Forma Therapeutics (FMTX) 10-Q 14 May 21 2021 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2021	Apr. 30, 2021
Cover [Abstract]
Entity Registrant Name	Forma Therapeutics Holdings, Inc.
Document Type	10-Q
Current Fiscal Year End Date	--12-31
Entity Common Stock, Shares Outstanding		47,372,658
Amendment Flag	false
Entity Central Index Key	0001538927
Entity Filer Category	Non-accelerated Filer
Document Period End Date	Mar. 31, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Shell Company	false
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity File Number	001-39333
Entity Incorporation State Country Code	DE
Entity Tax Identification Number	37-1657129
Entity Address Address Line1	500 Arsenal Street
Entity Address, Address Line Two	Suite 100
Entity Address City Or Town	Watertown
Entity Address State Or Province	MA
Entity Address Postal Zip Code	02472
City Area Code	617
Local Phone Number	679-1970
Document Quarterly Report	true
Document Transition Report	false
Security12b Title	Common stock, par value $0.001 per share
Trading Symbol	FMTX
Security Exchange Name	NASDAQ

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (unaudited) - USD ($) $ in Thousands	Dec. 31, 2020	Sep. 30, 2020
Current assets:
Cash and cash equivalents	$ 282,689	$ 97,834
Short-term marketable securities	350,365	452,894
Income tax receivable	15,273	15,066
Prepaid expenses and other current assets	6,120	8,074
Total current assets	654,447	573,868
Property and equipment, net	1,520	1,420
Long-term marketable securities	12,534	52,996
Operating lease right-of-use asset		6,927
Other assets	12,470	15,025
Total assets	680,971	650,236
Current liabilities:
Accounts payable	4,295	2,927
Accrued expenses and other current liabilities	27,104	22,215
Operating lease liability		3,041
Income tax payable	301	374
Total current liabilities	31,700	28,557
Operating lease liability, noncurrent		5,214
Deferred rent, noncurrent	1,027
Total liabilities	32,727	33,771
Commitments and contingencies (Note 9)
Stockholders’ equity:
Common stock, $0.001 par value; 150,000,000 shares authorized at March 31, 2021 and December 31, 2020; 47,366,541 and 47,300,231 shares issued at March 31, 2021 and December 31, 2020, respectively; 47,328,575 and 47,248,685 shares outstanding at March 31, 2021 and December 31, 2020, respectively	47	47
Preferred stock, $0.001 par value; 10,000,000 shares authorized and no issued or outstanding at March 31, 2021 and December 31, 2020
Additional paid-in capital	705,607	709,788
Accumulated deficit	(57,410)	(93,370)
Total stockholders’ equity	648,244	616,465
Total liabilities and stockholders’ equity	$ 680,971	$ 650,236

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (unaudited) (Parenthetical) - $ / shares	Mar. 31, 2021	Dec. 31, 2020
Statement Of Financial Position [Abstract]
Preferred stock par value	$ 0.001	$ 0.001
Preferred stock shares authorized	10,000,000	10,000,000
Preferred stock shares issued	0	0
Preferred stock shares outstanding	0	0
Common stock par value	$ 0.001	$ 0.001
Common stock shares authorized	150,000,000	150,000,000
Common stock shares issued	47,366,541	47,300,231
Common stock shares outstanding	47,328,575	47,248,685

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	$ 26,343	$ 23,210
General and administrative	9,867	8,933
Restructuring charges		83
Total operating expenses	36,210	32,226
Loss from operations	(36,210)	(32,226)
Other income:
Gain on Hit Discovery divestiture		23,312
Interest income	262	641
Other (expense) income, net	(4)	18
Total other income, net	258	23,971
Loss before taxes	(35,952)	(8,255)
Income tax expense (benefit)	8	(19,485)
Net (loss) income and comprehensive (loss) income	(35,960)	11,230
Undistributed earnings allocable to participating securities		(3,456)
Net (loss) income allocable to shares of common stock, basic	(35,960)	5,838
Change in fair value attributable to warrants to purchase Series B-3 convertible preferred stock		(20)
Net (loss) income allocable to shares of common stock, diluted	$ (35,960)	$ 7,754
Net (loss) income per share of common stock:
Basic	$ (0.76)	$ 2.29
Diluted	$ (0.76)	$ 0.36
Weighted-average shares of common stock outstanding:
Basic	47,295,013	2,548,079
Diluted	47,295,013	21,392,760
Series D Preferred Stock
Other income:
Accretion of cumulative dividends on Series D redeemable convertible preferred stock		$ (1,936)
Accretion of cumulative dividends on Series D redeemable convertible preferred stock		1,936
Series B3 Preferred Stock
Other income:
Change in fair value attributable to warrants to purchase Series B-3 convertible preferred stock		$ (20)

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Redeemable Convertible and Convertible Preferred Stock and Stockholders' Equity (Deficit) (unaudited) - USD ($) $ in Thousands	Total	Series A Convertible Preferred Stock [Member]	Series B-1 Convertible Preferred Stock [Member]	Series B-2 Convertible Preferred Stock [Member]	Series D Redeemable Convertible Preferred Stock [Member]	Series C Convertible Preferred Stock [Member]	Common Stock	Enterprise Junior Stock [Member]	Additional Paid-In Capital [Member]	(Accumulated Deficit) Retained Earnings [Member]
Balance at Dec. 31, 2019	$ 18,246								$ 1,116	$ 16,740
Temporary equity balance, Shares at Dec. 31, 2019		2,304,815	14,921,676	8,790,249	53,593,440	6,452,619	2,250,696	2,597,091
Temporary equity balance, Value at Dec. 31, 2019		$ 4,656	$ 20,907	$ 12,272	$ 100,296	$ 385	$ 2	$ 3
Accretion of cumulative dividends on Series D redeemable convertible preferred stock	(1,936)				$ 1,936					(1,936)
Exercise of options to purchase common stock	3								3
Exercise of options to purchase common stock, Shares							496
Exercise of warrant to purchase common stock	12								12
Exercise of warrant to purchase common stock, Shares							297,241
Equity-based compensation	1,210								1,210
Net income and comprehensive income	11,230									11,230
Balance at Mar. 31, 2020	28,765								2,341	26,034
Temporary equity balance, Shares at Mar. 31, 2020		2,304,815	14,921,676	8,790,249	53,593,440	6,452,619	2,548,433	2,635,430
Temporary equity balance, Value at Mar. 31, 2020		$ 4,656	$ 20,907	$ 12,272	$ 102,232	$ 385	$ 2	$ 3
Equity-based compensation, Shares								38,339
Balance at Dec. 31, 2020	648,244								705,607	(57,410)
Temporary equity balance, Shares at Dec. 31, 2020							47,248,685
Temporary equity balance, Value at Dec. 31, 2020							$ 47
Exercise of options to purchase common stock	$ 333								333
Exercise of options to purchase common stock, Shares	68,389						68,389
Vesting of restricted common stock, Shares							11,501
Equity-based compensation	$ 3,848								3,848
Net income and comprehensive income	(35,960)									(35,960)
Balance at Mar. 31, 2021	616,465								$ 709,788	$ (93,370)
Temporary equity balance, Shares at Mar. 31, 2021							47,328,575
Temporary equity balance, Value at Mar. 31, 2021	$ 140,452						$ 47

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows (unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash flows from operating activities
Net (loss) income	$ (35,960)	$ 11,230
Adjustments to reconcile net (loss) income to net cash used in operating activities:
Depreciation and amortization	183	543
Non-cash operating lease expense	375
Equity-based compensation	3,848	1,210
Change in fair value of warrant liability		(20)
Amortization (accretion) of marketable securities	377	(27)
Gain on Hit Discovery divestiture		(23,312)
Changes in operating assets and liabilities:
Decrease in accounts receivable		227
(Increase) in income taxes receivable	207	(19,486)
(Increase) in prepaid expenses and other current assets	(1,954)	(1,192)
(Increase) in other assets	(2,555)
(Decrease) in accounts payable	(1,368)	(1,420)
(Decrease) in accrued expenses and other current liabilities	(3,990)	(958)
Increase in income taxes payable	73
(Decrease) in operating lease liability	(473)	(97)
Net cash used in operating activities	(41,237)	(33,419)
Cash flows from investing activities
Purchases of held-to-maturity marketable securities	(257,868)	(32,080)
Proceeds from maturity of marketable securities	114,500
Purchases of property and equipment	(83)	(78)
Net proceeds from Hit Discovery divestiture	17,500
Net cash used in investing activities	(143,451)	(29,318)
Cash flows from financing activities
Proceeds from exercise of warrant to purchase common stock		12
Proceeds from exercise of options to purchase common stock	333	3
Payment of public offering costs	(500)	(11)
Net cash used in financing activities	(167)	(235)
Net decrease in cash, cash equivalents and restricted cash	(184,855)	(62,972)
Cash, cash equivalents and restricted cash, beginning of the period	285,159	173,796
Cash, cash equivalents and restricted cash, end of the period	100,304	110,824
Supplemental disclosure of non-cash activities:
Operating lease right-of-use asset recognized upon adoption of Topic 842	$ 7,478
Accretion of preferred return and cumulative dividends on preferred securities		1,936
Deferred offering costs in accounts payable and accrued expenses and other current liabilities		1,025
Installment Receivable, current and noncurrent, in prepaid expenses and other current assets and other assets (Note 17)		12,710
Equity Consideration in other assets (Note 17)		10,000
Series D Redeemable Convertible Preferred Stock [Member]
Cash flows from financing activities
Payment of issuance costs on Series D redeemable convertible preferred stock		(239)
Supplemental disclosure of non-cash activities:
Deferred issuance costs on Series D redeemable convertible preferred stock in accruals		20
Valo Health [Member]
Adjustments to reconcile net (loss) income to net cash used in operating activities:
Interest income on future cash payments from Valo Health		(117)
Hit Discovery Divestiture [Member]
Cash flows from investing activities
Net proceeds from Hit Discovery divestiture		$ 2,840

Organization and Nature of Busi

Organization and Nature of Business	3 Months Ended
	Mar. 31, 2021
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Organization and Nature of Business	Note 1—Organization and Nature of Business On October 2, 2019, Forma Therapeutics Holdings, LLC, a Delaware limited liability company formed in December 2011, was reorganized into Forma Therapeutics Holdings, Inc. Forma Therapeutics Holdings, Inc. and its wholly-owned subsidiaries, hereinafter collectively, “the Company”, is a clinical-stage biopharmaceutical company focused on the development and commercialization of novel therapeutics to transform the lives of patients with rare hematologic diseases and cancers. On June 23, 2020, the Company completed an initial public offering (“IPO”) in which the Company issued and sold 15,964,704 shares of its common stock at a public offering price of $20.00 per share, including 2,082,352 shares of common stock sold pursuant to the underwriters’ exercise of their option to purchase additional shares of common stock, for aggregate gross proceeds of $319.3 million. The Company raised approximately $293.3 million in net proceeds after deducting underwriting discounts and commissions and offering expenses payable by the Company. Upon the closing of the IPO, all of the outstanding shares of Series A convertible preferred stock (“Series A Preferred Stock”), Series B-1 convertible preferred stock (“Series B-1 Preferred Stock”), Series B-2 convertible preferred stock (“Series B-2 Preferred Stock”), Series C convertible preferred stock (“Series C Preferred Stock”), and Series D redeemable convertible preferred stock (“Series D Preferred Stock”) automatically converted into 20,349,223 shares of common stock; all issued shares of enterprise junior stock automatically converted into 2,124,845 and 103,007 shares of common stock and restricted common stock, respectively; and warrants to purchase an aggregate of 299,999 shares of Series B-3 convertible preferred stock (“Series B-3 Preferred Stock”, collectively with the Series A, Series B-1, Series B-2, Series C, and Series D Preferred Stock, “Preferred Stock”) with an exercise price of $1.20 per share automatically converted into warrants to purchase an aggregate of 70,133 shares of common stock with an exercise price of $5.13 per share. Subsequent to the closing of the IPO, there were no shares of preferred stock or enterprise junior stock outstanding. In connection with the closing of the IPO, the Company filed a second amended and restated certificate of incorporation (“Second Amended Certificate of Incorporation”) to change the authorized capital stock to 160,000,000 shares of which 147,494,175 are designated as voting common stock, 2,505,825 are designated as non-voting common stock and 10,000,000 are designated as undesignated preferred stock, all with a par value of $0.001 per share. On December 15, 2020, the Company completed a follow-on public offering in which the Company issued and sold 6,095,000 shares of its common stock at a public offering price of $45.25 per share, including 795,000 shares of common stock sold pursuant to the underwriters’ exercise of their option to purchase additional shares of common stock, for aggregate gross proceeds of $275.8 million. The Company raised approximately $258.6 million in net proceeds after deducting underwriting discounts and commissions and offering expenses payable by the Company. Liquidity The Company is focused on the development and commercialization of novel therapeutics to transform the lives of patients with rare hematologic diseases and cancers. The Company is building a pipeline of therapeutics with a focus on these areas and has devoted substantially all of its resources to the research and development of its drug development efforts, comprised of research and development, manufacturing, conducting clinical trials, protecting its intellectual property and general and administrative functions relating to these operations. The future success of the Company is dependent on its ability to develop its product candidates and ultimately upon its ability to attain sustained profitable operations through commercialization of products. The Company is subject to risks common to companies in the biotechnology industry, including but not limited to, the need for additional capital, risks of failure of preclinical studies and clinical trials, the need to obtain marketing approval and reimbursement for any drug product candidate that it may identify and develop, the need to successfully commercialize and gain market acceptance of its product candidates, dependence on key personnel, protection of proprietary technology, compliance with government regulations, development of technological innovations by competitors, reliance on third-party manufacturers and the ability to transition from pilot-scale production to large-scale manufacturing of products. The Company has determined that its cash, cash equivalents and marketable securities of $603.7 million as of March 31, 2021 will be sufficient to fund its operations for at least one year from the date these condensed consolidated financial statements are issued. To date, the Company has primarily financed its operations through license and collaboration agreements, the sale of preferred shares and preferred stock to outside investors and the completion of the IPO and follow-on public offering. The Company has experienced significant negative cash flows from operations during the three months ended March 31, 2021. The Company does not expect to experience any significant positive cash flows from its existing collaboration agreements and does not expect to have any product revenue in the near term. The Company expects to incur substantial operating losses and negative cash flows from operations for the foreseeable future as it continues to invest significantly in research and development of its programs. Management’s belief with respect to its ability to fund operations is based on estimates that are subject to risks and uncertainties. If actual results are different from management’s estimates, the Company may need to seek additional funding sooner than would otherwise be expected. There can be no assurance that the Company will be able to obtain additional funding on acceptable terms, if at all.

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Note 2—Summary of Significant Accounting Policies Basis of Presentation and Consolidation The condensed consolidated financial statements include the accounts of Forma Therapeutics Holdings, Inc. and its wholly owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation. The Company has prepared the accompanying condensed consolidated financial statements in conformity with accounting principles generally accepted in the United States of America (“GAAP”) and pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). Certain information and footnote disclosures generally included in financial statements in conformity with GAAP have been condensed or omitted in accordance with such rules and regulations. Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standard Updates (“ASU”) of the Financial Accounting Standards Board (“FASB”). Significant Accounting Policies These condensed consolidated financial statements should be read in conjunction with the Company’s consolidated financial statements and the notes thereto included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2020. Unaudited Interim Condensed Consolidated Financial Statements The accompanying condensed consolidated balance sheet as of March 31, 2021, the condensed consolidated statements of operations and comprehensive (loss) income for the three months ended March 31, 2021 and 2020, the condensed consolidated statements of redeemable convertible and convertible preferred stock and stockholders’ equity (deficit) for the three months ended March 31, 2021 and 2020 and the condensed consolidated statements of cash flows for the three months ended March 31, 2021 and 2020 are unaudited. The financial data and other information contained in the notes thereto as of March 31, 2021 and for the three months ended March 31, 2021 and 2020 are also unaudited. The condensed consolidated balance sheet data as of December 31, 2020 was derived from the Company’s audited consolidated financial statements included in the Annual Report on Form 10-K for the fiscal year ended December 31, 2020. With the exception of the adoption of ASU No. 2016-02, Leases (Topic 842) Cash, Cash Equivalents and Restricted Cash The Company considers all short-term, highly liquid investments with original maturities of 90 days or less at acquisition date to be cash equivalents. The carrying amounts of the Company’s cash equivalents approximate their fair value due to their short-term nature. Amounts in restricted cash consist of letters of credit to secure the Company’s facilities, including its new lease for office and laboratory space entered into in September 2020 (see Note 7). Restricted cash is included in other assets on the condensed consolidated balance sheets. The following table reconciles cash, cash equivalents and restricted cash as of March 31, 2021 and 2020 to the condensed consolidated statements of cash flows (in thousands): March 31, 2021 2020 Cash and cash equivalents $ 97,834 $ 110,329 Restricted cash 2,470 495 Total cash, cash equivalents and restricted cash as shown in the condensed consolidated statements of cash flows $ 100,304 $ 110,824 Marketable Securities Marketable securities generally consist of U.S. Treasury securities, debt securities of U.S. government agencies and corporate entities and commercial paper. The objectives for holding investments are to invest the Company’s excess cash resources in investment vehicles that provide a better rate of return compared to an interest-bearing bank account with limited risk to the principal invested. Marketable securities with original maturities of greater than 90 days and remaining maturities of less than one year from the balance sheet date are classified as short-term marketable securities. Marketable securities with remaining maturities of greater than one year from the balance sheet date are classified as long-term marketable securities. All investments are classified as held-to-maturity marketable securities as the Company does not have intent to sell these securities and it is more likely than not the Company will not be required to sell such investments before recovery of their amortized cost basis. Held-to-maturity securities are stated at their amortized cost, adjusted for amortization of premiums and accretion of discounts to maturity. Such amortization and accretion is included in interest income in the condensed consolidated statements of operations and comprehensive (loss) income. Comprehensive (Loss) Income Comprehensive (loss) income includes net (loss) income as well as other changes in stockholders’ equity that result from transactions and economic events other than those with the equity holders. There was no difference between net (loss) income and comprehensive (loss) income presented in the accompanying condensed consolidated financial statements for the three months ended March 31, 2021 and 2020. Equity-Based Compensation The Company accounts for equity awards, including grants of enterprise incentive shares, enterprise junior stock, stock options, restricted stock units and restricted common stock, in accordance with ASC 718, Compensation – Stock Compensation Subsequent to the IPO, the fair value of the Company’s common stock underlying its equity awards is based on the quoted market price of the Company’s common stock on the grant date. The Company estimates the fair value of stock options using the Black-Scholes option pricing model, which uses as inputs the fair value of the Company’s common stock, and certain management estimates, including the expected stock price volatility, the expected term of the award, the risk-free rate, and expected dividends. Expected volatility is calculated based on reported volatility data for a representative group of publicly traded companies for which historical information is available. The Company selects companies with comparable characteristics with historical share price information that approximates the expected term of the equity-based awards. The Company computes the historical volatility data using the daily closing prices for the selected companies’ shares during the equivalent period that approximates the calculated expected term of the stock options. The Company will continue to apply this method until a sufficient amount of historical information regarding the volatility of its stock price becomes available. The risk-free interest rate is based on the U.S. Treasury yield curve in effect at the time of grant commensurate with the expected term assumption. The Company uses the simplified method, under which the expected term is presumed to be the midpoint between the vesting date and the end of the contractual term. The Company utilizes this method due to lack of historical exercise data. The expected dividend yield is assumed to be zero as the Company has no current plans to pay any dividends on common stock. Prior to the IPO, for awards granted in the first quarter of 2020, the Company used a probability-weighted expected returns method (“PWERM”) with four scenarios to value the common stock underlying the awards: an IPO, a delayed IPO, a sale of the Company and a remain private scenario. In the IPO and sale scenarios, the Company estimated an equity value based on the guideline public company method under a market approach. The guideline public companies consisted of biopharmaceutical companies with recently completed initial public offerings. For the remain private scenario, the Company back-solved to the price of a recently issued preferred security. The Company converted its estimated future value in each scenario to present value using a risk-adjusted discount rate. The relative probability of each scenario was determined based on an assessment of then-current market conditions. Where appropriate, the Company applied a discount for lack of marketability to the value indicated for the common stock. The valuation methodology used to value the common stock prior to the IPO included estimates and assumptions that required the Company’s judgment. Significant changes to the key assumptions used in the valuations could have resulted in different fair values of the Company’s common stock at each valuation date. For awards with service-based vesting conditions, the Company recognizes equity-based compensation expense on a straight-line basis over the vesting period. For awards subject to performance conditions, the Company recognizes equity-based compensation expense using an accelerated recognition method over the remaining service period when the Company determines the achievement of the performance condition is probable. The Company classifies equity-based compensation expense in its condensed consolidated statements of operations and comprehensive (loss) income consistent with the classification of the award recipient’s compensation expense. Leases Effective January 1, 2021, the Company adopted Topic 842 using the required modified retrospective approach and utilizing the effective date as its date of initial application. As a result, prior periods are presented in accordance with the previous guidance in ASC 840, Leases The Company evaluates whether an arrangement is or contains a lease at the inception date. If determined to be or contain a lease, the Company determines the classification of the lease at the commencement date, which represents the date at which the lessor makes the underlying asset available for use by the Company. When determining the expected accounting lease term, the Company includes the noncancellable lease term, together with periods covered by (i) an option to extend the lease if the Company is reasonably certain to exercise such option, (ii) an option to terminate the lease if the Company is reasonably certain not to exercise such option and (iii) an option to extend or not terminate the lease where the exercise of such option is controlled by the lessor. The Company has elected the short-term lease exemption, which allows the Company to not recognize lease liabilities and right-of-use assets arising from lease arrangements with original lease terms of twelve months or less. The Company elected the practical expedient to not separate lease and non-lease components for its real estate leases. Right-of-use assets represent the Company’s right to use an underlying asset over the lease term and lease liabilities represent the Company’s obligation to make lease payments under the arrangement. The Company measures its lease liabilities as the present value of the lease payments, discounted using an incremental borrowing rate, as interest rates implicit in lease arrangements are generally not readily determinable. The Company measures its right-of-use assets as the present value of its lease payments at the commencement date, adjusted for prepaid rent payments and tenant incentives. The incremental borrowing rate represents the interest rate at which the Company could borrow an amount equal to the lease payments on a fully collateralized basis, over a similar term, in a similar economic environment. The Company recognizes rent expense for operating leases on a straight-line basis. The Company recognizes variable lease expenses as incurred. The Company remeasures right-of-use assets and lease liabilities when a lease is modified, and the modification is not accounted for as a separate contract. A modification is accounted for as a separate contract if the modification grants the Company an additional right of use not included in the original lease arrangement and the increase in lease payments is commensurate with the additional right of use. The Company assesses its right-of-use assets for impairment in a manner consistent with its assessment for long-lived assets held and used in operations. Recently Adopted Accounting Pronouncements In February 2016, the FASB Topic 842 which supersedes the existing guidance for lease accounting. The FASB has issued several updates to the standard which: (i) clarify how to apply certain aspects of the new standard; (ii) provide an additional transition method for adoption of the new standard; (iii) provide a practical expedient for certain lessor accounting; and (iv) amend certain narrow aspects of the guidance. Topic 842 requires the identification and classification of arrangements that are or contain a lease. In general, for lease arrangements exceeding a twelve-month term, these arrangements must be recognized as assets and liabilities on the balance sheet of the lessee. Under Topic 842, a right-of-use asset and lease obligation will be recorded for all leases, whether operating or financing, while the income statement will reflect lease expense for operating leases and amortization/interest expense for financing leases. The balance sheet amount recorded for existing leases at the date of adoption of Topic 842 is calculated using the applicable incremental borrowing rate at the date of adoption. Topic 842 is effective for the Company on January 1, 2022, with early adoption permitted. The Company elected to early adopt the new standard and used the modified retrospective approach effective January 1, 2021 as the initial date of application. The Company elected the available package of practical expedients which allowed the Company to not reassess previous accounting conclusions around whether arrangements are or contain leases, the classification of leases, and the treatment of initial direct costs. As a result of the adoption of Topic 842, the Company recorded (i) an operating lease liability of $8.9 million and (ii) an operating lease right-of-use asset of $7.5 million, net of the unamortized balance of deferred rent liability and tenant improvement allowances as of the transition date. There was no impact to the Company’s results of operations and cash flows from operations. A summary of the impact of the adoption is as follows (in thousands): December 31, 2020 Impact of Adoption January 1, 2021 Operating lease right-of-use asset $ — $ 7,478 $ 7,478 Accrued expenses and other current liabilities 27,104 (399 ) 26,705 Operating lease liability, current — 3,025 3,025 Deferred rent, noncurrent 1,027 (1,027 ) — Operating lease liability, noncurrent — 5,879 5,879

Fair Value of Financial Assets

Fair Value of Financial Assets and Liabilities	3 Months Ended
	Mar. 31, 2021
Fair Value Disclosures [Abstract]
Fair Value of Financial Assets and Liabilities	Note 3—Fair Value of Financial Assets and Liabilities The following tables present information about the Company’s assets that are measured or disclosed at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values (in thousands): Fair Value Measurements at the Reporting Date Using March 31, 2021 Quoted Prices In Active Markets Using Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets—Cash equivalents Repurchase agreement $ 12,000 $ — $ 12,000 $ — Money market funds 62,993 62,993 — — Commercial paper 19,999 — 19,999 — Assets—Short-term marketable securities U.S. Government agency securities 61,708 — 61,708 — U.S. Treasury securities 21,209 21,209 — — Commercial paper 330,550 — 330,550 — Corporate debt securities 39,468 — 39,468 — Assets—Long-term marketable securities U.S. Government agency securities 29,981 — 29,981 — U.S. Treasury securities 23,003 23,003 — — Total $ 600,911 $ 107,205 $ 493,706 $ — Fair Value Measurements at the Reporting Date Using December 31, 2020 Quoted Prices In Active Markets Using Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets—Cash equivalents Repurchase agreement $ 12,000 $ — $ 12,000 $ — Commercial paper 22,493 — 22,493 — Money market funds 227,987 227,987 — — Assets—Short-term marketable securities U.S. Government agency securities 55,469 — 55,469 — U.S. Treasury securities 38,294 38,294 — — Commercial paper 237,735 — 237,735 — Corporate debt securities 18,873 — 18,873 — Assets—Long-term marketable securities U.S. Government agency securities 7,049 — 7,049 — Corporate debt securities 5,492 — 5,492 — Total $ 625,392 $ 266,281 $ 359,111 $ — During the three months ended March 31, 2021 and three months ended March 31, 2020 there were no transfers into or out of Level 3. During the three months ended March 31, 2020, the Company recognized a gain on the remeasurement of the warrant liability, which was comprised of three warrants to purchase an aggregate of 299,999 shares of Series B-3 Preferred Stock with an exercise price of $1.20 per share (“Series B-3 Preferred Warrants”). The value for the warrant liability balance was based on a Black-Scholes option pricing model using significant inputs not observable in the market representing a Level 3 measurement within the fair value hierarchy. Gains and losses on remeasurement of Level 3 securities are included in other (loss) income, net on the condensed consolidated statements of operations and comprehensive (loss) income. The warrants were exercised in July 2020 and as of March 31, 2021, the Company had no outstanding warrants. The following assumptions were used to determine the fair value of the warrants to purchase Series B-3 Preferred Stock: March 31, 2020 Risk-free interest rate 0.4 % Expected term (in years) 5.3 Expected volatility 72.6 % Expected dividend yield 0.0 % Fair value per share of underlying Series B-3 Preferred Stock $ 1.46 The following table provides a summary of changes in fair value of the Level 3 warrant liability (in thousands): Warrant Liability Balance at December 31, 2019 $ 364 Change in fair value (20 ) Balance at March 31, 2020 $ 344

Marketable Securities

Marketable Securities	3 Months Ended
	Mar. 31, 2021
Investments Debt And Equity Securities [Abstract]
Marketable Securities	Note 4—Marketable Securities The following table presents the carrying amounts and estimated fair values of financial instruments not measured at fair value in the condensed consolidated balance sheets as they are considered held-to-maturity securities. The Company’s investments by type consisted of the following (in thousands): March 31, 2021 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Assets U.S. Government agency securities $ 91,687 $ 17 $ (15 ) $ 91,689 U.S. Treasury securities 44,201 11 — 44,212 Commercial paper 330,520 41 (11 ) 330,550 Corporate debt securities 39,482 — (14 ) 39,468 Total $ 505,890 $ 69 $ (40 ) $ 505,919 December 31, 2020 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Assets U.S. Government agency securities $ 62,508 $ 10 $ — $ 62,518 U.S. Treasury securities 38,287 7 — 38,294 Commercial paper 237,733 18 (16 ) 237,735 Corporate debt securities 24,371 3 (9 ) 24,365 Total $ 362,899 $ 38 $ (25 ) $ 362,912 As marketable securities are considered held-to-maturity, the unrealized gains and losses are not recorded within the condensed consolidated financial statements. As of March 31, 2021 and December 31, 2020, the Company held 28 and 16 investments, respectively, in an unrealized loss position with an aggregate fair value of $191.4 million and $93.7 million, respectively. These investments were in a loss position for less than 12 months and the Company considered the loss to be temporary in nature. The aggregate of individual unrealized losses as of March 31, 2021 and December 31, 2020 was not significant.

Prepaid Expenses and Other Curr

Prepaid Expenses and Other Current Assets	3 Months Ended
	Mar. 31, 2021
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
Prepaid Expenses and Other Current Assets	Note 5—Prepaid Expenses and Other Current Assets Prepaid expenses and other current assets consisted of the following (in thousands): March 31, December 31, 2021 2020 Prepaid expenses $ 6,065 $ 4,793 Other non-trade receivables 2,009 1,327 $ 8,074 $ 6,120

Property and Equipment, Net

Property and Equipment, Net	3 Months Ended
	Mar. 31, 2021
Property Plant And Equipment [Abstract]
Property and Equipment, Net	Note 6—Property and Equipment, Net Property and equipment, net consisted of the following (in thousands): March 31, December 31, 2021 2020 Computer and office equipment $ 2,294 $ 2,253 Software 2,473 2,473 Lab equipment 4,602 4,560 Furniture and fixtures 377 377 Leasehold improvements 3,402 3,402 13,148 13,065 Less: Accumulated depreciation (11,728 ) (11,545 ) $ 1,420 $ 1,520 Depreciation and amortization expense related to property and equipment for the three months ended March 31, 2021 and 2020 totaled $0.2 million and $0.5 million, respectively.

Leases

Leases	3 Months Ended
	Mar. 31, 2021
Leases [Abstract]
Leases	Note 7—Leases The Company’s operating lease activity is primarily comprised of noncancelable facilities leases for office and laboratory space in Watertown, MA and Branford, CT. The Company’s Watertown, MA lease (the “Arsenal Street Lease”) is with a landlord who is an investor and related party of the Company. As amended on September 30, 2017, the Arsenal Street Lease is subject to annual increases to base rent over a term expiring in January 2024. In addition to base rent, monthly rental payments include the Company’s proportionate share of operating expenses. The Arsenal Street Lease included a tenant improvement allowance of $0.5 million, of which the Company has used the entire allowance. The Arsenal Street Lease terms provide for one five-year extension term with base rent calculated on the then-market rate. The Arsenal Street Lease is secured by a letter of credit of $0.5 million that is classified in other assets on the condensed consolidated balance sheets. As amended on January 1, 2018, the Company’s Branford, CT lease is subject to annual increases to base rent over a term expiring in December 2023. The lease included a tenant improvement allowance of $1.0 million, of which $0.1 million remains unused. In addition to base rent, monthly rental payments include the Company’s proportionate share of operating expenses. The lease terms provide for one five-year extension term with base rent calculated on a discounted then-market rate. Pursuant to the Hit Discovery divestiture, the Company’s Branford, CT lease was assigned to and assumed by Valo Health. Valo Health will pay the landlord rental amounts due under the lease including minimum lease payments of $0.6 million, $0.8 million and $0.8 million for the nine months ended December 31, 2021, and years ended December 31, 2022 and 2023, respectively. The Company remains jointly and severally liable for the remaining lease payments under the lease. In the event Valo Health does not make payments under the lease, the Company would be expected to pursue available remedies under the Asset Purchase Agreement (the “Agreement”) executed pursuant to the sale (see Note 17). During the three months ended March 31, 2021, the Company recorded rent expense under the head lease of $0.2 million, offset by sublease income of $0.2 million, both of which are included as components of operating lease cost in the table below. The components of operating lease expense were as follows (in thousands): Three Months Ended March 31, 2021 Operating lease cost $ 468 Variable lease cost 226 $ 694 Supplemental cash flow information related to operating leases was as follows (in thousands): Three Months Ended March 31, 2021 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows related to operating leases $ 564 Future minimum lease payments under noncancellable leases as of March 31, 2021 were as follows (in thousands): Operating Leases 2021 (excluding the three months ended March 31, 2021) $ 2,334 2022 3,177 2023 3,246 2024 197 2025 — Total lease payments 8,954 Present value adjustment (699 ) Present value of operating lease liabilities $ 8,255 As of March 31, 2021, the Company’s operating leases were measured using a weighted-average incremental borrowing rate of 6.0% over a weighted-average remaining lease term of 2.8 years. In September 2020, the Company entered into a new lease for office and laboratory space with the landlord of the Company’s Arsenal Street Lease in Watertown, MA (the “Beacon Street Lease”). The Beacon Street Lease, which includes office and laboratory space, is subject to base rent of $0.3 million per month, plus its ratable share of taxes, maintenance and other operating expenses. Base rent is subject to a 3.0% annual increase over the 10-year lease term. In addition, the Beacon Street Lease provides an extension option for one additional five-year term at then-market rates and includes a tenant improvement allowance of $10.0 million. The Company paid first month’s rent of $0.3 million upon execution of the Beacon Street Lease agreement and delivered a letter of credit of $2.0 million, which are classified in prepaid expenses and other current assets and other assets on the condensed consolidated balance sheet, respectively. Such amounts are refundable if the landlord does not deliver the premises under the Beacon Street Lease within a certain period of time. No further rent or operating expenses are owed until the Company takes occupancy at the contractual commencement date, which is currently anticipated to be in August 2021. The Beacon Street Lease requires the landlord to perform a scope of work to build-out the base building prior to the construction of the Company’s premises. The Company concluded the accounting commencement date will occur when the landlord completes the build-out of the base building and control passes to the Company, which the Company currently anticipates occurring in June 2021. The Company will assess the classification of the Beacon Street Lease at the accounting commencement date, measure the right-of-use asset and lease liability and begin recording leasehold improvements. The Company will concurrently assess the impact this has on the Arsenal Street right-of-use asset and lease liability. At the accounting commencement date, the prepaid rent will be reclassified as an increase in the right-of-use asset which will be reduced by the tenant improvement allowance. During the three months ended March 31, 2021, the Company paid a deposit of $2.6 million which represents the estimated cost of leasehold improvements in excess of the tenant improvement allowance that will be contributed towards leasehold improvements that will be constructed by the landlord on the Company’s behalf. The deposit is classified in other assets on the condensed consolidated balance sheets. In May 2021, the Company modified the Arsenal Street Lease to reduce the rentable square feet by approximately 50%. Pursuant to the modification, annual base rent and the Company’s share of operating expenses were reduced proportionate with the reduction in rentable square feet. There was no modification to the lease term for the remaining space, which remains subject to expiration thirty days following the lease commencement date of the Beacon Street Lease.

Accrued Expenses and Other Curr

Accrued Expenses and Other Current Liabilities	3 Months Ended
	Mar. 31, 2021
Payables And Accruals [Abstract]
Accrued Expenses and Other Current Liabilities	Note 8—Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities consisted of the following (in thousands): March 31, December 31, 2021 2020 Employee compensation $ 3,430 $ 6,834 Professional and consulting services 899 1,008 Research and development related accruals 17,035 18,290 Other current liabilities 851 972 $ 22,215 $ 27,104

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2021
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	Note 9—Commitments and Contingencies Guarantees and Indemnification Obligations The Company enters into standard indemnification agreements in the ordinary course of business. Pursuant to these agreements, the Company indemnifies and agrees to reimburse the indemnified party for losses and costs incurred by the indemnified party, generally the Company’s customers, in connection with any patent, copyright, trade secret or other intellectual property or personal right infringement claim by any third party with respect to the Company’s technology. The term of these indemnification agreements is generally perpetual after execution of the agreement. The maximum potential amount of future payments the Company could be required to make under these indemnification agreements is unlimited. Based on historical experience and information known as of March 31, 2021 and December 31, 2020, the Company had not incurred any costs for the above guarantees and indemnities.

Restructuring Charges

Restructuring Charges	3 Months Ended
	Mar. 31, 2021
Restructuring And Related Activities [Abstract]
Restructuring Charges	Note 10—Restructuring Charges In January 2019, the Company undertook an organization realignment to reduce the Company’s cost base and simplify its business goals to focus on a wholly owned pipeline. To achieve this cost reduction, the Company reduced its headcount by approximately 40%. The total restructuring charges incurred of $5.4 million were comprised of termination benefits including expenses for severance, health benefits and outplacement services. T The following table summarizes the restructuring activity incurred during the three months ended March 31, 2020 (in thousands): Accrued Restructuring Costs Balance at December 31, 2019 $ 325 Restructuring costs incurred 83 Termination benefits paid (240 ) Balance at March 31, 2020 $ 168

Redeemable Convertible and Conv

Redeemable Convertible and Convertible Preferred Stock	3 Months Ended
	Mar. 31, 2021
Temporary Equity [Abstract]
Redeemable Convertible and Convertible Preferred Stock	Note 11—Redeemable Convertible and Convertible Preferred Stock Immediately prior to the closing of the IPO, the Company had an aggregate of 86,062,799 shares of redeemable convertible and convertible preferred stock issued and outstanding which automatically converted into 20,349,223 shares of common stock. Subsequent to the closing of the IPO, no shares of preferred stock were issued or outstanding. As of March 31, 2020, the Company’s preferred stock consisted of the following (in thousands, except share data): Preferred Stock Authorized Preferred Stock Issued And Outstanding Carrying Value Liquidation Preference Common Stock Issuable Upon Conversion Series A 2,304,815 2,304,815 $ 4,656 $ 4,801 768,195 Series B-1 14,921,676 14,921,676 20,907 18,942 3,488,407 Series B-2 8,790,249 8,790,249 12,272 10,626 2,054,993 Series B-3 299,999 — — — — Series C 6,452,619 6,452,619 385 — 1,508,503 Series D 53,593,440 53,593,440 102,232 102,232 12,529,125 86,362,798 86,062,799 $ 140,452 $ 136,601 20,349,223 Upon the closing of the IPO, the Company filed the Second Amended Certificate of Incorporation to authorize 10,000,000 shares of preferred stock which were designated as undesignated preferred stock. As of March 31, 2021, no shares of preferred stock were issued or outstanding.

Stockholder's Equity

Stockholder's Equity	3 Months Ended
	Mar. 31, 2021
Stockholders Equity Note [Abstract]
Stockholders' Equity	Note 12—Stockholders’ Equity Common Stock Reserved for Future Issuances As of March 31, 2021, the Company had reserved for future issuance the following number of shares of common stock: Stock Reserved For exercise of stock options under the 2019 Stock Incentive Plan 3,929,379 For exercise of stock options under the 2020 Stock Option and Incentive Plan 1,927,047 For restricted stock units granted under the 2020 Stock Option and Incentive Plan 630,160 For future issuance under the 2020 Stock Option and Incentive Plan 2,889,988 For future issuance under the 2020 Employee Stock Purchase Plan 840,032 10,216,606

Equity-Based Compensation

Equity-Based Compensation	3 Months Ended
	Mar. 31, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Equity-Based Compensation	Note 13—Equity-Based Compensation 2020 Stock Option and Incentive Plan The Company grants stock-based awards under the 2020 Stock Option and Incentive Plan (“2020 Plan”). All shares of common stock underlying any awards that are forfeited, cancelled, expired, repurchased, or otherwise terminated under the 2020 and 2019 Plans are added back to the shares of common stock available for issuance under the 2020 Plan, while all unvested shares under the 2012 Plan that are forfeited, cancelled or are otherwise terminated that are reserved under the 2012 Plan are automatically retired. The Company also has stock options and restricted common stock outstanding under the 2019 Stock Incentive Plan (“2019 Plan”) and 2012 Equity Incentive Plan, as Amended and Restated, (“2012 Plan”) respectively, but is no longer granting awards under such plans. On January 1, 2021, the number of shares of common stock available for issuance under the 2020 Plan increased by 1,892,009 shares as a result of the automatic increase provision of the 2020 Plan. As of March 31, 2021, there were 2,889,988 shares available for future issuance under the 2020 Plan. Equity-Based Compensation Expense Equity-based compensation expense was as follows (in thousands): Three Months Ended March 31, 2021 2020 Research and development $ 1,455 $ 369 General and administrative 2,393 841 $ 3,848 $ 1,210 Enterprise junior stock $ — $ 231 Restricted common stock 100 — Restricted stock units 1,050 — Stock options 2,698 979 $ 3,848 $ 1,210 Stock Options The following table summarizes the Company’s stock option activity under the 2019 and 2020 Plans: Number of Shares Weighted Average Exercise Price Per share Weighted Average Remaining Contractual Term Aggregate Intrinsic Value (in years) (in thousands) Outstanding as of December 31, 2020 4,941,537 $ 8.62 9.1 $ 130,802 Granted 1,020,795 38.18 — — Exercised (68,389 ) 5.12 — — Forfeited (37,517 ) 5.23 — — Outstanding as of March 31, 2021 5,856,426 $ 13.83 9.1 $ 95,441 Exercisable as of March 31, 2021 1,307,293 $ 5.22 8.7 $ 29,803 Vested and expected to vest as of March 31, 2021 5,856,426 $ 13.83 9.1 $ 95,441 The weighted-average grant-date fair value per share of stock options granted during the three months ended March 31, 2021 and 2020 was $25.68 and $3.54, respectively. The aggregate intrinsic value of stock options exercised during the three months ended March 31, 2021 was $2.3 million. As of March 31, 2021, there was approximately $44.7 million of unrecognized equity-based compensation expense related to stock options that is expected to be recognized over a weighted-average period of approximately 3.0 years. Stock Options Valuation The following assumptions were used in determining the fair value of stock options, presented on a weighted average basis: Three Months Ended March 31, 2021 Three Months Ended March 31, 2020 Risk-free interest rate 0.94 % 1.50 % Expected term (in years) 6.1 6.0 Expected volatility 78.0 % 73.9 % Expected dividend yield 0.0 % 0.0 % Fair value per share of common stock $ 38.18 $ 5.43 Restricted Stock Units The following table summarizes the Company’s restricted stock unit activity under the 2020 Plan: NUMBER OF SHARES WEIGHTED AVERAGE GRANT DATE FAIR VALUE Unvested as of December 31, 2020 42,100 $ 42.26 Granted 588,060 $ 38.24 Unvested as of March 31, 2021 630,160 $ 38.50 No restricted stock units were granted during the three months ended March 31, 2020. Restricted Common Stock The following table summarizes the Company’s restricted common stock activity under the 2012 Plan: NUMBER OF SHARES WEIGHTED AVERAGE GRANT DATE FAIR VALUE Issued and unvested as of December 31, 2020 51,546 $ 7.44 Vested (11,501 ) $ 10.34 Forfeited (2,079 ) $ 14.88 Issued and unvested as of March 31, 2021 37,966 $ 6.12 The aggregate fair value of restricted common stock that vested during the three months ended March 31, 2021 was $0.1 million. As of March 31, 2021, there was approximately $0.2 million of unrecognized equity-based compensation expense related to the restricted common stock that is expected to be recognized over a weighted-average period of approximately 1.4 years. 2020 Employee Stock Purchase Plan The 2020 Employee Stock Purchase Plan (“ESPP”) became effective June 2020. As of , no shares have been issued under the ESPP and 840,032 shares remain available for issuance

Net Income (Loss) per Share

Net Income (Loss) per Share	3 Months Ended
	Mar. 31, 2021
Earnings Per Share [Abstract]
Net Income (Loss) per Share	Note 14—Net (Loss) Income per Share The following is a reconciliation of weighted-average common stock outstanding used in calculating basic net income per share to weighted-average common stock outstanding used in calculating diluted net income per share: Three Months Ended March 31, 2020 Weighted-average common stock outstanding, basic 2,548,079 Add: Effect of dilutive securities Series B-3 Preferred Warrants 3,961 Series A Preferred Stock 768,195 Series B-1 Preferred Stock 3,488,407 Series B-2 Preferred Stock 2,054,993 Series D Preferred Stock 12,529,125 Weighted-average common stock outstanding, diluted 21,392,760 The following table sets forth the outstanding shares of common stock equivalents, presented based on amounts outstanding at each period end, which were excluded from the calculation of diluted net (loss) income per share for the periods indicated because including them would have had an anti-dilutive effect: Three Months Ended March 31, 2021 2020 Series C Preferred Stock — 1,508,503 Enterprise junior stock (1) — 792,878 Stock options 5,856,426 3,890,596 Restricted common stock 37,966 — Restricted stock units 630,160 — (1) For purposes of determining the conversion ratio for the enterprise junior stock, the Company utilized the fair value per share of common stock of $5.48, which was based on a valuation performed as of March 15, 2020.

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2021
Income Tax Disclosure [Abstract]
Income Taxes	Note 15—Income Taxes Income taxes for the three months ended March 31, 2021 and 2020 have been calculated based on an estimated annual effective tax rate and certain discrete items. For the three months ended March 31, 2021 and 2020, the Company recorded an insignificant income tax expense and an income tax benefit $19.5 million, respectively. The Company’s income tax expense for the three months ended March 31, 2021 was related to state tax expense generated against investment income. The income tax benefit for the three months ended March 31, 2020 was related to refunds arising from the Coronavirus Aid, Relief and Economic Security Act (the “CARES Act”). On March 27, 2020, the CARES Act was enacted in response to the COVID-19 pandemic. Among other things, the CARES Act permits corporate taxpayers to carryback net operating losses (“NOLs”) originating in 2018 through 2020 to each of the five preceding tax years. Further, the CARES Act removed the 80% taxable income limitation on utilization of those NOLs allowing corporate taxpayers to fully utilize NOL carryforwards to offset taxable income in 2018, 2019 or 2020. Such changes resulted in the generation of refunds of previously paid income taxes for which some refunds have been received in 2020 and some refunds are expected to be received over the next twelve months. The Company has filed refund claims related to its 2018 and 2019 tax years and anticipates filing a refund claim related to its 2020 tax year to carryback NOLs to its 2015, 2016, 2017 and 2018 tax years for federal tax purposes which will result in anticipated refunds of $29.7 million, of which $19.5 million was recognized through March 31, 2020.

Collaboration Agreements

Collaboration Agreements	3 Months Ended
	Mar. 31, 2021
Collaboration And License Agreements Disclosure [Abstract]
Collaboration Agreements	Note 16—Collaboration Agreements In November 2010, the Company entered into an arrangement with a partner to deliver a compound library. Included in the arrangement were certain options to exclusive licenses for a defined number of library compounds. The Company determined the options represented material rights as they were exercisable for no additional consideration over the ten-year contract term. As of December 31, 2019, the Company had $1.2 million of deferred revenue related to the options. Pursuant to the Hit Discovery divestiture, the contract was assigned to and assumed by Valo Health and therefore the Company’s obligation relative to the options were released and assumed by Valo Health (see Note 17). Summary of Contract Assets and Liabilities The following table presents changes in the Company’s balances of contract liabilities (in thousands): Beginning of Period Additions Deductions End of Period Three months ended March 31, 2020 Deferred revenue $ 1,239 $ — $ 1,239 $ — Deferred revenue, noncurrent $ — $ — $ — $ — During the three months ended March 31, 2021 and 2020, the Company recognized no revenue. The Company had no contract asset balances as of and for the months ended March 31, 2021 and 2020.

Hit Discovery Divestiture

Hit Discovery Divestiture	3 Months Ended
	Mar. 31, 2021
Discontinued Operations And Disposal Groups [Abstract]
Hit Discovery Divestiture	Note 17—Hit Discovery Divestiture On March 16, 2020, the Company and Valo Health, Inc. (“Valo Health”, previously disclosed as “Integral Health, Inc.” and “NewCo”) executed an Agreement to divest select hit discovery capabilities (“Hit Discovery”, previously disclosed as “Early Discovery”). Valo Health purchased certain assets, including specified intellectual property, contracts and equipment used to conduct early stage hit identification and hit to lead discovery activities related to the identification, screening, and validation of compounds in early stage drug discovery from the Company. Additionally, certain of the Company’s employees terminated their employment with the Company and became employees of Valo Health. In exchange, the Company was entitled to receive: $17.5 million in cash, of which $2.5 million was paid at closing, and $15.0 million was payable in installments through June 1, 2021 (the “Installment Receivable”); $0.5 million of reimbursements for expenses prepaid by the Company, the benefit of which was transferred to Valo Health; and equity consideration equal to $10.0 million of equity in Valo Health’s next financing round or, if Valo Health’s next equity financing did not occur prior to the one-year anniversary of the closing of the Agreement, a number of shares of preferred stock issued in Valo Health’s previous round of equity financing prior to this Agreement equal to $10.0 million divided by the price per share paid by investors in that previous equity financing (the “Equity Consideration”). Further, if Valo Health closed a financing that met certain minimum thresholds prior to June 1, 2021, Valo Health would pay the Company the balance of the unpaid Installment Receivable. The Company is also eligible to receive low single digit future royalties on the aggregate net sales of any products that bind to a target in certain identified target classes, on a product-by-product and country-by-country basis during the periods of time commencing at the time of the first commercial sale of such product in such country, until the later of (i) the expiration of certain related patents and (ii) ten years after such first commercial sale (“Contingent Royalty Income”). The Company concluded that substantially all of the fair value of the gross assets sold was not concentrated in a single identifiable asset or group of similar identifiable assets based on the value of the identifiable tangible and intangible assets sold and the employees transferred as part of the transaction. The Company concluded that the asset group transferred to Valo Health constituted a business as the Company transferred inputs and processes that are capable of producing outputs. Further, the Company concluded it no longer had a controlling interest in the divested business subsequent to the transaction. The Company recognized a gain representing the difference between the fair value of the consideration received and the carrying amount of the net assets sold. The Company concluded the Equity Consideration was not a derivative instrument pursuant to ASC 815, Derivatives and Hedging, Equity Securities The fair value of the Installment Receivable was initially calculated as the present value of the then future cash payments to be received from Valo Health using a discount rate of 19.0% which factored in the risks associated with an The fair value of the total consideration received, as of the transaction date, used in calculating the gain on Hit Discovery divestiture is summarized as follows (in thousands): Fair Value Cash consideration: Cash due at closing $ 2,961 Installment Receivable 12,593 Non-cash consideration: Equity Consideration $ 10,000 Total fair value of consideration $ 25,554 The carrying value of the assets and liabilities included in the sale to Valo Health were as follows (in thousands): Carrying Amount Assets: Prepaid expenses and other current assets $ 1,117 Property and equipment, net 2,398 Other assets 125 $ 3,640 Liabilities: Accounts payable $ 159 Deferred revenue 1,239 $ 1,398 Net assets sold $ 2,242 The Company recognized a gain on Hit Discovery divestiture of $23.3 million which is presented as a separate component of other income on the Company’s condensed consolidated statement of operations and comprehensive (loss) income for the three months ended March 31, 2020. For the three months ended March 31, 2020, the Company recorded interest income of approximately $0.1 million related to the accretion of the Installment Receivable. Upon the execution of the Agreement, the Company accelerated the vesting of 23,317 stock options, 18,818 of which were held by employees who terminated employment with the Company as part of the transaction, in accordance with the respective award agreements. In addition, the Company modified 19,981 stock options to increase the exercise period from 90 days to one year from the date of termination for certain employees terminated in relation to the transaction. The incremental compensation expense associated with the modification was deemed immaterial. Separately, the Company recognized $0.5 million of research and development expense in the condensed consolidated statement of operations and comprehensive (loss) income for the three months ended March 31, 2020 related to a cash bonus payable as a result of the transaction. During the fourth quarter of 2020, Valo Health closed on their equity financing round. In connection with the closing, the Company received preferred shares in Valo Health in an amount equal to $10.0 million and the remaining balance of the Installment Receivable. The Company concluded the fair value of the equity interest received in Valo Health was equal to $10.0 million and continues to record the equity interest in other assets on the Company’s consolidated balance sheet as of March 31, 2021. No gain or loss was recorded by the Company in connection with the closing of Valo Health’s equity financing round as the carrying value of the Equity Consideration immediately prior to the closing was equal to the fair value of the equity interest that was received in Valo Health as part of the equity financing. As the Company does not have a significant influence on the operating and financial policies of Valo Health, the Company accounted for the equity interest received in Valo Health by applying the measurement alternative under ASC 321. As of March 31, 2021 and December 31, 2020, no impairments, nor any upward or downward adjustments have been recognized on the equity interest in Valo Health as a result of the application of the measurement alternative.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Liquidity	Liquidity The Company is focused on the development and commercialization of novel therapeutics to transform the lives of patients with rare hematologic diseases and cancers. The Company is building a pipeline of therapeutics with a focus on these areas and has devoted substantially all of its resources to the research and development of its drug development efforts, comprised of research and development, manufacturing, conducting clinical trials, protecting its intellectual property and general and administrative functions relating to these operations. The future success of the Company is dependent on its ability to develop its product candidates and ultimately upon its ability to attain sustained profitable operations through commercialization of products. The Company is subject to risks common to companies in the biotechnology industry, including but not limited to, the need for additional capital, risks of failure of preclinical studies and clinical trials, the need to obtain marketing approval and reimbursement for any drug product candidate that it may identify and develop, the need to successfully commercialize and gain market acceptance of its product candidates, dependence on key personnel, protection of proprietary technology, compliance with government regulations, development of technological innovations by competitors, reliance on third-party manufacturers and the ability to transition from pilot-scale production to large-scale manufacturing of products. The Company has determined that its cash, cash equivalents and marketable securities of $603.7 million as of March 31, 2021 will be sufficient to fund its operations for at least one year from the date these condensed consolidated financial statements are issued. To date, the Company has primarily financed its operations through license and collaboration agreements, the sale of preferred shares and preferred stock to outside investors and the completion of the IPO and follow-on public offering. The Company has experienced significant negative cash flows from operations during the three months ended March 31, 2021. The Company does not expect to experience any significant positive cash flows from its existing collaboration agreements and does not expect to have any product revenue in the near term. The Company expects to incur substantial operating losses and negative cash flows from operations for the foreseeable future as it continues to invest significantly in research and development of its programs. Management’s belief with respect to its ability to fund operations is based on estimates that are subject to risks and uncertainties. If actual results are different from management’s estimates, the Company may need to seek additional funding sooner than would otherwise be expected. There can be no assurance that the Company will be able to obtain additional funding on acceptable terms, if at all.
Basis of Presentation and Consolidation	Basis of Presentation and Consolidation The condensed consolidated financial statements include the accounts of Forma Therapeutics Holdings, Inc. and its wholly owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation. The Company has prepared the accompanying condensed consolidated financial statements in conformity with accounting principles generally accepted in the United States of America (“GAAP”) and pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). Certain information and footnote disclosures generally included in financial statements in conformity with GAAP have been condensed or omitted in accordance with such rules and regulations. Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standard Updates (“ASU”) of the Financial Accounting Standards Board (“FASB”).
Unaudited Interim Condensed Consolidated Financial Statements	Unaudited Interim Condensed Consolidated Financial Statements The accompanying condensed consolidated balance sheet as of March 31, 2021, the condensed consolidated statements of operations and comprehensive (loss) income for the three months ended March 31, 2021 and 2020, the condensed consolidated statements of redeemable convertible and convertible preferred stock and stockholders’ equity (deficit) for the three months ended March 31, 2021 and 2020 and the condensed consolidated statements of cash flows for the three months ended March 31, 2021 and 2020 are unaudited. The financial data and other information contained in the notes thereto as of March 31, 2021 and for the three months ended March 31, 2021 and 2020 are also unaudited. The condensed consolidated balance sheet data as of December 31, 2020 was derived from the Company’s audited consolidated financial statements included in the Annual Report on Form 10-K for the fiscal year ended December 31, 2020. With the exception of the adoption of ASU No. 2016-02, Leases (Topic 842)
Cash, Cash Equivalents and Restricted Cash	Cash, Cash Equivalents and Restricted Cash The Company considers all short-term, highly liquid investments with original maturities of 90 days or less at acquisition date to be cash equivalents. The carrying amounts of the Company’s cash equivalents approximate their fair value due to their short-term nature. Amounts in restricted cash consist of letters of credit to secure the Company’s facilities, including its new lease for office and laboratory space entered into in September 2020 (see Note 7). Restricted cash is included in other assets on the condensed consolidated balance sheets. The following table reconciles cash, cash equivalents and restricted cash as of March 31, 2021 and 2020 to the condensed consolidated statements of cash flows (in thousands): March 31, 2021 2020 Cash and cash equivalents $ 97,834 $ 110,329 Restricted cash 2,470 495 Total cash, cash equivalents and restricted cash as shown in the condensed consolidated statements of cash flows $ 100,304 $ 110,824
Marketable Securities	Marketable Securities Marketable securities generally consist of U.S. Treasury securities, debt securities of U.S. government agencies and corporate entities and commercial paper. The objectives for holding investments are to invest the Company’s excess cash resources in investment vehicles that provide a better rate of return compared to an interest-bearing bank account with limited risk to the principal invested. Marketable securities with original maturities of greater than 90 days and remaining maturities of less than one year from the balance sheet date are classified as short-term marketable securities. Marketable securities with remaining maturities of greater than one year from the balance sheet date are classified as long-term marketable securities. All investments are classified as held-to-maturity marketable securities as the Company does not have intent to sell these securities and it is more likely than not the Company will not be required to sell such investments before recovery of their amortized cost basis. Held-to-maturity securities are stated at their amortized cost, adjusted for amortization of premiums and accretion of discounts to maturity. Such amortization and accretion is included in interest income in the condensed consolidated statements of operations and comprehensive (loss) income.
Comprehensive (Loss) Income	Comprehensive (Loss) Income Comprehensive (loss) income includes net (loss) income as well as other changes in stockholders’ equity that result from transactions and economic events other than those with the equity holders. There was no difference between net (loss) income and comprehensive (loss) income presented in the accompanying condensed consolidated financial statements for the three months ended March 31, 2021 and 2020.
Equity-Based Compensation	Equity-Based Compensation The Company accounts for equity awards, including grants of enterprise incentive shares, enterprise junior stock, stock options, restricted stock units and restricted common stock, in accordance with ASC 718, Compensation – Stock Compensation Subsequent to the IPO, the fair value of the Company’s common stock underlying its equity awards is based on the quoted market price of the Company’s common stock on the grant date. The Company estimates the fair value of stock options using the Black-Scholes option pricing model, which uses as inputs the fair value of the Company’s common stock, and certain management estimates, including the expected stock price volatility, the expected term of the award, the risk-free rate, and expected dividends. Expected volatility is calculated based on reported volatility data for a representative group of publicly traded companies for which historical information is available. The Company selects companies with comparable characteristics with historical share price information that approximates the expected term of the equity-based awards. The Company computes the historical volatility data using the daily closing prices for the selected companies’ shares during the equivalent period that approximates the calculated expected term of the stock options. The Company will continue to apply this method until a sufficient amount of historical information regarding the volatility of its stock price becomes available. The risk-free interest rate is based on the U.S. Treasury yield curve in effect at the time of grant commensurate with the expected term assumption. The Company uses the simplified method, under which the expected term is presumed to be the midpoint between the vesting date and the end of the contractual term. The Company utilizes this method due to lack of historical exercise data. The expected dividend yield is assumed to be zero as the Company has no current plans to pay any dividends on common stock. Prior to the IPO, for awards granted in the first quarter of 2020, the Company used a probability-weighted expected returns method (“PWERM”) with four scenarios to value the common stock underlying the awards: an IPO, a delayed IPO, a sale of the Company and a remain private scenario. In the IPO and sale scenarios, the Company estimated an equity value based on the guideline public company method under a market approach. The guideline public companies consisted of biopharmaceutical companies with recently completed initial public offerings. For the remain private scenario, the Company back-solved to the price of a recently issued preferred security. The Company converted its estimated future value in each scenario to present value using a risk-adjusted discount rate. The relative probability of each scenario was determined based on an assessment of then-current market conditions. Where appropriate, the Company applied a discount for lack of marketability to the value indicated for the common stock. The valuation methodology used to value the common stock prior to the IPO included estimates and assumptions that required the Company’s judgment. Significant changes to the key assumptions used in the valuations could have resulted in different fair values of the Company’s common stock at each valuation date. For awards with service-based vesting conditions, the Company recognizes equity-based compensation expense on a straight-line basis over the vesting period. For awards subject to performance conditions, the Company recognizes equity-based compensation expense using an accelerated recognition method over the remaining service period when the Company determines the achievement of the performance condition is probable. The Company classifies equity-based compensation expense in its condensed consolidated statements of operations and comprehensive (loss) income consistent with the classification of the award recipient’s compensation expense.
Leases	Leases Effective January 1, 2021, the Company adopted Topic 842 using the required modified retrospective approach and utilizing the effective date as its date of initial application. As a result, prior periods are presented in accordance with the previous guidance in ASC 840, Leases The Company evaluates whether an arrangement is or contains a lease at the inception date. If determined to be or contain a lease, the Company determines the classification of the lease at the commencement date, which represents the date at which the lessor makes the underlying asset available for use by the Company. When determining the expected accounting lease term, the Company includes the noncancellable lease term, together with periods covered by (i) an option to extend the lease if the Company is reasonably certain to exercise such option, (ii) an option to terminate the lease if the Company is reasonably certain not to exercise such option and (iii) an option to extend or not terminate the lease where the exercise of such option is controlled by the lessor. The Company has elected the short-term lease exemption, which allows the Company to not recognize lease liabilities and right-of-use assets arising from lease arrangements with original lease terms of twelve months or less. The Company elected the practical expedient to not separate lease and non-lease components for its real estate leases. Right-of-use assets represent the Company’s right to use an underlying asset over the lease term and lease liabilities represent the Company’s obligation to make lease payments under the arrangement. The Company measures its lease liabilities as the present value of the lease payments, discounted using an incremental borrowing rate, as interest rates implicit in lease arrangements are generally not readily determinable. The Company measures its right-of-use assets as the present value of its lease payments at the commencement date, adjusted for prepaid rent payments and tenant incentives. The incremental borrowing rate represents the interest rate at which the Company could borrow an amount equal to the lease payments on a fully collateralized basis, over a similar term, in a similar economic environment. The Company recognizes rent expense for operating leases on a straight-line basis. The Company recognizes variable lease expenses as incurred. The Company remeasures right-of-use assets and lease liabilities when a lease is modified, and the modification is not accounted for as a separate contract. A modification is accounted for as a separate contract if the modification grants the Company an additional right of use not included in the original lease arrangement and the increase in lease payments is commensurate with the additional right of use. The Company assesses its right-of-use assets for impairment in a manner consistent with its assessment for long-lived assets held and used in operations.
Recently Adopted Accounting Pronouncements	Recently Adopted Accounting Pronouncements In February 2016, the FASB Topic 842 which supersedes the existing guidance for lease accounting. The FASB has issued several updates to the standard which: (i) clarify how to apply certain aspects of the new standard; (ii) provide an additional transition method for adoption of the new standard; (iii) provide a practical expedient for certain lessor accounting; and (iv) amend certain narrow aspects of the guidance. Topic 842 requires the identification and classification of arrangements that are or contain a lease. In general, for lease arrangements exceeding a twelve-month term, these arrangements must be recognized as assets and liabilities on the balance sheet of the lessee. Under Topic 842, a right-of-use asset and lease obligation will be recorded for all leases, whether operating or financing, while the income statement will reflect lease expense for operating leases and amortization/interest expense for financing leases. The balance sheet amount recorded for existing leases at the date of adoption of Topic 842 is calculated using the applicable incremental borrowing rate at the date of adoption. Topic 842 is effective for the Company on January 1, 2022, with early adoption permitted. The Company elected to early adopt the new standard and used the modified retrospective approach effective January 1, 2021 as the initial date of application. The Company elected the available package of practical expedients which allowed the Company to not reassess previous accounting conclusions around whether arrangements are or contain leases, the classification of leases, and the treatment of initial direct costs. As a result of the adoption of Topic 842, the Company recorded (i) an operating lease liability of $8.9 million and (ii) an operating lease right-of-use asset of $7.5 million, net of the unamortized balance of deferred rent liability and tenant improvement allowances as of the transition date. There was no impact to the Company’s results of operations and cash flows from operations. A summary of the impact of the adoption is as follows (in thousands): December 31, 2020 Impact of Adoption January 1, 2021 Operating lease right-of-use asset $ — $ 7,478 $ 7,478 Accrued expenses and other current liabilities 27,104 (399 ) 26,705 Operating lease liability, current — 3,025 3,025 Deferred rent, noncurrent 1,027 (1,027 ) — Operating lease liability, noncurrent — 5,879 5,879

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Summary of Reconciles Cash, Cash equivalents and Restricted Cash	The following table reconciles cash, cash equivalents and restricted cash as of March 31, 2021 and 2020 to the condensed consolidated statements of cash flows (in thousands): March 31, 2021 2020 Cash and cash equivalents $ 97,834 $ 110,329 Restricted cash 2,470 495 Total cash, cash equivalents and restricted cash as shown in the condensed consolidated statements of cash flows $ 100,304 $ 110,824
Summary of the impact of the adoption	A summary of the impact of the adoption is as follows (in thousands): December 31, 2020 Impact of Adoption January 1, 2021 Operating lease right-of-use asset $ — $ 7,478 $ 7,478 Accrued expenses and other current liabilities 27,104 (399 ) 26,705 Operating lease liability, current — 3,025 3,025 Deferred rent, noncurrent 1,027 (1,027 ) — Operating lease liability, noncurrent — 5,879 5,879

Fair Value of Financial Asset_2

Fair Value of Financial Assets and Liabilities (Tables)	3 Months Ended
	Mar. 31, 2021
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Schedule of Assets Measured at Fair Value on a Recurring Basis	The following tables present information about the Company’s assets that are measured or disclosed at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values (in thousands): Fair Value Measurements at the Reporting Date Using March 31, 2021 Quoted Prices In Active Markets Using Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets—Cash equivalents Repurchase agreement $ 12,000 $ — $ 12,000 $ — Money market funds 62,993 62,993 — — Commercial paper 19,999 — 19,999 — Assets—Short-term marketable securities U.S. Government agency securities 61,708 — 61,708 — U.S. Treasury securities 21,209 21,209 — — Commercial paper 330,550 — 330,550 — Corporate debt securities 39,468 — 39,468 — Assets—Long-term marketable securities U.S. Government agency securities 29,981 — 29,981 — U.S. Treasury securities 23,003 23,003 — — Total $ 600,911 $ 107,205 $ 493,706 $ — Fair Value Measurements at the Reporting Date Using December 31, 2020 Quoted Prices In Active Markets Using Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets—Cash equivalents Repurchase agreement $ 12,000 $ — $ 12,000 $ — Commercial paper 22,493 — 22,493 — Money market funds 227,987 227,987 — — Assets—Short-term marketable securities U.S. Government agency securities 55,469 — 55,469 — U.S. Treasury securities 38,294 38,294 — — Commercial paper 237,735 — 237,735 — Corporate debt securities 18,873 — 18,873 — Assets—Long-term marketable securities U.S. Government agency securities 7,049 — 7,049 — Corporate debt securities 5,492 — 5,492 — Total $ 625,392 $ 266,281 $ 359,111 $ —
Fair Value Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Summary of Changes in Fair Value of the Level 3 Warrant Liability	The following table provides a summary of changes in fair value of the Level 3 warrant liability (in thousands): Warrant Liability Balance at December 31, 2019 $ 364 Change in fair value (20 ) Balance at March 31, 2020 $ 344
Series B-3 Convertible Preferred Stock
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Schedule of Assumptions Used to Determine the Fair Value of Warrants to Purchase Series B-3 Convertible Preferred Stock	The following assumptions were used to determine the fair value of the warrants to purchase Series B-3 Preferred Stock: March 31, 2020 Risk-free interest rate 0.4 % Expected term (in years) 5.3 Expected volatility 72.6 % Expected dividend yield 0.0 % Fair value per share of underlying Series B-3 Preferred Stock $ 1.46

Marketable Securities (Tables)

Marketable Securities (Tables)	3 Months Ended
	Mar. 31, 2021
Investments Debt And Equity Securities [Abstract]
Held-to-maturity Securities	The Company’s investments by type consisted of the following (in thousands): March 31, 2021 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Assets U.S. Government agency securities $ 91,687 $ 17 $ (15 ) $ 91,689 U.S. Treasury securities 44,201 11 — 44,212 Commercial paper 330,520 41 (11 ) 330,550 Corporate debt securities 39,482 — (14 ) 39,468 Total $ 505,890 $ 69 $ (40 ) $ 505,919 December 31, 2020 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Assets U.S. Government agency securities $ 62,508 $ 10 $ — $ 62,518 U.S. Treasury securities 38,287 7 — 38,294 Commercial paper 237,733 18 (16 ) 237,735 Corporate debt securities 24,371 3 (9 ) 24,365 Total $ 362,899 $ 38 $ (25 ) $ 362,912

Prepaid Expenses and Other Cu_2

Prepaid Expenses and Other Current Assets (Tables)	3 Months Ended
	Mar. 31, 2021
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
Schedule of Prepaid Expenses and Other Current Assets	Prepaid expenses and other current assets consisted of the following (in thousands): March 31, December 31, 2021 2020 Prepaid expenses $ 6,065 $ 4,793 Other non-trade receivables 2,009 1,327 $ 8,074 $ 6,120

Property and Equipment, Net (Ta

Property and Equipment, Net (Tables)	3 Months Ended
	Mar. 31, 2021
Property Plant And Equipment [Abstract]
Schedule of Property and Equipment, Net	Property and equipment, net consisted of the following (in thousands): March 31, December 31, 2021 2020 Computer and office equipment $ 2,294 $ 2,253 Software 2,473 2,473 Lab equipment 4,602 4,560 Furniture and fixtures 377 377 Leasehold improvements 3,402 3,402 13,148 13,065 Less: Accumulated depreciation (11,728 ) (11,545 ) $ 1,420 $ 1,520

Leases (Table)

Leases (Table)	3 Months Ended
	Mar. 31, 2021
Leases [Abstract]
Component of Operating Lease Expenses	The components of operating lease expense were as follows (in thousands): Three Months Ended March 31, 2021 Operating lease cost $ 468 Variable lease cost 226 $ 694
Summary of Supplemental Cash Flow Information Related to Operating Leases	Supplemental cash flow information related to operating leases was as follows (in thousands): Three Months Ended March 31, 2021 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows related to operating leases $ 564
Schedule of Future Minimum Payments Under Noncancelable Operating Leases	Future minimum lease payments under noncancellable leases as of March 31, 2021 were as follows (in thousands): Operating Leases 2021 (excluding the three months ended March 31, 2021) $ 2,334 2022 3,177 2023 3,246 2024 197 2025 — Total lease payments 8,954 Present value adjustment (699 ) Present value of operating lease liabilities $ 8,255

Accrued Expenses and Other Cu_2

Accrued Expenses and Other Current Liabilities (Tables)	3 Months Ended
	Mar. 31, 2021
Payables And Accruals [Abstract]
Schedule of Accrued Expenses and Other Current Liabilities	Accrued expenses and other current liabilities consisted of the following (in thousands): March 31, December 31, 2021 2020 Employee compensation $ 3,430 $ 6,834 Professional and consulting services 899 1,008 Research and development related accruals 17,035 18,290 Other current liabilities 851 972 $ 22,215 $ 27,104

Restructuring Charges (Tables)

Restructuring Charges (Tables)	3 Months Ended
	Mar. 31, 2021
Restructuring And Related Activities [Abstract]
Restructuring and Related Costs	The following table summarizes the restructuring activity incurred during the three months ended March 31, 2020 (in thousands): Accrued Restructuring Costs Balance at December 31, 2019 $ 325 Restructuring costs incurred 83 Termination benefits paid (240 ) Balance at March 31, 2020 $ 168

Redeemable Convertible and Co_2

Redeemable Convertible and Convertible Preferred Stock (Tables)	3 Months Ended
	Mar. 31, 2021
Temporary Equity [Abstract]
Schedule of Convertible Preferred Stock	As of March 31, 2020, the Company’s preferred stock consisted of the following (in thousands, except share data): Preferred Stock Authorized Preferred Stock Issued And Outstanding Carrying Value Liquidation Preference Common Stock Issuable Upon Conversion Series A 2,304,815 2,304,815 $ 4,656 $ 4,801 768,195 Series B-1 14,921,676 14,921,676 20,907 18,942 3,488,407 Series B-2 8,790,249 8,790,249 12,272 10,626 2,054,993 Series B-3 299,999 — — — — Series C 6,452,619 6,452,619 385 — 1,508,503 Series D 53,593,440 53,593,440 102,232 102,232 12,529,125 86,362,798 86,062,799 $ 140,452 $ 136,601 20,349,223

Stockholder's Equity (Tables)

Stockholder's Equity (Tables)	3 Months Ended
	Mar. 31, 2021
Stockholders Equity Note [Abstract]
Schedule of Reserved Common Stock for Warrants to Purchase Common Stock and Future Issuance	As of March 31, 2021, the Company had reserved for future issuance the following number of shares of common stock: Stock Reserved For exercise of stock options under the 2019 Stock Incentive Plan 3,929,379 For exercise of stock options under the 2020 Stock Option and Incentive Plan 1,927,047 For restricted stock units granted under the 2020 Stock Option and Incentive Plan 630,160 For future issuance under the 2020 Stock Option and Incentive Plan 2,889,988 For future issuance under the 2020 Employee Stock Purchase Plan 840,032 10,216,606

Equity-Based Compensation (Tabl

Equity-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Summary of Stock-Based Compensation Expense	Equity-based compensation expense was as follows (in thousands): Three Months Ended March 31, 2021 2020 Research and development $ 1,455 $ 369 General and administrative 2,393 841 $ 3,848 $ 1,210 Enterprise junior stock $ — $ 231 Restricted common stock 100 — Restricted stock units 1,050 — Stock options 2,698 979 $ 3,848 $ 1,210
Summary of Stock Option Activity	Stock Options The following table summarizes the Company’s stock option activity under the 2019 and 2020 Plans: Number of Shares Weighted Average Exercise Price Per share Weighted Average Remaining Contractual Term Aggregate Intrinsic Value (in years) (in thousands) Outstanding as of December 31, 2020 4,941,537 $ 8.62 9.1 $ 130,802 Granted 1,020,795 38.18 — — Exercised (68,389 ) 5.12 — — Forfeited (37,517 ) 5.23 — — Outstanding as of March 31, 2021 5,856,426 $ 13.83 9.1 $ 95,441 Exercisable as of March 31, 2021 1,307,293 $ 5.22 8.7 $ 29,803 Vested and expected to vest as of March 31, 2021 5,856,426 $ 13.83 9.1 $ 95,441
Schedule of Assumptions to Estimate Fair Value of Stock Options, Presented on a Weighted Average Basis	The following assumptions were used in determining the fair value of stock options, presented on a weighted average basis: Three Months Ended March 31, 2021 Three Months Ended March 31, 2020 Risk-free interest rate 0.94 % 1.50 % Expected term (in years) 6.1 6.0 Expected volatility 78.0 % 73.9 % Expected dividend yield 0.0 % 0.0 % Fair value per share of common stock $ 38.18 $ 5.43
Restricted Stock Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Summary of Stock Option Activity	The following table summarizes the Company’s restricted stock unit activity under the 2020 Plan: NUMBER OF SHARES WEIGHTED AVERAGE GRANT DATE FAIR VALUE Unvested as of December 31, 2020 42,100 $ 42.26 Granted 588,060 $ 38.24 Unvested as of March 31, 2021 630,160 $ 38.50
Restricted Common Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Summary of Stock Option Activity	The following table summarizes the Company’s restricted common stock activity under the 2012 Plan: NUMBER OF SHARES WEIGHTED AVERAGE GRANT DATE FAIR VALUE Issued and unvested as of December 31, 2020 51,546 $ 7.44 Vested (11,501 ) $ 10.34 Forfeited (2,079 ) $ 14.88 Issued and unvested as of March 31, 2021 37,966 $ 6.12

Net Income (Loss) per Share (Ta

Net Income (Loss) per Share (Tables) - Common Class 1 [Member]	3 Months Ended
	Mar. 31, 2021
Schedule of Weighted-Average Common Shares Outstanding used in Calculating Basic and Diluted Net Income per Share	The following is a reconciliation of weighted-average common stock outstanding used in calculating basic net income per share to weighted-average common stock outstanding used in calculating diluted net income per share: Three Months Ended March 31, 2020 Weighted-average common stock outstanding, basic 2,548,079 Add: Effect of dilutive securities Series B-3 Preferred Warrants 3,961 Series A Preferred Stock 768,195 Series B-1 Preferred Stock 3,488,407 Series B-2 Preferred Stock 2,054,993 Series D Preferred Stock 12,529,125 Weighted-average common stock outstanding, diluted 21,392,760
Summary of Potentially Dilutive Securities Excluded from Calculation of Diluted Net Income (Loss) per Share	The following table sets forth the outstanding shares of common stock equivalents, presented based on amounts outstanding at each period end, which were excluded from the calculation of diluted net (loss) income per share for the periods indicated because including them would have had an anti-dilutive effect: Three Months Ended March 31, 2021 2020 Series C Preferred Stock — 1,508,503 Enterprise junior stock (1) — 792,878 Stock options 5,856,426 3,890,596 Restricted common stock 37,966 — Restricted stock units 630,160 —

Collaboration Agreements (Table

Collaboration Agreements (Tables)	3 Months Ended
	Mar. 31, 2021
Collaboration And License Agreements Disclosure [Abstract]
Summary of Contract Assets and Liabilities	The following table presents changes in the Company’s balances of contract liabilities (in thousands): Beginning of Period Additions Deductions End of Period Three months ended March 31, 2020 Deferred revenue $ 1,239 $ — $ 1,239 $ — Deferred revenue, noncurrent $ — $ — $ — $ —

Hit Discovery Divestiture (Tabl

Hit Discovery Divestiture (Tables)	3 Months Ended
	Mar. 31, 2021
Discontinued Operations And Disposal Groups [Abstract]
Schedule of Fair Value of Total Consideration to be Received Used in Calculating the Gain on Hit Discovery Divestiture	The fair value of the total consideration received, as of the transaction date, used in calculating the gain on Hit Discovery divestiture is summarized as follows (in thousands): Fair Value Cash consideration: Cash due at closing $ 2,961 Installment Receivable 12,593 Non-cash consideration: Equity Consideration $ 10,000 Total fair value of consideration $ 25,554
Carrying Value of Assets and Liabilities included in Sale to Valo Health	The carrying value of the assets and liabilities included in the sale to Valo Health were as follows (in thousands): Carrying Amount Assets: Prepaid expenses and other current assets $ 1,117 Property and equipment, net 2,398 Other assets 125 $ 3,640 Liabilities: Accounts payable $ 159 Deferred revenue 1,239 $ 1,398 Net assets sold $ 2,242

Organization and Nature of Bu_2

Organization and Nature of Business - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	Dec. 15, 2020	Jun. 23, 2020	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019
Class Of Stock [Line Items]
Entity incorporation, date of incorporation			Dec. 31, 2011
Issuance of common stock from initial public offering, net of issuance costs, Shares	795,000
Shares issued and sold, public offering price | $ / shares	$ 45.25
Net proceeds from initial public offering	$ 258.6
Preferred stock shares outstanding		0	0	0
Authorized capital stock		160,000,000
Common stock shares authorized			150,000,000	150,000,000
Preferred stock shares authorized		10,000,000	10,000,000	10,000,000
Preferred stock par value		$ 0.001	$ 0.001	$ 0.001
Gross proceeds from follow on public offering	$ 275.8
Cash, cash equivalents and marketable securities			$ 603.7
Enterprise Junior Stock [Member]
Class Of Stock [Line Items]
Temporary equity shares outstanding					2,635,430	2,597,091
Temporary equity shares issued		103,007
Common Stock
Class Of Stock [Line Items]
Issuance of common stock from initial public offering, net of issuance costs, Shares	6,095,000	2,082,352
Gross proceeds from initial public offering		$ 319.3
Net proceeds from initial public offering		$ 293.3
Temporary equity shares outstanding		20,349,223
Common Stock | Enterprise Junior Stock [Member]
Class Of Stock [Line Items]
Temporary equity shares issued		2,124,845
Common Stock | Voting Common Stock [Member]
Class Of Stock [Line Items]
Common stock shares authorized		147,494,175
Common Stock | Non Voting Common Stock [Member]
Class Of Stock [Line Items]
Common stock shares authorized		2,505,825
Warrant
Class Of Stock [Line Items]
Number of warrants issued to purchase common stock | shares		70,133
Warrants exercise price, per share | $ / shares		$ 5.13
Warrant | Series B3 Preferred Stock [Member]
Class Of Stock [Line Items]
Number of warrants issued to purchase common stock | shares		299,999
Warrants exercise price, per share | $ / shares		$ 1.20
IPO [Member] | Common Stock
Class Of Stock [Line Items]
Issuance of common stock from initial public offering, net of issuance costs, Shares		15,964,704
Shares issued and sold, public offering price | $ / shares		$ 20

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Additional Information (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2021USD ($)shares	Jan. 01, 2021USD ($)	Sep. 30, 2020USD ($)
Summary Of Significant Accounting Policies [Line Items]
Short-term, highly liquid investments with original maturities	90 days or less
Operating Lease, Liability	$ 8,255	$ 8,900
Operating lease right-of-use asset		$ 7,478	$ 6,927
Measurement Input, Expected Dividend Rate [Member]
Summary Of Significant Accounting Policies [Line Items]
Expected dividend yield | shares	0

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Summary of Reconciles Cash, Cash equivalents and Restricted Cash (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Mar. 31, 2020	Dec. 31, 2019
Accounting Policies [Abstract]
Cash and cash equivalents	$ 97,834	$ 282,689	$ 97,834	$ 110,329
Restricted cash	2,470			495
Total cash, cash equivalents and restricted cash as shown in the condensed consolidated statements of cash flows	$ 100,304	$ 285,159		$ 110,824	$ 173,796

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Summary of the impact of the adoption (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Jan. 01, 2021	Dec. 31, 2020	Sep. 30, 2020
Summary Of Significant Accounting Policies [Line Items]
Operating lease right-of-use asset		$ 7,478		$ 6,927
Accrued expenses and other current liabilities		26,705	$ 27,104	22,215
Operating lease liability		3,025		3,041
Deferred rent, noncurrent			$ 1,027
Operating lease liability, noncurrent		$ 5,879		$ 5,214
Impact of Adoption [Member]
Summary Of Significant Accounting Policies [Line Items]
Operating lease right-of-use asset	$ 7,478
Accrued expenses and other current liabilities	(399)
Operating lease liability	3,025
Deferred rent, noncurrent	(1,027)
Operating lease liability, noncurrent	$ 5,879

Fair Value of Financial Asset_3

Fair Value of Financial Assets and Liabilities - Schedule of Assets Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Assets, Fair Value Disclosure
Assets	$ 600,911	$ 625,392
Repurchase agreements
Assets, Fair Value Disclosure
Assets	12,000	12,000
Money market funds
Assets, Fair Value Disclosure
Assets	62,993	227,987
Commercial Paper
Assets, Fair Value Disclosure
Assets	19,999	22,493
Commercial Paper | Short-Term Marketable Securities
Assets, Fair Value Disclosure
Assets	330,550	237,735
Corporate Debt Securities | Short-Term Marketable Securities
Assets, Fair Value Disclosure
Assets	39,468	18,873
Corporate Debt Securities | Long-Term Marketable Securities
Assets, Fair Value Disclosure
Assets		5,492
US Government Corporations and Agencies Securities | Short-Term Marketable Securities
Assets, Fair Value Disclosure
Assets	61,708	55,469
US Government Corporations and Agencies Securities | Long-Term Marketable Securities
Assets, Fair Value Disclosure
Assets	29,981	7,049
US Treasury Securities | Short-Term Marketable Securities
Assets, Fair Value Disclosure
Assets	21,209	38,294
US Treasury Securities | Long-Term Marketable Securities
Assets, Fair Value Disclosure
Assets	23,003
Quoted Prices in Active Markets Using Identical Assets (Level 1)
Assets, Fair Value Disclosure
Assets	107,205	266,281
Quoted Prices in Active Markets Using Identical Assets (Level 1) | Money market funds
Assets, Fair Value Disclosure
Assets	62,993	227,987
Quoted Prices in Active Markets Using Identical Assets (Level 1) | US Treasury Securities | Short-Term Marketable Securities
Assets, Fair Value Disclosure
Assets	21,209	38,294
Quoted Prices in Active Markets Using Identical Assets (Level 1) | US Treasury Securities | Long-Term Marketable Securities
Assets, Fair Value Disclosure
Assets	23,003
Significant Other Observable Inputs (Level 2)
Assets, Fair Value Disclosure
Assets	493,706	359,111
Significant Other Observable Inputs (Level 2) | Repurchase agreements
Assets, Fair Value Disclosure
Assets	12,000	12,000
Significant Other Observable Inputs (Level 2) | Commercial Paper
Assets, Fair Value Disclosure
Assets	19,999	22,493
Significant Other Observable Inputs (Level 2) | Commercial Paper | Short-Term Marketable Securities
Assets, Fair Value Disclosure
Assets	330,550	237,735
Significant Other Observable Inputs (Level 2) | Corporate Debt Securities | Short-Term Marketable Securities
Assets, Fair Value Disclosure
Assets	39,468	18,873
Significant Other Observable Inputs (Level 2) | Corporate Debt Securities | Long-Term Marketable Securities
Assets, Fair Value Disclosure
Assets		5,492
Significant Other Observable Inputs (Level 2) | US Government Corporations and Agencies Securities | Short-Term Marketable Securities
Assets, Fair Value Disclosure
Assets	61,708	55,469
Significant Other Observable Inputs (Level 2) | US Government Corporations and Agencies Securities | Long-Term Marketable Securities
Assets, Fair Value Disclosure
Assets	$ 29,981	$ 7,049

Fair Value of Financial Asset_4

Fair Value of Financial Assets and Liabilities - Additional Information (Details) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2021USD ($)shares	Mar. 31, 2020USD ($)Warrant$ / sharesshares
Warrant
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Warrant outstanding	0
Series B-3 Convertible Preferred Stock | Warrant
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Number of warrants to purchase | Warrant		3
Convertible preferred stock warrant purchased		299,999
Exercise price per share | $ / shares		$ 1.20
Fair Value Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Transfers into out of Level 3 | $	$ 0	$ 0

Fair Value of Financial Asset_5

Fair Value of Financial Assets and Liabilities - Schedule of Assumptions Used to Determine the Fair Value of Warrants to Purchase Series B-3 Convertible Preferred Stock (Details)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020shares
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Fair value per share of underlying Series B-3 Preferred Stock		1.46
Series B-3 Convertible Preferred Stock | Risk-free interest rate
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Derivative liability, measurement input		0.4
Series B-3 Convertible Preferred Stock | Expected term (in years)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Expected term (in years)	5 years 3 months 19 days
Series B-3 Convertible Preferred Stock | Expected volatility
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Derivative liability, measurement input		72.6
Series B-3 Convertible Preferred Stock | Measurement Input, Expected Dividend Rate [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Derivative liability, measurement input		0

Fair Value of Financial Asset_6

Fair Value of Financial Assets and Liabilities - Summary of Changes in Fair Value of the Level 3 Warrant Liability (Details) - Fair Value Level 3 $ in Thousands	3 Months Ended
	Mar. 31, 2020USD ($)
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning Balance	$ 364
Change in fair value	(20)
Ending Balance	$ 344

Marketable Securities - Held-to

Marketable Securities - Held-to-maturity Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Schedule Of Investment Income Reported Amounts By Category [Line Items]
Amortized Cost	$ 505,890	$ 362,899
Gross Unrealized Gains	69	38
Gross Unrealized Losses	(40)	(25)
Estimated Fair Value	505,919	362,912
US Treasury Securities
Schedule Of Investment Income Reported Amounts By Category [Line Items]
Amortized Cost	44,201	38,287
Gross Unrealized Gains	11	7
Estimated Fair Value	44,212	38,294
Commercial Paper
Schedule Of Investment Income Reported Amounts By Category [Line Items]
Amortized Cost	330,520	237,733
Gross Unrealized Gains	41	18
Gross Unrealized Losses	(11)	(16)
Estimated Fair Value	330,550	237,735
US Government Debt Securities
Schedule Of Investment Income Reported Amounts By Category [Line Items]
Amortized Cost	91,687	62,508
Gross Unrealized Gains	17	10
Gross Unrealized Losses	(15)
Estimated Fair Value	91,689	62,518
Corporate Debt Securities
Schedule Of Investment Income Reported Amounts By Category [Line Items]
Amortized Cost	39,482	24,371
Gross Unrealized Gains		3
Gross Unrealized Losses	(14)	(9)
Estimated Fair Value	$ 39,468	$ 24,365

Marketable Securities - Additio

Marketable Securities - Additional Information (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Investments Debt And Equity Securities [Abstract]
Unrealized loss position with an aggregate fair value	$ 191.4	$ 93.7

Prepaid Expenses and Other Cu_3

Prepaid Expenses and Other Current Assets - Schedule of Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
Prepaid expenses	$ 6,065	$ 4,793
Other non-trade receivables	2,009	1,327
Prepaid and other current assets	$ 8,074	$ 6,120	$ 8,074

Property and Equipment, Net - S

Property and Equipment, Net - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 13,148	$ 13,065
Less: Accumulated depreciation	(11,728)	(11,545)
Property and equipment, net	1,420	1,520	$ 1,420
Computer and office equipment [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	2,294	2,253
Software [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	2,473	2,473
Lab equipment [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	4,602	4,560
Furniture and fixtures [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	377	377
Leasehold improvements [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 3,402	$ 3,402

Property and Equipment, Net - A

Property and Equipment, Net - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Property Plant And Equipment [Abstract]
Depreciation and amortization	$ 183	$ 543

Leases - Additional Information

Leases - Additional Information (Details) - USD ($) $ in Thousands	Jan. 01, 2018	May 31, 2021	Mar. 31, 2021	Sep. 30, 2020	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Jan. 01, 2021
Lessee Lease Description [Line Items]
Tenant Improvement Allowance			$ 500
Other Assets			$ 500
Lease Expiration Date			Jan. 31, 2024
Option to extend lease term	The lease terms provide for one five-year extension term with base rent calculated on a discounted then-market rate.		The Arsenal Street Lease terms provide for one five-year extension term with base rent calculated on the then-market rate
Aggregate tenant improvements of the premises	$ 1,000		$ 2,600
Lease term expiration	2023-12
Aggregate tenant improvements of the premises, unused	$ 100
Future minimum rental payments due			8,954
Operating Leases, Rent Expense			200
Sublease Income			$ 200
Weighted average remaining lease term			2 years 9 months 18 days
Weighted average incremental borrowing rate percent			6.00%
Operating Lease, Liability			$ 8,255					$ 8,900
Lease Agreements
Lessee Lease Description [Line Items]
Option to extend lease term				MA (the “Beacon Street Lease”). The Beacon Street Lease, which includes office and laboratory space, is subject to base rent of $0.3 million per month, plus its ratable share of taxes, maintenance and other operating expenses. Base rent is subject to a 3.0% annual increase over the 10-year lease term. In addition, the Beacon Street Lease provides an extension option for one additional five-year term at then-market rates and includes a tenant improvement allowance of $10.0 million.
Aggregate tenant improvements of the premises				$ 10,000
Lease term expiration				2021-08
Lease agreement date				2020-09
Lessee operating lease description				No further rent or operating expenses are owed until the Company takes occupancy at the contractual commencement date, which is currently anticipated to be in August 2021
Lessee operating lease discount rate				3.00%
Operating Lease, Liability				$ 300
Letters of credit outstanding amount				$ 2,000
Forecast
Lessee Lease Description [Line Items]
Future minimum rental payments due					$ 800	$ 800	$ 600
Percentage of reduction in leased area		50.00%
Lease expiration period		30 days

Leases - Components of Lease Co

Leases - Components of Lease Costs (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2021USD ($)
Leases [Abstract]
Operating lease cost	$ 468
Variable lease cost	226
Lease cost	$ 694

Leases - Summary of Supplementa

Leases - Summary of Supplemental Cash Flow Information Related to Operating Lease (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2021USD ($)
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows related to operating leases	$ 564

Leases - Schedule of Future Min

Leases - Schedule of Future Minimum Payments Under Noncancelable Operating Leases (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Jan. 01, 2021
Leases [Abstract]
2021 (excluding the three months ended March 31, 2021)	$ 2,334
2022	3,177
2023	3,246
2024	197
Total lease payments	8,954
Present value adjustment	(699)
Operating Lease, Liability	$ 8,255	$ 8,900

Accrued Expenses and Other Cu_3

Accrued Expenses and Other Current Liabilities - Schedule of Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Payables And Accruals [Abstract]
Employee compensation	$ 3,430	$ 6,834
Professional and consulting services	899	1,008
Research and development related accruals	17,035	18,290
Other current liabilities	851	972
Accrued Expenses And Other Liabilities Current Net	$ 22,215	$ 27,104

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Commitments And Contingencies Disclosure [Abstract]
Cost for guarantees and indemnities	$ 0	$ 0

Restructuring Charges - Additio

Restructuring Charges - Additional Information (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended
	Jan. 31, 2019	Mar. 31, 2021	Mar. 31, 2020
Restructuring And Related Activities [Abstract]
Percentage of reduction in head count for cost reduction	40.00%
Restructuring charges	$ 5,400		$ 83
Restructuring Charges, Description		The Company did not incur any charges in the first quarter of 2021 and the remaining balance of its restructuring accrual was paid in June 2020.

Restructuring Charges - Summary

Restructuring Charges - Summary of the Restructuring Activity (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended
	Jan. 31, 2019	Mar. 31, 2020
Restructuring And Related Activities [Abstract]
Beginning Balance		$ 325
Restructuring costs incurred	$ 5,400	83
Termination benefits paid		(240)
Ending Balance		$ 168

Redeemable Convertible and Co_3

Redeemable Convertible and Convertible Preferred Stock - Additional Information (Details) - shares	Mar. 31, 2021	Dec. 31, 2020	Jun. 23, 2020
Preferred stock shares issued	0	0
Preferred stock shares outstanding	0	0	0
Conversion of redeemable convertible and convertible preferred stock into common stock			20,349,223
Preferred stock shares authorized	10,000,000	10,000,000	10,000,000
Series B-3 Convertible Preferred Stock
Preferred stock shares issued			86,062,799
Preferred stock shares outstanding			86,062,799
Redeemable Convertible Preferred Stock
Preferred stock shares issued			86,062,799
Preferred stock shares outstanding			86,062,799

Redeemable Convertible and Co_4

Redeemable Convertible and Convertible Preferred Stock - Schedule of Convertible Preferred Stock (Details) $ in Thousands	Mar. 31, 2021USD ($)shares
Temporary equity shares authorized | shares	86,362,798
Preferred Stock Issued And Outstanding | shares	86,062,799
Total redeemable convertible preferred stock	$ 140,452
Temporary equity liquidation preference	136,601
Common Stock Issuable Upon Conversion	$ 20,349,223
Series A Preferred Stock
Temporary equity shares authorized | shares	2,304,815
Preferred Stock Issued And Outstanding | shares	2,304,815
Total redeemable convertible preferred stock	$ 4,656
Temporary equity liquidation preference	4,801
Common Stock Issuable Upon Conversion	$ 768,195
Series B1 Preferred Stock
Temporary equity shares authorized | shares	14,921,676
Preferred Stock Issued And Outstanding | shares	14,921,676
Total redeemable convertible preferred stock	$ 20,907
Temporary equity liquidation preference	18,942
Common Stock Issuable Upon Conversion	$ 3,488,407
Series B2 Preferred Stock
Temporary equity shares authorized | shares	8,790,249
Preferred Stock Issued And Outstanding | shares	8,790,249
Total redeemable convertible preferred stock	$ 12,272
Temporary equity liquidation preference	10,626
Common Stock Issuable Upon Conversion	$ 2,054,993
Series B3 Preferred Stock [Member]
Temporary equity shares authorized | shares	299,999
Series C Preferred Stock
Temporary equity shares authorized | shares	6,452,619
Preferred Stock Issued And Outstanding | shares	6,452,619
Total redeemable convertible preferred stock	$ 385
Common Stock Issuable Upon Conversion	$ 1,508,503
Series D Preferred Stock
Temporary equity shares authorized | shares	53,593,440
Preferred Stock Issued And Outstanding | shares	53,593,440
Total redeemable convertible preferred stock	$ 102,232
Temporary equity liquidation preference	102,232
Common Stock Issuable Upon Conversion	$ 12,529,125

Stockholder's Equity - Schedule

Stockholder's Equity - Schedule of Reserved Common Stock for Warrants to Purchase Common Stock and Future Issuance (Details)	Mar. 31, 2021shares
Schedule Of Capitalization [Line Items]
Common Stock, Capital Stock Reserved for Future Issuance	10,216,606
2019 Stock Incentive Plan Exercised [Member]
Schedule Of Capitalization [Line Items]
Common Stock, Capital Stock Reserved for Future Issuance	3,929,379
2020 Stock Option and Incentive Plan Exercised [Member]
Schedule Of Capitalization [Line Items]
Common Stock, Capital Stock Reserved for Future Issuance	1,927,047
2020 Stock Option and Incentive Plan Restricted [Member]
Schedule Of Capitalization [Line Items]
Common Stock, Capital Stock Reserved for Future Issuance	630,160
2020 Stock Option and Incentive Plan Future Issuance [Member]
Schedule Of Capitalization [Line Items]
Common Stock, Capital Stock Reserved for Future Issuance	2,889,988
2020 Employee Stock Option Purchase Plan Future Issuance [Member]
Schedule Of Capitalization [Line Items]
Common Stock, Capital Stock Reserved for Future Issuance	840,032

Equity-Based Compensation - Add

Equity-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares outstanding	47,328,575		47,248,685
Aggregate Intrinsic Value, Exercisable	$ 29,803
Equity based compensation expense	$ 3,848	$ 1,210
Weighted Average Remaining Contractual Term, Outstanding	9 years 1 month 6 days		9 years 1 month 6 days
Number of Shares, Granted	1,020,795
Restricted Stock Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted average fair value of options granted (in dollars per share)	$ 38.24
Equity based compensation expense	$ 23,100
Weighted Average Remaining Contractual Term, Outstanding	3 years 2 months 12 days
Number of Shares, Granted	588,060	0
Restricted Common Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted average fair value of options granted (in dollars per share)	$ 0.1
Equity based compensation expense	$ 200
Weighted Average Remaining Contractual Term, Outstanding	1 year 4 months 24 days
Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted average fair value of options granted (in dollars per share)	$ 25.68	$ 3.54
Aggregate Intrinsic Value, Exercisable	$ 2,300
Equity based compensation expense	$ 44,700
Weighted Average Remaining Contractual Term, Outstanding	3 years
2020 Stock Option And Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares outstanding	2,889,988
Annual increase common stock issuance	1,892,009
2020 Employee stock purchase plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares outstanding	840,032
Annual increase common stock issuance	472,487
Shares issued under ESPP	0

Equity-Based Compensation - Sum

Equity-Based Compensation - Summary of 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]
Equity based compensation expense	$ 3,848	$ 1,210
Research and Development
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Equity based compensation expense	1,455	369
General and Administrative
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Equity based compensation expense	2,393	841
Enterprise Junior Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Equity based compensation expense		231
Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Equity based compensation expense	2,698	$ 979
Restricted Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Equity based compensation expense	100
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Equity based compensation expense	$ 1,050

Equity-Based Compensation - S_2

Equity-Based Compensation - Summary of Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Number of Shares, Outstanding beginning balance	4,941,537
Number of Shares, Granted	1,020,795
Number of Shares, Exercised	(68,389)
Number of Shares, Forfeited	(37,517)
Number of Shares, Outstanding ending balance	5,856,426	4,941,537
Number of Shares, Exercisable	1,307,293
Number of Shares, Vested and expected to vest	5,856,426
Weighted Average Exercise Price Per share, Outstanding beginning balance	$ 8.62
Weighted Average Exercise Price Per share, Granted	38.18
Weighted Average Exercise Price Per share, Exercised	5.12
Weighted Average Exercise Price Per share, Forfeited	5.23
Weighted Average Exercise Price Per share, Outstanding ending balance	13.83	$ 8.62
Weighted Average Exercise Price Per share, Exercisable	5.22
Weighted Average Exercise Price Per share, Vested and expected to vest	$ 13.83
Weighted Average Remaining Contractual Term, Outstanding	9 years 1 month 6 days	9 years 1 month 6 days
Weighted Average Remaining Contractual Term, Exercisable	8 years 8 months 12 days
Weighted Average Remaining Contractual Term, Vested and expected to vest	9 years 1 month 6 days
Aggregate Intrinsic Value, Outstanding	$ 130,802
Aggregate Intrinsic Value, Outstanding	95,441	$ 130,802
Aggregate Intrinsic Value, Exercisable	29,803
Aggregate Intrinsic Value, Vested and expected to vest	$ 95,441

Equity-Based Compensation - Sch

Equity-Based Compensation - Schedule of Assumptions to Estimate Fair Value of Stock Options, Presented on a Weighted Average Basis (Details) - $ / shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Risk-free interest rate	0.94%	1.50%
Expected term (in years)	6 years 1 month 6 days	6 years
Expected volatility	78.00%	73.90%
Expected dividend yield	0.00%	0.00%
Fair value per share of common stock	$ 38.18	$ 5.43

Equity-Based Compensation - S_3

Equity-Based Compensation - Summary of Restricted Stock Unit Activity (Details) - $ / shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares, Granted	1,020,795
Restricted Stock Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares, Beginning balance	42,100
Number of Shares, Granted	588,060	0
Number of Shares, Ending balance	630,160
Weighted Average Grant Date Fair Value, Beginning period	$ 42.26
Weighted average fair value of options granted (in dollars per share)	38.24
Weighted Average Grant Date Fair Value, Ending period	$ 38.50

Equity-Based Compensation - S_4

Equity-Based Compensation - Summary of Restricted Common Stock Activity (Details) - Restricted Common Stock [Member]	3 Months Ended
	Mar. 31, 2021$ / sharesshares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares, Beginning balance | shares	51,546
Number of Shares, Vested | shares	(11,501)
Number of Shares, Forfeited | shares	(2,079)
Number of Shares, Ending balance | shares	37,966
Weighted Average Grant Date Fair Value, Beginning period | $ / shares	$ 7.44
Weighted Average Grant Date Fair Value, Vested | $ / shares	10.34
Weighted Average Grant Date Fair Value, Forfeited | $ / shares	14.88
Weighted Average Grant Date Fair Value, Ending period | $ / shares	$ 6.12

Net Income (Loss) per Share - S

Net Income (Loss) per Share - Schedule of Weighted-Average Common Shares Outstanding used in Calculating Basic and Diluted Net Income per Share (Details) - shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Basic	47,295,013	2,548,079
Add: Effect of dilutive securities
Diluted	47,295,013	21,392,760
Series A Preferred Stock [Member]
Add: Effect of dilutive securities
Diluted	768,195
Series B-1 Preferred Stock [Member]
Add: Effect of dilutive securities
Diluted	3,488,407
Series B-2 Preferred Stock [Member]
Add: Effect of dilutive securities
Diluted	2,054,993
Series D Preferred Stock
Add: Effect of dilutive securities
Diluted	12,529,125
Common Class 1 [Member]
Basic	2,548,079
Add: Effect of dilutive securities
Diluted	21,392,760
Series B-3 Preferred Warrants
Add: Effect of dilutive securities
Diluted	3,961

Net Income (Loss) per Share -_2

Net Income (Loss) per Share - Summary of Potentially Dilutive Securities Excluded from Calculation of Diluted Net Income (Loss) per Share (Details) - shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Series C Preferred Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from calculation of diluted net loss per share		1,508,503
Enterprise Junior Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from calculation of diluted net loss per share		792,878
Stock Option [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from calculation of diluted net loss per share	5,856,426	3,890,596
Restricted Stock Units [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from calculation of diluted net loss per share	630,160
Restricted Common Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from calculation of diluted net loss per share	37,966

Net Loss per Share - Summary of

Net Loss per Share - Summary of Potentially Dilutive Securities Excluded from Calculation of Diluted Net Loss per Share (Details) (Parenthetical) - $ / shares	Mar. 31, 2021	Dec. 31, 2020	Mar. 15, 2020
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Common stock par value	$ 0.001	$ 0.001
Enterprise Junior Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Common stock par value			$ 5.48

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	Mar. 27, 2020	Mar. 31, 2021	Mar. 31, 2020
Income Tax Disclosure [Line Items]
Income tax expense (benefit)		$ 8	$ (19,485)
Federal tax anticipated refunds		$ 29,700	$ 19,500
Cares Act
Income Tax Disclosure [Line Items]
Percentage of removal on taxable income on non operating losses	80.00%

Collaboration Agreements - Addi

Collaboration Agreements - Additional Information (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended
	Nov. 30, 2010	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2019
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue		$ 0	$ 0
Contract asset balances		$ 0	$ 0
Other Collaboration Agreements | Stock Option [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Contract term	10 years
Deferred revenue				$ 1,200

Collaboration Agreements - Summ

Collaboration Agreements - Summary of Contract Assets and Liabilities (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2021USD ($)
Collaboration And License Agreements Disclosure [Abstract]
Deferred revenue, Beginning of Period	$ 1,239
Deferred revenue, Deductions	$ 1,239

Hit Discovery Divestiture - Add

Hit Discovery Divestiture - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Jun. 01, 2021
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Net proceeds from Hit Discovery divestiture	$ 17,500
Installment receivable	12,593
Prepaid of reimbursement expense	500
Equity consideration	10,000
Research and development	26,343	$ 23,210
Impairment to equity consideration	$ 0
Fair Value Discount Rate
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Fair value discount rate	19.00%
Hit Discovery Divestiture [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Fair value of equity consideration	$ 10,000
Gain on hit discovery divestiture	23,300
Interest income	$ 100
Number of stock options vested	23,317
Number of stock options vested, held by terminated employees	18,818
Number of stock options, modified	19,981
Stock options, modification terms	the Company modified 19,981 stock options to increase the exercise period from 90 days to one year from the date of termination for certain employees terminated in relation to the transaction.
Research and development	$ 500
Valo Health [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Cash received	2,500
Valo Health [Member] | Hit Discovery Divestiture [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Gain on hit discovery divestiture	0
Preferred shares in Valo Health	10,000
Fair value of the equity interest received	$ 10,000
Valo Health [Member] | Subsquent Event
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Installment receivable			$ 15,000

Hit Discovery Divestiture - Sch

Hit Discovery Divestiture - Schedule of Fair Value of Total Consideration to be Received Used in Calculating the Gain on Hit Discovery Divestiture (Details) $ in Thousands	Mar. 31, 2021USD ($)
Fair Value Cash consideration:
Fair Value Cash due at closing	$ 2,961
Fair Value Installment Receivable	12,593
Fair Value Non-cash consideration:
Fair Value Equity Consideration	10,000
Total fair value of consideration	$ 25,554

Hit Discovery Divestiture - Car

Hit Discovery Divestiture - Carrying Value of Assets and Liabilities included in Sale to Valo Health (Details) $ in Thousands	Mar. 31, 2021USD ($)
Assets:
Prepaid expenses and other current assets	$ 1,117
Property and equipment, net	2,398
Other assets	125
Disposal Group, Including Discontinued Operation, Assets	3,640
Liabilities:
Accounts payable	159
Deferred revenue	1,239
Disposal Group, Including Discontinued Operation, Liabilities	1,398
Net assets sold	$ 2,242