Imago BioSciences (IMGO) 10-K 24 Mar 22 2021 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2021	Mar. 11, 2022	Jun. 30, 2021
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Entity Registrant Name	Imago BioSciences, Inc.
Entity Central Index Key	0001623715
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity File Number	001-40604
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	45-4915810
Entity Address, Address Line One	329 Oyster Point Blvd.
Entity Address, Address Line Two	3rd Floor
Entity Address, City or Town	South San Francisco
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94080
City Area Code	415
Local Phone Number	529-5055
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
ICFR Auditor Attestation Flag	false
Entity Common Stock, Shares Outstanding		33,706,657
Entity Public Float			$ 0
Document Annual Report	true
Document Transition Report	false
Title of 12(b) Security	Common Stock, par value $0.0001 per share
Trading Symbol	IMGO
Security Exchange Name	NASDAQ
Auditor Firm ID	34
Auditor Name	Deloitte & Touche LLP
Auditor Location	San Francisco, California
Documents Incorporated By Reference	Part III incorporates certain information by reference from the registrant’s proxy statement for the 2022 Annual Meeting of Shareholders. Such proxy statement will be filed no later than 120 days after the close of the registrant’s fiscal year ended December 31, 2021.

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 11,226	$ 19,266
Short-term investments	206,184	57,375
Prepaid expenses and other current assets	3,894	1,181
Total current assets	221,304	77,822
Property and equipment, net	2	8
Long-term investments		19,689
Other long-term assets	3,480	1,414
Total assets	224,786	98,933
Current liabilities:
Accounts payable	3,459	1,379
Accrued and other current liabilities	6,633	3,726
Total current liabilities	10,092	5,105
Commitments and contingencies (Note 6)
Convertible preferred stock, $0.0001 par value; 0 and 180,059,639 shares authorized, as of December 31, 2021 and 2020, respectively; 0 and 21,435,632 issued and outstanding as of December 31, 2021 and 2020, respectively; aggregate liquidation preference of $0 as of December 31, 2021	0	162,612
Stockholders' equity (deficit):
Preferred stock, $0.0001 par value; 10,000,000 and 0 shares authorized as of December 31, 2021 and 2020, respectively; 0 issued and outstanding as of December 31, 2021 and 2020, respectively	0	0
Common stock, $0.0001 par value; 300,000,000 and 228,300,000 shares authorized as of December 31, 2021 and 2020, respectively; 33,531,743 and 1,030,023 shares issued and outstanding as of December 31, 2021 and 2020, respectively	3	0
Additional paid-in capital	327,387	1,561
Accumulated other comprehensive income (loss)	(43)	(3)
Accumulated deficit	(112,653)	(70,342)
Total stockholders' equity (deficit)	214,694	(68,784)
Total liabilities, convertible preferred stock and stockholders' equity (deficit)	$ 224,786	$ 98,933

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Convertible preferred stock, par value per share	$ 0.0001	$ 0.0001
Convertible preferred stock, shares authorized	0	180,059,639
Convertible preferred stock, shares issued	0	21,435,632
Convertible preferred stock, shares outstanding	0	21,435,632
Convertible preferred stock, liquidation preference	$ 0	$ 165,500
Preferred stock, par value per share	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	10,000,000	0
Preferred stock shares issued	0	0
Preferred stock shares outstanding	0	0
Common stock, par value per share	$ 0.0001	$ 0.0001
Common stock, shares authorized	300,000,000	228,300,000
Common stock shares issued	33,531,743	1,030,023
Common stock shares outstanding	33,531,743	1,030,023

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Operating expenses:
Research and development	$ 32,261,000	$ 14,896,000
General and administrative	10,263,000	3,176,000
Total operating expenses	42,524,000	18,072,000
Loss from operations	(42,524,000)	(18,072,000)
Other income (expense), net:
Interest income	314,000	48,000
Change in fair value of convertible preferred stock tranche liability		214,000
Other expense, net	(99,000)	(20,000)
Total other income, net	215,000	242,000
Loss before income tax expense	(42,309,000)	(17,830,000)
Income tax expense	(2,000)	(3,000)
Net loss	$ (42,311,000)	$ (17,833,000)
Net loss per share, basic and diluted	$ (2.70)	$ (17.49)
Weighted-average shares used in computing net loss per share, basic and diluted	15,696,314	1,019,615

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Statement of Comprehensive Income [Abstract]
Net loss	$ (42,311)	$ (17,833)
Other comprehensive income (loss):
Unrealized loss on available-for-sale securities	(40)	(4)
Comprehensive loss	$ (42,351)	$ (17,837)

Consolidated Statements of Conv

Consolidated Statements of Convertible Preferred Stock and Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income	Accumulated Deficit	Convertible Preferred Stock	Series B Convertible Preferred Stock	Series C Convertible Preferred Stock	Initial Public Offering	Initial Public OfferingCommon Stock	Initial Public OfferingAdditional Paid-in Capital	Initial Public OfferingConvertible Preferred Stock	Private Placement	Private PlacementCommon Stock	Private PlacementAdditional Paid-in Capital
Temporary equity, beginning balance, shares at Dec. 31, 2019						9,020,460
Temporary equity, beginning balance at Dec. 31, 2019						$ 54,771
Beginning balance, shares at Dec. 31, 2019		1,018,119
Beginning balance at Dec. 31, 2019	$ (51,402)		$ 1,106	$ 1	$ (52,509)
Issuance of convertible preferred stock, net of issuance costs, shares							4,529,931	7,885,241
Issuance of convertible preferred stock, net of issuance costs							$ 28,139	$ 79,702
Exercise of stock options, shares		11,904
Exercise of stock options	29		29
Stock-based compensation	426		426
Other comprehensive income	(4)			(4)
Net loss	$ (17,833)				(17,833)
Temporary equity, ending balance, shares at Dec. 31, 2020	21,435,632					21,435,632	7,878,135	7,885,241
Temporary equity, ending balance at Dec. 31, 2020	$ 162,612					$ 162,612	$ 44,895	$ 79,702
Ending balance, shares at Dec. 31, 2020	1,030,023	1,030,023
Ending balance at Dec. 31, 2020	$ (68,784)		1,561	(3)	(70,342)
Conversion of convertible preferred stock to common stock upon initial public offering, shares										21,435,632		(21,435,632)
Conversion of convertible preferred stock to common stock upon initial public offering									$ 162,612	$ 2	$ 162,610	$ (162,612)
Issuance of common stock, shares										9,660,000				1,250,000
Issuance of common stock									$ 140,486	$ 1	$ 140,485		$ 20,000		$ 20,000
Exercise of stock options, shares		156,088
Exercise of stock options	506		506
Stock-based compensation	2,225		2,225
Other comprehensive income	(40)			(40)
Net loss	$ (42,311)				(42,311)
Temporary equity, ending balance, shares at Dec. 31, 2021	0
Temporary equity, ending balance at Dec. 31, 2021	$ 0
Ending balance, shares at Dec. 31, 2021	33,531,743	33,531,743
Ending balance at Dec. 31, 2021	$ 214,694	$ 3	$ 327,387	$ (43)	$ (112,653)

Consolidated Statements of Co_2

Consolidated Statements of Convertible Preferred Stock and Stockholders' Equity (Deficit) (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Settlement of preferred stock tranche liability		$ 2,281
Initial Public Offering | Common Stock
Stock issuance costs	$ 3,255
Series B Convertible Preferred Stock
Temporary equity, stock issuance costs		17
Series C Convertible Preferred Stock
Temporary equity, stock issuance costs		$ 298

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Cash flows from operating activities:
Net loss	$ (42,311,000)	$ (17,833,000)
Adjustments to reconcile net loss to net cash used in operating activities:
Amortization of premium and discounts on available-for-sale investments	109,000	6,000
Depreciation and amortization	6,000	1,000
Change in fair value of convertible preferred stock tranche liability		(214,000)
Stock-based compensation	2,225,000	426,000
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	(2,710,000)	(393,000)
Other long-term assets	(2,051,000)	(1,403,000)
Accounts payable	2,062,000	8,000
Accrued expenses and other current liabilities	2,907,000	2,460,000
Net cash used in operating activities	(39,763,000)	(16,942,000)
Cash flows from investing activities:
Purchases of property and equipment		(9,000)
Purchases of available-for-sale investments	(208,422,000)	(81,083,000)
Proceeds from maturities of available-for-sale investments	79,153,000	6,750,000
Net cash used in investing activities	(129,269,000)	(74,342,000)
Cash flows from financing activities:
Payments of offering costs related to initial public offering	(3,255,000)
Proceeds from exercise of stock options	506,000	29,000
Net cash provided by financing activities	160,992,000	105,589,000
Net (decrease) increase in cash and cash equivalents	(8,040,000)	14,305,000
Cash and cash equivalents at beginning of period	19,266,000	4,961,000
Cash and cash equivalents at end of period	11,226,000	19,266,000
Supplemental cash flow disclosure:
Cash paid for taxes	74,000	14,000
Supplemental disclosure of non-cash investing and financing activities:
Settlement of Convertible preferred stock liability in connection with the issuance of Series B convertible preferred stock		2,281,000
Conversion of convertible preferred stock to common stock upon initial public offering	162,612,000
Series B Preferred Stock [Member]
Cash flows from financing activities:
Proceeds from Issuance of Convertible Preferred Stock		25,858,000
Series C Preferred Stock [Member]
Cash flows from financing activities:
Proceeds from Issuance of Convertible Preferred Stock		$ 79,702,000
IPO
Cash flows from financing activities:
Proceeds from issuance of common stock	143,741,000
Private Placement
Cash flows from financing activities:
Proceeds from issuance of common stock	$ 20,000,000

Organization and Description of

Organization and Description of the Business	12 Months Ended
	Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Description of the Business	1. Organization and Description of the Business Description of the Business Imago BioSciences, Inc., or Imago, or the Company, was incorporated on March 28, 2012 as a Delaware corporation and is headquartered in South San Francisco, California. The Company is a clinical-stage biopharmaceutical company discovering and developing small molecule product candidates that target lysine-specific demethylase 1, or LSD1, an enzyme that plays a central role in the production of blood cells in the bone marrow. The Company is focused on improving the quality of life of patients with cancer and bone marrow diseases in addition to prolonging their lives. The Company’s lead product candidate is bomedemstat for the treatment of myeloproliferative neoplasms, or MPNs, a family of related, chronic cancers of the bone marrow. The three most common MPNs are myelofibrosis, or MF, essential thrombocythemia, or ET, and polycythemia vera or PV. The Company is pursuing the development of bomedemstat as a potentially disease-modifying therapy in ET and MF to address the limitations of currently approved therapies. The Company has completed enrollment in a Phase 2 clinical trial of bomedemstat for the treatment of MF and is currently enrolling patients in a Phase 2 clinical trial of bomedemstat for the treatment of ET. To enable the collection of long-term safety and pharmacodynamic data, Imago initiated a Phase 2 Extension Study in 2021 into which patients from our Phase 2 clinical trials in MF and ET will transition. Initial public offering On July 15, 2021, the Company’s registration statement on Form S-1 (File No. 333-257419), or the Prospectus, relating to its initial public offering, or the IPO, of common stock became effective. The IPO closed on July 20, 2021 at which time the Company issued an aggregate of 8,400,000 shares of its common stock at a price of $ 16.00 per share. Within 30 days following the close, 1,260,000 shares were issued in connection with the full exercise by the underwriters of their option to purchase additional shares of common stock. In connection with the completion of its IPO, on July 20, 2021 the Company’s certificate of incorporation was amended and restated to provide for 300,000,000 authorized shares of common stock with a par value of $ 0.0001 per share and 10,000,000 authorized shares of preferred stock with a par value of $ 0.0001 per share. The Company received net proceeds of approximately $ 140.5 million from the IPO, after deducting underwriting discounts, commissions and offering costs. Concurrent with the IPO, the Company issued 1,250,000 shares of common stock in a private placement, or the Private Placement, for net proceeds of $ 20.0 million. Immediately prior to the completion of the IPO, all shares of convertible preferred stock then outstanding were converted into 21,435,632 shares of common stock. Liquidity and capital resources The Company has incurred net losses and cash out flows from operations since inception and as of December 31, 2021 has an accumulated deficit of $ 112.7 million. As of December 31, 2021, the Company had cash, cash equivalents and short-term investments of $ 217.4 million, which are available to fund future operations. Management expects to incur additional losses in the future to conduct research and development and recognizes the need to raise capital to fully implement its business plan. The Company has historically financed its operations primarily with the proceeds from the issuance of its convertible preferred stock and to a lesser extent debt financing. The Company may raise additional capital through additional equity financings, debt financings or other sources. Based on projected activities, management believes that its existing cash, cash equivalents and short-term investments as of December 31, 2021 will be sufficient to support operations for at least the next 12 months following issuance of these consolidated financial statements. Reverse stock split On July 13, 2021, the Company effected a reverse stock split of the Company’s common stock on an 8.4 -for-1 basis, or the Reverse Stock Split. In connection with the Reverse Stock Split, all common stock and convertible preferred stock share and per share amounts for all periods presented in these consolidated financial statements have been retroactively adjusted, to reflect this Reverse Stock Split. Authorized shares and par values were not adjusted. Coronavirus pandemic On January 30, 2020, the World Health Organization, or WHO, announced a global health emergency because of a new strain of coronavirus originating in Wuhan, China, or the COVID-19 outbreak, and the risks to the international community as the virus spread globally beyond its point of origin. In March 2020, the WHO classified the COVID-19 outbreak as a pandemic, based on the rapid increase in exposure globally. The full impact of the COVID-19 pandemic continues to evolve as of the date of these consolidated financial statements. As such, it is uncertain as to the full magnitude that the pandemic will have on the Company’s financial condition, liquidity, and future results of operations. Management is actively monitoring the global situation for potential effects on the Company's financial condition, liquidity, operations, suppliers, industry, and workforce. Given the volatility and evolution of the continuing COVID-19 pandemic and the evolving global responses to curb rates of infection from new strains, such as Omicron, rates of hospitalization and death, and to enhance the global rates of full vaccination and availability of vaccine boosters and COVID-19 treatments, the Company is not able to estimate the effects of the COVID-19 pandemic on its results of operations, financial condition, or liquidity. Although the Company cannot estimate the length or gravity of the impact of the COVID-19 outbreak at this time, if the pandemic continues, it may have a material adverse effect on the Company’s results of future operations, financial position, and liquidity in 2022.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Basis of Presentation The consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles, or U.S. GAAP. The consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. All intercompany balances and transactions have been eliminated. Use of Estimates The preparation of consolidated financial statements in conformity with U.S. 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 consolidated financial statements and the reported amounts of expenses during the reporting period. Significant estimates and assumptions made in the accompanying consolidated financial statements include, but are not limited to, certain accrued liabilities for research and development activities, valuation of deferred tax assets, the fair values of common and convertible preferred stock, the fair value of stock options and the fair value of the convertible preferred stock tranche liability. The Company evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors and adjusts those estimates and assumptions when facts and circumstances dictate. Actual results could differ from those estimates. Segment Information The Company has one operating segment and one reportable segment, which is the business of discovering and developing small molecule product candidates that target LSD1, an enzyme that plays a central role in the production of blood cells in the bone marrow. The Company’s chief operating decision maker, its Chief Executive Officer, reviews financial information on an aggregate basis for the purpose of allocating resources and evaluating financial performance. Cash and Cash Equivalents The Company considers all highly liquid investments purchased with original maturities of three months or less from the purchase date to be cash equivalents. The Company’s cash equivalents include deposits in money market accounts which were unrestricted as to withdrawal or use and are stated at fair value. Investments All investments in debt securities have been classified as “available-for-sale” and are carried at estimated fair value as determined based upon quoted market prices or pricing models for similar securities. Management determines the appropriate classification of its investments in debt securities at the time of purchase and reevaluates such designation as of each balance sheet date. Short-term investments have maturities less than one year as of the consolidated balance sheet dates. Long-term investments have maturities greater than one year as of the consolidated balance sheet dates. Unrealized gains and losses are excluded from operations and are reported as a component of comprehensive loss. Realized gains and losses and declines in fair value judged to be other than temporary, if any, on investments in debt securities are included in other income (expense), net in the consolidated statements of operations. The cost of securities sold is based on the specific-identification method. Interest earned on investments in securities is included in interest income. Fair Value of Financial Instruments Financial 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 Company measures fair value based on a three-tier hierarchy, which prioritizes the inputs used in the valuation methodologies in measuring fair value as follows: Level 1—Observable inputs such as unadjusted quoted prices in active markets for identical assets or liabilities as of the measurement date. Level 2—Inputs (other than quoted prices included within Level 1) that are directly observable for the asset or liability or indirectly observable for similar assets or liabilities. Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to determining the fair value of the assets or liabilities. The Company’s cash and cash equivalents, prepaid expenses and other current assets, accounts payable and accrued and other current liabilities approximate their fair value due to their short maturities. Concentrations of Credit Risk Financial instruments that potentially subject the Company to significant concentrations of credit risk consist primarily of cash, cash equivalents and short-term investments. Cash, cash equivalents and short-term investments are invested through banks and other accredited financial institutions in the United States. Such deposits may be in excess of federally insured limits. Risk and Uncertainties The Company is subject to certain risks and uncertainties similar to other development-stage biopharmaceutical companies, including but not limited to: the Company’s ability to successfully develop, manufacture, and market its products; the Company’s ability to obtain regular clearance from U.S. Food and Drug Administration, or FDA or foreign regulatory agencies prior to commercial sales; new technological innovations; the Company’s dependence on key personnel; the Company’s ability to obtain, maintain and enforce intellectual property protection directed to its current and any future technologies that it develops; compliance with governmental regulations; uncertainty of market acceptance of products; product liability; and the Company’s need to obtain additional financing. Property and Equipment, Net Property and equipment, net is stated at cost, net of accumulated depreciation. Depreciation is computed using the straight-line method based on the estimated useful lives of the assets, which is generally three to five years . Maintenance and repairs are charged to expense as incurred. Significant improvements that substantially enhance the useful life of an asset are capitalized and depreciated. When assets are retired or disposed of, the cost together with related accumulated depreciation is removed from the consolidated balance sheets and any resulting gain or loss is reflected in the Company’s consolidated statements of operations in the period realized. Leases The Company determines if an arrangement is a lease at inception. Operating leases with a term of 12 months or more are recognized as operating lease right-of-use, or ROU, assets and lease liabilities are recognized as operating lease liabilities in the Company’s consolidated balance sheets. ROU assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent the Company’s obligation to make lease payments arising from the lease. Operating lease ROU assets and liabilities are recognized based on the present value of lease payments over the lease term at the commencement date of the lease. ROU assets also include any initial direct costs incurred and any lease payments made at or before the lease commencement date, less any lease incentive received. The Company uses its incremental borrowing rate based on the information available at the commencement date in determining the present value of lease payments. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Lease expense for lease payments is recognized on a straight-line basis over the lease term. The Company’s non-lease components are primarily related to property maintenance, which varies based on future outcomes, and is recognized as rent expense when incurred. Impairment for Long-Lived Assets Long-lived assets, such as property and equipment are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. If circumstances require a long-lived asset or asset group to be tested for possible impairment, the Company first compares undiscounted cash flows expected to be generated by that asset or asset group to its carrying value. If the carrying value of the long-lived asset or asset group is not recoverable on an undiscounted cash flow basis, an impairment is recognized to the extent that the carrying value exceeds its fair value. Fair value is determined through various valuation techniques including discounted cash flow models, quoted market values and third-party independent appraisals, as considered necessary. There were no such impairment losses for the years ended December 31, 2021 and 2020. Deferred Offering Costs Deferred offering costs, consisting of legal, accounting, audit and filing fees relating to an IPO, are capitalized. In July 2021, upon the closing of the IPO, all deferred offering costs which were included in other long-term assets in the accompanying consolidated balance sheets were offset against the Company’s IPO proceeds. Convertible Preferred Stock Tranche Liability In 2019, the Company completed the initial closings for the sale of its Series B convertible preferred stock. In accordance with the terms of the Series B convertible preferred stock financing, the Company was also committed to sell 4,529,931 shares of Series B convertible preferred stock at a fixed price per share of $ 5.712 in a second closing on or after March 1, 2020. The Company’s obligation to issue additional shares of its Series B convertible preferred stock at a fixed price in a future closing represents a freestanding financial instrument that is accounted for as a liability. The liability is measured at fair value from the original issuance date of its Series B convertible preferred stock in March 2019 and is subject to remeasurement at each reporting period with changes in fair value recognized in the consolidated statements of operations until settlement or extinguishment. The convertible preferred stock tranche liability was settled on the closing of the Company’s Series B convertible preferred stock financing in July 2020. Immediately prior to the IPO, all outstanding shares of our convertible preferred stock were converted into shares of our common stock. Research and Development Expenses Research and development costs are expensed as incurred. Research and development costs consist of salaries, benefits, and other personnel related costs, including stock-based compensation, laboratory supplies, clinical studies and related clinical manufacturing costs, fees paid to other entities to conduct certain research and development activities on the Company’s behalf, as well as allocated facility and other related costs. Non-refundable advance payments for goods or services that will be used or rendered for future research and development activities are deferred and capitalized as prepaid expenses until the related goods are delivered or services are performed. The Company estimates preclinical and clinical study research expenses based on the services performed, pursuant to contracts with research institutions and clinical research organizations that conduct and manage preclinical and clinical studies and research services on its behalf. The Company records the costs of research and development activities based upon the estimated amount of services provided but not yet invoiced and includes these costs in accrued and other current liabilities in the consolidated balance sheets. These costs are a component of the Company’s research and development expenses. The Company accrues for these costs based on factors such as estimates of the work completed and in accordance with agreements established with its third-party service providers under the service agreements. The Company makes significant judgments and estimates in determining the accrued and other current liabilities balance. As actual costs become known, the Company adjusts its accrued expenses. The Company has not experienced any material differences between accrued costs and actual costs incurred. However, the status and timing of actual services performed may vary from the Company’s estimates, resulting in adjustments to expense in future periods. Changes in these estimates that result in material changes to the Company’s accrued costs could materially affect the Company’s results of operations. Stock-Based Compensation Stock-based compensation is measured at the grant date for all equity awards granted to employees and non-employees based on the fair value of the awards, including stock options and restricted shares. The Company estimates the fair value of stock-based awards on the date of grant using the Black-Scholes option-pricing model. For stock-based awards that vest subject to the satisfaction of a service requirement, the expense is recognized using the straight-line method over the requisite service period, which is generally the vesting period. Forfeitures are accounted for when they occur. Income Taxes Income taxes are accounted for using the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts or existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using the enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period of enactment. The Company records a valuation allowance to reduce deferred tax assets to an amount expected to be realized. The Company recognizes the tax benefit from an uncertain tax position if it is more likely than not that the tax position will be sustained upon examination by the tax authorities, based on the merits of the position. The Company’s policy is to recognize interest and penalties related to the underpayment of income taxes as a component of its provision for income taxes. To date, there have been no interest or penalties charged in relation to the unrecognized tax benefits. Net Loss Per Share Basic net loss per share is calculated by dividing the net loss by the weighted-average number of shares of the Company’s common stock outstanding for the period, without consideration for potential dilutive shares of common stock. As the Company is in a loss position for the periods presented, diluted net loss per share is the same as basic net loss per share, since the effects of potentially dilutive securities are antidilutive. Comprehensive Loss Comprehensive loss includes net loss and certain changes in stockholders’ equity (deficit) that are excluded from net loss. The Company’s comprehensive loss is comprised of unrealized gains and losses on the Company’s available-for-sale investments. Emerging Growth Company Status The Company is an emerging growth company, as defined in the Jumpstart Our Business Startups Act of 2012, or JOBS Act. Under the JOBS Act, emerging growth companies can delay adopting new or revised accounting standards issued subsequent to the enactment of the JOBS Act until such time as those standards apply to private companies. The Company has elected to use this extended transition period for complying with new or revised accounting standards that have different effective dates for public and private companies until the earlier of the date that it is (a) no longer an emerging growth company or (b) affirmatively and irrevocably opt out of the extended transition period provided in the JOBS Act. As a result, these consolidated financial statements may not be comparable to companies that comply with the new or revised accounting pronouncements as of public company effective dates. Recently Adopted Accounting Pronouncements In August 2018, the Financial Accounting Standards Board, or FASB issued Accounting Standards Update, or ASU, 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 (a consensus of the FASB Emerging Issues Task Force), or ASU 2018-15. The ASU clarified that implementation, setup and other upfront costs related to cloud computing agreements, or CCA, should be accounted for under ASC 350-40. ASU 2018-15 requires companies to capitalize certain costs incurred when purchasing a CCA that is a service. Under the new guidance, companies should apply the same criteria for capitalizing implementation costs in a CCA service as they would for internal-use software. The capitalized implementation costs should be generally expensed over the term of the service agreement and the related assets should be assessed for impairment using the same model applied to long-lived assets. As an emerging growth company, this new standard is effective for annual periods beginning after December 15, 2020. T he Company adopted this standard prospectively on January 1, 2021 . The adoption did no t have a material impact on the Company’s consolidated financial statements. Recently Issued Accounting Pronouncements Not Yet Adopted In June 2016, the FASB issued ASU 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments , which replaces the existing incurred loss impairment model with an expected credit loss model and requires a financial asset measured at amortized cost to be presented at the net amount expected to be collected. As an emerging growth company, this new standard is effective for the Company in the fiscal year beginning January 1, 2023 and must be adopted using a modified retrospective approach, with certain exceptions. The Company is currently evaluating the impact of this standard on its consolidated financial statements and related disclosures. In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes , or ASU 2019-12, which is intended to simplify the accounting for income taxes. The guidance eliminates certain exceptions to the approach for intra period tax allocation, the methodology for calculating income taxes in an interim period and the recognition of deferred tax liabilities for outside basis differences. As an emerging growth company, this new standard is effective for the Company for fiscal year beginning January 1, 2022. The Company does not expect this standard to have a material impact on its consolidated financial statements and related disclosures.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2021
Fair Value Disclosures [Abstract]
Fair Value Measurements	3. Fair Value Measurements The Company utilizes valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs to the extent possible. The Company determines fair value based on assumptions that market participants would use in pricing an asset or liability in the principal or most advantageous market. When considering market participant assumptions in fair value measurements, the following fair value hierarchy distinguishes between observable and unobservable inputs, which are categorized in one of the following levels: ▪ Level 1 Inputs: Unadjusted quoted prices in active markets for identical assets or liabilities accessible to the reporting entity at the measurement date. ▪ Level 2 Inputs: Other than quoted prices included in Level 1 inputs that are observable for the asset or liability, either directly or indirectly, for substantially the full term of the asset or liability. ▪ Level 3 Inputs: Unobservable inputs for the asset or liability used to measure fair value to the extent that observable inputs are not available, thereby allowing for situations in which there is little, if any, market activity for the asset or liability at measurement date. Fair value accounting is applied for all financial assets and liabilities that are recognized or disclosed at fair value in the financial statements on a recurring basis (at least annually). As of December 31, 2021 and 2020, the carrying amount of prepaid expenses and other current assets, accounts payable and accrued liabilities approximated their estimate fair value due to their relatively short maturities. The following tables present information about the Company’s financial assets and liabilities measured at fair value on a recurring basis and indicates the level of the fair value hierarchy utilized to determine such fair values: December 31, 2021 Level 1 Level 2 Level 3 Fair Value (in thousands) Assets: Money market funds $ 7,794 $ — $ — $ 7,794 Corporate bonds — 4,499 — 4,499 Commercial paper — 187,749 — 187,749 U.S. treasury securities — 16,024 — 16,024 Total financial assets $ 7,794 $ 208,272 $ — $ 216,066 December 31, 2020 Level 1 Level 2 Level 3 Fair Value (in thousands) Assets: Money market funds $ 11,938 $ — $ — $ 11,938 Corporate bonds — 5,671 — 5,671 Commercial paper — 57,195 — 57,195 U.S. treasury securities — 20,196 — 20,196 Total financial assets $ 11,938 $ 83,062 $ — $ 95,000 Money market funds are highly liquid investments and are actively traded. The pricing information on the Company’s money market funds is readily available and can be independently validated as of the measurement date. This approach results in the classification of these securities as Level 1 of the fair value hierarchy. The Company’s short-term investments are classified as cash equivalents if their original maturities are less than three months. The Company’s short-term investments are considered Level 2 financial instruments as their fair values are determined using inputs that are observable in the market or can be derived principally from recently executed transactions, cash flow models with yield curves, and benchmark securities. There were no transfers in or out of Level 3 of the fair value hierarchy during the periods presented. Convertible Preferred Stock Tranche Liability The Company’s convertible preferred stock tranche liability was determined based on significant inputs not observable in the market, which represents a Level 3 measurement within the fair value hierarchy. In determining the fair value of the convertible preferred stock tranche liability, the Company used the Hybrid Tranche Model pricing model to estimate the fair value using unobservable inputs. On the closing of the Company’s Series B convertible preferred stock financing in July 2020, the convertible preferred stock tranche liability was settled and recorded to Series B convertible preferred stock. Accordingly, there is no convertible preferred stock tranche liability as of December 31, 2021 and 2020. A summary of the significant unobservable inputs used in measuring the Company’s convertible preferred stock tranche liability as of July 2, 2020 was as follows: July 2, 2020 Time to liquidity (years) 0.01 Probability of second closing 100 % Discount rate 20 % The following table provides a summary of changes in the estimated fair value of the Company’s convertible preferred stock tranche liability measured on a recurring basis using significant Level 3 inputs: Year Ended 2020 (in thousands) Beginning balance January 1, 2020 $ 2,495 Change in fair value $ ( 214 ) Settlement of convertible preferred stock tranche liability ( 2,281 ) Ending balance December 31, 2020 $ —

Investments

Investments	12 Months Ended
	Dec. 31, 2021
Investments, Debt and Equity Securities [Abstract]
Investments	4. Investments The following tables summarize the fair value and amortized cost of the Company’s available-for-sale debt securities by major security type: December 31, 2021 Amortized Gross Gross Aggregate (in thousands) Assets: Money market funds $ 7,794 $ — $ — $ 7,794 Corporate bonds 4,500 — ( 1 ) 4,499 Commercial paper 187,789 17 ( 57 ) 187,749 U.S. treasury securities 16,026 — ( 2 ) 16,024 Total financial assets $ 216,109 $ 17 $ ( 60 ) $ 216,066 December 31, 2020 Amortized Gross Gross Aggregate (in thousands) Assets: Money market funds $ 11,938 $ — $ — $ 11,938 Corporate bonds 5,672 1 ( 2 ) 5,671 Commercial paper 57,197 3 ( 5 ) 57,195 U.S. treasury securities 20,196 2 ( 2 ) 20,196 Total financial assets $ 95,003 $ 6 $ ( 9 ) $ 95,000 The following table summarizes the classification of the Company’s available-for-sale debt securities on the consolidated balance sheets: December 31, 2021 2020 (in thousands) Cash equivalents $ 9,882 $ 17,936 Short-term investments 206,184 57,375 Long-term investments — 19,689 Total cash equivalents and investments $ 216,066 $ 95,000 The following table summarizes the fair values of the Company’s available-for-sale debt securities by contractual maturity: December 31, 2021 2020 (in thousands) Within one year $ 216,066 $ 75,311 After one year through two years — 19,689 Total cash equivalents and investments $ 216,066 $ 95,000 There were no impairments of available-for-sale debt securities considered “other-than-temporary” during the year ended December 31, 2021 as it was more likely than not the Company would hold the securities until maturity or a recovery of the cost basis.

Balance Sheet Components

Balance Sheet Components	12 Months Ended
	Dec. 31, 2021
Payables and Accruals [Abstract]
Balance Sheet Components	5. Balance Sheet Components Accrued and Other Current Liabilities Accrued and other current liabilities consist of the following: December 31, 2021 2020 (in thousands) Accrued research and development $ 4,213 $ 2,670 Compensation and related benefits 1,881 854 Accrued professional service expenses 207 — Other 332 202 Total accrued and other current liabilities $ 6,633 $ 3,726

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	6. Commitments and Contingencies Operating Leases As of December 31, 2021 and 2020, the Company has cancellable operating lease agreements with lease terms of less than 12 months. For both years ended December 31, 2021 and 2020, rent expense was $ 0.1 million. Guarantees and Indemnifications In the normal course of business, the Company enters into agreements that contain a variety of representations and provide for general indemnifications. The Company’s exposure under these agreements is unknown because it involves claims that may be made against the Company in the future. To date, the Company has not paid any claims or been required to defend any action related to its indemnification obligations. As of December 31, 2021 and 2020, the Company does not have any material indemnification claims that were probable or reasonably possible and, consequently, has not recorded related liabilities.

Equity

Equity	12 Months Ended
	Dec. 31, 2021
Equity [Abstract]
Equity	7. Equity Convertible Preferred Stock Convertible preferred stock at December 31, 2020 consisted of the following: Shares Shares Issued and Outstanding Net Carrying Value Liquidation (in thousands, except shares) Convertible Preferred Stock Series A 47,647,051 5,672,256 $ 38,015 $ 40,500 Series B 66,176,463 7,878,135 44,895 45,000 Series C 66,236,125 7,885,241 79,702 80,000 Total 180,059,639 21,435,632 $ 162,612 $ 165,500 The Company classifies its convertible preferred stock outside of total stockholders’ equity (deficit) because, in the event of certain “liquidation events” that are not solely within the control of the Company (including a merger, acquisition or sale of all or substantially all of the Company’s assets), the shares would become redeemable at the option of the holders. The Company did not adjust the carrying values of the convertible preferred stock to the deemed liquidation values of such shares since a liquidation event as of December 31, 2020 was not probable of occurring. Upon completion of the Company’s IPO in July 2021, all outstanding shares of convertible preferred stock were converted into 21,435,632 shares of common stock. Common Stock The holders of the Company’s common stock have one vote for each share of common stock. Common stockholders are entitled to dividends when, as, and if declared by the board of directors, subject to the prior rights of any preferred stockholders outstanding. The holders have no preemptive or other subscription rights and there is no redemption or sinking fund provisions with respect to such shares. As of December 31, 2021, no such dividends were declared or accrued. The Company reserved the following shares of common stock, on an as-if converted basis, for issuance as follows: December 31, 2021 2020 Conversion of outstanding shares of convertible preferred stock — 21,435,632 Options outstanding under the 2021 Equity Incentive plan 4,028,461 1,729,843 Options available for future grant 2,673,582 1,678,228 Reserved for employee stock purchase plan 350,000 — Total 7,052,043 24,843,703

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2021
Share-based Payment Arrangement [Abstract]
Stock-Based Compensation	8. Stock-Based Compensation 2012 Equity Incentive Plan In October 2012, the Company adopted the 2012 Equity Incentive Plan (the “2012 Plan”) under which 238,095 shares of the Company’s common stock were initially reserved for issuance to employees, directors and consultants. 2021 Equity Incentive Plan In July 2021, the Company adopted the 2021 Incentive Award Plan, (the “2021 Plan”) which became effective in connection with the IPO. As a result of the 2021 Plan, the Company may not grant any additional awards under the 2012 Plan. The 2012 Plan will continue to govern outstanding equity awards granted thereunder. Under the terms of the 2021 Plan, the Company may grant stock options, stock appreciation rights, restricted stock awards, restricted stock unit awards, performance bonus awards, performance stock unit awards, dividend equivalents awards or other stock or cash based awards to individuals who are then employees, consultants or directors of the Company. Under the terms of the 2021 Plan, options may be granted at an exercise price not less than fair market value. For employees holding more than 10 % of the voting rights of all classes of stock, the exercise prices for incentive and non-statutory stock options may not be less than 110 % of fair market value, as determined by the Board of Directors. The terms of options granted under the 2021 Plan may not exceed ten years . The vesting schedule of newly issued option grants is generally four years . The Company initially reserved 3,450,000 shares of common stock for issuance under the 2021 Plan. The number of shares initially reserved will be increased by (i) any shares available for issuance under the 2012 Plan as of the day before the IPO, (ii) any shares that are subject to the 2012 Plan that become available for issuance under the 2012 Plan and (iii) the annual increase on January 1 of each year, beginning January 1, 2022 , and continuing through and including January 1, 2031 , by 5 % of the shares of common stock outstanding on the last day of the immediately preceding fiscal year, or a lesser number of shares determined by the Company's board of directors. As of December 31, 2021, there were 2,673,582 shares authorized for issuance under the 2021 Plan. 2021 Employee Stock Purchase Plan In July 2021, the Company adopted the Employee Stock Purchase Plan, (the “ESPP”), which became effective in connection with the IPO. The purpose of the ESPP is to assist employees of the Company in acquiring a stock ownership interest in the Company, and to help such employees provide for their future security and to encourage them to remain in the employment of the Company. The ESPP is intended to qualify as an “employee stock purchase plan” within the meaning of Section 423 of the Code. The compensation committee of the board of directors will administer the Company’s ESPP. The maximum aggregate number of shares of common stock that may be issued pursuant to the exercise of purchase rights under the Company’s ESPP that are granted to employees is 4,703,469 shares. Additionally, the number of shares of common stock reserved for issuance under the Company’s ESPP will increase automatically each year, beginning on January 1, 2022 , and continuing through and including January 1, 2031 , by 1 % of the total number of shares of common stock outstanding on December 31 of the preceding calendar year, or a lesser number as determined by the board of directors. Shares subject to purchase rights granted under the Company’s ESPP that terminate without having been exercised in full will be added back the number of shares available for issuance under the Company’s ESPP. As of December 31, 2021, 350,000 shares were available for future purchase. There were no shares issued under the ESPP during the year ended December 31, 2021. Stock Option Activity Stock option activity under the 2012 and 2021 Plan was as follows: Options Available for Grant Number of Options Outstanding Weighted-Average Exercise Price Per Share Weighted-Average Aggregate Intrinsic Value (in thousands) Outstanding as of January 1, 2021 1,678,228 1,729,843 $ 2.08 7.75 $ 3,666 Authorized 3,450,000 — — Share rounding difference as a result of the 60 — — Options granted ( 2,867,965 ) 2,867,965 11.76 Options exercised — ( 156,088 ) 3.24 Options cancelled 413,259 ( 413,259 ) 3.18 Outstanding as of December 31, 2021 2,673,582 4,028,461 $ 8.81 8.40 $ 60,089 Exercisable as of December 31, 2021 1,326,075 $ 2.73 6.52 $ 27,826 The aggregate intrinsic values of options outstanding and exercisable were calculated as the difference between the exercise price of the options and the closing price of the Company’s common stock of $ 23.71 as of December 31, 2021. The total intrinsic value of options exercised during the year ended December 31, 2021 was $ 2.0 million. The total intrinsic value of options exercised during the year ended December 31, 2020 was immaterial. The intrinsic value is the difference between the fair value of Company’s common stock at the time of exercise and the exercise price of the stock option. The weighted-average grant-date fair value per share for stock options granted during the years ended December 31, 2021 and 2020 was $ 7.15 and $ 1.20 , respectively. Determining Fair Value The estimated grant-date fair value of the Company’s stock-based awards was calculated using the Black-Scholes option pricing model, based on the following assumptions: Year Ended, 2021 2020 Expected term (in years) 5.8 - 6.1 3.2 - 6.1 Expected volatility 65.2 % - 69.9 % 67.1 % - 95.4 % Risk-free interest rate 0.6 % - 1.5 % 0.36 % - 2.56 % Expected dividend yield —% —% Each of these inputs is subjective and generally requires significant judgment. Expected Term —The expected term represents the period that the Company’s stock-based awards are expected to be outstanding and is determined using the simplified method, which is based on the mid-point between the contractual term and vesting period. Volatility —The Company determines volatility based on the historical volatilities of comparable publicly traded life science companies over a period equal to the expected term because it does not have sufficient trading history for its common stock price. The comparable companies were chosen based on the similar size, stage in the life cycle, or area of specialty. The Company will continue to apply this process until a sufficient amount of historical information regarding volatility on its own stock becomes available. Risk-Free Interest Rate —The risk-free interest rate is determined by reference to the U.S. Treasury yield curve in effect at the time of grant of the award for time periods approximately equal to the expected term of the award. Dividend Yield —The Company has never paid and has no plans to pay any dividends on its common stock. Therefore, the Company has used an expected dividend yield of zero . Stock-Based Compensation Total stock-based compensation recognized in the consolidated statements of operations is as follows: Year Ended, 2021 2020 Research and development $ 784 $ 283 General and administrative 1,441 143 Total stock-based compensation expense $ 2,225 $ 426 As of December 31, 2021, total unrecognized stock-based compensation expense is approximately $ 18.7 million, related to unvested stock options to be recognized over the remaining weighted-average vesting period of 3.2 years.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Income Taxes	9. Income Taxes For the years ended December 31, 2021 and 2020, the Company recorded income tax expense of $ 2,000 and $ 3,000 , respectively. The Company has incurred net operating losses for all periods presented. The Company has not reflected any benefit of such net operating loss carryforwards in the accompanying consolidated financial statements. The U.S. federal and state deferred tax assets generated from the Company have been fully reserved, as the Company believes it is not more likely than not that the benefit will be realized. The effective tax rate of the provision for income taxes differs from the federal statutory rate as follows: Year Ended December 31, 2021 2020 U.S. federal taxes at statutory rate 21.0 % 21.0 % State taxes (net of federal benefit) 0.8 2.3 Non-deductible expenses ( 0.2 ) ( 0.3 ) Credits 8.1 11.9 Change in valuation allowance ( 13.1 ) ( 34.9 ) Derecognition due to Section 383 Limitations ( 16.7 ) — Other 0.1 — Effective tax rate —% — % Deferred Tax Assets The tax effects of temporary differences and carryforwards that give rise to significant portions of deferred tax assets are as follows: December 31, 2021 2020 (in thousands) Deferred tax assets: Net operating loss carryforwards $ 24,827 $ 16,007 Tax credits carryforwards 3,997 7,661 Capitalized start-up costs 546 644 Accrued expenses 436 198 Stock-based compensation 316 64 Other 5 1 Total gross deferred tax assets 30,127 24,575 Less: valuation allowance ( 30,127 ) ( 24,575 ) Total deferred tax assets, net $ — $ — The realization of deferred tax assets is dependent upon future earnings, if any, the timing and amount of which are uncertain. The Company has established a valuation allowance to offset deferred tax assets as of December 31, 2021 and 2020 due to the uncertainty of realizing future tax benefits from its net operating loss carryforwards and other deferred tax assets. Accordingly, the deferred tax assets have been fully offset by a valuation allowance. The changes in the valuation allowance for the years ended December 31, 2021 and 2020 were $ 5.6 million and $ 6.2 million, respectively. Net Operating Loss and Tax Credit Carryforwards The Company has federal net operating loss carryforwards, or NOLs, of $ 106.9 million as of December 31, 2021 which will begin to expire in 2033 except for $ 76.9 million of the NOLs that can be carried forward indefinitely . As a result of the U.S. Tax Cuts and Jobs Act, for U.S. income tax purposes, federal NOLs generated in tax years beginning before January 1, 2018 can still be carried forward for up to 20 years , but NOLs generated for tax years beginning after December 31, 2017 can be carryforward indefinitely and are limited to 80 % utilization against taxable income. As of December 31, 2021, the Company has state NOLs for California of $ 0.4 million, Massachusetts of $ 34.1 million, and New Hampshire of $ 2.7 million. The state NOLs, if not utilized, will expire beginning in 2033 and 2034 . If the Company experiences a greater than 50 percentage point aggregate change in ownership over a three-year period (a Section 382 ownership change), utilization of its pre-change NOL carryforwards are subject to annual limitation under Section 382 of the Internal Revenue Code, or IRC. The annual limitation is deemed by multiplying the value of the Company’s stock at the time of such ownership change by the applicable long-term tax-exempt rate. Such limitations may result in expiration of a portion of the NOL carryforwards before utilization. As of December 31, 2020, the Company determined that ownership changes occurred on October 30, 2014 and November 12, 2020. As a result of the ownership changes, none of the NOLs will expire unutilized for federal, California and Massachusetts purposes, respectively. During the year ended December 31, 2021, the Company completed an analysis and determined that no ownership change occurred under Section 382. Therefore, no derecognized NOL related deferred tax assets in the tax effected amounts for federal and California purposes, respectively. The ability of the Company to use its remaining NOL carryforwards may be further limited if the Company experiences a Section 382 ownership change as a result of future changes in its stock ownership. As of December 31, 2021, Company has federal research and development, or R&D, credit carryforwards of approximately $ 0.1 million which will begin to expire in 2040 for federal tax purposes. As of December 31, 2021, the Company has California R&D credit carryforwards of approximately $ 0.4 million which can be carried forward indefinitely and Massachusetts R&D credit carryforwards of approximately $ 0.2 million which will expire in 2032 . Research and development credits are subject to IRC Section 383. In the event of a change in ownership as defined by this code section, the usage of the credits may be limited. As a result of the previously mentioned ownership changes, the Company has derecognized approximately $ 0.5 million of the gross federal research and development credit-related deferred tax assets due to the Section 383 limitation as of December 31, 2021. The Company has no t derecognized any of the California or Massachusetts research and development credit-related deferred tax assets because the credits do not expire. As of December 31, 2021, the Company has federal orphan drug credit carryforwards of approximately $ 4.8 million available to reduce future taxable income, if any, which will begin to expire in 2037 for federal tax purposes. Research and development credits are subject to IRC Section 383. In the event of a change in ownership as defined by this code section, the usage of the credits may be limited. As a result of the previously mentioned ownership changes, the Company has derecognized $ 8.4 million of the gross federal research and development credit-related deferred tax assets due to the Section 383 limitation as of December 31, 2021. Unrecognized Tax Benefits The Company has unrecognized tax benefits of $ 1.4 million and $ 2.1 million as of December 31, 2021 and 2020, which would affect the effective tax rate if recognized; however, recognition would be in the form of a deferred tax attribute which would be offset by a valuation allowance with no impact to tax expense. The Company does not anticipate any significant changes to unrecognized tax benefits over the next 12 months. The Company has recognized no interest or penalties related to uncertain tax positions for the periods presented. A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows: December 31, 2021 2020 (in thousands) Unrecognized tax benefits, beginning of period $ 2,104 $ 1,391 Gross increases related to prior tax positions 2 23 Gross decreases related to prior tax positions ( 1,894 ) — Lapse of statute of limitations — ( 17 ) Gross increases related to current tax positions 1,174 707 Unrecognized tax benefits, end of period $ 1,386 $ 2,104 The Company files income tax returns in the United States, Alabama, California, Massachusetts, New Hampshire, New Jersey, New York and Texas. The Company is not currently under examination by income tax authorities in federal state or other jurisdictions. All tax returns remain open for examination by the federal and state authorities for three and four years , respectively, from the date of utilization of any NOLs or credits. Other Income Tax Related On March 27, 2020, the Coronavirus Aid, Relief and Economic Security Act, or the CARES Act, or the Act, was signed into law. The Act includes provisions relating to refundable payroll tax credits, deferment of the employer portion of certain payroll taxes, net operating loss carryback periods, alternative minimum tax credit refunds, and modifications to the net interest deduction limitations and technical corrections to tax depreciation methods for qualified improvement property. The company has evaluated the current legislation and at this time, does not anticipate the Act to have a material impact on its consolidated financial statements. On June 29, 2020, the California Governor signed Assembly Bill 85 or A.B. 85, which now becomes California law. A.B. 85, which includes several tax measures, provides for a three-year suspension of the use of net operating losses for medium and large businesses and a three-year cap on the use of business incentive tax credits to offset no more than $ 5.0 million of tax per year. Generally, A.B. 85 suspends the use of net operating losses for taxable years 2020, 2021, and 2022 for taxpayers with taxable income of $ 1.0 million or more. Since the Company is not expected to generate California source taxable income of more than $ 1.0 million, no material impact is anticipated at this time. On December 27, 2020, the Consolidated Appropriations Act, 2021, or the CAA, was signed into law. The CAA includes provisions meant to clarify and modify certain items put forth in the CARES Act, while providing aid to businesses affected by the pandemic. The CAA allows deductions for expenses paid for by the Paycheck Protection Program, or PPP, and Economic Injury Disaster Loan Program, or EIDL, clarifies forgiveness of EIDL advances, and other business pr ovisions. The Company analyzed the provisions of the CAA and determined there was no significant impact to its 2021 tax provision.

Net Loss Per Share

Net Loss Per Share	12 Months Ended
	Dec. 31, 2021
Earnings Per Share [Abstract]
Net Loss Per Share	10. Net Loss Per Share The following potentially dilutive shares, including all outstanding stock options, were not included in the calculation of diluted shares outstanding for the period presented as the effect would have been anti-dilutive: Year Ended, 2021 2020 Convertible preferred stock — 21,435,632 Outstanding stock options 4,028,461 1,729,843 Total 4,028,461 23,165,475

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2021
Subsequent Events [Abstract]
Subsequent Events	11. Subsequent Events None.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles, or U.S. GAAP. The consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. All intercompany balances and transactions have been eliminated.
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with U.S. 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 consolidated financial statements and the reported amounts of expenses during the reporting period. Significant estimates and assumptions made in the accompanying consolidated financial statements include, but are not limited to, certain accrued liabilities for research and development activities, valuation of deferred tax assets, the fair values of common and convertible preferred stock, the fair value of stock options and the fair value of the convertible preferred stock tranche liability. The Company evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors and adjusts those estimates and assumptions when facts and circumstances dictate. Actual results could differ from those estimates.
Segment Information	Segment Information The Company has one operating segment and one reportable segment, which is the business of discovering and developing small molecule product candidates that target LSD1, an enzyme that plays a central role in the production of blood cells in the bone marrow. The Company’s chief operating decision maker, its Chief Executive Officer, reviews financial information on an aggregate basis for the purpose of allocating resources and evaluating financial performance.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid investments purchased with original maturities of three months or less from the purchase date to be cash equivalents. The Company’s cash equivalents include deposits in money market accounts which were unrestricted as to withdrawal or use and are stated at fair value.
Investments	Investments All investments in debt securities have been classified as “available-for-sale” and are carried at estimated fair value as determined based upon quoted market prices or pricing models for similar securities. Management determines the appropriate classification of its investments in debt securities at the time of purchase and reevaluates such designation as of each balance sheet date. Short-term investments have maturities less than one year as of the consolidated balance sheet dates. Long-term investments have maturities greater than one year as of the consolidated balance sheet dates. Unrealized gains and losses are excluded from operations and are reported as a component of comprehensive loss. Realized gains and losses and declines in fair value judged to be other than temporary, if any, on investments in debt securities are included in other income (expense), net in the consolidated statements of operations. The cost of securities sold is based on the specific-identification method. Interest earned on investments in securities is included in interest income.
Fair Value of Financial Instruments	Fair Value of Financial Instruments Financial 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 Company measures fair value based on a three-tier hierarchy, which prioritizes the inputs used in the valuation methodologies in measuring fair value as follows: Level 1—Observable inputs such as unadjusted quoted prices in active markets for identical assets or liabilities as of the measurement date. Level 2—Inputs (other than quoted prices included within Level 1) that are directly observable for the asset or liability or indirectly observable for similar assets or liabilities. Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to determining the fair value of the assets or liabilities. The Company’s cash and cash equivalents, prepaid expenses and other current assets, accounts payable and accrued and other current liabilities approximate their fair value due to their short maturities.
Concentrations of Credit Risk	Concentrations of Credit Risk Financial instruments that potentially subject the Company to significant concentrations of credit risk consist primarily of cash, cash equivalents and short-term investments. Cash, cash equivalents and short-term investments are invested through banks and other accredited financial institutions in the United States. Such deposits may be in excess of federally insured limits.
Risk and Uncertainties	Risk and Uncertainties The Company is subject to certain risks and uncertainties similar to other development-stage biopharmaceutical companies, including but not limited to: the Company’s ability to successfully develop, manufacture, and market its products; the Company’s ability to obtain regular clearance from U.S. Food and Drug Administration, or FDA or foreign regulatory agencies prior to commercial sales; new technological innovations; the Company’s dependence on key personnel; the Company’s ability to obtain, maintain and enforce intellectual property protection directed to its current and any future technologies that it develops; compliance with governmental regulations; uncertainty of market acceptance of products; product liability; and the Company’s need to obtain additional financing.
Property and Equipment, Net	Property and Equipment, Net Property and equipment, net is stated at cost, net of accumulated depreciation. Depreciation is computed using the straight-line method based on the estimated useful lives of the assets, which is generally three to five years . Maintenance and repairs are charged to expense as incurred. Significant improvements that substantially enhance the useful life of an asset are capitalized and depreciated. When assets are retired or disposed of, the cost together with related accumulated depreciation is removed from the consolidated balance sheets and any resulting gain or loss is reflected in the Company’s consolidated statements of operations in the period realized.
Leases	Leases The Company determines if an arrangement is a lease at inception. Operating leases with a term of 12 months or more are recognized as operating lease right-of-use, or ROU, assets and lease liabilities are recognized as operating lease liabilities in the Company’s consolidated balance sheets. ROU assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent the Company’s obligation to make lease payments arising from the lease. Operating lease ROU assets and liabilities are recognized based on the present value of lease payments over the lease term at the commencement date of the lease. ROU assets also include any initial direct costs incurred and any lease payments made at or before the lease commencement date, less any lease incentive received. The Company uses its incremental borrowing rate based on the information available at the commencement date in determining the present value of lease payments. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Lease expense for lease payments is recognized on a straight-line basis over the lease term. The Company’s non-lease components are primarily related to property maintenance, which varies based on future outcomes, and is recognized as rent expense when incurred.
Impairment for Long-Lived Assets	Impairment for Long-Lived Assets Long-lived assets, such as property and equipment are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. If circumstances require a long-lived asset or asset group to be tested for possible impairment, the Company first compares undiscounted cash flows expected to be generated by that asset or asset group to its carrying value. If the carrying value of the long-lived asset or asset group is not recoverable on an undiscounted cash flow basis, an impairment is recognized to the extent that the carrying value exceeds its fair value. Fair value is determined through various valuation techniques including discounted cash flow models, quoted market values and third-party independent appraisals, as considered necessary. There were no such impairment losses for the years ended December 31, 2021 and 2020.
Deferred Offering Costs	Deferred Offering Costs Deferred offering costs, consisting of legal, accounting, audit and filing fees relating to an IPO, are capitalized. In July 2021, upon the closing of the IPO, all deferred offering costs which were included in other long-term assets in the accompanying consolidated balance sheets were offset against the Company’s IPO proceeds.
Convertible Preferred Stock Tranche Liability	Convertible Preferred Stock Tranche Liability In 2019, the Company completed the initial closings for the sale of its Series B convertible preferred stock. In accordance with the terms of the Series B convertible preferred stock financing, the Company was also committed to sell 4,529,931 shares of Series B convertible preferred stock at a fixed price per share of $ 5.712 in a second closing on or after March 1, 2020. The Company’s obligation to issue additional shares of its Series B convertible preferred stock at a fixed price in a future closing represents a freestanding financial instrument that is accounted for as a liability. The liability is measured at fair value from the original issuance date of its Series B convertible preferred stock in March 2019 and is subject to remeasurement at each reporting period with changes in fair value recognized in the consolidated statements of operations until settlement or extinguishment. The convertible preferred stock tranche liability was settled on the closing of the Company’s Series B convertible preferred stock financing in July 2020. Immediately prior to the IPO, all outstanding shares of our convertible preferred stock were converted into shares of our common stock.
Research and Development Expenses	Research and Development Expenses Research and development costs are expensed as incurred. Research and development costs consist of salaries, benefits, and other personnel related costs, including stock-based compensation, laboratory supplies, clinical studies and related clinical manufacturing costs, fees paid to other entities to conduct certain research and development activities on the Company’s behalf, as well as allocated facility and other related costs. Non-refundable advance payments for goods or services that will be used or rendered for future research and development activities are deferred and capitalized as prepaid expenses until the related goods are delivered or services are performed. The Company estimates preclinical and clinical study research expenses based on the services performed, pursuant to contracts with research institutions and clinical research organizations that conduct and manage preclinical and clinical studies and research services on its behalf. The Company records the costs of research and development activities based upon the estimated amount of services provided but not yet invoiced and includes these costs in accrued and other current liabilities in the consolidated balance sheets. These costs are a component of the Company’s research and development expenses. The Company accrues for these costs based on factors such as estimates of the work completed and in accordance with agreements established with its third-party service providers under the service agreements. The Company makes significant judgments and estimates in determining the accrued and other current liabilities balance. As actual costs become known, the Company adjusts its accrued expenses. The Company has not experienced any material differences between accrued costs and actual costs incurred. However, the status and timing of actual services performed may vary from the Company’s estimates, resulting in adjustments to expense in future periods. Changes in these estimates that result in material changes to the Company’s accrued costs could materially affect the Company’s results of operations.
Stock-Based Compensation	Stock-Based Compensation Stock-based compensation is measured at the grant date for all equity awards granted to employees and non-employees based on the fair value of the awards, including stock options and restricted shares. The Company estimates the fair value of stock-based awards on the date of grant using the Black-Scholes option-pricing model. For stock-based awards that vest subject to the satisfaction of a service requirement, the expense is recognized using the straight-line method over the requisite service period, which is generally the vesting period. Forfeitures are accounted for when they occur.
Income Taxes	Income Taxes Income taxes are accounted for using the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts or existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using the enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period of enactment. The Company records a valuation allowance to reduce deferred tax assets to an amount expected to be realized. The Company recognizes the tax benefit from an uncertain tax position if it is more likely than not that the tax position will be sustained upon examination by the tax authorities, based on the merits of the position. The Company’s policy is to recognize interest and penalties related to the underpayment of income taxes as a component of its provision for income taxes. To date, there have been no interest or penalties charged in relation to the unrecognized tax benefits.
Net Loss Per Share	Net Loss Per Share Basic net loss per share is calculated by dividing the net loss by the weighted-average number of shares of the Company’s common stock outstanding for the period, without consideration for potential dilutive shares of common stock. As the Company is in a loss position for the periods presented, diluted net loss per share is the same as basic net loss per share, since the effects of potentially dilutive securities are antidilutive.
Comprehensive Loss	Comprehensive Loss Comprehensive loss includes net loss and certain changes in stockholders’ equity (deficit) that are excluded from net loss. The Company’s comprehensive loss is comprised of unrealized gains and losses on the Company’s available-for-sale investments.
Emerging Growth Company Status	Emerging Growth Company Status The Company is an emerging growth company, as defined in the Jumpstart Our Business Startups Act of 2012, or JOBS Act. Under the JOBS Act, emerging growth companies can delay adopting new or revised accounting standards issued subsequent to the enactment of the JOBS Act until such time as those standards apply to private companies. The Company has elected to use this extended transition period for complying with new or revised accounting standards that have different effective dates for public and private companies until the earlier of the date that it is (a) no longer an emerging growth company or (b) affirmatively and irrevocably opt out of the extended transition period provided in the JOBS Act. As a result, these consolidated financial statements may not be comparable to companies that comply with the new or revised accounting pronouncements as of public company effective dates.
Recently Adopted Accounting Pronouncements	Recently Adopted Accounting Pronouncements In August 2018, the Financial Accounting Standards Board, or FASB issued Accounting Standards Update, or ASU, 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 (a consensus of the FASB Emerging Issues Task Force), or ASU 2018-15. The ASU clarified that implementation, setup and other upfront costs related to cloud computing agreements, or CCA, should be accounted for under ASC 350-40. ASU 2018-15 requires companies to capitalize certain costs incurred when purchasing a CCA that is a service. Under the new guidance, companies should apply the same criteria for capitalizing implementation costs in a CCA service as they would for internal-use software. The capitalized implementation costs should be generally expensed over the term of the service agreement and the related assets should be assessed for impairment using the same model applied to long-lived assets. As an emerging growth company, this new standard is effective for annual periods beginning after December 15, 2020. T he Company adopted this standard prospectively on January 1, 2021 . The adoption did no t have a material impact on the Company’s consolidated financial statements.
Recently Issued Accounting Pronouncements Not Yet Adopted	Recently Issued Accounting Pronouncements Not Yet Adopted In June 2016, the FASB issued ASU 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments , which replaces the existing incurred loss impairment model with an expected credit loss model and requires a financial asset measured at amortized cost to be presented at the net amount expected to be collected. As an emerging growth company, this new standard is effective for the Company in the fiscal year beginning January 1, 2023 and must be adopted using a modified retrospective approach, with certain exceptions. The Company is currently evaluating the impact of this standard on its consolidated financial statements and related disclosures. In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes , or ASU 2019-12, which is intended to simplify the accounting for income taxes. The guidance eliminates certain exceptions to the approach for intra period tax allocation, the methodology for calculating income taxes in an interim period and the recognition of deferred tax liabilities for outside basis differences. As an emerging growth company, this new standard is effective for the Company for fiscal year beginning January 1, 2022. The Company does not expect this standard to have a material impact on its consolidated financial statements and related disclosures.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2021
Fair Value Disclosures [Abstract]
Summary of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis	As of December 31, 2021 and 2020, the carrying amount of prepaid expenses and other current assets, accounts payable and accrued liabilities approximated their estimate fair value due to their relatively short maturities. The following tables present information about the Company’s financial assets and liabilities measured at fair value on a recurring basis and indicates the level of the fair value hierarchy utilized to determine such fair values: December 31, 2021 Level 1 Level 2 Level 3 Fair Value (in thousands) Assets: Money market funds $ 7,794 $ — $ — $ 7,794 Corporate bonds — 4,499 — 4,499 Commercial paper — 187,749 — 187,749 U.S. treasury securities — 16,024 — 16,024 Total financial assets $ 7,794 $ 208,272 $ — $ 216,066 December 31, 2020 Level 1 Level 2 Level 3 Fair Value (in thousands) Assets: Money market funds $ 11,938 $ — $ — $ 11,938 Corporate bonds — 5,671 — 5,671 Commercial paper — 57,195 — 57,195 U.S. treasury securities — 20,196 — 20,196 Total financial assets $ 11,938 $ 83,062 $ — $ 95,000
Summary of Significant Unobservable Inputs Used in Measuring Convertible Preferred Stock Tranche Liability	A summary of the significant unobservable inputs used in measuring the Company’s convertible preferred stock tranche liability as of July 2, 2020 was as follows: July 2, 2020 Time to liquidity (years) 0.01 Probability of second closing 100 % Discount rate 20 %
Summary of Changes in Estimated Fair Value of Convertible Preferred Stock Tranche Liability Measured on Recurring Basis	The following table provides a summary of changes in the estimated fair value of the Company’s convertible preferred stock tranche liability measured on a recurring basis using significant Level 3 inputs: Year Ended 2020 (in thousands) Beginning balance January 1, 2020 $ 2,495 Change in fair value $ ( 214 ) Settlement of convertible preferred stock tranche liability ( 2,281 ) Ending balance December 31, 2020 $ —

Investments (Tables)

Investments (Tables)	12 Months Ended
	Dec. 31, 2021
Investments, Debt and Equity Securities [Abstract]
Summary of Available-For-Sale Debt Securities	The following tables summarize the fair value and amortized cost of the Company’s available-for-sale debt securities by major security type: December 31, 2021 Amortized Gross Gross Aggregate (in thousands) Assets: Money market funds $ 7,794 $ — $ — $ 7,794 Corporate bonds 4,500 — ( 1 ) 4,499 Commercial paper 187,789 17 ( 57 ) 187,749 U.S. treasury securities 16,026 — ( 2 ) 16,024 Total financial assets $ 216,109 $ 17 $ ( 60 ) $ 216,066 December 31, 2020 Amortized Gross Gross Aggregate (in thousands) Assets: Money market funds $ 11,938 $ — $ — $ 11,938 Corporate bonds 5,672 1 ( 2 ) 5,671 Commercial paper 57,197 3 ( 5 ) 57,195 U.S. treasury securities 20,196 2 ( 2 ) 20,196 Total financial assets $ 95,003 $ 6 $ ( 9 ) $ 95,000
Summary of Available-For-Sale Debt Securities On Consolidated Balance Sheets	The following table summarizes the classification of the Company’s available-for-sale debt securities on the consolidated balance sheets: December 31, 2021 2020 (in thousands) Cash equivalents $ 9,882 $ 17,936 Short-term investments 206,184 57,375 Long-term investments — 19,689 Total cash equivalents and investments $ 216,066 $ 95,000
Summary of Fair Value of Available-For-Sale Debt Securities by Contractual Maturity	The following table summarizes the fair values of the Company’s available-for-sale debt securities by contractual maturity: December 31, 2021 2020 (in thousands) Within one year $ 216,066 $ 75,311 After one year through two years — 19,689 Total cash equivalents and investments $ 216,066 $ 95,000

Balance Sheet Components (Table

Balance Sheet Components (Tables)	12 Months Ended
	Dec. 31, 2021
Payables and Accruals [Abstract]
Summary of Accrued and Other Current Liabilities	Accrued and other current liabilities consist of the following: December 31, 2021 2020 (in thousands) Accrued research and development $ 4,213 $ 2,670 Compensation and related benefits 1,881 854 Accrued professional service expenses 207 — Other 332 202 Total accrued and other current liabilities $ 6,633 $ 3,726

Equity (Tables)

Equity (Tables)	12 Months Ended
	Dec. 31, 2021
Equity [Abstract]
Schedule of Convertible Preferred Stock	Convertible preferred stock at December 31, 2020 consisted of the following: Shares Shares Issued and Outstanding Net Carrying Value Liquidation (in thousands, except shares) Convertible Preferred Stock Series A 47,647,051 5,672,256 $ 38,015 $ 40,500 Series B 66,176,463 7,878,135 44,895 45,000 Series C 66,236,125 7,885,241 79,702 80,000 Total 180,059,639 21,435,632 $ 162,612 $ 165,500
Schedule of Common Stock Shares Reserved for Issuance	The Company reserved the following shares of common stock, on an as-if converted basis, for issuance as follows:

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions	The estimated grant-date fair value of the Company’s stock-based awards was calculated using the Black-Scholes option pricing model, based on the following assumptions: Year Ended, 2021 2020 Expected term (in years) 5.8 - 6.1 3.2 - 6.1 Expected volatility 65.2 % - 69.9 % 67.1 % - 95.4 % Risk-free interest rate 0.6 % - 1.5 % 0.36 % - 2.56 % Expected dividend yield —% —%
Schedule of Stock-based Compensation Expense	Total stock-based compensation recognized in the consolidated statements of operations is as follows: Year Ended, 2021 2020 Research and development $ 784 $ 283 General and administrative 1,441 143 Total stock-based compensation expense $ 2,225 $ 426
2012 and 2021 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Schedule of Stock Option Activity	Stock option activity under the 2012 and 2021 Plan was as follows: Options Available for Grant Number of Options Outstanding Weighted-Average Exercise Price Per Share Weighted-Average Aggregate Intrinsic Value (in thousands) Outstanding as of January 1, 2021 1,678,228 1,729,843 $ 2.08 7.75 $ 3,666 Authorized 3,450,000 — — Share rounding difference as a result of the 60 — — Options granted ( 2,867,965 ) 2,867,965 11.76 Options exercised — ( 156,088 ) 3.24 Options cancelled 413,259 ( 413,259 ) 3.18 Outstanding as of December 31, 2021 2,673,582 4,028,461 $ 8.81 8.40 $ 60,089 Exercisable as of December 31, 2021 1,326,075 $ 2.73 6.52 $ 27,826

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Schedule of Effective Tax Rate of Provision for Income Taxes Differs From Federal Statutory Rate	The effective tax rate of the provision for income taxes differs from the federal statutory rate as follows: Year Ended December 31, 2021 2020 U.S. federal taxes at statutory rate 21.0 % 21.0 % State taxes (net of federal benefit) 0.8 2.3 Non-deductible expenses ( 0.2 ) ( 0.3 ) Credits 8.1 11.9 Change in valuation allowance ( 13.1 ) ( 34.9 ) Derecognition due to Section 383 Limitations ( 16.7 ) — Other 0.1 — Effective tax rate —% — %
Schedule of Significant Deferred Tax Assets	The tax effects of temporary differences and carryforwards that give rise to significant portions of deferred tax assets are as follows: December 31, 2021 2020 (in thousands) Deferred tax assets: Net operating loss carryforwards $ 24,827 $ 16,007 Tax credits carryforwards 3,997 7,661 Capitalized start-up costs 546 644 Accrued expenses 436 198 Stock-based compensation 316 64 Other 5 1 Total gross deferred tax assets 30,127 24,575 Less: valuation allowance ( 30,127 ) ( 24,575 ) Total deferred tax assets, net $ — $ —
Schedule of Reconciliation of Unrecognized Tax Benefits	A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows: December 31, 2021 2020 (in thousands) Unrecognized tax benefits, beginning of period $ 2,104 $ 1,391 Gross increases related to prior tax positions 2 23 Gross decreases related to prior tax positions ( 1,894 ) — Lapse of statute of limitations — ( 17 ) Gross increases related to current tax positions 1,174 707 Unrecognized tax benefits, end of period $ 1,386 $ 2,104

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	12 Months Ended
	Dec. 31, 2021
Earnings Per Share [Abstract]
Schedule of Potentially Dilutive Shares Including All Outstanding Stock Options Were Not Included in Calculation of Diluted Shares Outstanding	The following potentially dilutive shares, including all outstanding stock options, were not included in the calculation of diluted shares outstanding for the period presented as the effect would have been anti-dilutive: Year Ended, 2021 2020 Convertible preferred stock — 21,435,632 Outstanding stock options 4,028,461 1,729,843 Total 4,028,461 23,165,475

Organization and Description _2

Organization and Description of the Business - Additional Information (Details)	Jul. 20, 2021USD ($)$ / sharesshares	Jul. 13, 2021	Dec. 31, 2021USD ($)$ / sharesshares	Aug. 20, 2021shares	Dec. 31, 2020USD ($)$ / sharesshares
Organization And Description Of Business [Line Items]
Common stock shares issued			33,531,743		1,030,023
Sale of stock price per share | $ / shares			$ 23.71
Common stock shares authorized			300,000,000		228,300,000
Common stock, par value per share | $ / shares			$ 0.0001		$ 0.0001
Preferred stock, authorized			10,000,000		0
Preferred stock, par value per share | $ / shares			$ 0.0001		$ 0.0001
Accumulated deficit | $			$ 112,653,000		$ 70,342,000
Cash, cash equivalents and short-term investments | $			$ 217,400,000
Reverse stock split			common stock on an 8.4-for-1 basis, or the Reverse Stock Split.
Reverse stock split conversion ratio		0.119048
IPO
Organization And Description Of Business [Line Items]
Common stock shares issued	8,400,000
Sale of stock price per share | $ / shares	$ 16
Proceeds from issuance of common stock | $	$ 140,500,000		$ 143,741,000
Common stock shares authorized	300,000,000
Common stock, par value per share | $ / shares	$ 0.0001
Preferred stock, authorized	10,000,000
Preferred stock, par value per share | $ / shares	$ 0.0001
IPO | Common Stock
Organization And Description Of Business [Line Items]
Convertible preferred stock converted into shares of common stock	21,435,632
Private Placement
Organization And Description Of Business [Line Items]
Common stock shares issued	1,250,000
Proceeds from issuance of common stock | $	$ 20,000		$ 20,000,000
Underwriters Option to Purchase Additional Shares
Organization And Description Of Business [Line Items]
Common stock shares issued				1,260,000

Summary of Significant Accoun_3

Summary of Significant Accounting Policies - Additional Information (Details)	12 Months Ended
	Dec. 31, 2021USD ($)Segment	Dec. 31, 2020USD ($)	Mar. 01, 2020$ / sharesshares
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of operating segments | Segment	1
Number of reportable regments | Segment	1
Accounting Standards Update [Extensible Enumeration]	us-gaap:AccountingStandardsUpdate201815Member
Change in accounting principle, accounting standards update, adoption date	Jan. 1, 2021
Change in accounting principle, accounting standards update, adopted [true false]	true
Change in accounting principle, accounting standards update immaterial effect [true false]	true
Impairment of long-lived assets | $	$ 0	$ 0
Interest or penalties related to uncertain tax positions | $	$ 0	$ 0
Series B Convertible Preferred Stock
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Issuance of convertible preferred stock, net of issuance costs, shares | shares			4,529,931
Shares issued price per share | $ / shares			$ 5.712
Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property plant and equipment, useful life	5 years
Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property plant and equipment, useful life	3 years

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - Fair Value, Recurring - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Assets:
Financial assets	$ 216,066	$ 95,000
Corporate Bonds
Assets:
Financial assets	4,499	5,671
Money Market Funds
Assets:
Financial assets	7,794	11,938
Commercial Paper
Assets:
Financial assets	187,749	57,195
U.S. Treasury Securities
Assets:
Financial assets	16,024	20,196
Level 1
Assets:
Financial assets	7,794	11,938
Level 1 | Money Market Funds
Assets:
Financial assets	7,794	11,938
Level 2
Assets:
Financial assets	208,272	83,062
Level 2 | Corporate Bonds
Assets:
Financial assets	4,499	5,671
Level 2 | Commercial Paper
Assets:
Financial assets	187,749	57,195
Level 2 | U.S. Treasury Securities
Assets:
Financial assets	$ 16,024	$ 20,196

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair value, transfers into level 3	$ 0	$ 0
Fair value, transfers out of level 3	0	0
Convertible Preferred Stock Tranche Liability
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Convertible preferred stock tranche liability	$ 0	$ 0	$ 2,495,000

Fair Value Measurements - Sum_2

Fair Value Measurements - Summary of Significant Unobservable Inputs Used in Measuring Convertible Preferred Stock Tranche Liability (Details) - Level 3	Jul. 02, 2020
Time to Liquidity
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Time to liquidity (years)	3 days
Probability of Second Closing
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Convertible preferred stock tranche liability	1
Discount Rate
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Convertible preferred stock tranche liability	0.20

Fair Value Measurements - Sum_3

Fair Value Measurements - Summary of Changes in Estimated Fair Value of Convertible Preferred Stock Tranche Liability Measured on Recurring Basis (Details) - Convertible Preferred Stock Tranche Liability	12 Months Ended
	Dec. 31, 2020USD ($)
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning balance January 1, 2020	$ 2,495,000
Change in fair value	(214,000)
Settlement of convertible preferred stock tranche liability	(2,281,000)
Ending balance December 31, 2020	$ 0

Investments - Summary of Availa

Investments - Summary of Available-For-Sale Debt Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 216,109	$ 95,003
Gross Unrealized Gains	17	6
Gross Unrealized Losses	(60)	(9)
Aggregate Fair Value	216,066	95,000
Money Market Funds
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	7,794	11,938
Aggregate Fair Value	7,794	11,938
Corporate Bonds
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	4,500	5,672
Gross Unrealized Gains		1
Gross Unrealized Losses	(1)	(2)
Aggregate Fair Value	4,499	5,671
Commercial Paper
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	187,789	57,197
Gross Unrealized Gains	17	3
Gross Unrealized Losses	(57)	(5)
Aggregate Fair Value	187,749	57,195
U.S. Treasury Securities
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	16,026	20,196
Gross Unrealized Gains		2
Gross Unrealized Losses	(2)	(2)
Aggregate Fair Value	$ 16,024	$ 20,196

Investments - Summary of Avai_2

Investments - Summary of Available-For-Sale Debt Securities On Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Cash equivalents	$ 9,882	$ 17,936
Short-term investments	206,184	57,375
Long-term investments		19,689
Total cash equivalents and investments	$ 216,066	$ 95,000

Investments - Summary of Fair V

Investments - Summary of Fair Value of Available-For-Sale Debt Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Within one year	$ 216,066	$ 75,311
After one year through two years		19,689
Total cash equivalents and investments	$ 216,066	$ 95,000

Investments - Additional Inform

Investments - Additional Information (Details)	12 Months Ended
	Dec. 31, 2021USD ($)
Investments, Debt and Equity Securities [Abstract]
Other-than-temporary, available-for-sale debt securities	$ 0

Balance Sheet Components - Summ

Balance Sheet Components - Summary of Accrued and Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Payables and Accruals [Abstract]
Accrued research and development	$ 4,213	$ 2,670
Compensation and related benefits	1,881	854
Accrued professional service expenses	207
Other	332	202
Total accrued and other current liabilities	$ 6,633	$ 3,726

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Rent expense	$ 0.1	$ 0.1

Equity - Schedule of Convertibl

Equity - Schedule of Convertible Preferred Stock (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Temporary Equity [Line Items]
Shares Authorized	0	180,059,639
Shares Issued	0	21,435,632
Shares Outstanding	0	21,435,632
Net Carrying Value	$ 0	$ 162,612
Liquidation Preference	$ 0	$ 165,500
Series A
Temporary Equity [Line Items]
Shares Authorized		47,647,051
Shares Issued		5,672,256
Shares Outstanding		5,672,256
Net Carrying Value		$ 38,015
Liquidation Preference		$ 40,500
Series B
Temporary Equity [Line Items]
Shares Authorized		66,176,463
Shares Issued		7,878,135
Shares Outstanding		7,878,135
Net Carrying Value		$ 44,895
Liquidation Preference		$ 45,000
Series C
Temporary Equity [Line Items]
Shares Authorized		66,236,125
Shares Issued		7,885,241
Shares Outstanding		7,885,241
Net Carrying Value		$ 79,702
Liquidation Preference		$ 80,000

Equity - Additional Information

Equity - Additional Information (Details) - USD ($)	Jul. 20, 2021	Dec. 31, 2021
Class Of Stock [Line Items]
Common stock voting rights		common stock have one vote for each share of common stock.
Dividends declared or accrued		$ 0
Common Stock | IPO
Class Of Stock [Line Items]
Conversion of convertible preferred stock to common stock upon initial public offering, shares	21,435,632	21,435,632

Equity - Schedule of Common Sto

Equity - Schedule of Common Stock Shares Reserved for Issuance (Details) - shares	Dec. 31, 2021	Dec. 31, 2020
Class Of Stock [Line Items]
Common stock, initially reserved for issuance	7,052,043	24,843,703
Reserved for employee stock purchase plan
Class Of Stock [Line Items]
Common stock, initially reserved for issuance	350,000
Conversion of Outstanding Shares of Convertible Preferred Stock
Class Of Stock [Line Items]
Common stock, initially reserved for issuance		21,435,632
Options Available for Future Grant
Class Of Stock [Line Items]
Common stock, initially reserved for issuance	2,673,582	1,678,228
Options Outstanding under 2021 Equity Incentive plan
Class Of Stock [Line Items]
Common stock, initially reserved for issuance	4,028,461	1,729,843

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	12 Months Ended
	Jul. 31, 2021	Dec. 31, 2021	Dec. 31, 2020	Oct. 31, 2012
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, initially reserved for issuance		7,052,043	24,843,703
Common stock price per share		$ 23.71
Total intrinsic value of options exercised		$ 2
Weighted average grant date fair value for stock options granted		$ 7.15	$ 1.20
Expected dividend yield		0.00%
Total unrecognized stock-based compensation expense		$ 18.7
Weighted-average vesting period of unvested stock options		3 years 2 months 12 days
2012 Plan | Employees, Directors and Consultants
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, initially reserved for issuance				238,095
2021 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, initially reserved for issuance	3,450,000
Minimum percentage of voting rights	10.00%
Minimum percentage of fair market value of exercise price for incentive and non-statutory stock options	110.00%
Vesting period	4 years
Common stock reserved for issuance, annual increase, beginning date	Jan. 1, 2022
Common stock reserved for issuance, annual increase, end date	Jan. 1, 2031
Percentage of annual increase in shares reserved for issuance based on common stock outstanding	5.00%
Number of shares available for issuance		2,673,582
2021 Equity Incentive Plan | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expiration term	10 years
2021 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, initially reserved for issuance		350,000
Common stock reserved for issuance, annual increase, beginning date	Jan. 1, 2022
Common stock reserved for issuance, annual increase, end date	Jan. 1, 2031
Percentage of annual increase in shares reserved for issuance based on common stock outstanding	1.00%
Shares authorized	4,703,469
Shares issued		0

Stock-Based Compensation - Sche

Stock-Based Compensation - Schedule of Stock Option Activity (Details) - 2012 and 2021 Plan - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Options Available for Grant
Outstanding at beginning of period	1,678,228
Authorized	3,450,000
Share rounding difference as a result of the reverse stock split	60
Options granted	(2,867,965)
Options cancelled	413,259
Outstanding at end of period	2,673,582	1,678,228
Number of Options Outstanding
Outstanding at beginning of period	1,729,843
Options granted	2,867,965
Options exercised	(156,088)
Options cancelled	(413,259)
Outstanding at end of period	4,028,461	1,729,843
Exercisable at end of period	1,326,075
Weighted-Average Exercise Price Per Share
Outstanding at beginning of period	$ 2.08
Options granted	11.76
Options exercised	3.24
Options cancelled	3.18
Outstanding at end of period	8.81	$ 2.08
Exercisable at end of period	$ 2.73
Weighted-Average Remaining Contractual Life (years)
Outstanding	8 years 4 months 24 days	7 years 9 months
Exercisable	6 years 6 months 7 days
Aggregate Intrinsic Value
Aggregate Intrinsic Value Outstanding	$ 60,089	$ 3,666
Exercisable at end of period	$ 27,826

Stock-Based Compensation - Sc_2

Stock-Based Compensation - Schedule of Estimated Grant-Date Fair Value of Stock-Based Awards Calculated Using Black-Scholes Option Pricing Model (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected volatility, minimum	65.20%	67.10%
Expected volatility, maximum	69.90%	95.40%
Risk-free interest rate, minimum	0.60%	0.36%
Risk-free interest rate, maximum	1.50%	2.56%
Expected dividend yield	0.00%
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	5 years 9 months 18 days	3 years 2 months 12 days
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	6 years 1 month 6 days	6 years 1 month 6 days

Stock-Based Compensation - Sc_3

Stock-Based Compensation - Schedule of Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 2,225	$ 426
Research and Development
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	784	283
General and Administrative
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 1,441	$ 143

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($)	Jun. 29, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 27, 2020
Operating Loss Carryforwards [Line Items]
Income tax expense		$ 2,000	$ 3,000
Changes in valuation allowance		$ 5,600,000	6,200,000
Percentage point aggregate change in ownership		50.00%
Tax cut and jobs act net operating loss deduction limitation percentage		80.00%
Tax credit carryforward, limitations on use		If the Company experiences a greater than 50 percentage point aggregate change in ownership over a three-year period (a Section 382 ownership change), utilization of its pre-change NOL carryforwards are subject to annual limitation under Section 382 of the Internal Revenue Code, or IRC. The annual limitation is deemed by multiplying the value of the Company’s stock at the time of such ownership change by the applicable long-term tax-exempt rate. Such limitations may result in expiration of a portion of the NOL carryforwards before utilization. As of December 31, 2020, the Company determined that ownership changes occurred on October 30, 2014 and November 12, 2020. As a result of the ownership changes, none of the NOLs will expire unutilized for federal, California and Massachusetts purposes, respectively. During the year ended December 31, 2021, the Company completed an analysis and determined that no ownership change occurred under Section 382. Therefore, no derecognized NOL related deferred tax assets in the tax effected amounts for federal and California purposes, respectively. The ability of the Company to use its remaining NOL carryforwards may be further limited if the Company experiences a Section 382 ownership change as a result of future changes in its stock ownership.
Unrecognized tax benefits that would affect effective tax rate if recognized		$ 1,400,000	2,100,000
Interest or penalties related to uncertain tax positions		$ 0	$ 0
Net operating loss carryforwards utilization period		3 years
Income tax examination, description		The Company is not currently under examination by income tax authorities in federal state or other jurisdictions. All tax returns remain open for examination by the federal and state authorities for three and four years, respectively, from the date of utilization of any NOLs or credits.
CAA impact to tax provision				$ 0
California
Operating Loss Carryforwards [Line Items]
Suspension period	3 years
Cap period	3 years
Incentive tax credits offset amount of tax	$ 5,000,000
Taxable income	1,000,000
California | Minimum
Operating Loss Carryforwards [Line Items]
Taxable income	$ 1,000,000
California | Research and Development
Operating Loss Carryforwards [Line Items]
Tax credit carryforwards, indefinite		$ 400,000
Massachusetts | Research and Development
Operating Loss Carryforwards [Line Items]
Tax credit carryforwards		$ 200,000
Tax credit carryforwards, expiration year		2032
California or Massachusetts | Research and Development
Operating Loss Carryforwards [Line Items]
Tax credit carryforward derecognized amount		$ 0
Federal
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards		$ 106,900,000
Operating loss carryforwards, expiration year		2033
Operating loss carryforwards, expiration period		indefinitely
Operating loss carryforwards, indefinite		$ 76,900,000
Tax cut and jobs act net operating loss, period		20 years
Net operating loss carryforwards utilization period		3 years
Federal | Research and Development
Operating Loss Carryforwards [Line Items]
Tax credit carryforwards		$ 100,000
Tax credit carryforwards, expiration year		2040
Tax credit carryforward derecognized amount		$ 500,000
Federal | Orphan Drug
Operating Loss Carryforwards [Line Items]
Tax credit carryforwards		$ 4,800,000
Tax credit carryforwards, expiration year		2037
Tax credit carryforward derecognized amount		$ 8,400,000
Federal | California
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards derecognized		$ 0
State
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards expiration beginning year		2033
Net operating loss carryforwards expiration ending year		2034
Net operating loss carryforwards utilization period		4 years
State | California
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards		$ 400,000
State | Massachusetts
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards		34,100,000
State | New Hampshire
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards		$ 2,700,000

Income Taxes - Schedule of Effe

Income Taxes - Schedule of Effective Tax Rate of Provision for Income Taxes Differs From Federal Statutory Rate (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
U.S. federal taxes at statutory rate	21.00%	21.00%
State taxes (net of federal benefit)	0.80%	2.30%
Non-deductible expenses	(0.20%)	(0.30%)
Credits	8.10%	11.90%
Change in valuation allowance	(13.10%)	(34.90%)
Derecognition due to Section 383 Limitations	(16.70%)
Other	0.10%
Effective tax rate

Income Taxes - Schedule of Sign

Income Taxes - Schedule of Significant Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deferred Tax Assets, Net [Abstract]
Net operating loss carryforwards	$ 24,827	$ 16,007
Tax credits carryforwards	3,997	7,661
Capitalized start-up costs	546	644
Accrued expenses	436	198
Stock-based compensation	316	64
Other	5	1
Total gross deferred tax assets	30,127	24,575
Less: valuation allowance	(30,127)	(24,575)
Total deferred tax assets, net	$ 0	$ 0

Income Taxes - Schedule of Reco

Income Taxes - Schedule of Reconciliation of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Unrecognized tax benefits, beginning of period	$ 2,104	$ 1,391
Gross increases related to prior tax positions	2	23
Gross decreases related to prior tax positions	(1,894)
Lapse of statute of limitations		(17)
Gross increases related to current tax positions	1,174	707
Unrecognized tax benefits, end of period	$ 1,386	$ 2,104

Net Loss Per Share - Schedule o

Net Loss Per Share - Schedule of Potentially Dilutive Shares Including All Outstanding Stock Options Were Not Included in Calculation of Diluted Shares Outstanding (Details) - shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive shares	4,028,461	23,165,475
Convertible Preferred Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive shares		21,435,632
Outstanding Stock Options
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive shares	4,028,461	1,729,843