factor summary, and other risks that ~~could affect~~we face, can be found below under the heading “Risk Factors” and should be carefully considered, together with other information in this Quarterly Report on Form 10-Q and our ~~business, operating results, financial condition~~other filings with the Securities and ~~the trading price of~~Exchange Commission, or SEC, before making investment decisions regarding our common stock. ~~This discussion should be read in conjunction with our condensed financial statements as of March 31, 2018 and December 31, 2017 and the notes accompanying those financial statements.~~

~~Risks Related to Our Limited Operating History, Financial Condition, and Capital Requirements~~

Risks Related to Our Limited Operating History, Financial Condition, and Capital Requirements

We are a ~~preclinical-stage~~clinical-stage biopharmaceutical company with a limited operating history and no products approved for commercial sale. We have incurred significant losses since our inception, and we anticipate that we will continue to incur losses for the foreseeable future, which, together with our limited operating history, make it difficult to assess our future viability.

We are a clinical-stage biopharmaceutical company with a limited operating history. Biopharmaceutical product development is a highly speculative undertaking and involves a substantial degree of risk. We have not yet sought approval for commercial sale of any products and therefore have no products approved for commercial sale and have not generated any product revenue ~~from contracts with customers~~ and have incurred losses in each year since our inception in March 2009. We have only a limited operating history upon which you can evaluate our business and prospects. In addition, we have limited experience and have not yet demonstrated an ability to successfully overcome many of the risks and

uncertainties frequently encountered by companies in new and rapidly evolving fields, particularly in the biopharmaceutical industry. We have only recently submitted our Investigational New Drug, or IND, application for one of our lead drug candidates, UBX0101, a senolytic small-molecule inhibitor of MDM2/p53, and have not initiated clinical studies for any of our drug candidates.

We have had significant operating losses since our inception. Our net loss for the three months ended ~~March 31, 2018,~~September 30, 2023 and ~~2017,~~2022 was approximately ~~$16.1~~$15.3 million and ~~$8.9~~$13.7 million, ~~respectively.~~respectively, and $38.4 million and $45.8 million, respectively, for the nine months ended September 30, 2023 and 2022. As of ~~March 31, 2018,~~September 30, 2023, we had an accumulated deficit of ~~$103.0~~$498.3 million. Substantially all of our losses have resulted from expenses incurred in connection with our research and development programs and from general and administrative costs associated with our operations. We expect to continue to incur losses for the foreseeable future, and we anticipate these losses will increase as we continue to develop our drug candidates, conduct clinical studies and pursue research and development activities. Even if we achieve profitability in the future, we may not be able to sustain profitability in subsequent periods. Our prior losses, combined with expected future losses, have had and will continue to have an adverse effect on our stockholders’ equity and working ~~capital.~~capital.

In recent fiscal periods our financial condition has raised substantial doubt as to our ability to continue as a going concern.

Based on our current operating plans and following the cash exercise by certain holders of existing warrants, we expect our existing capital resources will fund our planned operating expenses into the third quarter of 2025, which will be used to advance UBX1325 (foselutoclax). We expect to continue to incur net operating losses for at least the next several years as we continue our research and development efforts, advance our drug candidates through preclinical and clinical development, seek regulatory approval, prepare for and, if approved, proceed to commercialization. We do not expect to generate revenue from any drug candidates that we develop until we obtain regulatory approval for one or more of such drug candidates and commercialize our products or enter into collaborative agreements with third parties.

In recent fiscal periods, these conditions have raised substantial doubt about our ability to continue as a going concern. For example, our independent registered public accounting firm included in its audit opinion for the year ended December 31, 2022 an explanatory paragraph that there was substantial doubt as to our ability to continue as a going concern. The reaction of investors to the inclusion of a going concern statement by our auditors may materially adversely affect our share price and our ability to raise new capital or enter into partnerships. While our financial statements have been prepared assuming that we will continue to operate as a going concern, which contemplates the realization of assets and the satisfaction of liabilities in the normal course of business, we will need to raise additional funds. There is no assurance that funding will be available to us, will be obtained on terms favorable to us or will provide us with sufficient funds to meet our objectives. Failure to raise additional financing may adversely impact our ability to achieve our intended business objectives because without substantial additional capital, we may not be able to complete pivotal trials necessary to advance our product development and our programs. If we become unable to continue as a going concern, we may have to liquidate our assets and the values we receive for our assets in liquidation or dissolution could be significantly lower than the values reflected in our financial statements.

We will require substantial additional financing to achieve our goals, and a failure to obtain this capital when needed on acceptable terms, or at all, could force us to delay, limit, reduce or terminate our product development, other operations or commercialization efforts.

Since our inception, we have invested a significant portion of our efforts and financial resources in research and development activities. Preclinical studies and clinical studies for our drug candidates and additional research and development activities to discover and develop new drug candidates will require substantial funds to complete. As of ~~March 31, 2018,~~September 30, 2023, we had capital resources consisting of cash, cash equivalents, and marketable securities of ~~$134.6~~$45.9 million. In March and April 2018, we sold and issued an aggregate of 3,913,425 shares of our Series C convertible preferred stock at $15.3317 per share for net cash proceeds to us of approximately $59.9 million. In May 2018, we completed our initial public offering and received net proceeds of $76.1 million, after deducting underwriting discounts, commissions and offering expenses payable by us. We believe that we will continue to expend substantial resources for the foreseeable future in connection with our programs, including the ~~preclinical and~~ clinical development of ~~our lead drug candidates, UBX0101~~UBX1325, and ~~UBX1967, and~~ the ~~discovery and~~ development of any other drug candidates we may choose to pursue. These expenditures will include costs associated with conducting preclinical studies and clinical studies, obtaining regulatory approvals, and manufacturing and supply, as well as marketing and selling any products approved for sale. In addition, other unanticipated costs may arise. Because the outcome of any preclinical study or clinical study is highly uncertain, we cannot reasonably estimate the actual amounts necessary to successfully complete the development and commercialization of our ~~lead~~current drug candidates or any future drug candidates.

WeIn February 2022, and again on May 4, 2023, we announced a restructuring to align resources to focus on our ongoing clinical programs and deliver on key development milestones. These actions to prioritize our

ophthalmology programs, optimize resource allocation, extend our runway, and implement cost saving measures were designed to enable us to achieve multiple key clinical data readouts for UBX1325. As part of the May 2023 restructuring actions, we reduced our headcount by a total of nine employees, or approximately 29%, effective as of May 31, 2023, with three employees who departed as of June 30, 2023.

Based on our current operating plans and following the cash exercise by certain holders of existing warrants, we expect our existing capital resources ~~together with the proceeds from the sale of our Series C stock and IPO~~ will fund our planned operating expenses into ~~2021, based on our current plan. However, our operating plans may change as a result~~the third quarter of ~~many factors currently unknown~~2025, which will be used to ~~us, and we may~~advance UBX1325.

We will need to seek additional funds sooner than planned, through public or private equity or debt financings or other sources, such as strategic collaborations. Such financing may result in dilution to stockholders, imposition of burdensome debt covenants and repayment obligations, or other restrictions that may affect our business. In addition, we may seeksubstantial additional capital ~~due~~ to ~~favorable market conditions or strategic considerations even if~~operate our business and continue our development activities and without substantial additional capital, we ~~believe we have sufficient funds for our current or future operating plans.~~

~~Additional funds~~ may not be able to complete pivotal trials necessary to advance our product development and our programs. If funding is only available ~~when we need them,~~ on less desirable terms ~~that are acceptable to us,~~ or ~~at all. If adequate funds are~~ not available ~~to us on a timely basis, we may be required to:~~

We also could be required to seek funds through arrangements with collaborators or others that may require us to relinquish rights to some of our technologies or drug candidates that we would otherwise pursue on our own. We do not expect to realize revenue from sales of products or royalties from licensed productscompanies in the ~~foreseeable future,~~life sciences industry or if we are unable to access our cash deposits held at ~~all,~~financial institutions due any liquidity concerns at such financial institutions, our business and ~~unless and until our drug candidates are clinically tested, approved for commercialization and successfully marketed.~~ operations would be adversely affected.

To date, we have primarily financed our operations through the sale of ~~debt and~~ equity securities. For example, in March 2022, we filed a Registration Statement on Form S-3 covering the offering of up to $125.0 million of common stock, preferred stock, debt securities, warrants and units, which was declared effective by the SEC in May 2022, or the March 2022 Shelf Registration Statement. In March 2022, we also entered into a sales agreement, as amended in August 2022, or the March 2022 Sales Agreement, with Cowen and Company, LLC, or Cowen, as sales agent to sell shares of our common stock, from time to time, with aggregate gross sales proceeds of up to $25.0 million pursuant to the March 2022 Shelf Registration Statement as an “at-the-market” offering under the Securities Act, or the March 2022 ATM Offering Program. Further, in October 2022, we filed a Registration Statement on Form S-3 covering the offering of up to $250.0 million of common stock, preferred stock, debt securities, warrants and units, or the October 2022 Shelf Registration Statement and, together with the March 2022 Shelf Registration Statement, the shelf registration statements. In October 2022, we also entered into a sales agreement with Cowen as sales agent to sell shares of our common stock, from time to time, with aggregate gross sales proceeds of up to $50.0 million pursuant to the October 2022 Shelf Registration Statement as an “at-the-market” offering under the Securities Act, or the October 2022 ATM Offering Program, and, together with the March 2022 ATM Offering Program, the ATM Offering Programs.

We will be required to seek additional funding in the future and currently intend to do so through collaborations, public or private equity offerings or debt financings, credit or loan facilities or a combination of one or more of these funding sources. ~~Our ability~~Such financing may result in dilution to raise additional funds will depend on financial, economic and other factors, many of which are beyond our control. Additional funds may not be available to us on acceptable terms or at all. If we raise additional funds by issuing equity securities, our stockholders ~~will suffer dilution~~ and the terms of any financing may adversely affect the rights of our stockholders. In addition, as a condition to providing additional funds to us, future investors may demand, and may be granted, rights superior to those of existing stockholders. Debt financing, if available, is likely to involve restrictive covenants limiting our flexibility in conducting future business activities, and, in the event of insolvency, debt holders would be repaid before holders of our equity securities received any distribution of our corporate assets.

~~Due~~Our ability to raise additional funds will depend on financial, economic and other factors, many of which are beyond our control. For example, financial markets have been negatively impacted by current macroeconomic trends and the COVID-19 pandemic. The financial markets have further been negatively affected by high interest rates, rising inflation, the government closure of Silicon Valley Bank and liquidity concerns at other financial institutions, and the potential for local and/or global economic recession. Such impacts may be exacerbated by unforeseen events or public health emergencies. Adequate funding may not be available to us on acceptable terms, or at all, particularly in light of these conditions. In addition, we may seek additional capital due to favorable market conditions or strategic considerations even if we believe we have sufficient funds for our current or future operating plans.

We currently have shelf registration statements effective and existing ATM Offering Programs, however, our ability to raise capital under these registration statements and through these ATM Offering Programs may be limited by, among other things, SEC rules and regulations impacting the eligibility of smaller companies to use Form S-3 for primary offerings of securities. Based on our public float, as of the date of the filing of this Quarterly Report on Form 10-Q, we are only permitted to utilize a shelf registration statement, including the registration statements under which our ATM Offering Programs are operated, subject to Instruction I.B.6 to Form S-3, which is referred to as the “baby shelf” rule. For so long as our public float is less than $75.0 million, we may not sell more than the equivalent of one-third of our public float during any 12 consecutive months pursuant to the ~~significant resources required for~~ baby shelf rules. Although alternative public

and private transaction structures may be available, these may require additional time and cost, may impose operational restrictions on us, and may not be available on attractive terms.

Additional and sufficient funds may not be available when we need them, on terms that are acceptable to us, or at all. If adequate funds are not available to us on a timely basis, we may be required to:

We also could choose or be required to ~~treat age-associated diseases~~seek funds through arrangements with collaborators or others that may require us to relinquish rights to some of our technologies or drug candidates that we would otherwise pursue on our own. We do not expect to realize revenue from sales of products or royalties from licensed products in the foreseeable future, if at all, and ~~extend human healthspan. We are currently developing multiple senolytic molecules to address a variety of age-associated diseases, including musculoskeletal, ophthalmologic~~unless and pulmonary disorders. In addition, we are pursuing other aging mechanisms, such as loss of circulating youth factors and mitochondrial dysfunction, which also have the potential to reduce the damaging effects of age. We seek to maintain a process of prioritization and resource allocation among our programs to maintain a balance between aggressively advancing lead programs in identified indications and exploring additional indications or mechanisms to effect diseases of aging. However, due to the significant resources required for the development ofuntil our drug candidates are clinically tested, approved for commercialization and successfully marketed.

We may not be able to maintain compliance with the continued listing requirements of Nasdaq, and, if so, we ~~must focus~~would be subject to delisting.

Our common stock is currently listed for trading on ~~specific diseases~~the Nasdaq Global Select Market under the symbol “UBX”. The continued listing of our common stock on Nasdaq is subject to our compliance with a number of listing standards. On June 3, 2022, we received a letter from the Listing Qualifications Staff of The Nasdaq Stock Market LLC indicating that for the last 30 consecutive business days, the closing bid price of our common stock was below $1.00 per share, which is the minimum required closing bid price for continued listing on the Nasdaq Global Select Market pursuant to Listing Rule 5450(a)(1).We had 180 calendar days, or until November 30, 2022, to regain compliance. To regain compliance, the closing bid price of our common stock needed to be at least $1.00 per share for a minimum of ten consecutive business days. On October 19, 2022, we effected a 1-for-10 reverse stock split of our common stock seeking to regain compliance with Nasdaq Global Select Market's continued listing standards. From October 20, 2022 to November 2, 2022 (10 consecutive business days), the closing bid price of our common stock exceeded $1.00 per share. Accordingly, on November 3, 2022, we received a notice from Nasdaq indicating that we have regained compliance with Listing Rule 5450(a)(1) as of such date.

Although we currently comply with the minimum bid requirement following the reverse stock split, our bid price could fall below $1.00 per share again in the future, in which event we would receive another deficiency notice from Nasdaq advising us that we have 180 days to regain compliance by maintaining a minimum bid price of at least $1.00 for a minimum of ten consecutive business days. Under certain circumstances, Nasdaq could require that the minimum bid price exceed $1.00 for more than ten consecutive days before determining that a company complies. If we fail to satisfy the Nasdaq’s continued listing requirements, we may transfer to the OTC Bulletin Board. Having our common stock trade on the OTC Bulletin Board could adversely affect the liquidity of our common stock. Any such transfer could make it more difficult to dispose of, or obtain accurate quotations for the price of, our common stock, and ~~disease pathways and decide which drug candidates to pursue~~there also would likely be a reduction in our coverage by securities analysts and the ~~amount~~news media, which could cause the price of ~~resources~~our common stock to ~~allocate~~decline further and adversely impact the ability of stockholders to ~~each. Our near-term objective is~~sell our common stock. We may also face other material adverse consequences in such event such as negative publicity, a decreased ability to ~~demonstrate~~obtain additional financing, diminished investor and/or employee confidence, and the loss of business development opportunities, any of which may contribute to a further decline in our clinical studies that local treatment with senolytic molecules can alter the course of an age-associated disease. To accomplish this goal, we submitted our IND application in March 2018, and we expect to initiate a Phase 1 clinical study of UBX0101 in osteoarthritic patients in the second quarter of 2018. In addition, we plan to submit our IND application and commence a Phase 1 clinical study of UBX1967 in an ophthalmologic indication in the second half of 2019.stock price.

Our decisions concerning the allocation of research, development, collaboration, management and financial resources toward particular drug candidates or therapeutic areas may not lead to the development of any viable commercial product and may divert resources away from better opportunities. Similarly, our potential decisions to delay, terminate or collaborate with third parties in respect of certain programs may subsequently also prove to be suboptimal and could cause us to miss valuable opportunities. If we make incorrect determinations regarding the viability or market potential of any of our programs or drug candidates or misread trends in the aging or healthspan or biopharmaceutical industry, our business, financial condition and results of operations could be materially adversely affected. As a result, we may fail to capitalize on viable commercial products or profitable market opportunities, be required to forego or delay pursuit of opportunities with other drug candidates or other diseases and disease pathways that may later prove to have greater commercial potential than those we choose to pursue, or relinquish valuable rights to such drug candidates through collaboration, licensing or other royalty arrangements in cases in which it would have been advantageous for us to invest additional resources to retain development and commercialization rights.

Our operating results may fluctuate significantly, which makes our future operating results difficult to predict and could cause our operating results to fall below expectations.

Our quarterly and annual operating results may fluctuate significantly, ~~which makes~~making it difficult for us to predict our future operating results. These fluctuations may occur due to a variety of factors, many of which are outside of our control and may be difficult to predict, including:

The cumulative effects of these factors could result in large fluctuations and unpredictability in our quarterly and annual operating results. As a result, comparing our operating results on a period-to-period basis may not be meaningful. Investors should not rely on our past results as an indication of our future performance.

This variability and unpredictability could also result in our failing to meet the expectations of industry or financial analysts or investors for any period. If our revenue or operating results fall below the expectations of analysts or investors or below any forecasts we may provide to the market, or if the forecasts we provide to the market are below the expectations of analysts or investors, the price of our common stock could decline substantially. Such a stock price decline could occur even when we have met any previously publicly stated revenue or earnings guidance we may provide.

Our core therapeutic approach to ~~extending human healthspan~~slow, halt, or reverse diseases of aging is based on our understanding of cellular senescence. Utilizing senolytic molecules to treat ~~age-associated~~ diseases of aging is a novel therapeutic approach, which exposes us to unforeseen risks and makes it difficult to predict the time and cost of drug development and potential for regulatory approval.

~~We are developing a pipeline of drug candidates to treat age-associated diseases and extend human healthspan.~~ Our foundational science and lead drug ~~candidates~~candidate are based on ~~senescent~~senescence biology. We believe that we can develop drug candidates capable of eliminating or modulating accumulated senescent cells, ~~and the associated Senescence Associated Secretory Phenotype, or SASP,~~ when administered ~~locally, and eventually develop systemic~~locally. In our development efforts we intend to explore senolytic medicines ~~using~~that use multiple modalities. However, ~~this~~our approach to treating ~~age-associated~~ diseases of aging is novel and the scientific research that forms the basis of our efforts to develop senolytic medicines is ongoing. We ~~currently~~ have only recently begun testing our senolytic molecules in humans and the majority of our current data supporting our hypothesis regarding senescence biology is limited ~~data,~~to pre-clinical animal models and in vitro cell lines, the results of which may not translate into humans. We currently have no conclusive evidence in humans, that the accumulation or modulation of senescent cells ~~and resulting exposure to SASP factors~~ is the underlying cause of tissue damage and dysfunction associated with many ~~age-associated diseases. Further,~~diseases of aging. For example, in August 2020, we announced the 12-week results from our Phase 2 study of UBX0101 in patients with moderate-to-severe painful OA of the knee. There was no statistically significant difference between any arm of UBX0101 and placebo at the 12-week primary endpoint for change from baseline in WOMAC-A, an established measurement of pain in OA. Given these results, we decided not to progress UBX0101 into pivotal studies and have ~~not yet tested~~narrowed our ~~senolytic molecules in humans~~near-term focus mainly to our ongoing ophthalmologic disease programs.

Our current program, UBX1325 (foselutoclax), is a Bcl-xL inhibitor, and ~~our current data~~ is ~~limited~~intended to animal models and preclinical cell lines, the results of which may not translate into humans. As such, there can be no assurances that even if we are able to develop senolytic medicines capable of eliminatingtarget senescent cells ~~that such medicines would safely and effectively treat age-associated diseases.~~

in the eye. While cellular senescence is a ~~natural~~naturally occurring biological process, the administration of senolytic medicines to eliminate or cause the elimination or modulation of accumulated senescent cells in humans ~~is untested~~has not been widely tested and may potentially harm healthy tissue or result in unforeseen safety ~~events.~~events, or fail to achieve the intended therapeutic purpose entirely. We may also ultimately discover that our senolytic molecules do not possess certain properties required for therapeutic effectiveness, or that even if found to be effective in one type of tissue, that such molecules ~~are not~~will be effective in other tissues. In addition, given the novel nature of this therapeutic approach, designing preclinical and clinical studies to demonstrate the effect of senolytic medicines is complex and exposes us to unforeseen risks. For example, attempts to replicate mouse anterior cruciate ligament, or ACL, transection findings using different animal models of osteoarthritis, or OA, have proven to be challenging, as it is difficult to mimic a disease like OA, which develops over a long period of time in humans, in short-term animal models. A model of OA using the rat medial meniscal-tibial ligament, or MX, transection failed to produce significant senescence, while a recently conducted canine model of OA in which both the ACL and MX were transected produced significantly higher levels of senescence (roughly 10-fold higher than that of the mouse ACL model). In ~~those studies, administration of UBX0101 did not appear to affect either senescence burden or SASP factors. Further,~~addition, the scientific evidence to support the feasibility of developing systemic senolytic medicines is ~~both preliminary~~based primarily on preclinical data and ~~limited.~~not human clinical trials. We may spend substantial funds attempting to develop these drug candidates and never succeed in doing so.

No regulatory authority has granted approval for a senolytic medicine. As such, we believe the U.S. Food and Drug Administration, or the FDA, has limited experience with ~~biological~~ senescence, which may increase the complexity, uncertainty and length of the clinical development and regulatory approval process for our drug candidates. We may never receive approval to market and commercialize any drug candidate. Even if we obtain regulatory approval, the approval may be for targets, disease indications or patient populations that are not as broad as we intended or desired or may require labeling that includes significant use or distribution restrictions or safety warnings. We may be required to perform additional or unanticipated clinical studies to obtain approval or be subject to post-marketing testing requirements to maintain ~~regulatory approval.~~marketing authorization. If our other senolytic molecules prove to be ineffective, unsafe or

commercially unviable, our entire senolytic platform and pipeline would have little, if any, value, which would have a material and adverse effect on our business, financial condition, results of operations and prospects.

Our business is currently dependent on the successful development ~~regulatory approval, and commercialization~~ of ~~our drug candidates, all of~~UBX1325, which ~~are~~is in early stages of ~~development and none of which have been tested in a human subject.~~clinical development.

We have no products approved for sale and all of our drug candidates are in early stages of development. ~~Our lead drug~~We have one product candidate, ~~UBX0101, has not yet been evaluated~~UBX1325, in clinical development and are focused on advancing our ophthalmology program. In particular, in October 2020, we initiated a Phase 1 clinical study of UBX1325 in patients with DME or nAMD for whom anti-VEGF therapy was no longer considered beneficial, and in July, October, and November 2021, we announced positive data up to 24 weeks from this Phase 1 study. We initiated a Phase 2 proof-of-concept clinical study of UBX1325 in DME (BEHOLD) in May 2021, dosed the first patient in June 2021 and announced positive 24-week safety and efficacy data in November 2022, and announced positive 48-week safety and efficacy data in April 2023. In April 2022 we also dosed our ~~other lead drug candidate, UBX1967, has yet~~first patient in our Phase 2 proof-of-concept study in nAMD (ENVISION), and we shared 16- and 24-week data in March 2023, and 48-week data in September 2023. We have also begun a head-to-head Phase 2b (ASPIRE) study to ~~complete IND-enabling studies. Further,~~explore the efficacy of UBX1325 in patients with DME compared to the current standard of care, aflibercept.

In February 2022, and again on May 4, 2023, we ~~have not yet administered any of~~announced a restructuring to align resources to focus on our ~~drug candidates in humans~~ongoing clinical programs and ~~as such, we face significant translational risk with~~deliver on key development milestones. These actions to prioritize our ~~drug candidates. The success of~~ophthalmology programs, optimize resource allocation, extend our runway, and implement cost saving measures were designed to enable us to achieve multiple key clinical data readouts for UBX1325. As a result, our business, including our ability to finance our company and generate any revenue in the future, ~~will primarily depend~~is currently dependent on the successful development ~~regulatory approval~~of UBX1325. If UBX1325 does not demonstrate clinical benefit, we may be required to significantly delay or abandon its development. In the event UBX1325 is not successful in clinical development, we have limited resources and ~~commercialization of~~capital with which to develop additional drug candidates ~~from our senolytic medicine pipeline. However, given our early stage of development, it~~and we may be ~~many years, if we succeed at all, before we have demonstrated the safety and efficacy of a drug candidate sufficient~~forced to ~~warrant approval for commercialization.~~

~~In the future, we may also become dependent on other drug candidates that we may develop~~sell or ~~acquire.~~ liquidate our business.

The clinical and commercial success of ~~our drug candidates~~UBX1325, and any other future drug candidates, will depend on a number of factors, including the following:

These factors, many of which are beyond our control, could cause us to experience significant delays or ~~an inability~~be unable to obtain regulatory approvals or commercialize our drug candidates. In addition, disruptions caused by the COVID-19 pandemic in the last few years may increase the likelihood that we encounter such difficulties or delays in developing, obtaining regulatory approvals for or commercializing our product candidates. Even if regulatory approvals are obtained, we may never ~~be able to successfully commercialize~~achieve success in commercializing any of our drug candidates. Accordingly, we cannot provide assurances that we will be able to generate sufficient revenue through the sale of our drug candidates or any future drug candidates to continue our business or achieve profitability.

~~We may be unable to obtain regulatory approval for our drug candidates under applicable regulatory requirements. The denial or delay of any such approval would delay commercialization~~Other than UBX1325, all of our other programs are preclinical and face significant development risk.

Other than UBX1325, all of our other programs are in preclinical and early research stage. In addition, we have limited resources for which to develop any products other than UBX1325. Given the early stage nature of these programs, each of the drug candidates and ~~adversely impact our potential to generate revenue, our business and our results of operations.~~

~~To gain approval to market our drug candidates, we must provide~~programs faces substantial development risk. UBX1325 is the ~~FDA and foreign regulatory authorities with clinical data that adequately demonstrate the safety and efficacy of the~~only current drug candidate ~~for the intended indication applied for in the applicable regulatory filing. For~~that we have administered to humans, and as such, we face significant translational risk with our ~~senolytic medicines, we must~~earlier stage drug candidates. We may also demonstrate that eliminating senescent cells and the associated SASP will lead to the improvement of well-defined and measurable endpoints. Product development is a long, expensive and uncertain processes, and delay or failure can occur at any stage of any of our clinical development programs. A number of companies in the biotechnology and pharmaceutical industries have suffered significant setbacks in clinical studies, even after promising results in earlier preclinical or clinical studies. These setbacks have been causedbe required by among other things, preclinical findings made while clinical studies were underway and safety or efficacy observations made in clinical studies, including previously unreported adverse events. Success in preclinical testing and early clinical studies does not ensure that later clinical studies will be successful, and the results of clinical studies by other parties may not be indicative of the results in trials we may conduct.

~~We have not previously submitted a new drug application, or NDA, or biologics license application, or BLA, to~~ the FDA or similar approval filings to comparable foreign regulatory authorities. An NDA, BLA or other relevant regulatory filing must include extensive preclinical and clinical data and supporting information to establish that the drug candidate is safe, pure and potent for each desired indication. The NDA, BLA or other relevant regulatory filing must also include significant information regarding the chemistry, manufacturing and controls for the product.

We submitted our IND application for UBX0101 in March 2018, and we plan to conduct IND-enabling studies of UBX1967. The research, testing, manufacturing, labeling, approval, sale, marketing and distribution of drug and biologic products are subject to extensive regulation by the FDA and other regulatory authorities in the United States and other countries, and such regulations differ from country to country. We are not permitted to market our drug candidates in the United States or in any foreign countries until they receive the requisite approval from the applicable regulatory authorities of such jurisdictions.

~~The FDA or any foreign regulatory bodies can delay, limit or deny approval of our drug candidates for many reasons, including:~~

~~Of the large number of biopharmaceutical and pharmaceutical products in development, only a small percentage successfully complete the FDA or other regulatory approval processes and~~trials. Accordingly, there can be no assurance that we are ~~commercialized.~~

~~Even if we eventually complete clinical testing and receive approval from the FDA or applicable foreign agencies for~~able to bring any of our ~~drug~~preclinical product candidates or development programs into the ~~FDA~~clinic or the applicable foreign regulatory agency may grant approval contingent on the performance of costly additional clinical studies which may be required after approval. The FDA or the applicable foreign regulatory agency also may approve our lead drug candidates for a more limited indication or a narrower patient population than we originally requested, and the FDA, or applicable foreign regulatory agency, may not approve our drug candidates with the labeling that we believe is necessary or desirable for the successful commercialization of such drug candidates.otherwise successfully develop them.

Any delay in obtaining, or inability to obtain, applicable regulatory approval would delay or prevent commercialization of our drug candidates and would materially adversely impact our business and prospects.

Clinical development involves a lengthy and expensive process with an uncertain outcome, and results of earlier studies and trials may not be predictive of future trial results.

Clinical testing is expensive and can take many years to complete, and its outcome is inherently uncertain. Failure or delay can occur at any time during the clinical study process. Success in preclinical studies and early clinical studies does not ensure that later clinical studies will be successful. A number of companies in the biotechnology, and pharmaceutical industries have suffered significant setbacks in clinical studies, even after positive results in earlier preclinical studies or clinical studies. These setbacks have been caused by, among other things, preclinical findings made while clinical studies were underway and safety or efficacy observations made in clinical studies, including previously unreported adverse events. The results of our preclinical animal studies or studies in ex vivo human tissues may not be predictive of the results of outcomes in human clinical studies. For example, our senolytic molecules may demonstrate different chemical and pharmacological properties in patients than they do in laboratory studies or may interact with human biological systems in unforeseen or harmful ways.

Drug candidates in later stages of clinical studies may fail to show the desired pharmacological properties or safety and efficacy traits despite having progressed through preclinical studies and initial clinical studies.

Notwithstanding any promising results in earlier studies, we cannot be certain that we will not face similar setbacks. Even if we are able to initiate and complete clinical studies, the results may not be sufficient to obtain regulatory approval for our drug candidates.

Although we submitted our IND application for UBX0101 in March 2018, and we expect to initiate a Phase 1 clinical study in the first half of 2018, we may experience delays in obtaining the FDA’s authorization to initiate clinical studies under such IND, completing ongoing studies of our other drug candidates and initiating our planned studies and trials. Additionally, weWe cannot be certain that studies or trials for our drug candidates will begin on time, not require redesign, enroll an adequate number of subjects on time or be completed on schedule, if at all. The COVID-19 pandemic or future pandemics or public health emergencies could cause or exacerbate these factors. For example, for our Phase 2 studies for UBX1325 and future studies, clinical sites may be unable to recruit and retain investigators and study staff, screen and enroll patients, patients may be unable to adhere to the study visit schedule, and the completion of the study could be delayed. Clinical studies can be prolonged, delayed or terminated for a variety of reasons, ~~including delays or failures related to:~~including:

We may experience numerous adverse or unforeseen events during, or as a result of, preclinical studies and clinical studies that could delay or prevent our ability to receive marketing approval or commercialize our drug candidates, including:

If we are required to conduct additional clinical studies or other testing of our drug candidates beyond those that we currently contemplate, if we are unable to successfully complete clinical studies of our drug candidates or other testing, if the results of these trials or tests are not positive or are only moderately positive, or if there are safety concerns, we may:

We could also encounter delays if a clinical study is suspended or terminated by us, by the IRBs of the institutions in which such trials are being conducted, by the Data Safety Monitoring Board, or DSMB, for such trial or by the FDA or other regulatory authorities. Such authorities may suspend or terminate a clinical study due to a number of factors, including failure to conduct the clinical study in accordance with regulatory requirements or our clinical protocols, inspection of the clinical study operations or trial site by the FDA or other regulatory authorities resulting in the imposition of a clinical hold, unforeseen safety issues or adverse side effects, failure to demonstrate a benefit from using a drug, changes in governmental regulations or administrative actions or lack of adequate funding to continue the clinical study.

Further, conducting clinical studies in foreign countries, as we may do for certain of our drug candidates, presents additional risks that may delay completion of our clinical studies. These risks include the failure of enrolled patients in foreign countries to adhere to clinical protocol as a result of differences in healthcare services or cultural customs, managing additional administrative burdens associated with foreign regulatory schemes, as well as political and economic risks relevant to such foreign ~~countries.~~countries, including those caused by unforeseen events such as pandemics and public health emergencies similar to the COVID-19 pandemic.

Principal investigators for our clinical studies may serve as scientific advisors or consultants to us from time to time and may receive cash or equity compensation in connection with such services. If these relationships and any related compensation result in perceived or actual conflicts of interest, or a regulatory authority concludes that the financial relationship may have affected the interpretation of the trial, the integrity of the data generated at the applicable

clinical study site may be questioned and the utility of the clinical study itself may be jeopardized, which could result in the delay or rejection of the marketing application we submit. Any such delay or rejection could prevent or delay us from commercializing our current or future drug candidates.

If we experience termination or delays in the completion ~~or termination,~~ of any preclinical study or clinical study of our drug candidates, the commercial prospects of our drug candidates may be harmed, and our ability to generate revenues from any of these drug candidates will be delayed or ~~not realized at all.~~unrealized. In addition, any delays in completing our clinical studies may increase our costs, slow down our drug candidate development and approval process and jeopardize our ability to commence product sales and generate revenues. Any of these occurrences may significantly harm our business, financial condition and prospects. In addition, many of the factors that cause, or lead to, a delay in the commencement or completion of clinical studies may also ultimately lead to the denial of regulatory approval of our drug candidates. If one or more of our drug candidates or our senescence technology generally prove to be ineffective, unsafe or commercially unviable, our ~~entire~~ platform and pipeline would have ~~little, if any,~~significantly diminished value, which would have a material and adverse effect on our business, financial condition, results of operations and prospects.

Public health emergencies such as the COVID-19 pandemic could adversely impact our ~~efforts to~~business, including our clinical trials, and financial condition.

Although the effects continue to ~~create~~diminish, the COVID-19 pandemic and government measures taken in response have had a ~~pipeline~~significant impact, both direct and indirect, on businesses and commerce, as worker shortages have occurred, supply chains have been disrupted, facilities and production have been suspended, and demand for certain goods and services, such as medical services and supplies, has spiked, while demand for other goods and services, such as travel, has fallen. In response to the spread of ~~drug candidates or to develop commercially successful products. If~~COVID-19, we ~~fail to successfully identify~~have adjusted our remote and ~~develop additional drug candidates,~~in-person working model based on applicable safety guidelines and the best interest of our ~~commercial opportunity~~employees, and may be ~~limited.~~required to take additional or different actions that could impact our operations if required by applicable laws or regulations or if we determine them to be in the best interest of our employees.

~~We are committed~~For the Phase 1 safety and tolerability clinical study and the Phase 2 proof-of-concept clinical studies for UBX1325, we adapted the clinical study protocol and standard operating procedures to developing senolytic medicines that slow, halt or reverse age-associated diseases and are currently advancing multiple senolytic molecules to address a variety of age-associated diseases, including musculoskeletal, ophthalmologic and pulmonary disorders. As senolytic medicines are not limited to intervention by a single mode of action or molecular target, we believe that we can modulateenable a number of ~~biologic pathways~~adaptations such as: remote data collection for clinical sites if needed; the option for remote data source verification procedures to limit on-site monitoring; transportation options for patients to utilize for study visit adherence; flexible visit windows to increase study visit adherence; and geographic distribution of sites to mitigate variation in ~~order~~local restrictions.

These actions enable the collection of all major endpoints if patients adhere with the study visit schedule. Assessments that require an on-site visit may be missed for some or all patients including laboratory evaluations, clinical examinations, or imaging.

CROs based in the United States that provide preclinical services are experiencing heavy demand, which may impact their ability to ~~trigger~~start new studies and could lead to delays in the ~~beneficial elimination~~commencement of ~~senescent cells. However,~~ our ~~core therapeutic approach is based~~preclinical studies. Several of our U.S.-based academic research partners have also experienced shutdowns which has slowed progress on several early-stage projects, none of which impacted our ~~belief that~~preclinical timelines.

As the ~~elimination~~remaining effects of the ~~accumulation~~COVID-19 pandemic continue, we may experience disruptions that could severely impact our business and clinical trials, including:

Lingering effects of the global pandemic of the COVID-19 coronavirus continue to evolve. The extent to which the COVID-19 pandemic may impact our business, including our clinical trials, and financial condition will depend on future developments, which are highly uncertain and cannot be predicted with confidence, such as the ultimate geographic spread of the disease, the duration of the pandemic, the adoption and efficacy of vaccines, travel restrictions and social distancing in the United States and other countries, business closures or business disruptions and the effectiveness of actions taken in the United States and other countries to contain and treat the root cause of many of the diseases of aging, which may never be successfully validated in a human. In addition, identifying, developing, obtaining regulatory approval and commercializing drug candidates for the treatment of age-associated diseases will require substantial additional funding beyond the net proceeds of the offering and is prone to the risks of failure inherent in drug development. Research programs to identify drug candidates also require substantial technical, financial and human resources, regardless of whether or not any drug candidates are ultimately identified, and even if our research programs initially show promise in identifying potential drug candidates, they may fail to yield drug candidates for clinical development.disease.

In addition, we believe that many age-associated diseases will require the development of systemic senolytic medicines and that the full potential to extend human healthspan will require additional non-senescence based therapeutic approaches. As a result, we intend to continue to dedicate significant resources and effort to better understand fundamental aging mechanisms, such as loss of circulating youth factors and mitochondrial dysfunction, and translate these insights into human medicines. However, the scientific evidence to support the feasibility of developing systemic senolytic medicines is both preliminary and limited and our non-senolytic programs are based on emerging science. We therefore cannot provide any assurance that we will be able to successfully identify or acquire additional drug candidates, advance any of these additional drug candidates through the development process, successfully commercialize any such additional drug candidates, if approved, or assemble sufficient resources to identify, acquire, develop or, if approved, commercialize additional drug candidates. If we are unable to successfully identify, acquire, develop and commercialize additional drug candidates, our commercial opportunity may be limited.

~~It may be many years, if ever, before we develop senolytic medicines capable of systemic administration to treat systemic diseases of aging.~~

We are focusing initially on the development of senolytic molecules for age-associated diseases that can be treated by means of local treatment and intend to continue our research into the development of systemic senolytic medicines. However, we are still at a very early stage of developing locally administered senolytic medicines, and we must establish proof-of-concept in humans for local treatment before developing a systemically administered senolytic medicine. We still face significant risks in the development of localized treatments. As a result, it may be many years before we have sufficient human data and scientific understanding to effectively pursue a systemically administered senolytic medicine, if ever.

If we encounter difficulties enrolling patients in our clinical studies, our clinical development activities could be delayed or otherwise adversely affected.

The timely completion of clinical studies in accordance with their protocols depends, among other things, on our ability to enroll a sufficient number of patients who remain in the study until its conclusion. We may experience difficulties in patient enrollment in our clinical studies for a variety of reasons. The enrollment of patients depends on many factors, including:

In addition, our clinical studies may compete with other clinical studies for drug candidates that are in the same therapeutic areas as our drug ~~candidates, and this~~candidates. This competition will reduce the number and types of patients available to us, because some patients who might have opted to enroll in our trials may instead opt to enroll in a trial being conducted by one of our competitors. Since the number of qualified clinical investigators is limited, we may conduct some of our clinical studies at the same clinical study sites that some of our competitors use, which will reduce the number of patients who are available for our clinical studies in such clinical study site.

Further, the administration of senolytic medicines designed to eliminate or cause the elimination of senescent cells and thereby modulate their associated SASP may result in unforeseen events, including by harming healthy tissues. As a result, it is possible that safety concerns could negatively affect patient enrollment among the patient populations that we intend to treat, including among those in indications with a low risk of mortality. Delays in patient enrollment may result in increased costs or may affect the timing or outcome of the planned clinical studies, which could prevent completion of these trials and adversely affect our ability to advance the development of our drug candidates.

Interim, “top-line” and preliminary data from our clinical trials that we announce or publish from time to time may change as more patient data become available and are subject to audit and verification procedures that could result in material changes in the final data.

From time to time, we may publicly disclose top-line or preliminary data from our clinical trials, which is based on a preliminary analysis of then-available data, and the results and related findings and conclusions are subject

to change following a more comprehensive review of the data related to the particular study or trial. We also make assumptions, estimations, calculations and conclusions as part of our analyses of data, and we may not have received or had the opportunity to fully and carefully evaluate all data. As a result, the top-line or preliminary results that we report may differ from future results of the same studies, or different conclusions or considerations may qualify such results, once additional data have been received and fully evaluated. Top-line or preliminary data also remain subject to audit and verification procedures that may result in the final data being materially different from the top-line or preliminary data we previously published. As a result, top-line and preliminary data should be viewed with caution until the final data are available.

From time to time, we may also disclose interim data from our preclinical studies and clinical trials. Interim data from clinical trials that we may conduct are subject to the risk that one or more of the clinical outcomes may materially change as patient enrollment continues and more patient data become available. Adverse differences between interim data and final data could significantly harm our business prospects. Further, disclosure of interim data by us or by our competitors could result in volatility in the price of our common stock.

Further, others, including regulatory agencies, may not accept or agree with our assumptions, estimates, calculations, conclusions or analyses or may interpret or weigh the importance of data differently, which could impact the value of the particular program, the approvability or commercialization of the particular product candidate or product, our ability to make certain claims about our products, and our company in general. In addition, the information we choose to publicly disclose regarding a particular study or clinical trial is based on what is typically extensive information, and you or others may not agree with what we determine is material or otherwise appropriate information to include in our disclosure.

If the interim, top-line or preliminary data that we report differ from actual results, or if others, including regulatory authorities, disagree with the conclusions reached, our ability to obtain approval for, and commercialize, our product candidates may be harmed, which could harm our business, operating results, prospects or financial condition.

Disruptions at the FDA and other government agencies caused by funding shortages or global health concerns could hinder their ability to hire, retain, or deploy key leadership and other personnel, or otherwise prevent products from being developed, approved, or commercialized in a timely manner or at all, which may adversely affect our business.

The ability of the FDA and other government agencies to review and approve new products can be affected by a variety of factors, including government budget and funding levels, ability to hire and retain key personnel and accept the payment of user fees, and statutory, regulatory, and policy changes. In addition, government funding of other government agencies that fund research and development activities is subject to the political process, which is inherently fluid and unpredictable. Disruptions at the FDA and other agencies, including a prolonged government shutdown, may cause significant regulatory delays and, therefore, delay our efforts to seek approvals and adversely affect our business, financial condition, results of operations, or cash flows. For example, over the last several years, the U.S. government has shut down several times, and certain regulatory agencies, such as the FDA, have had to furlough critical employees and stop critical activities.

Separately, in response to the global COVID-19 pandemic, the FDA postponed most inspections of domestic and foreign manufacturing facilities at various points. Even though the FDA has since resumed standard inspection operations where feasible, the FDA has continued to monitor and implement changes to its inspectional activities to ensure the safety of its employees and those of the firms it regulates as it adapts to the lingering effects of the COVID-19 pandemic, and any resurgence of the virus or emergence of new variants may lead to further inspectional delays. Regulatory authorities outside the United States may adopt similar restrictions or other policy measures in response to the COVID-19 pandemic. If a prolonged government shutdown occurs, or if global health concerns continue to prevent the FDA and other regulatory authorities from conducting their regular inspections, reviews, or other

regulatory activities, it could significantly impact the ability of the FDA and other regulatory authorities to timely review and process our regulatory submissions, which could have a material adverse effect on our business.

Our drug candidates may cause undesirable side effects or have other properties that could delay or prevent their regulatory approval, limit the commercial profile of an approved label, or result in significant negative consequences following marketing approval, if any.

Undesirable side effects caused by our drug candidates could cause us or regulatory authorities to interrupt, delay or halt clinical studies and could result in a more restrictive label or the delay or denial of regulatory approval by the FDA or comparable foreign regulatory authorities. NoOther than our clinical studies of UBX0101 and UBX1325 (foselutoclax), senolytic medicines designed to eliminate or cause the elimination of senescent cells ~~and~~

~~associated SASP~~ have ~~ever~~never been tested in humans. As a result, ~~any~~although UBX1325 has been well tolerated in our Phase 1 and Phase 2 clinical studies ~~we initiate~~with no adversities that would prevent advancement into later stage clinical trials as of the date of this Quarterly Report on Form 10-Q, UBX1325 could reveal a high and unacceptable severity and prevalence of side effects, and it is possible that patients enrolled in such clinical studies could respond in unexpected ways. For instance, in preclinical in vivo animal and ex vivo human tissue studies, our senolytic molecules have exhibited clearance of senescent ~~cells,~~cells; however, the elimination of accumulated senescent cells may result in unforeseen events, including by harming healthy cells or tissues. In addition, the entry by cells into a senescent state is a natural biological process that we believe may have protective effects, such as halting the proliferation of damaged cells. The treatment of tissues with senolytic molecules could interfere with such protective processes.

If unacceptable side effects arise in the development of our drug candidates, we, the FDA, the IRBs at the institutions in which our studies are conducted, or the DSMB could suspend or terminate our clinical studies, or the FDA or comparable foreign regulatory authorities could order us to cease clinical studies or deny approval of our drug candidates for any or all targeted indications. Treatment-related side effects could also affect patient recruitment or the ability of enrolled patients to complete any of our clinical studies or result in potential product liability claims. In addition, these side effects may not be appropriately recognized or managed by the treating medical staff. We expect to have to train medical personnel using our drug candidates to understand the side effect profiles for our clinical studies and upon any commercialization of any of our drug candidates. Inadequate training in recognizing or managing the potential side effects of our drug candidates could result in patient injury or death. Any of these occurrences may harm our business, financial condition and prospects significantly.

In addition, even if we successfully advance any of our drug candidates into and through clinical studies, such trials will likely only include a limited number of subjects and limited duration of exposure to our drug candidates. As a result, we cannot be assured that adverse effects of our drug candidates will not be uncovered when a significantly larger number of patients are exposed to the drug candidate. Further, ~~any~~ clinical studies may not be sufficient to determine the effect and safety consequences of taking our drug candidates over a multi-year period. There can be no assurance that it will demonstrate a similarly favorable safety profile in subsequent clinical trials.

If any of our drug candidates receives marketing approval, and we or others later identify undesirable side effects caused by such products, a number of potentially significant negative consequences could result, including:

Any of the foregoing events could prevent us from achieving or maintaining market acceptance of the particular drug candidate, if approved, and result in the loss of significant revenues to us, which would materially and adversely affect our results of operations and business. In addition, if one or more of our drug candidates or our senescence approach generally prove to be unsafe, our entire platform and pipeline could be affected, which would have a material and adverse effect on our business, financial condition, results of operations and prospects.

We may not be successful in our efforts to continue to create a pipeline of drug candidates or to develop commercially successful products. If we fail to successfully identify and develop additional drug candidates, our commercial opportunity may be limited.

We are committed to developing senolytic medicines that slow, halt, or reverse diseases of aging, and we are currently advancing multiple senolytic molecules to address a variety of diseases of aging, including ophthalmologic disorders. As senolytic medicines are not limited to intervention by a single mode of action or molecular target, we believe that we can modulate a number of biologic pathways in order to trigger the beneficial elimination of senescent cells. However, our core therapeutic approach is based on our belief that senescent cells drive diseases of aging, and that hypothesis has not yet been proven. In addition, we do not know if we will be able to develop medicines that selectively eliminate senescent cells or whether the elimination of such senescent cells will mitigate the effects of or effectively treat any diseases.

In addition, identifying, developing, obtaining regulatory approval and commercializing drug candidates for the treatment of diseases of aging will require substantial additional funding and is prone to the risks of failure inherent in drug development. Research programs to identify drug candidates also require substantial technical, financial and human resources, regardless of whether or not any drug candidates are ultimately identified, and even if our preclinical research programs initially show promise in identifying potential drug candidates, they may fail to yield drug candidates for clinical development.

While we have a number of ongoing drug discovery programs targeting senescent cells, we do not know whether these will be successful, or whether we will be able to identify novel senolytic mechanisms to continue to build our pipeline. We also cannot provide any assurance that we will be able to successfully identify or acquire additional drug candidates, advance any of these additional drug candidates through the development process, successfully commercialize any such additional drug candidates, if approved, or assemble sufficient resources to identify, acquire, develop or, if approved, commercialize additional drug candidates. If we are unable to successfully identify, acquire, develop and commercialize additional drug candidates, our commercial opportunities may be limited.

We may be unable to obtain regulatory approval for our drug candidates under applicable regulatory requirements. The denial or delay of any such approval would delay commercialization of our drug candidates and adversely impact our potential to generate revenue, our business and our results of operations.

To gain approval to market our drug candidates, we must provide the FDA and foreign regulatory authorities with clinical data that adequately demonstrate the safety and efficacy of the drug candidate for the intended indication applied for in the applicable regulatory filing. For our senolytic medicines, we must also demonstrate that eliminating or causing the elimination of senescent cells and modulating relevant associated SASP factors will lead to the improvement of well-defined and measurable endpoints.

We have not previously submitted a new drug application, or NDA, or biologics license application, or BLA, to the FDA, or similar approval filings to comparable foreign regulatory authorities. An NDA, BLA or other relevant regulatory filing must include extensive preclinical and clinical data and supporting information to establish that the drug candidate is safe and effective, or that a biological drug candidate is safe, pure and potent for each desired indication. The NDA, BLA or other relevant regulatory submission must also include significant information regarding the chemistry, manufacturing and controls for the product.

The research, testing, manufacturing, labeling, approval, sale, marketing, and distribution of drug and biologic products are subject to extensive regulation by the FDA and other regulatory authorities in the United States and other countries, and such regulations differ from country to country. We are not permitted to market our drug candidates in the United States or in any foreign countries until they receive the requisite approval from the applicable regulatory authorities of such jurisdictions.

The FDA or any foreign regulatory bodies can delay, limit or deny approval of our drug candidates for many reasons, including:

Of the large number of biopharmaceutical and pharmaceutical products in development, only a small percentage successfully complete the FDA or other regulatory approval processes and are commercialized.

Even if we eventually complete clinical testing and receive approval from the FDA or applicable foreign agencies for any of our drug candidates, the FDA or the applicable foreign regulatory agency may grant approval contingent on the performance of costly additional clinical studies which may be required after approval. The FDA or the applicable foreign regulatory agency also may approve our current drug candidates for limited indications or narrower patient populations than we originally requested, and the FDA, or applicable foreign regulatory agency, may not approve our drug candidates with the labeling that we believe is necessary or desirable for the successful commercialization of such drug candidates.

Even if our ~~lead~~current drug candidates or any future drug candidates obtain regulatory approval, they may fail to achieve the broad degree of physician and patient adoption and use necessary for commercial success.

Even if one or more of our drug candidates receive FDA or other regulatory approvals, the commercial success of any of our current or future drug candidates will depend significantly on the broad adoption and use of the resulting product by physicians and patients for approved indications. Our drug candidates may not be commercially ~~successful. For~~successful for a variety of reasons, ~~including among other things,~~including: competitive factors, pricing or physician preference, reimbursement by insurers, and the degree and rate of physician and patient adoption of our current or future drug candidates. If approved, the commercial success of our drug candidates ~~if approved,~~ will depend on a number of factors, including:

We cannot assure you that our current or future drug candidates, if approved, will achieve broad market acceptance among physicians and patients. Any failure by our drug candidates that obtain regulatory approval to achieve market acceptance or commercial success would adversely affect our results of operations.

We rely on third-party suppliers to manufacture ~~preclinical~~ supplies of our drug candidates and we intend to continue to rely on third parties to produce such preclinical and clinical supplies as well as commercial supplies of any approved product. The loss of these suppliers, or their failure to comply with applicable regulatory requirements or to provide us with sufficient quantities at acceptable quality levels or prices, or at all, would materially and adversely affect our business.

We do not have ~~nor do we plan to build or acquire~~ the infrastructure or capability internally to manufacture supplies of our drug candidates or the materials necessary to produce our drug candidates for use in the conduct of our ~~preclinical studies or~~ clinical studies, and we lack the internal resources and the capability to manufacture any of our drug candidates on a ~~preclinical,~~ clinical or commercial scale. The facilities used by our contract manufacturers to manufacture our drug candidates are subject to various regulatory requirements and may be subject to the inspection of the FDA or other regulatory authorities. We do not control the manufacturing process of, and are completely dependent on, our contract manufacturing partners for compliance with the regulatory requirements, known as cGMPs. If our contract manufacturers cannot successfully manufacture material that conforms to our specifications and the strict regulatory requirements of the FDA or comparable regulatory authorities in foreign jurisdictions, we may not be able to rely on their manufacturing facilities for the manufacture or our drug candidates. In addition, we have limited control over the ability of our contract manufacturers to maintain adequate quality control, quality assurance and qualified personnel. If the FDA or a comparable foreign regulatory authority finds these facilities inadequate for the manufacture of our drug candidates or if such facilities are subject to enforcement action in the future or are otherwise inadequate, we may need to find alternative manufacturing facilities, which would significantly impact our ability to develop, obtain regulatory approval for or market our drug candidates.

We currently intend to supply all of our drug candidates in all territories for our planned clinical development programs. We currently rely on third parties at key stages in our supply chain. For instance, the supply chains for our ~~lead~~current drug candidates involve several manufacturers that specialize in specific operations of the manufacturing process, specifically, raw materials manufacturing, drug substance manufacturing and drug product manufacturing. As a result, the supply chain for the manufacturing of our drug candidates is complicated and we expect the logistical challenges associated with our supply chain to grow more complex as our drug candidates progress through the clinical trial process. Some of these third parties have in the past and may in the future also be adversely impacted by unforeseen events and public health emergencies. For example, one of the manufacturers in our supply chain for

UBX0101 experienced a two-week shutdown in April 2020 due to a COVID-19 related incident. While this incident did not impact our supply of UBX0101 for clinical studies being conducted in April 2020, there can be no assurance that our supply chain for any of our candidates and clinical trials will not be disrupted in the future due to such ~~as UBX0101, commence any clinical studies.~~incidents.

We do not have any control over the process or timing of the acquisition or manufacture of materials by our manufacturers. Further, we have not yet engaged any manufacturers for the commercial supply of our current drug candidates. Although we intend to enter into such agreements prior to commercial launch of any of our drug candidates, we may be unable to enter into any such agreement or do so on commercially reasonable terms, which could have a material adverse impact upon our business. We generally do not begin a preclinical study and we do not intend to initiate any clinical studies unless we believe we have access to a sufficient supply of a drug candidate to complete such study or trial. In addition, any significant delay in, or quality control problems with respect to, the supply of a drug candidate, or the raw material components thereof, for an ongoing study or trial could considerably delay completion of our preclinical studies or future clinical studies, product testing and potential regulatory approval of our drug candidates.

We have not yet engaged any manufacturers for the commercial supply of our drug candidates. Although we intend to enter into such agreements prior to commercial launch of any of our drug candidates, we may be unable to enter into any such agreement or do so on commercially reasonable terms, which could have a material adverse impact upon our business. Moreover, if there is a disruption to one or more of our third-party manufacturers’ or suppliers’

relevant operations, or if we are unable to enter into arrangements for the commercial supply of our drug candidates, we will have no other means of producing our ~~lead~~current drug candidates until they restore the affected facilities or we or they procure alternative manufacturing facilities or sources of supply. Our ability to progress our preclinical and clinical programs could be materially and adversely impacted if any of the ~~third party~~third-party suppliers upon which we rely were to experience a significant business challenge, disruption or failure due to issues such as financial difficulties or bankruptcy, issues relating to other customers such as regulatory or quality compliance issues, or other financial, legal, regulatory or reputational issues.

Additionally, any damage to or destruction of our third-party manufacturers’ or suppliers’ facilities or equipment may significantly impair our ability to manufacture our drug candidates on a timely basis.

~~In addition,~~Further, to manufacture our ~~lead~~current drug candidates in the quantities that we believe would be required to meet anticipated market demand, our third-party manufacturers would likely need to increase manufacturing capacity and, in some cases, we ~~plan~~would need to secure alternative sources of commercial supply, which could involve significant challenges and may require additional regulatory approvals. In addition, the development of commercial-scale manufacturing capabilities may require us and our third-party manufacturers to invest substantial additional funds and hire and retain the technical personnel who have the necessary manufacturing experience. Neither we nor our third-party manufacturers may successfully complete any required increase to existing manufacturing capacity in a timely manner, or at all. If our manufacturers or we are unable to purchase the raw materials necessary for the manufacture of our drug candidates on acceptable terms, at sufficient quality levels, or in adequate quantities, if at all, the commercial launch of our ~~lead~~current drug candidates or any future drug candidates would be delayed or there would be a shortage in supply, which would impair our ability to generate revenues from the sale of such drug candidates, if approved.

If we fail to attract and retain key personnel, we may be unable to successfully develop our current drug candidates or any future drug candidates, conduct our clinical studies and commercialize our current or any future drug candidates.

Our success depends in part on our continued ability to attract, retain and motivate highly qualified management and employees. In February 2022, and again on May 4, 2023, we announced restructuring actions to advance corporate strategy and focus on key ophthalmology programs and, as of May 2023, the UBX1325 program in DME in particular. As a result of the restructuring and other factors, additional unplanned loss of personnel may occur despite our efforts to retain management and employees. Additionally, continued disruption caused by the transition or by the loss of ongoing services of any other members of our management or employees could delay or prevent the successful development of our ongoing programs, initiation or completion of our planned clinical studies or the commercialization of our current drug candidates or any future drug candidates. Competition for qualified personnel in the biotechnology and pharmaceuticals field is intense due to the limited number of individuals who possess the skills and experience required by our industry, and we may not be able to adequately address attrition, including unplanned, attrition, and as a result, the timely completion of our clinical trials could be jeopardized. Further, our ability to attract and retain highly qualified management and employees relies in part on our ability to offer competitive compensation and equity packages to such key personnel. We use restricted stock units, or RSUs, and

stock options as a key component of compensation for key employees in order to align employee interests with the interests of our stockholder, provide competitive compensation packages, and encourage employee retention. Our stock price volatility or lack of positive performance may cause periods of time during which option exercise prices might be less than the sale price of our common stock or the value of RSUs might be less competitive, which may lessen the retentive attributes of these awards. We are also limited as to the number of equity awards that we may grant under our stock plans, and we are unsure how effective different stock-based awards with different vesting schedules will be to retain key employees. As a result, we may have to incur increased compensation costs, change our equity compensation strategy, or find it difficult to attract, retain and motivate employees.

We depend on third-party suppliers for key raw materials used in our manufacturing processes, and the loss of these third-party suppliers or their inability to supply us with adequate raw materials could harm our business.

We rely on third-party suppliers for the raw materials required for the production of our drug candidates. Our dependence on these third-party suppliers and the challenges we may face in obtaining adequate supplies of raw materials involve several risks, including limited control over pricing, availability, and quality and delivery schedules. As a small company, our negotiation leverage is limited, and we are likely to get lower priority than our competitors who are larger than we are. We cannot be certain that our suppliers will continue to provide us with the quantities of these raw materials that we require or satisfy our anticipated specifications and quality requirements. Any supply interruption in limited or sole sourced raw materials could materially harm our ability to manufacture our drug candidates until a new source of supply, if any, could be identified and qualified. We may be unable to find a sufficient alternative supply channel in a reasonable time or on commercially reasonable terms. Any performance failure on the part of our suppliers could delay the development and potential commercialization of our drug candidates, including limiting supplies necessary for clinical studies and regulatory approvals, which would have a material adverse effect on our business.

We rely on third parties in the conduct of ~~all~~critical portions of our preclinical studies and intend to rely on third parties in the conduct of ~~all~~critical portions of our future clinical studies. If these third parties do not successfully carry out their contractual duties, fail to comply with applicable regulatory requirements or meet expected deadlines, we may be unable to obtain regulatory approval for our drug candidates. Some of these third parties may also be adversely impacted by unforeseen events and public health emergencies.

We currently do not have the ability to independently conduct preclinical studies that comply with the regulatory requirements known as good laboratory practice, or GLP, requirements. We also do not currently have the ability to independently conduct any clinical studies. The FDA and regulatory authorities in other jurisdictions require us to comply with regulations and standards, commonly referred to as good clinical practice, or GCP, requirements for conducting, monitoring, recording and reporting the results of clinical studies, in order to ensure that the data and results are scientifically credible and accurate and that the trial subjects are adequately informed of the potential risks of participating in clinical studies. We rely on medical institutions, clinical investigators, contract laboratories and other third parties, such as CROs, to conduct GLP-compliant preclinical studies and GCP-compliant clinical studies on our drug candidates properly and on time. While we have agreements governing their activities, we control only certain aspects of their activities and have limited influence over their actual performance. The third

parties with whom we contract for execution of our GLP-compliant preclinical studies and our GCP-compliant clinical studies play a significant role in the conduct of these studies and trials and the subsequent collection and analysis of data. These third parties are not our employees and, except for restrictions imposed by our contracts with such third parties, we have limited ability to control the amount or timing of resources that they devote to our programs. Although we rely on these third parties to conduct our GLP-compliant preclinical studies and GCP-compliant clinical studies, we remain responsible for ensuring that each of our GLP preclinical studies and clinical studies is conducted in accordance with its investigational plan and protocol and applicable laws and regulations, and our reliance on the CROs does not relieve us of our regulatory responsibilities.

Many of the third parties with whom we contract may also have relationships with other commercial entities, potentially including our competitors, for whom they may also be conducting clinical studies or other drug development activities that could harm our competitive position. If the third parties conducting our preclinical studies or our clinical studies do not adequately perform their contractual duties or obligations, experience significant business challenges, disruptions or failures, do not meet expected deadlines, terminate their agreements with us or need to be replaced, or if the quality or accuracy of the data they obtain is compromised due to their failure to adhere to our protocols or to GCPs, or for any other reason, we may need to enter into new arrangements with alternative third parties. This could be difficult, costly or impossible, and our preclinical studies or clinical studies may need to be

extended, delayed, terminated or repeated. As a result, we may not be able to obtain regulatory approval in a timely fashion, or at all, for the applicable drug candidate, our financial results and the commercial prospects for our drug candidates would be harmed, our costs could increase, and our ability to generate revenues could be delayed.

We face significant competition in an environment of rapid technological and scientific change, and our drug candidates, if approved, will face significant competition and our failure to effectively compete may prevent us from achieving significant market penetration. Most of our competitors have significantly greater resources than we do, and we may not be able to successfully compete.

The biotechnology and pharmaceutical industries in particular are characterized by rapidly advancing technologies, intense competition and a strong emphasis on developing proprietary therapeutics. Numerous companies are engaged in the development, patenting, manufacturing and marketing of healthcare products competitive with those that we are developing. We face competition from a number of sources, such as pharmaceutical companies, generic drug companies, biotechnology companies and academic and research institutions, many of which have greater financial resources, marketing capabilities, sales forces, manufacturing capabilities, research and development capabilities, clinical study expertise, intellectual property portfolios, experience in obtaining patents and regulatory approvals for drug candidates and other resources than we do. Some of the companies that offer competing products also have a broad range of other product offerings, large direct sales forces and long-term customer relationships with our target physicians, which could inhibit our market penetration efforts. Mergers and acquisitions in the pharmaceutical industry may result in even more resources being concentrated among a smaller number of our competitors. Smaller or early-stage companies may also prove to be significant competitors, particularly through collaborative arrangements with large and established companies. These competitors also compete with us in recruiting and retaining qualified scientific and management personnel and establishing clinical study sites and patient registration for clinical studies, as well as in acquiring technologies complementary to, or necessary for, our programs. In addition, certain of our drug candidates, if approved, may compete with other products that treat ~~age-associated~~ diseases of aging, including ~~over-the-counter,~~over the counter, or OTC, treatments, for a share of some patients’ discretionary budgets and for physicians’ attention within their clinical practices.

We are aware of other companies seeking to develop treatments to prevent or treat ~~aging-related~~ diseases of aging through various biological ~~pathways, including Calico and resTORbio.~~pathways. Within our ~~three~~lead senolytic ~~programs,~~program in ophthalmology diseases, our drug candidates would compete against current therapies from a wide range of companies and technologies, ~~including:~~

Certain alternative treatments offered by competitors may be available at lower prices and may offer greater efficacy or better safety profiles. Furthermore, currently approved products could be discovered to have application for treatment of ~~age-associated~~ diseases of aging generally, which could give such products significant regulatory and market timing advantages over any of our drug candidates. Our competitors also may obtain FDA, EMA or other regulatory approval for their products more rapidly than we may obtain approval for ours and may obtain orphan product exclusivity from the FDA for indications our drug candidates are targeting, which could result in our competitors establishing a strong market position before we are able to enter the market. Newly developed systemic or non-systemic treatments that replace existing therapies that currently are ~~currently~~ only utilized in patients suffering from severe disease may also have lessened side effects or reduced prices compared to current therapies, which make them more attractive for patients suffering from mild to moderate disease. Even if a generic ~~product~~ or an OTC product is less effective than our drug candidates, ~~a less effective generic or OTC product~~it may be more quickly adopted by physicians and patients than our competing drug candidates based upon cost or convenience. ~~For additional information regarding our competition, see the section of this prospectus captioned “Business—Competition.”~~

The successful commercialization of our drug candidates will depend in part on the extent to which governmental authorities and health insurers establish adequate coverage, reimbursement levels and pricing policies. Failure to obtain or maintain coverage and adequate reimbursement for our drug candidates, if approved, could limit our ability to market those products and decrease our ability to generate revenue.

The availability and adequacy of coverage and reimbursement by governmental healthcare programs such as Medicare and Medicaid, private health insurers and other third-party payors are essential for most patients to be able to afford prescription medications such as our drug candidates, assuming FDA approval. Our ability to achieve acceptable levels of coverage and reimbursement for products by governmental authorities, private health insurers and other organizations will have an effect on our ability to successfully commercialize our drug candidates. Assuming we obtain coverage for our drug candidates by a third-party payor, the resulting reimbursement payment rates may not be adequate or may require co-payments that patients find unacceptably high. We cannot be sure that coverage and reimbursement in the United States, the EUEuropean Union or elsewhere will be available for our drug candidates or any product that we may develop, and any reimbursement that may become available may be decreased or eliminated in the future.

Third-party payors increasingly are challenging prices charged for pharmaceutical products and services, and many third-party payors may refuse to provide coverage and reimbursement for particular drugs or biologics when an equivalent generic drug, biosimilar or a less expensive therapy is available. It is possible that a third-party payor may consider our drug candidates as substitutable and only offer to reimburse patients for the cost of the less expensive product. Even if we show improved efficacy or improved convenience of administration with our drug candidates, pricing of existing ~~third- party~~third-party therapeutics may limit the amount we will be able to charge for our drug candidates. These payors may deny or revoke the reimbursement status of a given product or establish prices for new or existing marketed products at levels that are too low to enable us to realize an appropriate return on our investment in our drug candidates. If reimbursement is not available or is available only at limited levels, we may not be able to successfully commercialize our drug candidates and may not be able to obtain a satisfactory financial return on our investment in the development of drug candidates.

There is significant uncertainty related to the insurance coverage and reimbursement of ~~newly-~~newly approved products. In the United States, third-party payors, including private and governmental payors, such as the Medicare and Medicaid programs, play an important role in determining the extent to which new drugs and biologics will be covered. The Medicare and Medicaid programs increasingly are used as models in the United States for how private payors and other governmental payors develop their coverage and reimbursement policies for drugs and biologics. Some third-party payors may require pre-approval of coverage for new or innovative devices or drug therapies before they will reimburse healthcare providers who use such therapies. We cannot predict at this time what third-party payors will decide with respect to the coverage and reimbursement for our drug candidates.

No uniform policy for coverage and reimbursement for products exists among third-party payors in the United States. Therefore, coverage and reimbursement for products can differ significantly from payor to payor. As a result, the coverage determination process is often a time-consuming and costly process that will require us to provide scientific and clinical support for the use of our drug candidates to each payor separately, with no assurance that coverage and adequate reimbursement will be applied consistently or obtained in the first instance. Furthermore, rules and regulations regarding reimbursement change frequently, in some cases on short notice, and we believe that changes in these rules and regulations are likely.

Outside the United States, international operations are generally subject to extensive governmental price controls and other market regulations, and we believe the increasing emphasis on cost-containment initiatives in Europe and other countries have and will continue to put pressure on the pricing and usage of our drug candidates. In many countries, the prices of medical products are subject to varying price control mechanisms as part of national health systems. Other countries allow companies to fix their own prices for medical products but monitor and control company profits.

Additional foreign price controls or other changes in pricing regulation could restrict the amount that we are able to charge for our drug candidates. Accordingly, in markets outside the United States, the reimbursement for our drug candidates may be reduced compared with the United States and may be insufficient to generate ~~commercially-reasonable~~commercially reasonable revenue and profits.

Moreover, increasing efforts by governmental and third-party payors in the United States and abroad to cap or reduce healthcare costs may cause such organizations to limit both coverage and the level of reimbursement for newly approved products and, as a result, they may not cover or provide adequate payment for our drug candidates. We expect to experience pricing pressures in connection with the sale of our drug candidates due to the trend toward managed health care, the increasing influence of health maintenance organizations and additional legislative changes. The downward pressure on healthcare costs in general, particularly prescription drugs and biologics and surgical

procedures and other treatments, has become intense. As a result, increasingly high barriers are being erected to the entry of new products.

We currently have no sales organization. If we are unable to establish sales capabilities on our own or through third parties, we may not be able to market and sell our drug candidates effectively in the ~~United States~~U.S. and foreign jurisdictions, if approved, or generate product revenue.

We currently do not have a marketing or sales organization. In order to commercialize our drug candidates in the United States and foreign jurisdictions, we must build our marketing, sales, distribution, managerial and other non-technical capabilities or make arrangements with third parties to perform these services, and we may not be successful in doing so. If any of our drug candidates receive regulatory approval, we expect to establish a sales organization with technical expertise and supporting distribution capabilities to commercialize each such drug candidate, which will be expensive and time consuming. We have no prior experience in the marketing, sale and distribution of pharmaceutical products and there are significant risks involved in building and managing a sales organization, including our ability to hire, retain, and incentivize qualified individuals, generate sufficient sales leads, provide adequate training to sales and marketing personnel, and effectively manage a geographically dispersed sales and marketing team. Any failure or delay in the development of our internal sales, marketing and distribution capabilities would adversely impact the commercialization of these products. We may choose to collaborate with third parties that have direct sales forces and established distribution systems, either to augment our own sales force and distribution systems or in lieu of our own sales force and distribution systems. If we are unable to enter into such arrangements on acceptable terms or at all, we may not be able to successfully commercialize our

drug candidates. If we are not successful in commercializing our drug candidates or any future drug candidates, either on our own or through arrangements with one or more third parties, we may not be able to generate any future product revenue and we would incur significant additional losses.

~~We will need to increase the size of our organization, and we may experience difficulties in managing growth.~~

As of March 31, 2108, we had 75 full-time employees. We will need to continue to expand our managerial, operational, finance and other resources in order to manage our operations and clinical studies, continue our development activities and commercialize our lead drug candidates or any future drug candidates. Our management and personnel, systems and facilities currently in place may not be adequate to support this future growth. Our need to effectively execute our growth strategy requires that we:

If we fail to attract and retain senior management and key scientific personnel, we may be unable to successfully develop our lead drug candidates or any future drug candidates, conduct our clinical studies and commercialize our current or any future drug candidates.

Our success depends in part on our continued ability to attract, retain and motivate highly qualified management, clinical and scientific personnel. We are highly dependent upon our senior management, particularly our President, Nathaniel E. David, and our Chief Executive Officer, Keith R. Leonard, as well as our senior scientists and other members of our senior management team. The loss of services of any of these individuals could delay or prevent the successful development of our product pipeline, initiation or completion of our planned clinical studies or the commercialization of our lead drug candidates or any future drug candidates.

Competition for qualified personnel in the biotechnology and pharmaceuticals field is intense due to the limited number of individuals who possess the skills and experience required by our industry. We will need to hire additional personnel as we expand our clinical development and if we initiate commercial activities. We may not be able to attract and retain quality personnel on acceptable terms, or at all. In addition, to the extent we hire personnel from competitors, we may be subject to allegations that they have been improperly solicited or that they have divulged proprietary or other confidential information, or that their former employers own their research output.

If product liability lawsuits are brought against us, we may incur substantial liabilities and may be required to limit commercialization of our current or future drug candidates.

We face an inherent risk of product liability as a result of the clinical testing of our drug candidates and will face an even greater risk if we commercialize any products. For example, we may be sued if any product we develop allegedly causes injury or is found to be otherwise unsuitable during product testing, manufacturing, marketing or sale. Any such product liability claims may include allegations of defects in manufacturing, defects in design, and a failure to warn of dangers inherent in the product, negligence, strict liability, and a breach of warranty. Claims could also be asserted under state consumer protection acts. If we cannot successfully defend ourselves against product liability claims, we may incur substantial liabilities or be required to limit commercialization of our drug candidates.

Even a successful defense would require significant financial and management resources. Regardless of the merits or eventual outcome, liability claims may result in:

Our inability to obtain and maintain sufficient product liability insurance at an acceptable cost and scope of coverage to protect against potential product liability claims could prevent or inhibit the commercialization of our current or any future drug candidates we develop. We currently carry product liability insurance covering our clinical studies. Although we maintain such insurance, any claim that may be brought against us could result in a court judgment or settlement in an amount that is not covered, in whole or in part, by our insurance or that is in excess of the limits of our insurance coverage. Our insurance policies also have various exclusions and deductibles, and we may

be subject to a product liability claim for which we have no coverage. We will have to pay any amounts awarded by a court or negotiated in a settlement that exceed our coverage limitations or that are not covered by our insurance, and we may not have, or be able to obtain, sufficient funds to pay such amounts. Moreover, in the future, we may not be able to maintain insurance coverage at a reasonable cost or in sufficient amounts to protect us against losses. If and when we obtain approval for marketing any of our drug candidates, we intend to expand our insurance coverage to include the sale of such drug candidate; however, we may be unable to obtain this liability insurance on commercially reasonable terms or at all.

Our existing collaborations as well as additional collaboration arrangements that we may enter into in the future may not be successful, which could adversely affect our ability to develop and commercialize our drug candidates.

We utilize external collaborations and currently maintain ~~more than a dozen~~several active early-stage research and discovery focused collaborations. In the future, we may seek additional collaboration arrangements for the commercialization, or potentially for the development, of certain of our drug candidates depending on the merits of retaining commercialization rights for ourselves as compared to entering into collaboration arrangements. To the extent that we decide to enter into additional collaboration agreements in the future, we may face significant competition in seeking appropriate collaborators. Moreover, collaboration arrangements are complex and time-consuming to negotiate, document, implement and maintain and challenging to manage. We may not be successful in our efforts to prudently manage our existing collaborations or to enter new ones should we chose to do so. The terms of new collaborations, or other arrangements that we may establish may not be favorable to us.

The success of our collaboration arrangements will depend heavily on the efforts and activities of our ~~collaborators.~~collaborators and partners. Collaborations are subject to numerous risks, which may include risks that:

Our senolytic medicine platform and any future products that we commercialize could be alleged to infringe patent rights and other proprietary rights of third parties, which may require costly litigation and, if we are not successful, could cause us to pay substantial damages and/or limit our ability to commercialize our products.

Our commercial success depends on our ability to develop, manufacture and market our senolytic medicines and future drug candidates and use our proprietary technology without infringing the patents and other proprietary rights of third parties. Intellectual property disputes can be costly to defend and may cause our business, operating results and financial condition to suffer. We operate in an industry with extensive intellectual property litigation. As the biopharmaceutical and pharmaceutical industries expand and more patents are issued, the risk increases that there may be patents issued to third parties that relate to our products and technology of which we are not aware or that we may need to challenge to continue our operations as currently contemplated.

Whether merited or not, we may face allegations that we have infringed the trademarks, copyrights, patents and other intellectual property rights of third parties, including patents held by our competitors or by non-practicing entities. We may also face allegations that our employees have misappropriated the intellectual property rights of their former employers or other third parties.

Litigation may make it necessary to defend ourselves by determining the scope, enforceability, and validity of third-party proprietary rights, or to establish our proprietary rights. Regardless of whether claims that we are infringing patents or other intellectual property rights have merit, the claims can be time consuming, divert management attention and financial resources and are costly to evaluate and defend. Results of any such litigation are difficult to predict and may require us to stop treating certain conditions, obtain licenses or modify our products and features while we develop non-infringing substitutes, or may result in significant settlement costs. For example, litigation can involve substantial damages for infringement (and if the court finds that the infringement was willful, we could be ordered to pay treble damages and the patent owner’s attorneys’ fees), and the court could prohibit us from selling or licensing our products unless the third-party licenses rights to us, which it is not required to do at a commercially reasonable price or at all. If a license is available from a third party, we may have to pay substantial royalties, upfront fees or grant cross-licenses to intellectual property rights for our products. We may also have to redesign our products so they do not infringe third-party intellectual property rights, which may not be possible at all or may require substantial monetary expenditures and time, during which our products may not be available for manufacture, use, or sale.

In addition, patent applications in the United States and many international jurisdictions are typically not published until 18 months after the filing of certain priority documents (or, in some cases, are not published until they issue as patents) and publications in the scientific literature often lag behind actual discoveries. Thus, we cannot be certain that others have not filed patent applications or made public disclosures relating to our technology or our contemplated technology. A third party may have filed, and may in the future file, patent applications covering our products or technology similar to ours. Any such patent application may have priority over our patent applications or patents, which could further require us to obtain rights to issued patents covering such technologies. If another party has filed a U.S. patent application on inventions similar to ours, depending on whether the timing of the filing date falls under certain patent laws, we may have to participate in a priority contest (such as an interference proceeding) declared by the U.S. Patent and Trademark Office, to determine priority of invention in the United States. The costs of patent and other proceedings could be substantial, and it is possible that such efforts would be unsuccessful if it is determined that the other party had independently arrived at the same or similar invention prior to our own invention, resulting in a loss of our U.S. patent position with respect to such inventions.

or against us, and the outcome of any such litigation could have a material adverse impact on our business, operating results and financial condition. Litigation is inherently unpredictable and outcomes are uncertain. Further, as the costs and outcome of these types of claims and proceedings can vary significantly, it is difficult to estimate potential losses that may occur. Accordingly, we are unable at this time to estimate the effects of these potential future lawsuits on our financial condition, operations or cash flows.

Some of our competitors may be able to sustain the costs of complex patent litigation more effectively than we can because they have substantially greater resources. Even if resolved in our favor, litigation or other legal proceedings relating to intellectual property claims may cause us to incur significant expenses and could distract our technical and management personnel from their normal responsibilities. In addition, there could be public announcements of the results of hearings, motions or other interim proceedings or developments, and if securities analysts or investors perceive these results to be negative, it could have a material adverse effect on the price of our common stock. Finally, any uncertainties resulting from the initiation and continuation of any litigation could have a material adverse effect on our ability to raise the funds necessary to continue our operations.

If we are unable to obtain, maintain and enforce intellectual property protection directed to our senolytic medicine platform and any future technologies that we develop, others may be able to make, use, or sell products substantially the same as ours, which could adversely affect our ability to compete in the market.

As of September 30, 2023, we own, co-own, or have an exclusive license in certain fields of use to more than 150 patents and pending applications in the United States and foreign jurisdictions. This portfolio includes 37 issued and allowed U.S. patents and applications and 50 granted and allowed foreign patents and applications, respectively. A composition of matter patent filing claiming the specific chemical structure of UBX1325 was issued in the U.S. on April 20, 2021, which will extend our loss of exclusivity on this molecule to 2039, not including any patent term adjustment or patent term extensions to which it may be entitled.

We have not pursued or maintained, and may not pursue or maintain in the future, patent protection for our products in every country or territory in which we may sell our products. In addition, we cannot be sure that any of our pending patent applications or pending trademark applications will issue or that, if issued, they will issue in a form that will be advantageous to us. The U.S. Patent and Trademark Office, or the USPTO, international patent offices or judicial bodies may deny or significantly narrow claims made under our patent applications and our issued patents may be successfully challenged, may be designed around, or may otherwise be of insufficient scope to provide us with protection for our commercial products. Further, the USPTO, international trademark offices or judicial bodies may deny our trademark applications and, even if published or registered, these trademarks may not effectively protect our brand and goodwill. Like patents, trademarks also may be successfully opposed or challenged.

We cannot be certain that the steps we have taken will prevent unauthorized use or unauthorized reverse engineering of our technology. Moreover, third parties may independently develop technologies that are competitive with ours and such competitive technologies may or may not infringe our intellectual property. The enforcement of our intellectual property rights also depends on the success of our legal actions against these infringers in the respective country or forum, but these actions may not be successful. As with all granted intellectual property, such intellectual property may be challenged, invalidated or circumvented, may not provide specific protection and/or may not prove to be enforceable in actions against specific alleged infringers.

The market for biopharmaceuticals, pharmaceuticals, and treatments for diseases of aging is highly competitive and subject to rapid technological change. Our success depends, in part, upon our ability to maintain a competitive position in the development and protection of technologies and products for use in these fields and upon our ability to obtain, maintain and enforce our intellectual property rights in connection therewith. We seek to obtain and maintain patents and other intellectual property rights to restrict the ability of others to market products that misappropriate our technology and/or infringe our intellectual property to unfairly and illegally compete with our products. If we are unable to protect our intellectual property and proprietary rights, our competitive position and our business could be harmed, as third parties may be able to make, use, or sell products that are substantially the same as ours without incurring the sizeable development and licensing costs that we have incurred, which would adversely affect our ability to compete in the market.

We use a combination of patents, trademarks, know-how, confidentiality procedures, and contractual provisions to protect our proprietary technology. However, these protections may not be adequate and may not provide us with any competitive advantage. For example, patents may not issue from any of our currently pending or any

future patent applications, and our issued patents and any future patents that may issue may not survive legal challenges to their scope, validity or enforceability, or provide significant protection for us.

If we or one of our current or future collaborators were to initiate legal proceedings against a third party to enforce a patent covering one of our current drug candidates or future drug candidates, the defendant could counterclaim that our patent is invalid and/or unenforceable. In patent litigation in the United States, defendant counterclaims alleging invalidity and/or unenforceability are commonplace.

Grounds for a validity challenge could be an alleged failure to meet any of several statutory requirements, including lack of novelty, obviousness or nonenablement. Grounds for an unenforceability assertion could be an allegation that someone connected with prosecution of the patent withheld relevant information from the USPTO, or made a misleading statement, during prosecution. Third parties may also raise similar claims before the USPTO, even outside the context of litigation. The outcome following legal assertions of invalidity and unenforceability is unpredictable.

With respect to the validity question, for example, we cannot be certain that there is no invalidating prior art, of which we and the patent examiner were unaware during prosecution. If a defendant were to prevail on a legal assertion of invalidity and/or unenforceability, we would lose at least part, and perhaps all, of the patent protection on our drug candidates. Such a loss of patent protection would have a material adverse impact on our business.

Even if our patents are determined by a court to be valid and enforceable, they may not be interpreted sufficiently broadly to prevent others from marketing products similar to ours or designing around our patents. For example, third parties may be able to make products that are similar to ours but that are not covered by the claims of our patents. Third parties may assert that we or our licensors were not the first to make the inventions covered by our issued patents or pending patent applications. The claims of our issued patents or patent applications when issued may not cover our proposed commercial technologies or the future products that we develop. We may not have freedom to commercialize unimpeded by the patent rights of others. Third parties may have dominating, blocking, or other patents relevant to our technology of which we are not aware. There may be prior public disclosures or art that could be deemed to invalidate one or more of our patent claims. Further, we may not develop additional proprietary technologies in the future, and, if we do, they may not be patentable.

Patent law can be highly uncertain and involve complex legal and factual questions for which important principles remain unresolved. In the United States and in many international jurisdictions, policy regarding the breadth of claims allowed in patents can be inconsistent. The U.S. Supreme Court and the Court of Appeals for the Federal Circuit have made, and will likely continue to make, changes in how the patent laws of the United States are interpreted. Similarly, international courts have made, and will likely continue to make, changes in how the patent laws in their respective jurisdictions are interpreted. We cannot predict future changes in the interpretation of patent laws or changes to patent laws that might be enacted into law by U.S. and international legislative bodies. Those changes may materially affect our patents, our ability to obtain patents or the patents and patent applications of our licensors. Patent reform legislation in the United States could increase the uncertainties and costs surrounding the prosecution of our patent applications and the enforcement or defense of our issued patents. For example, on September 16, 2011, the Leahy-Smith America Invents Act, or Leahy-Smith Act, was signed into law. The Leahy-Smith Act included a number of significant changes to U.S. patent law. These include provisions that affect the way patent applications are prosecuted, redefine prior art, may affect patent litigation, and switch the U.S. patent system from a “first-to-invent” system to a “first-to-file” system. Under a “first-to-file” system, assuming the other requirements for patentability are met, the first inventor to file a patent application generally will be entitled to the patent on an invention regardless of whether another inventor had made the invention earlier. The U.S. Patent and Trademark Office recently developed new regulations and procedures to govern administration of the Leahy-Smith Act, and many of the substantive changes to patent law associated with the Leahy-Smith Act, and in particular, the first-to-file provisions, only became effective on March 16, 2013. The Leahy-Smith Act and its implementation could increase the uncertainties and costs surrounding the prosecution of our patent applications and the enforcement or defense of our issued patents, which could have a material adverse effect on our business and financial condition.

In addition, we have a number of international patents and patent applications and expect to continue to pursue patent protection in many of the significant markets in which we intend to do business. The laws of some international jurisdictions may not protect intellectual property rights to the same extent as laws in the United States, and many companies have encountered significant difficulties in obtaining, protecting, and defending such rights in

international jurisdictions. If we encounter such difficulties or we are otherwise precluded from effectively protecting our intellectual property rights in international jurisdictions, our business prospects could be substantially harmed.

Varying filing dates in international countries may also permit intervening third parties to allege priority to certain technology.

Patent terms may be shortened or lengthened by, for example, terminal disclaimers, patent term adjustments, supplemental protection certificates, and patent term extensions. Patent term extensions and supplemental protection certificates, and the like, may be impacted by the regulatory process and may not significantly lengthen the patent term. Non-payment or delay in payment of patent fees or annuities, delay in patent filings or delay in extension filing (including any patent term extension or adjustment filing), whether intentional or unintentional, may also result in the loss of patent rights important to our business. Certain countries have compulsory licensing laws under which a patent owner may be compelled to grant licenses to other parties. In addition, many countries limit the enforceability of patents against other parties, including government agencies or government contractors. In these countries, the patent owner may have limited remedies, which could materially diminish the value of any patents.

In addition to the protection afforded by patents, we rely on confidentiality agreements to protect confidential information and proprietary know-how that is not patentable or that we elect not to patent, processes for which patents are difficult to enforce and any other elements of our drug candidate discovery and development processes that involve proprietary know-how, information or technology that is not covered by patents. We seek to protect our proprietary technology and processes, in part, by entering into confidentiality agreements with our employees, consultants, scientific advisors, and contractors. We cannot guarantee that we have entered into such agreements with each party that may have or have had access to our confidential information or proprietary technology and processes. We also seek to preserve the integrity and confidentiality of our data and other confidential information by maintaining physical security of our premises and physical and electronic security of our information technology systems. While we have confidence in these individuals, organizations and systems, agreements or security measures may be breached and detecting the disclosure or misappropriation of confidential information and enforcing a claim that a party illegally disclosed or misappropriated confidential information is difficult, expensive and time-consuming, and the outcome is unpredictable. Further, we may not be able to obtain adequate remedies for any breach. In addition, our confidential information may otherwise become known or be independently discovered by competitors, in which case we would have no right to prevent them, or those to whom they communicate it, from using that technology or information to compete with us. We may in the future rely on trade secret protection, which would be subject to the risks identified above with respect to confidential information.

Monitoring unauthorized use of our intellectual property is difficult and costly. From time to time, we review our competitors’ products, and may in the future seek to enforce our patents or other rights against potential infringement. However, the steps we have taken to protect our proprietary rights may not be adequate to prevent misappropriation of our intellectual property. We may not be able to detect unauthorized use of, or take appropriate steps to enforce, our intellectual property rights. Our competitors may also independently develop similar technology. Any inability to meaningfully protect our intellectual property could result in competitors offering products that incorporate our product or service features, which could reduce demand for our products. In addition, we may need to defend our patents from third-party challenges, such as (but not limited to) interferences, derivation proceedings, reexamination proceedings, post-grant review, inter partes review, third-party submissions, oppositions, nullity actions or other patent proceedings. We may need to initiate infringement claims or litigation.

Adverse proceedings such as litigation can be expensive, time consuming and may divert the efforts of our technical and managerial personnel, which could in turn harm our business, whether or not we receive a determination favorable to us. In addition, in an infringement proceeding, a court or other judicial body may decide that the patent we seek to enforce is invalid or unenforceable, or may refuse to stop the other party from using the technology at issue on the grounds that the patent in question does not cover the technology in question. An adverse result in any litigation could put one or more of our patents at risk of being invalidated or interpreted narrowly. Some of our competitors may be able to devote significantly more resources to intellectual property litigation and may have significantly broader patent portfolios to assert against us if we assert our rights against them. Further, because of the substantial discovery required in connection with intellectual property litigation, there is a risk that some of our confidential information could be disclosed or otherwise compromised during litigation.

operating expenses. Our operating expenses may fluctuate significantly in the future as a result of a variety of factors, including the costs of preparing, filing, prosecuting, defending, and enforcing patent and trademark claims and other intellectual property-related costs, including adverse proceedings (such as litigation) costs.

Our intellectual property agreements with third parties may be subject to disagreements over contract interpretation, which could narrow the scope of our rights to the relevant intellectual property or technology or increase our financial or other obligations to our licensors.

Certain provisions in our intellectual property agreements may be susceptible to multiple interpretations. The resolution of any contract interpretation disagreement that may arise could affect the scope of our rights to the relevant intellectual property or technology, or affect financial or other obligations under the relevant agreement, either of which could have a material adverse effect on our business, financial condition, results of operations and prospects.

In addition, while it is our policy to require our employees and contractors who may be involved in the conception or development of intellectual property to execute agreements assigning such intellectual property to us, we may be unsuccessful in executing such an agreement with each party who in fact conceives or develops intellectual property that we regard as our own. Our assignment agreements may not be self-executing or may be breached, and we may be forced to bring claims against third parties, or defend claims they may bring against us, to determine the ownership of what we regard as our intellectual property.

If we are unable to protect the confidentiality of our proprietary information and know-how, the value of our technology and products could be adversely affected.

We may not be able to protect our proprietary information and technology adequately. Although we use reasonable efforts to protect our proprietary information, technology, and know-how, our employees, consultants, contractors and outside scientific advisors may unintentionally or willfully disclose our information to competitors. Enforcing a claim that a third party illegally obtained and is using any of our proprietary information, technology or know-how is expensive and time consuming, and the outcome is unpredictable. In addition, courts outside the United States are sometimes less willing to protect proprietary information, technology, and know-how. We rely, in part, on non-disclosure and confidentiality agreements with our employees, consultants and other parties to protect our proprietary information, technology, and know-how. These agreements may be breached and we may not have adequate remedies for any breach. Moreover, others may independently develop similar or equivalent proprietary information, and third parties may otherwise gain access to our proprietary knowledge.

Even if we obtain regulatory approval for a drug candidate, our products will remain subject to regulatory scrutiny.

If our drug candidates are approved, they will be subject to ongoing regulatory requirements for manufacturing, labeling, packaging, storage, advertising, promotion, sampling, record-keeping, conduct of post-marketing studies, and submission of safety, efficacy, and other post-market information, including both federal and state requirements in the United States and requirements of comparable foreign regulatory authorities.

Manufacturers and manufacturers’ facilities are required to comply with extensive FDA and comparable foreign regulatory authority requirements, including ensuring that quality control and manufacturing procedures conform to cGMP regulations. As such, we and our contract manufacturers will be subject to continual review and inspections to assess compliance with cGMP and adherence to commitments made in any approved marketing application. Accordingly, we and others with whom we work must continue to expend time, money, and effort in all areas of regulatory compliance, including manufacturing, production, and quality control.

We will have to comply with requirements concerning advertising and promotion for our products. Promotional communications with respect to prescription drugs and biologics are subject to a variety of legal and regulatory restrictions and must be consistent with the information in the product’s approved label. As such, we may not promote our products for indications or uses for which they do not have approval. The holder of an approved application must submit new or supplemental applications and obtain approval for certain changes to the approved product, product labeling, or manufacturing process. We could also be asked to conduct post-marketing clinical studies to verify the safety and efficacy of our products in general or in specific patient subsets. An unsuccessful post-marketing study or failure to complete such a study could result in the withdrawal of marketing approval.

If a regulatory agency discovers previously unknown problems with a product, such as adverse events of unanticipated severity or frequency, or problems with the facility where the product is manufactured, or disagrees with the promotion, marketing or labeling of a product, such regulatory agency may impose restrictions on that product or us, including requiring withdrawal of the product from the market. If we fail to comply with applicable regulatory requirements, a regulatory agency or enforcement authority may, among other things:

Any government investigation of alleged violations of law could require us to expend significant time and resources in response and could generate negative publicity. Any failure to comply with ongoing regulatory requirements may significantly and adversely affect our ability to commercialize and generate revenue from our products. If regulatory sanctions are applied or if regulatory approval is withdrawn, the value of our company and our operating results will be adversely affected.

Moreover, the policies of the FDA and of other regulatory authorities may change and additional government regulations may be enacted that could prevent, limit or delay regulatory approval of our drug candidates. We cannot predict the likelihood, nature or extent of government regulation that may arise from future legislation or administrative or executive action, either in the United States or abroad.

If we are slow or unable to adapt to changes in existing requirements or the adoption of new requirements or policies, or if we are not able to maintain regulatory compliance, we may be subject to enforcement action, and we may not achieve or sustain profitability.

If any of our small molecule drug candidates obtain regulatory approval, additional competitors could enter the market with generic versions of such drugs, which may result in a material decline in sales of affected products.

Under the Drug Price Competition and Patent Term Restoration Act of 1984, or the Hatch-Waxman Act, a pharmaceutical manufacturer may file an abbreviated new drug application, or ANDA, seeking approval of a generic version of an approved, small molecule innovator product. Under the Hatch-Waxman Act, a manufacturer may also submit a new drug application, or NDA, under section 505(b)(2) of the Federal Food, Drug, and Cosmetic Act that references the FDA’s prior approval of the small molecule innovator product. A 505(b)(2) NDA product may be for a new or improved version of the original innovator product. The Hatch-Waxman Act also provides for certain periods of regulatory exclusivity, which preclude FDA approval (or in some circumstances, FDA filing and review) of an ANDA or 505(b)(2) NDA. In addition to the benefits of regulatory exclusivity, an innovator NDA holder may have patents claiming the active ingredient, product formulation or an approved use of the drug, which would be listed with the product in the FDA publication, “Approved Drug Products with Therapeutic Equivalence Evaluations,” known as the Orange Book. If there are patents listed in the Orange Book for a product, a generic or 505(b)(2) applicant that seeks to market its product before expiration of the patents must include in their applications what is known as a “Paragraph IV” certification, challenging the validity or enforceability of, or claiming non-infringement of, the listed patent or patents. Notice of the certification must be given to the patent owner and NDA holder and if, within 45 days of receiving notice, either the patent owner or NDA holder sues for patent infringement, approval of the ANDA or 505(b)(2) NDA is stayed for up to 30 months.

Accordingly, if any of our small molecule drug candidates, such as UBX1325, are approved, competitors could file ANDAs for generic versions of our small molecule drug products or 505(b)(2) NDAs that reference our small molecule drug products. If there are patents listed for our small molecule drug products in the Orange Book, those ANDAs and 505(b)(2) NDAs would be required to include a certification as to each listed patent indicating whether the ANDA applicant does or does not intend to challenge the patent. We cannot predict which, if any, patents in our current portfolio or patents we may obtain in the future will be eligible for listing in the Orange Book, how any

generic competitor would address such patents, whether we would sue on any such patents, or the outcome of any such suit.

We may not be successful in securing or maintaining proprietary patent protection for products and technologies we develop or license. Moreover, if any of our owned or in-licensed patents that are listed in the Orange Book are successfully challenged by way of a Paragraph IV certification and subsequent litigation, the affected product could immediately face generic competition and its sales would likely decline rapidly and materially.

Any biologic, or large molecule, drug candidates for which we intend to seek approval may face competition sooner than anticipated.

If we are successful in achieving regulatory approval to commercialize any biologic drug candidate faster than our competitors, such drug candidates may face competition from biosimilar products. In the United States, large molecule drug candidates are regulated by the FDA as biologic products subject to approval under the biologics license application, or BLA, pathway. The Biologics Price Competition and Innovation Act of 2009, or BPCIA, creates an abbreviated pathway for the approval of biosimilar and interchangeable biologic products following the approval of an original BLA. The abbreviated regulatory pathway establishes legal authority for the FDA to review and approve biosimilar biologics, including the possible designation of a biosimilar as “interchangeable” based on its similarity to an existing brand product. Under the BPCIA, an application for a biosimilar product cannot be approved by the FDA until 12 years after the original branded product was approved under a BLA. The law is complex and is still being interpreted and implemented by the FDA. As a result, its ultimate impact, implementation, and meaning are subject to uncertainty.

Moreover, the extent to which a biosimilar product, once approved, will be substituted for any one of our reference products in a way that is similar to traditional generic substitution for non-biologic products is not yet clear, and will depend on a number of marketplace and regulatory factors that are still developing. In addition, a competitor could decide to forego the biosimilar approval path and submit a full BLA after completing its own preclinical studies and clinical studies. In such cases, any exclusivity to which we may be eligible under the BPCIA would not prevent the competitor from marketing its product as soon as it is approved.

If competitors are able to obtain marketing approval for biosimilars referencing our large molecule drug candidates, if approved, such products may become subject to competition from such biosimilars, with the attendant competitive pressure and potential adverse consequences. Such competitive products may be able to immediately compete with us in each indication for which our drug candidates may have received approval.

Enacted and future healthcare legislation may increase the difficulty and cost for us to obtain marketing approval of and commercialize our drug candidates and may affect the prices we may set.

In the United States, the European Union and other jurisdictions, there have been, and we expect there will continue to be, a number of legislative and regulatory changes and proposed changes to the healthcare system that could affect our future results of operations. In particular, there have been and continue to be a number of initiatives at the U.S. federal and state levels that seek to reduce healthcare costs and improve the quality of healthcare. For example, in March 2010, the Patient Protection and ACA, as amended by the Health Care and Education Reconciliation Act, or collectively the Affordable Care Act, was enacted, which substantially changed the way healthcare is financed by both governmental and private insurers. Among the provisions of the ACA, those of greatest importance to the pharmaceutical and biotechnology industries include the following:

Sinceits enactment, there have been judicial and Congressional challenges to certain aspects of the Affordable Care Act. For example, the Tax Cuts and Jobs Act of 2017, or the Tax Act, includes a provision repealing, effective January 1, 2019, the tax-based shared responsibility payment imposed by the ACA on certain individuals who fail to maintain qualifying health coverage for all or part of a year that is commonly referred to as the “individual mandate”. In addition, there may be other efforts to challenge, repeal or replace the ACA that may impact our business or financial condition.

In addition, other legislative changes have been proposed and adopted in the United States since the Affordable Care Act was enacted. In August 2011, the Budget Control Act of 2011, among other things, led to aggregate reductions of Medicare payments to providers of 2% per fiscal year. These reductions went into effect in April 2013 and, due to subsequent legislative amendments to the statute, will remain in effect through 2030, with the exception of a temporary suspension from May 1, 2020 through December 31, 2021, unless additional action is taken by Congress. In addition, in January 2013, the American Taxpayer Relief Act of 2012 was signed into law, which, among other things, further reduced Medicare payments to several types of providers, including hospitals, imaging centers and cancer treatment centers, and increased the statute of limitations period for the government to recover overpayments to providers from three to five years.

Individual states in the United States have also become increasingly aggressive in passing legislation and implementing regulations designed to control pharmaceutical and biological product pricing, including price or patient reimbursement constraints, discounts, restrictions on certain product access and marketing cost disclosure and transparency measures, and, in some cases, designed to encourage importation from other countries and bulk purchasing. Legally mandated price controls on payment amounts by third-party payors or other restrictions could harm our business, results of operations, financial condition and prospects. In addition, regional healthcare authorities and individual hospitals are increasingly using bidding procedures to determine what pharmaceutical products and which suppliers will be included in their prescription drug and other healthcare programs. This could reduce the ultimate demand for our drug candidates or put pressure on our product pricing. Moreover, payment methodologies may be subject to changes in healthcare legislation and regulatory initiatives. For example, CMS may develop new payment and delivery models, such as bundled payment models. In addition, recently there has been heightened governmental scrutiny over the manner in which manufacturers set prices for their marketed products.

In the European Union, similar political, economic and regulatory developments may affect our ability to profitably commercialize our drug candidates, if approved. In addition to continuing pressure on prices and cost containment measures, legislative developments at the EU or member state level may result in significant additional requirements or obstacles that may increase our operating costs. The delivery of healthcare in the European Union, including the establishment and operation of health services and the pricing and reimbursement of medicines, is almost exclusively a matter for national, rather than EU, law and policy. National governments and health service providers have different priorities and approaches to the delivery of health care and the pricing and reimbursement of products in that context. In general, however, the healthcare budgetary constraints in most European Union member states have

resulted in restrictions on the pricing and reimbursement of medicines by relevant health service providers. Coupled with ever-increasing EU and national regulatory burdens on those wishing to develop and market products, this could prevent or delay marketing approval of our drug candidates, restrict or regulate post-approval activities and affect our ability to commercialize our drug candidates, if approved. In markets outside of the United States and European Union, reimbursement and healthcare payment systems vary significantly by country, and many countries have instituted price ceilings on specific products and therapies.

We cannot predict the likelihood, nature or extent of government regulation that may arise from future legislation or administrative action in the United States, the European Union or any other jurisdiction. If we or any third parties we may engage are slow or unable to adapt to changes in existing requirements or the adoption of new requirements or policies, or if we or such third parties are not able to maintain regulatory compliance, our drug candidates may lose any regulatory approval that may have been obtained and we may not achieve or sustain profitability.

Our business operations and current and future relationships with investigators, healthcare professionals, consultants, third-party payors, patient organizations and customers will be subject to applicable healthcare regulatory laws, which could expose us to penalties.

Our business operations and current and future arrangements with investigators, healthcare professionals, consultants, third-party payors, patient organizations and customers, may expose us to broadly applicable fraud and abuse and other healthcare laws and regulations. These laws may constrain the business or financial arrangements and relationships through which we conduct our operations, including how we research, market, sell and distribute our drug candidates, if approved.

Ensuring that our internal operations and future business arrangements with third parties comply with applicable healthcare laws and regulations will involve substantial costs. It is possible that governmental authorities will conclude that our business practices do not comply with current or future statutes, regulations, agency guidance or case law involving applicable fraud and abuse or other healthcare laws and regulations. If our operations are found to be in violation of any of the laws described above or any other governmental laws and regulations that may apply to us, we may be subject to significant penalties, including civil, criminal and administrative penalties, damages, fines, exclusion from government-funded healthcare programs, such as Medicare and Medicaid or similar programs in other countries or jurisdictions, disgorgement, individual imprisonment, contractual damages, reputational harm, diminished profits and the curtailment or restructuring of our operations. Further, defending against any such actions can be costly, time-consuming and may require significant personnel resources. Therefore, even if we are successful in defending against any such actions that may be brought against us, our business may be impaired.

U.S. tax legislation and future changes to applicable U.S. tax laws and regulations may have a material adverse effect on our business, financial condition and results of operations.

New income, sales, use or other tax laws, statutes, rules, regulations or ordinances could be enacted at any time, or interpreted, changed, modified or applied adversely to us, any of which could adversely affect our business operations and financial performance. We are currently unable to predict whether such changes will occur and, if so, the ultimate impact on our business. To the extent that such changes have a negative impact on us, our suppliers or our customers, including as a result of related uncertainty, these changes may materially and adversely impact our business, financial condition, results of operations and cash flows.

Our stock price may be volatile and you may not be able to resell shares of our common stock at or above the price you paid.

The trading price of our common stock has been and may continue to be highly volatile and may be subject to wide fluctuations in response to various factors, some of which are beyond our control.

These factors include those discussed in this “Risk Factors” section of this report and others such as:

In addition, the stock markets in general, and the markets for pharmaceutical, biopharmaceutical, and biotechnology stocks in particular, have experienced extreme volatility as a result of the COVID-19 pandemic, economic uncertainty and increased interest rates, inflation, the government closure of Silicon Valley Bank and liquidity concerns at other financial institutions that may be unrelated to the operating performance of the issuer. These broad market fluctuations may adversely affect the trading price or liquidity of our common stock. In the past, when the market price of a stock has been volatile, holders of that stock have sometimes instituted securities class action litigation against the issuer. If any of our stockholders were to bring such a lawsuit against us, we could incur substantial costs defending the lawsuit and the attention of our management would be diverted from the operation of our business.

On October 19, 2022, we effected a 1-for-10 reverse stock split of our common stock seeking to regain compliance with Nasdaq Global Select Market's continued listing standards. As a result of the reverse stock split, the split-adjusted per share market price of our common stock increased and, from October 20, 2022 to November 2, 2022 (10 consecutive business days), the closing bid price of our common stock exceeded $1.00 per share. Accordingly, on November 3, 2022, we received a notice from Nasdaq indicating that we have regained compliance with Listing Rule 5450(a)(1) as of such date. See the risk factor titled “We may not be able to maintain compliance with the continued listing requirements of Nasdaq and, if so, we would be subject to delisting.” for additional information about our ability to maintain compliance with the continued listing requirements of Nasdaq. Although we currently comply with the minimum bid requirement following the reverse stock split, we cannot assure you that we will be able to maintain compliance with the continued listing requirements of Nasdaq and any delisting would adversely affect our stock price and the liquidity of our common stock.

An active, liquid and orderly market for our common stock may not develop and may not be maintained.

Prior to our initial public offering in May 2018, there was no public market for shares of our common stock. Although our common stock is listed on the Nasdaq Global Select Market, an active trading market for our common stock may never be sustained on the Nasdaq Global Select Market or any other exchange in the future. On October 19, 2022, we effected a 1-for-10 reverse stock split of our common stock seeking to bring us into compliance with the minimum required losing bid price for continued listing on the Nasdaq Global Select Market and to regain compliance with Nasdaq Global Select Market's continued listing standards. While we have regained compliance, we cannot assure that we will continue to meet the minimum required closing bid price for continued listing on the Nasdaq Global Select Market in the future or that we will be able to maintain our listing on the Nasdaq Global Select Market or any other exchange. See the risk factor titled “We may not be able to maintain compliance with the continued listing requirements of Nasdaq and, if so, we would be subject to delisting.” for additional information about our ability to maintain compliance with the continued listing requirements of Nasdaq. The lack of an active market may impair your ability to sell your shares at the time you wish to sell them or at a price that you consider reasonable. An inactive market may also impair our ability to raise capital by selling shares and may impair our ability to acquire other businesses, applications, or technologies using our shares as consideration.

If securities or industry analysts do not publish research or reports about our business, or if they issue an adverse or misleading opinion regarding our stock, our stock price and trading volume could decline.

The trading market for our common stock is influenced by the research and reports that industry or securities analysts publish about us or our business. In the event any of the analysts who cover us issue an adverse or misleading opinion regarding us, our business model, our intellectual property or our stock performance, or if our clinical studies and operating results fail to meet the expectations of analysts, our stock price would likely decline. If one or more of these analysts cease coverage of us or fail to publish reports on us regularly, we could lose visibility in the financial markets, which in turn could cause our stock price or trading volume to decline. If our public float stays below $75.0 million, the risk that analysts cease to cover our stock may increase.

If we sell shares of our common stock in future financings, stockholders may experience immediate dilution and, as a result, our stock price may decline.

We may from time to time issue additional shares of common stock at a discount from the current trading price of our common stock. As a result, our stockholders would experience immediate dilution upon the purchase of any shares of our common stock sold at such discount. For example, we may issue additional shares from time to time pursuant to our shelf registration statements and ATM Offering Programs. In addition, as opportunities present themselves, we may enter into financing or similar arrangements in the future, including the issuance of debt securities, preferred stock or common stock. However, for so long as our public float is less than $75.0 million, under our shelf registration statements, we may not sell more than the equivalent of one-third of our public float during any 12 consecutive months pursuant to the baby shelf rules.

On September 29, 2021, we entered into a Purchase Agreement with Lincoln Park Capital Fund, LLC, under which we may at our discretion sell up to $30.0 million shares of our common stock, subject to certain daily limits, applicable prices, and conditions. As of December 31, 2021, we issued and sold 417,286 shares of our common stock under our Purchase Agreement with Lincoln Park amounting to $8.3 million in gross proceeds. In addition, under the Purchase Agreement, we issued 25,244 shares of our common stock to Lincoln Park as consideration for its commitment to purchase shares of our common stock under the Purchase Agreement.

We generally have the right to control the timing and amount of any future sales of our common stock to Lincoln Park. Sales of shares of our common stock, if any, to Lincoln Park will depend upon market conditions and other factors to be determined by us. We may ultimately decide to sell to Lincoln Park all, some or none of the additional shares of our common stock that may be available for us to sell under the Purchase Agreement. If and when we do sell shares of our common stock to Lincoln Park, after Lincoln Park has acquired the shares of common stock, Lincoln Park may resell all, some or none of those shares of common stock at any time or in its discretion. The sale by Lincoln Park of a substantial number of shares of our common stock issued by us to Lincoln Park under the Purchase Agreement or the anticipation of such sales, could make it more difficult for us to sell equity or equity-related securities in the future at a time and at a price that we might otherwise wish to effect sales.

Sales of substantial amounts of shares of our common stock or other securities by our stockholders, by us under our shelf registration statements or the ATM Offering Programs, or otherwise or by Lincoln Park or through the Hercules Amendment or through any other means could also lower the market price of our common stock and impair our ability to raise capital through the sale of equity or equity-related securities.

Our ability to use our net operating loss carryforwards and certain other tax attributes may be limited.

We have incurred substantial losses during our history and may never achieve profitability. To the extent that we continue to generate taxable losses, unused losses will carry forward to offset a portion of future taxable income, if any, until such unused losses expire, if ever. Under Sections 382 and 383 of the Internal Revenue Code of 1986, as amended, if a corporation undergoes an “ownership change,” generally defined as a greater than 50 percentage point change (by value) in its equity ownership by certain stockholders over a three-year period, the corporation’s ability to use its pre-change net operating loss carryforwards, or NOLs, and other pre-change tax attributes (such as research and development tax credits) to offset its post-change income or taxes may be limited. We may have experienced ownership changes in the past and may experience ownership changes in the future as a result of subsequent shifts in our stock ownership (some of which shifts are outside our control). As a result, if we earn net taxable income, our ability to use our pre-change NOLs to offset such taxable income could be subject to limitations. Similar provisions of state tax law may also apply. As a result, even if we achieve profitability, we may be unable to use a material portion of our NOLs and other tax attributes.

Provisions in our charter documents and under Delaware law could discourage a takeover that stockholders may consider favorable and may lead to entrenchment of management.

Our amended and restated certificate of incorporation and amended and restated bylaws contain provisions that could delay or prevent changes in control or changes in our management without the consent of our board of directors. These provisions include the following:

holder of 15% or more of its capital stock unless the holder has held the stock for three years or, among other exceptions, the board of directors has approved the transaction.

Claims for indemnification by our directors and officers may reduce our available funds to satisfy successful third-party claims against us and may reduce the amount of money available to us.

Our amended and restated certificate of incorporation and amended and restated bylaws provide that we will indemnify our directors and officers, in each case to the fullest extent permitted by Delaware law.

In addition, as permitted by Section 145 of the Delaware General Corporation Law, our amended and restated bylaws and our indemnification agreements that we have entered into with our directors and officers provide that:

We do not currently intend to pay dividends on our common stock, and, consequently, your ability to achieve a return on your investment will depend on appreciation in the price of our common stock.

We do not currently intend to pay any cash dividends on our common stock for the foreseeable future. We currently intend to invest our future earnings, if any, to fund our growth. Therefore, you are not likely to receive any dividends on your common stock for the foreseeable future. Since we do not intend to pay dividends, your ability to receive a return on your investment will depend on any future appreciation in the market value of our common stock. There is no guarantee that our common stock will appreciate or even maintain the price at which our holders have purchased it.

Unfavorable global economic or political conditions could adversely affect our business, financial condition or results of operations.

Our results of operations could be adversely affected by general conditions in the global economy and in the global financial markets. Furthermore, the market for products with the potential to treat ~~age-associated~~ diseases of aging, particularly those affecting large populations in a wide range of geographic locations, may be particularly vulnerable to unfavorable economic conditions. A global financial crisis or a global or regional political disruption, including most recently as a result of the COVID-19 pandemic, have caused and could continue to cause extreme volatility in the capital and credit markets. A severe or prolonged economic downturn or political disruption could result in a variety of risks to our business, including weakened demand for our ~~lead~~current drug candidates or any future drug candidates, if approved, and our ability to raise additional capital when needed on acceptable terms, if at all. A weak or declining economy or political disruption could also strain our manufacturers or suppliers, possibly resulting in supply disruption, or cause our customers to delay making payments for our services. Weakened or declining economic

conditions could be caused by a number of factors, including high interest rates, rising inflation, the government closure of Silicon Valley Bank and liquidity concerns at other financial institutions, and the potential for local and/or global economic recession. Any of the foregoing could harm our business and we cannot anticipate all of the ways in which the political or economic climate and financial market conditions could adversely impact our business.

We or the third parties upon whom we depend may be adversely affected by earthquakes, or other natural disasters or unforeseen pandemics and public health emergencies, such as the COVID-19 pandemic, and our business continuity and disaster recovery plans may not adequately protect us from a serious disaster.

Our corporate headquarters and other facilities are located in the San Francisco Bay Area, which in the past has experienced both severe earthquakes and wildfires. ~~We do not~~Although we carry earthquake ~~insurance.~~insurance, it is limited in scope. Earthquakes, wildfires or other natural disasters could severely disrupt our operations, and have a material adverse effect on our business, results of operations, financial condition and prospects.

If a natural disaster, power outage or other event occurred that prevented us from using all or a significant portion of our headquarters, that damaged critical infrastructure, such as our enterprise financial systems or manufacturing resource planning and enterprise quality systems, or that otherwise disrupted operations, it may be difficult or, in certain cases, impossible, for us to continue our business for a substantial period of time. The disaster recovery and business continuity plans we have in place currently are limited and are unlikely to prove adequate in the event of a serious disaster or similar event. We may incur substantial expenses as a result of the limited nature of our disaster recovery and business continuity plans, which, particularly when taken together with our lack of earthquake insurance, could have a material adverse effect on our business. Measures taken in response to a pandemic, such as the COVID-19 pandemic, which causes a public health emergency, could also disrupt our operations, and have a material adverse effect on our business, results of operations, financial condition and prospects. For example, in mid-March 2020, in alignment with federal, state and local guidance designed to slow the spread of COVID-19, we transitioned to a remote work plan and reduced onsite staffing model for all employees who could not perform their work from home, such as our laboratory, operations, and facilities staff. In the future, we may be required to take actions that could impact our operations if required by applicable laws or regulations or if we determine them to be in the best interests of our employees.

Furthermore, integral parties in our supply chain are similarly vulnerable to natural disasters or other sudden, unforeseen and severe adverse events. If such an event were to affect our supply chain, it could have a material adverse effect on our business.

Significant disruptions of information technology systems or ~~breaches of data security~~deficiencies in our cybersecurity could materially adversely affect our business, results of operations and financial condition.

We collect and maintain information in digital form that is necessary to conduct our business, and we are increasingly dependent on information technology systems and infrastructure to operate our business. In the ordinary course of our business, we collect, store and transmit large amounts of confidential information, including intellectual property, proprietary business information and personal information. It is critical that we do so in a secure manner to maintain the confidentiality and integrity of such confidential information. We have established physical, electronic and organizational measures to safeguard and secure our systems to prevent a data compromise, and rely on commercially available systems, software, tools, and monitoring to provide security for our information technology systems and the processing, transmission and storage of digital information. We have also outsourced elements of our information technology infrastructure, and as a result a number of third-party vendors may or could have access to our confidential information.

Our ~~internal~~ information technology systems and infrastructure, and those of our current and any future collaborators, contractors and consultants and other third parties on which we rely, are vulnerable to attack, interruption and damage from computer viruses, malware (e.g. ransomware), natural disasters, terrorism, war, telecommunication and electrical failures, ~~cyber-attacks~~cyberattacks or cyber-intrusions over the Internet, ~~attachments to emails,~~phishing attacks and other social engineering schemes, employee theft or misuse, human error, fraud, denial or degradation of service attacks, sophisticated nation-state and nation-state-supported actors or unauthorized access or use by persons inside our organization, or persons with access to systems inside our organization.

The risk of a security breach or disruption, particularly through ~~cyber-attacks~~cyberattacks or ~~cyber intrusion,~~cyber-intrusion, including by computer hackers, “phishing” attacks, foreign governments and cyber terrorists, has generally increased as the number,

intensity and sophistication of attempted attacks and intrusions from around the world have increased. In addition, the prevalent use of mobile devices that access confidential information increases the risk of data security breaches, which could lead to the loss of confidential information or other intellectual property. We may face increased cybersecurity risks due to our reliance on internet technology and the number of our employees that work or may work remotely, which may create additional opportunities for cybercriminals to exploit vulnerabilities.

Furthermore, because the techniques used to obtain unauthorized access to, or to sabotage, systems change frequently and often are not recognized until launched against a target, we may be unable to anticipate these techniques or implement adequate preventative measures. We may also experience security breaches that may remain undetected for an extended period. Even if identified, we may be unable to adequately investigate or remediate incidents or breaches due to attackers increasingly using tools and techniques that are designed to circumvent controls, to avoid detection, and to remove or obfuscate forensic evidence. The costs to us to mitigate network security problems, bugs, viruses, worms, malicious software programs and security vulnerabilities could be significant, and while we have implemented security measures to protect our data security and information technology systems, our efforts to address these problems may not be successful, and these problems could result in unexpected interruptions, delays, cessation of service and other harm to our business and our competitive position. If

We and certain of our service providers are from time to time subject to cyberattacks and security incidents.While we do not believe that we have experienced any significant system failure, accident or security breach to date, if such an event were to occur and cause interruptions in our operations, it could result in a material disruption of our product development programs. For example, the loss of clinical study data from completed or ongoing or planned clinical studies could result in delays in our regulatory approval efforts and significantly increase our costs to recover or reproduce the data.

Moreover, if a ~~computer~~ security breach affects our systems, or those of our current and any future collaborators, contractors and consultants and other third parties on which we rely, or results in the unauthorized release of personally identifiable information, our reputation could be materially damaged. In addition, such a breach may require notification to governmental agencies, the media or individuals pursuant to various federal and state privacy and security laws, if applicable, including the Health Insurance Portability and Accountability Act of 1996, as amended by the Health Information Technology for Clinical Health Act of 2009, and its implementing rules and regulations, as well as regulations promulgated by the Federal Trade Commission and state breach notification laws. We would also be exposed to a risk of loss or litigation and potential liability, which could materially adversely affect our business, results of operations and financial condition. Wemaintain cyber liability insurance; however, this insurance may not be sufficient to cover the financial, legal, business or reputational losses that may result from an interruption or breach of our systems.

Our employees and independent contractors, including principal investigators, consultants, commercial collaborators, service providers and other vendors may engage in misconduct or other improper activities, including noncompliance with regulatory standards and requirements, which could have an adverse effect on our results of operations.

We are exposed to the risk that our employees and independent contractors, including principal investigators, consultants, any future commercial collaborators, service providers and other vendors may engage in misconduct or other illegal activity. Misconduct by these parties could include intentional, reckless and/or negligent conduct or other unauthorized activities that violate the laws and regulations of the FDA and other similar regulatory bodies, including those laws that require the reporting of true, complete and accurate information to such regulatory bodies; manufacturing standards; U.S. federal and state healthcare fraud and abuse, data privacy laws and other similar non-U.S. laws; or laws that require the true, complete and accurate reporting of financial information or data. Activities subject to these laws also involve the improper use or misrepresentation of information obtained in the course of clinical studies, the creation of fraudulent data in our preclinical studies or clinical studies, or illegal misappropriation of product, which could result in regulatory sanctions and cause serious harm to our reputation. It is not always possible to identify and deter misconduct by employees and other third-parties, and the precautions we take to detect and prevent this activity may not be effective in controlling unknown or unmanaged risks or losses or in protecting us from governmental investigations or other actions or lawsuits stemming from a failure to be in compliance with such laws or regulations. In addition, we are subject to the risk that a person or government could allege such fraud or other misconduct, even if none occurred. If any such actions are instituted against us, and we are not successful in defending ourselves or asserting our rights, those actions could have a significant impact on our business and financial results, including, without limitation, the imposition of significant civil, criminal and administrative penalties, damages, monetary fines, disgorgements, possible exclusion from participation in Medicare, Medicaid and other U.S. healthcare programs, individual imprisonment, other sanctions, contractual damages, reputational harm, diminished profits and

future earnings and curtailment of our operations, any of which could adversely affect our ability to operate our business and our results of operations.

Our business involves the use of hazardous materials, and we and our third-party manufacturers and suppliers must comply with environmental laws and regulations, which can be expensive and restrict how we do business.

Our research and development activities and our third-party manufacturers’ and suppliers’ activities involve the controlled storage, use and disposal of hazardous materials owned by us, including the components of our product and drug candidates and other hazardous compounds. We and any third-party manufacturers and suppliers we engage are subject to numerous federal, state and local environmental, health and safety laws, regulations and permitting requirements, including those governing laboratory procedures; the generation, handling, use, storage, treatment, and disposal of hazardous and regulated materials and wastes; the emission and discharge of hazardous materials into the ground, air and water; and employee health and safety. Our operations involve the use of hazardous and flammable materials, including chemicals and biological and radioactive materials. Our operations also produce hazardous waste. In some cases, these hazardous materials and various wastes resulting from their use are stored at our and our manufacturers’ facilities pending their use and disposal. We generally contract with third parties for the disposal of these materials and wastes. We cannot eliminate the risk of contamination, which could cause an interruption of our commercialization efforts, research and development efforts and business operations, environmental damage resulting in costly clean-up and liabilities under applicable laws and regulations governing the use, storage, handling and disposal of these materials and specified waste products.

Although we believe that the safety procedures utilized by our third-party manufacturers for handling and disposing of these materials generally comply with the standards prescribed by these laws and regulations, we cannot guarantee that this is the case or eliminate the risk of accidental contamination or injury from these materials. Under certain environmental laws, we could be held responsible for costs relating to any contamination at our current or past facilities and at third-party facilities. In such an event, we may be held liable for any resulting damages and such liability could exceed our resources and state or federal or other applicable authorities may curtail our use of certain materials and/or interrupt our business operations. Furthermore, environmental laws and regulations are complex, change frequently and have tended to become more stringent. We cannot predict the impact of such changes and cannot be certain of our future compliance.

Compliance with applicable environmental laws and regulations may be expensive, and current or future environmental laws and regulations may impair our research, product development and manufacturing efforts. In addition, we cannot entirely eliminate the risk of accidental injury or contamination from these materials or wastes. Although we maintain workers’ compensation insurance to cover us for costs and expenses we may incur due to injuries to our employees resulting from the use of hazardous materials, this insurance may not provide adequate coverage against potential liabilities. We do not carry specific biological or hazardous waste insurance coverage, and our property, casualty, and general liability insurance policies specifically exclude coverage for damages and fines arising from biological or hazardous waste exposure or contamination. Accordingly, in the event of contamination or injury, we could be held liable for damages or be penalized with fines in an amount exceeding our resources, and our clinical studies or regulatory approvals could be suspended, which could have a material adverse effect on our business, results of operations and financial condition.

Our senolytic medicine platform and any future products that we commercialize could be alleged to infringe patent rights and other proprietary rights of third parties, which may require costly litigation and, if we are not successful, could cause us to pay substantial damages and/ or limit our ability to commercialize our products.

Litigation may make it necessary to defend ourselves by determining the scope, enforceability and validity of third-party proprietary rights, or to establish our proprietary rights. Regardless of whether claims that we are infringing patents or other intellectual property rights have merit, the claims can be time consuming, divert management attention and financial resources and are costly to evaluate and defend. Results of any such litigation are difficult to predict and may require us to stop treating certain conditions, obtain licenses or modify our products and features while we develop non-infringing substitutes, or may result in significant settlement costs. For example, litigation can involve substantial damages for infringement (and if the court finds that the infringement was willful, we could be ordered to pay treble damages and the patent owner’s attorneys’ fees), and the court could prohibit us from selling or licensing our products unless the third party licenses rights to us, which it is not required to do at a commercially reasonable price or at all. If a license is available from a third party, we may have to pay substantial royalties, upfront fees or grant cross-licenses to intellectual property rights for our products. We may also have to redesign our products so they do not infringe third-party intellectual property rights, which may not be possible at all or may require substantial monetary expenditures and time, during which our products may not be available for manufacture, use, or sale.

In addition, patent applications in the United States and many international jurisdictions are typically not published until 18 months after the filing of certain priority documents (or, in some cases, are not published until they issue as patents) and publications in the scientific literature often lag behind actual discoveries. Thus, we cannot be certain that others have not filed patent applications or made public disclosures relating to our technology or our contemplated technology. A third party may have filed, and may in the future file, patent applications covering our products or technology similar to ours. Any such patent application may have priority over our patent applications or patents, which could further require us to obtain rights to issued patents covering such technologies. If another party has filed a U.S. patent application on inventions similar to ours, depending on whether the timing of the filing date falls under certain patent laws, we may have to participate in a priority contest (such as an interference proceeding) declared by the United States Patent and Trademark Office, to determine priority of invention in the United States. The costs of patent and other proceedings could be substantial, and it is possible that such efforts would be unsuccessful if it is determined that the other party had independently arrived at the same or similar invention prior to our own invention, resulting in a loss of our U.S. patent position with respect to such inventions.

From time to time, we may be subject to legal proceedings and claims in the ordinary course of business with respect to intellectual property. Although we are not currently subject to any claims from third parties asserting infringement of their intellectual property rights, in the future, we may receive claims from third parties asserting infringement of their intellectual property rights. Future litigation may be necessary to establish our intellectual property rights or to defend ourselves by determining the scope, enforceability and validity of third-party intellectual property rights. There can be no assurance with respect to the outcome of any current or future litigation brought by or against us, and the outcome of any such litigation could have a material adverse impact on our business, operating results and financial condition. Litigation is inherently unpredictable and outcomes are uncertain. Further, as the costs and outcome of these types of claims and proceedings can vary significantly, it is difficult to estimate potential losses that may occur. Accordingly, we are unable at this time to estimate the effects of these potential future lawsuits on our financial condition, operations or cash flows.

Some of our competitors may be able to sustain the costs of complex patent litigation more effectively than we can because they have substantially greater resources. Even if resolved in our favor, litigation or other legal proceedings relating to intellectual property claims may cause us to incur significant expenses, and could distract our technical and management personnel from their normal responsibilities. In addition, there could be public announcements of the results of hearings, motions or other interim proceedings or developments, and if securities analysts or investors perceive these results to be negative, it could have a material adverse effect on the price of our common stock.

~~Finally, any uncertainties resulting from the initiation and continuation of any litigation could have a material adverse effect on our ability to raise the funds necessary to continue our operations.~~

We have not pursued or maintained, and may not pursue or maintain in the future, patent protection for our products in every country or territory in which we may sell our products. In addition, we cannot be sure that any of our pending patent applications or pending trademark applications will issue or that, if issued, they will issue in a form that will be advantageous to us. The United States Patent and Trademark Office, or the USPTO, international patent offices or judicial bodies may deny or significantly narrow claims made under our patent applications and our issued patents may be successfully challenged, may be designed around, or may otherwise be of insufficient scope to provide us with protection for our commercial products. Further, the USPTO, international trademark offices or judicial bodies may deny our trademark applications and, even if published or registered, these trademarks may not effectively protect our brand and goodwill. Like patents, trademarks also may be successfully opposed or challenged.

country or forum, but these actions may not be successful. As with all granted intellectual property, such intellectual property may be challenged, invalidated or circumvented, may not provide specific protection and/or may not prove to be enforceable in actions against specific alleged infringers.

The market for biopharmaceuticals, pharmaceuticals and treatments for age-associated diseases is highly competitive and subject to rapid technological change. Our success depends, in part, upon our ability to maintain a competitive position in the development and protection of technologies and products for use in these fields and upon our ability to obtain, maintain and enforce our intellectual property rights in connection therewith. We seek to obtain and maintain patents and other intellectual property rights to restrict the ability of others to market products that misappropriate our technology and/or infringe our intellectual property to unfairly and illegally compete with our products. If we are unable to protect our intellectual property and proprietary rights, our competitive position and our business could be harmed, as third parties may be able to make, use, or sell products that are substantially the same as ours without incurring the sizeable development and licensing costs that we have incurred, which would adversely affect our ability to compete in the market.

We use a combination of patents, trademarks, know-how, confidentiality procedures and contractual provisions to protect our proprietary technology. However, these protections may not be adequate and may not provide us with any competitive advantage. For example, patents may not issue from any of our currently pending or any future patent applications, and our issued patents and any future patents that may issue may not survive legal challenges to their scope, validity or enforceability, or provide significant protection for us.

If we or one of our current or future collaborators were to initiate legal proceedings against a third party to enforce a patent covering one of our lead drug candidates or future drug candidates, the defendant could counterclaim that our patent is invalid and/or unenforceable. In patent litigation in the United States, defendant counterclaims alleging invalidity and/or unenforceability are commonplace.

Grounds for a validity challenge could be an alleged failure to meet any of several statutory requirements, including lack of novelty, obviousness or non-enablement. Grounds for an unenforceability assertion could be an allegation that someone connected with prosecution of the patent withheld relevant information from the USPTO, or made a misleading statement, during prosecution. Third parties may also raise similar claims before the USPTO, even outside the context of litigation. The outcome following legal assertions of invalidity and unenforceability is unpredictable.

Even if our patents are determined by a court to be valid and enforceable, they may not be interpreted sufficiently broadly to prevent others from marketing products similar to ours or designing around our patents. For example, third parties may be able to make product that are similar to ours but that are not covered by the claims of our patents. Third parties may assert that we or our licensors were not the first to make the inventions covered by our issued patents or pending patent applications. The claims of our issued patents or patent applications when issued may not cover our proposed commercial technologies or the future products that we develop. We may not have freedom to commercialize unimpeded by the patent rights of others. Third parties may have dominating, blocking, or other patents relevant to our technology of which we are not aware. There may be prior public disclosures or art that could be deemed to invalidate one or more of our patent claims. Further, we may not develop additional proprietary technologies in the future, and, if we do, they may not be patentable.

laws in their respective jurisdictions are interpreted. We cannot predict future changes in the interpretation of patent laws or changes to patent laws that might be enacted into law by U.S. and international legislative bodies. Those changes may materially affect our patents, our ability to obtain patents or the patents and patent applications of our licensors.

Patent reform legislation in the United States could increase the uncertainties and costs surrounding the prosecution of our patent applications and the enforcement or defense of our issued patents. For example, on September 16, 2011, the Leahy-Smith America Invents Act, or Leahy-Smith Act, was signed into law. The Leahy-Smith Act included a number of significant changes to U.S. patent law. These include provisions that affect the way patent applications are prosecuted, redefine prior art, may affect patent litigation, and switch the U.S. patent system from a “first-to-invent” system to a “first-to-file” system. Under a “first-to-file” system, assuming the other requirements for patentability are met, the first inventor to file a patent application generally will be entitled to the patent on an invention regardless of whether another inventor had made the invention earlier. The United States Patent and Trademark Office recently developed new regulations and procedures to govern administration of the

Leahy-Smith Act, and many of the substantive changes to patent law associated with the Leahy-Smith Act, and in particular, the first-to-file provisions, only became effective on March 16, 2013. The Leahy- Smith Act and its implementation could increase the uncertainties and costs surrounding the prosecution of our patent applications and the enforcement or defense of our issued patents, which could have a material adverse effect on our business and financial condition.

In addition, we have a number of international patents and patent applications, and expect to continue to pursue patent protection in many of the significant markets in which we intend to do business. The laws of some international jurisdictions may not protect intellectual property rights to the same extent as laws in the United States, and many companies have encountered significant difficulties in obtaining, protecting, and defending such rights in international jurisdictions. If we encounter such difficulties or we are otherwise precluded from effectively protecting our intellectual property rights in international jurisdictions, our business prospects could be substantially harmed.

~~Varying filing dates in international countries may also permit intervening third parties to allege priority to certain technology.~~

Patent terms may be shortened or lengthened by, for example, terminal disclaimers, patent term adjustments, supplemental protection certificates, and patent term extensions. Patent term extensions and supplemental protection certificates, and the like, may be impacted by the regulatory process and may not significantly lengthen patent term. Non-payment or delay in payment of patent fees or annuities, delay in patent filings or delay in extension filing (including any patent term extension or adjustment filing), whether intentional or unintentional, may also result in the loss of patent rights important to our business. Certain countries have compulsory licensing laws under which a patent owner may be compelled to grant licenses to other parties. In addition, many countries limit the enforceability of patents against other parties, including government agencies or government contractors. In these countries, the patent owner may have limited remedies, which could materially diminish the value of any patents.

In addition to the protection afforded by patents, we rely on confidentiality agreements to protect confidential information and proprietary know-how that is not patentable or that we elect not to patent, processes for which patents are difficult to enforce and any other elements of our drug candidate discovery and development processes that involve proprietary know-how, information or technology that is not covered by patents. We seek to protect our proprietary technology and processes, in part, by entering into confidentiality agreements with our employees, consultants, scientific advisors and contractors. We cannot guarantee that we have entered into such agreements with each party that may have or have had access to our confidential information or proprietary technology and processes. We also seek to preserve the integrity and confidentiality of our data and other confidential information by maintaining physical security of our premises and physical and electronic security of our information technology systems. While we have confidence in these individuals, organizations and systems, agreements or security measures may be breached and detecting the disclosure or misappropriation of confidential information and enforcing a claim that a party illegally disclosed or misappropriated confidential information is difficult, expensive and time-consuming, and the outcome is unpredictable. Further, we may not be able to obtain adequate remedies for

any breach. In addition, our confidential information may otherwise become known or be independently discovered by competitors, in which case we would have no right to prevent them, or those to whom they communicate it, from using that technology or information to compete with us. We may in the future rely on trade secret protection, which would be subject to the risks identified above with respect to confidential information.

Monitoring unauthorized use of our intellectual property is difficult and costly. From time to time, we review our competitors’ products, and may in the future seek to enforce our patents or other rights against potential infringement. However, the steps we have taken to protect our proprietary rights may not be adequate to prevent misappropriation of our intellectual property. We may not be able to detect unauthorized use of, or take appropriate steps to enforce, our intellectual property rights. Our competitors may also independently develop similar technology. Any inability to meaningfully protect our intellectual property could result in competitors offering products that incorporate our product or service features, which could reduce demand for our products. In addition, we may need to defend our patents from third-party challenges, such as (but not limited to) interferences, derivation proceedings, re-examination proceedings, post-grant review, inter partes review, third-party submissions, oppositions, nullity actions or other patent proceedings. We may need to initiate infringement claims or litigation.

Adverse proceedings such as litigation can be expensive, time consuming and may divert the efforts of our technical and managerial personnel, which could in turn harm our business, whether or not we receive a determination favorable to us. In addition, in an infringement proceeding, a court or other judicial body may decide that the patent we seek to enforce is invalid or unenforceable, or may refuse to stop the other party from using the technology at issue on the grounds that the patent in question does not cover the technology in question. An adverse result in any litigation could put one or more of our patents at risk of being invalidated or interpreted narrowly. Some of our competitors may be able to devote significantly more resources to intellectual property litigation, and may have significantly broader patent portfolios to assert against us if we assert our rights against them. Further, because of the substantial discovery required in connection with intellectual property litigation, there is a risk that some of our confidential information could be disclosed or otherwise compromised during litigation.

We may not be able to correctly estimate or control our future operating expenses in relation to obtaining intellectual property, enforcing intellectual property and/or defending intellectual property, which could affect operating expenses. Our operating expenses may fluctuate significantly in the future as a result of a variety of factors, including the costs of preparing, filing, prosecuting, defending, and enforcing patent and trademark claims and other intellectual property-related costs, including adverse proceedings (such as litigation) costs.

We may be subject to claims challenging the inventorship or ownership of our patents and other intellectual property.

We may also be subject to claims that former employees, collaborators or other third parties have an ownership interest in our patents or other intellectual property. Litigation may be necessary to defend against these and other claims challenging inventorship or ownership. If we fail in defending any such claims, in addition to paying monetary damages, we may lose valuable intellectual property rights. Such an outcome could have a material adverse effect on our business. Even if we are successful in defending against such claims, litigation could result in substantial costs and distraction to management and other employees.

We may not be able to protect our intellectual property rights throughout the world.

Filing, prosecuting and defending patents on drug candidates in all countries throughout the world would be prohibitively expensive, and our intellectual property rights in some countries outside the United States can be less extensive than those in the United States. In addition, the laws of some foreign countries do not protect intellectual

property rights to the same extent as federal and state laws in the United States. Consequently, we may not be able to prevent third parties from practicing our inventions in all countries outside the United States, or from selling or importing products made using our inventions in and into the United States or other jurisdictions. Competitors may use our technologies in jurisdictions where we have not obtained patent protection to develop their own products and further, may export otherwise infringing products to territories where we have patent protection, but enforcement is not as strong as that in the United States. These products may compete with our products and our patents or other intellectual property rights may not be effective or sufficient to prevent them from competing.

Many companies have encountered significant problems in protecting and defending intellectual property rights in foreign jurisdictions. The legal systems of certain countries, particularly certain developing countries, do not favor the enforcement of patents and other intellectual property protection, particularly those relating to biopharmaceuticals, which could make it difficult for us to stop the infringement of our patents or marketing of competing products in violation of our proprietary rights generally. Proceedings to enforce our patent rights in foreign jurisdictions could result in substantial costs and divert our efforts and attention from other aspects of our business, could put our patents at risk of being invalidated or interpreted narrowly and our patent applications at risk of not issuing and could provoke third parties to assert claims against us. We may not prevail in any lawsuits that we initiate, and the damages or other remedies awarded, if any, may not be commercially meaningful.

Accordingly, our efforts to enforce our intellectual property rights around the world may be inadequate to obtain a significant commercial advantage from the intellectual property that we develop or license.

~~If our trademarks~~Actual or perceived failures to comply with U.S. and ~~trade names are not adequately protected, then we~~foreign privacy and data protection laws, regulations and standards may ~~not be able to build name recognition in our markets of interest and~~adversely affect our business, ~~may be adversely affected.~~operations and financial performance.

~~Our registered or unregistered trademarks or trade names may be challenged, infringed, circumvented, declared generic or conflict with third-party rights.~~ We may not be able to protect our rights to these trademarks and trade names, which we need to build name recognition by potential partners or customers in our markets of interest. In addition, third parties may file first for our trademarks in certain countries. If they succeeded in registering such trademarks, and if we were not successful in challenging such third-party rights, we may not be able to use these trademarks to market our products in those countries. In such cases, over the long term, if we are ~~unable to establish name recognition based on our trademarks and trade names, then our marketing abilities may be impacted.~~

~~If we are unable to protect the confidentiality of our proprietary information and know-how, the value of our technology and products could be adversely affected.~~

sometimes less willing to protect proprietary information, technology, and know-how. We rely, in part, on non-disclosure and confidentiality agreements with our employees, consultants and other parties to protect our proprietary information, technology, and know-how. These agreements may be breached and we may not have adequate remedies for any breach. Moreover, others may independently develop similar or equivalent proprietary information, and third parties may otherwise gain access to our proprietary knowledge.

~~Even if we obtain regulatory approval for a drug candidate, our products will remain~~ subject to or affected by numerous federal, state and foreign laws and regulations, as well as regulatory ~~scrutiny.~~

~~If our drug candidates are approved, they will be subject to ongoing regulatory requirements for manufacturing, labeling, packaging, storage, advertising, promotion, sampling, record-keeping, conduct~~guidance, governing the collection, use, disclosure, retention, and security of ~~post-marketing studies,~~personal information, such as information that we collect about patients and ~~submission of safety, efficacy, and other post-market information, including both federal and state requirements~~healthcare providers in connection with clinical trials in the United States and ~~requirements~~abroad. The global data protection landscape is rapidly evolving, and implementation standards and enforcement practices are likely to remain uncertain for the foreseeable future. This evolution may create uncertainty in our business, affect our or any service providers’, contractors’ or future collaborators’ ability to operate in certain jurisdictions or to collect, store, transfer use and share personal information, necessitate the acceptance of ~~comparable foreign regulatory authorities.~~

~~Manufacturers~~more onerous obligations in our contracts, result in liability or impose additional costs on us. The cost of compliance with these laws, regulations and ~~manufacturers’ facilities are required~~standards is high and is likely to increase in the future. Any failure or perceived failure by us or our collaborators, service providers and contractors to comply with ~~extensive FDA~~federal, state or foreign laws or regulation, our internal policies and ~~comparable foreign regulatory authority requirements, including ensuring that quality control and manufacturing~~ procedures ~~conform to cGMP regulations. As such, we and~~or our contract manufacturers will be subject to continual review and inspections to assess compliance with cGMP and adherence to commitments made in any approved marketing application. Accordingly, we and others with whom we work must continue to expend time, money, and effort in all areascontracts governing processing of ~~regulatory compliance, including manufacturing, production, and quality control.~~

We will have to comply with requirements concerning advertising and promotion for our products. Promotional communications with respect to prescription drugs and biologics are subject to a variety of legal and regulatory restrictions and must be consistent with thepersonal information in the product’s approved label. As such, we may not promote our products for indications or uses for which they do not have approval. The holder of an approved application must submit new or supplemental applications and obtain approval for certain changes to the approved product, product labeling, or manufacturing process. We could also be asked to conduct post-marketing clinical studies to verify the safety and efficacy of our products in general or in specific patient subsets. An unsuccessful post-marketing study or failure to complete such a study could result in ~~the withdrawal~~negative publicity, diversion of ~~marketing approval.~~

~~Any government investigation of alleged violations of law could require us to expend significant~~management time and ~~resources in response,~~effort and ~~could generate negative publicity. Any failure to comply with ongoing regulatory requirements may significantly~~proceedings against us by governmental entities or others. In many jurisdictions, enforcement actions and ~~adversely affect our ability to commercialize and generate revenue from our products. If regulatory sanctions~~consequences for noncompliance are ~~applied or if regulatory approval is withdrawn, the value of our company and our operating results will be adversely affected.~~rising.

Namely, the Trump administration has taken several executive actions, including the issuance of a number of Executive Orders, that could impose significant burdens on, or otherwise materially delay, the FDA’s ability to engage in routine oversight activities such as implementing statutes through rulemaking, issuance of guidance, and review and approval of marketing applications. It is difficult to predict how these orders will be implemented, and the extent to which they will impact the FDA’s ability to exercise its regulatory authority. If these executive actions impose restrictions on the FDA’s ability to engage in oversight and implementation activities in the normal course, our business may be negatively impacted. In addition, if we are slow or unable to adapt to changes in existing requirements or the adoption of new requirements or policies, or if we are not able to maintain regulatory compliance, we may lose any marketing approval that we may have obtained and we may not achieve or sustain profitability.

Accordingly, if any of our small molecule drug candidates, such as UBX0101 or UBX1967, are approved, competitors could file ANDAs for generic versions of our small molecule drug products or 505(b)(2) NDAs that reference our small molecule drug products. If there are patents listed for our small molecule drug products in the Orange Book, those ANDAs and 505(b)(2) NDAs would be required to include a certification as to each listed patent indicating whether the ANDA applicant does or does not intend to challenge the patent. We cannot predict which, if any, patents in our current portfolio or patents we may obtain in the future will be eligible for listing in the Orange Book, how any generic competitor would address such patents, whether we would sue on any such patents, or the outcome of any such suit.

~~Any biologic, or large molecule, drug candidates for which we intend to seek approval may face competition sooner than anticipated.~~

~~If we are successful in achieving regulatory approval to commercialize any biologic drug candidate faster than our competitors, such drug candidates may face competition from biosimilar products.~~ In the United States, ~~our large molecule drug candidates are regulated by the FDA as biologic products subject~~HIPAA imposes privacy, security and breach reporting obligations with respect to ~~approval under the biologics license application,~~individually identifiable health information upon “covered entities” (health plans, health care clearinghouses and certain health care providers), and their respective business associates, individuals or ~~BLA, pathway. The Biologics Price Competition and Innovation Act of 2009,~~entities that create, receive, maintain or ~~BPCIA, creates an abbreviated pathway~~transmit protected health information in connection with providing a service for the approval of biosimilar and interchangeable biologic products following the approval of an original BLA. The abbreviated regulatory pathway establishes legal authority for the FDA to review and approve biosimilar biologics, including the possible designationor on behalf of a biosimilar as “interchangeable” based on its similarity to an existing brand product. Under the BPCIA, an application for a biosimilar product cannot be approved by the FDA until 12 years after the original branded product was approved under a BLA. The law is complex and is still being interpreted and implemented by the FDA. As a result, its ultimate impact, implementation, and meaningcovered entity. Most healthcare providers, including research institutions from which we obtain patient health information, are subject to ~~uncertainty.~~privacy and security regulations promulgated under HIPAA. While we do not believe that we are currently acting as a covered entity or business associate under HIPAA and thus are not directly regulated under HIPAA, any person may be prosecuted under HIPAA’s criminal provisions either directly or under aiding-and-abetting or conspiracy principles. Consequently, depending on the facts and circumstances, we could face substantial criminal penalties if we knowingly receive individually identifiable health information from a HIPAA-covered healthcare provider or research institution that has not satisfied HIPAA’s requirements for disclosure of individually identifiable health information.

~~We may seek orphan drug designation for~~ certain future drug candidates, but we may be unable to obtain such designations or to maintain the benefits associated with orphan drug designation, including market exclusivity, which may cause our revenue, if any, to be reduced.

We may pursue orphan drug designation for certain of our future drug candidates. Under the Orphan Drug Act, the FDA may designate a drug or biologic product as an orphan drug if it is intended to treat a rare disease or condition, defined as a patient population of fewer than 200,000 in the United States, or a patient population greater than 200,000 in the United States where there is no reasonable expectation that the cost of developing the drug will be recovered from sales in the United States. In the European Union, the EMA’s Committee for Orphan Medicinal Products, or COMP, grants orphan drug designation to promote the development of products that are intended for the diagnosis, prevention, or treatment of a life-threatening or chronically debilitating condition affecting not more than five in 10,000 persons in the European Union. Additionally, designation is granted for products intended for the diagnosis, prevention, or treatment of a life-threatening, seriously debilitating or serious and chronic condition when, without incentives, it is unlikely that sales of the drug in the European Union would be sufficient to justify the necessary investment in developing the drug or biological product or where there is no satisfactory method of diagnosis, prevention, or treatment, or, if such a method exists, the medicine must be of significant benefit to those affected by the condition.

In the United States, orphan drug designation entitles a party to financial incentives such as opportunities for grant funding towards clinical study costs, tax advantages, and application fee waivers. In addition, if a product receives the first FDA approval for the indication for which it has orphan designation, the product is entitled to orphan drug exclusivity, which means the FDA may not approve any other application to market the same drug for the same

indication for a period of seven years, except in limited circumstances, such as a showing of clinical superiority over the product with orphan exclusivity or where the manufacturer is unable to assure sufficient product quantity for the orphan patient population. In the European Union, orphan drug designation entitles a party to financial incentives such as reduction of fees or fee waivers and ten years of market exclusivity following drug or biological product approval. This period may be reduced to six years if the orphan drug designation criteria are no longer met, including where it is shown that the product is sufficiently profitable not to justify maintenance of market exclusivity.

Even if we obtain orphan drug designation, we may not be the first to obtain marketing approval for any particular orphan indication due to the uncertainties associated with developing pharmaceutical products. Further, even if we obtain orphan drug exclusivity for a drug candidate, that exclusivity may not effectively protect the product from competition because different drugs with different active moieties can be approved for the same condition. Even after an orphan drug is approved, the FDA or EMA can subsequently approve the same drug with the same active moiety for the same condition if the FDA or EMA concludes that the later drug is clinically superior in that it is safer, more effective, or makes a major contribution to patient care. Orphan drug designation neither shortens the development time or regulatory review time of a drug or biologic nor gives the drug or biologic any advantage in the regulatory review or approval process.

~~Enacted and future healthcare legislation may increase the difficulty and cost for us to obtain marketing approval of and commercialize our drug candidates and may affect the prices we may set.~~

In the United States, the EU and other jurisdictions, there have been, and we expect there will continue to be, a number of legislative and regulatory changes and proposed changes to the healthcare system that could affect our future results of operations. In particular, there have been and continue to be a number of initiatives at the U.S. federal and state levels that seek to reduce healthcare costs and improve the quality of healthcare. For example, in March 2010, the Patient Protection and Affordable Care Act, as amended by the Health Care and Education Reconciliation Act, or collectively the Affordable Care Act, was enacted, which substantially changed the way healthcare is financed by both governmental and private insurers. Among the provisions of the Affordable Care Act, those of greatest importance to the pharmaceutical and biotechnology industries include the following:

Since its enactment, there have been judicial and Congressional challenges to certain aspects of the Affordable Care Act, and we expect there will be additional challenges and amendments to the Affordable Care Act in the future. The current presidential administration and Congress will likely continue to seek to modify, repeal, or otherwise invalidate all, or certain provisions of, the Affordable Care Act. It is uncertain the extent to which any such changes may impact our business or financial condition.

In addition, other legislative changes have been proposed and adopted in the United States since the Affordable Care Act was enacted. In August 2011, the Budget Control Act of 2011, among other things, led to aggregate reductions of Medicare payments to providers of 2% per fiscal year. These reductions went into effect in April 2013 and, due to subsequent legislative amendments to the statute, will remain in effect through 2025 unless additional action is taken by Congress. In January 2013, the American Taxpayer Relief Act of 2012 was signed into law, which, among other things, further reduced Medicare payments to several types of providers, including hospitals, imaging centers and cancer treatment centers, and increased the statute of limitations period for the government to recover overpayments to providers from three to five years.

Individual states in the United States have also become increasingly aggressive in passing legislation and implementing regulations designed to control pharmaceutical and biological product pricing, including price or patient reimbursement constraints, discounts, restrictions on certain product access and marketing cost disclosure and transparency measures, and, in some cases, designed to encourage importation from other countries and bulk purchasing. Legally-mandated price controls on payment amounts by third-party payors or other restrictions could harm our business, results of operations, financial condition and prospects. In addition, regional healthcare authorities and individual hospitals are increasingly using bidding procedures to determine what pharmaceutical products and which suppliers will be included in their prescription drug and other healthcare programs. This could reduce the ultimate demand for our drug candidates or put pressure on our product pricing. Moreover, payment methodologies may be subject to changes in healthcare legislation and regulatory initiatives. For example, CMS may develop new payment and delivery models, such as bundled payment models. In addition, recently there has been heightened governmental scrutiny over the manner in which manufacturers set prices for their marketed products.

In the EU, similar political, economic and regulatory developments may affect our ability to profitably commercialize our drug candidates, if approved. In addition to continuing pressure on prices and cost containment measures, legislative developments at the EU or member state level may result in significant additional requirements or obstacles that may increase our operating costs. The delivery of healthcare in the EU, including the establishment and operation of health services and the pricing and reimbursement of medicines, is almost exclusively a matter for national, rather than EU, law and policy. National governments and health service providers have different priorities and approaches to the delivery of health care and the pricing and reimbursement of products in that context. In general, however, the healthcare budgetary constraints in most EU member states have resulted in restrictions on the pricing and reimbursement of medicines by relevant health service providers. Coupled with ever-increasing EU and national regulatory burdens on those wishing to develop and market products, this could prevent or delay marketing

approval of our drug candidates, restrict or regulate post-approval activities and affect our ability to commercialize our drug candidates, if approved. In markets outside of the United States and EU, reimbursement and healthcare payment systems vary significantly by country, and many countries have instituted price ceilings on specific products and therapies.

We cannot predict the likelihood, nature or extent of government regulation that may arise from future legislation or administrative action in the United States, the EU or any other jurisdiction. If we or any third parties we may engage are slow or unable to adapt to changes in existing requirements or the adoption of new requirements or policies, or if we or such third parties are not able to maintain regulatory compliance, our drug candidates may lose any regulatory approval that may have been obtained and we may not achieve or sustain profitability.

~~Ensuring that~~among countries and regions in which we operate, it could affect the manner in which we provide our ~~internal~~services, the geographical location or segregation of our relevant systems and operations, and ~~future business arrangements with third parties~~could adversely affect our financial results.

Further, beginning January 1, 2021, companies have had to comply with ~~applicable healthcare laws~~the GDPR and ~~regulations will involve substantial costs. It is possible that governmental authorities will conclude that our business practices do not comply~~also the United Kingdom GDPR, or UK GDPR, which, together with ~~current~~the amended UK Data Protection Act 2018, retains the GDPR in United Kingdom national law. The UK GDPR mirrors the fines under the GDPR, i.e., fines up to the greater of €20 million (£17.5 million) or ~~future statutes, regulations, agency guidance or case law involving applicable fraud~~4% of global turnover. As we continue to expand into other foreign countries and ~~abuse or other healthcare laws and regulations. If our operations are found~~jurisdictions, we may be subject to ~~be in violation of any of the laws described above or any other governmental~~additional laws and regulations that may ~~apply to us,~~affect how we may be subject to significant penalties, including civil, criminal and administrative penalties, damages, fines, exclusion from government-funded healthcare programs, such as Medicare and Medicaid or similar programs in other countries or jurisdictions, disgorgement, individual imprisonment, contractual damages, reputational harm, diminished profits and the curtailment or restructuring of our operations. Further, defending against any such actions can be costly, time-consuming and may require significant personnel resources. Therefore, even if we are successful in defending against any such actions that may be brought against us, our business may be impaired.conduct business.

~~Recent U.S. tax legislation and future changes to applicable U.S. tax laws and regulations may have a material adverse effect on our business, financial condition and results of operations.~~

Changes in laws and policy relating to taxes may have an adverse effect on our business, financial condition and results of operations. For example, the U.S. government recently enacted significant tax reform, and certain provisions of the new law may adversely affect us. Changes include, but are not limited to, a federal corporate tax

rate decrease to 21% for tax years beginning after December 31, 2017, a reduction to the maximum deduction allowed for net operating losses generated in tax years after December 31, 2017, eliminating carrybacks of net operating losses, and providing for indefinite carryforwards for losses generated in tax years after December 31, 2017. The legislation is unclear in many respects and could be subject to potential amendments and technical corrections, and will be subject to interpretations and implementing regulations by the Treasury and Internal Revenue Service, any of which could mitigate or increase certain adverse effects of the legislation. In addition, it is unclear how these U.S. federal income tax changes will affect state and local taxation. Generally, future changes in applicable U.S. tax laws and regulations, or their interpretation and application could have an adverse effect on our business, financial conditions and results of operations.

~~Our stock price may be volatile and you may not be able to resell shares of our common stock at or above the price you paid.~~

~~The trading price of our common stock may be highly volatile and may be subject to wide fluctuations in response to various factors, some of which are beyond our control.~~

~~These factors include those discussed in this “Risk Factors” section of this report and others such as:~~

In addition, the stock markets in general, and the markets for pharmaceutical, biopharmaceutical, and biotechnology stocks in particular, have experienced extreme volatility that may have been unrelated to the operating performance of the issuer. These broad market fluctuations may adversely affect the trading price or liquidity of our common stock. In the past, when the market price of a stock has been volatile, holders of that stock have sometimes instituted securities class action litigation against the issuer. If any of our stockholders were to bring such a lawsuit against us, we could incur substantial costs defending the lawsuit and the attention of our management would be diverted from the operation of our business.

~~An active, liquid and orderly market for our common stock may not develop, and you may not be able to resell your common stock at or above the public offering price.~~

Prior to our initial public offering in May 2018, there was no public market for shares of our common stock. Our stock only recently began trading on The NASDAQ Global Select Market, but we can provide no assurance that we will be able to maintain an active trading market on The NASDAQ Global Select Market or any other exchange in the future. Even if an active trading market is developed, it may not be sustained. The lack of an active market may impair your ability to sell your shares at the time you wish to sell them or at a price that you consider reasonable. An inactive market may also impair our ability to raise capital by selling shares and may impair our ability to acquire other businesses, applications, or technologies using our shares as consideration.

The trading market for our common stock is influenced by the research and reports that industry or securities analysts publish about us or our business. We do only recently obtained research coverage by securities and industry analysts. If no additional new or few securities or industry analysts commence coverage of us, the trading price for our stock would be negatively impacted. In the event any of the analysts who cover us issue an adverse or misleading opinion regarding us, our business model, our intellectual property or our stock performance, or if our clinical studies and operating results fail to meet the expectations of analysts, our stock price would likely decline. If one or more of these analysts cease coverage of us or fail to publish reports on us regularly, we could lose visibility in the financial markets, which in turn could cause our stock price or trading volume to decline.

We are an “emerging growth company” and as a result of the reduced disclosure and governance requirements applicable to emerging growth companies, our common stock may be less attractive to investors.

reports and proxy statements, and exemptions from the requirements of holding a nonbinding advisory vote on executive compensation and stockholder approval of any golden parachute payments not previously approved. In addition, as an “emerging growth company” the JOBS Act allows us to delay adoption of new or revised accounting pronouncements applicable to public companies until such pronouncements are made applicable to private companies. We have elected to use this extended transition period under the JOBS Act. As a result, our consolidated financial statements may not be comparable to the financial statements of issuers who are required to comply with the effective dates for new or revised accounting standards that are applicable to public companies, which may make comparison of our financials to those of other public companies more difficult.

We cannot predict if investors will find our common stock less attractive because we will rely on these exemptions. If some investors find our common stock less attractive as a result, there may be a less active trading market for our common stock and our stock price may be more volatile. We may take advantage of these reporting exemptions until we are no longer an emerging growth company. We will remain an emerging growth company until the earlier of (1) the last day of the year following the fifth anniversary of the consummation of the offering, (2) the last day of the year in which we have total annual gross revenue of at least $1.07 billion, (3) the last day of the year in which we are deemed to be a “large accelerated filer” as defined in Rule 12b-2 under the Exchange Act, which would occur if the market value of our common stock held by non-affiliates exceeded $700.0 million as of the last business day of the second fiscal quarter of such year or (4) the date on which we have issued more than $1.0 billion in non-convertible debt securities during the prior three-year period.

~~If we sell shares of our common stock in future financings, stockholders may experience immediate dilution and, as a result, our stock price may decline.~~

We may from time to time issue additional shares of common stock at a discount from the current trading price of our common stock. As a result, our stockholders would experience immediate dilution upon the purchase of any shares of our common stock sold at such discount. In addition, as opportunities present themselves, we may enter into financing or similar arrangements in the future, including the issuance of debt securities, preferred stock or common stock. If we issue common stock or securities convertible into common stock, our common stockholders would experience additional dilution and, as a result, our stock price may decline

~~Our principal stockholders and management own a significant percentage of our stock and will be able to exert significant control over matters subject to stockholder approval.~~

As of April 11, 2018, our executive officers, directors, holders of 5% or more of our capital stock and their respective affiliates beneficially owned approximately 66.1% of our voting stock, after giving effect to the closing of our initial public offering. Therefore, these stockholders have the ability to influence us through this ownership position. These stockholders may be able to determine all matters requiring stockholder approval. For example, these stockholders may be able to control elections of directors, amendments of our organizational documents, or approval of any merger, sale of assets, or other major corporate transaction. This may prevent or discourage unsolicited acquisition proposals or offers for our common stock that you may feel are in your best interest as one of our stockholders.

~~Sales of a substantial number of shares of our common stock in the public market could cause our stock price to fall.~~

If our existing stockholders sell, or indicate an intention to sell, substantial amounts of our common stock in the public market after the lock-up and other legal restrictions on resale lapse, the trading price of our common stock could decline. Based upon the number of shares outstanding as of March 31, 2018, and after giving effect to the issuances of our Series C preferred stock in April 2018 and the closing of our initial public offering in May 2018, we had outstanding a total of approximately 42.3 million shares of common stock. Of these shares, approximately 5.0 million of the shares of our common stock sold in the IPO are freely tradable, without restriction, in the public market.

The lock-up agreements pertaining to our IPO will expire on October 29, 2018, following which up to an additional 38.3 million shares of common stock will be eligible for sale in the public market, of which approximately

13.5 million shares are held by current directors, executive officers and their respective affiliates and may be subject to Rule 144 under the Securities Act of 1933, as amended, or the Securities Act. The underwriters from our IPO may, however, in their sole discretion, permit our officers, directors and other stockholders who are subject to these lock-up agreements to sell or transfer shares prior to the expiration of the lock-up agreements.

~~If these additional shares of common stock are sold, or if it is perceived that they will be sold, in the public market, the trading price of our common stock could decline.~~

The holders of approximately 32.1 million shares of our common stock will be entitled to rights with respect to the registration of their shares under the Securities Act, subject to vesting schedules and to the lock-up agreements described above. Registration of these shares under the Securities Act would result in the shares becoming freely tradable without restriction under the Securities Act, except for shares purchased by affiliates. Any sales of securities by these stockholders could have a material adverse effect on the trading price of our common stock.

We incur increased costs as a result of operating as a public company, and our management devote substantial time to new compliance initiatives. We may fail to comply with the rules that apply to public companies, including Section 404 of the Sarbanes-Oxley Act of 2002, which could result in sanctions or other penalties that would harm our business.

We have incurred and will continue to incur significant legal, accounting and other expenses as a public company, including costs resulting from public company reporting obligations under the Exchange Act and regulations regarding corporate governance practices. The listing requirements of ~~The~~the Nasdaq Global Select Market and the rules of the Securities and Exchange Commission, or SEC, require that we satisfy certain corporate governance requirements relating to director independence, filing annual and interim reports, stockholder meetings, approvals and voting, soliciting proxies, conflicts of interest and a code of conduct. Our management and other personnel have devoted and will need to devote a substantial amount of time to ensure that we comply with all of these requirements. Moreover, the reporting requirements, rules and regulations will increase our legal and financial compliance costs and will make some activities more time-consuming and ~~costly.~~costlier. Any changes we make to comply with these obligations may not be sufficient to allow us to satisfy our obligations as a public company on a timely basis, or at all. These reporting requirements, rules and regulations, coupled with the increase in potential litigation exposure associated with being a public company, could also make it more difficult for us to attract and retain qualified persons to serve

on our board of directors or board committees or to serve as executive officers, or to obtain certain types of insurance, including directors’ and officers’ insurance, on acceptable terms.

We are subject to Section 404 of The Sarbanes-Oxley Act of 2002, or Section 404, and the related rules of the SEC, which generally require our management and independent registered public accounting firm to report on the effectiveness of our internal control over financial reporting. ~~Beginning with the second annual report that we will be required to file with the SEC,~~ Section 404 requires an annual management assessment of the effectiveness of our internal control over financial reporting. However, for so long as we remain an emerging growth company as defined in the JOBS Act, we intend to take advantage of certain exemptions from various reporting requirements that are applicable to public companies that are not emerging growth companies, including, but not limited to, not being required to comply with the auditor attestation requirements of Section 404. Once we are no longer an emerging growth company or, if prior to such date, we opt to no longer take advantage of the applicable exemption, we will be required to include an opinion from our independent registered public accounting firm on the effectiveness of our internal controls over financial reporting.

~~To date, we have never conducted a review of our internal control for the purpose of providing the reports required by these rules.~~ During the course of our review ~~and testing,~~of our internal controls we may identify deficiencies ~~and be unable to remediate them before~~in our internal controls that we must ~~provide the required reports.~~

~~Furthermore, if~~remediate. If we ~~have~~identify a material weakness in our internal controls over financial reporting, we may not detect errors on a timely basis and our financial statements may be materially misstated. We or our independent registered public accounting firm may not be able to conclude on an ongoing basis that we have effective internal control over financial reporting, which could harm our operating results, cause investors to lose confidence in our reported financial information and cause the trading price of our stock to fall. In addition, as a public company we will be required to file accurate and timely quarterly and annual reports with the SEC under the Exchange Act. In order to report our results of operations and financial statements on an accurate and timely basis, we will depend in part on CROs to provide timely and accurate notice of their costs to us. Any failure to report our financial results on an accurate and timely basis could result in sanctions, lawsuits, delisting of our shares from The Nasdaq Global Select Market or other adverse consequences that would materially harm to our business.

~~We have incurred substantial losses during our history and do not expect~~required to ~~become profitable~~record in the ~~near~~ future, ~~and we may never achieve profitability. To the extent that we continue to generate taxable losses, unused losses will carry forward to offset a portion of future taxable income,~~significant charges if ~~any, until such unused losses expire,~~our long-lived assets become impaired.

We test long-lived assets for impairment if ever. Under Sections 382 and 383 of the Internal Revenue Code of 1986, as amended, if a corporation undergoes an “ownership change,” generally defined as a greater than 50 percentage point change (by value) in its equity ownership by certain stockholders over a three-year period, the corporation’s ability to use its pre-change net operating loss carryforwards, or NOLs, and other pre-change tax attributes (such as research and development tax credits) to offset its post- change income or taxes may be limited. We may have experienced ownership changes in circumstances or the ~~past and~~occurrence of events suggest impairment exists. Any significant change in market conditions, including a sustained decline in our stock price, that indicate a reduction in carrying value may ~~experience ownership changes~~give rise to impairment in the ~~future~~period that indicators are present. For example, as a result of ~~our initial public offering and/or subsequent shifts~~the sustained decline in our stock ~~ownership (some~~price and related market capitalization and a general decline in equity values in the biotechnology industry, we performed an impairment assessment of long-lived assets in connection with the preparation of the condensed financial statements required to be included in this Quarterly Report on Form 10-Q. Based on this assessment, we recognized a non-cash long-lived asset impairment charge of $5.6 million during the three months ended September 30, 2023. See Note 8 to our condensed financial statements, “Commitments and Contingencies—Impairment of Operating Lease Right-of-Use Asset and Other Long-Lived Assets” for additional factors and assumption that can result in impairment charges on our long-lived assets.

It is possible that changes in circumstances, many of which ~~shifts~~ are outside of our ~~control).~~control, or in the numerous variables associated with the assumptions and estimates used in assessing the appropriate valuation of our long-lived assets, could in the future result in an impairment to our long-lived assets, requiring us to record impairment charges, which would adversely affect our business, financial condition and results of operations.

We are an “emerging growth company,” as defined in the JOBS Act, and we intend to take advantage of certain exemptions from various reporting requirements that are applicable to other public companies that are not emerging growth companies including, but not limited to, not being required to comply with the auditor attestation requirements of Section 404, reduced disclosure obligations regarding executive compensation in our periodic reports and proxy statements, and exemptions from the requirements of holding a nonbinding advisory vote on executive compensation and stockholder approval of any golden parachute payments not previously approved. In addition, as an “emerging growth company” the JOBS Act allows us to delay adoption of new or revised accounting pronouncements applicable to public companies until such pronouncements are made applicable to private companies. We have elected to use this extended transition period under the JOBS Act. As a result, ~~if we earn net taxable income,~~ our ~~ability to use our pre-change NOLs to offset such taxable income could~~financial statements may

not be subject to limitations. Similar provisions of state tax law may also apply. As a result, even if we attain profitability, we may be unable to use a material portion of our NOLs and other tax attributes.

~~Additionally, the Tax Act, which was enacted on December 22, 2017, significantly reforms the Code, including changes~~comparable to the rules governing net operating loss carryforwards. For net operating loss carryforwards arising in tax years beginning after December 31, 2017, the Tax Act limits a taxpayer’s ability to utilize such carryforwards to 80%financial statements of taxable income. In addition, net operating loss carryforwards arising in tax years ending after December 31, 2017 can be carried forward indefinitely, but carryback is generally prohibited. Net operating loss carryforwards generated by us before

January 1, 2018 will not be subject to the taxable income limitation and will continue to have a twenty- year carryforward period. However, the changes in the carryforward and carryback periods as well as the new limitation on use of net operating losses may significantly impact our ability to use net operating loss carryforwards generated after December 31, 2017, as well as the timing of any such use, and could adversely affect our results of operations.

~~Provisions in our charter documents and under Delaware law could discourage a takeover that stockholders may consider favorable and may lead to entrenchment of management.~~

We are also subject to the anti-takeover provisions contained in Section 203 of the Delaware General Corporation Law. Under Section 203, a corporation may not, in general, engage in a business combination with any holder of 15% or more of its capital stock unless the holder has held the stock for three years or, among other exceptions, the board of directors has approved the transaction.

~~Claims for indemnification by our directors and officers may reduce our available funds to satisfy successful third-party claims against us and may reduce the amount of money available to us.~~

In addition, as permitted by Section 145 of the Delaware General Corporation Law, our amended and restated bylaws to be effective immediately prior to the completion of the offering and our indemnification agreements that we have entered into with our directors and officers will provide that:

~~We do not currently intend to pay dividends on~~be a less active trading market for our common stock and ~~consequently, your ability~~our stock price may be more volatile. We may take advantage of these reporting exemptions until we are no longer an emerging growth company. Even after we no longer qualify as an emerging growth company, we may still qualify as a “smaller reporting company” which may allow us to ~~achieve a return on your investment~~take advantage of many of the same exemptions from disclosure requirements including not being required to comply with the auditor attestation requirements of Section 404(b) of the Sarbanes-Oxley Act. We will ~~depend on appreciation in~~remain an emerging growth company until the ~~price~~earlier of (1) the last day of the year following the fifth anniversary of the consummation of our ~~common stock.~~

~~We do not currently intend~~IPO, (2) the last day of the year in which we have total annual gross revenue of at least $1.235 billion, (3) the last day of the year in which we are deemed to ~~pay any cash dividends on our common stock for~~be a “large accelerated filer” as defined in Rule 12b-2 under the ~~foreseeable future. We currently intend to invest our future earnings,~~Exchange Act, which would occur if any, to fund our growth. Therefore, you are not likely to receive any dividends on your common stock for the foreseeable future. Since we do not intend to pay dividends, your ability to receive a return on your investment will depend on any future appreciation in the market value of our common ~~stock. There is~~stock held by non-affiliates exceeded $700.0 million as of the last business day of the second fiscal quarter of such year or (4) the date on which we have issued more than $1.0 billion in non-convertible debt securities during the prior three-year period. We expect that we will no ~~guarantee that our common stock will appreciate or even maintain the price~~longer qualify as an emerging growth company after December 31, 2023, at which time we will become subject to certain disclosure and compliance requirements as discussed herein that apply to other public companies but that did not previously, or currently, apply to us due to our ~~holders have purchased it.~~status as an emerging growth company.

There were no sales of unregistered securities during the nine months ended September 30, 2023.

Repurchase of Shares or of Company Equity Securities

~~During the quarter ended March 31, 2018, we issued and sold the following unregistered securities:~~

We issued an aggregate of 3,590,573 shares of our Series C Preferred Stock at a price per share of $15.3317, for a total amount raised (including the cancellation of indebtedness) of approximately $55.0 million.

We granted stock options under our 2013 Equity Incentive Plan, as amended, covering an aggregate of 493,776 shares of common stock at a weighted average exercise price of $5.79. Of these, none of the options were cancelled without being exercised.

We sold an aggregate of 400,587 shares of common stock to employees and consultants for cash consideration and or promissory notes in the aggregate amount of $1.2 million upon the exercise of stock options.

~~Use of Proceeds from our Initial Public Offering of Common Stock~~None.

On May 2, 2018, the U.S. Securities and Exchange Commission declared effective our registration statement on Form S-1 (File No. 333-224163), as amended, filed in connection with our initial public offering (IPO). The IPO closed on May 7, 2018 and we issued and sold 5,000,000 shares of our common stock at a price to the public of $17.00 per share. We received gross proceeds from the IPO of approximately $76.1 million, before deducting underwriting discounts and commissions, and estimated offering expenses payable by us. The managing underwriters of the offering were Goldman Sachs & Co. LLC, Morgan Stanley & Co. LLC, Citigroup Global Markets, Inc. and Mizuho Securities USA LLC. No offering expenses were paid or are payable, directly or indirectly, to our directors or officers, to persons owning 10% or more of any class of our equity securities or to any of our affiliates.

The net proceeds from the IPO have been invested in interest-bearing, investment-grade instruments and government securities. There has been no material change in the expected use of the net proceeds from our IPO as described in our registration statement on Form S-1. Repurchase of Shares or Company Equity Securities

~~None.~~

Item 3. Default Upon Senior Securities

None.

Item 4. Mine Safety Disclosures

Not ~~applicable~~applicable.

Item 5. Other Information

None.

Item ~~6.Exhibits~~

Exhibit

Exhibit Description

Incorporated by Reference

Filed
Herewith
Number

Form

Date

Number

3.1

Amended and Restated Certificate of Incorporation.

8-K

5-7-2018

3.1

3.2

Amended and Restated Bylaws, currently in effect.

8-K

5-7-2017

3.2

4.1

Reference is made to exhibits 3.1 through 3.2.

4.2

Form of Common Stock Certificate.

S-1/A

4-23-2018

4.2

4.3

Amended and Restated Investors’ Rights Agreement, dated March 15, 2018, by and among Unity Biotechnology, Inc. and the investors party thereto.

S-1

4-5-2018

4.3

10.1(a)#

2018 Incentive Award Plan.

S-8

5-7-2018

99.2(A)

10.1(b)#

Form of Stock Option Grant Notice and Stock Option Agreement under the 2018 Incentive Award Plan.

S-1

4-5-2018

10.4
(b)

10.1(c)#

Form of Restricted Stock Award Grant Notice under the 2018 Incentive Award Plan.

S-1

4-5-2018

10.4
(c)

10.1(d)#

Form of Restricted Stock Unit Award Grant Notice under the 2017 Incentive Award Plan.

S-1

4-5-2018

10.4
(d)

10.2#

2018 Employee Stock Purchase Plan.

S-8

5-7-2018

99.3

10.3#

Non-Employee Director Compensation Program.

S-1

4-5-2018

10.6

10.4#

Form of Indemnification Agreement for directors and officers.

S-1

4-5-2018

10.7

~~10.5#~~	~~Employment Agreement, dated January 29, 2018, by and between Unity Biotechnology, Inc. and Keith R. Leonard Jr~~.	~~S-1~~	~~4-5-2018~~	~~10.8~~

~~10.6#~~	~~Employment Agreement, dated January 29, 2018, by and between Unity Biotechnology, Inc. and Nathaniel E. David.~~	~~S-1~~	~~4-5-2018~~	~~10.9~~

~~10.7#~~	~~Employment Agreement, dated January 29, 2018, by and between Unity Biotechnology, Inc. and Robert C. Goeltz II.~~	~~S-1~~	~~4-5-2018~~	~~10.10~~

~~10.8#~~	~~Employment Agreement, dated January 29, 2018, by and between Unity Biotechnology, Inc. and Jamie Dananberg.~~	~~S-1~~	~~4-5-2018~~	~~10.11~~

~~10.9#~~	~~Employment Agreement, dated January 29, 2018, by and between Unity Biotechnology, Inc. and Daniel G. Marquess.~~	~~S-1~~	~~4-5-2018~~	~~10.12~~

~~10.10#~~	~~Employment Agreement, dated January 29, 2018, by and between Unity Biotechnology, Inc. and Tamara L. Tompkins.~~	~~S-1~~	~~4-5-2018~~	~~10.13~~

~~31.1~~	~~Certification of Chief Executive Officer of Unity Biotechnology, Inc., as required by Rule 13a-14(a) or Rule 15d-14(a).~~				X

~~31.2~~	~~Certification of Chief Financial Officer of Unity Biotechnology, Inc., as required by Rule 13a-14(a) or Rule 15d-14(a).~~				X

32.1*	Certification by the Chief Executive Officer and Chief Financial Officer, as required by Rule 13a-14(b) or Rule 15d-14(b) and Section 1350 of Chapter 36 of Title 18 of the United States Code (18 U.S.C. §1350).				X

~~101.INS~~	~~XBRL Instance Document~~				X

~~101.SCH~~	~~XBRL Taxonomy Extension Schema Document~~				X

~~101.CAL~~	~~XBRL Taxonomy Extension Calculation Linkbase Document~~				X

~~101.DEF~~	~~XBRL Taxonomy Extension Definition Linkbase Document~~				X

~~101.LAB~~	~~XBRL Taxonomy Extension Labels Linkbase Document~~				X

~~101.PRE~~	~~XBRL Taxonomy Extension Presentation Linkbase Document~~				X

#	~~Indicates management contract or compensatory plan.~~

The certification attached as Exhibit 32.1 that accompanies this Quarterly Report on Form 10-Q is not deemed filed with the SEC and is not to be incorporated by reference into any filing of Unity Biotechnology, Inc. under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended, whether made before or after the date of this Form 10-Q, irrespective of any general incorporation language contained in such filing.

~~SIGNATURES~~6. Exhibits


Exhibit	Exhibit Description	Incorporated by Reference			Filed
Number		Form	Date	Number	Herewith

3.1	Amended and Restated Certificate of Incorporation of Unity Biotechnology, Inc.	8-K	5/7/2018	3.1

3.2	Certificate of Amendment to Amended and Restated Certificate of Incorporation of Unity Biotechnology, Inc.	8-K	10/19/2022	3.1

3.3	Amended and Restated Bylaws of Unity Biotechnology, Inc.	8-K	5/7/2018	3.2

4.1	Reference is made to exhibits 3.1 through 3.3.

4.2	Form of Common Stock Certificate.	10-Q	11/8/2022	4.2

4.3	Form of Warrant.	8-K	8/22/2022	4.1

4.4	Amended and Restated Investors’ Rights Agreement, dated as of March 15, 2018 by and among Unity Biotechnology, Inc. and the investors party thereto.	S-1	4/5/2018	4.3

31.1	Certification of Principal Executive Officer Pursuant to Rules 13a-14(a) and 15d-14(a) under the Securities Exchange Act of 1934, as Adopted Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.				X

31.2	Certification of Principal Financial Officer Pursuant to Rules 13a-14(a) and 15d-14(a) under the Securities Exchange Act of 1934, as Adopted Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.				X

32.1*	Certification by the Principal Executive Officer and Principal Financial Officer Pursuant to 18 U.S.C. Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.				X

101.INS	Inline XBRL Instance Document				X

101.SCH	Inline XBRL Taxonomy Extension Schema Document				X

101.CAL	Inline XBRL Taxonomy Extension Calculation Linkbase Document				X

101.DEF	Inline XBRL Taxonomy Extension Definition Linkbase Document				X

101.LAB	Inline XBRL Taxonomy Extension Label Linkbase Document				X

101.PRE	Inline XBRL Taxonomy Extension Presentation Linkbase Document				X

104	The cover page from the Company’s Quarterly Report on Form 10-Q for the three months ended September 30, 2023, has been formatted in Inline XBRL.				X

# Indicates management contract or compensatory plan.

* The certification attached as Exhibit 32.1 that accompanies this Quarterly Report on Form 10-Q is not deemed filed with the SEC and is not to be incorporated by reference into any filing of Unity Biotechnology, Inc. under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended, whether made before or after the date of this Quarterly report on Form 10-Q, irrespective of any general incorporation language contained in such filing.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.


			Unity Biotechnology, Inc.

Date: ~~June 7, 2018~~November 13, 2023	By:	~~By: /s/ Keith R. Leonard Jr.~~/s/ Anirvan Ghosh
	Anirvan Ghosh, Ph.D. ~~Keith R. Leonard Jr.~~ ~~Chairman and~~ Chief Executive Officer (Principal Executive Officer)
Date: November 13, 2023	By:	/s/ Lynne Sullivan


~~Date: June 7, 2018~~			~~By: /s/ Robert C. Goeltz II~~Lynne Sullivan ~~Robert C. Goeltz II~~ Chief Financial Officer (Principal Financial and Accounting Officer)


Delaware	26-4726035
(State or other jurisdiction of incorporation or organization)	(I.R.S. Employer Identification No.)
~~3280 Bayshore Blvd. Suite 100~~ ~~Brisbane, CA~~	~~94005~~
285 East Grand Ave. South San Francisco, CA	94080
(Address of principal executive offices)	(Zip Code)


Title of each class	Trading Symbol(s)	Name of each exchange on which registered
Common Stock, par value $0.0001	UBX	The Nasdaq Global Select Market


PART II. FINANCIAL INFORMATION

Item 1	Condensed Financial Statements	2
	Condensed Balance Sheets as of ~~March 31, 2018(unaudited)~~September 30, 2023 (unaudited) and December 31, ~~2017~~2022	2
	Condensed ~~Statement~~Statements of Operations and Comprehensive Loss for the Three and Nine Months Ended ~~March 31, 2018~~September 30, 2023 and ~~2017~~2022 (unaudited)	3
	Condensed ~~Statement~~Statements of Stockholders’ Equity for the Three and Nine Months Ended September 30, 2023 and 2022 (unaudited)	4
	Condensed Statements of Cash Flows for the ~~Three~~ NineMonths Ended ~~March 31, 2018~~September 30, 2023 and ~~2017~~2022 (unaudited)	46
	Notes to Condensed Financial Statements (unaudited)	57
Item 2	Management’s Discussion and Analysis of Financial Condition and Results of Operations	2022
Item 3	Quantitative and Qualitative Disclosures About Market Risk	2634
Item 4	Controls and Procedures	2634

PART ~~II –~~II. OTHER INFORMATION

Item 1	Legal Proceedings	2635
Item 1A	Risk Factors	2635
Item 2	Unregistered Sales of Equity Securities and Use of Proceeds	7080
Item 3	Default Upon Senior Securities	7180
Item 4	Mine Safety Disclosures	7180
Item 5	Other Information	7180
~~Items~~Item 6	Exhibits	7181
Signatures		7382


	September 30, 2023			December 31, 2022(1)
	(Unaudited)
Assets
Current assets:
Cash and cash equivalents	$	7,876		$	12,736
Short-term marketable securities		38,063			82,059
Prepaid expenses and other current assets		3,599			1,740
Total current assets		49,538			96,535
Property and equipment, net		5,314			7,825
Operating lease right-of-use assets		13,522			19,042
Long-term restricted cash		896			896
Other long-term assets		—			52
Total assets	$	69,270		$	124,350
Liabilities and Stockholders’ Equity
Current liabilities:
Accounts payable	$	1,149		$	1,790
Accrued compensation		2,226			3,020
Accrued and other current liabilities		5,258			5,334
Current portion of long-term debt		—			9,476
Total current liabilities		8,633			19,620
Operating lease liability, net of current portion		24,431			26,991
Long-term debt, net of current portion		—			10,891
Total liabilities		33,064			57,502
Commitments and contingencies (Note 8)
Stockholders’ equity:
Convertible preferred stock, $0.0001 par value; 10,000,000 shares authorized; no shares issued and outstanding		—			—
Common stock, $0.0001 par value; 300,000,000 shares authorized as of September 30, 2023 and December 31, 2022; 14,614,890 and 14,215,302 shares issued and outstanding as of September 30, 2023 and December 31, 2022, respectively(2)		1			1
Additional paid-in capital		534,570			527,049
Accumulated other comprehensive loss		(55	)		(251	)
Accumulated deficit		(498,310	)		(459,951	)
Total stockholders’ equity		36,206			66,848
Total liabilities and stockholders’ equity	$	69,270		$	124,350


	September 30, 2023		December 31, 2022
Prepaid research and development expenses	$	328	$	378
Prepaid insurance expenses		931		710
Tax credit receivable		1,493		—
Interest receivable		218		235
Other prepaid expenses and current assets		629		417
Total prepaid expenses & other current assets	$	3,599	$	1,740

	March 31, 2018			December 31, 2017
	(Unaudited)
Assets
Current assets:
Cash and cash equivalents	$	62,754		$	7,298
Contribution receivable		—			1,382
Short-term marketable securities		71,281			79,212
Deferred offering costs		1,707			—
Prepaid expenses and other current assets		697			988
Total current assets		136,439			88,880
Property and equipment, net		6,591			6,958
Long-term marketable securities		—			5,118
Restricted cash		550			550
Other long-term assets		522			518
Total assets	$	144,102		$	102,024
Liabilities, Convertible Preferred Stock, and Stockholders’ (Deficit) Equity
Current liabilities:
Accounts payable	$	5,037		$	2,378
Accrued compensation		958			2,181
Accrued and other current liabilities		4,668			3,338
Total current liabilities		10,663			7,897
Deferred rent, net of current portion		3,062			3,166
Other non-current liabilities		101			118
Total liabilities		13,826			11,181
Commitments and contingencies (Note 6)
Convertible preferred stock, $0.0001 par value; 103,283,818 and 91,739,149 shares authorized as of March 31, 2018 and December 31, 2017, respectively; 31,750,297 and 28,159,724 shares issued and outstanding as of March 31, 2018 and December 31, 2017, respectively; aggregate liquidation preference of $245,825 as of March 31, 2018 and $190,825 as of December 31, 2017, respectively		228,907			173,956
Stockholders’ deficit:
Common stock, $0.0001 par value; 140,000,000 and 122,000,000 shares authorized as of March 31, 2018 and December 31, 2017, respectively; 5,230,976 and 4,830,389 shares issued and outstanding as of March 31, 2018 and December 31, 2017, respectively		1			1
Additional paid-in capital		5,511			4,072
Related party promissory notes for purchase of common stock		(592	)		(202	)
Employee promissory notes for purchase of common stock		(400	)		—
Accumulated other comprehensive loss		(138	)		(104	)
Accumulated deficit		(103,013	)		(86,880	)
Total stockholders’ deficit		(98,631	)		(83,113	)
Total liabilities, convertible preferred stock, and stockholders’ deficit	$	144,102		$	102,024


	Common Stock				Additional Paid-In			Accumulated Other Comprehensive			Accumulated			Total Stockholders’
	Shares		Amount		Capital			Gain (Loss)			Deficit			Equity
Balances at December 31, 2022		14,215,302	$	1	$	527,049		$	(251	)	$	(459,951	)	$	66,848
Issuance of common stock, net of issuance costs, under at-the-market (“ATM”) offering program		106,781		—		274			—			—			274
Vesting of restricted stock units		37,131		—		—			—			—			—
Stock-based compensation		—		—		2,270			—			—			2,270
Unrealized gain on available-for-sale marketable securities		—		—		—			101			—			101
Net loss		—		—		—			—			(10,865	)		(10,865	)
Balances at March 31, 2023		14,359,214	$	1	$	529,593		$	(150	)	$	(470,816	)	$	58,628
Issuance of common stock, net of issuance costs, under ATM offering program		168,000		—		518			—			—			518
Issuance of common stock under 2018 ESPP		41,497		—		91			—			—			91
Vesting of restricted stock units		26,766		—		—			—			—			—
Stock-based compensation		—		—		2,361			—			—			2,361
Unrealized gain on available-for-sale marketable securities		—		—		—			14			—			14
Net loss		—		—		—			—			(12,205	)		(12,205	)
Balances at June 30, 2023		14,595,477	$	1	$	532,563		$	(136	)	$	(483,021	)	$	49,407
Fees related to the ATM offering program		—		—		(48	)		—			—			(48	)
Vesting of restricted stock units		19,413		—		—			—			—			—
Stock-based compensation		—		—		2,055			—			—			2,055
Unrealized gain on available-for-sale marketable securities		—		—		—			81			—			81
Net loss		—		—		—			—			(15,289	)		(15,289	)
Balances at September 30, 2023		14,614,890	$	1	$	534,570		$	(55	)	$	(498,310	)	$	36,206


	Common Stock(1)				Additional Paid-In		Accumulated Other Comprehensive			Accumulated			Total Stockholders’
	Shares		Amount		Capital		(Loss)			Deficit			Equity
Balances at December 31, 2021		6,299,158	$	1	$	459,636	$	(44	)	$	(400,024	)	$	59,569
Issuance of common stock, net of issuance costs, under ATM offering program		232,500		—		3,420		—			—			3,420
Issuance of common stock to Lincoln Park Capital Fund		90,000		—		910		—			—			910
Issuance of common stock to Hercules Capital		262,761		—		3,179		—			—			3,179
Vesting of restricted stock units		30,358		—		—		—			—			—
Stock-based compensation		—		—		2,660		—			—			2,660
Unrealized loss on available-for-sale marketable securities		—		—		—		(132	)		—			(132	)
Net loss		—		—		—		—			(18,915	)		(18,915	)
Balances at March 31, 2022		6,914,777	$	1	$	469,805	$	(176	)	$	(418,939	)	$	50,691
Issuance of common stock, net of issuance costs, under ATM offering program		—		—		13		—			—			13
Issuance of common stock under 2018 ESPP		18,202		—		125		—			—			125
Vesting of restricted stock units		25,481		—		—		—			—			—
Stock-based compensation		—		—		2,250		—			—			2,250
Unrealized loss on available-for-sale marketable securities		—		—		—		(11	)		—			(11	)
Net loss		—		—		—		—			(13,137	)		(13,137	)
Balances at June 30, 2022		6,958,460	$	1	$	472,193	$	(187	)	$	(432,076	)	$	39,931
Issuance of common stock, net of issuance costs, under ATM offering program		633,464		—		8,570		—			—			8,570
Sale of common stock and warrants to purchase common shares under follow-on offering, net of issuance costs		6,428,571		—		41,650		—			—			41,650
Vesting of restricted stock units		15,720		—		—		—			—			—
Stock-based compensation		—		—		2,210		—			—			2,210
Unrealized loss on available-for-sale marketable securities		—		—		—		(88	)		—			(88	)
Net loss		—		—		—		—			(13,708	)		(13,708	)
Balances at September 30, 2022		14,036,215	$	1	$	524,623	$	(275	)	$	(445,784	)	$	78,565

	Three Months Ended March 31
	2018			2017
Operating expenses:
Research and development	$	13,025		$	6,970
General and administrative		3,457			2,070
Total operating expenses		16,482			9,040
Loss from operations		(16,482	)		(9,040	)
Interest income		352			108
Other expense, net		(3	)		(2	)
Net loss		(16,133	)		(8,934	)
Other comprehensive loss
Unrealized loss on marketable securities, net of tax		(34	)		—
Comprehensive loss	$	(16,167	)	$	(8,934	)
Net loss per share, basic and diluted	$	(4.69	)	$	(2.90	)
Weighted average number of shares used in computing net loss per share, basic and diluted		3,437,345			3,079,551

	March 31,		December 31,
	2018		2017
	(in thousands)
Cash and cash equivalents	$	62,754	$	7,298
Restricted cash	550		550
Total cash, cash equivalents, and restricted cash	$	63,304	$	7,848

	March 31, 2018
	Total		Level 1		Level 2		Level 3
	(in thousands)
Money market funds	$	62,085	$	62,085	$	—	$	—
Total	$	62,085	$	62,085	$	—	$	—
Short-term marketable securities:
Commercial paper		5,428		—		5,428		—
Corporate debt securities		10,140		—		10,140		—
Asset-backed securities		14,404		—		14,404		—
U.S. government debt securities		41,309		—		41,309		—
Total short-term marketable securities		71,281		—		71,281		—
Total	$	133,366	$	62,085	$	71,281	$	—

	December 31, 2017
	Total		Level 1		Level 2		Level 3
	(in thousands)
Money market funds	$	5,709	$	5,709	$	—	$	—
Total	$	5,709	$	5,709	$	—	$	—
Short-term marketable securities:
Commercial paper		6,359		—		6,359		—
Corporate debt securities		16,149		—		16,149		—
Asset-backed securities		14,588		—		14,588		—
U.S. government debt securities		42,116		—		42,116		—
Long-term marketable securities:
Asset-backed securities		2,742		—		2,742		—
U.S. government debt securities		2,376		—		2,376		—
Total marketable securities		84,330		—		84,330		—
Total	$	90,039	$	5,709	$	84,330	$	—


	Amount
	(in thousands)
2018 (remaining 9 months)	$	1,473
2019		2,012
2020		2,072
2021		2,135
2022		1,621
Total future minimum lease payments	$	9,313

	At March 31, 2018
	Shares Authorized		Shares Issued and Outstanding		Liquidation Preference		Carrying Value
	(in thousands, except for share amounts)
Series A-1		9,085,738		2,887,086	$	2,495	$	2,457
Series A-2		32,653,411		10,498,269		9,198		9,214
Series B		50,000,000		14,774,369		179,132		162,285
Series C		11,544,669		3,590,573		55,000		54,951
Total convertible preferred stock		103,283,818		31,750,297	$	245,825	$	228,907

	At December 31, 2017
	Shares Authorized		Shares Issued and Outstanding		Liquidation Preference		Carrying Value
	(in thousands, except for share amounts)
Series A-1		9,085,738		2,887,086	$	2,495	$	2,457
Series A-2		32,653,411		10,498,269		9,198		9,214
Series B		50,000,000		14,774,369		179,132		162,285
Total convertible preferred stock		91,739,149		28,159,724	$	190,825	$	173,956


	Number of Shares			Weighted- Average Exercise Price
Balances at December 31, 2022		1,609,938		$	27.51
Granted		421,600		$	2.85
Canceled		(28,155	)	$	18.14
Balances at September 30, 2023		2,003,383		$	13.88

	Number of Shares			Weighted- Average Exercise Price
Balances at December 31, 2017		4,196,203			3.06
Granted		493,776			5.79
Exercised		(400,587	)		3.10
Canceled		(25,423	)		3.39
Balances at March 31, 2018		4,263,969			3.37


	Number of Shares			Weighted- Average Grant Date Fair Value
Unvested at December 31, 2022		146,333		$	27.66
Granted		—		$	—
Vested		(83,310	)	$	30.07
Canceled		(3,658	)	$	4.76
Unvested at September 30, 2023		59,365		$	25.65

	Shares			Weighted Average Grant Date Fair Value
Unvested at December 31, 2017		478,971		$	4.57
Granted		—		$	4.57
Vested		(119,742	)	$	4.57
Unvested at March 31, 2018		359,229		$	4.57