CalciMedica (CALC) 10-K 10 Mar 22 2021 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2021	Mar. 04, 2022	Jun. 30, 2021
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Trading Symbol	GRAY
Entity Registrant Name	GRAYBUG VISION, INC.
Entity Central Index Key	0001534133
Entity Current Reporting Status	Yes
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Shell Company	false
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Common Stock, Shares Outstanding		21,357,773
Entity File Number	001-39538
Entity Tax Identification Number	45-2120079
Entity Address, Address Line One	203 Redwood Shores Parkway
Entity Address, Address Line Two	Suite 620
Entity Address, City or Town	Redwood City
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94065
City Area Code	650
Local Phone Number	487-2800
Entity Interactive Data Current	Yes
Title of 12(b) Security	Common Stock, par value $0.0001 per share
Security Exchange Name	NASDAQ
Entity Incorporation, State or Country Code	DE
Document Annual Report	true
Document Transition Report	false
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Public Float			$ 57,700,000
ICFR Auditor Attestation Flag	false
Auditor Firm ID	42
Auditor Name	Ernst & Young LLP
Auditor Location	Redwood City, California
Documents Incorporated by Reference	Portions of the registrant’s Definitive Proxy Statement relating to the 2022 Annual Meeting of Shareholders are incorporated by reference into Part III of this Annual Report on Form 10-K to the extent stated herein. The Definitive Proxy Statement will be filed within 120 days of the Registrant’s fiscal year ended December 31, 2021. Except with respect to information specifically incorporated by reference in this Form 10-K, the Proxy Statement is not deemed to be filed as part of this Form 10-K .

Balance Sheets (Unaudited)

Balance Sheets (Unaudited) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 13,364	$ 33,418
Short-term investments	50,306	61,615
Prepaid expenses and other current assets	3,408	4,207
Total current assets	67,078	99,240
Property and equipment, net	1,981	1,946
Prepaid expenses and other non-current assets	29	608
Total assets	69,088	101,794
Current liabilities:
Accounts payable	527	2,513
Accrued research and development	304	1,356
Other current liabilities	3,226	3,128
Total current liabilities	4,057	6,997
Deferred rent, long term portion	8	11
Total liabilities	4,065	7,008
Commitments and contingencies (Note 5)
Stockholders’ Equity:
Preferred stock, $0.0001 par value; 10,000,000 authorized, no shares outstanding as of December 31, 2021 and 2020, respectively
Common stock, $0.0001 par value; 500,000,000 shares authorized, 21,357,773 and 20,979,265 shares issued and outstanding as of December 31, 2021 and 2020, respectively	2	2
Additional paid-in capital	234,225	228,155
Accumulated deficit	(169,188)	(133,367)
Accumulated other comprehensive loss	(16)	(4)
Total stockholders’ equity	65,023	94,786
Total liabilities and stockholders’ equity	$ 69,088	$ 101,794

Balance Sheets (Unaudited) (Par

Balance Sheets (Unaudited) (Parenthetical) - $ / shares	Dec. 31, 2021	Dec. 31, 2020
Statement Of Financial Position [Abstract]
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	21,357,773	20,979,265
Common stock, shares outstanding	21,357,773	20,979,265

Statements of Operations

Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Operating expenses:
Research and development	$ 18,903	$ 20,962
General and administrative	17,044	8,870
Total operating expenses	35,947	29,832
Loss from operations	(35,947)	(29,832)
Interest income	126	143
Change in fair value of preferred stock tranche obligation		2,158
Net loss	(35,821)	(27,531)
Cumulative dividends on convertible preferred stock		(7,189)
Net loss attributable to common stockholders	$ (35,821)	$ (34,720)
Net loss per common share—basic and diluted	$ (1.69)	$ (5.25)
Weighted-average number of shares outstanding used in computing net loss per common share—basic and diluted	21,199,291	6,618,445

Statements of Comprehensive Los

Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Income Statement [Abstract]
Net loss	$ (35,821)	$ (27,531)
Unrealized loss on available-for-sale securities, net of tax	(12)	(7)
Comprehensive loss	$ (35,833)	$ (27,538)

Statements of Convertible Prefe

Statements of Convertible Preferred Stock and Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Initial Public Offering	Common Stock	Common StockInitial Public Offering	Additional Paid-In Capital	Additional Paid-In CapitalInitial Public Offering	Accumulated Deficit	Accumulated Other Comprehensive Income (loss)	Convertible Preferred Stock	Convertible Preferred StockInitial Public Offering
Beginning Balance at Dec. 31, 2019	$ (102,954)				$ 2,879		$ (105,836)	$ 3
Temporary Equity, Beginning Balance, Shares at Dec. 31, 2019	117,809,883								117,809,883
Temporary Equity, Beginning Balance at Dec. 31, 2019	$ 131,363								$ 131,363
Beginning Balance, Shares at Dec. 31, 2019			1,371,467
Issuance of common stock upon the initial public offering, net		$ 92,050		$ 1		$ 92,049
Issuance of common stock upon initial public offering, net of issuance costs, Shares				6,468,750
Conversion of convertible preferred stock into common stock upon the initial public offering		$ 131,363		$ 1		$ 131,362
Temporary Equity, Conversion of convertible preferred stock into common stock upon initial public offering, Shares										(117,809,883)
Temporary Equity, Conversion of convertible preferred stock into common stock upon initial public offering										$ (131,363)
Conversion of convertible preferred stock into common stock upon the initial public offering, Shares				13,085,913
Stock issued on exercise of stock options	77				77
Stock issued on exercise of stock options, Shares			53,135
Stock-based compensation expense	1,788				1,788
Net loss	(27,531)						(27,531)
Unrealized loss on available-for-sale securities, net of tax	(7)							(7)
Ending Balance at Dec. 31, 2020	94,786		$ 2		228,155		(133,367)	(4)
Ending Balance, Shares at Dec. 31, 2020			20,979,265
Stock issued on exercise of stock options	$ 695				695
Stock issued on exercise of stock options, Shares	353,508		353,508
Issuance of common stock upon vesting of restricted stock units, Shares			25,000
Stock-based compensation expense	$ 5,375				5,375
Net loss	(35,821)						(35,821)
Unrealized loss on available-for-sale securities, net of tax	(12)							(12)
Ending Balance at Dec. 31, 2021	$ 65,023		$ 2		$ 234,225		$ (169,188)	$ (16)
Ending Balance, Shares at Dec. 31, 2021			21,357,773

Statement of Cash Flows

Statement of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Operating activities:
Net loss	$ (35,821)	$ (27,531)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	5,375	1,788
Depreciation	519	395
Change in fair value of preferred stock tranche obligation		(2,158)
Accretion of premium and discounts on short-term investments	58	1
Changes in operating assets and liabilities:
Prepaid expenses and other current and non-current assets	1,378	(2,400)
Accounts payable	(2,052)	(1,462)
Accrued research and development	(1,052)	(977)
Other current and non-current liabilities	95	280
Net cash used in operating activities	(31,500)	(32,064)
Investing activities:
Purchases of property and equipment	(488)	(1,023)
Purchases of investments	(94,570)	(61,637)
Maturity of investments	105,809	20,100
Net cash provided by (used in) investing activities	10,751	(42,560)
Financing activities:
Proceeds from issuance of common stock upon initial public offering, net of underwriting discounts and commissions		96,255
Proceeds from exercise of stock options	695	77
Payment of offering costs		(4,160)
Net cash provided by financing activities	695	92,172
Net (decrease) increase in cash and cash equivalents	(20,054)	17,548
Cash and cash equivalents at beginning of period	33,418	15,870
Cash and cash equivalents at end of period	13,364	33,418
Supplemental disclosure of noncash items:
Conversion of convertible preferred stock into common stock upon initial public offering		131,363
Property and equipment purchases included in accounts payable	$ 115	$ 49

Organization

Organization	12 Months Ended
	Dec. 31, 2021
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Organization	1. Organization Graybug Vision, Inc., the Company or Graybug, is a clinical-stage biopharmaceutical company developing medicines for the treatment of diseases of the retina and optic nerve. The Company presently devotes substantially all of its resources to conducting research and development and raising capital. The Company was founded in May 2011 and maintains facilities in Redwood City, California and Baltimore, Maryland. The Company is subject to risks common to clinical stage companies in the biopharmaceutical industry, including dependence on the clinical success of its product candidates, ability to obtain regulatory approvals of its product candidates, compliance with regulatory requirements, the need for substantial additional financing and protection of its proprietary technology. Going Concern Considerations The Company incurred losses from operations and had negative cash flows from operating activities for the years ended December 31, 2021, and 2020, and the Company’s accumulated deficit at December 31, 2021 is $169.2 million. The Company’s current operating plan indicates it will continue to incur losses from operations and generate negative cash flows from operating activities, given ongoing expenditures related to extensive research and development and the Company’s lack of revenue-generating activities at this point in the Company’s life cycle. Even if the Company’s product development efforts are successful, it is uncertain when, if ever, the Company will realize significant revenue from product sales. In March 2021, the Company decided not to proceed with the significant investment required to initiate two Phase 3 clinical trials for GB-102 in late 2021. As a result, management continues to believe that the Company’s current cash, cash equivalents and short-term investments are adequate to meet its cash needs for at least 12 months from the issuance date of this Form 10-K. The Company will seek to raise additional funds in order to further advance its research and development programs other than GB-102, operate its business, secure research and development collaborations, and meet its obligations as they come due. The Company is pursuing financing alternatives, similar to what the Company has previously executed, which include debt and equity financing. Such sources of capital may not, however, be available to the Company in the necessary time frame, in the amounts that the Company requires, on terms that are acceptable to the Company, or at all. If the Company is unable to raise the necessary funds when needed or reduce spending on currently planned activities, it may not be able to continue the development of its products or the Company could be required to delay, scale back, or eliminate some or all of its research and development programs and other operations, which may materially harm its business, financial position and results of operations. COVID-19 Pandemic The impact of the worldwide spread of a novel strain of coronavirus (“COVID-19”) has been unprecedented and unpredictable,

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Basis of Presentation The accompanying financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America, or GAAP, and stated in U.S. dollars. Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification, or ASC, and Accounting Standards Updates, or ASUs, of the Financial Accounting Standards Board, or FASB. Use of Estimates The preparation of financial statements in conformity with GAAP requires the Company to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statements and reported amounts of expenses during the reporting periods. Actual results could differ from those estimates. On an ongoing basis, the Company evaluates its estimates, including those related to accrued research and development expenses, contingent milestone payments, other long-lived assets, stock-based compensation , and the valuation of deferred tax assets . The Company bases its estimates using historical experience, Company forecasts and future plans, current economic conditions, and information from third-party professionals that management believes to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets and liabilities and recorded amounts of expenses that are not readily apparent from other sources , and adjusts those estimates and assumptions when facts and circumstances dictate. The Company’s results can also be affected by economic, political, legislative, regulatory and legal actions. Economic conditions, such as recessionary trends, inflation, interest, changes in regulatory laws and monetary exchange rates, and government fiscal policies, can have a significant effect on operations. While the Company maintains reserves for anticipated liabilities, the Company could be adversely affected by civil, criminal, regulatory or administrative actions, claims, or related proceedings. Cash and Cash Equivalents The Company considers all highly liquid investments with original maturities at the date of purchase of three months or less to be cash equivalents. Cash and cash equivalents are stated at fair value and may include Investments The Company invests its excess cash balances in marketable government agency bonds, corporate debt securities and commercial paper. The Company classifies its investments as available-for-sale, reports available-for-sale investments at their fair value at each balance sheet date, and includes any unrealized holding gains and losses (the adjustment to fair value) in accumulated other comprehensive loss, a component of stockholders’ equity. Should there be any realized gains or losses, they will be determined using the specific-identification method and included as other income or expense in the statements of operations. The Company periodically evaluates whether declines in fair values of its marketable securities below their book value are other-than-temporary. This evaluation consists of several qualitative and quantitative factors regarding the severity and duration of the unrealized loss as well as the Company’s ability and intent to hold the marketable security until a forecasted recovery occurs. Additionally, the Company assesses whether it has plans to sell the security or it is more likely than not it will be required to sell any marketable securities before recovery of its amortized cost basis. Impairment assessments are made at the individual security level each reporting period. When the fair value of an available-for-sale security is less than its cost at the balance sheet date, a determination is made as to whether the impairment is other-than-temporary and, if it is other-than-temporary, an impairment loss is recognized in the statements of operations, equal to the difference between the investment’s amortized cost and fair value at such date. The Company did not record any impairment charges related to its marketable securities during the years ended December 31, 2021 and 2020. The Company classifies its available-for-sale marketable securities as non-current if such instrument’s underlying effective maturity date exceeds 12 months and for which the Company has the intent and ability to hold the investment for a period of greater than 12 months. The Company’s marketable securities at December 31, 2021 and 2020 mature in less than 12 months and are included in short-term investments in the balance sheets. Concentrations of Credit Risk and Off-balance Sheet Risk Financial instruments that potentially subject the Company to a concentration of credit risk consist primarily of cash and cash equivalents and available-for-sale marketable securities. The Company’s investment policy includes guidelines regarding the quality of the financial institutions and financial instruments and defines allowable investments that the Company believes minimizes the exposure to concentration of credit risk. The Company may invest in money market funds, U.S. Treasury securities, corporate debt, U.S. government-related agency securities, commercial paper and certificates of deposit. At December 31, 2021 and 2020, the Company’s cash and cash equivalents were held in financial institutions that management believes are creditworthy. These deposits may exceed federally insured limits. The Company has not experienced any losses historically in these accounts and believes it is not exposed to significant credit risk in its cash and cash equivalents. The Company has no significant off-balance sheet concentrations of credit risk, such as foreign currency exchange contracts, option contracts, or other hedging arrangements. Property and Equipment Property and equipment are stated at cost, subject to adjustments for impairments, less accumulated depreciation and amortization. Depreciation is calculated using the straight-line method over the useful lives of the assets as follows: Asset Estimated useful life Manufacturing and laboratory equipment Three to five years Computer hardware Three to five years Office furniture and equipment Three to five years Leasehold improvements are amortized over the shorter of their useful lives or the related lease term. Maintenance and repairs that do not improve or extend the life of the respective asset are expensed to operations as incurred. Manufacturing and laboratory equipment received is classified as construction in progress until placed into service, at which time depreciation commences. Upon disposal of an asset, the related cost and accumulated depreciation are removed from the accounts and any resulting gain or loss is included in the results of operations. Impairment of Long-lived Assets The Company evaluates whether current facts or circumstances indicate that the carrying values of its long-lived assets may not be recoverable. If such facts or circumstances are determined to exist, an estimate of the sum of the undiscounted future cash flows of these assets is compared to the carrying value the assets to determine whether impairment exists. If the assets are determined to be impaired, the loss is measured based on the difference between the sum of the undiscounted future cash flows and the carrying value of the assets. No impairment losses were recorded during the years ended December 31, 2021 or 2020. Research and Development Expenses Research and development costs are expensed as incurred. The Company’s research and development expenses consist primarily of costs incurred for the development of its product candidates and include expenses incurred under agreements with contract manufacturing organizations, or CMOs, contract research organizations, or CROs, investigative sites and consultants to conduct clinical trials and preclinical and non-clinical studies, costs to acquire, develop and manufacture supplies for clinical trials and other studies, salaries and related costs, including stock-based compensation, depreciation and other allocated facility-related and overhead expenses. Accrued Research and Development Costs The Company records accruals for estimated costs of preclinical and clinical studies and manufacturing development. The Company’s clinical and manufacturing development activities are conducted by third-party service providers, including CROs and CMOs. The financial terms of these contracts are subject to negotiation, which vary by contract and may result in payments that do not match the periods over which materials or services are provided. The Company accrues the costs incurred under the agreements based on an estimate of actual work completed in accordance with the agreements. In the event the Company makes advance payments for goods or services that will be used or rendered for future research and development activities, the payments are deferred and capitalized as a prepaid expense and recognized as expense as the goods are received or the related services are rendered. Such payments are evaluated for current or non-current classification based on when they are expected to be realized. If the Company does not identify costs that have begun to be incurred or if the Company underestimates or overestimates the level of services performed or the costs of these services, actual expenses could differ from the Company’s estimates. To date, the Company has not experienced significant changes in its estimates of preclinical studies, clinical trial and manufacturing accruals. Patent Costs Costs to secure and maintain patents covering the Company’s technology and product candidates are expensed as incurred and are classified as general and administrative expenses in the statements of operations. Convertible Preferred Stock The Company classified convertible preferred stock outside of stockholders’ equity (deficit) on its balance sheet as of December 31, 2019, as the requirements of triggering a deemed liquidation event were not within the Company’s control. In the event of a deemed liquidation event, the proceeds from the event would have been distributed in accordance with liquidation preferences of such securities. The Company would have adjusted the carrying value of the convertible preferred stock to their redemption values when it became probable a redemption event would occur. Prior to the completion of the IPO on September 24, 2020, all of the outstanding shares of convertible preferred stock automatically converted into 13,085,913 shares of common stock. Subsequent to the closing of the IPO on September 29, 2020, there were no shares of convertible preferred stock outstanding . Preferred Stock Tranche Obligation The Company’s Series C convertible preferred stock included features the Company determined were not clearly and closely related to the equity host. These features were therefore bifurcated and accounted for separately as a freestanding derivative liability on the balance sheet at its estimated fair value. This derivative liability was a result of certain investors’ rights to purchase from the Company, on the same terms as the Series C Preferred Stock Purchase Agreement executed in July 2019, additional shares of Series C convertible preferred stock in subsequent tranches based on the achievement of certain development milestones, or the Preferred Stock Tranche Obligation. At initial recognition, the Company recorded this derivative as a liability on the balance sheet at its estimated fair value. The derivative was subject to remeasurement at each balance sheet date until its expiration in September 2020, with changes in fair value recognized in change in fair value of Preferred Stock Tranche Obligation on the Company’s statements of operations. Stock-based Compensation Stock-based compensation expense related to stock options and warrants granted to employees, directors and non-employees is recognized based on the grant-date estimated fair values of the awards using the Black-Scholes option pricing model, or Black-Scholes. The valuation of restricted stock units, or RSUs, is determined at the date of grant using the Company’s closing stock price. The value is recognized as expense ratably over the requisite service period, which is generally the vesting term of the award. The Company adjusts the expense for actual forfeitures as they occur. Income Taxes The Company uses the liability method to account for income taxes. Under this method, deferred tax assets and liabilities are determined based on temporary differences between the financial statement carrying amounts of existing assets and liabilities and their tax bases. Deferred tax assets and liabilities are measured using enacted tax rates applied to taxable income in the years in which those temporary differences are expected to be recovered or settled. A valuation allowance is established when necessary to reduce deferred tax assets to the amount expected to be realized. The Company assesses the likelihood of deferred tax assets being realized. A valuation allowance is provided when it is more likely than not that some portion or all of a deferred tax asset will not be realized. For the Company, the ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the periods in which the temporary differences representing net future deductible amounts become deductible. Based on the Company’s operations to date and the uncertainty as to the timing and amount of future taxable income, the Company has recorded a full valuation allowance in all periods and for all jurisdictions. Financial statement effects of uncertain tax positions are recognized when it is more likely than not, based on the technical merits of the position, that it will be sustained upon examination. The Company evaluates uncertain tax positions on a regular basis. The evaluations are based on a number of factors, including changes in facts and circumstances, changes in tax law, correspondence with tax authorities during the course of an audit, and effective settlement of audit issues. Interest and penalties related to unrecognized tax benefits would be included within the income tax provision. Net Loss Per Share The Company calculates basic and diluted net loss per share attributable to common stockholders in conformity with the two-class method required for participating securities. While it was outstanding, the Company considered its convertible preferred stock to be participating securities as, in the event a dividend was paid on common stock, the holders of convertible preferred stock and unvested shares of common stock would have been entitled to receive dividends on a basis consistent with the common stockholders. The net loss attributable to common stockholders was not allocated to the convertible preferred stock as the holders of those securities did not have a contractual obligation to share in losses. Cumulative dividends on preferred stock were added to net loss to arrive at net loss available to common stockholders. Under the two-class method, basic net loss per share attributable to common stockholders is computed by dividing the net loss attributable to common stockholders by the weighted-average number of common shares outstanding during the period, without consideration of potential dilutive securities. Diluted net loss per share is calculated by dividing net loss by the weighted-average number of shares of common stock and potential dilutive common stock equivalents outstanding during the period if the effect is dilutive. Potentially dilutive securities include warrants, stock options, RSUs and convertible preferred stock. Likewise, adjustments to the denominator are required to reflect the related dilutive shares. In all periods presented, the Company’s outstanding stock options, RSUs, convertible preferred stock, common stock warrants, and the potential issuance of additional preferred shares from the Preferred Stock Tranche Obligation were excluded from the calculation of diluted net loss per share because their effects were antidilutive and the development milestones for the issuance of additional shares from the P referred S tock T ranche Obligation were not achieved prior to its expiration in September 2020 . Related Party Transactions In August 2019, the Company engaged a consulting firm managed by the then acting chief financial officer of the Company for professional services related to finance and other administrative functions. For the year ended December 31, 2020, the costs incurred under this arrangement totaled $657,000 and were recorded as general and administrative expense in the accompanying statement of operations. The Company terminated its relationship with this entity in September 2020. Segments Operating segments are defined as components of an entity for which separate financial information is available and that is regularly reviewed by the chief operating decision maker, or CODM, in deciding how to allocate resources to an individual segment and in assessing performance. The Company’s CODM is its chief executive officer. The Company has determined it operates in one segment. Comprehensive Loss Comprehensive loss is defined as the change in equity of a business enterprise during a period arising from transactions and other events and circumstances from non-owner sources. The Company’s comprehensive loss is comprised of changes in unrealized (loss) gain on available-for-sale securities. Recently Issued Accounting Pronouncements In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) In June 2016, the FASB issued ASU 2016-13, Financial Instruments-Credit Losses: Measurement of Credit Losses on Financial Instruments Codification Improvements to Topic 326, Financial Instruments-Credit Losses, Topic 815, Derivatives and Hedging and Topic 825, Financial Instruments In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2021
Fair Value Disclosures [Abstract]
Fair Value Measurements	3. Fair Value Measurements The Company utilizes valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs to the extent possible. The Company determines fair value based on assumptions that market participants would use in pricing an asset or liability in the principal or most advantageous market. When considering market participant assumptions in fair value measurements, the following fair value hierarchy distinguishes between observable and unobservable inputs, which are categorized in one of the following three levels: • Level 1: Observable inputs such as unadjusted quoted prices in active markets for identical assets or liabilities at the measurement date. • Level 2: Inputs (other than quoted prices included in Level 1) that are either directly or indirectly observable for the asset or liability. These include quoted prices for similar assets or liabilities in active markets and quoted prices for identical or similar assets or liabilities in markets that are not active. • Level 3: Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. The following tables present information about the Company’s financial assets and liabilities measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values (in thousands): December 31, 2021 Level 1 Level 2 Level 3 Total Current assets: Cash equivalents: Money market funds $ 8,920 $ — $ — $ 8,920 Corporate debt securities — 1,480 — 1,480 Commercial paper — 2,749 — 2,749 Total cash equivalents 8,920 4,229 — 13,149 Short-term investments: Corporate debt securities — 1,117 — 1,117 Commercial paper — 41,954 — 41,954 U.S. Treasury notes — 7,235 — 7,235 Total short-term investments — 50,306 — 50,306 Total assets measured at fair value $ 8,920 $ 54,535 $ — $ 63,455 December 31, 2020 Level 1 Level 2 Level 3 Total Current assets: Cash equivalents: Money market funds $ 15,677 $ — $ — $ 15,677 Corporate debt securities — 2,500 — 2,500 Commercial paper — 13,499 — 13,499 Total cash equivalents 15,677 15,999 — 31,676 Short-term investments: Corporate debt securities — 11,588 — 11,588 Commercial paper — 50,027 — 50,027 Total short-term investments — 61,615 — 61,615 Total assets measured at fair value $ 15,677 $ 77,614 $ — $ 93,291 The following tables present information as to cost, unrealized gains and losses and fair value determination of the Company’s financial assets measured at fair value on a recurring basis (in thousands): December 31, 2021 Amortized Cost Unrealized Gains Unrealized Losses Aggregate Fair Value Current assets: Cash equivalents: Money market funds $ 8,920 $ — $ — $ 8,920 Corporate debt securities 1,480 — — 1,480 Commercial paper 2,749 — — 2,749 Total cash equivalents 13,149 — — 13,149 Short-term investments: Corporate debt securities 1,117 — (1 ) 1,116 Commercial paper 41,956 6 (8 ) 41,954 U.S. Treasury notes 7,249 — (13 ) 7,236 Total short-term investments 50,322 6 (22 ) 50,306 Total assets measured at fair value $ 63,471 $ 6 $ (22 ) $ 63,455 December 31, 2020 Amortized Cost Unrealized Gains Unrealized Losses Aggregate Fair Value Current assets: Cash equivalents: Money market funds $ 15,677 $ — $ — $ 15,677 Corporate debt securities 2,502 — (2 ) 2,500 Commercial paper 13,498 1 — 13,499 Total cash equivalents 31,677 1 (2 ) 31,676 Short-term investments: Corporate debt securities 11,588 1 (1 ) 11,588 Commercial paper 50,030 2 (5 ) 50,027 Total short-term investments 61,618 3 (6 ) 61,615 Total assets measured at fair value $ 93,295 $ 4 $ (8 ) $ 93,291 Money market funds are highly liquid investments which are actively traded. The pricing information on the Company’s money market funds is based on quoted prices in active markets for identical securities. This approach results in the classification of these securities as Level 1 of the fair value hierarchy. The fair value of short-term investments is determined from market pricing and other observable market inputs for similar securities obtained from various third-party data providers. The pricing services 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. This approach results in the classification of these securities as Level 2 of the fair value hierarchy. As of December 31, 2021 and 2020, the contractual maturities of all available-for-sale investments were less than 12 months. The Company periodically reviews the available-for-sale investments for other-than-temporary impairment loss. All investments with unrealized losses have been in a loss position for less than 12 months. As a result, the Company did not recognize any other-than-temporary impairment losses as of December 31, 2021 and 2020. There were no transfers between Levels 1, 2 or 3 for the periods presented.

Balance Sheet Components

Balance Sheet Components	12 Months Ended
	Dec. 31, 2021
Balance Sheet Related Disclosures [Abstract]
Balance Sheet Components	4. Balance Sheet Components Property and Equipment, net Property and equipment, net, consisted of the following (in thousands): December 31, 2021 2020 Manufacturing and laboratory equipment $ 2,511 $ 2,179 Computer hardware 28 28 Office furniture and equipment 28 28 Leasehold improvement 234 234 Construction in progress 833 611 Total property and equipment, at cost 3,634 3,080 Less: accumulated depreciation (1,653 ) (1,134 ) Property and equipment, net $ 1,981 $ 1,946 Depreciation expense for the years ended December 31, 2021 and 2020 was $519,000 and $395,000, respectively. Prepaid Expenses and Other Current Assets Prepaid expenses and other current assets consisted of the following (in thousands): December 31, 2021 2020 Prepaid expenses $ 1,866 $ 2,140 Prepaid clinical and research expenses 168 6 Interest and other receivables 21 598 Other current assets 1,353 1,463 Total prepaid expenses and other current assets $ 3,408 $ 4,207 Other Current Liabilities Other current liabilities consisted of the following (in thousands): December 31, 2021 2020 Salaries and benefits $ 2,278 $ 2,302 Professional services 461 425 Deferred rent 8 27 Other 479 374 Total other current liabilities $ 3,226 $ 3,128

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2021
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	5. Commitments and Contingencies The Company enters into contracts in the normal course of business with CROs for clinical trials and CMOs for clinical supply manufacturing and with vendors for equipment, preclinical research studies, research supplies and other services and products for operating purposes. As of December 31, 2021, these commitments were approximately $0.8 million due within 3 to 15 months. These contracts generally provide for termination on notice of 60 to 90 days. During the year ended December 31, 2021, the Company terminated several contracts with its equipment vendors and CMOs. The termination of these contracts resulted in the cancellation of commitments totaling $3.7 million as of December 31, 2020. From this amount, the Company recognized $2.2 million in general and administrative expenses in the Company’s statement of operations for the write-off of $1.3 million in equipment deposits and $0.9 million in other commitments and cancellation fees. As of December 31, 2021, there were no unpaid cancellation or other related costs and none are anticipated. Operating Lease Agreements The Company leases a facility in Baltimore, Maryland under an operating lease with a term through June 2023. On July 29, 2021, the Company entered into a lease agreement for approximately 2,560 rentable square feet of office space in Redwood City, California. The lease commenced on August 18, 2021 with a 12-month initial term expiring on August 31, 2022. This new facility replaced the Company’s existing Redwood City lease when it expired on August 31, 2021. Upon execution of the lease, the Company delivered to the lessor a sum of $31,000, consisting of a security deposit and one month's rent. The total lease obligation over the term of the lease will be approximately $0.2 million. Rent expense for the Company’s facility leases was $0.7 million for each of the years ended December 31, 2021 and 2020. Future minimum lease payments under the Company’s non–cancelable operating leases as of December 31, 2021 were as follows (in thousands): Year ended December 31: 2022 $ 527 2023 205 Total future minimum lease payments $ 732 License Agreements Johns Hopkins University In June 2011, the Company entered into an Exclusive License Agreement with Johns Hopkins University, or JHU, which has been amended from time to time, such agreement as amended is referred to as the JHU Agreement. Pursuant to the JHU Agreement, JHU granted the Company an exclusive, worldwide, sublicensable license to three patent families to research, develop, make, use and sell products and provide services in any field, and a non-exclusive license to use specified know-how and materials with a provision that JHU will not grant a license to know how and materials to any other commercial entity. The JHU first patent family describes microparticles with a hydrophobic polymeric core (such as poly(lactic-co-glycolic acid), or PLGA, poly-lactic acid, or PLA, or a combination of both PLGA and PLA) and a hydrophilic coating (such as PLGA permanently linked to polyethylene glycol) to reduce inflammation for intraocular injections and their methods of use, which technology is incorporated into the Company’s GB-102 and GB-401 product candidates. The JHU licensed fourth and fifth patent families cover potential future technologies. In September 2015, the JHU Agreement was amended to include the JHU second patent family which covers sunitinib-encapsulated polymeric microparticles, including GB-102, and their use as therapeutic compositions to treat disorders of the eye. Under the terms of the amended JHU Agreement, the Company paid a one-time, non-refundable upfront fee, with a remaining amount to be paid upon the occurrence of certain events. The Company also agreed to pay an additional one-time, non-refundable fee of $100,000 on the occurrence of the first commercial sale of a product falling under the claims of a patent in the second patent family. In April 2016, the JHU Agreement was further amended to include a third patent family which discloses a method for reducing neuronal damage in the eye that includes administration of a sustained release formulation of a dual leucine kinase inhibitor in a polymeric particle, and wherein the dual leucine kinase inhibitor may be sunitinib, and thus is relevant to both the Company’s GB-102 and GB-103 product candidates. Under the terms of the amended JHU Agreement, the Company paid a one-time, non-refundable upfront fee, and a milestone payment for the grant of the first patent. The Company also agreed to use its best efforts to develop a licensed product under the third patent family and enter into a Phase I clinical trial on or before April 2019, and to have cumulatively spent several million dollars on research and development within six years of execution of the amendment. Upon execution of the JHU Agreement in 2011, the Company paid JHU an upfront license fee in the low tens of thousands of dollars and issued to JHU a low single digit percentage of the Company’s equity interests as of such date. The Company also reimbursed JHU for the prosecution and maintenance costs incurred by JHU for the licensed patent rights prior to the Company entering into the JHU Agreement, and the Company is responsible for all of the ongoing costs relating to the prosecution and maintenance of the JHU patent rights licensed to the Company. The Company also agreed to pay minimum annual royalties in the tens of thousands of dollars per year until the first commercial sale of a licensed product or service. The JHU Agreement further requires single-digit running royalties on the Company’s annual net sales, which may be reduced by 50% of any payments the Company makes to third parties for freedom to operate, up to a maximum credit of 50% of the running royalty rate otherwise due to JHU. Royalties must be paid on products that fall within a patent claim of an issued and unexpired patent or a pending patent application that has not been finally rejected or is pending for less than seven years. The Company also must pay developmental milestones for achieving certain clinical progression events, ranging from tens of thousands to hundreds of thousands dollars per event, which in the aggregate, total less than $2.0 million per product. Under the JHU Agreement, prior to the Kala Agreement renegotiation described below, the Company was responsible for paying each developmental milestone payment for the first three products to achieve such milestone, and milestones for the second and third products are reduced by 50%. The Company further agreed to pay a percentage of any sublicense consideration the Company receives. The JHU Agreement will remain effective until (i) the later of the expiration date of the last-to-expire patents covered under the JHU Agreement or 20 years from the effective date; (ii) the termination by either party upon the bankruptcy or uncured breach of the other party or (iii) if the Company terminates the JHU Agreement, with a 90-day notification period. The Company may terminate the entire agreement or on a patent by patent basis if desired, subject to the 90-day notification period. Milestone and royalty expenses under the JHU Agreement are classified as research and development expense and reimbursement of patent-related expenditures are classified as general and administrative expense in the statements of operations. Expense under the JHU Agreement is as follows (in thousands): Year Ended December 31, 2021 2020 Research and development $ 38 $ 38 General and administrative 160 165 Total JHU Agreement expense $ 198 $ 203 Kala Pharmaceuticals, Inc. A dispute arose between the Company, JHU and Kala Pharmaceuticals, Inc., or Kala, over rights licensed to the Company and Kala by JHU. In October 2014, the Company entered into a Settlement and License Agreement, or the Kala Agreement, with Kala and JHU, which settled all pending disputes and amended the Company’s and Kala’s existing license agreements with JHU and created new rights and obligations among the parties. Under the Kala Agreement, each of Kala and the Company provided the other with a royalty-free, exclusive sublicense with respect to certain intellectual property rights granted by JHU in limited fields of use. Specifically, the Company provided Kala with an exclusive sublicense for the use of a particle with specific characteristics for delivery of a biologically active material through mucus, mucin, or a mucosal barrier (provided that such delivery does not involve administration via injection to the eye), or the Kala Field of Use, and Kala provided the Company with an exclusive sublicense to the use of a particle with specific characteristics for delivery of a biologically active material to the eye via injection (excluding such use of any particle comprising or consisting of loteprednol etabonate). Kala also agreed not to use a particle with those specific characteristics that include sunitinib in any technology licensed the Kala Field of Use under the license from the Company or JHU. Neither the Company nor Kala owe JHU any payments under its existing JHU agreement with respect to the sublicenses granted to the other. Both the Company and Kala hold rights to sublicense the Company’s respective rights in connection with a future collaboration arrangement and subject to any such sublicensee being bound by the applicable terms of the Kala Agreement. Under the Kala Agreement, JHU agreed to a number of financial concessions to both the Company and Kala. The payments under the existing JHU agreements were modified by reducing all milestones and minimum annual royalties by 25%, including the development milestone payments due for the first licensed product; the development milestone payments due for the first license product were each extended by one year; development milestone payments for the second and third licensed products were eliminated; and the commercial milestone payments for the first commercial sale of a licensed product were reduced by 50% in the United States. New sales-based milestones were added for the second and third licensed products. Upon the second licensed product under the JHU Agreement reaching a certain level of sales or receiving sublicense royalty income, the Company is required to pay $100,000 plus the amounts of the eliminated development milestones and reduced first commercial sale milestone. For the third licensed product, on reaching the same level of sales or receiving sublicense royalty income, the Company is required to pay $150,000 plus the amounts of the eliminated development milestones and reduced first commercial sale milestone. In addition, the Company, Kala and JHU released each other from any liability or claims known to Kala and the Company as of the Kala Agreement and arising out of the actions leading to, and related to the subject of, the Kala Agreement. The Kala Agreement will expire upon the expiration of all the patent rights that are the subject of the agreement. The Company may terminate one or more of the licenses or sublicenses granted to the Company in the Kala Agreement on a country-by-country basis for convenience upon 30 days’ prior written notice to Kala. The Company or Kala may terminate one or more of the sublicenses granted to the other party under the JHU patent rights if the other party, or its employees, officers, directors, agents or representatives, takes certain steps to oppose, attempt to invalidate or prevent the issuance of any of the patent rights directly licensed to the terminating party by JHU. There have been no expenses under the Kala Agreement in the years ended December 31, 2021 or 2020 and no amounts payable at December 31, 2021 or 2020. AffaMed Project Limited In July 2019, the Company entered into a letter agreement with AffaMed Project Limited, or AffaMed, in connection with their purchase of the Company’s Series C convertible preferred stock, or the AffaMed Letter. Under the AffaMed Letter, the Company granted AffaMed a right of first negotiation, or the Option, to exclusively develop, register and commercialize GB-102 solely in the territories of China, Hong Kong, Taiwan, Macau and South Korea. The Option expires upon the earlier of (i) July 31, 2021 and (ii) 60 days after the Company provides top line data from the Phase 2b ALTISSIMO trial for GB-102. AffaMed did not exercise the Option, and the Company has no further obligation to AffaMed to license rights to GB-102. There have been no expenses under the Affamed Letter in the years ended December 31, 2021 or 2020 and no amounts payable at December 31, 2021 or 2020. Asset Acquisition In December 2021, the Company entered into an Assignment and Licensing Agreement with a private company, pursuant to which the Company acquired certain intellectual property rights, including patents and know-how, related to new cyclic monophosphate (cGMP) compounds for the treatment of ocular disorders. As consideration for the intellectual property rights acquired, the Company made an upfront cash payment of $0.5 million and may be required to make additional contingent payments of up to $27.0 million in the aggregate upon achievement of certain development and regulatory milestones. Additionally, upon commercialization, the Company may be required to make tiered single-digit royalty payments based on net product sales. As the acquired rights relate to in-process research and development activities that have no alternative future use to the Company, the upfront payment of $0.5 million was recorded as research and development expense in the accompanying statements of operations for the year ended December 31, 2021. As of December 31, 2021, no development or regulatory milestones were deemed probable of achievement and, accordingly, no amounts have been recognized in the accompanying financial statements with respect to these contingent payments. In March 2022, the Company acquired a private company in the United States with certain gene therapy technology and preclinical data. The private company was purchased at a cost of approximately $2.0 million, including estimated transaction costs and a contingent holdback, and the Company may be required to make additional contingent payments of up to $20.0 million in the aggregate upon the achievement of certain milestones. Other than the contingent holdback release, no further payments are required until FDA approval of a product based upon the acquired assets and the sale or utilization of any priority review voucher that may be granted in connection with such approval. Indemnification The Company, as permitted under Delaware law and in accordance with its certification of incorporation and bylaws and pursuant to indemnification agreements with certain of its officers and directors, indemnifies its officers and directors for certain events or occurrences, subject to certain limits, which the officer or director is or was serving at the Company’s request in such capacity. The Company enters into certain types of contracts that contingently require the Company to indemnify various parties against claims from third parties. These contracts primarily relate to (i) the Company’s bylaws, under which the Company must indemnify directors and executive officers, and may indemnify other officers and employees, for liabilities arising out of their relationship, (ii) contracts under which the Company must indemnify directors and certain officers and consultants for liabilities arising out of their relationship, and (iii) procurement, service or license agreements under which the Company may be required to indemnify vendors, service providers or licensees for certain claims, including claims that may be brought against them arising from the Company’s acts or omissions with respect to the Company’s products, technology, intellectual property or services. From time to time, the Company may receive indemnification claims under these contracts in the normal course of business. In the event that one or more of these matters were to result in a claim against the Company, an adverse outcome, including a judgment or settlement, may cause a material adverse effect on the Company’s future business, operating results or financial condition. It is not possible to determine the maximum potential amount potentially payable under these contracts since the Company has no history of prior indemnification claims and the unique facts and circumstances involved in each particular claim will be determinative. Litigation From time to time, the Company may become involved in legal proceedings arising in the ordinary course of business. The Company is not presently a party to any legal proceedings that it believes would have a material adverse effect on its business, operating results, financial condition or cash flows.

Convertible Preferred Stock and

Convertible Preferred Stock and Preferred Stock Tranche Obligation	12 Months Ended
	Dec. 31, 2021
Temporary Equity Disclosure [Abstract]
Convertible Preferred Stock and Preferred Stock Tranche Obligation	6. Convertible Preferred Stock and Preferred Stock Tranche Obligation The following table summarizes outstanding convertible preferred stock as of December 31, 2019 (in thousands, except share amounts): Shares Authorized Shares Outstanding Net Carrying Value Liquidation Preference Series A 2,280,000 2,280,000 $ 2,280 $ 2,280 Series A-2 2,018,561 2,018,561 1,605 1,740 Series B 76,078,535 76,078,535 74,926 87,729 Series C 61,773,000 37,432,787 52,552 56,843 Total 142,150,096 117,809,883 $ 131,363 $ 148,592 In July 2019, the Company authorized the sale of up to 61,773,000 shares of its Series C Convertible Preferred Stock, or Series C, at a price of $1.4693 per share, or Series C Financing. In July and August 2019, the Company issued 37,432,787 shares of Series C for aggregate gross proceeds of $55.0 million. In connection with this financing, certain purchasers of the Series C had the option to purchase up to an additional 17,014,902 shares of Series C at a price per share of $1.4693 for a period of up to 30 days after the Company notified them of the three-month readout from the Phase 2a clinical trial of GB-102 in patients with macular edema secondary to diabetic macular edema and retinal vein occlusion, or the Preferred Stock Tranche Obligation. The Company concluded that the Preferred Stock Tranche Obligation met the definition of a freestanding financial instrument, as the rights were legally detachable and separately exercisable from the Series C. Therefore, the Company allocated the proceeds received from the issuance of shares under the Series C Preferred Stock Purchase Agreement between the Preferred Stock Tranche Obligation and the Series C. The fair value of the Preferred Stock Tranche Obligation of $2.2 million on issuance was allocated from the $55.0 million proceeds of the Series C Financing and classified as a current liability on the balance sheet as the Series C would become redeemable upon a deemed liquidation event, the occurrence of which was not within the Company’s control. In September 2020, the board of directors and the Series C investors amended the Series C stock purchase agreement such that the Preferred Stock Tranche Obligation was no longer exercisable and expired upon the effectiveness of the Company’s IPO registration statement. As a result, the liability for the Preferred Stock Tranche Obligation was permanently eliminated as of September 24, 2020. Due to the low probability of the Preferred Stock Tranche Obligation being settled, the fair value immediately prior to the IPO was immaterial. Prior to the completion of the IPO on September 24, 2020, all of the outstanding shares of convertible preferred stock automatically converted into 13,085,913 shares of common stock. Subsequent to the closing of the IPO on September 29, 2020, there were no shares of convertible preferred stock outstanding. The rights and preferences and privileges of convertible preferred stock are described below: Dividend Rights The holders of Series C Preferred, in preference to holders of Series B Preferred, Series A-2 Preferred, Series A Preferred and common stock, are entitled to receive cumulative dividends on each outstanding share payable when declared by the board of directors of $0.117544 per share. After payment of such dividends on the Series C Preferred, the holders of Series B Preferred, in preference to holders of Series A-2 Preferred, Series A Preferred and common stock, are entitled to receive cumulative dividends on each outstanding share payable when declared by the board of directors of $0.06937 per share. After payment of such dividends on the Series B Preferred, the holders of Series A-2 Preferred, in preference to the holders of Series A Preferred and common stock, are entitled to receive non-cumulative dividends on each outstanding share payable when declared by the board of directors of $0.06034 per share. After payment of such dividends on the Series A-2 Preferred, the holders of Series A Preferred, in preference to the holders of common stock, are entitled to receive non-cumulative dividends on each outstanding share payable when declared by the board of directors of $0.08 per share. The board of directors has not declared any dividends to-date. Conversion Rights Each share of convertible preferred stock is convertible at the option of the holder, at any time after the date of issuance, into a fully paid and non-assessable share of common stock. Each share of convertible preferred stock is convertible into that number of common shares as is determined by dividing the applicable original purchase price of such share by the applicable conversion price. The conversion rate is subject to adjustment upon the occurrence of certain events. The conversion rates for the Series C Preferred, Series B Preferred and Series A-2 Preferred is 9.0058:1 and for the Series A Preferred is 8.8527:1. All shares of the convertible preferred stock automatically convert upon the closing of a firm commitment underwritten initial public offering of common stock, in which the price per share is at least $14.56 per share, subject to adjustment, resulting in gross proceeds of at least $40.0 million. The conversion price for each series of convertible preferred stock is subject to adjustment in the event of stock split, combination, common stock dividend or distribution, reclassification, exchange, substitution, reorganization, and certain antidilution adjustments. Liquidation Rights In the event of any liquidation, dissolution, or winding up of the Company or a deemed liquidation event, the holders of Series C Preferred are entitled to receive, prior to any distribution made to any other class of security, an amount equal to $1.4693 per share, plus any dividends accrued and declared but unpaid. Upon distribution to holders of Series C Preferred, the holders of Series B Preferred are entitled to receive, prior to distribution to holders of Series A-2 Preferred, Series A Preferred and common stock, an amount equal to $0.991 per share, plus any dividends accrued and declared but unpaid. Upon distribution to holders of Series C Preferred and Series B Preferred, the holders of Series A-2 Preferred are entitled to receive, prior to distribution to holders of Series A Preferred and common stock, an amount equal to $0.862 per share, plus any dividends declared but unpaid. Upon distributions to the holders of Series C Preferred, Series B Preferred and Series A-2 Preferred, the holders of Series A Preferred are entitled to receive, prior to any distribution or payment to the holders of common stock, an amount equal to $1.00 per share, plus any dividends declared but unpaid. Upon the completion of the distribution to the holders of Series C Preferred, Series B Preferred, Series A-2 Preferred and Series A Preferred, any remaining assets available for distribution will be distributed among the holders of the shares of Series C Preferred, Series B Preferred, Series A-2 Preferred, Series A Preferred and common stock, on a pro rata basis on the number of shares held by each such holder, treating each share as if they had been converted to common stock immediately prior to such liquidation, dissolution or winding up of the Company. Voting Rights Each share of Series A Preferred has voting rights equal to the number of common shares into which the Series A Preferred can be converted. Shares of Series A-2 Preferred, Series B Preferred and Series C Preferred do not have voting rights. The holders of Series C Preferred are entitled to elect one director of the Company; the holders of Series B Preferred are entitled to elect three directors of the Company; the holders of Series A-2 Preferred, are entitled to elect one director; the holders of common stock are entitled to elect one director; and holders of common stock and any other class or series of voting stock, exclusively and voting together as a single class on an as-converted basis, are entitled to elect one director. Holders of Series A Preferred are not entitled to a director of the Company. Redemption Rights Shares of Series C Preferred, Series B Preferred and Series A-2 Preferred may be redeemed at the greater of the fair market value or the original issue price for the applicable series of convertible preferred stock plus any dividends accrued but unpaid with respect to the Series C Preferred and the Series B Preferred and any dividend declared by unpaid with respect to the Series A-2 Preferred. A redemption will occur upon a written request from the holders of a majority of the then outstanding shares of Series C Preferred, voting exclusively as a separate series, and the holders of a majority of the Series B Preferred and Series A-2 Preferred, voting together on an as-converted basis, which request can be made at any time after July 2024. Cumulative dividends and accretion of discount on Series A-2 Preferred, Series B Preferred and Series C Preferred, together the Contingently Redeemable Preferred, is not recorded until the Contingently Redeemable Preferred is probable of becoming redeemable. As of December 31, 2019, the Company has determined that the Contingently Redeemable Preferred are not currently probable of becoming redeemable and, as such, the cumulative dividend and accretion of discount on the Contingently Redeemable Preferred has not been recorded.

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation	7. Stock-Based Compensation 2020 Equity Incentive Plan In August 2020, the Company’s board of directors and stockholders adopted the Company’s 2020 Equity Incentive Plan, or the 2020 Plan, that became effective in connection with the IPO , and serves as the successor to the Company’s 2015 Stock Incentive Plan, or the 2015 Plan. The Company’s 2020 Plan authorizes the award of stock options, restricted stock units, or RSUs, restricted stock awards, or RSAs, stock appreciation rights, or SARs, performance awards and stock bonus awards. The Company plus any reserved not issued or subject to outstanding grants of the 2020 Plan, for issuance pursuant to awards granted under the 2020 Plan. The aggregate number of shares reserved for sale under the 2020 Plan will increase automatically on each January 1st of 2021 through 2030 by the number of shares equal to 5 % of the aggregate number of outstanding shares of the Company’s common stock as of the immediately preceding December 31, or a lesser number as may be determined by the Company’s board of directors . In conjunction with adopting the 2020 Plan, the Company may not grant any additional stock-based awards under the 2015 Plan, and any shares available for issuance under the 2015 Plan were added to the shares reserved under the 2020 Plan. The 2015 Plan will continue to govern outstanding stock-based awards granted thereunder. On January 1, 2021, the aggregate number of shares reserved for issuance was increased by an additional 1,048,963 shares pursuant to the automatic share reserve increase provision of the 2020 Plan. As of December 31, 2021, there were 445,617 shares available for issuance under the 2020 Plan. 2020 Employee Stock Purchase Plan In August 2020, the Company’s board of directors and stockholders adopted the Company’s 2020 Employee Stock Purchase Plan, or the ESPP, that became effective in connection with the IPO Inducement Grants On January 14, 2022, six newly-hired employees were granted inducement options to purchase an aggregate of 234,200 shares of the Company’s common stock at an exercise price of $1.55 per share. These inducement grants were made outside of the 2020 Equity Incentive Plan in accordance with the Nasdaq Listing Rule 5635(c)(4). One-fourth ten-year Stock Option Activity The following summarizes stock option activity: Weighted Weighted Average Average Remaining Aggregate Number of Exercise Contractual Intrinsic Options Price Term Value (In years) (In thousands) Outstanding—December 31, 2020 2,756,102 $ 8.28 8.6 $ 57,090 Granted 1,649,500 $ 3.74 Exercised (353,508 ) $ 1.97 Forfeited and Canceled (274,696 ) $ 12.52 Outstanding—December 31, 2021 3,777,398 $ 6.58 8.4 $ 41,967 Options Exercisable—December 31, 2021 1,705,619 $ 5.24 7.4 $ 41,967 At December 31, 2021, the aggregate intrinsic value of options granted is calculated as the difference between the exercise price and the closing price on the same date. The aggregate intrinsic value of options exercised in the years ended December 31, 2021 and 2020 was $2.5 million and $113,000, respectively. The aggregate fair value of options that vested during the years ended December 31, 2021 and 2020 was $4.0 million and $1.4 million, respectively. The weighted-average grant-date fair value per share of options that vested during the years ended December 31, 2021 and 2020 was $6.06 and $2.43, respectively. Restricted Stock Units The following table summarizes restricted stock units (RSUs) activity for the year ended December 31, 2021: RSUs Outstanding Number of Restricted Stock Units Weighted-Average Grant Date Fair Value Per Share Balance - December 31, 2020 80,000 $ 16.50 Granted 988,700 $ 3.73 Vested (25,000 ) $ 16.50 Cancelled/forfeited (74,000 ) $ 3.74 Balance - December 31, 2021 969,700 $ 4.45 The fair value of RSUs is determined on the date of grant based on the market price of the Company’s common stock on that date. The aggregate fair value of RSUs vested during the year ended December 31, 2021 was $0.4 million. No RSUs vested during the year ended December 31, 2020. Fair Value of Stock Option Awards The Company estimates the fair value of stock option awards on the grant date using Black-Scholes. The weighted-average grant date fair value per option granted during the years ended December 31, 2021 and 2020 was $2.72 and $11.90, respectively. The fair value of each award is estimated using Black-Scholes based on the following assumptions: Year Ended December 31, 2021 2020 Expected term (years) 5.1-6.1 5.0-6.1 Expected volatility 87% - 88% 85% Risk-free interest rate 0.84%-1.12% 0.25%-0.53% Expected dividend — — Black-Scholes requires the use of subjective assumptions which determine the fair value of stock-based awards. These assumptions include: Expected Term : The expected term represents the period that options 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 the contractual term. Expected Volatility : The expected volatility is estimated based on the average volatility for comparable publicly-traded biopharmaceutical companies over a period equal to the expected term of the stock option grants as the Company does not yet have sufficient historical trading history for its own stock. The comparable companies are chosen based on their similarities to the Company, including life cycle stage, therapeutic focus and size. The Company will continue to apply this method until a sufficient amount of historical information over a period equal to the expected term of the stock-based awards becomes available. Risk-free Interest Rate . The risk-free interest rate is based on the U.S. Treasury zero coupon issues in effect at the time of grant for periods corresponding with the expected term of the stock option grants. Expected Dividend : The Company has never paid dividends on its common stock and has no plans to pay dividends on its common stock. Therefore, the Company used an expected dividend yield of zero. Stock-Based Compensation Expense Stock-based compensation expense is classified as follows (in thousands): Year Ended December 31, 2021 2020 Research and development $ 1,210 $ 390 General and administrative 4,165 1,398 Total stock-based compensation expense $ 5,375 $ 1,788 As of December 31, 2021, the total unrecognized stock-based compensation expense related to outstanding unvested stock awards that are expected to vest was $15.4 million, which the Company expects to recognize over an estimated weighted-average term of 2.8 years.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Income Taxes	8. Income Taxes The Company has incurred net operating losses for all the periods presented. The Company has not reflected the benefit of any such net operating loss carryforwards in the accompanying financial statements. The effective tax rate for the years ended December 31, 2021 and 2020 is different from the federal statutory rate primarily due to the valuation allowance against deferred tax assets as a result of insufficient sources of income. The reconciliation of the federal statutory income tax rate to the Company’s effective income tax rate is as follows: Year Ended December 31, 2021 2020 Income tax benefit at the federal statutory rate 21.0 % 21.0 % State income taxes, net of federal benefit 0.6 3.2 Research and development tax credits 1.4 1.3 Other (0.4 ) (0.6 ) Mark to market gain/loss — 1.7 Change in valuation allowance (22.6 ) (26.6 ) Total — % — % Deferred income taxes reflect the net effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. The principal components of the Company’s net deferred tax assets consisted of the following (in thousands): December 31, 2021 2020 Deferred tax assets Federal and state net operating loss carryforwards $ 34,431 $ 27,567 Research and development tax credits 5,408 4,887 Other 1,408 748 Gross deferred tax assets 41,247 33,202 Less: valuation allowance (41,215 ) (33,141 ) Total deferred tax assets 32 61 Deferred tax liabilities Depreciation (32 ) (61 ) Total deferred tax liabilities (32 ) (61 ) Net deferred tax assets $ — $ — The Company has incurred annual net operating losses in each year since inception. The Company has not reflected the benefit of any such net operating loss carryforwards in the financial statements. Due to the Company’s history of losses, and lack of other positive evidence, the Company has determined that it is more likely than not that its net deferred tax assets will not be realized and, therefore, the net deferred tax assets are fully offset by a valuation allowance at December 31, 2021 and 2020. The Company increased its valuation allowance by $8.1 million for the year ended December 31, 2021 in order to maintain a full valuation allowance against its deferred tax assets. As of December 31, 2021, the Company had federal net operating loss carryforwards, or NOLs, of $157.4 million and federal tax credits of $6.1 million available to offset tax liabilities. The Company’s federal NOLs and federal tax credit carryforwards begin to expire in 2035 and 2036, respectively. Of the federal NOLs, $123.3 million have an indefinite life. The Company also had gross state NOLs of $23.3 million and state tax credits of $1.8 million which are available to offset state tax liabilities. The state NOLs expire in 2036 and the state tax credit carryforwards can be carried forward indefinitely. Federal and state NOLs and tax credit carryforwards are also subject to annual limitations in the event that cumulative changes in the ownership interests of significant stockholders exceed 50% over a three-year period, as defined under Sections 382 and 383 of the Internal Revenue Code of 1986. The Company has not completed an analysis to determine if the NOLs and tax credits are limited due to a change in ownership. Should there be ownership changes that occurred, the Company’s ability to utilize existing carryforwards could be substantially restricted. The Company determines its uncertain tax positions based on whether and how much of a tax benefit taken by the Company in its tax filings is more likely than not to be sustained upon examination by the relevant income tax authorities. A reconciliation of the unrecognized tax benefit is as follows (in thousands): Year Ended December 31, 2021 2020 Balance—beginning of year $ 1,981 $ 1,406 Addition based on tax position related to current year 257 406 (Reduction) addition based on tax position related to prior year (148 ) 169 Balance—end of year $ 2,090 $ 1,981 The unrecognized tax benefits, if recognized, would not have an impact on the Company’s effective tax rate assuming the Company continues to maintain a full valuation allowance position. Based on prior year’s operations and experience, the Company does not expect a significant change to its unrecognized tax benefits over the next twelve months. The unrecognized tax benefits may increase or change during the next year for unexpected or unusual items for items that arise in the ordinary course of business. The Company has elected to include interest and penalties as a component of tax expense. During the years ended December 31, 2021 and 2020, the Company did not recognize accrued interest and penalties related to unrecognized tax benefits. The Company files income tax returns in the U.S., California, and several other state jurisdictions. Due to net operating loss carryforwards, all years remain open for income tax examination, however, the Company is not currently under examination by any taxing authority for any open tax year.

Employee Retirement Plan

Employee Retirement Plan	12 Months Ended
	Dec. 31, 2021
Compensation And Retirement Disclosure [Abstract]
Employee Retirement Plan	9. Employee Retirement Plan The Company maintains a 401(k) retirement savings plan, or 401(k) Plan. The 401(k) Plan allows employees to make contributions up to the maximum allowable by the IRS. The Company did not make any contributions to the 401(k) Plan on behalf of its employees in the years ended December 31, 2021 or 2020.

Net Loss Per Share Attributable

Net Loss Per Share Attributable to Common Stockholders	12 Months Ended
	Dec. 31, 2021
Earnings Per Share [Abstract]
Net Loss Per Share Attributable to Common Stockholders	10. Net Loss Per Share Attributable to Common Stockholders Basic and diluted net loss per common share is calculated as follows (in thousands except share and per share amounts): Year Ended December 31, 2021 2020 Net loss $ (35,821 ) $ (27,531 ) Cumulative dividends on convertible preferred stock — (7,189 ) Net loss attributable to common stockholders $ (35,821 ) $ (34,720 ) Net loss per common share—basic and diluted $ (1.69 ) $ (5.25 ) Weighted-average number of shares used in computing net loss per common share—basic and diluted 21,199,291 6,618,445 The following outstanding potentially dilutive shares have been excluded from the calculation of diluted net loss per share due to their anti-dilutive effect: As of December 31, 2021 2020 Stock options to purchase common stock 3,777,398 2,756,102 Restricted stock units 969,700 80,000 Warrants to purchase common stock 27,759 27,759

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America, or GAAP, and stated in U.S. dollars. Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification, or ASC, and Accounting Standards Updates, or ASUs, of the Financial Accounting Standards Board, or FASB.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with GAAP requires the Company to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statements and reported amounts of expenses during the reporting periods. Actual results could differ from those estimates. On an ongoing basis, the Company evaluates its estimates, including those related to accrued research and development expenses, contingent milestone payments, other long-lived assets, stock-based compensation , and the valuation of deferred tax assets . The Company bases its estimates using historical experience, Company forecasts and future plans, current economic conditions, and information from third-party professionals that management believes to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets and liabilities and recorded amounts of expenses that are not readily apparent from other sources , and adjusts those estimates and assumptions when facts and circumstances dictate. The Company’s results can also be affected by economic, political, legislative, regulatory and legal actions. Economic conditions, such as recessionary trends, inflation, interest, changes in regulatory laws and monetary exchange rates, and government fiscal policies, can have a significant effect on operations. While the Company maintains reserves for anticipated liabilities, the Company could be adversely affected by civil, criminal, regulatory or administrative actions, claims, or related proceedings.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid investments with original maturities at the date of purchase of three months or less to be cash equivalents. Cash and cash equivalents are stated at fair value and may include
Investments	Investments The Company invests its excess cash balances in marketable government agency bonds, corporate debt securities and commercial paper. The Company classifies its investments as available-for-sale, reports available-for-sale investments at their fair value at each balance sheet date, and includes any unrealized holding gains and losses (the adjustment to fair value) in accumulated other comprehensive loss, a component of stockholders’ equity. Should there be any realized gains or losses, they will be determined using the specific-identification method and included as other income or expense in the statements of operations. The Company periodically evaluates whether declines in fair values of its marketable securities below their book value are other-than-temporary. This evaluation consists of several qualitative and quantitative factors regarding the severity and duration of the unrealized loss as well as the Company’s ability and intent to hold the marketable security until a forecasted recovery occurs. Additionally, the Company assesses whether it has plans to sell the security or it is more likely than not it will be required to sell any marketable securities before recovery of its amortized cost basis. Impairment assessments are made at the individual security level each reporting period. When the fair value of an available-for-sale security is less than its cost at the balance sheet date, a determination is made as to whether the impairment is other-than-temporary and, if it is other-than-temporary, an impairment loss is recognized in the statements of operations, equal to the difference between the investment’s amortized cost and fair value at such date. The Company did not record any impairment charges related to its marketable securities during the years ended December 31, 2021 and 2020. The Company classifies its available-for-sale marketable securities as non-current if such instrument’s underlying effective maturity date exceeds 12 months and for which the Company has the intent and ability to hold the investment for a period of greater than 12 months. The Company’s marketable securities at December 31, 2021 and 2020 mature in less than 12 months and are included in short-term investments in the balance sheets.
Concentrations of Credit Risk and Off-balance Sheet Risk	Concentrations of Credit Risk and Off-balance Sheet Risk Financial instruments that potentially subject the Company to a concentration of credit risk consist primarily of cash and cash equivalents and available-for-sale marketable securities. The Company’s investment policy includes guidelines regarding the quality of the financial institutions and financial instruments and defines allowable investments that the Company believes minimizes the exposure to concentration of credit risk. The Company may invest in money market funds, U.S. Treasury securities, corporate debt, U.S. government-related agency securities, commercial paper and certificates of deposit. At December 31, 2021 and 2020, the Company’s cash and cash equivalents were held in financial institutions that management believes are creditworthy. These deposits may exceed federally insured limits. The Company has not experienced any losses historically in these accounts and believes it is not exposed to significant credit risk in its cash and cash equivalents. The Company has no significant off-balance sheet concentrations of credit risk, such as foreign currency exchange contracts, option contracts, or other hedging arrangements.
Property and Equipment	Property and Equipment Property and equipment are stated at cost, subject to adjustments for impairments, less accumulated depreciation and amortization. Depreciation is calculated using the straight-line method over the useful lives of the assets as follows: Asset Estimated useful life Manufacturing and laboratory equipment Three to five years Computer hardware Three to five years Office furniture and equipment Three to five years Leasehold improvements are amortized over the shorter of their useful lives or the related lease term. Maintenance and repairs that do not improve or extend the life of the respective asset are expensed to operations as incurred. Manufacturing and laboratory equipment received is classified as construction in progress until placed into service, at which time depreciation commences. Upon disposal of an asset, the related cost and accumulated depreciation are removed from the accounts and any resulting gain or loss is included in the results of operations.
Impairment of Long-lived Assets	Impairment of Long-lived Assets The Company evaluates whether current facts or circumstances indicate that the carrying values of its long-lived assets may not be recoverable. If such facts or circumstances are determined to exist, an estimate of the sum of the undiscounted future cash flows of these assets is compared to the carrying value the assets to determine whether impairment exists. If the assets are determined to be impaired, the loss is measured based on the difference between the sum of the undiscounted future cash flows and the carrying value of the assets. No impairment losses were recorded during the years ended December 31, 2021 or 2020.
Research and Development Expenses	Research and Development Expenses Research and development costs are expensed as incurred. The Company’s research and development expenses consist primarily of costs incurred for the development of its product candidates and include expenses incurred under agreements with contract manufacturing organizations, or CMOs, contract research organizations, or CROs, investigative sites and consultants to conduct clinical trials and preclinical and non-clinical studies, costs to acquire, develop and manufacture supplies for clinical trials and other studies, salaries and related costs, including stock-based compensation, depreciation and other allocated facility-related and overhead expenses.
Accrued Research and Development Costs	Accrued Research and Development Costs The Company records accruals for estimated costs of preclinical and clinical studies and manufacturing development. The Company’s clinical and manufacturing development activities are conducted by third-party service providers, including CROs and CMOs. The financial terms of these contracts are subject to negotiation, which vary by contract and may result in payments that do not match the periods over which materials or services are provided. The Company accrues the costs incurred under the agreements based on an estimate of actual work completed in accordance with the agreements. In the event the Company makes advance payments for goods or services that will be used or rendered for future research and development activities, the payments are deferred and capitalized as a prepaid expense and recognized as expense as the goods are received or the related services are rendered. Such payments are evaluated for current or non-current classification based on when they are expected to be realized. If the Company does not identify costs that have begun to be incurred or if the Company underestimates or overestimates the level of services performed or the costs of these services, actual expenses could differ from the Company’s estimates. To date, the Company has not experienced significant changes in its estimates of preclinical studies, clinical trial and manufacturing accruals.
Patents Costs	Patent Costs Costs to secure and maintain patents covering the Company’s technology and product candidates are expensed as incurred and are classified as general and administrative expenses in the statements of operations.
Convertible Preferred Stock	Convertible Preferred Stock The Company classified convertible preferred stock outside of stockholders’ equity (deficit) on its balance sheet as of December 31, 2019, as the requirements of triggering a deemed liquidation event were not within the Company’s control. In the event of a deemed liquidation event, the proceeds from the event would have been distributed in accordance with liquidation preferences of such securities. The Company would have adjusted the carrying value of the convertible preferred stock to their redemption values when it became probable a redemption event would occur. Prior to the completion of the IPO on September 24, 2020, all of the outstanding shares of convertible preferred stock automatically converted into 13,085,913 shares of common stock. Subsequent to the closing of the IPO on September 29, 2020, there were no shares of convertible preferred stock outstanding .
Preferred Stock Tranche Obligation	Preferred Stock Tranche Obligation The Company’s Series C convertible preferred stock included features the Company determined were not clearly and closely related to the equity host. These features were therefore bifurcated and accounted for separately as a freestanding derivative liability on the balance sheet at its estimated fair value. This derivative liability was a result of certain investors’ rights to purchase from the Company, on the same terms as the Series C Preferred Stock Purchase Agreement executed in July 2019, additional shares of Series C convertible preferred stock in subsequent tranches based on the achievement of certain development milestones, or the Preferred Stock Tranche Obligation. At initial recognition, the Company recorded this derivative as a liability on the balance sheet at its estimated fair value. The derivative was subject to remeasurement at each balance sheet date until its expiration in September 2020, with changes in fair value recognized in change in fair value of Preferred Stock Tranche Obligation on the Company’s statements of operations.
Stock-based Compensation	Stock-based Compensation Stock-based compensation expense related to stock options and warrants granted to employees, directors and non-employees is recognized based on the grant-date estimated fair values of the awards using the Black-Scholes option pricing model, or Black-Scholes. The valuation of restricted stock units, or RSUs, is determined at the date of grant using the Company’s closing stock price. The value is recognized as expense ratably over the requisite service period, which is generally the vesting term of the award. The Company adjusts the expense for actual forfeitures as they occur.
Income Taxes	Income Taxes The Company uses the liability method to account for income taxes. Under this method, deferred tax assets and liabilities are determined based on temporary differences between the financial statement carrying amounts of existing assets and liabilities and their tax bases. Deferred tax assets and liabilities are measured using enacted tax rates applied to taxable income in the years in which those temporary differences are expected to be recovered or settled. A valuation allowance is established when necessary to reduce deferred tax assets to the amount expected to be realized. The Company assesses the likelihood of deferred tax assets being realized. A valuation allowance is provided when it is more likely than not that some portion or all of a deferred tax asset will not be realized. For the Company, the ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the periods in which the temporary differences representing net future deductible amounts become deductible. Based on the Company’s operations to date and the uncertainty as to the timing and amount of future taxable income, the Company has recorded a full valuation allowance in all periods and for all jurisdictions. Financial statement effects of uncertain tax positions are recognized when it is more likely than not, based on the technical merits of the position, that it will be sustained upon examination. The Company evaluates uncertain tax positions on a regular basis. The evaluations are based on a number of factors, including changes in facts and circumstances, changes in tax law, correspondence with tax authorities during the course of an audit, and effective settlement of audit issues. Interest and penalties related to unrecognized tax benefits would be included within the income tax provision.
Net Loss Per Share	Net Loss Per Share The Company calculates basic and diluted net loss per share attributable to common stockholders in conformity with the two-class method required for participating securities. While it was outstanding, the Company considered its convertible preferred stock to be participating securities as, in the event a dividend was paid on common stock, the holders of convertible preferred stock and unvested shares of common stock would have been entitled to receive dividends on a basis consistent with the common stockholders. The net loss attributable to common stockholders was not allocated to the convertible preferred stock as the holders of those securities did not have a contractual obligation to share in losses. Cumulative dividends on preferred stock were added to net loss to arrive at net loss available to common stockholders. Under the two-class method, basic net loss per share attributable to common stockholders is computed by dividing the net loss attributable to common stockholders by the weighted-average number of common shares outstanding during the period, without consideration of potential dilutive securities. Diluted net loss per share is calculated by dividing net loss by the weighted-average number of shares of common stock and potential dilutive common stock equivalents outstanding during the period if the effect is dilutive. Potentially dilutive securities include warrants, stock options, RSUs and convertible preferred stock. Likewise, adjustments to the denominator are required to reflect the related dilutive shares. In all periods presented, the Company’s outstanding stock options, RSUs, convertible preferred stock, common stock warrants, and the potential issuance of additional preferred shares from the Preferred Stock Tranche Obligation were excluded from the calculation of diluted net loss per share because their effects were antidilutive and the development milestones for the issuance of additional shares from the P referred S tock T ranche Obligation were not achieved prior to its expiration in September 2020 .
Related Party Transactions	Related Party Transactions In August 2019, the Company engaged a consulting firm managed by the then acting chief financial officer of the Company for professional services related to finance and other administrative functions. For the year ended December 31, 2020, the costs incurred under this arrangement totaled $657,000 and were recorded as general and administrative expense in the accompanying statement of operations. The Company terminated its relationship with this entity in September 2020.
Segments	Segments Operating segments are defined as components of an entity for which separate financial information is available and that is regularly reviewed by the chief operating decision maker, or CODM, in deciding how to allocate resources to an individual segment and in assessing performance. The Company’s CODM is its chief executive officer. The Company has determined it operates in one segment.
Comprehensive Loss	Comprehensive Loss Comprehensive loss is defined as the change in equity of a business enterprise during a period arising from transactions and other events and circumstances from non-owner sources. The Company’s comprehensive loss is comprised of changes in unrealized (loss) gain on available-for-sale securities.
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) In June 2016, the FASB issued ASU 2016-13, Financial Instruments-Credit Losses: Measurement of Credit Losses on Financial Instruments Codification Improvements to Topic 326, Financial Instruments-Credit Losses, Topic 815, Derivatives and Hedging and Topic 825, Financial Instruments In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Schedule of Property and Equipment and Depreciation Calculated using Straight-line Method over useful Life of Asset	Depreciation is calculated using the straight-line method over the useful lives of the assets as follows: Asset Estimated useful life Manufacturing and laboratory equipment Three to five years Computer hardware Three to five years Office furniture and equipment Three to five years Property and equipment, net, consisted of the following (in thousands): December 31, 2021 2020 Manufacturing and laboratory equipment $ 2,511 $ 2,179 Computer hardware 28 28 Office furniture and equipment 28 28 Leasehold improvement 234 234 Construction in progress 833 611 Total property and equipment, at cost 3,634 3,080 Less: accumulated depreciation (1,653 ) (1,134 ) Property and equipment, net $ 1,981 $ 1,946

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2021
Fair Value Disclosures [Abstract]
Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis	The following tables present information about the Company’s financial assets and liabilities measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values (in thousands): December 31, 2021 Level 1 Level 2 Level 3 Total Current assets: Cash equivalents: Money market funds $ 8,920 $ — $ — $ 8,920 Corporate debt securities — 1,480 — 1,480 Commercial paper — 2,749 — 2,749 Total cash equivalents 8,920 4,229 — 13,149 Short-term investments: Corporate debt securities — 1,117 — 1,117 Commercial paper — 41,954 — 41,954 U.S. Treasury notes — 7,235 — 7,235 Total short-term investments — 50,306 — 50,306 Total assets measured at fair value $ 8,920 $ 54,535 $ — $ 63,455 December 31, 2020 Level 1 Level 2 Level 3 Total Current assets: Cash equivalents: Money market funds $ 15,677 $ — $ — $ 15,677 Corporate debt securities — 2,500 — 2,500 Commercial paper — 13,499 — 13,499 Total cash equivalents 15,677 15,999 — 31,676 Short-term investments: Corporate debt securities — 11,588 — 11,588 Commercial paper — 50,027 — 50,027 Total short-term investments — 61,615 — 61,615 Total assets measured at fair value $ 15,677 $ 77,614 $ — $ 93,291
Summary of Company's Financial Assets Measured at Fair Value	The following tables present information as to cost, unrealized gains and losses and fair value determination of the Company’s financial assets measured at fair value on a recurring basis (in thousands): December 31, 2021 Amortized Cost Unrealized Gains Unrealized Losses Aggregate Fair Value Current assets: Cash equivalents: Money market funds $ 8,920 $ — $ — $ 8,920 Corporate debt securities 1,480 — — 1,480 Commercial paper 2,749 — — 2,749 Total cash equivalents 13,149 — — 13,149 Short-term investments: Corporate debt securities 1,117 — (1 ) 1,116 Commercial paper 41,956 6 (8 ) 41,954 U.S. Treasury notes 7,249 — (13 ) 7,236 Total short-term investments 50,322 6 (22 ) 50,306 Total assets measured at fair value $ 63,471 $ 6 $ (22 ) $ 63,455 December 31, 2020 Amortized Cost Unrealized Gains Unrealized Losses Aggregate Fair Value Current assets: Cash equivalents: Money market funds $ 15,677 $ — $ — $ 15,677 Corporate debt securities 2,502 — (2 ) 2,500 Commercial paper 13,498 1 — 13,499 Total cash equivalents 31,677 1 (2 ) 31,676 Short-term investments: Corporate debt securities 11,588 1 (1 ) 11,588 Commercial paper 50,030 2 (5 ) 50,027 Total short-term investments 61,618 3 (6 ) 61,615 Total assets measured at fair value $ 93,295 $ 4 $ (8 ) $ 93,291

Balance Sheet Components (Table

Balance Sheet Components (Tables)	12 Months Ended
	Dec. 31, 2021
Balance Sheet Related Disclosures [Abstract]
Schedule of Property and Equipment and Depreciation Calculated using Straight-line Method over useful Life of Asset	Depreciation is calculated using the straight-line method over the useful lives of the assets as follows: Asset Estimated useful life Manufacturing and laboratory equipment Three to five years Computer hardware Three to five years Office furniture and equipment Three to five years Property and equipment, net, consisted of the following (in thousands): December 31, 2021 2020 Manufacturing and laboratory equipment $ 2,511 $ 2,179 Computer hardware 28 28 Office furniture and equipment 28 28 Leasehold improvement 234 234 Construction in progress 833 611 Total property and equipment, at cost 3,634 3,080 Less: accumulated depreciation (1,653 ) (1,134 ) Property and equipment, net $ 1,981 $ 1,946
Schedule of Prepaid Expenses and Other Current Assets	Prepaid expenses and other current assets consisted of the following (in thousands): December 31, 2021 2020 Prepaid expenses $ 1,866 $ 2,140 Prepaid clinical and research expenses 168 6 Interest and other receivables 21 598 Other current assets 1,353 1,463 Total prepaid expenses and other current assets $ 3,408 $ 4,207
Schedule of Other Current Liabilities	Other current liabilities consisted of the following (in thousands): December 31, 2021 2020 Salaries and benefits $ 2,278 $ 2,302 Professional services 461 425 Deferred rent 8 27 Other 479 374 Total other current liabilities $ 3,226 $ 3,128

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2021
Commitments And Contingencies Disclosure [Abstract]
Schedule of Future Minimum Lease Payments	Future minimum lease payments under the Company’s non–cancelable operating leases as of December 31, 2021 were as follows (in thousands): Year ended December 31: 2022 $ 527 2023 205 Total future minimum lease payments $ 732
Schedule of Expense under JHU Agreement	Expense under the JHU Agreement is as follows (in thousands): Year Ended December 31, 2021 2020 Research and development $ 38 $ 38 General and administrative 160 165 Total JHU Agreement expense $ 198 $ 203

Convertible Preferred Stock a_2

Convertible Preferred Stock and Preferred Stock Tranche Obligation (Tables)	12 Months Ended
	Dec. 31, 2021
Temporary Equity Disclosure [Abstract]
Summary of Outstanding Convertible Preferred Stock	The following table summarizes outstanding convertible preferred stock as of December 31, 2019 (in thousands, except share amounts): Shares Authorized Shares Outstanding Net Carrying Value Liquidation Preference Series A 2,280,000 2,280,000 $ 2,280 $ 2,280 Series A-2 2,018,561 2,018,561 1,605 1,740 Series B 76,078,535 76,078,535 74,926 87,729 Series C 61,773,000 37,432,787 52,552 56,843 Total 142,150,096 117,809,883 $ 131,363 $ 148,592

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Stock Option Activity	The following summarizes stock option activity: Weighted Weighted Average Average Remaining Aggregate Number of Exercise Contractual Intrinsic Options Price Term Value (In years) (In thousands) Outstanding—December 31, 2020 2,756,102 $ 8.28 8.6 $ 57,090 Granted 1,649,500 $ 3.74 Exercised (353,508 ) $ 1.97 Forfeited and Canceled (274,696 ) $ 12.52 Outstanding—December 31, 2021 3,777,398 $ 6.58 8.4 $ 41,967 Options Exercisable—December 31, 2021 1,705,619 $ 5.24 7.4 $ 41,967
Summary of Restricted Stock Units (RSUs) Activity	The following table summarizes restricted stock units (RSUs) activity for the year ended December 31, 2021: RSUs Outstanding Number of Restricted Stock Units Weighted-Average Grant Date Fair Value Per Share Balance - December 31, 2020 80,000 $ 16.50 Granted 988,700 $ 3.73 Vested (25,000 ) $ 16.50 Cancelled/forfeited (74,000 ) $ 3.74 Balance - December 31, 2021 969,700 $ 4.45
Schedule of Assumptions Using Black-Scholes to Estimate Fair Value of Each Awards	The fair value of each award is estimated using Black-Scholes based on the following assumptions: Year Ended December 31, 2021 2020 Expected term (years) 5.1-6.1 5.0-6.1 Expected volatility 87% - 88% 85% Risk-free interest rate 0.84%-1.12% 0.25%-0.53% Expected dividend — —
Summary of Stock-Based Compensation Expense	Stock-based compensation expense is classified as follows (in thousands): Year Ended December 31, 2021 2020 Research and development $ 1,210 $ 390 General and administrative 4,165 1,398 Total stock-based compensation expense $ 5,375 $ 1,788

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Schedule of Reconciliation of Federal Statutory Income Tax Rate to Effective Income Tax Rate	The reconciliation of the federal statutory income tax rate to the Company’s effective income tax rate is as follows: Year Ended December 31, 2021 2020 Income tax benefit at the federal statutory rate 21.0 % 21.0 % State income taxes, net of federal benefit 0.6 3.2 Research and development tax credits 1.4 1.3 Other (0.4 ) (0.6 ) Mark to market gain/loss — 1.7 Change in valuation allowance (22.6 ) (26.6 ) Total — % — %
Schedule of Components of Deferred Tax Assets	The principal components of the Company’s net deferred tax assets consisted of the following (in thousands): December 31, 2021 2020 Deferred tax assets Federal and state net operating loss carryforwards $ 34,431 $ 27,567 Research and development tax credits 5,408 4,887 Other 1,408 748 Gross deferred tax assets 41,247 33,202 Less: valuation allowance (41,215 ) (33,141 ) Total deferred tax assets 32 61 Deferred tax liabilities Depreciation (32 ) (61 ) Total deferred tax liabilities (32 ) (61 ) Net deferred tax assets $ — $ —
Schedule of Reconciliation of Unrecognized Tax Benefits	A reconciliation of the unrecognized tax benefit is as follows (in thousands): Year Ended December 31, 2021 2020 Balance—beginning of year $ 1,981 $ 1,406 Addition based on tax position related to current year 257 406 (Reduction) addition based on tax position related to prior year (148 ) 169 Balance—end of year $ 2,090 $ 1,981

Net Loss Per Share Attributab_2

Net Loss Per Share Attributable to Common Stockholders (Tables)	12 Months Ended
	Dec. 31, 2021
Earnings Per Share [Abstract]
Schedule of Basic and Diluted Net Loss Per Common Share	Basic and diluted net loss per common share is calculated as follows (in thousands except share and per share amounts): Year Ended December 31, 2021 2020 Net loss $ (35,821 ) $ (27,531 ) Cumulative dividends on convertible preferred stock — (7,189 ) Net loss attributable to common stockholders $ (35,821 ) $ (34,720 ) Net loss per common share—basic and diluted $ (1.69 ) $ (5.25 ) Weighted-average number of shares used in computing net loss per common share—basic and diluted 21,199,291 6,618,445
Schedule of Anti-dilutive Securities Excluded from Calculation of Diluted Net Loss Per Share	The following outstanding potentially dilutive shares have been excluded from the calculation of diluted net loss per share due to their anti-dilutive effect: As of December 31, 2021 2020 Stock options to purchase common stock 3,777,398 2,756,102 Restricted stock units 969,700 80,000 Warrants to purchase common stock 27,759 27,759

Organization - Additional Infor

Organization - Additional Information (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Accumulated deficit	$ 169,188	$ 133,367

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Schedule of Depreciation Calculated using Straight-line Method over useful Life of Asset (Details)	12 Months Ended
	Dec. 31, 2021
Manufacturing and Laboratory Equipment | Minimum
Property Plant And Equipment [Line Items]
Property and equipment useful life of asset	3 years
Manufacturing and Laboratory Equipment | Maximum
Property Plant And Equipment [Line Items]
Property and equipment useful life of asset	5 years
Computer Hardware | Minimum
Property Plant And Equipment [Line Items]
Property and equipment useful life of asset	3 years
Computer Hardware | Maximum
Property Plant And Equipment [Line Items]
Property and equipment useful life of asset	5 years
Office Furniture and Equipment | Minimum
Property Plant And Equipment [Line Items]
Property and equipment useful life of asset	3 years
Office Furniture and Equipment | Maximum
Property Plant And Equipment [Line Items]
Property and equipment useful life of asset	5 years

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Additional Information (Details)	Sep. 24, 2020shares	Dec. 31, 2021USD ($)Segment	Dec. 31, 2020USD ($)	Sep. 29, 2020shares	Dec. 31, 2019shares
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Impairment losses | $		$ 0	$ 0
Shares outstanding | shares				0	117,809,883
Number of operating segment | Segment		1
Accounting Standards Update 2016-02
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Change in accounting principle, accounting standards update, adopted		true
Change in accounting principle, accounting standards update, adoption date		Jan. 1, 2022
Change in accounting principle, accounting standards update, immaterial effect		true
General and Administrative
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Related party transaction, costs incurred | $			$ 657,000
Initial Public Offering
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Conversion of convertible preferred stock into common stock upon the initial public offering, Shares | shares	13,085,913

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current assets:
Cash equivalents	$ 13,149	$ 31,676
Short-term investments	50,306	61,615
Assets measured at fair value	63,455	93,291
Money Market Funds
Current assets:
Cash equivalents	8,920	15,677
Corporate Debt Securities
Current assets:
Cash equivalents	1,480	2,500
Short-term investments	1,117	11,588
Commercial Paper
Current assets:
Cash equivalents	2,749	13,499
Short-term investments	41,954	50,027
U.S. Treasury Notes
Current assets:
Short-term investments	7,235
Level 1
Current assets:
Cash equivalents	8,920	15,677
Assets measured at fair value	8,920	15,677
Level 1 | Money Market Funds
Current assets:
Cash equivalents	8,920	15,677
Level 2
Current assets:
Cash equivalents	4,229	15,999
Short-term investments	50,306	61,615
Assets measured at fair value	54,535	77,614
Level 2 | Corporate Debt Securities
Current assets:
Cash equivalents	1,480	2,500
Short-term investments	1,117	11,588
Level 2 | Commercial Paper
Current assets:
Cash equivalents	2,749	13,499
Short-term investments	41,954	$ 50,027
Level 2 | U.S. Treasury Notes
Current assets:
Short-term investments	$ 7,235

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Company 's Financial Assets Measured at Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total cash equivalents, Aggregate Fair Value	$ 13,149	$ 31,676
Total short-term investments, Aggregate Fair Value	50,306	61,615
Total asset measured at fair value, Aggregate Fair Value	63,455	93,291
Fair Value, Recurring
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total cash equivalents, Amortized Cost	13,149	31,677
Total cash equivalents, Unrealized Gains		1
Total cash equivalents, Unrealized Losses		(2)
Total cash equivalents, Aggregate Fair Value	13,149	31,676
Total short-term investments, Amortized Cost	50,322	61,618
Total short-term investments, Unrealized Gains	6	3
Total short-term investments, Unrealized Losses	(22)	(6)
Total short-term investments, Aggregate Fair Value	50,306	61,615
Total asset measured at fair value, Amortized Cost	63,471	93,295
Total asset measured at fair value, Unrealized Gains	6	4
Total asset measured at fair value, Unrealized Losses	(22)	(8)
Total asset measured at fair value, Aggregate Fair Value	63,455	93,291
Fair Value, Recurring | Money Market Funds
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total cash equivalents, Amortized Cost	8,920	15,677
Total cash equivalents, Aggregate Fair Value	8,920	15,677
Fair Value, Recurring | Corporate Debt Securities
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total cash equivalents, Amortized Cost	1,480	2,502
Total cash equivalents, Unrealized Losses		(2)
Total cash equivalents, Aggregate Fair Value	1,480	2,500
Total short-term investments, Amortized Cost	1,117	11,588
Total short-term investments, Unrealized Gains		1
Total short-term investments, Unrealized Losses	(1)	(1)
Total short-term investments, Aggregate Fair Value	1,116	11,588
Fair Value, Recurring | Commercial Paper
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total cash equivalents, Amortized Cost	2,749	13,498
Total cash equivalents, Unrealized Gains		1
Total cash equivalents, Aggregate Fair Value	2,749	13,499
Total short-term investments, Amortized Cost	41,956	50,030
Total short-term investments, Unrealized Gains	6	2
Total short-term investments, Unrealized Losses	(8)	(5)
Total short-term investments, Aggregate Fair Value	41,954	$ 50,027
Fair Value, Recurring | U.S. Treasury Notes
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total short-term investments, Amortized Cost	7,249
Total short-term investments, Unrealized Losses	(13)
Total short-term investments, Aggregate Fair Value	$ 7,236

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Other-than-temporary impairment losses	$ 0	$ 0
Fair value assets, level 1 to level 2 transfers, amount	0
Fair value assets, level 2 to level 1 transfers, amount	0
Fair value assets, transfers into level 3	0
Fair value liabilities, level 1 to Level 2 transfers amount	0
Fair value liabilities, level 2 to Level 1 transfers amount	0
Fair value liabilities, transfers into level 3	$ 0

Balance Sheet Components - Sche

Balance Sheet Components - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property Plant And Equipment [Line Items]
Property and equipment, at cost	$ 3,634	$ 3,080
Less: accumulated depreciation	(1,653)	(1,134)
Property and equipment, net	1,981	1,946
Manufacturing and Laboratory Equipment
Property Plant And Equipment [Line Items]
Property and equipment, at cost	2,511	2,179
Computer Hardware
Property Plant And Equipment [Line Items]
Property and equipment, at cost	28	28
Office Furniture and Equipment
Property Plant And Equipment [Line Items]
Property and equipment, at cost	28	28
Leasehold Improvement
Property Plant And Equipment [Line Items]
Property and equipment, at cost	234	234
Construction in Progress
Property Plant And Equipment [Line Items]
Property and equipment, at cost	$ 833	$ 611

Balance Sheet Components - Addi

Balance Sheet Components - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Property Plant And Equipment [Abstract]
Depreciation expense	$ 519	$ 395

Balance Sheet Components - Sc_2

Balance Sheet Components - Schedule of Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Prepaid Expense And Other Assets Current [Abstract]
Prepaid expenses	$ 1,866	$ 2,140
Prepaid clinical and research expenses	168	6
Interest and other receivables	21	598
Other current assets	1,353	1,463
Total prepaid expenses and other current assets	$ 3,408	$ 4,207

Balance Sheet Components - Sc_3

Balance Sheet Components - Schedule of Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Other Liabilities Current [Abstract]
Salaries and benefits	$ 2,278	$ 2,302
Professional services	461	425
Deferred rent	8	27
Other	479	374
Total other current liabilities	$ 3,226	$ 3,128

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details)	Mar. 10, 2022USD ($)	Jul. 29, 2021USD ($)ft²	Sep. 30, 2015USD ($)	Oct. 31, 2014USD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020USD ($)
Loss Contingencies [Line Items]
Contract termination commitment					$ 3,700,000
Unpaid cancellation and other related costs					0
Rent expense					700,000	$ 700,000
Operating expenses					35,947,000	29,832,000
Accounts payable					527,000	2,513,000
JHU
Loss Contingencies [Line Items]
Operating expenses					198,000	203,000
License Agreement | JHU
Loss Contingencies [Line Items]
One-time, non-refundable fee			$ 100,000
Maximum credit percentage of running royalty rate			50.00%
Kala Agreement
Loss Contingencies [Line Items]
Percentage of minimum annual royalties including development milestone payments for first licensed product				25.00%
Development milestone payment extension period				1 year
Development milestone payable under second licensed product				$ 100,000
Development milestone payable under third licensed product				$ 150,000
Operating expenses					0	0
Accounts payable					0	0
AffaMed Letter
Loss Contingencies [Line Items]
Operating expenses					0	0
Accounts payable					$ 0	0
Option expiration period					Jul. 31, 2021
Mireca Medicines GmbH
Loss Contingencies [Line Items]
Upfront cash payment made					$ 500,000
Additional contingent payments upon achievement of certain development and regulatory milestone					27,000,000
Development or regulatory milestones were deemed probable of achievement					0
Contingent payments recognized					$ 0
Private Company | Subsequent Event
Loss Contingencies [Line Items]
Additional contingent payments upon achievement of certain development and regulatory milestone	$ 20,000,000
Private company purchase cost including estimated transaction costs and contingent holdback	$ 2,000,000
Baltimore, Maryland
Loss Contingencies [Line Items]
Operating lease, term					2023-06
Redwood City, California
Loss Contingencies [Line Items]
Area of office space | ft²		2,560
Lessee operating lease commencement date		Aug. 18, 2021
Lessee, operating lease, term of contract		12 months
Lessee operating lease expiration date		Aug. 31, 2022			Aug. 31, 2021
Total lease obligation over the term of the lease		$ 200,000
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]		Other current liabilities
Payment of security deposit and rent upon execution of lease		$ 31,000
United States | Kala Agreement
Loss Contingencies [Line Items]
Percentage of commercial milestone payments reduced				50.00%
Operating Expense
Loss Contingencies [Line Items]
Other commitments and cancellation fees					$ 900,000
Research and Development | JHU
Loss Contingencies [Line Items]
Operating expenses					38,000	$ 38,000
Research and Development | Mireca Medicines GmbH
Loss Contingencies [Line Items]
Upfront cash payment made					500,000
Minimum | License Agreement | JHU
Loss Contingencies [Line Items]
Percentage of royalty payments on net sales			50.00%
Percentage of developmental milestone payment for second and third products			50.00%
Maximum | License Agreement | JHU
Loss Contingencies [Line Items]
Aggregate total amount of developmental milestone payment			$ 2,000,000
Research and Development
Loss Contingencies [Line Items]
Contractual obligation					$ 800,000
Research and Development | Minimum
Loss Contingencies [Line Items]
Contractual obligation term					3 months
Research and Development | Maximum
Loss Contingencies [Line Items]
Contractual obligation term					15 months
General and Administrative
Loss Contingencies [Line Items]
Commitment expenses recognized					$ 2,200,000
Fixed Asset Purchase Agreements
Loss Contingencies [Line Items]
Write off of deposits					$ 1,300,000

Commitments and Contingencies_2

Commitments and Contingencies - Schedule of Future Minimum Lease Payments (Details) $ in Thousands	Dec. 31, 2021USD ($)
Commitments And Contingencies Disclosure [Abstract]
2022	$ 527
2023	205
Total future minimum lease payments	$ 732

Commitments and Contingencies_3

Commitments and Contingencies - Schedule of Expense under JHU Agreement (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Loss Contingencies [Line Items]
Total JHU Agreement expense	$ 35,947	$ 29,832
JHU
Loss Contingencies [Line Items]
Total JHU Agreement expense	198	203
Research and Development | JHU
Loss Contingencies [Line Items]
Total JHU Agreement expense	38	38
General and Administrative | JHU
Loss Contingencies [Line Items]
Total JHU Agreement expense	$ 160	$ 165

Convertible Preferred Stock a_3

Convertible Preferred Stock and Preferred Stock Tranche Obligation - Summary of Outstanding Convertible Preferred Stock (Details) - USD ($) $ in Thousands	Sep. 29, 2020	Dec. 31, 2019	Jul. 31, 2019
Temporary Equity [Line Items]
Shares Authorized		142,150,096
Shares outstanding	0	117,809,883
Net Carrying Value		$ 131,363
Liquidation Preference		$ 148,592
Series A
Temporary Equity [Line Items]
Shares Authorized		2,280,000
Shares outstanding		2,280,000
Net Carrying Value		$ 2,280
Liquidation Preference		$ 2,280
Series A-2
Temporary Equity [Line Items]
Shares Authorized		2,018,561
Shares outstanding		2,018,561
Net Carrying Value		$ 1,605
Liquidation Preference		$ 1,740
Series B
Temporary Equity [Line Items]
Shares Authorized		76,078,535
Shares outstanding		76,078,535
Net Carrying Value		$ 74,926
Liquidation Preference		$ 87,729
Series C
Temporary Equity [Line Items]
Shares Authorized		61,773,000	61,773,000
Shares outstanding		37,432,787
Net Carrying Value		$ 52,552
Liquidation Preference		$ 56,843

Convertible Preferred Stock a_4

Convertible Preferred Stock and Preferred Stock Tranche Obligation - Additional Information (Details) $ / shares in Units, $ in Millions	Sep. 24, 2020shares	Jul. 31, 2019USD ($)$ / sharesshares	Aug. 31, 2019USD ($)shares	Dec. 31, 2021USD ($)$ / shares	Dec. 31, 2020USD ($)	Sep. 29, 2020shares	Dec. 31, 2019shares
Temporary Equity [Line Items]
Shares Authorized							142,150,096
Shares outstanding						0	117,809,883
Preferred stock voting rights				The holders of Series C Preferred are entitled to elect one director of the Company; the holders of Series B Preferred are entitled to elect three directors of the Company; the holders of Series A-2 Preferred, are entitled to elect one director; the holders of common stock are entitled to elect one director; and holders of common stock and any other class or series of voting stock, exclusively and voting together as a single class on an as-converted basis, are entitled to elect one director. Holders of Series A Preferred are not entitled to a director of the Company.
Common stock, voting rights				one
Initial Public Offering
Temporary Equity [Line Items]
Conversion of convertible preferred stock into common stock upon the initial public offering, Shares	13,085,913
Series C Convertible Preferred Stock
Temporary Equity [Line Items]
Shares Authorized		61,773,000					61,773,000
Convertible preferred stock, price per share | $ / shares		$ 1.4693
Convertible preferred stock, shares issued			37,432,787
Gross proceeds from issue of convertible preferred stock | $			$ 55
Convertible preferred stock, price per share | $ / shares		$ 1.4693
Gain on change in fair value of preferred stock tranche obligation | $					$ 2.2
Shares outstanding							37,432,787
Dividends rights, amount per share on each outstanding share payable | $ / shares				$ 0.117544
Convertible preferred stock, price per share | $ / shares				$ 1.4693
Preferred stock voting rights				one
Series C Convertible Preferred Stock | Current Liability
Temporary Equity [Line Items]
Fair value of preferred stock tranche obligation | $		$ 2.2
Series B Preferred
Temporary Equity [Line Items]
Shares Authorized							76,078,535
Shares outstanding							76,078,535
Dividends rights, amount per share on each outstanding share payable | $ / shares				$ 0.06937
Convertible preferred stock, price per share | $ / shares				$ 0.991
Preferred stock voting rights				three
Series A-2
Temporary Equity [Line Items]
Shares Authorized							2,018,561
Shares outstanding							2,018,561
Dividends rights, amount per share on each outstanding share payable | $ / shares				$ 0.06034
Convertible preferred stock, price per share | $ / shares				$ 0.862
Preferred stock voting rights				one
Series A
Temporary Equity [Line Items]
Shares Authorized							2,280,000
Shares outstanding							2,280,000
Dividends rights, amount per share on each outstanding share payable | $ / shares				$ 0.08
Preferred stock, convertible, conversion price				8.8527
Convertible preferred stock, price per share | $ / shares				$ 1
Series C Preferred, Series B Preferred and Series A-2 Preferred
Temporary Equity [Line Items]
Preferred stock, convertible, conversion price				9.0058
Series A-2 Preferred, Series B Preferred and Series C Preferred
Temporary Equity [Line Items]
Preferred stock voting rights				Shares of Series A-2 Preferred, Series B Preferred and Series C Preferred do not have voting rights.
Maximum | Series C Convertible Preferred Stock
Temporary Equity [Line Items]
Convertible preferred stock option to purchase additional shares		17,014,902
Convertible preferred stock option to purchase additional shares after notified, period		30 days
Minimum
Temporary Equity [Line Items]
Convertible preferred stock, price per share | $ / shares				$ 14.56
Gross proceeds from issue of convertible preferred stock | $				$ 40

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Details)	Jan. 14, 2022Employee$ / sharesshares	Aug. 31, 2020shares	Dec. 31, 2021USD ($)$ / sharesshares	Dec. 31, 2020USD ($)$ / sharesshares	Jan. 01, 2021shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Aggregate number of shares issued			21,357,773	20,979,265
Options granted			1,649,500
Common stock at an exercise price | $ / shares			$ 3.74
Aggregate intrinsic value of options exercised | $			$ 2,500,000	$ 113,000
Aggregate fair value of options vested | $			$ 4,000,000	$ 1,400,000
Weighted average grant date fair value per share of options vested | $ / shares			$ 6.06	$ 2.43
Weighted-average grant date fair value per option granted | $ / shares			$ 2.72	$ 11.90
Total unrecognized stock-based compensation expenses related to outstanding unvested stock awards | $			$ 15,400,000
Total unrecognized stock-based compensation expenses related to outstanding unvested stock options weighted-average term of recognition			2 years 9 months 18 days
RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Aggregate fair value of RSUs vested | $			$ 400,000
Share-based compensation arrangement by share-based payment award, equity instruments other than options, vested			25,000	0
2020 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares reserved for future issuance		1,850,000	445,617
Percentage of aggregate number of shares of common stock outstanding on last day of preceding year added to plan		5.00%
Number of additional awards grant		0
Common stock additional aggregate number of shares reserved					1,048,963
2020 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares reserved for future issuance		210,000
Percentage of aggregate number of shares of common stock outstanding on last day of preceding year added to plan		1.00%
Aggregate number of shares issued			2,100,000
Inducement Grants
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of newly hired employees | Employee	6
Options granted	234,200
Common stock at an exercise price | $ / shares	$ 1.55
Vesting percentage on first year anniversary	0.25%
Description of vesting rights	One-fourth of the options will vest on the one-year anniversary of the vesting commencement date and the remainder will vest in equal monthly installments over the next three years, in each case subject to the new employee’s continued service with the Company.
Stock options term	10 years

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Stock Option Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Number of Options, Outstanding	2,756,102
Number of Options, Granted	1,649,500
Number of Options, Exercised	(353,508)
Forfeited and Canceled	(274,696)
Number of Options, Outstanding	3,777,398	2,756,102
Number of Options, Options Exercisable	1,705,619
Weighted Average Exercise Price, Outstanding	$ 8.28
Weighted Average Exercise Price, Granted	3.74
Weighted Average Exercise Price, Exercised	1.97
Forfeited and Canceled	12.52
Weighted Average Exercise Price, Outstanding	6.58	$ 8.28
Weighted Average Exercise Price, Options Exercisable	$ 5.24
Weighted Average Remaining Contractual Term, Outstanding		8 years 4 months 24 days	8 years 7 months 6 days
Weighted Average Remaining Contractual Term, Options Exercisable		7 years 4 months 24 days
Aggregate Intrinsic Value, Outstanding	$ 41,967	$ 57,090
Aggregate Intrinsic Value, Options Exercisable	$ 41,967

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of Restricted Stock Units (Detail) - Restricted Stock Units - $ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Restricted Stock Units, Balance	80,000
Number of Restricted Stock Units, Granted	988,700
Number of Restricted Stock Units, Vested	(25,000)	0
Number of Restricted Stock Units, Cancelled/Forfeited	(74,000)
Number of Restricted Stock Units, Balance	969,700	80,000
Weighted-Average Grant Date Fair Value Per Share, Balance	$ 16.50
Weighted-Average Grant Date Fair Value Per Share, Granted	3.73
Weighted-Average Grant Date Fair Value Per Share, Vested	16.50
Weighted-Average Grant Date Fair Value Per Share, Cancelled/Forfeited	3.74
Weighted-Average Grant Date Fair Value Per Share, Balance	$ 4.45	$ 16.50

Stock-Based Compensation - Sche

Stock-Based Compensation - Schedule of Assumptions Using Black-Scholes to Estimate Fair Value of Each Awards (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected volatility, minimum	87.00%
Expected volatility		85.00%
Expected volatility, maximum	88.00%
Risk-free interest rate, minimum	0.84%	0.25%
Risk-free interest rate, maximum	1.12%	0.53%
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (years)	5 years 1 month 6 days	5 years
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (years)	6 years 1 month 6 days	6 years 1 month 6 days

Stock-Based Compensation - Su_3

Stock-Based Compensation - Summary of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation expense	$ 5,375	$ 1,788
Research and Development
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation expense	1,210	390
General and Administrative
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation expense	$ 4,165	$ 1,398

Income Taxes - Schedule of Reco

Income Taxes - Schedule of Reconciliation of Federal Statutory Income Tax Rate to Effective Income Tax Rate (Detail)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Income Taxes [Abstract]
Income tax benefit at the federal statutory rate	21.00%	21.00%
State income taxes, net of federal benefit	0.60%	3.20%
Research and development tax credits	1.40%	1.30%
Other	(0.40%)	(0.60%)
Mark to market gain/loss		1.70%
Change in valuation allowance	(22.60%)	(26.60%)

Income Taxes - Schedule of Comp

Income Taxes - Schedule of Components of Deferred Tax Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deferred tax assets
Federal and state net operating loss carryforwards	$ 34,431	$ 27,567
Research and development tax credits	5,408	4,887
Other	1,408	748
Gross deferred tax assets	41,247	33,202
Less: valuation allowance	(41,215)	(33,141)
Total deferred tax assets	32	61
Deferred tax liabilities
Depreciation	(32)	(61)
Total deferred tax liabilities	$ (32)	$ (61)

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Income Taxes [Line Items]
Deferred tax assets increase in valuation allowance	$ 8,100
Federal net operating loss carryforwards	157,400
State NOLs	23,300
Accrued interest and penalties related to unrecognized tax benefits	0	$ 0
Federal
Income Taxes [Line Items]
Tax credits	$ 6,100
Operating loss carryforwards expiration beginning year	2035
Tax credit carryforwards expiration beginning year	2036
Net operating loss carryforwards, infinite life	$ 123,300
State
Income Taxes [Line Items]
Tax credits	$ 1,800
Tax credit carryforwards expiration beginning year	2036

Income Taxes - Schedule of Re_2

Income Taxes - Schedule of Reconciliation of Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Income Taxes [Abstract]
Balance—beginning of year	$ 1,981	$ 1,406
Addition based on tax position related to current year	257	406
(Reduction) addition based on tax position related to prior year	(148)	169
Balance—end of year	$ 2,090	$ 1,981

Employee Retirement Plan - Addi

Employee Retirement Plan - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Compensation And Retirement Disclosure [Abstract]
Contributions by employer	$ 0	$ 0

Net Loss Per Share Attributab_3

Net Loss Per Share Attributable to Common Stockholders - Schedule of Basic and Diluted Net Loss Per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Earnings Per Share [Abstract]
Net loss	$ (35,821)	$ (27,531)
Cumulative dividends on convertible preferred stock		(7,189)
Net loss attributable to common stockholders	$ (35,821)	$ (34,720)
Net loss per common share—basic and diluted	$ (1.69)	$ (5.25)
Weighted-average number of shares outstanding used in computing net loss per common share—basic and diluted	21,199,291	6,618,445

Net Loss Per Share Attributab_4

Net Loss Per Share Attributable to Common Stockholders - Schedule of Anti-dilutive Securities Excluded from Calculation of Diluted Net Loss Per Share (Details) - shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Stock Options to Purchase Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from calculation of diluted net loss per share	3,777,398	2,756,102
Restricted Stock Units
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from calculation of diluted net loss per share	969,700	80,000
Warrants to Purchase Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from calculation of diluted net loss per share	27,759	27,759