Revolution Medicines (RVMD) 10-Q 10 May 21 2021 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2021	May 05, 2021
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Entity Registrant Name	Revolution Medicines, Inc.
Entity Central Index Key	0001628171
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		73,442,594
Entity Shell Company	false
Entity Small Business	false
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Title of 12(b) Security	Common Stock $0.0001 Par Value per Share
Trading Symbol	RVMD
Security Exchange Name	NASDAQ
Entity File Number	001-39219
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	47-2029180
Entity Address, Address Line One	700 Saginaw Drive
Entity Address, City or Town	Redwood City
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94063
City Area Code	650
Local Phone Number	481-6801
Document Quarterly Report	true
Document Transition Report	false

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 351,595	$ 104,268
Marketable securities	329,998	336,473
Accounts receivable	7,564	6,393
Prepaid expenses and other current assets	8,248	6,988
Total current assets	697,405	454,122
Property and equipment, net	10,879	8,902
Operating lease right-of-use asset	26,695	27,435
Intangible assets, net	60,678	60,945
Goodwill	14,608	14,608
Restricted cash	1,084	1,084
Other noncurrent assets	302	305
Total assets	811,651	567,401
Current liabilities:
Accounts payable	9,650	12,609
Accrued expenses and other current liabilities	20,445	18,784
Operating lease liability, current	3,700	3,672
Deferred revenue, current	9,964	12,111
Total current liabilities	43,759	47,176
Deferred revenue, noncurrent	8,135	8,481
Deferred tax liability	7,444	7,444
Operating lease liability, noncurrent	28,294	28,992
Other noncurrent liabilities	1,439	632
Total liabilities	89,071	92,725
Commitments and contingencies (Note 7)
Stockholders' equity (deficit):
Preferred stock, $0.0001 par value; 10,000,000 shares authorized at March 31, 2021 and December 31, 2020, respectively; zero shares issued and outstanding at March 31, 2021 and December 31, 2020, respectively
Common stock, $0.0001 par value; 300,000,000 shares authorized at March 31, 2021 and December 31, 2020, respectively; 73,435,109 and 66,599,748 shares issued and outstanding at March 31, 2021 and December 31, 2020, respectively	8	7
Additional paid-in capital	1,025,230	740,098
Accumulated other comprehensive income	63	116
Accumulated deficit	(302,721)	(265,545)
Total stockholders' equity (deficit)	722,580	474,676
Total liabilities, redeemable convertible preferred stock and stockholders' equity	$ 811,651	$ 567,401

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 or stated value per share	$ 0.0001	$ 0.0001
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 or stated value per share	$ 0.0001	$ 0.0001
Common stock, shares authorized	300,000,000	300,000,000
Common stock, shares, issued	73,435,109	66,599,748
Common stock, shares, outstanding	73,435,109	66,599,748

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Revenue:
Total revenue	$ 10,131	$ 11,546
Operating expenses:
Research and development	40,858	27,457
General and administrative	6,670	5,171
Total operating expenses	47,528	32,628
Loss from operations	(37,397)	(21,082)
Other income (expense), net:
Interest income	233	909
Interest expense	(12)	(21)
Total other income (expense), net	221	888
Loss before income taxes	(37,176)	(20,194)
Benefit from income taxes		675
Net loss	(37,176)	(19,519)
Redeemable convertible preferred stock dividends - undeclared and cumulative		(2,219)
Net loss attributable to common stockholders	$ (37,176)	$ (21,738)
Net loss per share attributable to common stockholders - basic and diluted	$ (0.53)	$ (0.74)
Weighted-average common shares used to compute net loss per share, basic and diluted	70,420,076	29,297,698
Collaboration Revenue
Revenue:
Total revenue	$ 10,131	$ 11,546

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (37,176)	$ (19,519)
Other comprehensive income/(loss)
Unrealized gain (loss) on investments, net	(53)	(38)
Total comprehensive loss	$ (37,229)	$ (19,557)

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF REDEEMABLE CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY (DEFICIT) (Unaudited) - USD ($) $ in Thousands	Total	Follow-on Offering	Initial Public Offering	Common Stock	Common StockFollow-on Offering	Common StockInitial Public Offering	Additional Paid-In Capital	Additional Paid-In CapitalFollow-on Offering	Additional Paid-In CapitalInitial Public Offering	Accumulated Other Comprehensive Income	Accumulated Deficit	Redeemable Convertible Preferred Stock
Beginning balance at Dec. 31, 2019	$ (152,574)						$ 4,738			$ 74	$ (157,386)
Redeemable convertible preferred stock, beginning balance, shares at Dec. 31, 2019												39,600,423
Redeemable convertible preferred stock, beginning balance at Dec. 31, 2019												$ 305,109
Beginning balance, shares at Dec. 31, 2019				3,292,124
Conversion of redeemable convertible preferred stock into common stock	305,109			$ 4			305,105					$ (305,109)
Conversion of redeemable convertible preferred stock into common stock, shares				39,600,423								(39,600,423)
Issuance of common stock upon offering, net of offering costs			$ 250,697			$ 2			$ 250,695
Issuance of common stock upon offering, net of offering costs, shares						16,100,000
Issuance of common stock pursuant to stock option exercises	27						27
Issuance of common stock pursuant to stock option exercises, shares				11,097
Vesting of early exercised stock options	47						47
Stock-based compensation expense	1,567						1,567
Net unrealized loss on marketable securities	(38)									(38)
Net loss	(19,519)										(19,519)
Ending balance at Mar. 31, 2020	385,316			$ 6			562,179			36	(176,905)
Ending balance, shares at Mar. 31, 2020				59,003,644
Beginning balance at Dec. 31, 2020	$ 474,676			$ 7			740,098			116	(265,545)
Redeemable convertible preferred stock, beginning balance, shares at Dec. 31, 2020	0
Beginning balance, shares at Dec. 31, 2020				66,599,748
Issuance of common stock upon offering, net of offering costs		$ 281,145			$ 1			$ 281,144
Issuance of common stock upon offering, net of offering costs, shares					6,666,666
Issuance of common stock pursuant to stock option exercises	$ 555						555
Issuance of common stock pursuant to stock option exercises, shares				166,897
Issuance of common stock related to vesting of restricted stock units, shares				1,798
Vesting of early exercised stock options	46						46
Stock-based compensation expense	3,387						3,387
Net unrealized loss on marketable securities	(53)									(53)
Net loss	(37,176)										(37,176)
Ending balance at Mar. 31, 2021	$ 722,580			$ 8			$ 1,025,230			$ 63	$ (302,721)
Redeemable convertible preferred stock, ending balance, shares at Mar. 31, 2021	0
Ending balance, shares at Mar. 31, 2021				73,435,109

CONDENSED CONSOLIDATED STATEM_4

CONDENSED CONSOLIDATED STATEMENTS OF REDEEMABLE CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY (DEFICIT) (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Initial Public Offering
Stock issuance cost		$ 23,003
Follow-on Offering
Stock issuance cost	$ 18,855

CONDENSED CONSOLIDATED STATEM_5

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	$ (37,176)	$ (19,519)
Adjustments to reconcile net loss to net cash used in operating activities:
Amortization of intangible assets	267	267
Stock-based compensation expense	3,387	1,567
Depreciation and amortization	671	632
Net amortization (accretion) of premium (discount) on marketable securities	534	(105)
Amortization of operating lease right-of-use asset	740	645
Changes in operating assets and liabilities:
Accounts receivable	(1,171)	287
Prepaid expenses and other current assets	(1,257)	(3,202)
Accounts payable	(2,131)	(3,084)
Accrued expenses and other current liabilities	1,200	(963)
Deferred revenue	(2,493)	(3,033)
Deferred tax liability		(716)
Operating lease liability	(670)	(775)
Other noncurrent liabilities	853	(19)
Net cash used in operating activities	(37,246)	(28,018)
Cash flows from investing activities
Purchases of marketable securities	(114,038)	(100,038)
Maturities of marketable securities	119,926	40,925
Purchases of property and equipment	(3,579)	(603)
Net cash provided by (used in) investing activities	2,309	(59,716)
Cash flows from financing activities
Proceeds from issuance of common stock, net of issuance costs	281,709	253,717
Proceeds from issuance of common stock under equity incentive plans	555	27
Net cash provided by financing activities	282,264	253,744
Net increase in cash, cash equivalents and restricted cash	247,327	166,010
Cash, cash equivalents and restricted cash - beginning of period	105,352	16,873
Cash, cash equivalents and restricted cash - end of period	352,679	182,883
Reconciliation of cash, cash equivalents and restricted cash to consolidated balance sheets
Cash and cash equivalents	351,595	182,669
Restricted cash	1,084	214
Cash, cash equivalents and restricted cash - end of period	352,679	182,883
Supplemental disclosure of non-cash investing and financing activities
Vesting of early exercised options and restricted stock	46	47
Purchases of property and equipment in accounts payable and accrued expenses and other current liabilities	882	37
Unpaid offering costs	$ 564	$ 1,417

Organization

Organization	3 Months Ended
	Mar. 31, 2021
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Organization	1. Organization Revolution Medicines, Inc. (the Company) is a clinical-stage precision oncology company focused on developing targeted therapies to inhibit frontier targets in RAS-addicted cancers. The Company was founded in October 2014 and is headquartered in Redwood City, California. Liquidity The Company has incurred net operating losses in each year since inception. As of March 31, 2021, the Company had an accumulated deficit of $302.7 Public offerings In February 2020, the Company closed its initial public offering (IPO), and issued 16,100,000 shares of its common stock (including the exercise in full by the underwriters of their option to purchase an additional 2,100,000 shares of the Company’s common stock) at a price to the public of $17.00 per share for net proceeds of $250.7 after deducting underwriting discounts and commissions of $19.2 million and expenses of $3.8 million. In July 2020, the Company issued 6,900,000 shares of its common stock in an underwritten public offering (including the exercise in full by the underwriters of their option to purchase an additional 900,000 shares of the Company’s common stock) at a price of $26.00 per share for net proceeds of $167.8 million, after deducting underwriting discounts and commissions of $10.8 In February 2021, the Company issued 6,666,666 shares of its common stock in an underwritten public offering (including the exercise in full by the underwriters of their option to purchase an additional 869,565 shares of the Company’s common stock) at a price of $45.00 per share for net proceeds of $281.1 million, after deducting underwriting discounts and commissions of $18.0 million and expenses of $0.9 million.

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of significant accounting policies Basis of presentation The condensed consolidated financial statements have been prepared in conformity with generally accepted accounting principles in the United States (GAAP) and applicable rules of the Securities and Exchange Commission (SEC) regarding interim financial reporting Reverse stock split On February 7, 2020, the Company amended and restated its amended and restated certificate of incorporation to effect a 1-for-4.8661 reverse stock split of the Company’s common stock and redeemable convertible preferred stock. The par value and authorized shares of the common stock and redeemable convertible preferred stock were not adjusted as a result of the reverse stock split. All issued and outstanding common stock, options to purchase common stock and per share amounts contained in the financial statements have been retroactively adjusted to give effect to the reverse stock split for all periods presented. Use of estimates The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. On an ongoing basis, management evaluates its estimates, including those related to revenue recognition, clinical accruals, valuation of in-process research and development and developed technologies, income taxes, useful lives of property and equipment and intangible assets, impairment of goodwill, and stock-based compensation. The extent to which the COVID-19 pandemic may directly or indirectly impact the Company’s business, financial condition and results of operations is highly uncertain and subject to change. The Company considered the potential impact of the COVID-19 pandemic on its estimates and assumptions and there was not a material impact to the Company’s condensed consolidated financial statements as of and for the three months ended March 31, 2021. Actual results could materially differ from the Company’s estimates, and there may be changes to the estimates in future periods . Concentration of credit risk and other risks and uncertainties Financial instruments that potentially subject the Company to concentration of credit risk consist of cash, cash equivalents and marketable securities. The Company’s cash is held by two financial institutions in the United States, which management believes to be of high credit quality. The Company invests in money market funds, U.S. government debt securities, U.S. government agency bonds, commercial paper and corporate bonds. The Company has not experienced any losses on its deposits of cash and cash equivalents. The Company is subject to credit risk as its accounts receivable and collaboration revenue are entirely related to its collaboration agreement with Sanofi. See Note 8, “Sanofi collaboration agreement.” The Company’s clinical trial sites for its RMC-4630 and RMC-5552 clinical studies may be affected by the COVID-19 outbreak due to prioritization of hospital resources toward the COVID-19 outbreak, travel or quarantine restrictions imposed by governments, and the inability to access sites for initiation and patient monitoring and enrollment. As a result, patient screening, new patient enrollment, monitoring and data collection may be affected or delayed. The Company is aware that several clinical sites involved in its RMC-4630 clinical studies temporarily stopped or delayed enrolling new patients, with exemptions if appropriate, and it is possible that these or other clinical sites may be similarly affected in the future. These developments may delay the Company’s clinical trial timelines. Some of the Company’s third-party manufacturers which it uses for the supply of materials for product candidates or other materials necessary to manufacture product to conduct preclinical tests and clinical trials and contract research organizations may be impacted by Leases The Company determines if an arrangement is, or contains, a lease at inception and then classifies the lease as operating or financing based on the underlying terms and conditions of the contract. Leases with terms greater than one year are initially recognized on the balance sheet as right-of-use assets and lease liabilities based on the present value of lease payments over the expected lease term. The interest rate implicit in lease contracts is typically not readily determinable. As such, the Company utilizes the incremental borrowing rate, which is the rate incurred to borrow, on a collateralized basis, an amount equal to the lease payments over a similar term and in a similar economic environment of the applicable country or region. Variable lease payments are excluded from the right-of-use assets and operating lease liabilities and are recognized in the period in which the obligation for those payments is incurred. Recent accounting pronouncements From time to time, new accounting pronouncements are issued by the FASB, under its ASC or other standard setting bodies, and adopted by the Company as of the specified effective date, unless otherwise discussed below. Recently adopted accounting pronouncements In December 2019, the Financial Accounting Standards Board (FASB) issued ASU 2019-12, Income Taxes (Topic 740)-Simplifying the Accounting for Income Taxes Recent accounting pronouncements not yet adopted In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments Codification Improvements to Topic 326, Financial Instruments—Credit Losses Financial Instruments—Credit Losses (Topic 326): Targeted Transition Relief In August 2018, the FASB issued ASU No. 2018-15, Intangibles—Goodwill and Other-Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract In October 2020, the FASB issued ASU 2020-08, Codification Improvements to Subtopic 310-20, Receivables-Nonrefundable Fees and Other Costs In October 2020, FASB issued ASU 2020-10, Codification Improvements

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2021
Fair Value Disclosures [Abstract]
Fair Value Measurements	3. Fair value measurements The carrying amounts of the Company’s certain financial instruments, including cash equivalents, accounts payable and accrued expenses and other current liabilities approximate fair value due to their relatively short maturities and market interest rates, if applicable. Refer to Note 4 regarding the fair value of the Company’s available-for-sale securities. Assets and liabilities recorded at fair value on a recurring basis in the consolidated balance sheets are categorized based upon the level of judgment associated with the inputs used to measure their fair values. Fair value is defined as the exchange price that would be received for an asset or an exit price that would be paid to transfer a liability in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. The authoritative guidance on fair value measurements establishes a three-tier fair value hierarchy for disclosure of fair value measurements as follows: Level 1—Observable inputs such as unadjusted, quoted prices in active markets for identical assets or liabilities at the measurement date; Level 2—Inputs (other than quoted prices included in Level 1) are either directly or indirectly observable for the asset or liability. These include quoted prices for similar assets or liabilities in active markets and quoted prices for identical or similar assets or liabilities in markets that are not active; and Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. The following table presents information about the Company’s financial assets that are measured at fair value and indicates the fair value hierarchy of the valuation: March 31, 2021 Total Level 1 Level 2 Level 3 (in thousands) Assets: Money market funds (1) $ 296,117 $ 296,117 $ — $ — Commercial paper (1, 2) 173,006 — 173,006 — U.S. government and agency securities (2) 201,984 — 201,984 — Corporate bonds (2) 11,154 — 11,154 — Total $ 682,261 $ 296,117 $ 386,144 $ — December 31, 2020 Total Level 1 Level 2 Level 3 (in thousands) Assets: Money market funds (1) $ 16,696 $ 16,696 $ — $ — Commercial paper (1, 2) 151,663 — 151,663 — U.S. government and agency securities (1, 2) 270,520 — 270,520 — Corporate bonds (1, 2) 3,200 — 3,200 — Total $ 442,079 $ 16,696 $ 425,383 $ — (1) Included in cash and cash equivalents on the consolidated balance sheets. (2) Included in marketable securities on the consolidated balance sheets. Money market funds are measured at fair value on a recurring basis using quoted prices. U.S. government debt securities, U.S. government agency bonds, commercial paper and corporate bonds are measured at fair value, which is derived from independent pricing sources based on quoted prices in active markets for similar securities. There were no transfers between Levels 1, 2 or 3 for any of the periods presented.

Available-for-sale Securities

Available-for-sale Securities	3 Months Ended
	Mar. 31, 2021
Investments Debt And Equity Securities [Abstract]
Available-for-sale securities	4. Available-for-sale securities The following tables summarize the estimated value of the Company’s available-for-sale marketable securities and cash equivalents and the gross unrealized gains and losses: March 31, 2021 Gross Gross Amortized unrealized unrealized Estimated cost gain loss fair value (in thousands) Marketable securities: Commercial paper $ 116,880 $ 1 $ (21 ) $ 116,860 U.S. government and agency securities 201,894 90 — 201,984 Corporate bonds 11,160 — (6 ) 11,154 Total marketable securities 329,934 91 (27 ) 329,998 Cash equivalents: Money market funds 296,117 — — 296,117 Commercial paper 56,147 — (1 ) 56,146 Total cash equivalents 352,264 — (1 ) 352,263 Total available-for-sale investments $ 682,198 $ 91 $ (28 ) $ 682,261 December 31, 2020 Gross Gross Amortized unrealized unrealized Estimated cost gain loss fair value (in thousands) Marketable securities: Commercial paper $ 69,871 $ — $ (5 ) $ 69,866 U.S. government and agency securities 266,481 131 (5 ) 266,607 Total marketable securities 336,352 131 (10 ) 336,473 Cash equivalents: Money market funds 16,696 — — 16,696 Commercial paper 81,800 — (3 ) 81,797 U.S. government and agency securities 3,913 — — 3,913 Corporate bonds 3,202 — (2 ) 3,200 Total cash equivalents 105,611 — (5 ) 105,606 Total available-for-sale investments $ 441,963 $ 131 $ (15 ) $ 442,079 The amortized cost and estimated fair value of the Company’s available-for-sale securities by contractual maturity are summarized below as of March 31, 2021: March 31, 2021 Gross Gross Amortized unrealized unrealized Estimated cost gain loss fair value (in thousands) Mature in one year or less $ 674,200 $ 90 $ (28 ) $ 674,262 Mature after one year through two years 7,998 1 — 7,999 Total marketable securities $ 682,198 $ 91 $ (28 ) $ 682,261

Balance Sheet Components

Balance Sheet Components	3 Months Ended
	Mar. 31, 2021
Balance Sheet Related Disclosures [Abstract]
Balance Sheet Components	5. Balance sheet components Property and equipment, net Property and equipment, net consists of the following: March 31, December 31, 2021 2020 (in thousands) Laboratory equipment $ 10,563 $ 9,978 Leasehold improvements 7,183 3,387 Computer equipment and software 1,812 1,578 Furniture and fixtures 61 48 Construction in progress — 1,981 19,619 16,972 Less: accumulated depreciation and amortization (8,740 ) (8,070 ) Property and equipment, net $ 10,879 $ 8,902 Depreciation and amortization expense for property and equipment amounted to $0.7 million and $0.6 million for the three months ended March 31, 2021 and 2020, respectively. Accrued expenses and other current liabilities Accrued expenses and other current liabilities consist of the following: March 31, December 31, 2021 2020 (in thousands) Accrued compensation $ 3,237 $ 7,736 Accrued research and development 15,915 10,459 Accrued professional services 1,189 492 Other 104 97 Total accrued expenses and other current liabilities $ 20,445 $ 18,784

Intangible Assets and Goodwill

Intangible Assets and Goodwill	3 Months Ended
	Mar. 31, 2021
Goodwill And Intangible Assets Disclosure [Abstract]
Intangible Assets and Goodwill	6 . Intangible assets and goodwill Intangible assets, net Intangible assets, net consist of the following as of March 31, 2021: Gross value Accumulated amortization Net book value Weighted- average remaining useful life (in thousands) (in years) In-process research and development - RAS Programs $ 55,800 $ — $ 55,800 n/a Developed technology - tri-complex platform 7,480 (2,602 ) 4,878 4.6 Total $ 63,280 $ (2,602 ) $ 60,678 Amortization expense for the three months ended March 31, 2021 and 2020 was $0.3 million and $0.3 million, respectively. As of March 31, 2021, future amortization expense is as follows: Amount (in thousands) 2021 (remaining nine months) $ 801 2022 1,069 2023 1,069 2024 1,069 2025 870 Total $ 4,878 Intangible assets, net consist of the following as of December 31, 2020: Gross value Accumulated amortization Net book value Weighted- average remaining useful life (in thousands) (in years) In-process research and development - RAS Programs $ 55,800 $ — $ 55,800 n/a Developed technology - tri-complex platform 7,480 (2,335 ) 5,145 4.8 Total $ 63,280 $ (2,335 ) $ 60,945 Goodwill The following summarizes the change in the carrying value of goodwill for the three months ended March 31, 2021: Amount (in thousands) Balance at December 31, 2020 $ 14,608 Adjustment — Balance at March 31, 2021 $ 14,608 No impairment has been recognized as of March 31, 2021. Goodwill recorded is not deductible for income tax purposes.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2021
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	7. Commitments and contingencies Leases In January 2015, as amended in September 2016, the Company entered into an operating lease for approximately 42,000 square feet of office and laboratory space located at 700 Saginaw Drive, Redwood City, California (the 700 Building), with a term through April 2023. In April 2020, the Company amended the lease to lease an additional 19,000 square feet of office, laboratory and research and development space located at 300 Saginaw Drive, Redwood City, California (the 300 Building), beginning on December 15, 2020 and ending December 31, 2030, and to extend the Company’s existing lease term for the 700 Building until December 31, 2030. The Company has the option to extend the lease term for the 700 Building and the 300 Building together for an additional ten years after December 31, 2030. The annual base rent for the lease of the 300 Building is $1.2 million until December 31, 2021, after which the annual base rent will increase by approximately 3.5% in each subsequent year of the lease term. The annual base rent for the lease of the 700 Building remains unchanged through April 30, 2023, and increases to $2.8 million for the 12 month period ending April 30, 2024, after which the annual base rent increases by approximately 3.5% in each subsequent year of the lease term. In connection with the lease amendment, the Company issued a letter of credit for $0.9 million, which is included in restricted cash on the consolidated balance sheet as of March 31, 2021 and December 31, 2020, respectively. Through March 31, 2021, the landlord has provided the Company with $3.4 million in tenant improvement allowances for the 700 Building, which were recognized as a lease incentive. The lease amendment provides the Company with an additional tenant improvement allowance of $3.2 million to complete the renovation to the 300 Building, which the Company has determined to be lessee owned. This was also recognized as a lease incentive. Upon the execution of the lease amendment, which was deemed to be a lease modification, the Company re-evaluated the assumptions used during the adoption of ASC 842 for the lease. The Company determined the amendment consists of two separate contracts under ASC 842. One contract is related to a new right-of-use asset for the 300 Building, which is being accounted for as an operating lease, and the other is related to the modification of the original lease term for the 700 Building. As a result, the Company recorded a right-of-use asset of $6.4 million and a lease liability of $9.0 million for the 300 Building and an increase of $14.8 million to the right-of-use asset and lease liability for the 700 Building upon execution of the lease amendment. The Company is recognizing rent expense for both buildings on a straight-line basis through the remaining extended term of the respective leases. As part of the Warp Drive acquisition in October 2018, the Company assumed an operating lease for approximately 22,000 square feet of office and laboratory space located in Cambridge, Massachusetts (the Cambridge Lease), which expires in February 2023, with an option to extend the term through February 2028, subject to certain conditions. In March 2019, the Company fully subleased the Cambridge Lease to Casma Therapeutics, Inc. (Casma), a related party, on financial terms substantially the same as the original lease. The sublease term with Casma is through the remainder of the Cambridge Lease term. The sublease by Casma and related sublease payments by Casma to the Company are fully guaranteed by Third Rock Ventures, LLC, a related party. In conjunction with the Cambridge Lease, the Company issued a letter of credit for $0.2 million, which is included in restricted cash on the condensed consolidated balance sheets as of March 31, 2021 and December 31, 2020. The balance sheet classification of the Company’s lease liabilities was as follows: March 31, December 31, 2021 2020 (in thousands) Operating lease liabilities: Operating lease liability – current $ 3,700 $ 3,672 Operating lease liability – noncurrent 28,294 28,992 Total operating lease liabilities 31,994 32,664 Financing lease liabilities: Accrued expenses and other current liabilities — 19 Total financing lease liabilities — 19 Total lease liabilities $ 31,994 $ 32,683 For the three months ended March 31, 2021 and 2020, operating lease cost was $0.8 million and $0.4 million, respectively, net of sublease income of $0.6 million and $0.4 million, respectively, and tenant improvement allowance credits of $0.1 million and $0.1 million, respectively. The operating cash flows for operating leases were $0.7 million and $0.8 million for the three months ended March 31, 2021 and 2020, respectively. Short-term lease costs were immaterial for the three months ended March 31, 2021 and 2020. As of March 31, 2021, the maturities of the Company’s operating lease liabilities were as follows (in thousands): 2021 (remaining nine months) $ 3,454 2022 5,144 2023 4,173 2024 4,215 2025 4,363 Thereafter 24,213 Total undiscounted lease payments $ 45,562 Less: Imputed interest (12,264 ) Less: Tenant improvement allowance (1,304 ) Total operating lease liabilities $ 31,994 The amounts reflected in the table above include the Company’s lease payments for the Cambridge lease, but do not reflect any offset for the sublease payments the Company is entitled to receive from Casma. The amounts representing the tenant improvement allowance, which are recorded in prepaid expenses and other current assets, are expected to be fully received by the Company within the second quarter of 2021. Operating lease liabilities are based on the net present value of the remaining lease payments over the remaining lease term. In determining the present value of lease payments, the Company uses its incremental borrowing rate. The weighted-average discount rate used to determine the operating lease liability was 7.1%. As of March 31, 2021 and December 31, 2020, the weighted-average remaining lease term was 8.9 years and 9.1 years, respectively. Legal matters From time to time, the Company may be involved in litigation related to claims that arise in the ordinary course of its business activities. The Company accrues for these matters when it is probable that losses will be incurred and these losses can be reasonably estimated. As of March 31, 2021 and December 31, 2020, respectively, the Company does not believe that any such matters, individually or in the aggregate, will have a material adverse effect on the Company’s financial position, results of operations or cash flows. Indemnification The Company enters into standard indemnification arrangements in the ordinary course of business. Pursuant to these arrangements, the Company indemnifies, holds harmless and agrees to reimburse the indemnified parties for losses suffered or incurred by the indemnified party, in connection with any trade secret, copyright, patent or other intellectual property infringement claim by any third party with respect to its technology. The term of these indemnification agreements is generally perpetual any time after the execution of the agreement. The maximum potential amount of future payments the Company could be required to make under these arrangements is not determinable. The Company has not incurred costs to defend lawsuits or settle claims related to these indemnification agreements. As a result, the Company believes the fair value of these agreements is minimal.

Sanofi Collaboration Agreement

Sanofi Collaboration Agreement	3 Months Ended
	Mar. 31, 2021
Collaboration Agreement [Abstract]
Sanofi Collaboration Agreement	8. Sanofi collaboration agreement In June 2018, the Company entered into a collaborative research, development and commercialization agreement (the Sanofi Agreement) with Aventis, Inc. (an affiliate of Sanofi) to research and develop SHP2 inhibitors, including RMC-4630, for any indications. The Sanofi Agreement was assigned to Genzyme Corporation, a Sanofi affiliate, in December 2018. Pursuant to the Sanofi Agreement, the Company granted Sanofi a worldwide, exclusive, sublicensable (subject to the Company’s consent in certain circumstances) license under certain of the Company’s patents and know-how to research, develop, manufacture, use, sell, offer for sale, import and otherwise commercialize SHP2 inhibitors, including RMC-4630, for any and all uses, subject to the Company’s exercise of rights and performance obligations under the Sanofi Agreement. In October 2018, the Company acquired Warp Drive in exchange for issuance of shares of the Company’s Series B redeemable convertible preferred stock and payment of cash. Sanofi was a stockholder of Warp Drive and received the Company’s Series B redeemable convertible preferred stock during the transaction and accordingly became an investor and related party of the Company. As a result of the Company’s underwritten offering of common stock in February 2021, Sanofi’s ownership percentage in the Company decreased and Sanofi is no longer considered a related party. Under the Sanofi Agreement, the Company received a non-refundable, upfront cash payment of $50 million in July 2018 and could also receive up to $520 million in development and regulatory milestone payments, including up to $235 million upon the achievement of specified development milestones and up to $285 million upon the achievement of certain marketing approval milestones. The Company has primary responsibility for early clinical development and for the manufacture of SHP2 inhibitors for Phase 1 and non-registrational Phase 2 clinical trials of RMC-4630 pursuant to an initial development plan. A joint research and development committee is responsible for preparing development plans for other SHP2 inhibitors approved by this committee for development, if any. Sanofi is responsible to reimburse the Company all internal and external costs and expenses to perform the Company’s activities under approved development plans. The Company is also primarily responsible for performing preclinical research on SHP2 inhibitors, pursuant to a research plan that is currently approved through 2021. The research plan and budget beyond 2021 will be determined by a joint research and development committee, over which Sanofi has final decision-making power subject to certain exceptions. Sanofi is responsible to reimburse the Company for all internal and external costs and expenses incurred to perform activities under the approved research plans, with the exception of internal and external research costs and expenses under the approved research plans for 2019 and 2020, for which Sanofi was obligated to reimburse the Company for 80% of such costs. The Company was responsible for 20% of all internal and external research costs incurred under the research plans for 2019 and 2020. Sanofi is responsible to reimburse the Company for all internal and external costs and expenses incurred under the research plan for 2021. In the United States, the Company will share equally with Sanofi the profits and losses applicable to commercialization of SHP2 inhibitor products, pursuant to a profit/loss share agreement that the parties will negotiate based on key terms agreed in the Sanofi Agreement. On a product-by-product basis, Sanofi will also be required to pay the Company tiered royalties on annual net sales of each product outside the United States ranging from high single digit to mid-teen percentages. Unless terminated earlier, the Sanofi Agreement will continue in effect until the later of the expiration of all of Sanofi’s milestone and royalty payment obligations and the expiration of the profit/loss share agreement. Sanofi may terminate the Sanofi Agreement in its entirety or on a country-by-country or product-by-product basis for any reason or for significant safety concerns, upon prior notice to the Company. Sanofi may terminate the Sanofi Agreement in its entirety upon a change of control in the Company, with prior notice. Either party may terminate the Sanofi Agreement if an undisputed material breach by the other party is not cured within a defined period of time, or immediately upon notice for insolvency-related events of the other party. The Company may terminate the Sanofi Agreement after a certain number of years if Sanofi develops a competing program without commencing a registrational clinical trial for a SHP2 inhibitor product candidate, and subject to certain other conditions. The Company may also terminate the Sanofi Agreement at any time, if Sanofi ceases certain critical activities for SHP2 inhibitor product candidates for more than a specified period of time, provided that such cessations of critical activity were not a result of certain specified factors, and subject to certain other conditions. Upon any termination of the Sanofi Agreement with respect to any product or country, all licenses to Sanofi with respect to such product or country shall automatically terminate and all rights generally revert back to the Company. The Company identified the following promises in the agreement (1) the license related to SHP2 inhibitors, (2) the performance of research and development services for Phase 1 clinical studies and Phase 2 clinical trials that are non-registrational clinical trials and (3) the performance of manufacturing services for the non-registrational clinical trials. The Company determined that the license is not distinct from the services within the context of the agreement because the research, development and manufacturing significantly increase the utility of the intellectual property. The intellectual property (IP) related to SHP2 inhibitors, which is proprietary to the Company, is the foundation for the research and development activities. The manufacturing services are a necessary and integral part of the research and development services as they could only be conducted utilizing the outcomes of these services. Given the research and development services under the Sanofi Agreement are expected to involve significant further development of the initial IP, the Company has concluded that the research, development and manufacturing services are not distinct from the license, and thus the license, research and development services and manufacturing services are combined into a single performance obligation. For revenue recognition purposes, the Company determined that the duration of the contract begins on the effective date of the Sanofi Agreement in July 2018 and ends upon completion of the non-registrational clinical trials. The contract duration is defined as the period in which parties to the contract have present enforceable rights and obligations. The Company analyzed the impact of Sanofi terminating the agreement prior to the completion of these trials and determined that there were significant economic costs to Sanofi for doing so. The Company determined that the transaction price of the Sanofi Agreement was $196.1 million as of March 31, 2021. In order to determine the transaction price, the Company evaluated all the payments to be received during the duration of the contract. The Company determined that the $50.0 million upfront payment and $146.1 million of estimated variable consideration for expense reimbursements from Sanofi for agreed upon research and development services as of March 31, 2021 constituted consideration to be included in the transaction price, which is to be allocated to the combined performance obligation. Development and regulatory milestones under the Sanofi Agreement were considered but not included in the transaction price, as it is probable that a significant revenue reversal could occur if they were included. The Company will re-evaluate the transaction price in each reporting period and as uncertain events are resolved or other changes in circumstances occur. The license, research, development and manufacturing services are combined as one performance obligation that will be performed over the duration of the contract, which is from the effective date of the Sanofi Agreement through to the completion of studies. The Company concluded that it would utilize a cost-based input method to measure proportional performance and to calculate the corresponding amount of revenue to recognize. In applying the cost-based input method of revenue recognition, the Company uses actual costs incurred relative to estimated costs to fulfill the combined performance obligation. These costs consist primarily of internal full-time equivalent efforts and third-party costs. Revenue is recognized based on actual costs incurred as a percentage of total estimated costs as the Company completes its performance obligations. The cumulative effect of revisions to estimated costs to complete the Company’s performance obligations will be recorded in the period in which changes are identified and amounts can be reasonably estimated. During the three months ended March 31, 2021 and 2020, the Company recognized $10.1 million and $11.5 million of collaboration revenue associated with this agreement, respectively. As of March 31, 2021 and December 31, 2020, $10.0 million and $12.1 million of deferred revenue is classified as current and $8.1 million and $8.5 million is classified as noncurrent.

Redeemable Convertible Preferre

Redeemable Convertible Preferred Stock	3 Months Ended
	Mar. 31, 2021
Temporary Equity Disclosure [Abstract]
Redeemable Convertible Preferred Stock	9 . Redeemable convertible preferred stock Upon the closing of the IPO in February 2020, all shares of redeemable convertible preferred stock then outstanding converted into 39,600,423 shares of common stock. There were no shares of redeemable convertible preferred stock outstanding as of March 31, 2021 and December 31, 2020, respectively.

Common Stock

Common Stock	3 Months Ended
	Mar. 31, 2021
Stockholders Equity Note [Abstract]
Common Stock	1 0 . Common stock As of March 31, 2021 and December 31, 2020, the Company’s certificate of incorporation authorized the Company to issue 300,000,000 shares of common stock, respectively, at a par value of $0.0001 per share. Each share of common stock is entitled to one vote. The holders of common stock are also entitled to receive dividends whenever funds are legally available and when declared by the Board of Directors, subject to prior rights of the redeemable convertible preferred stockholders. As of March 31, 2021, no dividends have been declared to date. The Company has reserved shares of common stock, on an as-converted basis, for future issuance as follows: March 31, December 31, 2021 2020 Outstanding options to purchase common stock 5,892,121 5,118,979 Unvested restricted stock units of common stock 352,332 85,639 Available for future issuance under the 2020 Incentive Award Plan 6,928,373 4,806,916 Available for issuance under the 2020 Employee Stock Purchase Plan 1,165,719 499,722 Total 14,338,545 10,511,256

Stock-Based Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation	11. Stock-based compensation 2020 Incentive Award Plan In February 2020, the Company adopted the 2020 Equity Incentive Plan (2020 Plan). The 2020 Plan became effective on February 11, 2020. The 2020 Plan provides for a variety of stock-based compensation awards, including stock options, stock appreciation rights, restricted stock awards, restricted stock unit awards, performance bonus awards, performance stock unit awards, dividend equivalents, or other stock or cash based awards. Under the 2020 Plan, the Company generally grants stock-based awards with service-based vesting conditions only. Options and restricted stock unit awards granted typically vest over a four-year period, but may be granted with different vesting terms. Following the effectiveness of the 2020 Plan, the Company will not make any further grants under the 2014 Equity Incentive Plan (2014 Plan). However, the 2014 Plan will continue to govern the terms and conditions of the outstanding awards granted under it. Shares of common stock subject to awards granted under the 2014 Plan that are forfeited or lapse unexercised and which following the effective date of the 2020 Plan are not issued under the 2014 Plan will be available for issuance under the 2020 Plan. As of March 31, 2021, there were 6,928,373 shares of common stock reserved for issuance pursuant to the 2020 Plan. 2014 Equity Incentive Plan In December 2014, the Company adopted the 2014 Plan which provided for the Company to issue restricted common stock, or to grant incentive stock options or nonqualified stock options for the purchase of common stock, to employees, members of the Board of Directors and consultants of the Company under terms and provisions established by the Board of Directors. The Company generally granted stock-based awards with service-based vesting conditions only. Options granted typically vest over a four-year period but may be granted with different vesting terms. The Company allows its employees, non-employees and directors to exercise options granted under the 2014 Plan prior to vesting. The shares related to early exercised stock options are subject to the Company’s lapsing repurchase right upon termination of employment at the original purchase price. In order to vest, the holders are required to provide continued service to the Company. The proceeds are initially recorded in other noncurrent liabilities and are reclassified to common stock and additional paid-in capital as the repurchase right lapses. As of March 31, 2021 and December 31, 2020, there were 95,936 and 130,793 shares, respectively, and $0.2 million and $0.2 million, respectively, recorded in other noncurrent liabilities, related to early exercised shares that were subject to repurchase. 2020 Employee Stock Purchase Plan In February 2020, the Company adopted the 2020 Employee Stock Purchase Plan (2020 ESPP). Under the 2020 ESPP, employees have the ability to purchase shares of the Company’s common stock through payroll deductions at a discount during a series of offering periods of 24 months, each comprised of four six-month purchase periods. The purchase price will be the lower of 85% of the closing trading price per share of the Company’s common stock on the first day of an offering period in which an employee is enrolled or 85% of the closing trading price per share on the purchase date, which will occur on the last trading day of each purchase period. As of March 31, 2021, there have been 29,237 shares purchased under the 2020 ESPP and a total of 1,165,719 shares of common stock were available for future issuance under the ESPP. As of March 31, 2021, there was $1.3 million of unrecognized compensation cost related to the ESPP. Stock options The following summarizes option activity under both the 2020 Plan and the 2014 Plan: Number of Shares underlying options Weighted- average exercise price Weighted- average remaining contractual term Aggregate intrinsic value (in years) (in thousands) Balance, December 31, 2020 5,118,979 $ 7.37 8.25 $ 165,088 Options granted 957,159 42.58 Options exercised (166,897 ) 3.65 Options cancelled (17,120 ) 33.50 Balance, March 31, 2021 5,892,121 $ 13.12 8.36 $ 193,040 Options vested and expected to vest as of March 31, 2021 5,892,121 $ 13.12 8.36 $ 193,040 Options vested and exercisable as of March 31, 2021 2,122,287 $ 4.47 7.61 $ 87,893 As of March 31, 2021, there was $46.3 million of unrecognized stock-based compensation expense related to unvested stock options that is expected to be recognized over a weighted-average period of 2.7 years. Restricted stock units Restricted stock units (RSUs) have been granted to employees and directors. The value of an RSU award is based on the Company’s stock price on the date of grant. The shares underlying the RSU awards are not issued until the RSUs vest. Upon vesting, each RSU converts into one share of the Company’s common stock. The Company has granted RSUs pursuant to the 2020 Plan. Activity under the 2020 Plan with respect to the Company’s RSUs during the three months ended March 31, 2021 was as follows: Number of Shares Weighted- average grant date fair value per share Weighted- average remaining contractual term Aggregate intrinsic value (in years) (in thousands) Balance, December 31, 2020 85,639 $ 35.13 1.73 $ 3,390 Restricted stock units granted 273,471 42.59 Restricted stock units vested (1,798 ) 35.43 Restricted stock units forfeited (4,980 ) 33.42 Balance, March 31, 2021 352,332 $ 40.94 1.96 $ 16,165 Expected to vest as of March 31, 2021 352,332 $ 40.94 1.96 $ 16,165 The number of RSUs vested includes shares of common stock that the Company withheld to satisfy the minimum statutory tax withholding requirements. As of March 31, 2021, there was $13.8 million of total unrecognized compensation cost related to RSUs that is expected to be recognized over a weighted average period of 3.7 years. Stock-based compensation expense Total stock-based compensation expense related to stock options, RSUs and the 2020 ESPP Three Months Ended March 31, 2021 2020 (in thousands) Research and development $ 1,877 $ 893 General and administrative 1,510 674 Total $ 3,387 $ 1,567 Stock-based compensation related to options granted to non-employees was $0.1 million and $0.2 million for the three months ended March 31, 2021 and 2020, respectively.

Net Loss Per Share Attributable

Net Loss Per Share Attributable to Common Stockholders	3 Months Ended
	Mar. 31, 2021
Earnings Per Share [Abstract]
Net Loss Per Share Attributable to Common Stockholders	1 2 . Net loss per share attributable to common stockholders The following table sets forth the computation of basic and diluted net loss per share attributable to common stockholders: Three Months Ended March 31, 2021 2020 (in thousands, except share and per share data) Numerator: Net loss $ (37,176 ) $ (19,519 ) Redeemable convertible preferred stock dividends- undeclared and cumulative — (2,219 ) Net loss attributable to common stockholders $ (37,176 ) $ (21,738 ) Denominator: Weighted-average shares outstanding 70,534,554 29,616,684 Less: Weighted-average unvested restricted shares and shares subject to repurchase (114,478 ) (318,986 ) Weighted-average shares used to compute net loss per share attributable to common stockholders-basic and diluted 70,420,076 29,297,698 Net loss per share attributable to common stockholders-basic and diluted $ (0.53 ) $ (0.74 ) The following outstanding potentially dilutive shares have been excluded from the calculation of diluted net loss per share for the periods presented due to their anti-dilutive effect: As of March 31, 2021 2020 Options to purchase common stock 5,892,121 5,568,324 Options early exercised subject to future vesting 95,936 292,380 Unvested restricted stock units of common stock 352,332 — Expected shares to be purchased under ESPP 94,043 — Total 6,434,432 5,860,704

Related Party Relationships

Related Party Relationships	3 Months Ended
	Mar. 31, 2021
Related Party Transactions [Abstract]
Related Party Relationships	1 3 . Related party relationships Following the Company’s acquisition of Warp Drive, in January 2019, the Company entered into a sublease agreement with Casma to sublease the Cambridge Lease. The sublease by Casma and related sublease payments by Casma to the Company are fully guaranteed by an affiliate of Third Rock Ventures.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Basis of Presentation	Basis of presentation The condensed consolidated financial statements have been prepared in conformity with generally accepted accounting principles in the United States (GAAP) and applicable rules of the Securities and Exchange Commission (SEC) regarding interim financial reporting
Reverse Stock Split	Reverse stock split On February 7, 2020, the Company amended and restated its amended and restated certificate of incorporation to effect a 1-for-4.8661 reverse stock split of the Company’s common stock and redeemable convertible preferred stock. The par value and authorized shares of the common stock and redeemable convertible preferred stock were not adjusted as a result of the reverse stock split. All issued and outstanding common stock, options to purchase common stock and per share amounts contained in the financial statements have been retroactively adjusted to give effect to the reverse stock split for all periods presented.
Use of Estimates	Use of estimates The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. On an ongoing basis, management evaluates its estimates, including those related to revenue recognition, clinical accruals, valuation of in-process research and development and developed technologies, income taxes, useful lives of property and equipment and intangible assets, impairment of goodwill, and stock-based compensation. The extent to which the COVID-19 pandemic may directly or indirectly impact the Company’s business, financial condition and results of operations is highly uncertain and subject to change. The Company considered the potential impact of the COVID-19 pandemic on its estimates and assumptions and there was not a material impact to the Company’s condensed consolidated financial statements as of and for the three months ended March 31, 2021. Actual results could materially differ from the Company’s estimates, and there may be changes to the estimates in future periods .
Concentration of Credit Risk and Other Risks and Uncertainties	Concentration of credit risk and other risks and uncertainties Financial instruments that potentially subject the Company to concentration of credit risk consist of cash, cash equivalents and marketable securities. The Company’s cash is held by two financial institutions in the United States, which management believes to be of high credit quality. The Company invests in money market funds, U.S. government debt securities, U.S. government agency bonds, commercial paper and corporate bonds. The Company has not experienced any losses on its deposits of cash and cash equivalents. The Company is subject to credit risk as its accounts receivable and collaboration revenue are entirely related to its collaboration agreement with Sanofi. See Note 8, “Sanofi collaboration agreement.” The Company’s clinical trial sites for its RMC-4630 and RMC-5552 clinical studies may be affected by the COVID-19 outbreak due to prioritization of hospital resources toward the COVID-19 outbreak, travel or quarantine restrictions imposed by governments, and the inability to access sites for initiation and patient monitoring and enrollment. As a result, patient screening, new patient enrollment, monitoring and data collection may be affected or delayed. The Company is aware that several clinical sites involved in its RMC-4630 clinical studies temporarily stopped or delayed enrolling new patients, with exemptions if appropriate, and it is possible that these or other clinical sites may be similarly affected in the future. These developments may delay the Company’s clinical trial timelines. Some of the Company’s third-party manufacturers which it uses for the supply of materials for product candidates or other materials necessary to manufacture product to conduct preclinical tests and clinical trials and contract research organizations may be impacted by
Leases	Leases The Company determines if an arrangement is, or contains, a lease at inception and then classifies the lease as operating or financing based on the underlying terms and conditions of the contract. Leases with terms greater than one year are initially recognized on the balance sheet as right-of-use assets and lease liabilities based on the present value of lease payments over the expected lease term. The interest rate implicit in lease contracts is typically not readily determinable. As such, the Company utilizes the incremental borrowing rate, which is the rate incurred to borrow, on a collateralized basis, an amount equal to the lease payments over a similar term and in a similar economic environment of the applicable country or region. Variable lease payments are excluded from the right-of-use assets and operating lease liabilities and are recognized in the period in which the obligation for those payments is incurred.
Recently Adopted Accounting Pronouncements	Recent accounting pronouncements From time to time, new accounting pronouncements are issued by the FASB, under its ASC or other standard setting bodies, and adopted by the Company as of the specified effective date, unless otherwise discussed below. Recently adopted accounting pronouncements In December 2019, the Financial Accounting Standards Board (FASB) issued ASU 2019-12, Income Taxes (Topic 740)-Simplifying the Accounting for Income Taxes
Recent Accounting Pronouncements Not Yet Adopted	Recent accounting pronouncements not yet adopted In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments Codification Improvements to Topic 326, Financial Instruments—Credit Losses Financial Instruments—Credit Losses (Topic 326): Targeted Transition Relief In August 2018, the FASB issued ASU No. 2018-15, Intangibles—Goodwill and Other-Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract In October 2020, the FASB issued ASU 2020-08, Codification Improvements to Subtopic 310-20, Receivables-Nonrefundable Fees and Other Costs In October 2020, FASB issued ASU 2020-10, Codification Improvements

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2021
Fair Value Disclosures [Abstract]
Schedule of Financial Assets Measured at Fair Value	The following table presents information about the Company’s financial assets that are measured at fair value and indicates the fair value hierarchy of the valuation: March 31, 2021 Total Level 1 Level 2 Level 3 (in thousands) Assets: Money market funds (1) $ 296,117 $ 296,117 $ — $ — Commercial paper (1, 2) 173,006 — 173,006 — U.S. government and agency securities (2) 201,984 — 201,984 — Corporate bonds (2) 11,154 — 11,154 — Total $ 682,261 $ 296,117 $ 386,144 $ — December 31, 2020 Total Level 1 Level 2 Level 3 (in thousands) Assets: Money market funds (1) $ 16,696 $ 16,696 $ — $ — Commercial paper (1, 2) 151,663 — 151,663 — U.S. government and agency securities (1, 2) 270,520 — 270,520 — Corporate bonds (1, 2) 3,200 — 3,200 — Total $ 442,079 $ 16,696 $ 425,383 $ — (1) Included in cash and cash equivalents on the consolidated balance sheets. (2) Included in marketable securities on the consolidated balance sheets.

Available-for-sale Securities (

Available-for-sale Securities (Tables)	3 Months Ended
	Mar. 31, 2021
Investments Debt And Equity Securities [Abstract]
Summary of Estimated Value of Available-for-sale Securities and Cash Equivalents and Gross Unrealized Gains and Losses	The following tables summarize the estimated value of the Company’s available-for-sale marketable securities and cash equivalents and the gross unrealized gains and losses: March 31, 2021 Gross Gross Amortized unrealized unrealized Estimated cost gain loss fair value (in thousands) Marketable securities: Commercial paper $ 116,880 $ 1 $ (21 ) $ 116,860 U.S. government and agency securities 201,894 90 — 201,984 Corporate bonds 11,160 — (6 ) 11,154 Total marketable securities 329,934 91 (27 ) 329,998 Cash equivalents: Money market funds 296,117 — — 296,117 Commercial paper 56,147 — (1 ) 56,146 Total cash equivalents 352,264 — (1 ) 352,263 Total available-for-sale investments $ 682,198 $ 91 $ (28 ) $ 682,261 December 31, 2020 Gross Gross Amortized unrealized unrealized Estimated cost gain loss fair value (in thousands) Marketable securities: Commercial paper $ 69,871 $ — $ (5 ) $ 69,866 U.S. government and agency securities 266,481 131 (5 ) 266,607 Total marketable securities 336,352 131 (10 ) 336,473 Cash equivalents: Money market funds 16,696 — — 16,696 Commercial paper 81,800 — (3 ) 81,797 U.S. government and agency securities 3,913 — — 3,913 Corporate bonds 3,202 — (2 ) 3,200 Total cash equivalents 105,611 — (5 ) 105,606 Total available-for-sale investments $ 441,963 $ 131 $ (15 ) $ 442,079
Summary of Amortized Cost and Estimated Fair Value of Available-for-sale Securities by Contractual Maturity	The amortized cost and estimated fair value of the Company’s available-for-sale securities by contractual maturity are summarized below as of March 31, 2021: March 31, 2021 Gross Gross Amortized unrealized unrealized Estimated cost gain loss fair value (in thousands) Mature in one year or less $ 674,200 $ 90 $ (28 ) $ 674,262 Mature after one year through two years 7,998 1 — 7,999 Total marketable securities $ 682,198 $ 91 $ (28 ) $ 682,261

Balance Sheet Components (Table

Balance Sheet Components (Tables)	3 Months Ended
	Mar. 31, 2021
Balance Sheet Related Disclosures [Abstract]
Schedule of Property and Equipment, Net	Property and equipment, net consists of the following: March 31, December 31, 2021 2020 (in thousands) Laboratory equipment $ 10,563 $ 9,978 Leasehold improvements 7,183 3,387 Computer equipment and software 1,812 1,578 Furniture and fixtures 61 48 Construction in progress — 1,981 19,619 16,972 Less: accumulated depreciation and amortization (8,740 ) (8,070 ) Property and equipment, net $ 10,879 $ 8,902
Schedule of Accrued Expenses and Other Current Liabilities	Accrued expenses and other current liabilities consist of the following: March 31, December 31, 2021 2020 (in thousands) Accrued compensation $ 3,237 $ 7,736 Accrued research and development 15,915 10,459 Accrued professional services 1,189 492 Other 104 97 Total accrued expenses and other current liabilities $ 20,445 $ 18,784

Intangible Assets and Goodwill

Intangible Assets and Goodwill (Tables)	3 Months Ended
	Mar. 31, 2021
Goodwill And Intangible Assets Disclosure [Abstract]
Schedule of Intangible Assets, Net	Intangible assets, net consist of the following as of March 31, 2021: Gross value Accumulated amortization Net book value Weighted- average remaining useful life (in thousands) (in years) In-process research and development - RAS Programs $ 55,800 $ — $ 55,800 n/a Developed technology - tri-complex platform 7,480 (2,602 ) 4,878 4.6 Total $ 63,280 $ (2,602 ) $ 60,678 Intangible assets, net consist of the following as of December 31, 2020: Gross value Accumulated amortization Net book value Weighted- average remaining useful life (in thousands) (in years) In-process research and development - RAS Programs $ 55,800 $ — $ 55,800 n/a Developed technology - tri-complex platform 7,480 (2,335 ) 5,145 4.8 Total $ 63,280 $ (2,335 ) $ 60,945
Schedule of Future Amortization Expense	As of March 31, 2021, future amortization expense is as follows: Amount (in thousands) 2021 (remaining nine months) $ 801 2022 1,069 2023 1,069 2024 1,069 2025 870 Total $ 4,878
Summary of Change in Carrying Value of Goodwill	The following summarizes the change in the carrying value of goodwill for the three months ended March 31, 2021: Amount (in thousands) Balance at December 31, 2020 $ 14,608 Adjustment — Balance at March 31, 2021 $ 14,608

Commitments and Contingencies (

Commitments and Contingencies (Tables)	3 Months Ended
	Mar. 31, 2021
Commitments And Contingencies Disclosure [Abstract]
Summary of Balance Sheet Classification of Lease Liabilities	The balance sheet classification of the Company’s lease liabilities was as follows: March 31, December 31, 2021 2020 (in thousands) Operating lease liabilities: Operating lease liability – current $ 3,700 $ 3,672 Operating lease liability – noncurrent 28,294 28,992 Total operating lease liabilities 31,994 32,664 Financing lease liabilities: Accrued expenses and other current liabilities — 19 Total financing lease liabilities — 19 Total lease liabilities $ 31,994 $ 32,683
Schedule of Maturities of Operating Lease Liabilities	As of March 31, 2021, the maturities of the Company’s operating lease liabilities were as follows (in thousands): 2021 (remaining nine months) $ 3,454 2022 5,144 2023 4,173 2024 4,215 2025 4,363 Thereafter 24,213 Total undiscounted lease payments $ 45,562 Less: Imputed interest (12,264 ) Less: Tenant improvement allowance (1,304 ) Total operating lease liabilities $ 31,994

Common Stock (Tables)

Common Stock (Tables)	3 Months Ended
	Mar. 31, 2021
Stockholders Equity Note [Abstract]
Schedule of Common Stock Reserved on Converted Basis for Future Issuance	The Company has reserved shares of common stock, on an as-converted basis, for future issuance as follows: March 31, December 31, 2021 2020 Outstanding options to purchase common stock 5,892,121 5,118,979 Unvested restricted stock units of common stock 352,332 85,639 Available for future issuance under the 2020 Incentive Award Plan 6,928,373 4,806,916 Available for issuance under the 2020 Employee Stock Purchase Plan 1,165,719 499,722 Total 14,338,545 10,511,256

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Summary of Total Stock-Based Compensation Expense Related to Stock Options, RSUs and Employee Stock Purchase Plan	Total stock-based compensation expense related to stock options, RSUs and the 2020 ESPP Three Months Ended March 31, 2021 2020 (in thousands) Research and development $ 1,877 $ 893 General and administrative 1,510 674 Total $ 3,387 $ 1,567
2020 Plan and 2014 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Summary of Option Activity Under the Plan	The following summarizes option activity under both the 2020 Plan and the 2014 Plan: Number of Shares underlying options Weighted- average exercise price Weighted- average remaining contractual term Aggregate intrinsic value (in years) (in thousands) Balance, December 31, 2020 5,118,979 $ 7.37 8.25 $ 165,088 Options granted 957,159 42.58 Options exercised (166,897 ) 3.65 Options cancelled (17,120 ) 33.50 Balance, March 31, 2021 5,892,121 $ 13.12 8.36 $ 193,040 Options vested and expected to vest as of March 31, 2021 5,892,121 $ 13.12 8.36 $ 193,040 Options vested and exercisable as of March 31, 2021 2,122,287 $ 4.47 7.61 $ 87,893
2020 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Summary of RSUs Activity Under the Plan	Activity under the 2020 Plan with respect to the Company’s RSUs during the three months ended March 31, 2021 was as follows: Number of Shares Weighted- average grant date fair value per share Weighted- average remaining contractual term Aggregate intrinsic value (in years) (in thousands) Balance, December 31, 2020 85,639 $ 35.13 1.73 $ 3,390 Restricted stock units granted 273,471 42.59 Restricted stock units vested (1,798 ) 35.43 Restricted stock units forfeited (4,980 ) 33.42 Balance, March 31, 2021 352,332 $ 40.94 1.96 $ 16,165 Expected to vest as of March 31, 2021 352,332 $ 40.94 1.96 $ 16,165

Net Loss Per Share Attributab_2

Net Loss Per Share Attributable to Common Stockholders (Tables)	3 Months Ended
	Mar. 31, 2021
Earnings Per Share [Abstract]
Computation of Basic and Diluted Net Loss Per Share Attributable to Common Stockholders	The following table sets forth the computation of basic and diluted net loss per share attributable to common stockholders: Three Months Ended March 31, 2021 2020 (in thousands, except share and per share data) Numerator: Net loss $ (37,176 ) $ (19,519 ) Redeemable convertible preferred stock dividends- undeclared and cumulative — (2,219 ) Net loss attributable to common stockholders $ (37,176 ) $ (21,738 ) Denominator: Weighted-average shares outstanding 70,534,554 29,616,684 Less: Weighted-average unvested restricted shares and shares subject to repurchase (114,478 ) (318,986 ) Weighted-average shares used to compute net loss per share attributable to common stockholders-basic and diluted 70,420,076 29,297,698 Net loss per share attributable to common stockholders-basic and diluted $ (0.53 ) $ (0.74 )
Schedule of Outstanding Potentially Dilutive Shares Excluded from Calculation of Diluted Net Loss Per Share	The following outstanding potentially dilutive shares have been excluded from the calculation of diluted net loss per share for the periods presented due to their anti-dilutive effect: As of March 31, 2021 2020 Options to purchase common stock 5,892,121 5,568,324 Options early exercised subject to future vesting 95,936 292,380 Unvested restricted stock units of common stock 352,332 — Expected shares to be purchased under ESPP 94,043 — Total 6,434,432 5,860,704

Organization - Additional Infor

Organization - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	Feb. 18, 2020	Feb. 28, 2021	Jul. 31, 2020	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Class Of Stock [Line Items]
Accumulated deficit				$ 302,721		$ 265,545
Common stock, shares, issued				73,435,109		66,599,748
Net proceeds from issuance				$ 281,709	$ 253,717
Initial Public Offering
Class Of Stock [Line Items]
Common stock, shares, issued	16,100,000
Common stock, price per share	$ 17
Net proceeds from issuance	$ 250,700
Underwriting discounts and commissions	19,200
Stock issuance expenses	$ 3,800
Underwriter's Option to Purchase Additional Shares
Class Of Stock [Line Items]
Common stock, shares, issued	2,100,000	869,565	900,000
Underwritten Public Offering
Class Of Stock [Line Items]
Common stock, shares, issued		6,666,666	6,900,000
Common stock, price per share		$ 45	$ 26
Net proceeds from issuance		$ 281,100	$ 167,800
Underwriting discounts and commissions		18,000	10,800
Stock issuance expenses		$ 900	$ 800

Summary of Significant Accoun_3

Summary of Significant Accounting Policies - Additional Information (Details)	Feb. 07, 2020	Mar. 31, 2021
Summary Of Significant Accounting Policies [Line Items]
Reverse stock split	0.2055
Reverse stock split, description	1-for-4.8661
ASU 2019-12
Summary Of Significant Accounting Policies [Line Items]
Change in accounting principle, accounting standards update, adoption date		Jan. 1, 2021
Change in accounting principle, accounting standards update, early adoption		true
Change in accounting principle, accounting standards update, adopted		true
Change in accounting principle, accounting standards update, immaterial effect		true

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Financial Assets Measured at Fair Value (Details) - Fair Value, Recurring - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value	$ 682,261	$ 442,079
Money Market Funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value	296,117	16,696
Commercial Paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value	173,006	151,663
U.s. Government And Agency Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value	201,984	270,520
Corporate Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value	11,154	3,200
Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value	296,117	16,696
Level 1 | Money Market Funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value	296,117	16,696
Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value	386,144	425,383
Level 2 | Commercial Paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value	173,006	151,663
Level 2 | U.s. Government And Agency Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value	201,984	270,520
Level 2 | Corporate Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value	$ 11,154	$ 3,200

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Fair value, transfers between Levels 1, 2 or 3, amount	$ 0	$ 0

Available-for-sale Securities -

Available-for-sale Securities - Summary of Estimated Value of Available-for-sale Securities and Cash Equivalents and Gross Unrealized Gains and Losses (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 682,198	$ 441,963
Gross Unrealized Gain	91	131
Gross Unrealized Loss	(28)	(15)
Estimated Fair Value	682,261	442,079
Marketable Securities
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	329,934	336,352
Gross Unrealized Gain	91	131
Gross Unrealized Loss	(27)	(10)
Estimated Fair Value	329,998	336,473
Marketable Securities | Commercial Paper
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	116,880	69,871
Gross Unrealized Gain	1
Gross Unrealized Loss	(21)	(5)
Estimated Fair Value	116,860	69,866
Marketable Securities | U.S. Government and Agency Securities
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	201,894	266,481
Gross Unrealized Gain	90	131
Gross Unrealized Loss		(5)
Estimated Fair Value	201,984	266,607
Marketable Securities | Corporate Bonds
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	11,160
Gross Unrealized Loss	(6)
Estimated Fair Value	11,154
Cash Equivalents
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	352,264	105,611
Gross Unrealized Loss	(1)	(5)
Estimated Fair Value	352,263	105,606
Cash Equivalents | Money Market Funds
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	296,117	16,696
Estimated Fair Value	296,117	16,696
Cash Equivalents | Commercial Paper
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	56,147	81,800
Gross Unrealized Loss	(1)	(3)
Estimated Fair Value	$ 56,146	81,797
Cash Equivalents | U.S. Government and Agency Securities
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost		3,913
Estimated Fair Value		3,913
Cash Equivalents | Corporate Bonds
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost		3,202
Gross Unrealized Loss		(2)
Estimated Fair Value		$ 3,200

Available-for-sale Securities_2

Available-for-sale Securities - Summary of Amortized Cost and Estimated Fair Value of Available-for-sale Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 682,198	$ 441,963
Gross Unrealized Gain	91	131
Gross Unrealized Loss	(28)	(15)
Estimated Fair Value	682,261	$ 442,079
Mature in One Year or Less
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	674,200
Gross Unrealized Gain	90
Gross Unrealized Loss	(28)
Estimated Fair Value	674,262
Mature after One Year through Two Years
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	7,998
Gross Unrealized Gain	1
Estimated Fair Value	$ 7,999

Balance Sheet Components - Sche

Balance Sheet Components - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 19,619	$ 16,972
Less: accumulated depreciation and amortization	(8,740)	(8,070)
Property and equipment, net	10,879	8,902
Laboratory Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	10,563	9,978
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	7,183	3,387
Computer Equipment and Software
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,812	1,578
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 61	48
Construction in Progress
Property Plant And Equipment [Line Items]
Property and equipment, gross		$ 1,981

Balance Sheet Components - Addi

Balance Sheet Components - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Depreciation and amortization expense	$ 0.7	$ 0.6

Balance Sheet Components - Sc_2

Balance Sheet Components - Schedule of Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Accrued Expenses And Other Current Liabilities [Abstract]
Accrued compensation	$ 3,237	$ 7,736
Accrued research and development	15,915	10,459
Accrued professional services	1,189	492
Other	104	97
Total accrued expenses and other current liabilities	$ 20,445	$ 18,784

Intangible Assets and Goodwil_2

Intangible Assets and Goodwill - Schedule of Intangibles Assets, Net (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Goodwill And Intangible Assets Disclosure [Abstract]
In-process research and development - RAS Programs	$ 55,800	$ 55,800
Developed technology - tri-complex platform, Gross value	7,480	7,480
Developed technology - tri-complex platform, Accumulated amortization	(2,602)	(2,335)
Developed technology - tri-complex platform, Net book value	$ 4,878	$ 5,145
Developed technology - tri-complex platform, Weighted-average remaining useful life	4 years 7 months 6 days	4 years 9 months 18 days
Intangible assets, Gross value	$ 63,280	$ 63,280
Intangible assets, Net book value	$ 60,678	$ 60,945

Intangible Assets and Goodwil_3

Intangible Assets and Goodwill - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Goodwill And Intangible Assets Disclosure [Abstract]
Amortization of intangible assets	$ 267,000	$ 267,000
Goodwill impairment	$ 0

Intangible Assets and Goodwil_4

Intangible Assets and Goodwill - Schedule of Future Amortization Expense (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Finite Lived Intangible Assets Future Amortization Expense [Abstract]
2021 (remaining nine months)	$ 801
2022	1,069
2023	1,069
2024	1,069
2025	870
Developed technology - tri-complex platform, Net book value	$ 4,878	$ 5,145

Intangible Assets and Goodwil_5

Intangible Assets and Goodwill - Summary of Change in Carrying Value of Goodwill (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2021USD ($)
Goodwill And Intangible Assets Disclosure [Abstract]
Balance at December 31, 2020	$ 14,608
Adjustment	0
Balance at March 31, 2021	$ 14,608

Commitment and Contingencies -

Commitment and Contingencies - Additional Information (Details) $ in Thousands	1 Months Ended	3 Months Ended
	Apr. 30, 2020USD ($)ft²	Mar. 31, 2021USD ($)	Mar. 31, 2020USD ($)	Dec. 31, 2020USD ($)	Oct. 31, 2018ft²	Jan. 31, 2015ft²
Lessee Lease Description [Line Items]
Operating lease right-of-use asset		$ 26,695		$ 27,435
Operating lease liability		31,994		$ 32,664
Increase in operating lease liability		(670)	$ (775)
Operating lease cost		800	400
Sublease income		600	400
Tenant improvement allowance credits		100	100
Operating cash flows for operating leases		$ 700	$ 800
Operating lease, weighted average discount rate		7.10%		7.10%
Operating lease, weighted average remaining lease term		8 years 10 months 24 days		9 years 1 month 6 days
Redwood City Lease | Restricted Cash
Lessee Lease Description [Line Items]
Letter of credit		$ 900		$ 900
Redwood City Lease | The 700 Building
Lessee Lease Description [Line Items]
Lessee operating lease expiration month and year		2023-04
Area of space leased | ft²						42,000
Lease expiration date	Dec. 31, 2030
Lessee, operating lease, option to extend		option to extend the lease term for the 700 Building and the 300 Building together for an additional ten years after December 31, 2030.
Lessee, operating lease option to extend lease term	10 years
Percentage of increase in annual base rent	3.50%
Operating lease, rent description	The annual base rent for the lease of the 700 Building remains unchanged through April 30, 2023, and increases to $2.8 million for the 12 month period ending April 30, 2024, after which the annual base rent increases by approximately 3.5% in each subsequent year of the lease term.
Tenant improvement allowance		$ 3,400
Redwood City Lease | The 700 Building | ASC 842
Lessee Lease Description [Line Items]
Increase in operating lease right-of-use asset	$ 14,800
Increase in operating lease liability	14,800
Redwood City Lease | The 700 Building | Lease Term Until April 30, 2023
Lessee Lease Description [Line Items]
Annual base rent for lease	$ 2,800
Redwood City Lease | The 300 Building
Lessee Lease Description [Line Items]
Area of space leased | ft²	19,000
Lease beginning date	Dec. 15, 2020
Lease expiration date	Dec. 31, 2030
Lessee, operating lease, option to extend		option to extend the lease term for the 700 Building and the 300 Building together for an additional ten years after December 31, 2030
Lessee, operating lease option to extend lease term	10 years
Percentage of increase in annual base rent	3.50%
Operating lease, rent description	The annual base rent for the lease of the 300 Building is $1.2 million until December 31, 2021, after which the annual base rent will increase by approximately 3.5% in each subsequent year of the lease term.
Tenant improvement allowance		$ 3,200
Redwood City Lease | The 300 Building | ASC 842
Lessee Lease Description [Line Items]
Operating lease right-of-use asset	$ 6,400
Operating lease liability	9,000
Redwood City Lease | The 300 Building | Lease Term Expiring Until December 31, 2021
Lessee Lease Description [Line Items]
Annual base rent for lease	$ 1,200
Cambridge, Massachusetts
Lessee Lease Description [Line Items]
Lessee operating lease expiration month and year		2023-02
Area of space leased | ft²					22,000
Lessee, operating lease, option to extend		Option to extend the term through February 2028
Cambridge, Massachusetts | Restricted Cash
Lessee Lease Description [Line Items]
Letter of credit		$ 200		$ 200

Commitment and Contingencies _2

Commitment and Contingencies - Summary of Balance Sheet Classification of Lease Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Commitments And Contingencies Disclosure [Abstract]
Operating lease liability – current	$ 3,700	$ 3,672
Operating lease liability – noncurrent	28,294	28,992
Total operating lease liabilities	31,994	32,664
Accrued expenses and other current liabilities		$ 19
Finance Lease, Liability, Current, Statement of Financial Position [Extensible List]		Accrued research and development
Total financing lease liabilities		$ 19
Total lease liabilities	$ 31,994	$ 32,683

Commitment and Contingencies _3

Commitment and Contingencies - Schedule of Maturities of Operating Lease Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Commitments And Contingencies Disclosure [Abstract]
2021 (remaining nine months)	$ 3,454
2022	5,144
2023	4,173
2024	4,215
2025	4,363
Thereafter	24,213
Total undiscounted lease payments	45,562
Less: Imputed interest	(12,264)
Less: Tenant improvement allowance	(1,304)
Total operating lease liabilities	$ 31,994	$ 32,664

Sanofi Collaboration Agreement

Sanofi Collaboration Agreement - Additional Information (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Jul. 31, 2018
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue, current	$ 9,964,000		$ 12,111,000
Deferred revenue, noncurrent	8,135,000		$ 8,481,000
Sanofi Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront cash payment received	50,000,000				$ 50,000,000
Maximum development and regulatory milestone payments to be received					520,000,000
Maximum milestone payments receivable upon achievement of specified development milestones					235,000,000
Maximum milestone payments receivable upon achievement of certain marketing approval milestones					$ 285,000,000
Percentage of reimbursement of internal and external research costs and expenses under research plan			80.00%	80.00%
Percentage of other internal and external costs and expenses incurred under research and development plans			20.00%	20.00%
Transaction price	196,100,000
Estimated variable consideration for expense reimbursements upon research and development services	146,100,000
Collaboration revenue recognized	10,100,000	$ 11,500,000
Deferred revenue, current	10,000,000		$ 12,100,000
Deferred revenue, noncurrent	$ 8,100,000		$ 8,500,000

Redeemable Convertible Prefer_2

Redeemable Convertible Preferred Stock - Additional Information (Details) - shares	Mar. 31, 2021	Dec. 31, 2020	Feb. 29, 2020
Temporary Equity [Line Items]
Temporary equity, shares outstanding	0	0
Initial Public Offering
Temporary Equity [Line Items]
Temporary equity, shares outstanding			39,600,423

Common Stock - Additional Infor

Common Stock - Additional Information (Details)	3 Months Ended
	Mar. 31, 2021USD ($)Vote$ / sharesshares	Dec. 31, 2020$ / sharesshares
Stockholders Equity Note [Abstract]
Common stock, shares authorized | shares	300,000,000	300,000,000
Common stock, par or stated value per share | $ / shares	$ 0.0001	$ 0.0001
Common stock, voting rights	Each share of common stock is entitled to one vote
Number of voting rights per common share | Vote	1
Common stock, dividends declared | $	$ 0

Common Stock - Schedule of Comm

Common Stock - Schedule of Common Stock Reserved on Converted Basis for Future Issuance (Details) - shares	Mar. 31, 2021	Dec. 31, 2020
Class Of Stock [Line Items]
Common stock reserved for future issuance, Total	14,338,545	10,511,256
Outstanding Options to Purchase Common Stock
Class Of Stock [Line Items]
Common stock reserved for future issuance, Total	5,892,121	5,118,979
Unvested Restricted Stock Units Of Common Stock
Class Of Stock [Line Items]
Common stock reserved for future issuance, Total	352,332	85,639
Available for Future Issuance under the 2020 Incentive Award Plan
Class Of Stock [Line Items]
Common stock reserved for future issuance, Total	6,928,373	4,806,916
Available for issuance under the 2020 Employee Stock Purchase Plan
Class Of Stock [Line Items]
Common stock reserved for future issuance, Total	1,165,719	499,722

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Details) $ in Thousands	Feb. 29, 2020	Dec. 31, 2014	Mar. 31, 2021USD ($)shares	Mar. 31, 2020USD ($)	Dec. 31, 2020USD ($)shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance, Total | shares			14,338,545		10,511,256
Shares subject to repurchase | shares			95,936		130,793
Exercise price of early exercised shares			$ 200		$ 200
Unrecognized stock-based compensation expense related to unvested stock options			$ 46,300
Unrecognized stock-based compensation expense, weighted-average period of recognition			2 years 8 months 12 days
Stock-based compensation expense			$ 3,387	$ 1,567
Non-employees
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense			$ 100	$ 200
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized stock-based compensation expense, weighted-average period of recognition			3 years 8 months 12 days
Share-based compensation arrangement by share-based payment award, stock awards conversion ratio			1
Unrecognized compensation cost			$ 13,800
2020 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period	4 years
Common stock reserved for future issuance, Total | shares			6,928,373
2014 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period		4 years
2020 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance, Total | shares			1,165,719
Purchase price rate	85.00%
Shares purchased | shares			29,237
Unrecognized compensation cost related to ESPP			$ 1,300

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Option Activity Under the Plan (Details) - 2020 Plan and 2014 Plan - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares underlying options, Beginning balance	5,118,979
Number of Shares underlying options, Options granted	957,159
Number of Shares underlying options, Options exercised	(166,897)
Number of Shares underlying options, Options cancelled	(17,120)
Number of Shares underlying options, Ending balance	5,892,121	5,118,979
Number of Shares underlying options, Options vested and expected to vest	5,892,121
Number of Shares underlying options, Options vested and exercisable	2,122,287
Weighted-average exercise price, Beginning balance	$ 7.37
Weighted-average exercise price, Options granted	42.58
Weighted-average exercise price, Options exercised	3.65
Weighted-average exercise price, Options cancelled	33.50
Weighted-average exercise price, Ending balance	13.12	$ 7.37
Weighted-average exercise price, Options vested and expected to vest	13.12
Weighted-average exercise price, Options vested and exercisable	$ 4.47
Weighted-average remaining contractual term (in years)	8 years 4 months 9 days	8 years 3 months
Weighted-average remaining contractual term, Options vested and expected to vest	8 years 4 months 9 days
Weighted-average remaining contractual term, Options vested and exercisable	7 years 7 months 9 days
Aggregate intrinsic value	$ 193,040	$ 165,088
Aggregate intrinsic value, Options vested and expected to vest	193,040
Aggregate intrinsic value, Options vested and exercisable	$ 87,893

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of RSUs Activity Under the Plan (Details) - 2020 Equity Incentive Plan - Restricted Stock Units (RSUs) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares, Beginning balance	85,639
Number of Shares, Restricted stock units granted	273,471
Number of Shares, Restricted stock units vested	(1,798)
Number of Shares, Restricted stock units forfeited	(4,980)
Number of Shares, Ending balance	352,332	85,639
Number of Shares, Expected to vest	352,332
Weighted-average grant date fair value per share, Beginning balance	$ 35.13
Weighted-average grant date fair value per share, Restricted stock units granted	42.59
Weighted-average grant date fair value per share, Restricted stock units vested	35.43
Weighted-average grant date fair value per share, Restricted stock units forfeited	33.42
Weighted-average grant date fair value per share, Ending balance	40.94	$ 35.13
Weighted-average grant date fair value per share, Expected to vest	$ 40.94
Weighted-average remaining contractual term (in years)	1 year 11 months 15 days	1 year 8 months 23 days
Weighted-average remaining contractual term, Expected to vest	1 year 11 months 15 days
Aggregate intrinsic value	$ 16,165	$ 3,390
Aggregate intrinsic value, Expected to vest	$ 16,165

Stock-Based Compensation - Su_3

Stock-Based Compensation - Summary of Total Stock-Based Compensation Expense Related to Stock Options, RSUs and Employee Stock Purchase Plan (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 3,387	$ 1,567
Research and Development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	1,877	893
General and Administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 1,510	$ 674

Net Loss Per Share Attributab_3

Net Loss Per Share Attributable to Common Stockholders - Computation of Basic and Diluted Net Loss Per Share Attributable to Common Stockholders (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Numerator:
Net loss	$ (37,176)	$ (19,519)
Redeemable convertible preferred stock dividends - undeclared and cumulative		(2,219)
Net loss attributable to common stockholders	$ (37,176)	$ (21,738)
Denominator:
Weighted-average shares outstanding	70,534,554	29,616,684
Less: Weighted-average unvested restricted shares and shares subject to repurchase	(114,478)	(318,986)
Weighted-average shares used to compute net loss per share attributable to common stockholders-basic and diluted	70,420,076	29,297,698
Net loss per share attributable to common stockholders - basic and diluted	$ (0.53)	$ (0.74)

Net Loss Per Share Attributab_4

Net Loss Per Share Attributable to Common Stockholders - Schedule of Outstanding Potentially Dilutive Shares Excluded from Calculation of Diluted Net Loss Per Share (Details) - shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive shares	6,434,432	5,860,704
Option to Purchase Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive shares	5,892,121	5,568,324
Options Early Exercised Subject to Future Vesting
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive shares	95,936	292,380
Unvested Restricted Stock Units Of Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive shares	352,332
Expected Shares To Be Purchased Under ESPP
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive shares	94,043