Inozyme Pharma (INZY) 10-K 15 Mar 22 2021 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Mar. 10, 2022	Jun. 30, 2021
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Annual Report	true
Document Transition Report	false
Document Period End Date	Dec. 31, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Entity Registrant Name	INOZYME PHARMA, INC.
Entity Central Index Key	0001693011
Entity Incorporation, State or Country Code	DE
Entity File Number	001-39397
Entity Tax Identification Number	38-4024528
Entity Address, Address Line One	321 Summer Street
Entity Address, Address Line Two	Suite 400
Entity Address, City or Town	Boston
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02210
City Area Code	857
Local Phone Number	330-4340
Title of 12(b) Security	Common stock, par value $0.0001 per share
Trading Symbol	INZY
Security Exchange Name	NASDAQ
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
ICFR Auditor Attestation Flag	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		23,672,566
Entity Public Float			$ 245,164,789
Documents Incorporated by Reference	The registrant intends to file a definitive proxy statement pursuant to Regulation 14A within 120 days of the end of the fiscal year ended December 31, 2021. Portions of such definitive proxy statement are incorporated by reference into Part III of this Annual Report on Form 10-K.
Auditor Firm ID	42
Auditor Location	Boston, Massachusetts
Auditor Name	Ernst & Young LLP

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 23,316	$ 28,040
Short-term investments	88,485	119,657
Prepaid expenses and other current assets	3,541	3,282
Total current assets	115,342	150,979
Property and equipment, net	2,383	2,648
Right-of-use assets	2,053	0
Restricted cash	354	354
Long-term investments	0	12,199
Prepaid expenses - noncurrent	3,409	3,183
Total assets	123,541	169,363
Current liabilities:
Accounts payable	2,394	3,069
Accrued expenses	8,508	6,904
Operating lease liabilities	731	0
Total current liabilities	11,633	9,973
Operating lease liabilities, net of current portion	2,640	1,287
Total liabilities	14,273	11,260
Commitments (Note 7)
Stockholders' equity
Preferred Stock, $0.0001 par value - 5,000,000 shares authorized at December 31, 2021 and December 31, 2020; No shares issued and outstanding at December 31, 2021 or December 31, 2020	0	0
Common Stock, $0.0001 par value - 200,000,000 shares authorized at December 31, 2021 and December 31, 2020; 23,668,747 shares issued and outstanding at December 31, 2021 and 23,384,969 shares issued and outstanding at December 31, 2020	2	2
Additional paid in-capital	256,948	249,175
Accumulated other comprehensive income	18	2
Accumulated deficit	(147,700)	(91,076)
Total stockholders' equity	109,268	158,103
Total liabilities, convertible preferred stock and stockholders' equity	$ 123,541	$ 169,363

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2021	Dec. 31, 2020
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	23,668,747	23,384,969
Common stock, shares outstanding	23,668,747	23,384,969

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Operating expenses:
Research and development	$ 37,720	$ 46,493
General and administrative	18,926	10,548
Total operating expenses	56,646	57,041
Loss from operations	(56,646)	(57,041)
Other income (expense):
Interest income	211	370
Other income (expense), net	(189)	247
Other income, net	22	617
Net loss	(56,624)	(56,424)
Other comprehensive income (loss):
Unrealized losses on available-for-sale securities	(4)	(3)
Foreign currency translation adjustment	20	0
Total other comprehensive income (loss)	16	(3)
Comprehensive loss	(56,608)	(56,427)
Net loss attributable to common stockholders—basic and diluted	$ (56,624)	$ (56,424)
Net loss per share attributable to common stockholders—basic and diluted	$ (2.40)	$ (5.11)
Weighted-average common shares outstanding—basic and diluted	23,558,306	11,036,500

CONSOLIDATED STATEMENTS OF CONV

CONSOLIDATED STATEMENTS OF CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY (DEFICIT) - USD ($) $ in Thousands	Total	Series A Convertible Preferred Stock [Member]	Series A-2 Convertible Preferred Stock [Member]	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income	Accumulated Deficit
Balance at Dec. 31, 2019	$ (33,219)				$ 1,428	$ 5	$ (34,652)
Temporary equity, shares at Dec. 31, 2019		48,850,000	23,566,431
Temporary equity, balance at Dec. 31, 2019		$ 44,657	$ 33,270
Balance, shares at Dec. 31, 2019				1,204,630
Issuance of Series A-2 Convertible Preferred Stock, net of issuance costs of $0.1 million			$ 33,638
Issuance of Series A-2 Convertible Preferred Stock,net of issuance costs, shares			23,566,431
Issuance of shares to acquire in-process research and development			$ 17,759
Issuance of shares to acquire in-process research and development, shares			8,294,360
Initial public offering, net of issuance costs	115,915			$ 1	115,914
Initial public offering, net of issuance costs, shares				8,050,000
Conversion of convertible preferred stock into common stock	129,324	$ (44,657)	$ (84,667)	$ 1	129,323
Conversion of convertible preferred stock into common stock, shares		(48,850,000)	(55,427,222)	13,953,850
Stock-based compensation	2,308				2,308
Exercise of stock options	202				202
Exercise of stock options, shares				176,489
Comprehensive income:
Unrealized gain on investments	(3)					(3)
Net loss	(56,424)						(56,424)
Balance at Dec. 31, 2020	158,103			$ 2	249,175	2	(91,076)
Balance, shares at Dec. 31, 2020				23,384,969
Stock-based compensation	7,164				7,164
Exercise of stock options	$ 609				609
Exercise of stock options, shares	283,778			283,778
Comprehensive income:
Unrealized gain on investments	$ (4)					(4)
Foreign currency translation adjustment	20					20
Net loss	(56,624)						(56,624)
Balance at Dec. 31, 2021	$ 109,268			$ 2	$ 256,948	$ 18	$ (147,700)
Balance, shares at Dec. 31, 2021				23,668,747

CONSOLIDATED STATEMENTS OF CO_2

CONSOLIDATED STATEMENTS OF CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY (DEFICIT) (Parenthetical) $ in Millions	12 Months Ended
	Dec. 31, 2020USD ($)
Issuance costs	$ 3.9
Series A-2 Convertible Preferred Stock [Member]
Issuance costs	$ 0.1

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Operating activities
Net loss	$ (56,624)	$ (56,424)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation expense	674	217
Write-off of acquired in-process research and development	0	17,759
Stock-based compensation expense	7,164	2,308
Amortization of premiums and discounts on marketable securities	170	277
Reduction in the carrying value of right-of-use assets	378	0
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	(259)	(2,954)
Accounts payable	(675)	2,098
Accrued expenses	1,871	3,928
Operating lease liabilities	(626)	0
Prepaid expenses - noncurrent	(226)	0
Other assets	0	(3,183)
Net cash used in operating activities	(48,153)	(35,974)
Investing activities
Purchases of marketable securities	(121,967)	(177,922)
Maturities of marketable securities	165,160	61,311
Purchases of property and equipment	(397)	(568)
Net cash provided by (used in) investing activities	42,796	(117,179)
Financing activities
Proceeds from issuance of Series A-2 Convertible Preferred Stock, net of issuance costs	0	33,638
Proceeds from exercise of stock options	609	202
Proceeds from initial public offering, net of offering costs	0	115,972
Net cash provided by financing activities	609	149,812
Net decrease in cash, cash equivalents and restricted cash	(4,748)	(3,341)
Effect of foreign currency exchange rate in cash	24	0
Cash, cash equivalents and restricted cash at beginning of period	28,394	31,735
Cash, cash equivalents and restricted cash at end of period	23,670	28,394
Supplemental cash flow information:
Cash and cash equivalents	23,316	28,040
Restricted cash	354	354
Cash, cash equivalents and restricted cash at end of period	23,670	28,394
Issuance of shares to acquire in-process research and development	0	17,759
Property and equipment unpaid at end of period	12	605
Right-of-use asset at adoption of Topic 842	2,431	0
Operating lease liabilities at adoption of Topic 842	3,997	0
Deferred offering costs in accrued expenses	0	57
Deferred lease obligations - non-cash	$ 0	$ 1,394

Organization and Basis of Prese

Organization and Basis of Presentation	12 Months Ended
	Dec. 31, 2021
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Organization and Basis of Presentation	1. Organization and Basis of Presentation Inozyme Pharma, Inc. (the “Company”) is a clinical-stage rare disease biopharmaceutical company developing novel therapeutics for the treatment of diseases of abnormal mineralization impacting the vasculature, soft tissue and skeleton. The Company is pursuing the development of therapeutics to address the underlying causes of these debilitating diseases. It is well established that two genes, ENPP1 and ABCC6, play key roles in a critical mineralization pathway and that defects in these genes lead to abnormal mineralization. The Company is initially focused on developing a novel therapy to treat rare genetic diseases of ENPP1 and ABCC6 Deficiencies. The Company’s lead product candidate, INZ-701, is a soluble, recombinant, or genetically engineered, fusion protein that is designed to correct a defect in the mineralization pathway caused by ENPP1 and ABCC6 Deficiencies. This pathway is central to the regulation of calcium deposition throughout the body and is further associated with neointimal proliferation, or the overgrowth of smooth muscle cells inside blood vessels. On July 17, 2020, the Company effected a one-for-7.4730 reverse stock split of the Company’s common stock. All share and per share amounts in the consolidated financial statements and notes thereto have been retroactively adjusted for all periods presented to give effect to this reverse stock split, including reclassifying an amount equal to the reduction in par value of common stock to additional paid-in capital. Shares of common stock underlying outstanding stock options and other equity instruments were proportionately reduced and the respective exercise prices, if applicable, were proportionately increased in accordance with the terms of the appropriate securities agreements. Shares of common stock reserved for issuance upon the conversion of the Company’s convertible preferred stock were proportionately reduced and the respective conversion prices were proportionately increased. Stockholders entitled to fractional shares as a result of the reverse stock split received a cash payment in lieu of receiving fractional shares. On July 28, 2020, the Company completed its initial public offering (“IPO”) pursuant to which it issued 7,000,000 shares of its common stock at a public offering price of $ 16.00 per share, and on July 30, 2020, the Company sold an additional 1,050,000 shares pursuant to the exercise by the underwriters of their option to purchase additional shares. The Company received net proceeds from its IPO, inclusive of the exercise by the underwriters of their option to purchase additional shares, of $ 115.9 million, after deducting underwriting discounts and commissions and offering expenses . Upon the closing of the IPO, all 104,277,222 shares of the then outstanding preferred stock automatically converted into 13,953,850 shares of common stock. Basis of Presentation The accompanying consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Update (“ASU”) of the Financial Accounting Standards Board (“FASB”). Liquidity, Capital Resources, and Going Concern Since the Company’s incorporation in 2017 and through December 31, 2021, the Company has devoted substantially all of its efforts to raising capital, building infrastructure, developing intellectual property and conducting research and development. The Company incurred net losses of $ 56.6 million and $ 56.4 million in the years ended December 31, 2021 and 2020, respectively, and had an accumulated deficit of $ 147.7 million as of December 31, 2021. The Company had cash, cash equivalents, and short-term investments of $ 111.8 million as of December 31, 2021. The Company had cash, cash equivalents, short-term investments and long-term investments of $ 159.9 million as of December 31, 2020. Because of the numerous risks and uncertainties associated with product development, the Company is unable to predict the timing or amount of increased expenses or when or if the Company will be able to achieve or maintain profitability. Even if the Company is able to generate revenue from product sales, the Company may not become profitable. If the Company fails to become profitable or is unable to sustain profitability on a continuing basis, then the Company may be unable to continue its operations at planned levels and be forced to reduce or terminate its operations. The Company has incurred recurring losses and negative cash flows from operations since inception and has primarily funded its operations with proceeds from the issuance of convertible preferred stock, and with proceeds from the Company’s IPO completed on July 28, 2020. The Company expects its operating losses and negative operating cash flows to continue into the foreseeable future as it continues to expand its research and development efforts. The Company's available cash, cash equivalents, and short-term investments as of December 31, 2021 may not be sufficient to fund its operating expenses and capital expenditure requirements for at least twelve months from the date of filing this Annual Report on Form 10-K. To continue as a going concern, the Company will need additional funding to support its planned operating activities. The Company continually assesses multiple options to obtain additional funding to support its operations, including proceeds from offerings of the Company’s equity securities or debt, cash received from the exercise of outstanding common stock options, or transactions involving technology licensing or collaboration arrangements, or other sources of capital. Although the Company has successfully obtained financing in the past, management can provide no assurances that it will be successful in obtaining additional financing for the Company on favorable terms, if at all. In accordance with ASC Subtopic 205-40, Financial Statement Presentation - Going Concern , future financing activities that are not probable of being implemented and probable of alleviating the conditions that raise substantial doubt are not included in the Company's going concern assessment. If the Company is unable to obtain additional funding, it would be forced to delay, reduce or eliminate some or all of its research and development programs, preclinical studies and clinical trials, or commercialization efforts, which could adversely affect its business prospects. Due to these uncertainties, there is substantial doubt about the Company's ability to continue as a going concern. The accompanying consolidated financial statements have been prepared on the basis of continuity of operations, realization of assets, and the satisfaction of liabilities and commitments in the ordinary course of business. The consolidated financial statements do not include any adjustments relating to the recoverability and classification of recorded asset amounts or the amounts and classification of liabilities that might result from the outcome of this going concern uncertainty.

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 Principles of Consolidation The accompanying consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries, Inozyme Securities Corp., which is a Massachusetts subsidiary created to buy, sell, and hold securities, Inozyme Ireland Limited, and Inozyme Pharma Switzerland GmbH. All intercompany transactions and balances have been eliminated. Use of Estimates The preparation of the Company’s financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. Estimates and judgments are based on historical information and other market-specific or various relevant assumptions, including, in certain circumstances, future projections that management believes to be reasonable under the circumstances. Actual results could differ materially from estimates. Significant estimates and assumptions are used for, but not limited to the accruals for research and development expenses, the fair value of equity instruments issued prior to the IPO, and the grant date fair value of stock-based awards. For equity instruments issued prior to the completion of the Company’s IPO, the Company utilized various valuation methodologies in accordance with the framework of the 2013 American Institute of Certified Public Accountants Technical Practice Aid, Valuation of Privately-Held Company Equity Securities Issued as Compensation , to estimate the fair value of its equity instruments. The Company evaluates its estimates and assumptions on an ongoing basis. All revisions to accounting estimates are recognized in the period in which the estimates are revised and in any future periods affected. Concentration of Credit Risk and Off-Balance Sheet Risk Financial instruments that potentially subject the Company to significant concentrations of credit risk consist primarily of cash, cash equivalents and short-term investments and, from time to time, long-term investments. The Company maintains deposits in federally insured financial institutions in excess of federally insured limits and limits its exposure to credit risk by placing its cash with high credit quality financial institutions. The Company’s investments are comprised of U.S. Treasury and U.S. government agency debt securities and commercial paper of corporations. The Company mitigates credit risk by maintaining a diversified portfolio and limiting the amount of investment exposure as to institution, maturity and investment type. The Company has no significant off-balance sheet risk such as foreign exchange contracts, option contracts, or other foreign hedging arrangements. Cash and Cash Equivalents The Company considers all highly liquid investments with original maturities of three months or less at the date of purchase to be cash equivalents. Cash and cash equivalents include cash in readily available checking accounts, money market accounts and certain marketable securities. Cash is carried at cost, which approximates its fair value. Cash equivalents are carried at fair market value. Restricted Cash Restricted cash is composed of amounts held to collateralize the letter of credit related to the Company’s lease arrangements. Restricted cash is classified as either current or non-current based on the terms of the underlying lease arrangement. Short-Term and Long-Term Investments The Company classifies its investments as available-for-sale and records such assets at estimated fair value on the balance sheet, with unrealized gains and losses on marketable securities, if any, reported as a component of accumulated other comprehensive income (loss). Realized gains and losses are calculated based on the specific-identification method and are recorded as a component of interest income. There have been no realized gains and losses for the years ended December 31, 2021 and 2020 . The Company periodically reviews available-for-sale securities for other-than-temporary declines in fair value below the cost basis whenever events or changes in circumstances indicate the carrying amount of an asset may not be recoverable. Marketable securities with a maturity date of one year or less from the balance sheet date are classified by the Company as short-term investments. Marketable securities with a maturity date of greater than one year from the balance sheet date are classified as long-term investments and are available to fund operations as needed. As of December 31, 2021, the Company did no t have any long-term investments. In accordance with the Company’s investment policy, at the time of purchase, the final maturity of each security within the portfolio shall not exceed 18 months and the weighted average maturity of the portfolio will be no greater than 12 months. Property and Equipment Property and equipment are stated at cost, less accumulated depreciation. Depreciation is calculated using the straight-line method over the estimated useful lives of the assets. Leasehold improvements are amortized over the shorter of the lease term or the estimated useful life of the related asset. The estimated useful lives of the Company’s property and equipment are as follows: Estimated Useful Life (In Years) Laboratory equipment and manufacturing equipment 5 Furniture and fixtures 5 Computer equipment and software 3 Leasehold improvements Lesser of asset life or lease term Impairment of Long-lived Assets As required under the applicable accounting guidance, the Company periodically reevaluates the original assumptions and rationale used in the establishment of the carrying value and estimated lives of all of its long-lived assets, including property and equipment. The Company reviews long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of the assets may not be recoverable. An impairment loss is recognized when the total of estimated future undiscounted cash flows, expected to result from the use of the asset and its eventual disposition, are less than its carrying amount. Impairment, if any, would be assessed using discounted cash flows or other appropriate measures of fair value. There were no impairments for the years ended December 31, 2021 and 2020 . Accrued Research and Development Costs The Company records accrued liabilities for estimated costs of research and development activities conducted by service providers for sponsored research, preclinical studies, clinical operations, and contract manufacturing activities. The Company records the estimated costs of research and development activities based upon the estimated amount of services provided but not yet invoiced and includes these costs in accrued expenses in the accompanying consolidated balance sheets and within research and development expense in the accompanying consolidated statements of operations and comprehensive loss. The Company accrues for these costs based on factors such as estimates of the work completed and in accordance with agreements established with service providers. The Company makes significant judgments and estimates in determining the accrued liabilities balance in each reporting period. As actual costs become known, the Company adjusts its accrued liabilities. The Company has not experienced any material differences between accrued costs and actual costs incurred since its inception. Research and Development Costs Research and development costs are expensed as incurred. Research and development costs consist of direct and indirect internal costs related to specific projects as well as fees paid to other entities that conduct certain research and development activities on the Company’s behalf. Research and development costs also include the write-off of acquired in-process research and development assets with no future use. Patent Costs The Company expenses all costs as incurred in connection with patent applications, including direct application fees, and the legal and consulting expenses related to making such applications, and such costs are included in general and administrative expenses within the Company’s consolidated statements of operations and comprehensive loss. Stock-Based Compensation Stock-based compensation expense represents the cost of the grant date fair value of employee and non-employee stock option grants and restricted stock awards recognized over the requisite service period of the awards on a straight-line basis. For service-based awards that are subject to graded vesting, the Company has elected to recognize compensation expense on a straight-line basis. The Company has elected to recognize forfeitures as they occur upon adoption of guidance per ASU No. 2016-09, Compensation – Stock Compensation . The Company’s equity incentive plan allows for the issuance of restricted stock awards to employees and non-employees that may be subject to vesting. The unvested shares of any restricted stock awards are held in escrow as the stock award vests or until award holder termination, whichever occurs first. In the event of a termination, the Company has the right of repurchase, at its option, the portion of unvested stock awards from the terminated award holder. Convertible Preferred Stock The Company’s convertible preferred stock was classified as temporary equity and excluded from stockholders’ (deficit) equity as the potential redemption of such stock was outside the Company’s control. The carrying value of the convertible preferred stock was not adjusted to the redemption value until the contingent redemption events were considered to be probable of occurring. All of the Company's convertible preferred stock automatically converted to common stock in July 2020 upon completion of the Company's IPO. Income Taxes Income taxes have been accounted for using the asset and liability method. Under the asset and liability method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates applicable 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 the period that includes the enactment date. A valuation allowance against deferred tax assets is recorded if, based upon the weight of all available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. The Company accounts for income taxes in accordance with authoritative accounting guidance which states the impact of an uncertain income tax position is recognized at the largest amount that is “more likely than not” to be sustained upon audit by the relevant taxing authority. There are no unrecognized tax benefits included in the Company’s consolidated balance sheets at December 31, 2021 or 2020 . The Company’s policy is to recognize interest and penalties related to income tax matters in income tax expense. The Company has no t recognized any interest or penalties in its consolidated statements of operations and comprehensive loss since inception. Leases Prior to January 1, 2021, the Company accounted for leases under Topic 840, Leases . Under Topic 840, the Company categorized leases at their inception as either operating or capital leases. On certain lease arrangements, the Company may receive rent holidays or other incentives. Prior to January 1, 2021, the Company recognized lease costs on a straight-line basis once control of the space was obtained, without regard to deferred payment terms, such as rent holidays, that defer the commencement date of required payments or escalating payment amounts. The difference between required lease payments and rent expense was recorded in accrued expenses in the accompanying consolidated balance sheets as of December 31, 2020. Additionally, incentives received were treated as a reduction of costs over the term of the agreement, as they were considered an inseparable part of the lease agreement. The Company adopted Topic 842 (as defined below) on January 1, 2021. Topic 842 allows the Company to elect a package of practical expedients, which provide that an entity need not reassess: (i) whether any expired or existing contracts are or contain leases; (ii) the lease classification for any expired or existing leases; and (iii) any initial direct costs for any existing leases. Another practical expedient allows the Company to use hindsight in determining the lease term when considering lessee options to extend or terminate the lease and to purchase the underlying asset. The Company has elected to utilize this package of practical expedients and has not elected the hindsight methodology in its implementation of Topic 842. The Company elected to adopt this standard using the optional modified retrospective approach and recognized a cumulative-effect adjustment to the consolidated balance sheet on the date of adoption. Comparative periods have not been restated. With the adoption of Topic 842, the Company’s consolidated balance sheet now contains the following line items: Right-of-use assets, Operating lease liabilities and Operating lease liabilities, net of current portion. As all the existing leases subject to Topic 842 were previously classified as operating leases by the Company, they were similarly classified as operating leases under Topic 840. The Company determines at the inception of an arrangement whether the arrangement contains a lease. If a lease is identified in an arrangement, the Company recognizes a right-of-use asset and liability on its balance sheet and determines whether the lease should be classified as a finance or operating lease. The Company does not recognize assets or liabilities for leases with original lease terms of less than 12 months. Additionally, the Company does not separate lease and non-lease components for all leases. A lease qualifies as a finance lease if any of the following criteria are met at the inception of the lease: (i) there is a transfer of ownership of the leased asset to the Company by the end of the lease term, (ii) the Company holds an option to purchase the leased asset that it is reasonably certain to exercise, (iii) the lease term is for a major part of the remaining economic life of the leased asset, (iv) the present value of the sum of lease payments equals or exceeds substantially all of the fair value of the leased asset, (v) the nature of the leased asset is specialized to the point that it is expected to provide the lessor no alternative use at the end of the lease term. All other leases are recorded as operating leases. Finance and operating lease assets and liabilities are recognized at the lease commencement date based on the present value of the lease payments over the lease term using the discount rate implicit in the lease. If the rate implicit is not readily determinable, the Company utilizes its incremental borrowing rate at the lease commencement date. Operating lease assets are further adjusted for prepaid or accrued lease payments. Operating lease payments are expensed using the straight-line method as an operating expense over the lease term. Finance lease assets are amortized to depreciation expense using the straight-line method over the shorter of the useful life of the related asset or the lease term. Finance lease payments are bifurcated into (i) a portion that is recorded as imputed interest expense and (ii) a portion that reduces the finance liability associated with the lease. The Company did no t have any finance leases recorded on its consolidated balance sheet as of December 31, 2021 and 2020 . Deferred Issuance Costs The Company capitalizes certain legal, professional accounting and other third-party fees that are directly associated with in-process equity financings, including the Company’s IPO, as deferred issuance costs until such financings are consummated. After consummation of such an equity financing, these costs are recorded as a reduction of the proceeds generated as a result of the offering. Should a planned equity financing be abandoned, the deferred issuance costs will be expensed immediately as a charge to operating expenses in the consolidated statements of operations and comprehensive loss. The Company did no t have any deferred issuance costs recorded at December 31, 2021 or December 31, 2020 . Net Loss Per Share The Company follows the two-class method when computing net loss allocable to common securities per share as the Company had previously issued shares that meet the definition of participating securities, which included shares of: (i) Series A Convertible Preferred Stock; and (ii) Series A-2 Convertible Preferred Stock. The two-class method requires a portion of net income to be allocated to the participating securities to determine net income allocable to the common securities. During periods of loss, there is no allocation required under the two-class method since the participating securities do not have a contractual obligation to fund the losses of the Company. Basic net loss per share attributable to common stockholders is computed by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period, without consideration for potentially dilutive securities. Diluted net loss per share is computed by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock and potentially dilutive securities outstanding during the period determined using the treasury-stock and if-converted methods. The Company has generated a net loss in all periods presented, therefore the basic and diluted net loss per share attributable to common stockholders are the same as the inclusion of the potentially dilutive securities would be anti-dilutive. Segments Operating segments are defined as components of an entity for which separate financial information is available and that is regularly reviewed by the Chief Operating Decision Maker (“CODM”) in deciding how to allocate resources to an individual segment and in assessing performance. The Company’s CODM is its Chief Executive Officer. The Company has determined it operates in a single operating segment and has one reportable segment. All long-lived assets of the Company reside in the United States. Comprehensive Income (Loss) The Company is required to report all components of comprehensive income (loss), including net loss, in the financial statements in the period in which they are recognized. Comprehensive income (loss) is defined as the change in equity during a period from transactions and other events and circumstances from non-owner sources. Comprehensive income (loss) is comprised of the Company’s net income (loss), unrealized gains and losses on the Company’s investments and foreign currency translation adjustment and is presented within the consolidated statements of operations and comprehensive loss. Foreign Currency Transactions The Company maintains foreign bank accounts denominated in euros and Swiss francs. Foreign currency transactions are initially recorded by the Company using the exchange rates prevailing at the date of the transaction. At the balance sheet date, cash denominated in foreign currencies is translated at the period-end rates of exchange. Exchange gains and losses arising from the translation of foreign currency items are included in other income (expense), net in the consolidated statements of operations and comprehensive loss. The Company recognized net foreign exchange losses of $ 26 thousand and net foreign exchange gains of $ 247 thousand for the years ended December 31, 2021 and 2020 , respectively. Fair Value Measurements The Company categorizes its assets and liabilities measured at fair value in accordance with the authoritative accounting guidance that establishes a consistent framework for measuring fair value, and expands disclosures for each major asset and liability category measured at fair value on either a recurring or nonrecurring basis. Fair value is defined as the exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. As a basis for considering such assumptions, the guidance establishes a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value as follows: • Level 1- Unadjusted quoted prices in active markets that are accessible at the measurement date for identical assets or liabilities; • Level 2- Quoted prices for similar assets and liabilities in active markets, quoted prices in markets that are not active, or inputs which are observable, either directly or indirectly, for substantially the full term of the asset or liability; or • Level 3- Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e., supported by little or no market activity). Emerging Growth Company Status The Company is an “emerging growth company” (“EGC”) as defined in the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”), and the Company may take advantage of certain exemptions from various reporting requirements that are applicable to other public companies that are not EGCs. As an EGC, the Company can elect to take advantage of the extended transition period afforded by the JOBS Act for the implementation of new or revised accounting standards. The Company has elected to use the extended transition period for complying with new or revised accounting standards, and as a result of this election, the Company’s consolidated financial statements may not be comparable to companies that comply with public company FASB standards’ effective dates. The Company will remain an EGC until December 31, 2025, although if the market value of the Company’s common stock that is held by non-affiliates exceeds $ 700 million as of any June 30 before that time or if the Company has annual gross revenues of $ 1.07 billion or more in any fiscal year, the Company would cease to be an EGC as of December 31 of the applicable year. The Company would also cease to be an EGC if it issued more than $ 1 billion of non-convertible debt over a three-year period.

Recent Accounting Pronouncement

Recent Accounting Pronouncements	12 Months Ended
	Dec. 31, 2021
Accounting Changes And Error Corrections [Abstract]
Recent Accounting Pronouncements	3. Recent Accounting Pronouncements From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies that are adopted by the Company as of the specified effective date. Unless otherwise discussed, the Company believes that the impact of recently issued standards that are not yet effective will not have a material impact on its financial position or results of operations upon adoption. Recently Issued and Adopted Accounting Standards In February 2016, the FASB issued ASU 2016-02, Leases (“Topic 842”) . The new standard, as amended, establishes a right-of-use model and requires a lessee to recognize on the balance sheet a right-of-use asset and corresponding lease liability for all leases with terms longer than 12 months. Leases will be classified as either finance or operating, with classification affecting the pattern of expense recognition in the consolidated statements of operations and comprehensive loss. As a result of the FASB’s issuance of ASU No. 2020-05, “Revenue From Contracts With Customers (Topic 606) and Leases (Topic 842): Effective Dates for Certain Entities”, the new standard is effective for annual periods beginning after December 15, 2021 for nonpublic entities, with early adoption permitted. On January 1, 2021 , the Company early adopted Topic 842 using the modified retrospective approach. The Company recorded operating lease assets (right-of-use assets) of $ 2.4 million and operating lease liabilities of $ 4.0 million and reversed a lease liability of $ 1.6 million related to straight-line rent and incentives. There was no impact to accumulated deficit upon adoption of Topic 842 and comparative periods have been accounted for under Topic 840. The underlying assets of the Company’s leases are primarily office and laboratory space. In August 2018, the FASB issued ASU 2018-15, Intangibles-Goodwill and Other-Internal Use Software: Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract (“ASU 2018-15”). ASU 2018-15 aligns the requirements for capitalizing implementation costs incurred in a cloud computing arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. The accounting for the service element of a hosting arrangement that is a service contract is not affected by these amendments. On January 1, 2021 , the Company adopted this standard and the adoption did not have a material impact on its consolidated financial statements. Recently Issued Accounting Standards Not Yet Adopted In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments-Credit Losses (“Topic 326”): Measurement of Credit Losses on Financial Instruments (“ASU 2016-13”) . ASU 2016-13 and its subsequent related updates establish a new forward-looking “expected loss model” that requires entities to estimate current expected credit losses on accounts receivable and financial instruments by using all practical and relevant information. The new standard and its subsequent related updates are effective for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years, with early adoption permitted. The Company is currently assessing the impact that adopting this standard will have on its consolidated financial statements but does not expect it to be material. In December 2019, the FASB issued ASU 2019-12, Income Taxes – Simplifying the Accounting for Income Taxes . The new guidance simplifies the accounting for income taxes by removing several exceptions in the current standard and adding guidance to reduce complexity in certain areas, such as requiring that an entity reflect the effect of an enacted change in tax laws or rates in the annual effective tax rate computation in the interim period that includes the enactment date. The new standard is effective for fiscal years beginning after December 15, 2021, and interim periods within fiscal years beginning after December 15, 2022 for all non-public entities, with early adoption permitted. The adoption of ASU 2019-12 is not expected to have a material impact on the Company’s consolidated financial statements.

Balance Sheet Details

Balance Sheet Details	12 Months Ended
	Dec. 31, 2021
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Balance Sheet Details	4. Balance Sheet Details Short-term investments consisted of the following (dollar amounts in thousands): December 31, 2021 Description Maturity Amortized Gross Gross Estimated Commercial paper 1 year or less $ 78,456 $ 5 $ ( 3 ) $ 78,458 U.S. Treasury securities 1 year or less 5,025 — — 5,025 U.S. government agency debt securities 1 year or less 5,002 — — 5,002 $ 88,483 $ 5 $ ( 3 ) $ 88,485 December 31, 2020 Description Maturity Amortized Gross Gross Estimated Commercial paper 1 year or less $ 94,873 $ 5 $ ( 6 ) $ 94,872 U.S. Treasury securities 1 year or less 11,614 2 ( 1 ) 11,615 U.S. government agency debt securities 1 year or less 13,169 1 — 13,170 $ 119,656 $ 8 $ ( 7 ) $ 119,657 The Company did no t have any long-term investments at December 31, 2021. Long-term investments at December 31, 2020 consisted of the following (dollar amounts in thousands): December 31, 2020 Description Maturity Amortized Gross Gross Estimated U.S. Treasury securities After 1 year through 5 years $ 5,126 $ — $ — $ 5,126 U.S. government agency debt securities After 1 year through 5 years 7,072 1 — 7,073 $ 12,198 $ 1 $ — $ 12,199 The Company concluded that the declines in market value of available-for-sale securities were temporary in nature and did not consider any of the investments to be other-than-temporarily impaired. In accordance with its investment policy, the Company invests in investment grade securities with high credit quality issuers, and generally limits the amount of credit exposure to any one issuer. The Company evaluates securities for other-than-temporary impairment at the end of each reporting period. Impairment is evaluated considering numerous factors, and their relative significance varies depending on the situation. Factors considered include the length of time and extent to which fair value has been less than the cost basis, the financial condition and near-term prospects of the issuer, and the Company’s intent and ability to hold the investment to allow for an anticipated recovery in fair value. Furthermore, the aggregate of individual unrealized losses that had been outstanding for 12 months or less was not significant as of December 31, 2021 and December 31, 2020. The Company does not intend to sell these investments and it is not more likely than not that the Company will be required to sell the investments before a recovery of their amortized cost bases, which may be maturity. The Company also believes that it will be able to collect both principal and interest amounts due at maturity. Prepaid expenses and other current assets consisted of the following (dollar amounts in thousands): At December 31, 2021 At December 31, 2020 Interest receivable $ 62 $ 155 Prepaid insurance 1,728 1,723 Prepaid research studies 1,190 804 Prepaid other 561 600 Total $ 3,541 $ 3,282 Noncurrent prepaid expenses consisted of the following (dollar amounts in thousands): At December 31, 2021 At December 31, 2020 Prepaid clinical trial and other $ 3,409 $ 3,183 $ 3,409 $ 3,183 Property and equipment consisted of the following (dollar amounts in thousands): At December 31, 2021 At December 31, 2020 Laboratory equipment and manufacturing equipment $ 591 $ 339 Furniture and fixtures 258 254 Computer equipment and software 440 287 Leasehold improvements 2,095 2,095 3,384 2,975 Less accumulated depreciation ( 1,001 ) ( 327 ) Total $ 2,383 $ 2,648 Depreciation expense for the years ended December 31, 2021 and 2020 totaled $ 674 thousand and $ 217 thousand, respectively. Accrued expenses consisted of the following (dollar amounts in thousands): At December 31, 2021 At December 31, 2020 Payroll and related liabilities $ 2,379 $ 2,296 Professional fees 727 454 Research and development costs 5,066 2,997 Deferred rent — 279 Other 336 878 Total $ 8,508 $ 6,904

Fair Value Measurement

Fair Value Measurement	12 Months Ended
	Dec. 31, 2021
Fair Value Disclosures [Abstract]
Fair Value Measurement	5. Fair Value Measurement The following table represents the Company’s financial assets measured at fair value on a recurring basis and indicate the level of fair value hierarchy utilized to determine such fair values (in thousands): Fair Value Measurements at Reporting Date Description December 31, 2021 Quoted Significant Significant Assets: Money market funds (included in cash and cash $ 14,302 $ 14,302 $ — $ — Commercial paper 78,457 — 78,457 — U.S. Treasury securities 5,026 5,026 — — U.S. government agency debt securities 5,002 — 5,002 — Total assets $ 102,787 $ 19,328 $ 83,459 $ — Fair Value Measurements at Reporting Date Description December 31, Quoted Significant Significant Assets: Money market funds (included in cash and cash $ 15,739 $ 15,739 $ — $ — Commercial paper 94,872 — 94,872 — U.S. Treasury securities 16,741 16,741 — — U.S. government agency debt securities 20,243 — 20,243 — Total assets $ 147,595 $ 32,480 $ 115,115 $ — There have been no transfers between fair value levels during the years ended December 31, 2 0 21 and December 31, 2020 .

License and Sponsored Research

License and Sponsored Research Agreements	12 Months Ended
	Dec. 31, 2021
Research And Development [Abstract]
License and Sponsored Research Agreements	6. License and Sponsored Research Agreements In January 2017, the Company entered into a license agreement with Yale University (“Yale”), which was amended in May 2020 and July 2020, under which the Company licensed certain intellectual property related to ectonucleotide pyrophosphatase/phosphodiesterase enzymes that is the basis for the Company’s INZ-701 development program. Pursuant to the license agreement, as partial upfront consideration, the Company made a payment of approximately $ 60 thousand to Yale, which amount reflected unreimbursed patent expenses incurred by Yale prior to the date of the license agreement. The Company is responsible for paying Yale an annual license maintenance fee in varying amounts throughout the term ranging from the low tens of thousands of dollars to the high tens of thousands of dollars. For the years ended December 31, 2021 and 2020, the Company incurred a total of $ 100 thousand and $ 44 thousand, respectively, in license maintenance fees to Yale. The Company is required to pay Yale $ 3.0 million, based on the achievement of a specified net product sales milestone or specified development and commercialization milestones, for each therapeutic and prophylactic licensed product developed. In January 2022, the Company paid Yale a $ 250 thousand milestone payment following dosing of the first patient in Company’s Phase 1/2 clinical trial of INZ-701 in adult patients with ENPP1 Deficiency in November 2021. In addition, the Company is required to pay Yale an amount in the several hundreds of thousands of dollars, based on the achievement of a specified net product sales milestone or specified development and commercialization milestones, for each diagnostic licensed product developed. While the agreement remains in effect, the Company is required to pay Yale low single-digit percentage royalties on aggregate worldwide net sales of certain licensed products. Yale is guaranteed a minimum royalty payment amount (ranging in dollar amounts from the mid six figures to low seven figures) for each year after the first sale of a therapeutic or prophylactic licensed product that results in net sales. Yale is guaranteed a minimum royalty payment amount (ranging from the low tens of thousands of dollars to the mid tens of thousands of dollars) for each year after the first sale of a diagnostic licensed product that results in net sales. The Company must also pay Yale a percentage in the twenties of certain types of income it receives from sublicensees. The Company is also responsible for costs relating to the prosecution and maintenance of the licensed patents. Finally, subject to certain conditions, all payments due by the Company to Yale will be tripled following any patent challenge or challenge to a claim by Yale that a product is a licensed product under the agreement made by the Company against Yale if Yale prevails in such challenge. In January 2017, the Company also entered into a corporate sponsored research agreement with Yale (the “Sponsored Research Agreement”), which was amended in February 2019, under which the Company agreed to provide research support funding in the aggregate amount of $ 2.4 million over the five year period from contract inception through December 2021 . The Sponsored Research Agreement was amended in February 2022, under which the contract was extended through June 30, 2022 subject to the terms of the existing agreement. The Company recorded research and development expenses associated with this arrangement of $ 0.5 million and $ 0.4 million in the years ended December 31, 2021 and 2020 , respectively.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2021
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	7. Commitments and Contingencies Operating Leases The Company held the following significant operating leases of office and laboratory space as of December 31, 2021: • An operating lease for 8,499 square feet of office space in Boston, Massachusetts that expires in 2025 , with an option to extend the term for five years ; and • An operating lease for 6,244 square feet of laboratory space in Boston, Massachusetts that expires in 2025 . Both leases are subject to yearly rent escalations. In connection with the Company’s leases of office space and laboratory space, the Company provided security deposits to the landlords in the form of letters of credit totaling $ 354 thousand. The cash collateralizing the letters of credit is included in restricted cash in the accompanying balance sheets as of December 31, 2021 and December 31, 2020. As all the existing leases subject to Topic 842 were previously classified as operating leases by the Company, they were similarly classified as operating leases under Topic 840. The Company has determined that the identified leases did not contain non-lease components and require no further allocation of the total lease cost. Additionally, the agreements in place did not contain information to determine the rate implicit in the lease. As such, the Company calculated the incremental borrowing rate based on the remaining lease terms as of January 1, 2021. At January 1, 2021, the weighted average incremental borrowing rate and the weighted average remaining lease term for the operating leases held by the Company were 8.0 % and 5.0 years, respectively. At December 31, 2021 , the weighted average incremental borrowing rate and the weighted average remaining lease term for the operating leases held by the Company were 8.0 % and 3.9 years, respectively. During the twelve months ended December 31, 2021 , cash paid for amounts included for the measurement of lease liabilities was $ 0.9 million and the Company recorded operating lease expense of $ 0.7 million. During the twelve months ended December 31, 2020 , cash paid for amounts included for the measurement of lease liabilities was $ 0.6 million and the Company recorded operating lease expense of $ 0.7 million. Future lease payments under non-cancelable leases as of December 31, 2021 are as follows (dollar amounts in thousands): Year Ending December 31, 2022 $ 968 2023 992 2024 1,016 2025 944 Thereafter - $ 3,920 Indemnification Agreements In the ordinary course of business, the Company may provide indemnification of varying scope and terms to vendors, lessors, business partners and other parties with respect to certain matters arising out of the relationship between such parties and the Company. In addition, the Company has entered into indemnification agreements with members of its board of directors and senior management that will require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or service as directors or officers. The maximum potential amount of future payments the Company could be required to make under these indemnification agreements is, in many cases, unlimited. To date, the Company has not incurred any material costs as a result of such indemnifications. The Company is not aware of any claims under indemnification arrangements, and it has not accrued any liabilities related to such obligations as of December 31, 2021 or December 31, 2020. Legal Proceedings The Company is not currently a party to any material legal proceedings. At each reporting date, the Company evaluates whether or not a potential loss amount or a potential range of loss is probable and reasonably estimable under the provisions of the authoritative guidance that addresses accounting for contingencies. The Company expenses the costs related to its legal proceedings as they are incurred. No such costs have been incurred during the years ended December 31, 2021 and 2020 .

Convertible Preferred Stock and

Convertible Preferred Stock and Stockholders' Equity	12 Months Ended
	Dec. 31, 2021
Convertible Preferred Stock And Stockholders Equity [Abstract]
Convertible Preferred Stock and Stockholders' Equity	8. Convertible Preferred Stock and Stockholders’ Equity Convertible Preferred Stock Series A Convertible Preferred Stock In January 2017, the Company converted from a Delaware limited liability company to a Delaware corporation. In connection with the conversion to a corporation, 100,000 shares of Series A Convertible Preferred Stock of the Company were issued to stockholders upon conversion of all outstanding shares of Series A-1 Convertible Preferred Stock of the limited liability company. In January 2017, the Company entered into a Series A Convertible Preferred Stock Purchase Agreement, which was amended and restated in April 2017 (as amended and restated, the “Series A Agreement”) under which it agreed to issue up to 48,750,000 shares of Series A Convertible Preferred Stock in two tranches. Under the Series A Agreement, the Company initially issued 27,083,333 shares at a price of $ 1.00 per share for net cash proceeds of $ 26.7 million from January 2017 through May 2017. The Series A Agreement provided for a second tranche closing based on the achievement of a defined milestone (the “Tranche Right”), pursuant to which the investors were required to purchase, and the Company to sell, an additional 21,666,667 shares of Series A Convertible Preferred Stock at a price of $ 1.00 per share upon the achievement of the defined milestone or waiver of the milestone. In November 2018, the Company sold 21,666,667 shares of Series A Convertible Preferred Stock at a price of $ 1.00 per share for proceeds of $ 21.6 million. The Company concluded that the Tranche Right met the definition of a freestanding financial instrument, as the Tranche Right was legally detachable and separately exercisable from the Series A Convertible Preferred Stock. Therefore, the Company allocated the net proceeds between the Tranche Right and the Series A Convertible Preferred Stock. Since the Series A Convertible Preferred Stock was contingently redeemable upon the occurrence of a deemed liquidation event, the Tranche Right was classified as a liability under ASC Topic 480 Distinguishing Liabilities from Equity and was initially recorded at fair value. The estimated fair value of the Tranche Right was determined using a Black-Scholes option-pricing model. The Tranche Right was remeasured at fair value at each reporting period prior to settlement in November 2018, with changes in fair value recorded as a component of other income (expense) in the consolidated statements of operations and comprehensive loss. The fair value of the Tranche Right was reclassified to Series A Convertible Preferred Stock at settlement. Series A-2 Convertible Preferred Stock In November 2018, the Company entered into a Series A-2 Convertible Preferred Stock Purchase Agreement, which was amended in March 2019 (as so amended, the “Series A-2 Agreement”) under which it agreed to issue up to 47,132,862 shares of Series A-2 Convertible Preferred Stock. Under the Series A-2 Agreement, the Company initially issued 7,482,515 shares at a price of $ 1.43 per share for net proceeds of $ 10.4 million in November 2018 and 16,083,916 shares at a price of $ 1.43 per share for net proceeds of $ 22.9 million in March 2019. The Series A-2 Agreement provided for a second tranche closing, pursuant to which the investors were required to purchase, and the Company to sell, an additional 23,566,431 shares of Series A-2 Convertible Preferred Stock at $ 1.43 per share upon the achievement of the defined milestone, or earlier upon board of directors and requisite stockholder approval to waive such requirement. The Company concluded that the second tranche did not meet the definition of a freestanding financial instrument and therefore did not require separate accounting. In June 2020, the board of directors and requisite stockholders approved such waiver and the Company issued 23,566,431 shares of Series A-2 Convertible Preferred Stock at a price of $ 1.43 per share for net proceeds of $ 33.6 million. In July 2020, the Company increased the number of authorized shares of Series A-2 Convertible Preferred Stock from 47,132,862 to 55,427,222 . In July 2020, the Company issued 8,294,360 shares of Series A-2 Convertible Preferred Stock to Alexion Pharmaceuticals, Inc. (“Alexion”) in consideration for the sale and assignment to the Company of specified patent rights and other specified assets related to ENPP1. In July 2020, the Company eliminated the per share and gross proceeds thresholds for a firm-commitment underwritten public offering that triggers the automatic conversion of all outstanding shares of preferred stock into common stock. On July 28, 2020, upon the closing of the Company’s IPO, all 104,277,222 shares of then outstanding preferred stock automatically converted into 13,953,850 shares of common stock. In addition, on July 28, 2020, the Company amended and restated its certificate of incorporation to authorize 200,000,000 shares of common stock and 5,000,000 shares of preferred stock, which shares of preferred stock are currently undesignated. The Company did no t have any outstanding preferred stock as of December 31, 2021 or as of December 31, 2020. There have been no dividends declared on preferred stock or common stock by the Company’s board of directors as of December 31, 2021. Open Market Sale Agreement On August 11, 2021, the Company filed a universal shelf registration statement on Form S-3, which was declared effective on August 23, 2021, (the "Registration Statement"). Under the Registration Statement, the Company may offer and sell up to $ 200.0 million of a variety of securities, including common stock, preferred stock, depositary shares, debt securities, warrants, subscription rights or units from time to time pursuant to one or more offerings at prices and terms to be determined at the time of the sale. In connection with the filing of the Registration Statement, the Company entered into an Open Market Sale Agreement with Jefferies LLC, as sales agent, pursuant to which the Company may offer and sell shares of its common stock with an aggregate offering price of up to $ 50.0 million under an “at-the-market” offering program. During the year ended December 31, 2021, the Company did not sell any securities under the Open Market Sale Agreement. Equity Incentive Plans In January 2017, the Company’s board of directors and stockholders adopted the 2017 Equity Incentive Plan, which was amended and restated in July 2017, (as so amended and restated, the “2017 Plan”), which provided for the grant of incentive stock options, non-statutory stock options, stock appreciation rights, restricted stock awards, restricted stock unit awards and other stock awards. The maximum number of shares of common stock that were authorized for issuance under the 2017 Plan was 2,730,496 . On July 17, 2020, the Company’s stockholders approved the 2020 Stock Incentive Plan (the “2020 Plan”), which became effective on July 23, 2020. The 2020 Plan provides for the grant of incentive stock options, non-statutory stock options, stock appreciation rights, restricted stock awards, restricted stock units and other stock-based awards. The number of shares of the Company’s common stock reserved for issuance under the 2020 Plan was 1,588,315 shares, plus the 426,065 shares of common stock remaining available for issuance under the 2017 Plan as of July 23, 2020. The number of shares reserved under the 2020 Plan will be annually increased on each January 1 through January 1, 2030 by the lower of (i) 4 % of the number of shares of common stock outstanding on the first day of such fiscal year and (ii) an amount determined by the Company’s board of directors. As of the effective date of the 2020 Plan, no further awards will be made under the 2017 Plan. Any options or awards outstanding under the 2017 Plan are governed by their existing terms. The shares of the Company’s common stock subject to outstanding awards under the 2017 Plan that expire, terminate or are otherwise surrendered, cancelled, forfeited or repurchased by the Company at their original issuance price pursuant to a contractual repurchase right will be added back to the shares of common stock available for issuance under the 2020 Plan. No more than 1,588,315 shares of the Company’s common stock may be granted subject to incentive stock options under the 2020 Plan. As of December 31, 2021 , 904,016 shares of common stock remain available for future issuance under the 2020 Plan. On January 1, 2022 and 2021, the number of shares of common stock reserved under the 2020 Plan was increased by 946,749 shares and 935,398 shares, respectively. The following table summarizes stock option activity under the Company’s equity incentive plans since December 31, 2020: Options Weighted- Weighted- Aggregate (in years) (in thousands) Outstanding at December 31, 2020 3,064,457 $ 7.28 8.76 $ 41,680 Granted 1,314,504 17.16 Exercised ( 283,778 ) 2.15 Forfeited ( 512,570 ) 12.05 Outstanding at December 31, 2021 3,582,613 $ 10.63 8.32 $ 7,428 Exercisable at December 31, 2021 1,427,662 $ 7.09 7.55 $ 4,816 Vested and expected to vest at December 31, 2021 3,582,613 $ 10.63 8.32 $ 7,428 (1) The aggregate intrinsic value of stock options is calculated as the difference between the exercise price of the stock options and the fair value of the Company’s common stock for those stock options that had exercise prices lower than the fair value of the Company’s common stock. The weighted average grant date fair value of stock options granted in the years ended December 31, 2021 and 2020 was $ 12.86 per share and $ 9.15 per share, respectively. The aggregate intrinsic value of stock options exercised during the year ended December 31, 2021 was $ 3.0 million. The aggregate intrinsic value of stock options exercised during the year ended December 31, 2020 was $ 0.7 million. For purposes of calculating stock-based compensation expense, the Company estimates the fair value of stock options using the Black-Scholes option-pricing model. This model incorporates various assumptions, including the expected volatility, expected term, and interest rates. The underlying assumptions used to value stock options granted to participants using the Black-Scholes option-pricing were as follows: Years Ended December 31, 2021 2020 Risk-free interest rate range 0.48 % to 1.37 % 0.36 % to 0.55 % Dividend yield 0 % 0 % Expected term of options (years) 5.37 to 6.48 6.08 to 6.78 Volatility rate range 88.41 % to 91.19 % 86.54 % to 99.85 % Expected Term —The expected term of stock options represents the weighted average period the stock options are expected to be outstanding. The Company uses the simplified method for estimating the expected term, which calculates the expected term as the average time-to-vesting and the contractual life of the options for stock options issued to participants. Expected Volatility —Due to the Company’s limited operating history and lack of company-specific historical or implied volatility, the expected volatility assumption was determined by examining the historical volatilities of a group of industry peers whose share prices are publicly available. The Company expects to continue to do so until such time as it has adequate historical data regarding the volatility of its own traded stock price. Risk-Free Interest Rate —The risk-free rate assumption is based on U.S. Treasury instruments, the terms of which were consistent with the expected term of the Company’s stock options. Expected Dividend —The expected dividend assumption is based on the Company’s history and expectation of dividend payouts. The Company has not paid and does not intend to pay dividends. Fair Value of Common Stock —Historically, the fair value of the shares of common stock underlying the stock options has been determined by the Company’s board of directors. Because there was no public market for the Company’s common stock prior to the Company’s IPO, the board of directors determined fair value of common stock at the time of grant of the option by considering a number of objective and subjective factors including independent third-party valuations of the Company’s common stock, sales of convertible preferred stock to unrelated third parties, operating and financial performance, the lack of liquidity of capital stock and the general and industry specific economic outlook, among other factors. Following the Company’s IPO, the fair value of the Company’s common stock has been determined based on the closing price of the Company’s common stock on the Nasdaq Global Select Market on the grant date, with consideration of whether there is material nonpublic information that could impact that estimated fair value when it is released. For the year ended December 31, 2021 , the Company recognized employee-related stock-based compensation expense of $ 5.5 million and non-employee stock-based compensation expense of $ 1.6 million. For the year ended December 31, 2020 , the Company recognized employee-related stock-based compensation expense of $ 1.8 million and non-employee stock-based compensation expense of $ 0.5 million. The fair value of shares vested for the years ended December 31, 2021 and 2020 was $ 6.5 million and $ 1.3 million, respectively. The total unrecognized compensation cost related to outstanding employee awards as of December 31, 2021 was $ 19.3 million and is expected to be recognized over a weighted average period of 2.8 years. Employee Stock Purchase Plan On July 17, 2020, the Company’s stockholders approved the 2020 Employee Stock Purchase Plan (the “ESPP”), which became effective on July 23, 2020. The ESPP initially provides participating employees with the opportunity to purchase up to an aggregate of 198,539 shares of the Company’s common stock. The number of shares of common stock reserved for issuance under the ESPP will automatically increase on January 1, 2021 and each January 1 thereafter through January 1, 2031, in an amount equal to the lowest of (1) 397,079 shares of the Company’s common stock, (2) 1 % of the number of shares of the Company’s common stock outstanding on the first day of such fiscal year and (3) an amount determined by the Company’s board of directors. As of December 31, 2021 , no shares have been purchased by employees under the ESPP. On January 1, 2022 and 2021, the number of shares of common stock reserved under the ESPP was increased by 236,687 shares and 233,849 shares, respectively.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Income Tax	9. Income Taxes During the years ended December 31, 2021 and 2020, the Company recorded net losses of $ 56.6 million and $ 56.4 million, respectively. Since it maintains a full valuation allowance on its deferred tax assets, the Company did no t record an income tax benefit for the years ended December 31, 2021 and 2020. A reconciliation of the U.S. federal statutory income tax rate to the Company’s effective income tax rate is as follows: Year Ended December 31, 2021 2020 Federal income tax at statutory rate 21.0 % 21.0 % Permanent differences ( 1.6 ) ( 0.5 ) State income tax, net of federal benefit 5.4 5.0 Federal and state research and development tax credits 6.8 0.9 Valuation allowance ( 31.6 ) ( 26.4 ) Effective income tax rate — % — % Deferred taxes are recognized for temporary differences between the bases of assets and liabilities for financial statement and income tax purposes. The significant components of the Company’s deferred tax assets as of December 31, 2021 and 2020 are comprised of the following (dollar amounts in thousands): December 31, 2021 2020 Deferred tax assets: Net operating losses $ 31,110 $ 17,712 Research and development credits 5,268 1,007 Stock options 833 157 Accrued expenses 490 594 Deferred rent — 408 Amortization 4,194 4,520 Lease liability 875 — Other 96 173 Gross deferred tax assets 42,866 24,571 Less: Valuation allowance ( 42,056 ) ( 24,199 ) Net deferred tax assets 810 372 Deferred tax liabilities: Depreciation of fixed assets ( 277 ) ( 372 ) Right of use assets ( 533 ) — Gross deferred tax liabilities ( 810 ) ( 372 ) Non-current net deferred tax assets (liabilities) $ — $ — As of December 31, 2021 , the Company had gross federal operating loss carryforwards of $ 121.3 million, which may be available to offset future taxable income. Of the federal operating loss carryforwards, $ 5.6 million begin to expire in 2037 and $ 115.7 million do not expire. As of December 31, 2021 , the Company had gross state operating loss carryforwards of $ 92.0 million, which may be available to offset future taxable income and which begin to expire in 2037 . As required by FASB ASC Topic 740, Income Taxes , management of the Company has evaluated the positive and negative evidence bearing upon the realizability of its deferred tax assets, which are comprised principally of net operating loss carryforwards and research and development credits. Under the applicable accounting standards, management has considered the Company’s history of losses and concluded that it is more likely than not that the Company will not recognize the benefits of federal and state deferred tax assets. Accordingly, a full valuation allowance of $ 42.1 million and $ 24.2 million has been established at December 31, 2021 and December 31, 2020 , respectively. The increase in the valuation allowance of $ 17.9 million during 2021 was primarily due to the increase in net operating loss generated by the Company. The Company also has federal and state research and development credit carryforwards totaling $ 5.4 million as of December 31, 2021 . The federal research and development credit carryforwards will begin to expire in 2037 , unless previously utilized. The state research and development credit carryforwards will begin to expire in 2041 , unless previously utilized. The Company has generated research credits, but has not conducted a study to document the qualified activity. This study may result in an adjustment to the Company’s research and development credit carryforwards; however, until a study is completed and any adjustment is known, no amounts are being presented as an uncertain tax position. A full valuation allowance has been provided against the Company’s research and development credits and, if an adjustment is required, this adjustment would be offset by an adjustment to the deferred tax asset established for the research and development credit carryforwards and the valuation allowance. The Company’s ability to use its net operating loss carryforwards (“NOLs”) and tax credit carryforwards to offset taxable income is subject to restrictions under Sections 382 and 383 of the United States Internal Revenue Code (the “Internal Revenue Code”). Under the Internal Revenue Code provisions, certain substantial changes in the Company’s ownership, including the sale of the Company or significant changes in ownership due to sales of equity, have limited and may limit in the future, the amount of NOLs which could be used annually to offset future taxable income. The Company has not yet conducted an analysis of ownership changes. The Company may also experience ownership changes in the future as a result of subsequent shifts in its stock ownership, some of which may be outside the Company’s control. As a result, the Company’s ability to use its pre-change NOLs to offset U.S. federal taxable income may be subject to limitations, which could potentially result in increased future tax liability to the Company. In addition, at the state level, there may be periods during which the use of NOLs is suspended or otherwise limited, which could accelerate or permanently increase state taxes owed. Under the TCJA, the use of federal NOLs arising in taxable years beginning after December 31, 2017 is limited to 80 % of current year taxable income and NOLs arising in taxable years ending after December 31, 2017 may not be carried back (though any such NOLs may be carried forward indefinitely). The Coronavirus Aid, Relief, and Economic Security (CARES) Act, enacted on March 27, 2020, retroactively and temporarily (for taxable years beginning before January 1, 2021) suspended application of the 80 %-of-income limitation on the use of NOLs and provides that NOLs arising in any taxable year beginning after December 31, 2017, and before January 1, 2021 are generally eligible to be carried back up to five years. The Company establishes reserves for uncertain tax positions based on management’s assessment of exposures associated with tax positions taken on tax return filings. The tax reserves are analyzed periodically and adjustments are made as events occur to warrant adjustment to the reserve. The Company does not have any reserves for uncertain tax positions as of December 31, 2021 and any change in position would result in a change in the valuation allowance maintained against its net deferred tax assets. Interest and penalty charges, if any, related to unrecognized tax benefits would be classified as income tax expense in the accompanying consolidated statements of operations and comprehensive loss. As of December 31, 2021, the Company had no accrued interest related to uncertain tax positions. Since the Company is in a loss carryforward position, the Company is generally subject to examination by the U.S. federal, state and local income tax authorities for all tax years in which a loss carryforward is available. The tax law changes in the CARES Act did not have a material impact on the Company’s income 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 Net Loss per Share Attributable to Common Stockholders The Company has generated a net loss in all periods presented, therefore the basic and diluted net loss per share attributable to common stockholders are the same as the inclusion of the potentially dilutive securities would be anti-dilutive. The Company excluded the following potential dilutive securities, presented based on amounts outstanding at December 31, 2021 and 2020, from the computation of diluted net loss per share attributable to common stockholders because including them would have had an anti-dilutive effect: Year Ended December 31, 2021 2020 Options to purchase common stock 3,582,613 3,064,457 3,582,613 3,064,457

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2021
Compensation And Retirement Disclosure [Abstract]
Employee Benefit Plans	11. Employee Benefit Plans The Company established a defined contribution savings plan in 2018 for all eligible U.S. employees under Section 401(k) of the Internal Revenue Code. Employees can designate the investment of their 401(k) accounts into several mutual funds. Effective January 1, 2021, the Company implemented a matching policy under which the Company matches 50 % of an employee’s contributions to the 401(k) plan, up to a maximum of 6 % of the employee’s base salary and bonus paid during the year. For the year ended December 31, 2021 the Company made employer contributions to the 401(k) plan totaling $ 221 thousand. The Company did no t make any employer contributions to the 401(k) plan during the year ended December 31, 2020 .

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2021
Related Party Transactions [Abstract]
Related Party Transactions	12. Related Party Transactions On May 6, 2021, the Company entered into an amended and restated consulting agreement (the “Consulting Agreement”) with Danforth Advisors, LLC (“Danforth”), pursuant to which Danforth, in addition to providing finance, accounting and administrative functions, provides interim chief financial officer services provided to the Company by Stephen J. DiPalma, managing director of Danforth. The Company pays Danforth an agreed upon hourly rate for such services and reimburses Danforth for expenses. The Consulting Agreement may be terminated by the Company or Danforth with cause, upon 30 days prior written notice, and without cause, upon 60 days prior written notice. As of December 31, 2021, the Company has paid Danforth approximately $ 0.4 million. In addition, on May 17, 2021, the Company has also granted Mr. DiPalma an option to purchase 15,000 shares of the Company’s common stock (the “Option”) under the Company’s 2020 Stock Incentive Plan at an exercise price of $ 15.90 . The shares underlying the Option vested as to 50 % of the shares underlying the Option on the date that is 180 days following the grant date and will vest as to the remaining 50 % of the shares underlying the Option on the first anniversary of the grant date, provided that Mr. DiPalma is providing the Services to the Company on such vesting date.

Acquisition of Assets

Acquisition of Assets	12 Months Ended
	Dec. 31, 2021
Business Combinations [Abstract]
Acquisition of Assets	13. Acquisition of Assets In July 2020 , the Company entered into an intellectual property asset purchase agreement with Alexion pursuant to which Alexion sold and assigned to the Company its right, title and interest in and to specified patent rights and other specified assets solely related to ENPP1. The Company issued 8,294,360 shares of its Series A-2 Convertible Preferred Stock to Alexion in consideration for the sale and assignment to the Company of such assets, with an estimated fair value of $ 17.8 million. The Company does not have any future payment obligations, contingent or otherwise, to Alexion in connection with this transaction. In addition, subject to certain specified qualifications set forth in the intellectual property asset purchase agreement, Alexion is obligated to assign to the Company its rights with respect to any other assets owned by it that are solely related to ENPP1. The Company concluded that this transaction constituted a purchase of intellectual property assets and not a business combination. The Company will use these assets in research and development activities and believes they have no alternative future uses. Accordingly, the Company recognized expense of $ 17.9 million as a component of research and development expense in the year ended December 31, 2020, representing the value of the intellectual property assets acquired from Alexion and related acquisition costs as of the acquisition date.

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 accompanying consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Update (“ASU”) of the Financial Accounting Standards Board (“FASB”).
Principles of Consolidation	Principles of Consolidation The accompanying consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries, Inozyme Securities Corp., which is a Massachusetts subsidiary created to buy, sell, and hold securities, Inozyme Ireland Limited, and Inozyme Pharma Switzerland GmbH. All intercompany transactions and balances have been eliminated.
Use of Estimates	Use of Estimates The preparation of the Company’s financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. Estimates and judgments are based on historical information and other market-specific or various relevant assumptions, including, in certain circumstances, future projections that management believes to be reasonable under the circumstances. Actual results could differ materially from estimates. Significant estimates and assumptions are used for, but not limited to the accruals for research and development expenses, the fair value of equity instruments issued prior to the IPO, and the grant date fair value of stock-based awards. For equity instruments issued prior to the completion of the Company’s IPO, the Company utilized various valuation methodologies in accordance with the framework of the 2013 American Institute of Certified Public Accountants Technical Practice Aid, Valuation of Privately-Held Company Equity Securities Issued as Compensation , to estimate the fair value of its equity instruments. The Company evaluates its estimates and assumptions on an ongoing basis. All revisions to accounting estimates are recognized in the period in which the estimates are revised and in any future periods affected.
Concentration of Credit Risk and Off-Balance Sheet Risk	Concentration of Credit Risk and Off-Balance Sheet Risk Financial instruments that potentially subject the Company to significant concentrations of credit risk consist primarily of cash, cash equivalents and short-term investments and, from time to time, long-term investments. The Company maintains deposits in federally insured financial institutions in excess of federally insured limits and limits its exposure to credit risk by placing its cash with high credit quality financial institutions. The Company’s investments are comprised of U.S. Treasury and U.S. government agency debt securities and commercial paper of corporations. The Company mitigates credit risk by maintaining a diversified portfolio and limiting the amount of investment exposure as to institution, maturity and investment type. The Company has no significant off-balance sheet risk such as foreign exchange contracts, option contracts, or other foreign hedging arrangements.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid investments with original maturities of three months or less at the date of purchase to be cash equivalents. Cash and cash equivalents include cash in readily available checking accounts, money market accounts and certain marketable securities. Cash is carried at cost, which approximates its fair value. Cash equivalents are carried at fair market value.
Restricted Cash	Restricted Cash Restricted cash is composed of amounts held to collateralize the letter of credit related to the Company’s lease arrangements. Restricted cash is classified as either current or non-current based on the terms of the underlying lease arrangement.
Short-Term and Long-Term Investments	Short-Term and Long-Term Investments The Company classifies its investments as available-for-sale and records such assets at estimated fair value on the balance sheet, with unrealized gains and losses on marketable securities, if any, reported as a component of accumulated other comprehensive income (loss). Realized gains and losses are calculated based on the specific-identification method and are recorded as a component of interest income. There have been no realized gains and losses for the years ended December 31, 2021 and 2020 . The Company periodically reviews available-for-sale securities for other-than-temporary declines in fair value below the cost basis whenever events or changes in circumstances indicate the carrying amount of an asset may not be recoverable. Marketable securities with a maturity date of one year or less from the balance sheet date are classified by the Company as short-term investments. Marketable securities with a maturity date of greater than one year from the balance sheet date are classified as long-term investments and are available to fund operations as needed. As of December 31, 2021, the Company did no t have any long-term investments. In accordance with the Company’s investment policy, at the time of purchase, the final maturity of each security within the portfolio shall not exceed 18 months and the weighted average maturity of the portfolio will be no greater than 12 months.
Property and Equipment	Property and Equipment Property and equipment are stated at cost, less accumulated depreciation. Depreciation is calculated using the straight-line method over the estimated useful lives of the assets. Leasehold improvements are amortized over the shorter of the lease term or the estimated useful life of the related asset. The estimated useful lives of the Company’s property and equipment are as follows: Estimated Useful Life (In Years) Laboratory equipment and manufacturing equipment 5 Furniture and fixtures 5 Computer equipment and software 3 Leasehold improvements Lesser of asset life or lease term
Impairment of Long-lived Assets	Impairment of Long-lived Assets As required under the applicable accounting guidance, the Company periodically reevaluates the original assumptions and rationale used in the establishment of the carrying value and estimated lives of all of its long-lived assets, including property and equipment. The Company reviews long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of the assets may not be recoverable. An impairment loss is recognized when the total of estimated future undiscounted cash flows, expected to result from the use of the asset and its eventual disposition, are less than its carrying amount. Impairment, if any, would be assessed using discounted cash flows or other appropriate measures of fair value. There were no impairments for the years ended December 31, 2021 and 2020 .
Accrued Research and Development Costs	Accrued Research and Development Costs The Company records accrued liabilities for estimated costs of research and development activities conducted by service providers for sponsored research, preclinical studies, clinical operations, and contract manufacturing activities. The Company records the estimated costs of research and development activities based upon the estimated amount of services provided but not yet invoiced and includes these costs in accrued expenses in the accompanying consolidated balance sheets and within research and development expense in the accompanying consolidated statements of operations and comprehensive loss. The Company accrues for these costs based on factors such as estimates of the work completed and in accordance with agreements established with service providers. The Company makes significant judgments and estimates in determining the accrued liabilities balance in each reporting period. As actual costs become known, the Company adjusts its accrued liabilities. The Company has not experienced any material differences between accrued costs and actual costs incurred since its inception.
Research and Development Costs	Research and Development Costs Research and development costs are expensed as incurred. Research and development costs consist of direct and indirect internal costs related to specific projects as well as fees paid to other entities that conduct certain research and development activities on the Company’s behalf. Research and development costs also include the write-off of acquired in-process research and development assets with no future use.
Patent Costs	Patent Costs The Company expenses all costs as incurred in connection with patent applications, including direct application fees, and the legal and consulting expenses related to making such applications, and such costs are included in general and administrative expenses within the Company’s consolidated statements of operations and comprehensive loss.
Stock-Based Compensation	Stock-Based Compensation Stock-based compensation expense represents the cost of the grant date fair value of employee and non-employee stock option grants and restricted stock awards recognized over the requisite service period of the awards on a straight-line basis. For service-based awards that are subject to graded vesting, the Company has elected to recognize compensation expense on a straight-line basis. The Company has elected to recognize forfeitures as they occur upon adoption of guidance per ASU No. 2016-09, Compensation – Stock Compensation . The Company’s equity incentive plan allows for the issuance of restricted stock awards to employees and non-employees that may be subject to vesting. The unvested shares of any restricted stock awards are held in escrow as the stock award vests or until award holder termination, whichever occurs first. In the event of a termination, the Company has the right of repurchase, at its option, the portion of unvested stock awards from the terminated award holder.
Convertible Preferred Stock	Convertible Preferred Stock The Company’s convertible preferred stock was classified as temporary equity and excluded from stockholders’ (deficit) equity as the potential redemption of such stock was outside the Company’s control. The carrying value of the convertible preferred stock was not adjusted to the redemption value until the contingent redemption events were considered to be probable of occurring. All of the Company's convertible preferred stock automatically converted to common stock in July 2020 upon completion of the Company's IPO.
IncomeTaxes	Income Taxes Income taxes have been accounted for using the asset and liability method. Under the asset and liability method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates applicable 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 the period that includes the enactment date. A valuation allowance against deferred tax assets is recorded if, based upon the weight of all available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. The Company accounts for income taxes in accordance with authoritative accounting guidance which states the impact of an uncertain income tax position is recognized at the largest amount that is “more likely than not” to be sustained upon audit by the relevant taxing authority. There are no unrecognized tax benefits included in the Company’s consolidated balance sheets at December 31, 2021 or 2020 . The Company’s policy is to recognize interest and penalties related to income tax matters in income tax expense. The Company has no t recognized any interest or penalties in its consolidated statements of operations and comprehensive loss since inception.
Leases	Leases Prior to January 1, 2021, the Company accounted for leases under Topic 840, Leases . Under Topic 840, the Company categorized leases at their inception as either operating or capital leases. On certain lease arrangements, the Company may receive rent holidays or other incentives. Prior to January 1, 2021, the Company recognized lease costs on a straight-line basis once control of the space was obtained, without regard to deferred payment terms, such as rent holidays, that defer the commencement date of required payments or escalating payment amounts. The difference between required lease payments and rent expense was recorded in accrued expenses in the accompanying consolidated balance sheets as of December 31, 2020. Additionally, incentives received were treated as a reduction of costs over the term of the agreement, as they were considered an inseparable part of the lease agreement. The Company adopted Topic 842 (as defined below) on January 1, 2021. Topic 842 allows the Company to elect a package of practical expedients, which provide that an entity need not reassess: (i) whether any expired or existing contracts are or contain leases; (ii) the lease classification for any expired or existing leases; and (iii) any initial direct costs for any existing leases. Another practical expedient allows the Company to use hindsight in determining the lease term when considering lessee options to extend or terminate the lease and to purchase the underlying asset. The Company has elected to utilize this package of practical expedients and has not elected the hindsight methodology in its implementation of Topic 842. The Company elected to adopt this standard using the optional modified retrospective approach and recognized a cumulative-effect adjustment to the consolidated balance sheet on the date of adoption. Comparative periods have not been restated. With the adoption of Topic 842, the Company’s consolidated balance sheet now contains the following line items: Right-of-use assets, Operating lease liabilities and Operating lease liabilities, net of current portion. As all the existing leases subject to Topic 842 were previously classified as operating leases by the Company, they were similarly classified as operating leases under Topic 840. The Company determines at the inception of an arrangement whether the arrangement contains a lease. If a lease is identified in an arrangement, the Company recognizes a right-of-use asset and liability on its balance sheet and determines whether the lease should be classified as a finance or operating lease. The Company does not recognize assets or liabilities for leases with original lease terms of less than 12 months. Additionally, the Company does not separate lease and non-lease components for all leases. A lease qualifies as a finance lease if any of the following criteria are met at the inception of the lease: (i) there is a transfer of ownership of the leased asset to the Company by the end of the lease term, (ii) the Company holds an option to purchase the leased asset that it is reasonably certain to exercise, (iii) the lease term is for a major part of the remaining economic life of the leased asset, (iv) the present value of the sum of lease payments equals or exceeds substantially all of the fair value of the leased asset, (v) the nature of the leased asset is specialized to the point that it is expected to provide the lessor no alternative use at the end of the lease term. All other leases are recorded as operating leases. Finance and operating lease assets and liabilities are recognized at the lease commencement date based on the present value of the lease payments over the lease term using the discount rate implicit in the lease. If the rate implicit is not readily determinable, the Company utilizes its incremental borrowing rate at the lease commencement date. Operating lease assets are further adjusted for prepaid or accrued lease payments. Operating lease payments are expensed using the straight-line method as an operating expense over the lease term. Finance lease assets are amortized to depreciation expense using the straight-line method over the shorter of the useful life of the related asset or the lease term. Finance lease payments are bifurcated into (i) a portion that is recorded as imputed interest expense and (ii) a portion that reduces the finance liability associated with the lease. The Company did no t have any finance leases recorded on its consolidated balance sheet as of December 31, 2021 and 2020 .
Deferred Issuance Costs	Deferred Issuance Costs The Company capitalizes certain legal, professional accounting and other third-party fees that are directly associated with in-process equity financings, including the Company’s IPO, as deferred issuance costs until such financings are consummated. After consummation of such an equity financing, these costs are recorded as a reduction of the proceeds generated as a result of the offering. Should a planned equity financing be abandoned, the deferred issuance costs will be expensed immediately as a charge to operating expenses in the consolidated statements of operations and comprehensive loss. The Company did no t have any deferred issuance costs recorded at December 31, 2021 or December 31, 2020 .
Net Loss Per Share	Net Loss Per Share The Company follows the two-class method when computing net loss allocable to common securities per share as the Company had previously issued shares that meet the definition of participating securities, which included shares of: (i) Series A Convertible Preferred Stock; and (ii) Series A-2 Convertible Preferred Stock. The two-class method requires a portion of net income to be allocated to the participating securities to determine net income allocable to the common securities. During periods of loss, there is no allocation required under the two-class method since the participating securities do not have a contractual obligation to fund the losses of the Company. Basic net loss per share attributable to common stockholders is computed by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period, without consideration for potentially dilutive securities. Diluted net loss per share is computed by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock and potentially dilutive securities outstanding during the period determined using the treasury-stock and if-converted methods. The Company has generated a net loss in all periods presented, therefore the basic and diluted net loss per share attributable to common stockholders are the same as the inclusion of the potentially dilutive securities would be anti-dilutive.
Segments	Segments Operating segments are defined as components of an entity for which separate financial information is available and that is regularly reviewed by the Chief Operating Decision Maker (“CODM”) in deciding how to allocate resources to an individual segment and in assessing performance. The Company’s CODM is its Chief Executive Officer. The Company has determined it operates in a single operating segment and has one reportable segment. All long-lived assets of the Company reside in the United States.
Comprehensive Income (Loss)	Comprehensive Income (Loss) The Company is required to report all components of comprehensive income (loss), including net loss, in the financial statements in the period in which they are recognized. Comprehensive income (loss) is defined as the change in equity during a period from transactions and other events and circumstances from non-owner sources. Comprehensive income (loss) is comprised of the Company’s net income (loss), unrealized gains and losses on the Company’s investments and foreign currency translation adjustment and is presented within the consolidated statements of operations and comprehensive loss.
Foreign Currency Transactions	Foreign Currency Transactions The Company maintains foreign bank accounts denominated in euros and Swiss francs. Foreign currency transactions are initially recorded by the Company using the exchange rates prevailing at the date of the transaction. At the balance sheet date, cash denominated in foreign currencies is translated at the period-end rates of exchange. Exchange gains and losses arising from the translation of foreign currency items are included in other income (expense), net in the consolidated statements of operations and comprehensive loss. The Company recognized net foreign exchange losses of $ 26 thousand and net foreign exchange gains of $ 247 thousand for the years ended December 31, 2021 and 2020 , respectively.
Fair Value Measurements	Fair Value Measurements The Company categorizes its assets and liabilities measured at fair value in accordance with the authoritative accounting guidance that establishes a consistent framework for measuring fair value, and expands disclosures for each major asset and liability category measured at fair value on either a recurring or nonrecurring basis. Fair value is defined as the exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. As a basis for considering such assumptions, the guidance establishes a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value as follows: • Level 1- Unadjusted quoted prices in active markets that are accessible at the measurement date for identical assets or liabilities; • Level 2- Quoted prices for similar assets and liabilities in active markets, quoted prices in markets that are not active, or inputs which are observable, either directly or indirectly, for substantially the full term of the asset or liability; or • Level 3- Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e., supported by little or no market activity).
Emerging Growth Company Status	Emerging Growth Company Status The Company is an “emerging growth company” (“EGC”) as defined in the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”), and the Company may take advantage of certain exemptions from various reporting requirements that are applicable to other public companies that are not EGCs. As an EGC, the Company can elect to take advantage of the extended transition period afforded by the JOBS Act for the implementation of new or revised accounting standards. The Company has elected to use the extended transition period for complying with new or revised accounting standards, and as a result of this election, the Company’s consolidated financial statements may not be comparable to companies that comply with public company FASB standards’ effective dates. The Company will remain an EGC until December 31, 2025, although if the market value of the Company’s common stock that is held by non-affiliates exceeds $ 700 million as of any June 30 before that time or if the Company has annual gross revenues of $ 1.07 billion or more in any fiscal year, the Company would cease to be an EGC as of December 31 of the applicable year. The Company would also cease to be an EGC if it issued more than $ 1 billion of non-convertible debt over a three-year period.
Recently Issued and Adopted Accounting Standards	Recently Issued and Adopted Accounting Standards In February 2016, the FASB issued ASU 2016-02, Leases (“Topic 842”) . The new standard, as amended, establishes a right-of-use model and requires a lessee to recognize on the balance sheet a right-of-use asset and corresponding lease liability for all leases with terms longer than 12 months. Leases will be classified as either finance or operating, with classification affecting the pattern of expense recognition in the consolidated statements of operations and comprehensive loss. As a result of the FASB’s issuance of ASU No. 2020-05, “Revenue From Contracts With Customers (Topic 606) and Leases (Topic 842): Effective Dates for Certain Entities”, the new standard is effective for annual periods beginning after December 15, 2021 for nonpublic entities, with early adoption permitted. On January 1, 2021 , the Company early adopted Topic 842 using the modified retrospective approach. The Company recorded operating lease assets (right-of-use assets) of $ 2.4 million and operating lease liabilities of $ 4.0 million and reversed a lease liability of $ 1.6 million related to straight-line rent and incentives. There was no impact to accumulated deficit upon adoption of Topic 842 and comparative periods have been accounted for under Topic 840. The underlying assets of the Company’s leases are primarily office and laboratory space. In August 2018, the FASB issued ASU 2018-15, Intangibles-Goodwill and Other-Internal Use Software: Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract (“ASU 2018-15”). ASU 2018-15 aligns the requirements for capitalizing implementation costs incurred in a cloud computing arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. The accounting for the service element of a hosting arrangement that is a service contract is not affected by these amendments. On January 1, 2021 , the Company adopted this standard and the adoption did not have a material impact on its consolidated financial statements.
Recently Issued Accounting Standards Not Yet Adopted	Recently Issued Accounting Standards Not Yet Adopted In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments-Credit Losses (“Topic 326”): Measurement of Credit Losses on Financial Instruments (“ASU 2016-13”) . ASU 2016-13 and its subsequent related updates establish a new forward-looking “expected loss model” that requires entities to estimate current expected credit losses on accounts receivable and financial instruments by using all practical and relevant information. The new standard and its subsequent related updates are effective for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years, with early adoption permitted. The Company is currently assessing the impact that adopting this standard will have on its consolidated financial statements but does not expect it to be material. In December 2019, the FASB issued ASU 2019-12, Income Taxes – Simplifying the Accounting for Income Taxes . The new guidance simplifies the accounting for income taxes by removing several exceptions in the current standard and adding guidance to reduce complexity in certain areas, such as requiring that an entity reflect the effect of an enacted change in tax laws or rates in the annual effective tax rate computation in the interim period that includes the enactment date. The new standard is effective for fiscal years beginning after December 15, 2021, and interim periods within fiscal years beginning after December 15, 2022 for all non-public entities, with early adoption permitted. The adoption of ASU 2019-12 is not expected to have a material impact on the Company’s consolidated financial statements.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Schedule of Estimated Useful Lives of Property and Equipment	The estimated useful lives of the Company’s property and equipment are as follows: Estimated Useful Life (In Years) Laboratory equipment and manufacturing equipment 5 Furniture and fixtures 5 Computer equipment and software 3 Leasehold improvements Lesser of asset life or lease term

Balance Sheet Details (Tables)

Balance Sheet Details (Tables)	12 Months Ended
	Dec. 31, 2021
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Schedule of Short-Term Investments	Short-term investments consisted of the following (dollar amounts in thousands): December 31, 2021 Description Maturity Amortized Gross Gross Estimated Commercial paper 1 year or less $ 78,456 $ 5 $ ( 3 ) $ 78,458 U.S. Treasury securities 1 year or less 5,025 — — 5,025 U.S. government agency debt securities 1 year or less 5,002 — — 5,002 $ 88,483 $ 5 $ ( 3 ) $ 88,485 December 31, 2020 Description Maturity Amortized Gross Gross Estimated Commercial paper 1 year or less $ 94,873 $ 5 $ ( 6 ) $ 94,872 U.S. Treasury securities 1 year or less 11,614 2 ( 1 ) 11,615 U.S. government agency debt securities 1 year or less 13,169 1 — 13,170 $ 119,656 $ 8 $ ( 7 ) $ 119,657
Schedule of Prepaid Expenses and Other Current Assets	Prepaid expenses and other current assets consisted of the following (dollar amounts in thousands): At December 31, 2021 At December 31, 2020 Interest receivable $ 62 $ 155 Prepaid insurance 1,728 1,723 Prepaid research studies 1,190 804 Prepaid other 561 600 Total $ 3,541 $ 3,282
Schedule of Noncurrent Prepaid Expenses	Noncurrent prepaid expenses consisted of the following (dollar amounts in thousands): At December 31, 2021 At December 31, 2020 Prepaid clinical trial and other $ 3,409 $ 3,183 $ 3,409 $ 3,183
Schedule of Property and Equipment	Property and equipment consisted of the following (dollar amounts in thousands): At December 31, 2021 At December 31, 2020 Laboratory equipment and manufacturing equipment $ 591 $ 339 Furniture and fixtures 258 254 Computer equipment and software 440 287 Leasehold improvements 2,095 2,095 3,384 2,975 Less accumulated depreciation ( 1,001 ) ( 327 ) Total $ 2,383 $ 2,648
Schedule of Accrued Expenses	Accrued expenses consisted of the following (dollar amounts in thousands): At December 31, 2021 At December 31, 2020 Payroll and related liabilities $ 2,379 $ 2,296 Professional fees 727 454 Research and development costs 5,066 2,997 Deferred rent — 279 Other 336 878 Total $ 8,508 $ 6,904

Fair Value Measurement (Tables)

Fair Value Measurement (Tables)	12 Months Ended
	Dec. 31, 2021
Fair Value Disclosures [Abstract]
Summary of Financial Assets Measured at Fair Value	The following table represents the Company’s financial assets measured at fair value on a recurring basis and indicate the level of fair value hierarchy utilized to determine such fair values (in thousands): Fair Value Measurements at Reporting Date Description December 31, 2021 Quoted Significant Significant Assets: Money market funds (included in cash and cash $ 14,302 $ 14,302 $ — $ — Commercial paper 78,457 — 78,457 — U.S. Treasury securities 5,026 5,026 — — U.S. government agency debt securities 5,002 — 5,002 — Total assets $ 102,787 $ 19,328 $ 83,459 $ — Fair Value Measurements at Reporting Date Description December 31, Quoted Significant Significant Assets: Money market funds (included in cash and cash $ 15,739 $ 15,739 $ — $ — Commercial paper 94,872 — 94,872 — U.S. Treasury securities 16,741 16,741 — — U.S. government agency debt securities 20,243 — 20,243 — Total assets $ 147,595 $ 32,480 $ 115,115 $ —

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2021
Commitments And Contingencies Disclosure [Abstract]
Schedule of Future Lease Payments Under Non-Cancelable Leases	Future lease payments under non-cancelable leases as of December 31, 2021 are as follows (dollar amounts in thousands): Year Ending December 31, 2022 $ 968 2023 992 2024 1,016 2025 944 Thereafter - $ 3,920

Convertible Preferred Stock a_2

Convertible Preferred Stock and Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2021
Summary of Stock Option Activity Under Equity Incentive Plans	The following table summarizes stock option activity under the Company’s equity incentive plans since December 31, 2020: Options Weighted- Weighted- Aggregate (in years) (in thousands) Outstanding at December 31, 2020 3,064,457 $ 7.28 8.76 $ 41,680 Granted 1,314,504 17.16 Exercised ( 283,778 ) 2.15 Forfeited ( 512,570 ) 12.05 Outstanding at December 31, 2021 3,582,613 $ 10.63 8.32 $ 7,428 Exercisable at December 31, 2021 1,427,662 $ 7.09 7.55 $ 4,816 Vested and expected to vest at December 31, 2021 3,582,613 $ 10.63 8.32 $ 7,428
Employees
Summary of Assumptions Used to Value Stock Options Granted Using Black-Scholes Option-Pricing	The underlying assumptions used to value stock options granted to participants using the Black-Scholes option-pricing were as follows: Years Ended December 31, 2021 2020 Risk-free interest rate range 0.48 % to 1.37 % 0.36 % to 0.55 % Dividend yield 0 % 0 % Expected term of options (years) 5.37 to 6.48 6.08 to 6.78 Volatility rate range 88.41 % to 91.19 % 86.54 % to 99.85 %

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Schedule of Reconciliation of U.S. Federal Statutory Income Tax Rate to Effective Income Tax Rate	A reconciliation of the U.S. federal statutory income tax rate to the Company’s effective income tax rate is as follows: Year Ended December 31, 2021 2020 Federal income tax at statutory rate 21.0 % 21.0 % Permanent differences ( 1.6 ) ( 0.5 ) State income tax, net of federal benefit 5.4 5.0 Federal and state research and development tax credits 6.8 0.9 Valuation allowance ( 31.6 ) ( 26.4 ) Effective income tax rate — % — %
Significant Components of Deferred Tax Assets	The significant components of the Company’s deferred tax assets as of December 31, 2021 and 2020 are comprised of the following (dollar amounts in thousands): December 31, 2021 2020 Deferred tax assets: Net operating losses $ 31,110 $ 17,712 Research and development credits 5,268 1,007 Stock options 833 157 Accrued expenses 490 594 Deferred rent — 408 Amortization 4,194 4,520 Lease liability 875 — Other 96 173 Gross deferred tax assets 42,866 24,571 Less: Valuation allowance ( 42,056 ) ( 24,199 ) Net deferred tax assets 810 372 Deferred tax liabilities: Depreciation of fixed assets ( 277 ) ( 372 ) Right of use assets ( 533 ) — Gross deferred tax liabilities ( 810 ) ( 372 ) Non-current net deferred tax assets (liabilities) $ — $ —

Net Loss per Share (Tables)

Net Loss per Share (Tables)	12 Months Ended
	Dec. 31, 2021
Earnings Per Share [Abstract]
Schedule of Potential Dilutive Securities from Computation of Diluted Net Loss Per Share Attributable to Common Stockholders	The Company excluded the following potential dilutive securities, presented based on amounts outstanding at December 31, 2021 and 2020, from the computation of diluted net loss per share attributable to common stockholders because including them would have had an anti-dilutive effect: Year Ended December 31, 2021 2020 Options to purchase common stock 3,582,613 3,064,457 3,582,613 3,064,457

Organization and Basis of Pre_2

Organization and Basis of Presentation - Additional Information (Details) $ / shares in Units, $ in Thousands	Jul. 30, 2020USD ($)shares	Jul. 28, 2020$ / sharesshares	Jul. 17, 2020	Dec. 31, 2021USD ($)	Dec. 31, 2020USD ($)
Subsidiary, Sale of Stock [Line Items]
Reverse stock split of common stock			0.1338
Stockholders' equity, reverse stock split			one-for-7.4730 reverse stock split
Net proceeds issuance of common stock, deducting underwriting discounts and commissions | $	$ 115,900
Number of outstanding preferred stock converted | shares		104,277,222
Number of common stock issued upon conversion | shares		13,953,850
Net loss | $				$ 56,624	$ 56,424
Accumulated deficit | $				147,700	91,076
Cash and cash equivalents and short term investments | $				$ 111,800	$ 159,900
I P O [Member]
Subsidiary, Sale of Stock [Line Items]
Shares issued | shares		7,000,000
Shares issued, price per shares | $ / shares		$ 16
Over-Allotment Option [Member]
Subsidiary, Sale of Stock [Line Items]
Shares issued | shares	1,050,000

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Additional Information (Details)	12 Months Ended
	Dec. 31, 2021USD ($)Segment	Dec. 31, 2020USD ($)	Jun. 30, 2021USD ($)
Off-balance sheet concentrations of credit risk description	The Company has no significant off-balance sheet risk such as foreign exchange contracts, option contracts, or other foreign hedging arrangements.
Off-balance sheet concentrations of credit risk	$ 0	$ 0
Realized gain and losses on investments as available-for-sale	0	0
Impairments of long-lived assets	0	0
Unrecognized tax benefits	$ 0	0
Number of operating segments | Segment	1
Number of reportable segments | Segment	1
Net foreign exchange gain (loss)	$ (26,000)	247,000
Issuance period of non-convertible debt cease to be EGC	3 years
Long-term investments	$ 0	12,199,000
Debt securities held-to-maturity	12 months
Income tax penalties and interest expense	$ 0
Finance lease	0	0
Deferred issuance costs	0	$ 0
Minimum
Market value of common stock held by non-affiliates cease to be EGC			$ 700,000,000
Annual gross revenues cease to be EGC	1,070,000,000
Issuance of non-convertible debt cease to be EGC	$ 1,000,000,000
Maximum
Debt securities held-to-maturity	18 months

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Schedule of Estimated Useful Lives of Property and Equipment (Details)	12 Months Ended
	Dec. 31, 2021
Laboratory Equipment and Manufacturing Equipment
Property Plant And Equipment [Line Items]
Estimated Useful Life (In Years)	5 years
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Estimated Useful Life (In Years)	5 years
Computer Equipment and Software
Property Plant And Equipment [Line Items]
Estimated Useful Life (In Years)	3 years
Leasehold Improvements
Property Plant And Equipment [Line Items]
Estimated Useful Life (In Years)	Lesser of asset life or lease term

Recent Accounting Pronounceme_2

Recent Accounting Pronouncements - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Jan. 01, 2021	Dec. 31, 2020
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Change in accounting principle, accounting standards update, adopted	true
Right-of-use assets	$ 2,053		$ 0
Accumulated deficit	$ (147,700)		$ (91,076)
Change in accounting principle, accounting standards update, immaterial effect	true
Accounting Standards Update [Extensible Enumeration]	us-gaap:AccountingStandardsUpdate201813Member
ASU 2016-02
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Change in accounting principle, accounting standards update, adoption date	Jan. 1, 2021	Jan. 1, 2021
Change in accounting principle, accounting standards update, adopted		true
Right-of-use assets		$ 2,400
Operating lease liabilities		4,000
Operating lease, reversed lease liability		1,600
ASU 2016-02 | Revision of Prior Period, Accounting Standards Update, Adjustment
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Accumulated deficit		$ 0

Balance Sheet Details - Schedul

Balance Sheet Details - Schedule of Short-Term Investments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Schedule Of Available For Sale Securities [Line Items]
Amortized Costs	$ 88,483	$ 119,656
Gross Unrealized Gains	5	8
Gross Unrealized Losses	(3)	(7)
Estimated Fair Value	$ 88,485	119,657
Long Term Investments
Schedule Of Available For Sale Securities [Line Items]
Amortized Costs		12,198
Gross Unrealized Gains		1
Gross Unrealized Losses		0
Estimated Fair Value		$ 12,199
Commercial Paper
Schedule Of Available For Sale Securities [Line Items]
Maturity	1 year or less	1 year or less
Amortized Costs	$ 78,456	$ 94,873
Gross Unrealized Gains	5	5
Gross Unrealized Losses	(3)	(6)
Estimated Fair Value	$ 78,458	$ 94,872
U.S. Treasury Securities
Schedule Of Available For Sale Securities [Line Items]
Maturity	1 year or less	1 year or less
Amortized Costs	$ 5,025	$ 11,614
Gross Unrealized Gains	0	2
Gross Unrealized Losses	0	(1)
Estimated Fair Value	$ 5,025	$ 11,615
U.S. Treasury Securities | Long Term Investments
Schedule Of Available For Sale Securities [Line Items]
Maturity		After 1 year through 5 years
Amortized Costs		$ 5,126
Gross Unrealized Gains		0
Gross Unrealized Losses		0
Estimated Fair Value		$ 5,126
U.S. Government Agency Debt Securities
Schedule Of Available For Sale Securities [Line Items]
Maturity	1 year or less	1 year or less
Amortized Costs	$ 5,002	$ 13,169
Gross Unrealized Gains	0	1
Gross Unrealized Losses	0	0
Estimated Fair Value	$ 5,002	$ 13,170
U.S. Government Agency Debt Securities | Long Term Investments
Schedule Of Available For Sale Securities [Line Items]
Maturity		After 1 year through 5 years
Amortized Costs		$ 7,072
Gross Unrealized Gains		1
Gross Unrealized Losses		0
Estimated Fair Value		$ 7,073

Balance Sheet Details - Additio

Balance Sheet Details - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Long-term investments	$ 0	$ 12,199
Depreciation expense	$ 674	$ 217

Balance Sheet Details - Sched_2

Balance Sheet Details - Schedule of Long-Term Investments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Schedule Of Available For Sale Securities [Line Items]
Amortized Costs	$ 88,483	$ 119,656
Gross Unrealized Gains	5	8
Gross Unrealized Losses	(3)	(7)
Estimated Fair Value	$ 88,485	$ 119,657
U.S. Treasury Securities
Schedule Of Available For Sale Securities [Line Items]
Maturity	1 year or less	1 year or less
Amortized Costs	$ 5,025	$ 11,614
Gross Unrealized Gains	0	2
Gross Unrealized Losses	0	(1)
Estimated Fair Value	$ 5,025	$ 11,615
U.S. Government Agency Debt Securities
Schedule Of Available For Sale Securities [Line Items]
Maturity	1 year or less	1 year or less
Amortized Costs	$ 5,002	$ 13,169
Gross Unrealized Gains	0	1
Gross Unrealized Losses	0	0
Estimated Fair Value	$ 5,002	13,170
Long Term Investments
Schedule Of Available For Sale Securities [Line Items]
Amortized Costs		12,198
Gross Unrealized Gains		1
Gross Unrealized Losses		0
Estimated Fair Value		$ 12,199
Long Term Investments | U.S. Treasury Securities
Schedule Of Available For Sale Securities [Line Items]
Maturity		After 1 year through 5 years
Amortized Costs		$ 5,126
Gross Unrealized Gains		0
Gross Unrealized Losses		0
Estimated Fair Value		$ 5,126
Long Term Investments | U.S. Government Agency Debt Securities
Schedule Of Available For Sale Securities [Line Items]
Maturity		After 1 year through 5 years
Amortized Costs		$ 7,072
Gross Unrealized Gains		1
Gross Unrealized Losses		0
Estimated Fair Value		$ 7,073

Balance Sheet Details - Sched_3

Balance Sheet Details - Schedule of Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
Interest receivable	$ 62	$ 155
Prepaid insurance	1,728	1,723
Prepaid research studies	1,190	804
Prepaid other	561	600
Total	$ 3,541	$ 3,282

Balance Sheet Details - Sched_4

Balance Sheet Details - Schedule of Noncurrent Prepaid Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Payables And Accruals [Abstract]
Prepaid clinical trial and other	$ 3,409	$ 3,183
Prepaid expenses - noncurrent	$ 3,409	$ 3,183

Balance Sheet Details - Sched_5

Balance Sheet Details - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 3,384	$ 2,975
Less accumulated depreciation	(1,001)	(327)
Total	2,383	2,648
Laboratory Equipment and Manufacturing Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	591	339
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Property and equipment, gross	258	254
Computer Equipment and Software
Property Plant And Equipment [Line Items]
Property and equipment, gross	440	287
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 2,095	$ 2,095

Balance Sheet Details - Sched_6

Balance Sheet Details - Schedule of Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Payables And Accruals [Abstract]
Payroll and related liabilities	$ 2,379	$ 2,296
Professional fees	727	454
Research and development costs	5,066	2,997
Deferred rent	0	279
Other	336	878
Total	$ 8,508	$ 6,904

Fair Value Measurement - Summar

Fair Value Measurement - Summary of Financial Assets Measured at Fair Value (Details) - Recurring - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value disclosure	$ 102,787	$ 147,595
Money Market Funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents fair value disclosure	14,302	15,739
Commercial Paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value disclosure	78,457	94,872
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value disclosure	19,328	32,480
Quoted Prices in Active Markets for Identical Assets (Level 1) | Money Market Funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents fair value disclosure	14,302	15,739
Quoted Prices in Active Markets for Identical Assets (Level 1) | Commercial Paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value disclosure
Significant Other Observable Inputs (Level 2)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value disclosure	83,459	115,115
Significant Other Observable Inputs (Level 2) | Money Market Funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents fair value disclosure	0	0
Significant Other Observable Inputs (Level 2) | Commercial Paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value disclosure	78,457	94,872
Significant Unobservable Inputs (Level 3)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value disclosure	0
Significant Unobservable Inputs (Level 3) | Money Market Funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents fair value disclosure	0	0
Significant Unobservable Inputs (Level 3) | Commercial Paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value disclosure
U.S. Treasury Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value disclosure	5,026	16,741
U.S. Treasury Securities | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value disclosure	5,026	16,741
U.S. Treasury Securities | Significant Other Observable Inputs (Level 2)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value disclosure
U.S. Treasury Securities | Significant Unobservable Inputs (Level 3)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value disclosure
U.S. Government Agency Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value disclosure	5,002	20,243
U.S. Government Agency Debt Securities | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value disclosure
U.S. Government Agency Debt Securities | Significant Other Observable Inputs (Level 2)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value disclosure	5,002	20,243
U.S. Government Agency Debt Securities | Significant Unobservable Inputs (Level 3)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value disclosure

Fair Value Measurement - Additi

Fair Value Measurement - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Fair value assets level 1 to level 2 transfers amount	$ 0	$ 0
Fair value assets level 2 to level 1 transfers amount	0	0
Fair value measurement with unobservable inputs reconciliation recurring basis asset transfers into level 3	0	0
Fair value measurement with unobservable inputs reconciliation recurring basis asset transfers out of level 3	$ 0	$ 0

License and Sponsored Researc_2

License and Sponsored Research Agreements - Additional Information (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Feb. 28, 2019	Dec. 31, 2021	Dec. 31, 2020
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Research support funding expiration year	2021-12
Research and development expenses		$ 37,720	$ 46,493
Sponsored Research Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Research support funding contract extended date	Jun. 30, 2022
Yale
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Partial upfront consideration payment under license agreement		60
Yale | Net Product Sales Milestone [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone payment upon achievement of certain milestones		3,000
Yale | First Patient in Company Milestones [Member]
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone payment upon achievement of certain milestones		250
Yale | Sponsored Research Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Research support funding amount	$ 2,400
Research support funding period	5 years
Research and development expenses		500	400
Yale | License
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Maintenance fees		$ 100	$ 44

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details)	Jan. 01, 2021USD ($)ft²	Dec. 31, 2021USD ($)	Dec. 31, 2020USD ($)
Lessee Lease Description [Line Items]
Change in accounting principle, accounting standards update, adopted		true
Weighted average incremental borrowing rate for operating leases	8.00%	8.00%
Weighted average remaining lease term for operating leases	5 years	3 years 10 months 24 days
Right-of-use assets		$ 2,053,000	$ 0
Cash paid for amounts included for measurement of lease liabilities		900,000	600,000
Operating lease expense		700,000	700,000
Costs related to legal proceedings		0	0
Restricted Cash | Letters of Credit
Lessee Lease Description [Line Items]
Security deposits		$ 354,000	$ 354,000
Office Space | Boston, Massachusetts
Lessee Lease Description [Line Items]
Area of leased space | ft²	8,499
Lessee operating lease expiration year	2025
Lessee, Operating Lease, Existence of Option to Extend [true false]	true
Lessee operating lease option to extend description		option to extend the term for five years
Operating lease renewal term	5 years
Laboratory Space | Boston, Massachusetts
Lessee Lease Description [Line Items]
Area of leased space | ft²	6,244
Lessee operating lease expiration year	2025
ASU 2016-02
Lessee Lease Description [Line Items]
Change in accounting principle, accounting standards update, adopted	true
Change in accounting principle, accounting standards update, adoption date	Jan. 1, 2021	Jan. 1, 2021
Right-of-use assets	$ 2,400,000
Operating lease liabilities	$ 4,000,000

Commitments and Contingencies_2

Commitments and Contingencies - Schedule of Future Lease Payments Under Non-Cancelable Leases (Details) $ in Thousands	Dec. 31, 2021USD ($)
Commitments And Contingencies Disclosure [Abstract]
2022	$ 968
2023	992
2024	1,016
2025	944
Thereafter	0
Operating lease liability	$ 3,920

Convertible Preferred Stock a_3

Convertible Preferred Stock and Stockholders' Equity - Additional Information (Details) - USD ($)	May 17, 2021	Jul. 23, 2020	Jun. 30, 2020	Mar. 31, 2019	Nov. 30, 2018	Jan. 01, 2017	Dec. 31, 2021	Dec. 31, 2020	Jan. 01, 2022	Aug. 11, 2021	Jan. 01, 2021	Jul. 31, 2020	Jul. 28, 2020	Jul. 17, 2020	Jan. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Net proceeds from issuance of shares							$ 0	$ 33,638,000
Preferred stock, shares outstanding							0	0
Number of outstanding preferred stock converted into common stock													13,953,850
Common stock, shares authorized							200,000,000	200,000,000					200,000,000
Preferred stock, shares authorized							5,000,000	5,000,000					5,000,000
Dividends declared on preferred stock or common stock							$ 0
Plan description							On July 17, 2020, the Company’s stockholders approved the 2020 Stock Incentive Plan (the “2020 Plan”), which became effective on July 23, 2020. The 2020 Plan provides for the grant of incentive stock options, non-statutory stock options, stock appreciation rights, restricted stock awards, restricted stock units and other stock-based awards. The number of shares of the Company’s common stock reserved for issuance under the 2020 Plan
Granted options	15,000						1,314,504
Weighted-average exercise price of options granted	$ 15.90						$ 17.16
Weighted-average grant date fair value of options granted							$ 12.86	$ 9.15
Aggregate intrinsic value of stock options exercised							$ 3,000,000	$ 700,000
Total unrecognized compensation cost related to outstanding employee awards							$ 19,300,000
Total unrecognized compensation cost related to outstanding employee awards, expected to be recognized over a weighted-average period							2 years 9 months 18 days
Share based compensation options to purchase number of common stock							3,582,613	3,064,457
Fair value of shares vested							$ 6,500,000	$ 1,300,000
Share Based Payment Arrangement Employee [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense							5,500,000	1,800,000
Share-based Payment Arrangement, Nonemployee [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense							$ 1,600,000	$ 500,000
2020 Stock Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for issuance		1,588,315					904,016		946,749		935,398
Number of common stock reserved for issuance increase percentage on stock outstanding		4.00%
2017 Stock Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for issuance		426,065
2017 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares authorized for issuance												2,730,496
Number of awards available for issuance														0
2020 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for issuance									236,687		233,849
Number of common stock reserved for issuance increase percentage on stock outstanding		1.00%
Plan description		The number of shares of common stock reserved for issuance under the ESPP will automatically increase on January 1, 2021 and each January 1 thereafter through January 1, 2031, in an amount equal to the lowest of (1) 397,079 shares of the Company’s common stock, (2) 1% of the number of shares of the Company’s common stock outstanding on the first day of such fiscal year and (3) an amount determined by the Company’s board of directors.
Share based compensation options to purchase number of common stock		198,539
Increase in additional number of shares to be issued		397,079
Number of shares purchased							0
IPO
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Preferred stock, shares outstanding													104,277,222
Maximum | Jefferies LLC
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Offer and sell										$ 200,000,000
Aggregate offering price										$ 50,000,000
Series A Convertible Preferred Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Convertible preferred stock, shares issued															27,083,333
Shares issued, price per share					$ 1										$ 1
Net proceeds from issuance of shares					$ 21,600,000	$ 26,700,000
Shares available for issuance to investors															21,666,667
Shares available for issuance, price per share															$ 1
Additional shares issued					21,666,667
Series A Convertible Preferred Stock [Member] | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Convertible preferred stock, shares issued															100,000
Convertible preferred stock, shares authorized															48,750,000
Series A-2 Convertible Preferred Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Convertible preferred stock, shares issued				16,083,916	7,482,515
Shares issued, price per share			$ 1.43	$ 1.43	$ 1.43
Net proceeds from issuance of shares			$ 33,600,000	$ 22,900,000	$ 10,400,000
Shares available for issuance to investors				23,566,431
Shares available for issuance, price per share				$ 1.43
Additional shares issued			23,566,431
Series A-2 Convertible Preferred Stock [Member] | Alexion Pharmaceuticals, Inc
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Convertible preferred stock, shares issued												8,294,360
Additional shares issued												8,294,360
Series A-2 Convertible Preferred Stock [Member] | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Convertible preferred stock, shares issued					47,132,862
Convertible preferred stock, shares authorized												55,427,222
Series A-2 Convertible Preferred Stock [Member] | Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Convertible preferred stock, shares authorized					47,132,862

Convertible Preferred Stock a_4

Convertible Preferred Stock and Stockholders' Equity - Summary of Stock Option Activity Under Equity Incentive Plans (Details) - USD ($) $ / shares in Units, $ in Thousands	May 17, 2021	Dec. 31, 2021	Dec. 31, 2020
Convertible Preferred Stock And Stockholders Equity [Abstract]
Options Outstanding, Beginning Balance		3,064,457
Options Outstanding, Granted	15,000	1,314,504
Options Outstanding, Exercised		(283,778)
Options Outstanding, Forfeited		(512,570)
Options Outstanding, Ending Balance		3,582,613	3,064,457
Options Outstanding, Exercisable		1,427,662
Options Outstanding, Vested and expected to vest		3,582,613
Weighted Average Exercise Price, Outstanding, Beginning Balance		$ 7.28
Weighted Average Exercise Price, Granted	$ 15.90	17.16
Weighted Average Exercise Price, Exercised		2.15
Weighted Average Exercise Price, Forfeited		12.05
Weighted Average Exercise Price, Outstanding, Ending Balance		10.63	$ 7.28
Weighted Average Exercise Price, Exercisable		7.09
Weighted Average Exercise Price, Vested and expected to vest		$ 10.63
Weighted Average Remaining Contractual Term (in years), Outstanding		8 years 3 months 25 days	8 years 9 months 3 days
Weighted Average Remaining Contractual Term (in years), Exercisable		7 years 6 months 18 days
Weighted Average Remaining Contractual Term (in years), Vested and expected to vest		8 years 3 months 25 days
Aggregate Intrinsic Value, Outstanding		$ 7,428	$ 41,680
Aggregate Intrinsic Value, Exercisable		4,816
Aggregate Intrinsic Value, Vested and expected to vest		$ 7,428

Convertible Preferred Stock a_5

Convertible Preferred Stock and Stockholders' Equity - Summary of Assumptions Used to Value Stock Options Granted to Employees using Black-Scholes Option-Pricing (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Risk-free interest rate range, minimum	0.48%	0.36%
Risk-free interest rate range, maximum	1.37%	0.55%
Dividend yield	0.00%	0.00%
Volatility rate range, minimum	88.41%	86.54%
Volatility rate range, maximum	91.19%	99.85%
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term of options (years)	5 years 4 months 13 days	6 years 29 days
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term of options (years)	6 years 5 months 23 days	6 years 9 months 10 days

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Mar. 27, 2020	Jan. 01, 2018
Operating Loss Carryforwards [Line Items]
Net loss	$ 56,624	$ 56,424
Income tax benefit	0	0
Deferred tax assets, valuation allowance	42,056	$ 24,199
Deferred tax assets, increase in valuation allowance	17,900
Operating loss carryforwards with no expiration period	115,700
Tax cuts and jobs act federal net operating loss			80.00%
Suspend of tax cuts and jobs act federal net operating loss due to cares act.				80.00%
Federal
Operating Loss Carryforwards [Line Items]
Gross operating loss carryforwards	121,300
Operating loss carryforwards with expiration period	$ 5,600
Operating loss carryforwards expiration year	2037
Federal | Research and Development
Operating Loss Carryforwards [Line Items]
Credit carryforward, expiration year	2037
State
Operating Loss Carryforwards [Line Items]
Gross operating loss carryforwards	$ 92,000
Operating loss carryforwards expiration year	2037
State | Research and Development
Operating Loss Carryforwards [Line Items]
Credit carryforward, expiration year	2041
Federal and State | Research and Development
Operating Loss Carryforwards [Line Items]
Credit carryforwards	$ 5,400

Income Taxes - Schedule of Reco

Income Taxes - Schedule of Reconciliation of U.S. Federal Statutory Income Tax Rate to Effective Inc (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Federal income tax at statutory rate	21.00%	21.00%
Permanent differences	(1.60%)	(0.50%)
State income tax, net of federal benefit	5.40%	5.00%
Federal and state research and development tax credits	6.80%	0.90%
Valuation allowance	(31.60%)	(26.40%)
Effective income tax rate	0.00%	0.00%

Income Taxes - Significant Comp

Income Taxes - Significant Components of Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deferred tax assets:
Net operating losses	$ 31,110	$ 17,712
Research and development credits	5,268	1,007
Stock options	833	157
Accrued expenses	490	594
Deferred rent	0	408
Amortization	4,194	4,520
Lease liability	875	0
Other	96	173
Gross deferred tax assets	42,866	24,571
Less: Valuation allowance	(42,056)	(24,199)
Net deferred tax assets	810	372
Deferred tax liabilities:
Depreciation of fixed assets	(277)	(372)
Right of use assets	(533)	0
Gross deferred tax liabilities	810	372
Non-current net deferred tax assets (liabilities)	$ 0	$ 0

Related Party Transactions (Add

Related Party Transactions (Additional Information) (Details) - USD ($) $ / shares in Units, $ in Millions	May 17, 2021	May 06, 2021	Dec. 31, 2021
Related Party Transaction [Line Items]
Management Fee Expense			$ 0.4
Options Outstanding, Granted	15,000		1,314,504
Weighted Average Exercise Price, Granted	$ 15.90		$ 17.16
Share-based Goods and Nonemployee Services Transaction, Valuation Method, Expected Dividend Rate	50.00%
Share-based Goods and Nonemployee Services Transaction, Valuation Method, Expected Term	180 days
30 Days prior written notice
Related Party Transaction [Line Items]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Notice Period		30 days
60 Days prior written notice
Related Party Transaction [Line Items]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Notice Period		60 days

Net Loss per Share - Schedule o

Net Loss per Share - Schedule of Potential Dilutive Securities from Computation of Diluted Net Loss Per Share Attributable to Common Stockholders (Details) - shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive shares excluded from computation of earnings per share	3,582,613	3,064,457
Options to Purchase Common Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive shares excluded from computation of earnings per share	3,582,613	3,064,457

Employee Benefit Plans - Additi

Employee Benefit Plans - Additional Information (Details) - USD ($) $ in Thousands	Jan. 01, 2021	Dec. 31, 2021	Dec. 31, 2020
Defined Contribution Plan Disclosure [Line Items]
Employer matching contribution, percentage of match	50.00%
Employer contribution amount		$ 221	$ 0
Maximum
Defined Contribution Plan Disclosure [Line Items]
Employer matching contribution, percentage of employees base salary and bonus paid	6.00%

Acquisition of Assets (Addition

Acquisition of Assets (Additional Information) (Details) - USD ($) $ in Millions	Jul. 30, 2020	Dec. 31, 2020	Jul. 31, 2020	Mar. 31, 2019	Nov. 30, 2018
Alexion Pharmaceuticals, Inc
Business Acquisition [Line Items]
Acquired intellectual property, research and development expenses		$ 17.9
Alexion Pharmaceuticals, Inc | Intellectual Property
Business Acquisition [Line Items]
Acquisition of intellectual property, estimated fair value	$ 17.8
Series A-2 Convertible Preferred Stock [Member]
Business Acquisition [Line Items]
Shares issued				16,083,916	7,482,515
Series A-2 Convertible Preferred Stock [Member] | Alexion Pharmaceuticals, Inc
Business Acquisition [Line Items]
Shares issued			8,294,360