Praxis Precision Medicines (PRAX) 10-Q 9 May 22 2022 Q1 Quarterly report Financial data

Cover Page

Cover Page - shares	3 Months Ended
	Mar. 31, 2022	May 06, 2022
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2022
Document Transition Report	false
Entity File Number	001-39620
Entity Registrant Name	PRAXIS PRECISION MEDICINES, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	47-5195942
Entity Address, Address Line One	99 High Street
Entity Address, Address Line Two	30th Floor
Entity Address, City or Town	Boston
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02110
City Area Code	617
Local Phone Number	300-8460
Title of 12(b) Security	Common Stock, par value $0.0001 per share
Trading Symbol	PRAX
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		45,511,773
Amendment Flag	false
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q1
Entity Central Index Key	0001689548
Current Fiscal Year End Date	--12-31

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 77,854	$ 138,704
Marketable securities	144,662	137,207
Prepaid expenses and other current assets	11,957	11,498
Total current assets	234,473	287,409
Property and equipment, net	1,142	1,213
Operating lease right-of-use assets	3,473	3,653
Other non-current assets	416	472
Total assets	239,504	292,747
Current liabilities:
Accounts payable	13,269	10,780
Accrued expenses	30,929	26,844
Operating lease liabilities	1,025	810
Total current liabilities	45,223	38,434
Long-term liabilities:
Non-current portion of operating lease liabilities	3,259	3,501
Total liabilities	48,482	41,935
Stockholders’ equity:
Preferred stock, $0.0001 par value; 10,000,000 shares authorized and no shares issued or outstanding as of March 31, 2022 and December 31, 2021	0	0
Common stock, $0.0001 par value; 150,000,000 shares authorized; 45,506,482 shares issued and outstanding as of March 31, 2022, and 45,300,514 shares issued and outstanding as of December 31, 2021	5	5
Additional paid-in capital	576,955	567,598
Accumulated other comprehensive loss	(606)	(176)
Accumulated deficit	(385,332)	(316,615)
Total stockholders’ equity	191,022	250,812
Total liabilities and stockholders’ equity	$ 239,504	$ 292,747

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2022	Dec. 31, 2021
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, authorized (in shares)	10,000,000	10,000,000
Preferred stock, issued (in shares)	0	0
Preferred stock, outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, authorized (in shares)	150,000,000	150,000,000
Common stock, issued (in shares)	45,506,482	45,300,514
Common stock, outstanding (in shares)	45,506,482	45,300,514

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Operating expenses:
Research and development	$ 52,652	$ 17,929
General and administrative	16,197	9,490
Total operating expenses	68,849	27,419
Loss from operations	(68,849)	(27,419)
Other income:
Other income, net	132	46
Total other income	132	46
Net loss	$ (68,717)	$ (27,373)
Net loss per share attributable to common stockholders, basic (in dollars per share)	$ (1.51)	$ (0.71)
Net loss per share attributable to common stockholders, diluted (in dollars per share)	$ (1.51)	$ (0.71)
Weighted average common shares outstanding, basic (in shares)	45,455,179	38,470,710
Weighted average common shares outstanding, diluted (in shares)	45,455,179	38,470,710

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Statement of Comprehensive Income [Abstract]
Net loss	$ (68,717)	$ (27,373)
Net unrealized losses on marketable securities, net of tax	(430)	(86)
Comprehensive loss	$ (69,147)	$ (27,459)

Condensed Consolidated Statem_3

Condensed Consolidated Statements Of Stockholders’ Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Deficit	Accumulated Other Comprehensive Loss
Beginning balance (in shares) at Dec. 31, 2020		38,268,543
Beginning balance at Dec. 31, 2020	$ 287,457	$ 4	$ 437,007	$ (149,554)	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation expense	4,666		4,666
Issuance of common stock upon exercise of stock options (in shares)		352,506
Issuance of common stock upon exercise of stock options	851		851
Change in unrealized loss on marketable securities, net of tax	(86)				(86)
Net loss	(27,373)			(27,373)
Ending balance (in shares) at Mar. 31, 2021		38,621,049
Ending balance at Mar. 31, 2021	$ 265,515	$ 4	442,524	(176,927)	(86)
Beginning balance (in shares) at Dec. 31, 2021	45,300,514	45,300,514
Beginning balance at Dec. 31, 2021	$ 250,812	$ 5	567,598	(316,615)	(176)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation expense	7,886		7,886
Issuance of common stock from at-the-market public offerings (in shares)		70,410
Issuance of common stock from at-the-market public offerings, net of issuance costs	1,368		1,368
Vesting of restricted stock awards (in shares)		81,130
Vesting of restricted stock units	0		0
Shares withheld for taxes for vesting of restricted stock units (in shares)		(17,850)
Shares withheld for taxes for vesting of restricted stock units	$ (230)		(230)
Issuance of common stock upon exercise of stock options (in shares)	72,278	72,278
Issuance of common stock upon exercise of stock options	$ 333		333
Change in unrealized loss on marketable securities, net of tax	(430)				(430)
Net loss	$ (68,717)			(68,717)
Ending balance (in shares) at Mar. 31, 2022	45,506,482	45,506,482
Ending balance at Mar. 31, 2022	$ 191,022	$ 5	$ 576,955	$ (385,332)	$ (606)

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Cash flows from operating activities:
Net loss	$ (68,717)	$ (27,373)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation expense	93	23
Stock-based compensation expense	7,886	4,666
Non-cash operating lease expense	180	183
Amortization of premiums and discounts on marketable securities, net	375	261
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	(1,061)	(2,035)
Accounts payable	2,489	2,208
Accrued expenses	4,616	(3,477)
Operating lease liabilities	(26)	(185)
Other	56	7
Net cash used in operating activities	(54,109)	(25,722)
Cash flows from investing activities:
Purchases of property and equipment	(289)	(4)
Purchases of marketable securities	(83,022)	(140,006)
Maturities of marketable securities	74,761	0
Net cash used in investing activities	(8,550)	(140,010)
Cash flows from financing activities:
Proceeds from at-the-market offerings, net of issuance costs	1,368	0
Payment of issuance costs for at-the-market offerings and initial public offering	(262)	(575)
Payments of tax withholdings related to vesting of restricted stock units	(230)	0
Proceeds from exercise of options to purchase common stock	333	851
Net cash provided by financing activities	1,209	276
Decrease in cash, cash equivalents and restricted cash	(61,450)	(165,456)
Cash, cash equivalents and restricted cash, beginning of period	139,720	297,208
Cash, cash equivalents and restricted cash, end of period	78,270	131,752
Reconciliation of cash, cash equivalents and restricted cash:
Cash and cash equivalents	77,854	131,152
Restricted cash	416	600
Total cash, cash equivalents and restricted cash	78,270	131,752
Supplemental disclosures of non-cash activities:
Purchases of property and equipment included in accrued expenses and accounts payable	$ 0	$ 51

Nature of the Business

Nature of the Business	3 Months Ended
	Mar. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of the Business	Nature of the Business Praxis Precision Medicines, Inc. (“Praxis” or the “Company”) is a clinical-stage biopharmaceutical company translating genetic insights into the development of therapies for central nervous system ("CNS") disorders characterized by neuronal excitation-inhibition imbalance. Normal brain function requires a delicate balance of excitation and inhibition in neuronal circuits, which, when dysregulated, can lead to abnormal function and disease. The Company is applying insights from genetic epilepsies to both rare and more prevalent neurological and psychiatric disorders, using its understanding of shared biological targets and circuits in the brain. The Company applies a deliberate and pragmatic precision approach, leveraging a suite of translational tools including novel transgenic and predictive translational animal models and electrophysiology markers, to enable an efficient path to proof-of-concept in patients. Through this approach, the Company has established a broad CNS portfolio with multiple programs, including product candidates across psychiatric disorders, movement disorders and epilepsy, with three clinical-stage product candidates. Each of the Company's clinical-stage product candidates is advancing in more than one indication and the Company anticipates expansion into additional indications. The Company expects multiple topline readouts from its clinical-stage programs and anticipates the launch of two additional clinical development programs in 2022. In addition, the Company has established a robust pipeline of preclinical stage programs through internal research and in-licensing. Praxis was incorporated in 2015 and commenced operations in 2016. The Company has funded its operations primarily with proceeds from the issuance of redeemable convertible preferred stock and from the sale of common stock through an initial public offering, a follow-on public offering and at-the-market offerings under its shelf registration statement. From inception through March 31, 2022, the Company raised $517.8 million in aggregate cash proceeds from these transactions, net of issuance costs. The Company is subject to risks and uncertainties common to early-stage companies in the biotechnology industry, including but not limited to, risks associated with completing preclinical studies and clinical trials, receiving regulatory approvals for product candidates, development by competitors of new biopharmaceutical products, dependence on key personnel, protection of proprietary technology, compliance with government regulations and the ability to secure additional capital to fund operations. Programs currently under development will require significant additional research and development efforts, including preclinical and clinical testing and regulatory approval, prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel and infrastructure and extensive compliance-reporting capabilities. Even if the Company’s product development efforts are successful, it is uncertain when, if ever, the Company will realize revenue from product sales. Liquidity In accordance with the Financial Accounting Standards Board (“FASB”) Accounting Standards Update (“ASU”) 2014-15, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern (Subtopic 205-40) , the Company has evaluated whether there are conditions and events, considered in the aggregate, that raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date that these condensed consolidated financial statements are issued. The Company has incurred recurring losses since its inception, including a net loss of $68.7 million for the three months ended March 31, 2022. In addition, as of March 31, 2022, the Company had an accumulated deficit of $385.3 million. The Company expects to continue to generate operating losses for the foreseeable future. The Company expects that its cash, cash equivalents and marketable securities as of March 31, 2022 of $222.5 million will be sufficient to fund the operating expenditures and capital expenditure requirements necessary to advance its research efforts and clinical trials for at least one year from the date of issuance of these condensed consolidated financial statements. The future viability of the Company is dependent on its ability to raise additional capital to finance its operations. The Company’s inability to raise capital as and when needed could have a negative impact on its financial condition and ability to pursue its business strategies. There can be no assurance that the

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2022
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Basis of Presentation The accompanying condensed consolidated financial statements have been prepared in conformity with generally accepted accounting principles in the United States of America (“GAAP”). Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification (“ASC”) and ASUs of the FASB. The significant accounting policies used in preparation of these condensed consolidated financial statements for the three months ended March 31, 2022 are consistent with those discussed in Note 2 to the consolidated financial statements included in the Company's 2021 Annual Report on Form 10-K, other than as noted below. Unaudited Interim Condensed Consolidated Financial Information The accompanying condensed consolidated balance sheet as of March 31, 2022, the condensed consolidated statements of operations for the three months ended March 31, 2022 and 2021, the condensed consolidated statements of comprehensive loss for the three months ended March 31, 2022 and 2021, the condensed consolidated statements of cash flows for the three months ended March 31, 2022 and 2021 and the condensed consolidated statements of stockholders’ equity for the three months ended March 31, 2022 and 2021 are unaudited. The unaudited interim financial statements have been prepared on the same basis as the audited annual consolidated financial statements, and in the opinion of management reflect all adjustments, which include only normal recurring adjustments necessary for the fair statement of the Company’s financial position as of March 31, 2022, the results of its operations for the three months ended March 31, 2022 and 2021 and its cash flows for the three months ended March 31, 2022 and 2021. Financial statement disclosures for the three months ended March 31, 2022 and 2021 are condensed and do not include all disclosures required for an annual set of financial statements in accordance with GAAP. The results for the three months ended March 31, 2022 are not necessarily indicative of results to be expected for the year ended December 31, 2022, any other interim periods, or any future year or period. Use of Estimates The preparation of condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of expenses during the reporting periods. Significant estimates and assumptions reflected in these condensed consolidated financial statements include, but are not limited to, accrued and prepaid research and development expenses, stock-based compensation expense and the recoverability of the Company’s net deferred tax assets and related valuation allowance. Estimates are periodically reviewed in light of changes in circumstances, facts and experience. Changes in estimates are recorded in the period in which they become known. Actual results could differ materially from those estimates. Recently Issued Accounting Pronouncements

Marketable Securities

Marketable Securities	3 Months Ended
	Mar. 31, 2022
Investments, Debt and Equity Securities [Abstract]
Marketable Securities	Marketable Securities The following is a summary of the Company's investment portfolio as of March 31, 2022 and December 31, 2021 (in thousands). As of March 31, 2022 Gross Unrealized Estimated Cost Gains Losses Fair Value Available-for-sale securities: Corporate debt securities $ 54,259 $ — $ (438) $ 53,821 Debt securities issued by U.S. government agencies 46,073 2 (70) 46,005 Commercial paper 32,907 — — 32,907 Total securities with a maturity of one year or less $ 133,239 $ 2 $ (508) $ 132,733 Corporate debt securities 12,029 — (100) 11,929 Total securities with a maturity of one to two years $ 12,029 $ — $ (100) $ 11,929 Total available-for-sale securities $ 145,268 $ 2 $ (608) $ 144,662 As of December 31, 2021 Gross Unrealized Estimated Cost Gains Losses Fair Value Available-for-sale securities: Corporate debt securities $ 52,214 $ — $ (31) $ 52,183 Commercial paper 34,993 — — 34,993 Debt securities issued by U.S. government agencies 12,111 — (8) 12,103 Other debt securities 6,398 1 — 6,399 Total securities with a maturity of one year or less $ 105,716 $ 1 $ (39) $ 105,678 Corporate debt securities 31,667 — (138) 31,529 Total securities with a maturity of one to two years $ 31,667 $ — $ (138) $ 31,529 Total available-for-sale securities $ 137,383 $ 1 $ (177) $ 137,207 As of March 31, 2022, the Company had 15 securities with a total fair market value of $90.8 million in an unrealized loss position. As of December 31, 2021, the Company had 14 securities with a total fair market value of $95.8 million in an unrealized loss position. The Company believes that any unrealized losses associated with the decline in value of its securities is temporary and primarily related to the change in market interest rates since purchase, and believes that it is more likely than not that it will be able to hold its debt securities to maturity. Therefore, the Company anticipates a full recovery of the amortized cost basis of its debt securities at maturity and an allowance was not recognized. Securities are evaluated for impairment at the end of each reporting period. The Company did not record any impairment related to its available-for-sale securities during the three months ended March 31, 2022 and 2021.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2022
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements Fair value is defined as the price that would be received to sell an asset in an orderly transaction between market participants at the measurement date. The Company categorizes financial assets measured at fair value based on a fair value hierarchy. The following fair value hierarchy is used to classify financial assets based on observable inputs and unobservable inputs used to value the financial assets: • Level 1: Unadjusted quoted prices in active markets that are accessible at the measurement date for identical assets; • Level 2: Quoted prices for similar assets in active markets, quoted prices in markets that are not active, or inputs which are unobservable, either directly or indirectly, for substantially the full term of the asset; or • Level 3: Prices or valuation techniques that require inputs that are both significant to the valuation of the asset and unobservable. The following tables present information about the Company’s financial assets measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values as of March 31, 2022 and December 31, 2021 (in thousands): As of March 31, 2022 Level 1 Level 2 Level 3 Total Assets: Cash equivalents: Money market funds $ 44,165 $ — $ — $ 44,165 Marketable securities: Corporate debt securities — 65,750 — 65,750 Debt securities issued by U.S. government agencies 46,005 — — 46,005 Commercial paper — 32,907 — 32,907 $ 90,170 $ 98,657 $ — $ 188,827 As of December 31, 2021 Level 1 Level 2 Level 3 Total Assets: Cash equivalents: Money market funds $ 131,372 $ — $ — $ 131,372 Marketable securities: Corporate debt securities — 83,712 — 83,712 Commercial paper — 34,993 — 34,993 Debt securities issued by U.S. government agencies 12,103 — — 12,103 Other debt securities — 6,399 — 6,399 $ 143,475 $ 125,104 $ — $ 268,579

Accrued Expenses

Accrued Expenses	3 Months Ended
	Mar. 31, 2022
Payables and Accruals [Abstract]
Accrued Expenses	Accrued Expenses Accrued expenses consisted of the following (in thousands): March 31, 2022 December 31, 2021 Accrued external research and development expenses $ 26,092 $ 17,763 Accrued personnel-related expenses 2,341 7,180 Accrued other 2,496 1,901 Total accrued expenses $ 30,929 $ 26,844

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and ContingenciesIn May 2021, the Company entered into a sublease agreement for office space located in Boston, Massachusetts that expires on January 31, 2026, with no option to renew or terminate early. The base rent increases by approximately 2% annually. The Company issued a letter of credit to the landlord related to the security deposit, secured by restricted cash, which is reflected within other non-current assets on the accompanying condensed consolidated balance sheets as of March 31, 2022 and December 31, 2021. This lease qualifies as an operating lease.

Common Stock and Preferred Stoc

Common Stock and Preferred Stock	3 Months Ended
	Mar. 31, 2022
Stockholders' Equity Note [Abstract]
Common Stock and Preferred Stock	Common Stock and Preferred Stock Common Stock As of March 31, 2022 and December 31, 2021, the authorized capital stock of the Company included 150,000,000 shares of common stock, $0.0001 par value. As of March 31, 2022 and December 31, 2021, the Company did not hold any treasury shares. Shares Reserved for Future Issuance The Company has reserved the following shares of common stock for future issuance: March 31, December 31, Shares reserved for exercise of outstanding stock options 7,862,576 6,468,501 Shares reserved for future awards under the 2020 Stock Option and Incentive Plan 3,014,484 2,667,780 Shares reserved for future awards under the 2020 Employee Stock Purchase Plan 981,306 654,204 Shares reserved for vesting of restricted stock units 840,277 440,079 Total shares of authorized common stock reserved for future issuance 12,698,643 10,230,564 Preferred Stock As of March 31, 2022 and December 31, 2021, the authorized capital stock of the Company included 10,000,000 shares of undesignated preferred stock, $0.0001 par value.

Stock-Based Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2022
Share-based Payment Arrangement [Abstract]
Stock-Based Compensation	Stock-Based Compensation 2020 Stock Option and Incentive Plan The total number of shares of common stock authorized for issuance under the 2020 Stock Option and Incentive Plan (the "2020 Plan”) as of March 31, 2022 and December 31, 2021 was 7,449,480 shares and 5,184,455 shares, respectively. 2017 Stock Incentive Plan The total number of shares of common stock authorized for issuance under the 2017 Stock Incentive Plan (the "2017 Plan”) as of March 31, 2022 and December 31, 2021 was 5,937,763 shares. Any authorization to issue new options under the 2017 Plan was cancelled upon the effectiveness of the 2020 Plan and no further awards will be granted under the 2017 Plan. 2020 Employee Stock Purchase Plan The total number of shares of common stock authorized for issuance under the 2020 Employee Stock Purchase Plan (the "2020 ESPP”) as of March 31, 2022 and December 31, 2021 was 981,306 shares and 654,204 shares, respectively. Restricted Stock Units The following table summarizes the Company’s restricted stock unit activity: Shares Weighted Unvested as of December 31, 2021 440,079 $ 41.86 Issued 520,328 17.33 Vested (81,130) 51.78 Forfeited (39,000) 23.43 Unvested as of March 31, 2022 840,277 $ 26.57 As of March 31, 2022, total unrecognized compensation cost related to unvested restricted stock units was $20.9 million, which is expected to be recognized over a weighted-average period of 3.32 years. Stock Options The following table summarizes the Company’s stock option activity: Number of Weighted Weighted Aggregate (In years) (In thousands) Outstanding as of December 31, 2021 6,468,501 $ 16.92 Granted 1,631,898 17.63 Exercised (72,278) 4.56 $ 739 Cancelled or Forfeited (165,545) 21.50 Outstanding as of March 31, 2022 7,862,576 $ 17.10 8.68 $ 14,030 Exercisable as of March 31, 2022 2,496,400 $ 13.35 8.03 $ 8,116 Vested and expected to vest as of March 31, 2022 7,862,576 $ 17.10 8.68 $ 14,030 The aggregate intrinsic value of stock options outstanding, exercisable, and vested and expected to vest is calculated as the difference between the exercise price of the underlying stock options and the estimated fair value of the Company’s common stock for those stock options that had exercise prices lower than the estimated fair value of the Company’s common stock at March 31, 2022. The aggregate intrinsic value of stock options exercised is calculated as the difference between the exercise price of the underlying stock options and the estimated fair value of the Company’s common stock on the date of exercise for those stock options that had exercise prices lower than the estimated fair value of the Company’s common stock on the exercise date. Stock Option Valuation The weighted-average assumptions that the Company used in the Black-Scholes option pricing model to determine the grant-date fair value of stock options granted to employees and non-employees on the date of grant were as follows for the three months ended March 31, 2022: Three Months Ended 2022 Risk-free interest rate 1.61 % Expected term (in years) 6.15 Expected volatility 90.36 % Expected dividend yield — % Weighted average grant-date fair value per share $ 13.20 As of March 31, 2022, total unrecognized compensation cost related to unvested stock options was $70.0 million, which is expected to be recognized over a weighted-average period of 2.76 years. Stock-Based Compensation Stock-based compensation expense was allocated as follows (in thousands): Three Months Ended 2022 2021 Research and development $ 3,214 $ 2,318 General and administrative 4,672 2,348 Total stock-based compensation expense $ 7,886 $ 4,666

Net Loss per Share

Net Loss per Share	3 Months Ended
	Mar. 31, 2022
Earnings Per Share [Abstract]
Net Loss per Share	Net Loss per Share The following potential shares of common stock, presented based on amounts outstanding at each period end, were excluded from the calculation of diluted net loss per share for the periods indicated because including them would have been anti-dilutive: Three Months Ended 2022 2021 Outstanding stock options 7,862,576 6,648,367 Unvested restricted stock units 840,277 328,363 Potential shares issuable under the 2020 ESPP 30,341 — 8,733,194 6,976,730

Related Party Transactions

Related Party Transactions	3 Months Ended
	Mar. 31, 2022
Related Party Transactions [Abstract]
Related Party Transactions	Related Party TransactionsOn September 11, 2019, the Company entered into a Cooperation and License Agreement (the “License Agreement”) with RogCon Inc. (“RogCon”). Under the License Agreement, RogCon granted to the Company an exclusive, worldwide license under RogCon’s intellectual property to research, develop and commercialize products for the treatment of all forms of epilepsy and/or neurodevelopmental disorders in each case caused by any mutation of the SCN2A gene. Pursuant to the terms of the License Agreement, the Company will conduct, at its own cost and expense, the research and development activities assigned to it under the associated research plan. In addition, the Company is responsible for reimbursing RogCon for any costs associated with research and development activities RogCon performs at the request of the Company. One of the founders of RogCon became the Company’s General Counsel in June 2020. The Company continues to reimburse RogCon for its out-of-pocket costs incurred for activities performed under the License Agreement. Expenses incurred during all periods presented were not material. As of March 31, 2022, the Company had accrued expenses of $0.3 million due to RogCon under the License Agreement.

Subsequent Events

Subsequent Events	3 Months Ended
	Mar. 31, 2022
Subsequent Events [Abstract]
Subsequent Events	Subsequent EventsThe Company considers events or transactions that occur after the balance sheet date but prior to the issuance of the condensed consolidated financial statements to provide additional evidence for certain estimates or to identify matters that require additional disclosure. The Company has concluded that no subsequent events have occurred that require disclosure.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2022
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying condensed consolidated financial statements have been prepared in conformity with generally accepted accounting principles in the United States of America (“GAAP”). Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification (“ASC”) and ASUs of the FASB. The significant accounting policies used in preparation of these condensed consolidated financial statements for the three months ended March 31, 2022 are consistent with those discussed in Note 2 to the consolidated financial statements included in the Company's 2021 Annual Report on Form 10-K, other than as noted below.
Unaudited Interim Condensed Consolidated Financial Information	Unaudited Interim Condensed Consolidated Financial Information The accompanying condensed consolidated balance sheet as of March 31, 2022, the condensed consolidated statements of operations for the three months ended March 31, 2022 and 2021, the condensed consolidated statements of comprehensive loss for the three months ended March 31, 2022 and 2021, the condensed consolidated statements of cash flows for the three months ended March 31, 2022 and 2021 and the condensed consolidated statements of stockholders’ equity for the three months ended March 31, 2022 and 2021 are unaudited. The unaudited interim financial statements have been prepared on the same basis as the audited annual consolidated financial statements, and in the opinion of management reflect all adjustments, which include only normal recurring adjustments necessary for the fair statement of the Company’s financial position as of March 31, 2022, the results of its operations for the three months ended March 31, 2022 and 2021 and its cash flows for the three months ended March 31, 2022 and 2021. Financial statement disclosures for the three months ended March 31, 2022 and 2021 are condensed and do not include all disclosures required for an annual set of financial statements in accordance with GAAP. The results for the three months ended March 31, 2022 are not necessarily indicative of results to be expected for the year ended December 31, 2022, any other interim periods, or any future year or period.
Use of Estimates	Use of Estimates The preparation of condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of expenses during the reporting periods. Significant estimates and assumptions reflected in these condensed consolidated financial statements include, but are not limited to, accrued and prepaid research and development expenses, stock-based compensation expense and the recoverability of the Company’s net deferred tax assets and related valuation allowance. Estimates are periodically reviewed in light of changes in circumstances, facts and experience. Changes in estimates are recorded in the period in which they become known. Actual results could differ materially from those estimates.
Recently Issued Accounting Pronouncements	Recently Issued Accounting PronouncementsThe Company does not expect any recently issued accounting pronouncements to have a material impact on its financial statements

Marketable Securities (Tables)

Marketable Securities (Tables)	3 Months Ended
	Mar. 31, 2022
Investments, Debt and Equity Securities [Abstract]
Debt Securities, Available-for-sale	The following is a summary of the Company's investment portfolio as of March 31, 2022 and December 31, 2021 (in thousands). As of March 31, 2022 Gross Unrealized Estimated Cost Gains Losses Fair Value Available-for-sale securities: Corporate debt securities $ 54,259 $ — $ (438) $ 53,821 Debt securities issued by U.S. government agencies 46,073 2 (70) 46,005 Commercial paper 32,907 — — 32,907 Total securities with a maturity of one year or less $ 133,239 $ 2 $ (508) $ 132,733 Corporate debt securities 12,029 — (100) 11,929 Total securities with a maturity of one to two years $ 12,029 $ — $ (100) $ 11,929 Total available-for-sale securities $ 145,268 $ 2 $ (608) $ 144,662 As of December 31, 2021 Gross Unrealized Estimated Cost Gains Losses Fair Value Available-for-sale securities: Corporate debt securities $ 52,214 $ — $ (31) $ 52,183 Commercial paper 34,993 — — 34,993 Debt securities issued by U.S. government agencies 12,111 — (8) 12,103 Other debt securities 6,398 1 — 6,399 Total securities with a maturity of one year or less $ 105,716 $ 1 $ (39) $ 105,678 Corporate debt securities 31,667 — (138) 31,529 Total securities with a maturity of one to two years $ 31,667 $ — $ (138) $ 31,529 Total available-for-sale securities $ 137,383 $ 1 $ (177) $ 137,207

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2022
Fair Value Disclosures [Abstract]
Summary of Financial Assets Measured At Fair Value On A Recurring Basis	The following tables present information about the Company’s financial assets measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values as of March 31, 2022 and December 31, 2021 (in thousands): As of March 31, 2022 Level 1 Level 2 Level 3 Total Assets: Cash equivalents: Money market funds $ 44,165 $ — $ — $ 44,165 Marketable securities: Corporate debt securities — 65,750 — 65,750 Debt securities issued by U.S. government agencies 46,005 — — 46,005 Commercial paper — 32,907 — 32,907 $ 90,170 $ 98,657 $ — $ 188,827 As of December 31, 2021 Level 1 Level 2 Level 3 Total Assets: Cash equivalents: Money market funds $ 131,372 $ — $ — $ 131,372 Marketable securities: Corporate debt securities — 83,712 — 83,712 Commercial paper — 34,993 — 34,993 Debt securities issued by U.S. government agencies 12,103 — — 12,103 Other debt securities — 6,399 — 6,399 $ 143,475 $ 125,104 $ — $ 268,579

Accrued Expenses (Tables)

Accrued Expenses (Tables)	3 Months Ended
	Mar. 31, 2022
Payables and Accruals [Abstract]
Schedule of Accrued Liabilities	Accrued expenses consisted of the following (in thousands): March 31, 2022 December 31, 2021 Accrued external research and development expenses $ 26,092 $ 17,763 Accrued personnel-related expenses 2,341 7,180 Accrued other 2,496 1,901 Total accrued expenses $ 30,929 $ 26,844

Common Stock and Preferred St_2

Common Stock and Preferred Stock (Tables)	3 Months Ended
	Mar. 31, 2022
Stockholders' Equity Note [Abstract]
Summary of Common Stock Reserved For Future Issuance	The Company has reserved the following shares of common stock for future issuance: March 31, December 31, Shares reserved for exercise of outstanding stock options 7,862,576 6,468,501 Shares reserved for future awards under the 2020 Stock Option and Incentive Plan 3,014,484 2,667,780 Shares reserved for future awards under the 2020 Employee Stock Purchase Plan 981,306 654,204 Shares reserved for vesting of restricted stock units 840,277 440,079 Total shares of authorized common stock reserved for future issuance 12,698,643 10,230,564

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2022
Share-based Payment Arrangement [Abstract]
Summary of Restricted Stock Activity	The following table summarizes the Company’s restricted stock unit activity: Shares Weighted Unvested as of December 31, 2021 440,079 $ 41.86 Issued 520,328 17.33 Vested (81,130) 51.78 Forfeited (39,000) 23.43 Unvested as of March 31, 2022 840,277 $ 26.57
Summary of Stock Option Activity	The following table summarizes the Company’s stock option activity: Number of Weighted Weighted Aggregate (In years) (In thousands) Outstanding as of December 31, 2021 6,468,501 $ 16.92 Granted 1,631,898 17.63 Exercised (72,278) 4.56 $ 739 Cancelled or Forfeited (165,545) 21.50 Outstanding as of March 31, 2022 7,862,576 $ 17.10 8.68 $ 14,030 Exercisable as of March 31, 2022 2,496,400 $ 13.35 8.03 $ 8,116 Vested and expected to vest as of March 31, 2022 7,862,576 $ 17.10 8.68 $ 14,030
Schedule of Fair Value of Stock Option Awards on the Grant Date Using the Black-Scholes Option Valuation Model	The weighted-average assumptions that the Company used in the Black-Scholes option pricing model to determine the grant-date fair value of stock options granted to employees and non-employees on the date of grant were as follows for the three months ended March 31, 2022: Three Months Ended 2022 Risk-free interest rate 1.61 % Expected term (in years) 6.15 Expected volatility 90.36 % Expected dividend yield — % Weighted average grant-date fair value per share $ 13.20
Summary of Stock-Based Compensation Expense	Stock-based compensation expense was allocated as follows (in thousands): Three Months Ended 2022 2021 Research and development $ 3,214 $ 2,318 General and administrative 4,672 2,348 Total stock-based compensation expense $ 7,886 $ 4,666

Net Loss per Share (Tables)

Net Loss per Share (Tables)	3 Months Ended
	Mar. 31, 2022
Earnings Per Share [Abstract]
Summary of Antidilutive Securities Excluded From Computation of Earnings Per Share	The following potential shares of common stock, presented based on amounts outstanding at each period end, were excluded from the calculation of diluted net loss per share for the periods indicated because including them would have been anti-dilutive: Three Months Ended 2022 2021 Outstanding stock options 7,862,576 6,648,367 Unvested restricted stock units 840,277 328,363 Potential shares issuable under the 2020 ESPP 30,341 — 8,733,194 6,976,730

Nature of the Business - Additi

Nature of the Business - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Proceeds from issuance or sale of equity	$ 517,800
Net loss	68,717	$ 27,373
Accumulated deficit	385,332		$ 316,615
Cash, cash equivalents, and short-term investments	$ 222,500

Marketable Securities - Investm

Marketable Securities - Investment Profile (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, cost, current	$ 133,239	$ 105,716
Available-for-Sale, cost, noncurrent	12,029	31,667
Total available-for-sale securities, cost	145,268	137,383
Available-for-sale, gross unrealized gain, current, before tax	2	1
Available-for-sale, gross unrealized gain, noncurrent, before tax	0	0
Total available-for-sale securities, gross unrealized gains	2	1
Available-for-sale, gross unrealized loss, current, before tax	(508)	(39)
Available-for-sale, gross unrealized loss, noncurrent, before tax	(100)	(138)
Total available-for-sale, gross unrealized losses	(608)	(177)
Estimated fair value, available-for-sale, current	132,733	105,678
Estimated fair value, available-for-sale, noncurrent	11,929	31,529
Total available-for-sale securities, estimated fair value	144,662	137,207
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, cost, current	54,259	52,214
Available-for-Sale, cost, noncurrent	12,029	31,667
Available-for-sale, gross unrealized gain, current, before tax	0	0
Available-for-sale, gross unrealized gain, noncurrent, before tax	0	0
Available-for-sale, gross unrealized loss, current, before tax	(438)	(31)
Available-for-sale, gross unrealized loss, noncurrent, before tax	(100)	(138)
Estimated fair value, available-for-sale, current	53,821	52,183
Estimated fair value, available-for-sale, noncurrent	11,929	31,529
Debt securities issued by U.S. government agencies
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, cost, current	46,073	12,111
Available-for-sale, gross unrealized gain, current, before tax	2	0
Available-for-sale, gross unrealized loss, current, before tax	(70)	(8)
Estimated fair value, available-for-sale, current	46,005	12,103
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, cost, current	32,907	34,993
Available-for-sale, gross unrealized gain, current, before tax	0	0
Available-for-sale, gross unrealized loss, current, before tax	0	0
Estimated fair value, available-for-sale, current	$ 32,907	34,993
Other debt securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, cost, current		6,398
Available-for-sale, gross unrealized gain, current, before tax		1
Available-for-sale, gross unrealized loss, current, before tax		0
Estimated fair value, available-for-sale, current		$ 6,399

Marketable Securities - Additio

Marketable Securities - Additional Information (Details) $ in Millions	Mar. 31, 2022USD ($)security	Dec. 31, 2021USD ($)security
Investments, Debt and Equity Securities [Abstract]
Number of securities | security	15	14
Securities, unrealized loss position, fair value | $	$ 90.8	$ 95.8

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Financial Assets Measured at Fair Value on a Recurring Basis (Details) - Fair Value, Recurring - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	$ 188,827	$ 268,579
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	90,170	143,475
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	98,657	125,104
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	0	0
Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	44,165	131,372
Money market funds | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	44,165	131,372
Money market funds | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	0	0
Money market funds | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	0	0
Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	65,750	83,712
Corporate debt securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	0
Corporate debt securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	65,750	83,712
Corporate debt securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	0
Debt securities issued by U.S. government agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	46,005	12,103
Debt securities issued by U.S. government agencies | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	46,005	12,103
Debt securities issued by U.S. government agencies | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	0
Debt securities issued by U.S. government agencies | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	0
Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	32,907	34,993
Commercial paper | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	0
Commercial paper | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	32,907	34,993
Commercial paper | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	$ 0	0
Other debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments		6,399
Other debt securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments		0
Other debt securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments		6,399
Other debt securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments		$ 0

Accrued Expenses - Summary of A

Accrued Expenses - Summary of Accrued Expenses (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Payables and Accruals [Abstract]
Accrued external research and development expenses	$ 26,092	$ 17,763
Accrued personnel-related expenses	2,341	7,180
Accrued other	2,496	1,901
Total accrued expenses	$ 30,929	$ 26,844

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details)	May 31, 2021
Office Space in Boston Massachusetts
Loss Contingencies [Line Items]
Percentage increase in annual base rent	2.00%

Common Stock and Preferred St_3

Common Stock and Preferred Stock - Additional Information (Details) - $ / shares	Mar. 31, 2022	Dec. 31, 2021
Schedule Of Common Stock Reserved For Future Issuance [Abstract]
Common stock, authorized (in shares)	150,000,000	150,000,000
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Treasury shares	0	0
Preferred stock, authorized (in shares)	10,000,000	10,000,000
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001

Common Stock and Preferred St_4

Common Stock and Preferred Stock - Summary of Common Stock Reserved For Future Issuance (Details) - shares	Mar. 31, 2022	Dec. 31, 2021
Schedule Of Common Stock Reserved For Future Issuance [Line Items]
Common stock reserved for future issuance (in shares)	12,698,643	10,230,564
Shares reserved for exercise of outstanding stock options
Schedule Of Common Stock Reserved For Future Issuance [Line Items]
Common stock reserved for future issuance (in shares)	7,862,576	6,468,501
Share-based payment arrangement | Shares reserved for future awards under the 2020 Stock Option and Incentive Plan
Schedule Of Common Stock Reserved For Future Issuance [Line Items]
Common stock reserved for future issuance (in shares)	3,014,484	2,667,780
Share-based payment arrangement | Shares reserved for future awards under the 2020 Employee Stock Purchase Plan
Schedule Of Common Stock Reserved For Future Issuance [Line Items]
Common stock reserved for future issuance (in shares)	981,306	654,204
Shares reserved for vesting of restricted stock units
Schedule Of Common Stock Reserved For Future Issuance [Line Items]
Common stock reserved for future issuance (in shares)	840,277	440,079

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Unvested Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost related to unvested restricted stock units	$ 20.9
Weighted-average period (in years)	3 years 3 months 25 days
Shares reserved for exercise of outstanding stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to unvested stock based awards	$ 70
Weighted-average period (in years)	2 years 9 months 3 days
2020 Employee Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	7,449,480	5,184,455
2017 Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	5,937,763	5,937,763
2020 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	981,306	654,204

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Restricted Stock Activity (Details) - Unvested restricted stock units	3 Months Ended
	Mar. 31, 2022$ / sharesshares
Shares
Beginning balance (in shares) | shares	440,079
Issued (in shares) | shares	520,328
Vested (in shares) | shares	(81,130)
Forfeited (in shares) | shares	(39,000)
Ending balance (in shares) | shares	840,277
Weighted Average Grant Date Fair Value
Unvested beginning balance (in dollars per share) | $ / shares	$ 41.86
Issued (in dollars per share) | $ / shares	17.33
Vested (in dollars per share) | $ / shares	51.78
Forfeitures (in dollars per shares) | $ / shares	23.43
Unvested ending balance (in dollars per share) | $ / shares	$ 26.57

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of Stock Option Activity (Details) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2022USD ($)$ / sharesshares
Number of Shares
Beginning balance (in shares) | shares	6,468,501
Granted (in shares) | shares	1,631,898
Exercised (in shares) | shares	(72,278)
Canceled or forfeited (in shares) | shares	(165,545)
Ending balance (in shares) | shares	7,862,576
Number of shares exercisable (in shares) | shares	2,496,400
Vested and expected to vest (in shares) | shares	7,862,576
Weighted Average Exercise Price per Share
Beginning balance (in dollars per share) | $ / shares	$ 16.92
Granted (in dollars per share) | $ / shares	17.63
Exercised (in dollars per share) | $ / shares	4.56
Cancelled or forfeited (in dollars per share) | $ / shares	21.50
Ending balance (in dollars per share) | $ / shares	17.10
Exercisable (in dollars per share) | $ / shares	13.35
Vested and expected to vest (in dollars per share) | $ / shares	$ 17.10
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted average remaining contractual term outstanding	8 years 8 months 4 days
Weighted average remaining contractual term exercisable	8 years 10 days
Weighted average remaining contractual term vested and expected to vest	8 years 8 months 4 days
Aggregate intrinsic value exercised | $	$ 739
Aggregate intrinsic value outstanding | $	14,030
Aggregate intrinsic value exercisable | $	8,116
Aggregate intrinsic value vested and expected to vest | $	$ 14,030

Stock-Based Compensation - Sche

Stock-Based Compensation - Schedule of Fair Value of Stock Option Awards on the Grant Date Using the Black-Scholes Option Valuation Model (Details)	3 Months Ended
	Mar. 31, 2022$ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	1.61%
Expected term (in years)	6 years 1 month 24 days
Expected volatility	90.36%
Expected dividend yield	0.00%
Shares reserved for exercise of outstanding stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant-date fair value per share (in dollars per share)	$ 13.20

Stock-Based Compensation - Su_3

Stock-Based Compensation - Summary of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	$ 7,886	$ 4,666
Research and development
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	3,214	2,318
General and administrative
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	$ 4,672	$ 2,348

Net Loss per Share - Summary of

Net Loss per Share - Summary of antidilutive securities excluded from computation of earnings per share (Details) - shares	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	8,733,194	6,976,730
Outstanding stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	7,862,576	6,648,367
Unvested restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	840,277	328,363
Potential shares issuable under the 2020 ESPP
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	30,341	0

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Details) $ in Millions	Mar. 31, 2022USD ($)
RogCon Inc.
Related Party Transaction [Line Items]
Due to related parties	$ 0.3