Equillium (EQ) 10-Q 13 May 21 2021 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2021	May 10, 2021
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Entity Registrant Name	EQUILLIUM, INC.
Entity Central Index Key	0001746466
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		29,040,270
Entity Shell Company	false
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Trading Symbol	EQ
Title of 12(b) Security	Common Stock, par value $0.0001 per share
Security Exchange Name	NASDAQ
Entity File Number	001-38692
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	82-1554746
Entity Address, Address Line One	2223 Avenida de la Playa
Entity Address, Address Line Two	Suite 105
Entity Address, City or Town	La Jolla
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	92037
City Area Code	858
Local Phone Number	412-5302
Document Quarterly Report	true
Document Transition Report	false

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 50,861	$ 23,982
Short-term investments	53,218	58,181
Prepaid expenses and other current assets	2,536	3,011
Total current assets	106,615	85,174
Property and equipment, net	223	239
Other assets	0	15
Total assets	106,838	85,428
Current liabilities:
Accounts payable	2,324	2,766
Accrued expenses	2,593	2,813
Current portion of long-term notes payable	2,500	1,666
Total current liabilities	7,417	7,245
Long-term notes payable	7,506	8,275
Other non-current liabilities	35	54
Total liabilities	14,958	15,574
Commitments and contingencies
Stockholders' equity:
Common stock, $0.0001 par value; 200,000,000 shares authorized; 29,040,270 and 24,753,102 shares issued and outstanding as of March 31, 2021 and December 31, 2020, respectively	2	2
Additional paid-in capital	172,049	141,074
Accumulated other comprehensive loss	(255)	(297)
Accumulated deficit	(79,916)	(70,925)
Total stockholders' equity	91,880	69,854
Total liabilities and stockholders' equity	$ 106,838	$ 85,428

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2021	Dec. 31, 2020
Statement Of Financial Position [Abstract]
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	29,040,270	24,753,102
Common stock, shares outstanding	29,040,270	24,753,102

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Operating expenses:
Research and development	$ 5,880	$ 4,706
General and administrative	2,815	2,746
Total operating expenses	8,695	7,452
Loss from operations	(8,695)	(7,452)
Other expense, net:
Interest expense	(271)	(273)
Interest income	26	220
Other expense, net	(51)	(332)
Total other expense, net	(296)	(385)
Net loss	(8,991)	(7,837)
Other comprehensive income, net:
Unrealized (loss) gain on available-for-sale securities, net	(3)	138
Foreign currency translation gain	45	315
Total other comprehensive income, net	42	453
Comprehensive loss	$ (8,949)	$ (7,384)
Net loss per share, basic and diluted	$ (0.33)	$ (0.45)
Weighted-average common shares outstanding, basic and diluted	27,325,372	17,562,551

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Total	ATM	Common Stock	Common StockATM	Additional Paid-in Capital	Additional Paid-in CapitalATM	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Balance at Dec. 31, 2019	$ 41,848		$ 1		$ 82,938		$ 21	$ (41,112)
Balance, Shares at Dec. 31, 2019			17,425,654
Issuance of common stock	252	$ 825			252	$ 825
Issuance of common stock, Shares			83,662	174,649
Vesting of restricted stock liability	18				18
Stock-based compensation expense	787				787
Other comprehensive income	453						453
Net loss	(7,837)							(7,837)
Balance at Mar. 31, 2020	36,346		$ 1		84,820		474	(48,949)
Balance, Shares at Mar. 31, 2020			17,683,965
Balance at Dec. 31, 2020	69,854		$ 2		141,074		(297)	(70,925)
Balance, Shares at Dec. 31, 2020			24,753,102
Issuance of common stock under registered direct offering, net of offering costs	29,909				29,909
Issuance of common stock under registered direct offering, net of offering costs, Shares			4,285,710
Exercise of stock options	4				4
Exercise of stock options, Shares			1,458
Vesting of restricted stock liability	18				18
Stock-based compensation expense	1,044				1,044
Other comprehensive income	42						42
Net loss	(8,991)							(8,991)
Balance at Mar. 31, 2021	$ 91,880		$ 2		$ 172,049		$ (255)	$ (79,916)
Balance, Shares at Mar. 31, 2021			29,040,270

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Operating activities:
Net loss	$ (8,991,000)	$ (7,837,000)
Adjustments to reconcile net loss to cash used in operating activities:
Depreciation and amortization	17,000	8,000
Stock-based compensation	1,044,000	787,000
Net unrealized loss on foreign currency transactions	50,000	336,000
Non-cash consulting expense		81,000
Amortization of term loan discount and issuance costs	64,000	65,000
Realized gain on investments	0	(13,000)
Amortization/accretion of investments, net	100,000	(7,000)
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	481,000	299,000
Accounts payable	(489,000)	(39,000)
Accrued expenses	(220,000)	(50,000)
Net cash used in operating activities	(7,944,000)	(6,370,000)
Investing activities:
Purchases of property and equipment		(15,000)
Purchases of short-term investments	(7,605,000)	(2,225,000)
Maturities of short-term investments	12,465,000	15,245,000
Net cash provided by investing activities	4,860,000	13,005,000
Financing activities:
Proceeds from registered direct offering, net of offering costs	29,960,000
Proceeds from exercise of stock options	4,000
Net cash provided by financing activities	29,964,000	775,000
Effect of exchange rate changes on cash and cash equivalents	(1,000)	(15,000)
Net increase in cash and cash equivalents	26,879,000	7,395,000
Cash and cash equivalents at beginning of period	23,982,000	13,219,000
Cash and cash equivalents at end of period	50,861,000	20,614,000
Supplemental disclosures of non-cash activities:
Registered direct offering issuance costs in accounts payable	$ 50,000
ATM Facility
Financing activities:
Proceeds from issuance of common stock, net of issuance costs		775,000
Lincoln Park Capital Fund, LLC
Supplemental disclosures of non-cash activities:
Issuance of commitment shares to Lincoln Park pursuant to agreement		$ 171,000

Organization and Accounting Pro

Organization and Accounting Pronouncements	3 Months Ended
	Mar. 31, 2021
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Organization and Accounting Pronouncements	1. Organization and Accounting Pronouncements Description of Business Equillium, Inc. (the Company) was incorporated in the state of Delaware on March 16, 2017 . The Company is a clinical-stage biotechnology company leveraging deep understanding of immunology to develop novel products to treat severe autoimmune and inflammatory disorders with high unmet medical need. From inception through March 31, 2021, the Company has devoted substantially all of its efforts to organizing and staffing the Company, business planning, raising capital, in-licensing rights to itolizumab (EQ001), conducting preclinical research, filing three initial Investigational New Drug applications (INDs), conducting clinical development of the Company’s initial product candidate, itolizumab (EQ001), conducting business development activities, and the general and administrative activities associated with operating as a public company. In addition, the Company has a limited operating history, has not generated revenues from its principal operations, and the sales and income potential of its business is unproven. Liquidity and Business Risks As of March 31, 2021, the Company had $ 104.1 million in cash, cash equivalents and short-term investments. The Company has incurred significant operating losses and negative cash flows from operations. The Company expects to use its cash, cash equivalents, and short-term investments to fund research and development of itolizumab (EQ001) and for working capital and other general corporate purposes. The Company does not expect to generate any revenues from product sales unless and until the Company successfully completes development and obtains regulatory approval of itolizumab (EQ001) or any future product candidate, which is unlikely to happen within the next 12 months, if ever. Accordingly, until such time as the Company can generate significant revenue from sales of its product candidates, if ever, the Company expects to finance its cash needs through a combination of equity offerings, debt financings, and collaboration and license agreements. However, the Company may not be able to secure additional financing or enter into such other arrangements in a timely manner or on favorable terms, if at all. As a result of the COVID-19 pandemic and actions taken to slow its spread, the global credit and financial markets have experienced extreme volatility, including diminished liquidity and credit availability, declines in consumer confidence, declines in economic growth, increases in unemployment rates and uncertainty about economic stability. There can be no assurance that further deterioration in credit and financial markets and confidence in economic conditions will not occur. If equity and credit markets deteriorate, it may make any necessary debt or equity financing more difficult to obtain, more costly and/or more dilutive. The Company’s failure to raise capital or enter into such other arrangements when needed would have a negative impact on the Company’s financial condition and could force the Company to delay, reduce or terminate its research and development programs or other operations, or grant rights to develop and market product candidates that the Company would otherwise prefer to develop and market itself. Management believes that the Company’s cash, cash equivalents and short-term investments as of March 31, 2021 will be sufficient to fund operations for at least the next 12 months from the date this Quarterly Report on Form 10-Q is filed with the Securities and Exchange Commission (SEC). The COVID-19 outbreak in the United States and the rest of the world has caused disruptions to the Company’s business, which has delayed results of the Company’s clinical trials and adversely impacted the Company’s business. The Company cannot predict how legal and regulatory responses to concerns about COVID-19 or other major public health issues will impact the Company’s business, nor can it predict potential adverse impacts related to the availability of capital to fund the Company’s operations. Additionally, the Company’s workforce and outside consultants may also be affected, which could result in an adverse impact on the Company’s ability to conduct business. Any of these factors, alone or in combination with others, could harm the Company’s business, results of operations, financial condition or liquidity. However, the magnitude, timing, and duration of any such potential financial impacts cannot be reasonably estimated at this time. Basis of Presentation The accompanying condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) and the rules and regulations of the SEC related to a quarterly report on Form 10-Q. Any reference in these notes to applicable guidance is meant to refer to GAAP as found in the Accounting Standards Codification (ASC) and Accounting Standards Updates (ASU) promulgated by the Financial Accounting Standards Board (FASB). Certain information and note disclosures normally included in annual financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to those rules and regulations. The condensed consolidated financial statements reflect all adjustments which, in the opinion of management, are necessary for a fair statement of the results for the periods presented. All such adjustments are of a normal and recurring nature. The operating results presented in these condensed consolidated financial statements are not necessarily indicative of the results that may be expected for any future periods. These condensed consolidated financial statements should be read in conjunction with the audited financial statements and the notes thereto for the year ended December 31, 2020 included in the Company’s Annual Report on Form 10-K filed with the SEC on March 24, 2021. Principles of Consolidation In January 2019, the Company created a new wholly-owned subsidiary in Australia with the Company serving as the sole shareholder through the subscription of shares. The accompanying condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiary. All intercompany transactions and balances have been eliminated in consolidation. Foreign Currency Translation The Company’s wholly-owned subsidiary in Australia uses their local currency as its functional currency. Assets and liabilities are translated into U.S. dollars at quarter-end exchange rates and revenues and expenses are translated at average exchange rates during the quarter and year-to-date periods. Foreign currency translation adjustments for the reported periods are included in accumulated other comprehensive income in the Company’s condensed consolidated statements of comprehensive loss, and the cumulative effect is included in the stockholders’ equity section of the Company’s condensed consolidated balance sheets. Realized and unrealized gains and losses denominated in foreign currencies are recorded in operating expenses in the Company’s condensed consolidated statements of operations. For the three months ended March 31, 2021 and 2020, net realized and unrealized gains totaled $ 0.1 million and $ 0.3 million, respectively. Recent Accounting Pronouncements In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) , which amends the FASB ASC 840 and creates Topic 842, Leases. The new topic supersedes Topic 840, Leases, and increases transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheet and requires disclosures of key information about leasing arrangements. For companies that are not emerging growth companies (EGCs), ASU 2016-02 is effective for fiscal years beginning after December 15, 2018. For EGCs, the ASU was to be effective for fiscal years beginning after December 15, 2019. However, in November 2019, the FASB issued ASU 2019-10, Financial Instruments—Credit Losses (Topic 326) , Derivatives and Hedging (Topic 815) and Leases (Topic 842 ), Effective Dates (ASU 2019-10), which included a one-year deferral of the effective date of ASU 2016-02 for certain entities. As a result, the ASU is now effective for EGCs for fiscal years beginning after December 15, 2020, and interim periods within fiscal years beginning after December 15, 2021. The Company expects to adopt the new standard in the fourth quarter of 2021 using the modified retrospective method, under which the Company will apply Topic 842 to existing and new leases as of January 1, 2021, but prior periods will not be restated and will continue to be reported under Topic 840 guidance in effect during those periods. The Company anticipates that the adoption will not have a material impact on its consolidated statements of operations and consolidated comprehensive loss or its consolidated statements of cash flows but expects to recognize right-of-use assets and liabilities for lease obligations associated with its operating leases. In June 2016, the FASB issued ASU No. 2016-13, Measurement of Credit Losses on Financial Instruments , which will require a reporting entity to use a new forward-looking impairment model for most financial assets that generally will result in the earlier recognition of allowances for losses. The ASU, along with related amendments, revised the measurement of credit losses for financial assets measured at amortized cost from an incurred loss to an expected loss methodology. The ASU affected receivables, debt securities, net investment in leases, and most other financial assets that represent a right to receive cash. The standard and other related subsequently issued ASUs will be effective for the Company for annual periods beginning after December 15, 2022, with early adoption permitted beginning in 2019. The Company is currently evaluating the impact that the adoption of the standard and other related subsequently issued ASUs will have on its consolidated financial statements and accompanying footnotes. Adopted Accounting Pronouncements In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes . The amendments in this ASU simplify the accounting for income taxes by removing certain exceptions to the general principles in Topic 740. The amendments also improve consistent application of and simplify GAAP for other areas of Topic 740 by clarifying and amending existing guidance. The amendments in this ASU are effective for the Company on January 1, 2021. The adoption of this standard did not have a material impact on the Company's condensed consolidated financial statements.

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Use of Estimates The preparation of the Company’s condensed consolidated financial statements requires the Company to make estimates and assumptions that impact the reported amounts of assets, liabilities and expenses and the disclosure of contingent assets and liabilities in the condensed consolidated financial statements and accompanying notes. Significant estimates in the Company’s condensed consolidated financial statements relate to clinical trial accruals and the valuation of equity awards. Management evaluates its estimates on an ongoing basis. Although estimates are based on the Company’s historical experience, knowledge of current events, and actions it may undertake in the future, actual results may ultimately materially differ from these estimates and assumptions. Accrued Research and Development Expense The Company is required to estimate its expenses resulting from its obligations under contracts with vendors, consultants and contract research organizations, in connection with conducting research and development activities. The financial terms of these contracts are subject to negotiations, which vary from contract to contract and may result in payment flows that do not match the periods over which materials or services are provided under such contracts. The Company reflects research and development expenses in its condensed consolidated financial statements by matching those expenses with the period in which services and efforts are expended. The Company accounts for these expenses according to the progress of the preclinical or clinical study as measured by the timing of various aspects of the study or related activities. The Company determines accrual estimates through review of the underlying contracts along with preparation of financial models taking into account discussions with research and development personnel and other key personnel as well as considering input from representatives of our contract service providers as to the progress of studies, or other services being conducted. During the course of a study, the Company adjusts its rate of expense recognition if actual results differ from its estimates. The Company classifies its estimates for accrued research and development expenses as accrued expenses on the accompanying condensed consolidated balance sheet. Australian Research and Development Tax Incentive The Company is eligible under the Australian Research and Development Tax Incentive Program, or the Tax Incentive, to obtain a cash refund from the Australian Taxation Office for eligible research and development expenditures. However, the Company must have revenue of less than AUD $ 20.0 million during the reimbursable period and cannot be controlled by income tax exempt entities. The Tax Incentive is recognized as a reduction to research and development expense when there is a reasonable assurance that the Tax Incentive will be received, the relevant expenditure has been incurred, and the amount can be reliably measured. The Company classifies its estimate for the Tax Incentive as prepaid expenses and other current assets on the accompanying condensed consolidated balance sheet. Stock-Based Compensation The Company measures employee and non-employee stock-based awards, including stock options and stock purchase rights, at grant-date fair value and records compensation expense on a straight-line basis over the vesting period of the award. The Company uses the Black-Scholes option pricing model to value its stock option awards. Estimating the fair value of stock option awards requires management to apply judgment and make estimates of certain assumptions, including the volatility of the Company’s common stock, the expected term of the Company’s stock options, the expected dividend yield and the fair value of the Company’s common stock on the measurement date. As a result, if factors change and management uses different assumptions, stock-based compensation expense could be materially different for future awards. Net Loss per Share Basic net loss per share is calculated by dividing the net loss by the weighted-average number of common shares outstanding for the period. Diluted net loss per share is computed by dividing the net loss by the weighted average number of common shares and common share equivalents outstanding for the period. Common stock equivalents are only included when their effect is dilutive. The Company’s potentially dilutive securities include outstanding options under the Company’s equity incentive plan and outstanding warrants to purchase common stock, each of which have been excluded from the computation of diluted net loss per share as they would be anti-dilutive to the net loss per share. For all periods presented, there is no difference in the number of shares used to calculate basic and diluted shares outstanding due to the Company’s net loss position. Potentially dilutive securities not included in the calculation of diluted net loss per share attributable to common stockholders because to do so would be anti-dilutive are as follows (in common stock equivalent shares): Three Months Ended 2021 2020 Common stock options 3,946,817 2,014,093 Common stock warrants 1,366,141 80,428 Total 5,312,958 2,094,521

Fair Value of Financial Instrum

Fair Value of Financial Instruments	3 Months Ended
	Mar. 31, 2021
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	3. Fair Value of Financial Instruments The following tables summarize the Company’s assets that require fair value measurements on a recurring basis and their respective input levels based on the fair value hierarchy (in thousands): Fair Value Measurements Using Quoted Prices in Significant Significant Active Markets Other Unobservable March 31, for Identical Observable Inputs 2021 Assets (Level 1) Inputs (Level 2) (Level 3) Short-term investments: U.S. treasury securities $ 52,727 $ 52,727 $ - $ - Certificates of deposit 491 491 - - Total $ 53,218 $ 53,218 $ - $ - Fair Value Measurements Using Quoted Prices in Significant Significant Active Markets Other Unobservable December 31, for Identical Observable Inputs 2020 Assets (Level 1) Inputs (Level 2) (Level 3) Short-term investments: U.S. treasury securities $ 56,220 $ 56,220 $ - $ - Certificates of deposit 1,961 1,961 - - Total $ 58,181 $ 58,181 $ - $ - U.S. treasury securities and certificates of deposit are valued using Level 1 inputs. Level 1 securities are valued at unadjusted quoted prices in active markets that are observable at the measurement date for identical, unrestricted assets or liabilities. Fair values determined by Level 2 inputs, which utilize data points that are observable such as quoted prices, interest rates and yield curves, require the exercise of judgment and use of estimates, that if changed, could significantly affect the Company’s financial position and results of operations. Investments in agency securities are valued using Level 2 inputs. Level 2 securities are initially valued at the transaction price and subsequently valued and reported utilizing inputs other than quoted prices that are observable either directly or indirectly, such as quotes from third-party pricing vendors. The carrying amounts of the Company’s financial instruments, including cash, prepaid and other current assets, accounts payable, and accrued liabilities, approximate fair value due to their short maturities. The carrying amount of the Company’s notes payable of $ 10.0 million at March 31, 2021 approximated their fair value as the terms of the notes are consistent with the market terms of transactions with similar profiles (Level 2 inputs). None of the Company’s non-financial assets or liabilities are recorded at fair value on a non-recurring basis. At March 31, 2021 and December 31, 2020, the Company had investments in money market funds of $ 42.4 million and $ 17.4 million, respectively, that were measured at fair value using the net asset value per share (or its equivalent) that have not been classified in the fair value hierarchy. The funds invest primarily in U.S. government securities. The Company did not hold any Level 1, 2 or 3 financial liabilities that are recorded at fair value on a recurring basis as of March 31, 2021 or December 31, 2020.

Certain Financial Statement Cap

Certain Financial Statement Caption Information	3 Months Ended
	Mar. 31, 2021
Certain Financial Statement Caption Information [Abstract]
Certain Financial Statement Caption Information	4. Certain Financial Statement Caption Information Short-Term Investments The following table summarizes the Company’s short-term investments (in thousands): Maturity Amortized Unrealized Unrealized Estimated (in years) Cost Gains Losses Fair Value March 31, 2021 U.S. treasury securities 1 or less $ 50,165 $ 5 $ - $ 50,170 U.S. treasury securities > 1 and < 5 2,558 - ( 1 ) 2,557 Certificates of deposit 1 or less 490 1 - 491 Total $ 53,213 $ 6 $ ( 1 ) $ 53,218 December 31, 2020 U.S. treasury securities 1 or less $ 56,218 $ 6 $ ( 4 ) $ 56,220 Certificates of deposit 1 or less 1,955 6 - 1,961 Total $ 58,173 $ 12 $ ( 4 ) $ 58,181 All of the Company’s available-for-sale securities are available to the Company for use in its current operations. As a result, the Company categorizes all of these securities as current assets even though the stated maturity of some individual securities may be one year or more beyond the balance sheet date. All of the Company’s securities have a maturity within two years of the balance sheet date. There were no impairments considered other-than-temporary during the periods presented, as it is management’s intention and ability to hold the securities until a recovery of the cost basis or recovery of fair value. For the three months ended March 31, 2021 and 2020, there were net gross realized gains on short-term investments totaling $ 0 and $ 13,000 , respectively. Unrealized gains and losses are included in accumulated other comprehensive loss. Accrued Expenses Accrued expenses consisted of the following (in thousands): March 31, December 31, 2021 2020 Accrued payroll and other employee benefits $ 1,104 $ 1,870 Clinical studies 1,081 493 Other accruals 235 307 Preclinical studies 102 72 Accrued interest 71 71 Total accrued expenses $ 2,593 $ 2,813

Notes Payable

Notes Payable	3 Months Ended
	Mar. 31, 2021
Debt Disclosure [Abstract]
Notes Payable	5. Notes Payable On September 30, 2019 (the Effective Date), the Company entered into a Loan and Security Agreement (the Loan Agreement) with two lenders (the Lenders) whereby the Company can borrow up to $ 20.0 million in a series of term loans. Upon entering into the Loan Agreement, the Company borrowed $ 10.0 million from the Lenders (Term A Loan). Under the terms of the Loan Agreement, the Company may, at its sole discretion, borrow from the Lenders (i) up to an additional $ 5.0 million (Term B Loan) upon the Company’s achievement of positive topline data in either the Company’s (a) Phase 1b aGVHD trial of itolizumab (EQ001) or (b) Phase 1b asthma trial of itolizumab (EQ001), supporting a formal decision to advance into Phase 2 development, and as confirmed by the Company’s Board of Directors (the Term B Milestone) and (ii) up to an additional $ 5.0 million (Term C Loan and together with Term A Loan and Term B Loan, the Term Loans) upon the Company’s achievement of positive topline data in both the Company’s Phase 1b aGVHD trial of itolizumab (EQ001) and the Company’s Phase 1b asthma trial of itolizumab (EQ001), supporting a formal decision to advance into Phase 2 development, and as confirmed by the Company’s Board of Directors (the Term C Milestone). The Company may draw the Term B Loan during the period commencing on the date of the occurrence of the Term B Milestone and ending on the earliest of (i) December 31, 2020, (ii) 60 days after achieving the Term B Milestone, and (iii) the occurrence of an event of default. The Company may draw the Term C Loan during the period commencing on the date of the occurrence of the Term C Milestone and ending on the earliest of (i) December 31, 2020, (ii) 60 days after achieving the Term C Milestone, and (iii) the occurrence of an event of default. As of December 31, 2020, the Company did not achieve the Term B or Term C Milestone and is not eligible to receive the additional funding up to $ 10.0 million under the Loan Agreement. All of the Term Loans mature on June 1, 2024 (the Maturity Date) and will be interest-only payments through June 30, 2021, followed by 36 equal monthly payments of principal and interest; provided that if the Company draws the Term B Loan, the Term Loans will be interest-only payments through December 31, 2021, followed by 30 equal monthly payments of principal and interest. The Term Loans bear interest at a floating per annum rate equal to the greater of (i) 8.25 % and (ii) the sum of (a) the prime rate reported in The Wall Street Journal on the last business day of the month that immediately precedes the month in which the interest will accrue, plus (b) 3.00 %. The Company will be required to make a final payment of 4.50 % of the original principal amount of the Term Loans drawn payable on the earlier of (i) the Maturity Date, (ii) the acceleration of any Term Loans, or (iii) the prepayment of the Term Loans (the Final Payment). The Company may prepay all, but not less than all, of the Term Loans upon 30 days ’ advance written notice to the Lenders, provided that the Company will be obligated to pay a prepayment fee equal to (i) 3.00 % of the principal amount of the applicable Term Loan prepaid on or before the first anniversary of the applicable funding date, (ii) 2.00 % of the principal amount of the applicable Term Loan prepaid between the first and second anniversary of the applicable funding date, and (iii) 1.00 % of the principal amount of the applicable Term Loan prepaid thereafter, and prior to the Maturity Date (each, a Prepayment Fee). In connection with entering into the Loan Agreement, the Company issued to the Lenders warrants exercisable for 80,428 shares of the Company’s common stock (the Warrants). The Warrants are exercisable in whole or in part, immediately, and have a per share exercise price of $ 3.73 , which was the closing price of the Company’s common stock reported on the Nasdaq Global Market on the day prior to the Effective Date. The Warrants will terminate on the earlier of September 30, 2029 or the closing of certain merger or consolidation transactions. If the Company borrows under Term B Loan and/or Term C Loan, upon the funding of Term B Loan and/or Term C Loan, as applicable, the Company will issue to the Lenders additional warrants to purchase shares of the Company’s common stock equal to 3.00 % of each Term Loan amount divided by the lower of (i) the ten day average closing price of the Company’s common stock reported on the Nasdaq Global Market prior to funding or (ii) the closing price of the Company’s common stock reported on the Nasdaq Global Market on the day prior to funding. Such lower amount of (i) and (ii) above shall also be the exercise price per share for such warrants. The terms of such warrants would be substantially the same as those contained in the Warrants. The Company recorded the Warrants as a debt discount, which is classified as a contra-liability against long-term notes payable on the condensed consolidated balance sheet, and is amortizing the balance over the life of the underlying debt. The offset to the contra-liability is recorded in additional paid-in capital in the Company’s condensed consolidated balance sheet as the Warrants were determined to be an equity instrument. The Company determined the fair value of the Warrants at the date of issuance was $ 0.3 million using the Black-Scholes option pricing model based on significant unobservable inputs (Level 3) with an expected term of 10 years, volatility of 92.78 %, risk free rate of 1.68 % and expected dividend of 0 %. The costs incurred to issue the Term Loans of $ 0.1 million were deferred and are included in the discount to the carrying value of the Term Loans in the accompanying condensed consolidated balance sheet. The deferred costs and the Final Payment fee are amortized to interest expense over the expected term of the Term Loans using the effective interest method with an effective interest rate of 10.97 %. The aggregate carrying amounts of the Term Loans are comprised of the following (in thousands): March 31, December 31, 2021 2020 Principal $ 10,000 $ 10,000 Add: accreted liability for Final Payment fee 211 176 Less: unamortized discount ( 205 ) ( 235 ) Total $ 10,006 $ 9,941 Upon the occurrence of certain events, including but not limited to the Company’s failure to satisfy its payment obligations under the Loan Agreement, the breach of certain of its other covenants under the Loan Agreement, or the occurrence of a material adverse change, cross defaults to other indebtedness or material agreements, judgment defaults and defaults related to failure to maintain governmental approvals failure of which to maintain could result in a material adverse effect, the Lenders will have the right, among other remedies, to declare all principal and interest immediately due and payable, to exercise secured party remedies, to receive the Final Payment and, if the payment of principal and interest is due prior to the Maturity Date, to receive the applicable Prepayment Fee. At March 31, 2021, the Company was in compliance with the covenants contained in the Loan Agreement. On December 18, 2020, the Company entered into the First Amendment to the Loan Agreement (the First Amendment) with the Lenders whereby if the Company achieves the Term B Milestone on or prior to June 30, 2021, the interest-only payments will be automatically extended through December 31, 2021. The Company has not yet achieved the Term B Milestone as of March 31, 2021 and through the date of the filing of this Quarterly Report on Form 10-Q. On April 23, 2021, the Company entered into the Second Amendment to the Loan Agreement (the Second Amendment) which added two new milestones: (i) the Company achieving positive data in the Company's Phase 1b aGVHD trial of itolizumab (EQ001) supporting a formal decision to advance into Phase 2 or Phase 3 development, and as confirmed by the Company's Board of Directors in written board minutes (the Interest-Only Extension Milestone) and (ii) the Company initiating a pivotal Phase 3 aGVHD trial (the Interest-Only Extension II Milestone). If the Company achieves the Interest-Only Milestone on or prior to June 30, 2021, then interest-only payments will be automatically extended through June 30, 2022. If the Company achieves the Interest-Only Extension II Milestone on or prior to June 30, 2022, then interest-only payments will be automatically extended through September 30, 2022. The Company has not yet achieved either the Interest-Only Extension Milestone or the Interest-Only Extension II Milestone since the execution date of the Second Amendment and through the date of the filing of this Quarterly Report on Form 10-Q. The Second Amendment also amended the final payment percentage from 4.5 % to 5.0 %. Future maturities of the Term Loans, including the Final Payment fee, as of March 31, 2021 are as follows (in thousands): March 31, 2021 Remainder of 2021 $ 1,667 Year ending December 31, 2022 3,333 Year ending December 31, 2023 3,333 Year ending December 31, 2024 2,117 10,450 Unaccreted balance for Final Payment fee on Term Loans ( 239 ) Unamortized discounts ( 205 ) 10,006 Less current portion ( 2,500 ) Noncurrent portion $ 7,506

Collaboration and License Agree

Collaboration and License Agreement	3 Months Ended
	Mar. 31, 2021
Collaboration And License Agreement [Abstract]
Collaboration and License Agreement	6. Collaboration and License Agreement In May 2017, the Company entered into a collaboration and license agreement (which was amended in September 2018, April 2019, December 2019, and April 2021), clinical supply agreement, investor rights agreement, and common stock purchase agreement (collectively License Agreements) with Biocon SA (together with Biocon Limited, Biocon). Pursuant to the License Agreements, Biocon granted the Company an exclusive license to develop, make, have made, use, sell, have sold, offer for sale, import and otherwise exploit itolizumab and any pharmaceutical composition or preparation containing or comprising itolizumab that uses Biocon technology or Biocon know-how (collectively a Biocon Product) in the United States, Canada, Australia and New Zealand (collectively Company Territory). However, unless the Company achieves certain regulatory and development milestones within a specific time period, the licensed rights, other than development rights, are limited to the fields of orphan indications and the treatment of conditions related to asthma and lupus. The Company also has the right to sublicense through multiple tiers to third parties, provided such sublicenses comply with the terms of the License Agreements and the Company provides Biocon a copy of each sublicense agreement within 30 days of execution. If the Company grants a third party a sublicense of its rights to develop and commercialize Biocon Products in Australia or New Zealand, the Company will be required to pay Biocon a high double-digit percentage of any upfront payment the Company receives from such sublicensee for such sublicense, as well as a high double-digit percentage of any additional payments the Company receives from such sublicensee for such sublicense, including but not limited to royalty payments on net sales of Biocon Products by such sublicensee. Under the License Agreements, the Company granted back to Biocon a license to use its technology and know-how related to itolizumab and Biocon Products in certain countries outside of the Company’s Territory. Pursuant to the License Agreements, Biocon agreed to be the Company’s exclusive supplier of itolizumab clinical drug product. Biocon will provide clinical drug product at no cost for up to three concurrent orphan indications until the Company’s first U.S. regulatory approval and all other clinical drug product at Biocon’s cost. In consideration of the rights granted to the Company by Biocon, the Company issued Biocon a total of 2,316,134 shares of common stock. In addition, the Company is obligated to pay Biocon up to an aggregate of $ 30 million in regulatory milestone payments upon the achievement of certain regulatory approvals and up to an aggregate of $ 565 million in sales milestone payments upon the achievement of first commercial sale of product and specified levels of product sales. The Company is also required to pay royalties on tiers of aggregate annual net sales of Biocon Products by the Company, the Company’s affiliates and the Company’s sublicensees in the United States and Canada at percentages from the mid-single digits to sub-teen double-digits and on tiers of aggregate annual net sales of Biocon Products by the Company and the Company’s affiliates (but not the Company’s sublicensees) in Australia and New Zealand, in each case, subject to adjustments in certain circumstances. Biocon is also required to pay the Company royalties at comparable percentages for sales of itolizumab (EQ001) outside of the Company Territory if the approvals in such geographies included or referenced the Company’s data including data from certain of the Company’s clinical trials, subject to adjustments in certain circumstances. Under the License Agreements, net sales are calculated on a country-by-country basis and are subject to adjustments, including whether the Biocon Product is sold in the form of a combination product. As of March 31, 2021, the Company has not made or received payments in connection with the milestones or royalties within the agreement.

Stockholders' Equity

Stockholders' Equity	3 Months Ended
	Mar. 31, 2021
Equity [Abstract]
Stockholders’ Equity	7. Stockholders’ Equity As of March 31, 2021 , the Company’s authorized capital stock consisted of 200,000,000 shares of common stock, par value $ 0.0001 per share, and 10,000,000 shares of preferred stock, par value $ 0.0001 per share. The Company had 29,040,270 and 24,753,102 shares of common stock outstanding as of March 31, 2021 and December 31, 2020, respectively. Registered Direct Offering and related warrants On February 3, 2021, the Company entered into a securities purchase agreement (the Securities Purchase Agreement) with two institutional investors (the Purchasers), relating to the issuance and sale (the Offering) of an aggregate of 4,285,710 shares of common stock and warrants to purchase 1,285,713 shares of common stock (the Warrants) for aggregate gross proceeds to the Company from this Offering of approximately $ 30.0 million, excluding any proceeds the Company may receive upon exercise of the Warrants. No underwriter or placement agent participated in the Offering. The proceeds, net of related issuance costs, were $ 29.9 million. The Warrants are exercisable immediately upon issuance at an initial exercise price of $ 14.00 per share and are exercisable on a cashless basis. The Warrants expire on the earlier of (i) the fifth anniversary of issuance or (ii) the 15 th calendar date following the date on which the Company closes upon an equity financing that results in not less than $ 25 million of gross proceeds to the Company at a price per share of common stock equal to or greater than $ 25.00 , at which time, all remaining Warrants will automatically be exercised on a cashless basis. The exercise price and the number of shares of common stock purchasable upon the exercise of the Warrants are subject to adjustment upon the occurrence of specific events, including stock dividends, stock splits, reclassifications and combinations of the Company’s common stock. All of the warrants are recorded within equity in accordance with authoritative accounting guidance. Pursuant to the terms of the Securities Purchase Agreement, the Company agreed to appoint Dr. Yu (Katherine) Xu, Ph. D. to the Board as a nominee of the Purchasers. Follow-On Public Offering In August 2020, the Company completed an underwritten public offering of 5,461,169 shares of common stock at $ 7.00 per share, which included 461,169 shares sold pursuant to the exercise of the underwriters’ option to purchase additional shares. The Company received gross proceeds from this offering totaling $ 38.2 million. The proceeds, net of underwriting discounts and related issuance costs, were $ 35.7 million. At-the-Market Offering Program In November 2019, the Company entered into an Open Market Sales Agreement SM with Jefferies LLC (Jefferies) under which the Company could offer and sell shares of its common stock from time to time, through an “at-the-market”, or ATM, equity offering program under which Jefferies acted as sales agent (2019 ATM Facility). The Company set certain parameters for the sale of shares, which included but were not limited to the number of shares to be issued, the time period during which sales are requested to be made, and any minimum price below which sales may not be made. Jefferies was entitled to compensation for its services at a commission rate of 3.0 % of the gross sales price per share of common stock sold plus reimbursement of certain expenses. The maximum aggregate offering price of common stock that could be sold under the 2019 ATM Facility was $ 8.45 million. The 2019 ATM Facility was fully utilized as of early July 2020 and, therefore, there was no activity during the three months ended March 31, 2021. During the three months ended March 31, 2020, the Company sold an aggregate of 174,649 shares of its common stock under the 2019 ATM Facility resulting in net proceeds of $ 0.8 million. On July 14, 2020, the Company entered into a new ATM equity offering program (2020 ATM Facility) with Jefferies under which the Company may offer and sell shares of the Company’s common stock having an aggregate price of up to $ 150 million, from time to time, through Jefferies acting as our sales agent. During the three months ended March 31, 2021 and 2020, there was no activity under the 2020 ATM Facility. As of March 31, 2021, the Company sold an aggregate of 788,685 shares of common stock under the 2020 ATM Facility and received gross proceeds of $ 10.4 million. The Company paid commissions on the gross proceeds, plus reimbursement of expenses to Jefferies and other issuance costs in the aggregate amount of approximately $ 0.4 million, resulting in net proceeds of $ 10.0 million. Since March 31, 2021 and through the date of the filing of this Quarterly Report on Form 10-Q, there have been no additional sales of the Company’s stock under the 2020 ATM Facility. Purchase Agreement On March 27, 2020, the Company entered into a purchase agreement (Purchase Agreement), with Lincoln Park Capital Fund, LLC (Lincoln Park), which provides that, upon the terms and subject to the conditions and limitations set forth therein, the Company may sell to Lincoln Park up to $ 15.0 million of shares of its common stock from time to time over the 36-month term of the Purchase Agreement. Upon execution of the Purchase Agreement, the Company issued 65,374 shares of its common stock to Lincoln Park as commitment shares in accordance with the closing conditions contained within the Purchase Agreement. The commitment shares were valued using the closing price of the Company’s common stock on the effective date of the Purchase Agreement resulting in a fair market value of approximately $ 0.2 million. The fair market value of the commitment shares as well as other issuance costs associated with the Purchase Agreement totaled $ 0.4 million. These issuance costs are classified as prepaid expenses and other current assets in the accompanying condensed consolidated balance sheet. As shares of common stock are sold to Lincoln Park in accordance with the Purchase Agreement, the issuance costs, including the fair value of the commitment shares, will be reclassified to additional paid-in capital on the Company’s condensed consolidated balance sheet. There have been no sales of the Company’s stock under this Purchase Agreement as of March 31, 2021 and through the date of the filing of this Quarterly Report on Form 10-Q. Stock Options The following table summarizes the stock option activity during the three months ended March 31, 2021: Shares Weighted- Weighted Aggregate Options outstanding at December 31, 2020 2,463,317 $ 3.71 Granted 1,493,500 $ 5.14 Exercised ( 1,458 ) $ 2.45 Forfeitures and cancellations ( 8,542 ) $ 3.96 Options outstanding at March 31, 2021 3,946,817 $ 4.25 8.51 $ 11,473 Options exercisable at March 31, 2021 1,210,431 $ 3.48 6.83 $ 4,453 (a) Aggregate intrinsic value in this table was calculated as the positive difference, if any, between the closing price per share of the Company’s common stock on March 31, 2021 of $ 7.15 and the price of the underlying options. At March 31, 2021, unamortized stock compensation for stock options was $ 11.0 million, with a weighted-average recognition period of 2.9 years. Stock-Based Compensation Expense The non-cash stock-based compensation expense for all stock awards, net of forfeitures recognized as they occur, that was recognized in the condensed consolidated statements of operations is as follows (in thousands): Three Months Ended 2021 2020 Research and development $ 474 $ 414 General and administrative 570 373 Total $ 1,044 $ 787 Common Stock Reserved for Future Issuance Common stock reserved for future issuance at March 31, 2021 is as follows: March 31, December 31, 2021 2020 Stock options issued and outstanding 3,946,817 2,463,317 Warrants for common stock 1,366,141 80,428 Awards available under the 2018 Equity Incentive Plan 792,228 1,039,531 Employee stock purchase plan 860,060 612,529 Total 6,965,246 4,195,805

Subsequent Events

Subsequent Events	3 Months Ended
	Mar. 31, 2021
Subsequent Events [Abstract]
Subsequent Events	8. Subsequent Events As described in further detail in Note 5, the Company amended its Loan Agreement with its Lenders on April 23, 2021 .

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Recently Issued Accounting Pronouncements	Recent Accounting Pronouncements In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) , which amends the FASB ASC 840 and creates Topic 842, Leases. The new topic supersedes Topic 840, Leases, and increases transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheet and requires disclosures of key information about leasing arrangements. For companies that are not emerging growth companies (EGCs), ASU 2016-02 is effective for fiscal years beginning after December 15, 2018. For EGCs, the ASU was to be effective for fiscal years beginning after December 15, 2019. However, in November 2019, the FASB issued ASU 2019-10, Financial Instruments—Credit Losses (Topic 326) , Derivatives and Hedging (Topic 815) and Leases (Topic 842 ), Effective Dates (ASU 2019-10), which included a one-year deferral of the effective date of ASU 2016-02 for certain entities. As a result, the ASU is now effective for EGCs for fiscal years beginning after December 15, 2020, and interim periods within fiscal years beginning after December 15, 2021. The Company expects to adopt the new standard in the fourth quarter of 2021 using the modified retrospective method, under which the Company will apply Topic 842 to existing and new leases as of January 1, 2021, but prior periods will not be restated and will continue to be reported under Topic 840 guidance in effect during those periods. The Company anticipates that the adoption will not have a material impact on its consolidated statements of operations and consolidated comprehensive loss or its consolidated statements of cash flows but expects to recognize right-of-use assets and liabilities for lease obligations associated with its operating leases. In June 2016, the FASB issued ASU No. 2016-13, Measurement of Credit Losses on Financial Instruments , which will require a reporting entity to use a new forward-looking impairment model for most financial assets that generally will result in the earlier recognition of allowances for losses. The ASU, along with related amendments, revised the measurement of credit losses for financial assets measured at amortized cost from an incurred loss to an expected loss methodology. The ASU affected receivables, debt securities, net investment in leases, and most other financial assets that represent a right to receive cash. The standard and other related subsequently issued ASUs will be effective for the Company for annual periods beginning after December 15, 2022, with early adoption permitted beginning in 2019. The Company is currently evaluating the impact that the adoption of the standard and other related subsequently issued ASUs will have on its consolidated financial statements and accompanying footnotes. Adopted Accounting Pronouncements In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes . The amendments in this ASU simplify the accounting for income taxes by removing certain exceptions to the general principles in Topic 740. The amendments also improve consistent application of and simplify GAAP for other areas of Topic 740 by clarifying and amending existing guidance. The amendments in this ASU are effective for the Company on January 1, 2021. The adoption of this standard did not have a material impact on the Company's condensed consolidated financial statements.
Use of Estimates	Use of Estimates The preparation of the Company’s condensed consolidated financial statements requires the Company to make estimates and assumptions that impact the reported amounts of assets, liabilities and expenses and the disclosure of contingent assets and liabilities in the condensed consolidated financial statements and accompanying notes. Significant estimates in the Company’s condensed consolidated financial statements relate to clinical trial accruals and the valuation of equity awards. Management evaluates its estimates on an ongoing basis. Although estimates are based on the Company’s historical experience, knowledge of current events, and actions it may undertake in the future, actual results may ultimately materially differ from these estimates and assumptions.
Accrued Research and Development Expense	Accrued Research and Development Expense The Company is required to estimate its expenses resulting from its obligations under contracts with vendors, consultants and contract research organizations, in connection with conducting research and development activities. The financial terms of these contracts are subject to negotiations, which vary from contract to contract and may result in payment flows that do not match the periods over which materials or services are provided under such contracts. The Company reflects research and development expenses in its condensed consolidated financial statements by matching those expenses with the period in which services and efforts are expended. The Company accounts for these expenses according to the progress of the preclinical or clinical study as measured by the timing of various aspects of the study or related activities. The Company determines accrual estimates through review of the underlying contracts along with preparation of financial models taking into account discussions with research and development personnel and other key personnel as well as considering input from representatives of our contract service providers as to the progress of studies, or other services being conducted. During the course of a study, the Company adjusts its rate of expense recognition if actual results differ from its estimates. The Company classifies its estimates for accrued research and development expenses as accrued expenses on the accompanying condensed consolidated balance sheet.
Australian Research and Development Tax Incentive	Australian Research and Development Tax Incentive The Company is eligible under the Australian Research and Development Tax Incentive Program, or the Tax Incentive, to obtain a cash refund from the Australian Taxation Office for eligible research and development expenditures. However, the Company must have revenue of less than AUD $ 20.0 million during the reimbursable period and cannot be controlled by income tax exempt entities. The Tax Incentive is recognized as a reduction to research and development expense when there is a reasonable assurance that the Tax Incentive will be received, the relevant expenditure has been incurred, and the amount can be reliably measured. The Company classifies its estimate for the Tax Incentive as prepaid expenses and other current assets on the accompanying condensed consolidated balance sheet.
Stock-Based Compensation	Stock-Based Compensation The Company measures employee and non-employee stock-based awards, including stock options and stock purchase rights, at grant-date fair value and records compensation expense on a straight-line basis over the vesting period of the award. The Company uses the Black-Scholes option pricing model to value its stock option awards. Estimating the fair value of stock option awards requires management to apply judgment and make estimates of certain assumptions, including the volatility of the Company’s common stock, the expected term of the Company’s stock options, the expected dividend yield and the fair value of the Company’s common stock on the measurement date. As a result, if factors change and management uses different assumptions, stock-based compensation expense could be materially different for future awards.
Net Loss per Share	Net Loss per Share Basic net loss per share is calculated by dividing the net loss by the weighted-average number of common shares outstanding for the period. Diluted net loss per share is computed by dividing the net loss by the weighted average number of common shares and common share equivalents outstanding for the period. Common stock equivalents are only included when their effect is dilutive. The Company’s potentially dilutive securities include outstanding options under the Company’s equity incentive plan and outstanding warrants to purchase common stock, each of which have been excluded from the computation of diluted net loss per share as they would be anti-dilutive to the net loss per share. For all periods presented, there is no difference in the number of shares used to calculate basic and diluted shares outstanding due to the Company’s net loss position. Potentially dilutive securities not included in the calculation of diluted net loss per share attributable to common stockholders because to do so would be anti-dilutive are as follows (in common stock equivalent shares): Three Months Ended 2021 2020 Common stock options 3,946,817 2,014,093 Common stock warrants 1,366,141 80,428 Total 5,312,958 2,094,521

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Summary of Potentially Dilutive Securities Not Included in Calculation of Diluted Net Loss Per Share	Potentially dilutive securities not included in the calculation of diluted net loss per share attributable to common stockholders because to do so would be anti-dilutive are as follows (in common stock equivalent shares): Three Months Ended 2021 2020 Common stock options 3,946,817 2,014,093 Common stock warrants 1,366,141 80,428 Total 5,312,958 2,094,521

Fair Value of Financial Instr_2

Fair Value of Financial Instruments (Tables)	3 Months Ended
	Mar. 31, 2021
Fair Value Disclosures [Abstract]
Summary of Assets that Require Fair Value Measurements on Recurring Basis and Their Respective Input Levels Based on Fair Value Hierarchy	The following tables summarize the Company’s assets that require fair value measurements on a recurring basis and their respective input levels based on the fair value hierarchy (in thousands): Fair Value Measurements Using Quoted Prices in Significant Significant Active Markets Other Unobservable March 31, for Identical Observable Inputs 2021 Assets (Level 1) Inputs (Level 2) (Level 3) Short-term investments: U.S. treasury securities $ 52,727 $ 52,727 $ - $ - Certificates of deposit 491 491 - - Total $ 53,218 $ 53,218 $ - $ - Fair Value Measurements Using Quoted Prices in Significant Significant Active Markets Other Unobservable December 31, for Identical Observable Inputs 2020 Assets (Level 1) Inputs (Level 2) (Level 3) Short-term investments: U.S. treasury securities $ 56,220 $ 56,220 $ - $ - Certificates of deposit 1,961 1,961 - - Total $ 58,181 $ 58,181 $ - $ -

Certain Financial Statement C_2

Certain Financial Statement Caption Information (Tables)	3 Months Ended
	Mar. 31, 2021
Certain Financial Statement Caption Information [Abstract]
Schedule of Company's Short-Term Investments	The following table summarizes the Company’s short-term investments (in thousands): Maturity Amortized Unrealized Unrealized Estimated (in years) Cost Gains Losses Fair Value March 31, 2021 U.S. treasury securities 1 or less $ 50,165 $ 5 $ - $ 50,170 U.S. treasury securities > 1 and < 5 2,558 - ( 1 ) 2,557 Certificates of deposit 1 or less 490 1 - 491 Total $ 53,213 $ 6 $ ( 1 ) $ 53,218 December 31, 2020 U.S. treasury securities 1 or less $ 56,218 $ 6 $ ( 4 ) $ 56,220 Certificates of deposit 1 or less 1,955 6 - 1,961 Total $ 58,173 $ 12 $ ( 4 ) $ 58,181
Schedule of Accrued Expenses	Accrued expenses consisted of the following (in thousands): March 31, December 31, 2021 2020 Accrued payroll and other employee benefits $ 1,104 $ 1,870 Clinical studies 1,081 493 Other accruals 235 307 Preclinical studies 102 72 Accrued interest 71 71 Total accrued expenses $ 2,593 $ 2,813

Notes Payable (Tables)

Notes Payable (Tables)	3 Months Ended
	Mar. 31, 2021
Debt Disclosure [Abstract]
Schedule of Aggregate Carrying Amounts of Term Loans	The aggregate carrying amounts of the Term Loans are comprised of the following (in thousands): March 31, December 31, 2021 2020 Principal $ 10,000 $ 10,000 Add: accreted liability for Final Payment fee 211 176 Less: unamortized discount ( 205 ) ( 235 ) Total $ 10,006 $ 9,941
Schedule Future Maturities of Term Loans, Including Final Payment Fee	Future maturities of the Term Loans, including the Final Payment fee, as of March 31, 2021 are as follows (in thousands): March 31, 2021 Remainder of 2021 $ 1,667 Year ending December 31, 2022 3,333 Year ending December 31, 2023 3,333 Year ending December 31, 2024 2,117 10,450 Unaccreted balance for Final Payment fee on Term Loans ( 239 ) Unamortized discounts ( 205 ) 10,006 Less current portion ( 2,500 ) Noncurrent portion $ 7,506

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	3 Months Ended
	Mar. 31, 2021
Equity [Abstract]
Summary of Stock Option Activity	The following table summarizes the stock option activity during the three months ended March 31, 2021: Shares Weighted- Weighted Aggregate Options outstanding at December 31, 2020 2,463,317 $ 3.71 Granted 1,493,500 $ 5.14 Exercised ( 1,458 ) $ 2.45 Forfeitures and cancellations ( 8,542 ) $ 3.96 Options outstanding at March 31, 2021 3,946,817 $ 4.25 8.51 $ 11,473 Options exercisable at March 31, 2021 1,210,431 $ 3.48 6.83 $ 4,453 (a) Aggregate intrinsic value in this table was calculated as the positive difference, if any, between the closing price per share of the Company’s common stock on March 31, 2021 of $ 7.15 and the price of the underlying options. At March 31, 2021, unamortized stock compensation for stock options was $ 11.0 million, with a weighted-average recognition period of 2.9 years.
Summary of Non-cash Stock-based Compensation Expense	The non-cash stock-based compensation expense for all stock awards, net of forfeitures recognized as they occur, that was recognized in the condensed consolidated statements of operations is as follows (in thousands): Three Months Ended 2021 2020 Research and development $ 474 $ 414 General and administrative 570 373 Total $ 1,044 $ 787
Summary of Reserved Shares of Common Stock for Future Issuance	Common stock reserved for future issuance at March 31, 2021 is as follows: March 31, December 31, 2021 2020 Stock options issued and outstanding 3,946,817 2,463,317 Warrants for common stock 1,366,141 80,428 Awards available under the 2018 Equity Incentive Plan 792,228 1,039,531 Employee stock purchase plan 860,060 612,529 Total 6,965,246 4,195,805

Organization and Accounting P_2

Organization and Accounting Pronouncements - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Date of incorporation	Mar. 16, 2017
State of incorporation	DE
Cash, Cash equivalents and short-term investments	$ 104.1
Foreign currency transaction net realized and unrealized gains (losses)	$ 0.1	$ 0.3

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Additional Information (Details)	3 Months Ended
	Mar. 31, 2021AUD ($)
Maximum | Australian Taxation Office | Australian Research and Development Tax Incentive Program
Summary Of Significant Accounting Policies [Line Items]
Revenue for availability of research and development tax incentive	$ 20,000,000

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Summary of Potentially Dilutive Securities Not Included in Calculation of Diluted Net Loss Per Share (Details) - shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities not included in calculation of diluted net loss per share	5,312,958	2,094,521
Common Stock Options
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities not included in calculation of diluted net loss per share	3,946,817	2,014,093
Common Stock Warrants
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities not included in calculation of diluted net loss per share	1,366,141	80,428

Fair Value of Financial Instr_3

Fair Value of Financial Instruments - Summary of Assets that Require Fair Value Measurements on Recurring Basis and Their Respective Input Levels Based on Fair Value Hierarchy (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total short-term investments	$ 53,218	$ 58,181
U.S. Treasury Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total short-term investments	52,727	56,220
Certificates of Deposit
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total short-term investments	491	1,961
Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total short-term investments	53,218	58,181
Level 1 | U.S. Treasury Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total short-term investments	52,727	56,220
Level 1 | Certificates of Deposit
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total short-term investments	$ 491	$ 1,961

Fair Value of Financial Instr_4

Fair Value of Financial Instruments - Additional Information (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Carrying amount of notes payable	$ 10
Fair Value Measured Using Net Asset Value | Money Market Funds
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Investments in money market funds	$ 42.4	$ 17.4

Certain Financial Statement C_3

Certain Financial Statement Caption Information - Schedule of Company's Short-Term Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 53,213	$ 58,173
Unrealized Gains	6	12
Unrealized losses	(1)	(4)
Short-term investments	53,218	58,181
U.S. Treasury Securities Maturing in One Year or Less
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	50,165	56,218
Unrealized Gains	5	6
Unrealized losses		(4)
Short-term investments	$ 50,170	$ 56,220
U.S. Treasury Securities Maturing in One Year or Less | Maximum
Schedule Of Available For Sale Securities [Line Items]
Maturity (in years)	1 year	1 year
Certificates of Deposit Maturing in One Year or Less
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 490	$ 1,955
Unrealized Gains	1	6
Short-term investments	$ 491	$ 1,961
Certificates of Deposit Maturing in One Year or Less | Maximum
Schedule Of Available For Sale Securities [Line Items]
Maturity (in years)	1 year	1 year
U.S. Treasury Securities Maturing between One and Five years
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 2,558
Unrealized losses	(1)
Short-term investments	$ 2,557
U.S. Treasury Securities Maturing between One and Five years | Minimum
Schedule Of Available For Sale Securities [Line Items]
Maturity (in years)	1 year
U.S. Treasury Securities Maturing between One and Five years | Maximum
Schedule Of Available For Sale Securities [Line Items]
Maturity (in years)	5 years

Certain Financial Statement C_4

Certain Financial Statement Caption Information - Additional information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Schedule Of Available For Sale Securities [Line Items]
Other than temporary impairment loss investments available for sale securities	$ 0	$ 0
Realized gain on investments	$ 0	$ 13,000
Minimum
Schedule Of Available For Sale Securities [Line Items]
Available for sale Securities debt maturities period	1 year
Maximum
Schedule Of Available For Sale Securities [Line Items]
Available for sale Securities debt maturities period	2 years

Certain Financial Statement C_5

Certain Financial Statement Caption Information - Schedule of Accrued Expenses (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Accrued Liabilities Current [Abstract]
Accrued payroll and other employee benefits	$ 1,104	$ 1,870
Clinical studies	1,081	493
Other accruals	235	307
Preclinical studies	102	72
Accrued interest	71	71
Total accrued expenses	$ 2,593	$ 2,813

Notes Payable - Additional Info

Notes Payable - Additional Information (Details) $ / shares in Units, $ in Millions	1 Months Ended
	Sep. 30, 2019USD ($)yrInstallment$ / sharesshares	Apr. 23, 2021	Dec. 31, 2020USD ($)
Short Term Debt [Line Items]
Term Loan maturity date	Jun. 1, 2024
Fair value of the warrants at the date of issuance	$ 0.3
Expected Term
Short Term Debt [Line Items]
Warrants and rights outstanding, measurement input | yr	10
Volatility
Short Term Debt [Line Items]
Warrants and rights outstanding, measurement input	92.78
Risk Free Rate
Short Term Debt [Line Items]
Warrants and rights outstanding, measurement input	1.68
Expected Dividend
Short Term Debt [Line Items]
Warrants and rights outstanding, measurement input	0
Line of Credit
Short Term Debt [Line Items]
Debt instrument, frequency of periodic payment	monthly
Debt instrument, interest rate, basis for effective rate	prime rate
Percentage of final principal payment	4.50%
Required notice period for debt prepayment	30 days
Debt prepayment fee as percent on year one	3.00%
Debt prepayment fee as percent on year two	2.00%
Debt prepayment fee as percent from year three	1.00%
Debt issuance costs	$ 0.1
Debt instrument, interest rate, effective percentage	10.97%
Line of Credit | Prime Rate
Short Term Debt [Line Items]
Debt instrument, basis spread on variable rate	3.00%
Line of Credit | Minimum
Short Term Debt [Line Items]
Debt instrument, interest rate, stated percentage	8.25%
Loan Agreement
Short Term Debt [Line Items]
Borrowing capacity under loan agreement	$ 20
Additional funding not eligible			$ 10
Loan Agreement | Minimum | Subsequent Event
Short Term Debt [Line Items]
Debt instrument, interest rate, effective percentage		4.50%
Loan Agreement | Maximum | Subsequent Event
Short Term Debt [Line Items]
Debt instrument, interest rate, effective percentage		5.00%
Term A Loan
Short Term Debt [Line Items]
Borrowings under loan agreement	$ 10
Line of credit facility frequency of payments principal and interest | Installment	36
Lenders warrants exercisable for shares | shares	80,428
Warrants exercisable, per share exercise price | $ / shares	$ 3.73
Term B Loan
Short Term Debt [Line Items]
Borrowing capacity under loan agreement	$ 5
Percentage of lenders additional warrants to purchase shares of company's common stock	3.00%
Term C Loan
Short Term Debt [Line Items]
Borrowing capacity under loan agreement	$ 5
Percentage of lenders additional warrants to purchase shares of company's common stock	3.00%
Term A Loan & Term B Loan
Short Term Debt [Line Items]
Line of credit facility frequency of payments principal and interest | Installment	30

Notes Payable - Schedule of Agg

Notes Payable - Schedule of Aggregate Carrying Amounts of Term Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Less: unamortized discount	$ (205)
Total	10,006
Line of Credit
Debt Instrument [Line Items]
Principal	10,000	$ 10,000
Add: accreted liability for Final Payment fee	211	176
Less: unamortized discount	(205)	(235)
Total	$ 10,006	$ 9,941

Notes Payable - Schedule Future

Notes Payable - Schedule Future Maturities of Term Loans, Including Final Payment Fee (Details) $ in Thousands	Mar. 31, 2021USD ($)
Debt Disclosure [Abstract]
Remainder of 2021	$ 1,667
Year ending December 31, 2022	3,333
Year ending December 31, 2023	3,333
Year ending December 31, 2024	2,117
Debt instrument carrying amount including unaccreted liability for final payment fee	10,450
Unaccreted balance for Final Payment fee on Term Loans	(239)
Less: unamortized discount	(205)
Total	10,006
Less current portion	(2,500)
Noncurrent portion	$ 7,506

Collaboration And License Agr_2

Collaboration And License Agreements - Additional Information (Details) - Biocon - USD ($)	1 Months Ended	31 Months Ended
	May 31, 2017	Nov. 30, 2019
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Common stock shares issued		2,316,134
Collaboration and License Agreement | Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Regulatory milestone payments	$ 30,000,000
Sales milestone payments	$ 565,000,000

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Details)	Feb. 03, 2021USD ($)Investor$ / sharesshares	Jul. 14, 2020USD ($)	May 02, 2021shares	Mar. 27, 2021USD ($)shares	Aug. 31, 2020USD ($)$ / sharesshares	Sep. 30, 2019	Mar. 31, 2021USD ($)$ / sharesshares	Mar. 31, 2020USD ($)shares	Dec. 31, 2020$ / sharesshares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, shares authorized | shares							200,000,000		200,000,000
Common stock, par value | $ / shares							$ 0.0001		$ 0.0001
Preferred stock, shares authorized | shares							10,000,000
Preferred stock, par value | $ / shares							$ 0.0001
Common stock, shares outstanding | shares							29,040,270		24,753,102
Stock-based compensation expense							$ 1,044,000	$ 787,000
Unamortized stock compensation for stock options							$ 11,000
Weighted-average recognition period of stock option unamortized							2 years 10 months 24 days
Employee Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Repricing of outstanding options | shares							3,946,817		2,463,317
Exercise price of repriced options per share | $ / shares							$ 2.45
Retention stock options issued to purchase common shares | shares							1,493,500
Equity Unit Purchase Agreements
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number Of Institutional Investors | Investor	2
Shares upon exercise of warrants | shares	1,285,713
Gross Proceeds From Issuance Of Common Stock	$ 30,000,000
Gross proceeds from issuance of common stock	30,000,000
Proceeds from issuance of common stock	$ 29,900,000
2019 ATM Facility
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Commission rate						3.00%
Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issuance of common stock, Shares | shares								83,662
Common Stock | Purchase Agreement | Lincoln Park Capital Fund, LLC
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issuance of common stock, Shares | shares			0	65,374
Stock issuance costs				$ 400,000
Estimated maximum amount of common stock issuable				$ 15,000,000
Term of purchase agreement				36 months
Fair market value of commitment shares				$ 200,000
Common Stock | Underwritten Public Offering [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issuance of common stock, Shares | shares					5,461,169
Gross Proceeds From Issuance Of Common Stock					$ 38,200,000
Sale of stock, price per share | $ / shares					$ 7
Gross proceeds from issuance of common stock					$ 38,200,000
Proceeds from issuance of common stock					$ 35,700,000
Common Stock | Over-Allotment Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issuance of common stock, Shares | shares					461,169
Common Stock | Equity Unit Purchase Agreements
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issuance of common stock, Shares | shares	4,285,710
Common Stock | 2019 ATM Facility
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issuance of common stock, Shares | shares							174,649
Proceeds from issuance of common stock							$ 800,000
Common stock shares maximum aggregate offering price							$ 8,450
Common Stock | 2020 ATM Facility
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issuance of common stock, Shares | shares			0				788,685
Gross Proceeds From Issuance Of Common Stock							$ 10,400,000
Gross proceeds from issuance of common stock							10,400,000
Proceeds from issuance of common stock							10,000,000
Common stock shares maximum aggregate offering price		$ 150,000,000
Stock issuance costs							$ 400,000
Common Stock Warrants | Equity Unit Purchase Agreements
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Gross Proceeds From Issuance Of Common Stock	$ 25,000,000
Sale of stock, price per share | $ / shares	$ 25
Gross proceeds from issuance of common stock	$ 25,000,000
Warrants exercisable, per share exercise price | $ / shares	$ 14

Stockholders' Equity - Summary

Stockholders' Equity - Summary of Stock Option Activity (Details) - Stock Options $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2021USD ($)$ / sharesshares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares Subject to Options outstanding, Beginning Balance | shares	2,463,317
Number of Shares Subject to Options, Granted | shares	1,493,500
Number of Shares Subject to Options, Exercised | shares	(1,458)
Number of Shares Subject to Options, Forfeitures and Cancellations | shares	(8,542)
Number of Shares Subject to Options outstanding, Ending Balance | shares	3,946,817
Number of Shares Subject to Options, Exercisable | shares	1,210,431
Weighted- Average Exercise Price Per Share, Beginning Balance | $ / shares	$ 3.71
Weighted- Average Exercise Price Per Share, Granted | $ / shares	5.14
Weighted- Average Exercise Price Per Share, Exercised | $ / shares	2.45
Weighted- Average Exercise Price Per Share, Forfeitures and Cancellations | $ / shares	3.96
Weighted- Average Exercise Price Per Share, Ending Balance | $ / shares	4.25
Weighted- Average Exercise Price Per Share, Exercisable | $ / shares	$ 3.48
Weighted Average Remaining Contractual Term, Options Outstanding	8 years 6 months 3 days
Weighted Average Remaining Contractual Term, Options Exercisable	6 years 9 months 29 days
Aggregate Intrinsic Value, Options Outstanding | $	$ 11,473
Aggregate Intrinsic Value, Options Exercisable | $	$ 4,453

Stockholders' Equity - Summar_2

Stockholders' Equity - Summary of Stock Option Activity (Parenthetical) (Details)	Mar. 31, 2021$ / shares
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Closing stock price per share	$ 7.15

Stockholders' Equity - Summar_3

Stockholders' Equity - Summary of Non-cash Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Non-cash stock-based compensation expense	$ 1,044	$ 787
Research and Development Expense
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Non-cash stock-based compensation expense	474	414
General and Administrative Expense
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Non-cash stock-based compensation expense	$ 570	$ 373

Stockholders' Equity - Summar_4

Stockholders' Equity - Summary of Common Stock Reserved for Future Issuance (Details) - shares	Mar. 31, 2021	Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total common stock reserved for future issuance	6,965,246	4,195,805
Stock Options Issued and Outstanding
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total common stock reserved for future issuance	3,946,817	2,463,317
Warrants for Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total common stock reserved for future issuance	1,366,141	80,428
Awards Available Under 2018 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total common stock reserved for future issuance	792,228	1,039,531
Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total common stock reserved for future issuance	860,060	612,529

Subsequent Events - Additional

Subsequent Events - Additional Information (Details)	Apr. 23, 2021
Loan Agreement | Subsequent Event
Subsequent Event [Line Items]
Loan agreement amended date	Apr. 23, 2021