Sensei Biotherapeutics (SNSE) 10-Q 10 May 22 2022 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2022	May 06, 2022
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2022
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q1
Entity Registrant Name	Sensei Biotherapeutics, Inc.
Entity Central Index Key	0001829802
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		30,628,813
Entity Shell Company	false
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Title of 12(b) Security	Common Stock, $0.0001 par value per share
Trading Symbol	SNSE
Security Exchange Name	NASDAQ
Entity File Number	001-39980
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	83-1863385
Entity Address, Address Line One	451 D Street
Entity Address, Address Line Two	Suite 710
Entity Address, City or Town	Boston
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02210
City Area Code	240
Local Phone Number	243-8000
Document Quarterly Report	true
Document Transition Report	false

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 8,721	$ 7,159
Marketable securities	127,503	140,462
Prepaid expenses	2,554	547
Other current assets	199	374
Total current assets	138,977	148,542
Right of use assets - operating leases, net	6,267
Right of use assets - financing leases, net	2,551
Property and equipment, net	2,204	4,644
Other non-current assets	39	39
Total assets	150,038	153,225
Current liabilities:
Accounts payable and accrued liabilities	5,100	2,456
Compensation and employee benefits liabilities	560	1,753
Operating lease liabilities, current	1,160
Financing lease liabilities, current	786	680
Total current liabilities	7,606	4,889
Operating lease liabilities, non-current	5,278
Financing lease liabilities, non-current	1,846	1,674
Other non-current liabilities		149
Total liabilities	14,730	6,712
Commitments and contingencies (Note 7)
Stockholders' equity:
Common stock, $0.0001 par value and 250,000,000 shares authorized as of March 31, 2022 and December 31, 2021; 30,682,813 and 30,609,029 shares issued and outstanding at March 31, 2022 and December 31, 2021, respectively	3	3
Additional paid-in capital	297,815	296,049
Accumulated deficit	(161,611)	(149,206)
Accumulated other comprehensive loss	(899)	(333)
Total stockholders' equity	135,308	146,513
Total liabilities and stockholders' equity	$ 150,038	$ 153,225

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical) - $ / shares	Mar. 31, 2022	Dec. 31, 2021
Statement Of Financial Position [Abstract]
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	250,000,000	250,000,000
Common stock, shares issued	30,682,813	30,609,029
Common stock, shares outstanding	30,682,813	30,609,029

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Operating expenses:
Research and development	$ 7,455	$ 3,365
General and administrative	5,032	4,604
Total operating expenses	12,487	7,969
Loss from operations	(12,487)	(7,969)
Other income (expense):
Realized gain on marketable securities	15
Interest income	310
Interest expense	(243)	(3)
Net loss	(12,405)	(7,972)
Net loss attributable to common stockholders	$ (12,405)	$ (7,972)
Net loss per common share, basic and diluted	$ (0.40)	$ (0.42)
Weighted-average number of shares used in computing net loss per common share, basic and diluted	30,647,679	18,904,853
Comprehensive loss:
Net loss	$ (12,405)	$ (7,972)
Other comprehensive items:
Unrealized loss on marketable securities	(566)
Total other comprehensive loss	(566)
Total comprehensive loss	$ (12,971)	$ (7,972)

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF CONVERTIBLE PREFERRED STOCK, COMMON STOCK AND STOCKHOLDERS' EQUITY (DEFICIT) (Unaudited) - USD ($) $ in Thousands	Total	Convertible Preferred Stock Series AA	Convertible Preferred Stock Series BB	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Accumulated Other Comprehensive Loss
Beginning balance at Dec. 31, 2020	$ (56,443)				$ 55,969	$ (112,412)
Temporary equity, Beginning balance, shares at Dec. 31, 2020		747,683,172	52,680,306
Temporary equity, Beginning balance at Dec. 31, 2020		$ 61,411	$ 10,925
Beginning balance, shares at Dec. 31, 2020				1,875,422
Stock-based compensation expense	1,349				1,349
Issuance of preferred stock			$ 23,491
Issuance of preferred stock, shares			113,275,902
Temporary equity, Conversion of preferred stock to common stock upon closing of the initial public offering		$ (61,411)	$ (34,416)
Temporary equity, Conversion of preferred stock to common stock upon closing of the initial public offering, shares		(747,683,172)	(165,956,208)
Conversion of preferred stock to common stock upon closing of the initial public offering	95,828			$ 2	95,826
Conversion of preferred stock to common stock upon closing of the initial public offering, shares				19,034,069
Issuance of common stock upon closing of the initial public offering, net of issuance costs	138,489			$ 1	138,488
Issuance of common stock upon closing of the initial public offering, net of issuance costs, shares				8,030,295
Exercise of common stock warrants	1				1
Exercise of common stock warrants, shares				1,648,709
Net loss	(7,972)					(7,972)
Ending balance at Mar. 31, 2021	171,252			$ 3	291,633	(120,384)
Ending balance, shares at Mar. 31, 2021				30,588,495
Beginning balance at Dec. 31, 2021	146,513			$ 3	296,049	(149,206)	$ (333)
Beginning balance, shares at Dec. 31, 2021				30,609,029
Stock-based compensation expense	1,515				1,515
Exercise of options into common stock	$ 237				237
Exercise of options into common stock, shares	73,784			73,784
Employee stock purchase plan expense	$ 14				14
Unrealized loss on marketable securities	(566)						(566)
Net loss	(12,405)					(12,405)
Ending balance at Mar. 31, 2022	$ 135,308			$ 3	$ 297,815	$ (161,611)	$ (899)
Ending balance, shares at Mar. 31, 2022				30,682,813

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Operating activities
Net loss	$ (12,405)	$ (7,972)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	1,515	1,349
Depreciation and amortization	157	98
Accretion on marketable securities	197
Interest on finance lease	46	3
Non-cash lease expense	291
Amortization of financing lease right-of-use assets	177
Realized gain on marketable securities	(15)
Changes in operating assets and liabilities:
Prepaid expenses	(2,007)	(1,992)
Other assets	175	50
Accounts payable and accrued liabilities	2,644	(1,880)
Compensation and employee benefits	(1,193)	(475)
Operating lease liabilities	(271)
Other liabilities	(15)	52
Net cash used in operating activities	(10,750)	(10,767)
Investing activities
Purchases of property and equipment	(19)	(487)
Purchases of short-term investments	(8,017)
Sales of short-term investments	12,365
Maturities of short-term investments	7,864
Net cash provided by (used in) investing activities	12,193	(487)
Financing activities
Principle payments from financing leases	(133)	(10)
Proceeds from the exercise of common stock options	238	1
Employee stock purchase plan expense	14
Proceeds from issuance of common stock upon initial public offering, net of issuance costs		140,594
Net cash provided by financing activities	119	164,076
Net increase in cash and cash equivalents	1,562	152,822
Cash and cash equivalents at beginning of period	7,159	16,596
Cash and cash equivalents at end of period	8,721	169,418
Supplemental disclosure of noncash financing information:
Property and equipment additions included in accounts payable and accrued liabilities	11	15
Deferred offering costs included in accounts payable and accrued liabilities		534
Interest on financing		3
Initial measurement of operating lease right-of-use assets	6,558
Initial measurement of operating lease liabilities	5,580
Initial measurement of finance lease right-of-use assets	$ 411
Series BB Convertible Preferred Stock
Financing activities
Proceeds on the issuance of convertible preferred stock		23,491
Conversion of Series AA and BB Convertible Preferred Stock into Common Stock
Supplemental disclosure of noncash financing information:
Conversion of stock		$ 95,826

Organization and Operations

Organization and Operations	3 Months Ended
	Mar. 31, 2022
Organization Consolidation And Presentation Of Financial Statements [Abstract]
ORGANIZATION AND OPERATIONS	1. ORGANIZATION AND OPERATIONS Business Sensei Biotherapeutics, Inc. (the “Company” or “Sensei”) is a biopharmaceutical company that was incorporated in 1999 as a Maryland corporation until incorporated in Delaware on December 1, 2017. The Company is engaged in the discovery, development and delivery of next generation immunotherapies with an initial focus on treatments for cancer. Liquidity and capital resources Since its inception, the Company has devoted substantially all of its resources to advancing development of its portfolio of programs, establishing and protecting its intellectual property, conducting research and development activities, organizing and staffing the Company, business planning, raising capital and providing general and administrative support for these operations. The Company is subject to risks and uncertainties common to early-stage companies in the biotechnology industry including, but not limited to, technical risks associated with the successful research, development and manufacturing of product candidates, development by competitors of new technological innovations, dependence on key personnel, protection of proprietary technology, compliance with government regulations and the ability to secure additional capital to fund operations. Current and future programs will require significant research and development efforts, including extensive preclinical and clinical testing and regulatory approval prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel and infrastructure. Even if the Company’s drug development efforts are successful, it is uncertain when, if ever, the Company will realize significant revenue from product sales. Since its inception, the Company has incurred substantial losses and had a net loss of $ 12.4 million for the three months ended March 31, 2022. As of March 31, 2022, the Company had an accumulated deficit of $ 161.6 million . The Company expects to generate operating losses and negative operating cash flows for the foreseeable future. In February 2021, the Company completed its initial public offering (“IPO”), in which the Company issued and sold 8,030,295 shares of its common stock at a public offering price of $ 19.00 per share, for aggregate gross proceeds of $ 152.6 million. The Company received $ 138.5 million in net proceeds after deducting underwriting discounts and estimated offering expenses payable by the Company. The Company expects that its cash, cash equivalents and marketable securities as of March 31, 2022 of $ 136.2 million will be sufficient to fund its operations for at least the next twelve months from the date of issuance of these financial statements. The Company will need additional financing to support its continuing operations and pursue its growth strategy. Until such time as the Company can generate significant revenue from product sales, if ever, it expects to finance its operations through a combination of equity offerings, debt financings, collaborations, strategic alliances and licensing arrangements. The Company may be unable to raise additional funds or enter into such other agreements when needed on favorable terms or at all. The inability to raise capital as and when needed would have a negative impact on the Company’s financial condition and its ability to pursue its business strategy. The Company will need to generate significant revenue to achieve profitability, and it may never do so. Reverse stock split On January 29, 2021, the Company effected a reverse stock split of the Company’s common stock on a 48-for-1 basis (the “Reverse Stock Split”). In connection with the Reverse Stock Split, the conversion ratio for the Company’s Series AA and Series BB convertible preferred stock was proportionately adjusted such that the common stock issuable upon conversion of such preferred stock was decreased in proportion to the Reverse Stock Split. Accordingly, all common stock share and per share amounts, as well as all preferred stock conversion ratios, for all periods presented in these financial statements have been retroactively adjusted, to reflect this reverse stock split and adjustment of the Series AA and BB convertible preferred stock conversion ratios.

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2022
Accounting Policies [Abstract]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Basis of Presentation and Principles of Consolidation The Company has prepared the accompanying condensed consolidated financial statements in conformity with generally accepted accounting principles in the United States (“US GAAP”). The condensed consolidated financial statements include those accounts of the Company and its subsidiaries after elimination of all intercompany accounts and transactions. Unaudited interim financial information The condensed consolidated financial statements of the Company included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). Certain information and note disclosures normally included in financial statements prepared in accordance with US GAAP have been condensed or omitted from these condensed consolidated financial statements, as is permitted by such rules and regulations. Accordingly, these condensed consolidated financial statements should be read in conjunction with the financial statements and notes thereto included in the Company’s Annual Report on Form 10-K. The results for any interim period are not necessarily indicative of results for any future period. Use of Estimates The preparation of condensed consolidated financial statements in conformity with US GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements, and the reported amounts of expenses during the reporting periods presented. Estimates are used for, but are not limited to, depreciation of equipment, the Company’s enterprise value, fair value of financial instruments, the Company’s ability to continue as a going concern and contingencies. Actual results may differ from those estimates. Cash and cash equivalents Cash equivalents are highly liquid investments with an original maturity of 90 days or less at the date of purchase and consist of time deposits and investments in money market funds with commercial banks and financial institutions. At March 31, 2022 , cash and cash equivalents included cash on deposit at commercial banks and a money market fund that invests in U.S. Government securities. Marketable securities Investments consist of marketable securities with original maturities greater than 90 days. The Company has classified its investments with maturities beyond one year as short-term, based on their highly liquid nature and because such marketable securities represent the investment of cash that is available for current operations. The Company considers its investment portfolio of marketable securities to be available-for-sale. Accordingly, these investments are recorded at fair value (level 2). Unrealized gains and losses are reported as the accumulated other comprehensive items in stockholders’ equity. Amortization and accretion of premiums and discounts are recorded in other income (expense). Realized gains or losses on debt securities are included in interest income or interest expense, respectively. If any adjustment to fair value reflects a decline in value of the investment, the Company considers all available evidence to evaluate the extent to which the decline is other than temporary and, if so, marks the investment to market on the Company’s statement of operations and comprehensive loss. Leases Prior to January 1, 2022, the Company accounted for leases in accordance with ASC 840, Leases ("ASC 840"). At lease inception, the Company determined if an arrangement was an operating or capital lease. For operating leases, the Company recognized rent expense, inclusive of rent escalations, holidays and lease incentives, on a straight-line basis over the lease term. The difference between rent expense recorded and the amount paid was charged to deferred rent. The Company presented lease incentives as deferred rent and amortized the incentives as a reduction to rent expense on a straight-line basis over the lease term. The Company classified deferred rent as current and noncurrent liabilities based on the portion of the deferred rent that was scheduled to mature within the proceeding twelve months. Effective January 1, 2022, the Company accounts for leases in accordance with Accounting Standards Update ("ASU") No. 2016-02, Leases (Topic 842) (“ASC 842”). At contract inception, the Company determines if an arrangement is or contains a lease. A lease conveys the right to control the use of an identified asset for a period of time in exchange for consideration. If determined to be or contain a lease, the lease is assessed for classification as either an operating or finance lease at the lease commencement date, defined as the date on which the leased asset is made available for use by the Company, based on the economic characteristics of the lease. For each lease with a term greater than twelve months, the Company records a right-of-use asset and lease liability. A right-of-use asset represents the economic benefit conveyed to the Company by the right to use the underlying asset over the lease term. A lease liability represents the obligation to make lease payments arising from the lease. The Company elected the practical expedient to not separate lease and non-lease components for all classes of underlying assets and therefore measures each lease payment as the total of the fixed lease and associated non-lease components. Lease liabilities are measured at lease commencement and calculated as the present value of the future lease payments in the contract using the rate implicit in the contract, when available. If an implicit rate is not readily determinable, the Company uses an incremental borrowing rate measured as the rate at which the Company could borrow, on a fully collateralized basis, a commensurate loan in the same currency over a period consistent with the lease term at the commencement date. Right-of-use assets are measured as the lease liability plus initial direct costs and prepaid lease payments, less lease incentives granted by the lessor. The lease term is measured as the noncancelable period in the contract, adjusted for any options to extend or terminate when it is reasonably certain the Company will extend the lease term via such options based on an assessment of economic factors present as of the lease commencement date. The Company elected the practical expedient to not recognize leases with a lease term of twelve months or less. Components of a lease are split into three categories: lease components, non-lease components, and non-components. The fixed and in-substance fixed contract consideration (including any consideration related to non-components) are allocated, based on the respective relative fair values, to the lease components and non-lease components. The Company has elected to account for lease and non-lease components together as a single lease component for all underlying assets and allocate all of the contract consideration to the lease component only. The Company’s operating and finance leases are presented in the consolidated balance sheet as lease right-of-use assets, classified as noncurrent assets, and lease liabilities, classified as current and noncurrent liabilities. Operating and finance lease expense is recognized on a straight-line basis over the lease term. Variable costs associated with a lease, such as maintenance and utilities, are not included in the measurement of the lease liabilities and right-of-use assets but rather are expensed when the events determining the amount of variable consideration to be paid have occurred. ASC 842 provides several optional practical expedients in transition. The Company applied the ‘package of practical expedients’ which allow the Company to not reassess whether existing or expired arrangements contain a lease, the lease classification of existing or expired leases, or whether previous initial direct costs would qualify for capitalization under ASC 842. The adoption of ASC 842 resulted in the recognition of operating lease liabilities of $ 6.7 million and operating right-of-use assets of $ 6.6 million, along with the write-off of certain deferred rent balances of $ 0.1 million within the Company’s condensed consolidated balance sheets as of January 1, 2022. Leases previously reported as capital leases are now referred to as finance leases. The adoption did not have a significant impact on the Company’s condensed consolidated statements of operations and comprehensive loss and condensed consolidated statements of cash flows. Recently Issued Accounting Standards Updates In June 2016, the FASB issued ASU No. 2016-13, “Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments,” which was subsequently amended in November 2018 through ASU No. 2018-19, “Codification Improvements to Topic 326, Financial Instruments—Credit Losses.” ASU No. 2016-13 will require entities to estimate lifetime expected credit losses for trade and other receivables, net investments in leases, financing receivables, debt securities and other instruments, which will result in earlier recognition of credit losses. Further, the new credit loss model will affect how entities in all industries estimate their allowance for losses for receivables that are current with respect to their payment terms. ASU No. 2018-19 further clarifies that receivables arising from operating leases are not within the scope of Topic 326. Instead, impairment from receivables of operating leases should be accounted for in accordance with Topic 842, Leases. As per the latest ASU 2020-02, FASB deferred the timelines for certain small public and private entities, thus the new guidance will be adopted by the Company for the annual reporting period beginning January 1, 2023, including interim periods within that annual reporting period. The standard will apply as a cumulative-effect adjustment to retained earnings as of the beginning of the first reporting period in which the guidance is adopted. The Company does not expect adoption of this new guidance to have a material impact on its results of operations, financial condition, and financial statement disclosures.

Marketable Securities

Marketable Securities	3 Months Ended
	Mar. 31, 2022
Investments Debt And Equity Securities [Abstract]
MARKETABLE SECURITIES	3. MARKETABLE SECURITIES Marketable securities consist of the following as of March 31, 2022 (in thousands): Amortized Cost Unrealized Gains Unrealized Losses Fair Value Commercial paper $ 39,494 $ - $ ( 30 ) $ 39,464 Corporate bonds 81,908 $ 3 $ ( 602 ) $ 81,309 U.S. Government agencies 7,000 $ - $ ( 270 ) $ 6,730 Total $ 128,402 $ 3 $ ( 902 ) $ 127,503 As of March 31, 2022 , all marketable securities held by the Company had remaining contractual maturities of one year or less, except for corporate bonds and U.S. government agencies securities with a fair value of $ 62.5 million that had maturities of one to three years . As of March 31, 2022, $ 118 thousand and $ 781 thousand of unrealized losses were associated with marketable securities with contractual maturities of one year or less and more than one year , respectively. There were no impairments of the Company’s assets measured and carried at fair value during the three months ended March 31, 2022 .

Property and Equipment, Net

Property and Equipment, Net	3 Months Ended
	Mar. 31, 2022
Property Plant And Equipment [Abstract]
PROPERTY AND EQUIPMENT, NET	4. PROPERTY AND EQUIPMENT, NET Property and equipment, net consist of the following (in thousands): March 31, December 31, Research equipment $ 2,761 $ 4,974 Office equipment and furniture 536 606 Leaseholder improvement 253 253 Total property and equipment 3,550 5,833 Less accumulated depreciation and amortization ( 1,346 ) ( 1,189 ) Property and equipment, net $ 2,204 $ 4,644 Depreciation and amortization expense for the three months ended March 31, 2022 and 2021 was $ 157 thousand and $ 98 thousand , respectively. Effective January 1, 2022, the Company adopted ASC 842 and reclassed capital leases that were previously classified as property and equipment, net were presented separately under right of use assets - financing leases, net on the Company's condensed consolidated balance sheet. $ 2.2 million relates to items previously classified under research equipment and $ 70 thousand relates to items previously classified under office equipment and furniture on the table above. These leases are further described in Note 7.

Debt

Debt	3 Months Ended
	Mar. 31, 2022
Debt Disclosure [Abstract]
DEBT	. Debt In May 2020, the Company received $ 567 thousand in loan funding from the Paycheck Protection Program (“PPP”) pursuant to the Coronavirus Aid, Relief, and Economic Security Act, as amended by the Flexibility Act, and administered by the Small Business Administration. The unsecured loan (the “PPP Loan”) is with Silicon Valley Bank. Under the terms of the PPP Loan, interest accrued on the outstanding principal at a rate of 1.0 % per annum. On August 6, 2021, the Small Business Administration approved the forgiveness for the full amount of the PPP Loan, which included principal of $ 567 thousand, plus interest. The Company recognized a gain on debt extinguishment in other income (expense) on the Consolidated Statement of Operations and Comprehensive Loss for the year ended December 31, 2021.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2022
Fair Value Disclosures [Abstract]
FAIR VALUE MEASUREMENTS	. FAIR VALUE MEASUREMENTS The following tables present information about the Company’s financial assets and liabilities measured at fair value on a recurring basis and indicate the level of the fair value hierarchy used to determine such fair values (in thousands): Fair value measurements at March 31, 2022 Level 1 Level 2 Level 3 Total Assets: Cash equivalents Money market funds $ 5,248 $ - $ - $ 5,248 Investments: Commercial paper - 39,464 - 39,464 Corporate bonds - 81,309 - 81,309 U.S. Government agencies - 6,730 - 6,730 Total $ 5,248 $ 127,503 $ - $ 132,751 When developing fair value estimates, the Company maximizes the use of observable inputs and minimizes the use of unobservable inputs. When available, the Company uses quoted market prices to measure fair value. The valuation technique used to measure fair value for the Company's Level 1 and Level 2 assets is a market approach, using prices and other relevant information generated by market transactions involving identical or comparable assets. If market prices are not available, the fair value measurement is based on models that use primarily market-based parameters including yield curves, volatilities, credit ratings and currency rates. In certain cases where market rate assumptions are not available, the Company is required to make judgments about assumptions market participants would use to estimate the fair value of a financial instrument. There were no transfers among Level 1, Level 2 or Level 3 categories in the three months ended March 31, 2022 or 2021.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2022
Commitments And Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	7. COMMITMENTS AND CONTINGENCIES Operating Leases As of March 31, 2022, the Company leases office and laboratory facilities under operating leases, which expire at various dates through 2027 . As part of its adoption of ASC 842, the Company recorded operating right-of-use assets and operating lease liabilities for these leases as of January 1, 2022. On May 14, 2021, the Company commenced a lease for approximately 10,082 square feet at 451 D Street in Boston, MA. This serves as the Company’s principal executive and administrative offices as well as laboratory space. The Company will pay a base monthly rent in the amount of $ 69 thousand during the first 12 months of the lease. Base monthly rent will increase annually, over the base monthly rent then in effect, by 3 %. On October 1, 2021, the Company commenced a lease for additional space of approximately 4,258 square feet at 451 D Street in Boston, MA. The Company will pay a base monthly rent in the amount of $ 33 thousand during the first 12 months of the lease. Base monthly rent will increase annually, over the base monthly rent then in effect, by 3 %. The lease terms for both leases at 451 D Street in Boston expire on September 30, 2026 , with a one-time option to renew for a period of five years . The renewal periods are not included in the measurement of these leases as the Company is not reasonably certain of exercising them. Both leases are secured with a letter of credit for $ 628 thousand. On November 1, 2020, the Company commenced a lease for approximately 7,643 square feet of space at 1405 Research Blvd in Rockville, MD. This serves primarily as laboratory space. The Company paid a base monthly amount of $ 25 thousand during the first 12 months. Base monthly rent will increase annually, over the base monthly rent then in effect, by 3 %. The lease is secured with a letter of credit for $ 50 thousand and the term expires on February 28, 2027 . Finance Leases The Company leases research equipment and furniture under finance leases. As part of its adoption of ASC 842, the Company recorded financing right-of-use assets and financing lease liabilities for these leases as of January 1, 2022. On April 20, 2021, the Company entered into a finance lease agreement with a third-party company related to various research equipment and furniture, which included the Company selling specific equipment for $ 293 thousand, resulting in a gain on the sale of $ 20 thousand, and leasing it back for a four-year period. The associated lease facility includes up to $ 5 million for the purchase of equipment on an as needed basis. As of March 31, 2022, the Company had $ 2.7 million available for purchases under this arrangement. The Company has an option to purchase the equipment at fair market value, not to exceed 15 % of the original equipment cost, or to renew the lease for an additional one - or two-year period at a mutually agreed upon rate. On September 27, 2021, the Company commenced a lease for various research equipment. The terms of the four-year lease specify a monthly payment of $ 13 thousand, with the option to purchase the equipment for fair market value, to be determined by the lessor, at the end of the lease. The following table contains a summary of the lease costs recognized under ASC 842 pertaining to the Company’s finance and operating leases for the three months ended March 31, 2022 (in thousands): Three Months Ended March 31, 2022 Lease Cost: Amortization of finance right-of-use assets $ 177 Interest on finance lease liabilities 46 Operating lease cost 414 Variable lease cost 173 Total lease costs $ 810 The following table contains a summary of other information pertaining to the Company’s finance and operating leases for the three months ended March 31, 2022 (in thousands, except lease term and discount rate): Three Months Ended March 31, 2022 Other Operating Lease Information: Operating cash flows for operating leases $ 392 Operating cash flows for finance leases $ 46 Financing cash flows from finance leases $ 133 Weighted average remaining lease term Operating leases 4.6 years Financing leases 3.7 years Weighted average discount rate Operating leases 7.6 % Financing leases 8.3 % The following table presents supplemental balance sheet information related to operating and financing leases as of March 31, 2022 (in thousands): March 31, Operating leases Right-of-use assets $ 6,267 Right-of-use lease liabilities, current $ 1,160 Right-of-use lease liabilities, noncurrent 5,278 Total operating lease liabilities $ 6,438 Financing leases Right-of-use assets, net $ 2,551 Right-of-use lease liabilities, current $ 786 Right-of-use lease liabilities, noncurrent 1,846 Total financing lease liabilities $ 2,632 The following table presents the maturity of the Company’s operating and finance lease liabilities as of March 31, 2022 (in thousands): Operating Financing Remainder of 2022 $ 1,196 $ 609 2023 1,628 812 2024 1,640 714 2025 1,689 683 2026 1,413 80 Thereafter 59 — Total future minimum lease payments $ 7,625 $ 2,898 Less amount representing interest 1,187 266 Total lease liabilities $ 6,438 $ 2,632 The following table presents operating lease commitments as reflected under ASC 840 as of December 31, 2021 (in thousands): Operating 2022 1,585 2023 1,606 2024 1,641 2025 1,689 2026 1,413 2027 59 Total operating lease obligations $ 7,993 The following table presents finance lease commitments as reflected under ASC 840 as of December 31, 2021 (in thousands): Financing 2022 $ 699 2023 674 2024 674 2025 553 2026 47 Total capital lease obligations 2,647 Less amount representing interest ( 293 ) Present value of minimum capital lease obligations $ 2,354 License Agreements In the normal course of business, the Company enters into licensing agreements with various parties to obtain the right to make, use, and sell licensed products currently in development. Litigation The Company records estimated losses from loss contingencies, such as a loss arising from a litigation, when it determines that it is probable a liability has been incurred and the amount of loss can be reasonably estimated. Litigation is subject to many factors that are difficult to predict so that there can be no assurance, in the event of a material unfavorable result in one or more claims, the Company will not incur material costs. During 2017, the Company became actively involved in a matter pending in the Ontario (Canada) Superior Court of Justice which names, among multiple other defendants, the Company and two former officers of the Company. The claims pending in this matter allege breach of contract by the Company and seek declaratory and other relief, including monetary damages from the Company, and the individual defendants, including the Company’s former officers. The claims by such plaintiffs were originally made in a lawsuit filed in Ontario during October 2011, but was not pursued by such plaintiffs in any material manner until 2017. The Company believes that there is no merit to the claims alleged against the Company and its former officers, including no alleged breach of contract by the Company, and intends to vigorously defend against the claims pertaining to the Company and its former officers. At the present stage of the suit, management believes the outcome in this matter is not likely to have any material impact on the Company’s results, cash flows, or financial position. Coronavirus pandemic On January 30, 2020, the World Health Organization ("WHO") announced a global health emergency because of a new strain of coronavirus originating in Wuhan, China and the risks to the international community as the virus spreads globally beyond its point of origin. In March 2020, the WHO classified the COVID-19 outbreak as a pandemic, based on the rapid increase in exposure globally. The full impact of the COVID-19 pandemic continues to evolve as of the date of these financial statements. As such, it is uncertain as to the full magnitude that the pandemic will have on the Company’s financial condition, liquidity, and future results of operations. Management is actively monitoring the global situation on its financial condition, liquidity, operations, suppliers, industry, and workforce. Given the daily evolution of the COVID-19 pandemic and the global responses to curb its spread, the Company is not able to estimate the effects of the COVID-19 pandemic on its results of operations, financial condition, or liquidity. Although the Company cannot estimate the length or gravity of the impact of the COVID-19 pandemic at this time, if the pandemic continues, it may have a material adverse effect on the Company’s results of future operations, financial position, and liquidity during the remainder of 2022 and beyond.

Equity

Equity	3 Months Ended
	Mar. 31, 2022
Equity [Abstract]
EQUITY	. Equity Each share of common stock entitles the holder to one vote on all matters submitted to a vote of the Company’s stockholders. Common stockholders are not entitled to receive dividends, unless declared by the board of directors. Series BB Convertible Preferred Stock Issuance In January 2021, the Company issued and sold 113,275,902 shares of Series BB convertible preferred stock at $ 0.207383 per share in exchange for $ 23.5 million in gross proceeds. Initial Public Offering In February 2021, the Company completed its IPO in which the Company issued and sold 8,030,295 shares of its common stock, including 1,030,243 shares pursuant to the partial exercise of the underwriters’ option to purchase additional shares, at a public offering price of $ 19.00 per share, for aggregate gross proceeds of $ 152.6 million. The Company received approximately $ 138.5 million in net proceeds after deducting underwriting discounts and estimated offering expenses payable by the Company. Upon closing of the IPO on February 8, 2021, all of the Company’s outstanding preferred stock converted into an aggregate of 19,034,069 shares of common stock. On February 8, 2021, in connection with the IPO, the Company filed an Amended and Restated Certificate of Incorporation (the “Amended Certificate”) with the Secretary of State of the State of Delaware. The Amended Certificate, among other things: (i) authorized 250,000,000 shares of common stock; (ii) eliminated all references to the previously existing series of preferred stock; and (iii) authorized 10,000,000 shares of undesignated preferred stock that may be issued from time to time by the Company’s board of directors in one or more series. Common Stock Warrants The following is a summary of the common stock warrant activity related to common stock warrants issued in conjunction with equity and debt fundraising events for the three months ended March 31, 2022: Number Weighted- Weighted- Aggregate Outstanding at December 31, 2021 412,262 $ 9.81 5.71 $ 723 Granted — $ — Exercised — $ — Expired — Outstanding at March 31, 2022 412,262 $ 9.81 5.47 $ —

Stock-Based Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2022
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
STOCK-BASED COMPENSATION	9. STOCK-BASED COMPENSATION 2018 Equity Incentive Plan The Company’s 2018 Stock Incentive Plan (the “2018 Plan”), provided for the Company to grant qualified incentive options, nonqualified options, stock grants and other stock-based awards to employees and non-employees to purchase the Company’s common stock. Upon the effectiveness of the 2021 Plan (as defined below), no further issuances will be made under the 2018 Plan. 2021 Stock Option and Incentive Plan The 2021 Equity Incentive Plan (the “2021 Plan”) was approved by the board of directors on January 27, 2021, and the Company’s stockholders on January 28, 2021 and became effective on the execution of the underwriting agreement related to the initial public offering. The 2021 Plan, which superseded the Company’s previous equity incentive plan, provides for the grant of incentive stock options to employees, including employees of any parent or subsidiary corporations, and for the grant of nonstatutory stock options, stock appreciation rights, restricted stock awards, restricted stock unit awards, performance awards and other forms of stock awards to employees, directors, and consultants, including employees and consultants of the Company’s affiliates. The number of shares initially reserved for issuance under the 2021 Plan was 5,000,000 , which began automatically increasing on January 1 of each calendar year, starting on January 1, 2022 through January 1, 2031, in an amount equal to 4.0 % of the total number of shares of the Company’s capital stock outstanding on the last day of the calendar month before the date of each automatic increase, or a lesser number of shares determined by the board of directors. There were 2,504,400 shares reserved for issuance pursuant to the 2021 Plan as of March 31, 2022. 2021 Employee Stock Purchase Plan The 2021 Employee Stock Purchase Plan (the “2021 ESPP”) was approved by the Company’s board of directors on January 27, 2021 and became effective on the execution of the underwriting agreement related to the initial public offering. A total of 333,333 shares of common stock were initially reserved for this issuance under the 2021 ESPP, which will automatically increase on January 1 of each calendar year, beginning on January 1, 2022 through January 1, 2031, by an amount equal to 1.0 % of the total shares of common stock outstanding on December 31st of the preceding calendar year. The purchase price of the shares under the 2021 ESPP are at 85 % of the lower of the fair market value of the Company’s common stock on the first trading day of the offering period or on the purchase date. As of March 31, 2022 , the Company had issued 11,700 shares under the 2021 ESPP. As of March 31, 2022 , 627,723 shares were available to be issued under the 2021 ESPP. The Company recognized no share-based compensation expense related to the ESPP for the three months ended March 31, 2022. Stock Options During 2022, the Company granted options to purchase shares of common stock to employees, consultants, and nonexecutive directors pursuant to the 2021 Plan. The Company uses the Black-Scholes option-pricing model to estimate the fair value of the stock options on the grant dates at a weighted average fair value of $ 3.13 per share. The following is a summary of the stock option award activity during the three months ended March 31, 2022: Number Weighted- Weighted- Aggregate Outstanding at December 31, 2021 3,026,464 $ 10.84 8.51 $ 6,403 Granted 681,704 $ 4.05 Exercised ( 73,784 ) $ 3.22 Forfeited ( 206,800 ) $ 9.58 Expired — $ — Outstanding at March 31, 2022 3,427,584 $ 9.73 8.58 $ — Options expected to vest as of March 31, 2022 2,262,393 $ 8.03 9.12 $ — Exercisable at March 31, 2022 1,165,191 $ 13.03 7.53 $ — The aggregate intrinsic value of stock options exercised in the three months ended March 31, 2022 was $ 0.1 million. The total fair value of options vested during the three months ended March 31, 2022 was $ 4.1 million. At March 31, 2022 , there was approximately $ 15.2 million of unrecognized stock-based compensation expense associated with the stock options, which is expected to be recognized over a weighted-average period of 2.87 years. Restricted Stock Units The Company has granted restricted stock units with service vesting based conditions. The following is a summary of the restricted stock unit activity during the three months ended March 31, 2022: Restricted Stock Units Weighted- Unvested at December 31, 2021 — — Granted 205,201 $ 4.02 Unvested at March 31, 2022 205,201 $ 4.02 Pursuant to the 2021 Plan, the Company granted restricted stock units which vest annually over a period of one , two or four years . No restricted stock units vested during the three months ended March 31, 2022. At March 31, 2022 , there was approximately $ 0.8 million of unrecognized stock-based compensation expense associated with the restricted stock units which is expected to be recognized over a weighted-average period of 3.63 years. Common Stock Warrants The following is a summary of the employee-issued common stock warrant activity during the three months ended March 31, 2022: Number Weighted- Weighted- Aggregate Outstanding at December 31, 2021 57,004 $ 6.94 2.91 $ 2 Granted — $ — Exercised — $ — Expired — $ — Outstanding and exercisable at March 31, 2022 57,004 $ 6.94 2.66 $ — As of March 31, 2022 there was no unrecognized stock-based compensation expense associated with the common stock warrants. For the three months ended March 31, 2022 , the Company utilized the Black-Scholes option-pricing model for estimating the fair value of the stock options granted. The following table presents the assumptions and the Company’s methodology for developing each of the assumptions used: Three Months Ended March 31, 2022 2021 Volatility 93.67 %- 95.8 % 91.5 %- 98.04 % Expected life (years) 5.8 4- 7 5.52 - 6.08 Risk-free interest rate 1.7 %– 2.4 % 0.5 %- 0.1 .0% Dividend rate —% —% • Volatility—The Company estimates the expected volatility of its common stock at the date of grant based on the historical volatility of comparable public companies over the expected term. • Expected life—The expected life is estimated as the contractual term. • Risk-free interest rate—The risk-free rate for periods within the estimated life of the stock award is based on the U.S. Treasury yield curve in effect at the time of grant. • Dividend rate—The assumed dividend yield is based upon the Company’s expectation of not paying dividends in the foreseeable future. Stock-based compensation expense was recorded in the following line items in the condensed consolidated statements of operations for the three months ended March 31, 2022 and 2021 (in thousands): Three Months Ended March 31, 2022 2021 Research and development $ 555 $ 509 General and administrative 960 840 Total stock-based compensation expense $ 1,515 $ 1,349

Employee Retirement Plan

Employee Retirement Plan	3 Months Ended
	Mar. 31, 2022
Compensation And Retirement Disclosure [Abstract]
EMPLOYEE RETIREMENT PLAN	10. EMPLOYEE RETIREMENT PLAN The Company maintains a defined contribution 401(k) profit-sharing plan (the “Plan”) for all employees. Under the Plan, participants may make voluntary contributions up to the maximum amount allowable by law. The Plan is based on employees’ salary deferral, and the Company matches employees’ contributions up to 4 % of the employees’ base salary. Employees are 100 % vested in the Company’s match contributions. During the three months ended March 31, 2022 and 2021, the Company's matching contributions were $ 106 thousand and $ 29 thousand, respectively.

Related-Party Transactions

Related-Party Transactions	3 Months Ended
	Mar. 31, 2022
Related Party Transactions [Abstract]
RELATED-PARTY TRANSACTIONS	11. RELATED-PARTY TRANSACTIONS Service Agreement During 2020, the Company entered into a service agreement with Hope Farms at Disco Bay LLC ("Hope Farms") to provide animal vaccination testing and provide samples to the Company. The Company’s Chief Research and Development Officer is a co-founder and partial owner of Hope Farms. Further, the CEO of Hope Farms is the spouse of the Company’s Chief Research and Development Officer. Expenses booked by the Company relating to this service agreement for the three months ended March 31, 2022 and 2021 were $ 28 thousand and $ 52 thousand, respectively. In the first quarter of 2022, the Company also made a payment of $ 47 thousand to Hope Farms that was outstanding at the end of 2021.

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2022
Income Tax Disclosure [Abstract]
INCOME TAXES	12. INCOME TAXES The Company recorded no provision for income taxes for the three months ended March 31, 2022 and 2021. Deferred tax assets and deferred tax liabilities are recognized based on temporary differences between the financial reporting and tax bases of assets and liabilities using statutory rates. 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 has been established against the Company’s otherwise recognizable net deferred tax assets.

Net Loss Per Share

Net Loss Per Share	3 Months Ended
	Mar. 31, 2022
Earnings Per Share [Abstract]
NET LOSS PER SHARE	13. NET LOSS PER SHARE Basic and diluted net loss per share attributable to common stockholders is calculated as follows (in thousands except share and per share amounts): Three Months Ended March 31, 2022 2021 Net loss $ ( 12,405 ) $ ( 7,972 ) Net loss attributable to common stockholders $ ( 12,405 ) $ ( 7,972 ) Net loss per share—basic and diluted $ ( 0.40 ) $ ( 0.42 ) Weighted-average number of shares used in computing net loss per share—basic and diluted 30,647,679 18,904,853 The following outstanding potentially dilutive securities have been excluded from the calculation of diluted net loss per share, as their effect is anti-dilutive: For the Three Months Ended March 31, 2022 2021 Stock options to purchase common stock 3,427,584 3,157,199 Unvested restricted stock units 205,201 — Warrants issued to employees and contractor to purchase common stock 57,212 57,212 Warrants issued related to convertible notes and other equity agreements 412,262 412,262

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2022
Accounting Policies [Abstract]
Basis of Presentation and Principles of Consolidation	Basis of Presentation and Principles of Consolidation The Company has prepared the accompanying condensed consolidated financial statements in conformity with generally accepted accounting principles in the United States (“US GAAP”). The condensed consolidated financial statements include those accounts of the Company and its subsidiaries after elimination of all intercompany accounts and transactions.
Unaudited interim financial information	Unaudited interim financial information The condensed consolidated financial statements of the Company included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). Certain information and note disclosures normally included in financial statements prepared in accordance with US GAAP have been condensed or omitted from these condensed consolidated financial statements, as is permitted by such rules and regulations. Accordingly, these condensed consolidated financial statements should be read in conjunction with the financial statements and notes thereto included in the Company’s Annual Report on Form 10-K. The results for any interim period are not necessarily indicative of results for any future period.
Use of Estimates	Use of Estimates The preparation of condensed consolidated financial statements in conformity with US GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements, and the reported amounts of expenses during the reporting periods presented. Estimates are used for, but are not limited to, depreciation of equipment, the Company’s enterprise value, fair value of financial instruments, the Company’s ability to continue as a going concern and contingencies. Actual results may differ from those estimates.
Cash and Cash Equivalents	Cash and cash equivalents Cash equivalents are highly liquid investments with an original maturity of 90 days or less at the date of purchase and consist of time deposits and investments in money market funds with commercial banks and financial institutions. At March 31, 2022 , cash and cash equivalents included cash on deposit at commercial banks and a money market fund that invests in U.S. Government securities.
Marketable Securities	Marketable securities Investments consist of marketable securities with original maturities greater than 90 days. The Company has classified its investments with maturities beyond one year as short-term, based on their highly liquid nature and because such marketable securities represent the investment of cash that is available for current operations. The Company considers its investment portfolio of marketable securities to be available-for-sale. Accordingly, these investments are recorded at fair value (level 2). Unrealized gains and losses are reported as the accumulated other comprehensive items in stockholders’ equity. Amortization and accretion of premiums and discounts are recorded in other income (expense). Realized gains or losses on debt securities are included in interest income or interest expense, respectively. If any adjustment to fair value reflects a decline in value of the investment, the Company considers all available evidence to evaluate the extent to which the decline is other than temporary and, if so, marks the investment to market on the Company’s statement of operations and comprehensive loss.
Leases	Leases Prior to January 1, 2022, the Company accounted for leases in accordance with ASC 840, Leases ("ASC 840"). At lease inception, the Company determined if an arrangement was an operating or capital lease. For operating leases, the Company recognized rent expense, inclusive of rent escalations, holidays and lease incentives, on a straight-line basis over the lease term. The difference between rent expense recorded and the amount paid was charged to deferred rent. The Company presented lease incentives as deferred rent and amortized the incentives as a reduction to rent expense on a straight-line basis over the lease term. The Company classified deferred rent as current and noncurrent liabilities based on the portion of the deferred rent that was scheduled to mature within the proceeding twelve months. Effective January 1, 2022, the Company accounts for leases in accordance with Accounting Standards Update ("ASU") No. 2016-02, Leases (Topic 842) (“ASC 842”). At contract inception, the Company determines if an arrangement is or contains a lease. A lease conveys the right to control the use of an identified asset for a period of time in exchange for consideration. If determined to be or contain a lease, the lease is assessed for classification as either an operating or finance lease at the lease commencement date, defined as the date on which the leased asset is made available for use by the Company, based on the economic characteristics of the lease. For each lease with a term greater than twelve months, the Company records a right-of-use asset and lease liability. A right-of-use asset represents the economic benefit conveyed to the Company by the right to use the underlying asset over the lease term. A lease liability represents the obligation to make lease payments arising from the lease. The Company elected the practical expedient to not separate lease and non-lease components for all classes of underlying assets and therefore measures each lease payment as the total of the fixed lease and associated non-lease components. Lease liabilities are measured at lease commencement and calculated as the present value of the future lease payments in the contract using the rate implicit in the contract, when available. If an implicit rate is not readily determinable, the Company uses an incremental borrowing rate measured as the rate at which the Company could borrow, on a fully collateralized basis, a commensurate loan in the same currency over a period consistent with the lease term at the commencement date. Right-of-use assets are measured as the lease liability plus initial direct costs and prepaid lease payments, less lease incentives granted by the lessor. The lease term is measured as the noncancelable period in the contract, adjusted for any options to extend or terminate when it is reasonably certain the Company will extend the lease term via such options based on an assessment of economic factors present as of the lease commencement date. The Company elected the practical expedient to not recognize leases with a lease term of twelve months or less. Components of a lease are split into three categories: lease components, non-lease components, and non-components. The fixed and in-substance fixed contract consideration (including any consideration related to non-components) are allocated, based on the respective relative fair values, to the lease components and non-lease components. The Company has elected to account for lease and non-lease components together as a single lease component for all underlying assets and allocate all of the contract consideration to the lease component only. The Company’s operating and finance leases are presented in the consolidated balance sheet as lease right-of-use assets, classified as noncurrent assets, and lease liabilities, classified as current and noncurrent liabilities. Operating and finance lease expense is recognized on a straight-line basis over the lease term. Variable costs associated with a lease, such as maintenance and utilities, are not included in the measurement of the lease liabilities and right-of-use assets but rather are expensed when the events determining the amount of variable consideration to be paid have occurred. ASC 842 provides several optional practical expedients in transition. The Company applied the ‘package of practical expedients’ which allow the Company to not reassess whether existing or expired arrangements contain a lease, the lease classification of existing or expired leases, or whether previous initial direct costs would qualify for capitalization under ASC 842. The adoption of ASC 842 resulted in the recognition of operating lease liabilities of $ 6.7 million and operating right-of-use assets of $ 6.6 million, along with the write-off of certain deferred rent balances of $ 0.1 million within the Company’s condensed consolidated balance sheets as of January 1, 2022. Leases previously reported as capital leases are now referred to as finance leases. The adoption did not have a significant impact on the Company’s condensed consolidated statements of operations and comprehensive loss and condensed consolidated statements of cash flows.
Recently Issued Accounting Standards Updates	Recently Issued Accounting Standards Updates In June 2016, the FASB issued ASU No. 2016-13, “Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments,” which was subsequently amended in November 2018 through ASU No. 2018-19, “Codification Improvements to Topic 326, Financial Instruments—Credit Losses.” ASU No. 2016-13 will require entities to estimate lifetime expected credit losses for trade and other receivables, net investments in leases, financing receivables, debt securities and other instruments, which will result in earlier recognition of credit losses. Further, the new credit loss model will affect how entities in all industries estimate their allowance for losses for receivables that are current with respect to their payment terms. ASU No. 2018-19 further clarifies that receivables arising from operating leases are not within the scope of Topic 326. Instead, impairment from receivables of operating leases should be accounted for in accordance with Topic 842, Leases. As per the latest ASU 2020-02, FASB deferred the timelines for certain small public and private entities, thus the new guidance will be adopted by the Company for the annual reporting period beginning January 1, 2023, including interim periods within that annual reporting period. The standard will apply as a cumulative-effect adjustment to retained earnings as of the beginning of the first reporting period in which the guidance is adopted. The Company does not expect adoption of this new guidance to have a material impact on its results of operations, financial condition, and financial statement disclosures.

Marketable Securities (Tables)

Marketable Securities (Tables)	3 Months Ended
	Mar. 31, 2022
Investments Debt And Equity Securities [Abstract]
Summary of Marketable Securities	Marketable securities consist of the following as of March 31, 2022 (in thousands): Amortized Cost Unrealized Gains Unrealized Losses Fair Value Commercial paper $ 39,494 $ - $ ( 30 ) $ 39,464 Corporate bonds 81,908 $ 3 $ ( 602 ) $ 81,309 U.S. Government agencies 7,000 $ - $ ( 270 ) $ 6,730 Total $ 128,402 $ 3 $ ( 902 ) $ 127,503

Property and Equipment, Net (Ta

Property and Equipment, Net (Tables)	3 Months Ended
	Mar. 31, 2022
Property Plant And Equipment [Abstract]
Summary of Property and Equipment, Net	Property and equipment, net consist of the following (in thousands): March 31, December 31, Research equipment $ 2,761 $ 4,974 Office equipment and furniture 536 606 Leaseholder improvement 253 253 Total property and equipment 3,550 5,833 Less accumulated depreciation and amortization ( 1,346 ) ( 1,189 ) Property and equipment, net $ 2,204 $ 4,644

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2022
Fair Value Disclosures [Abstract]
Schedule of Financial Assets And Liabilities Measured at Fair Value on Recurring Basis	The following tables present information about the Company’s financial assets and liabilities measured at fair value on a recurring basis and indicate the level of the fair value hierarchy used to determine such fair values (in thousands): Fair value measurements at March 31, 2022 Level 1 Level 2 Level 3 Total Assets: Cash equivalents Money market funds $ 5,248 $ - $ - $ 5,248 Investments: Commercial paper - 39,464 - 39,464 Corporate bonds - 81,309 - 81,309 U.S. Government agencies - 6,730 - 6,730 Total $ 5,248 $ 127,503 $ - $ 132,751

Commitments and Contingencies (

Commitments and Contingencies (Tables)	3 Months Ended
	Mar. 31, 2022
Commitments And Contingencies Disclosure [Abstract]
Summary of Lease Costs Recognized under ASC 842 Pertaining to Finance and Operating Leases	The following table contains a summary of the lease costs recognized under ASC 842 pertaining to the Company’s finance and operating leases for the three months ended March 31, 2022 (in thousands): Three Months Ended March 31, 2022 Lease Cost: Amortization of finance right-of-use assets $ 177 Interest on finance lease liabilities 46 Operating lease cost 414 Variable lease cost 173 Total lease costs $ 810
Summary of Other Information Pertaining to Finance and Operating Leases	The following table contains a summary of other information pertaining to the Company’s finance and operating leases for the three months ended March 31, 2022 (in thousands, except lease term and discount rate): Three Months Ended March 31, 2022 Other Operating Lease Information: Operating cash flows for operating leases $ 392 Operating cash flows for finance leases $ 46 Financing cash flows from finance leases $ 133 Weighted average remaining lease term Operating leases 4.6 years Financing leases 3.7 years Weighted average discount rate Operating leases 7.6 % Financing leases 8.3 %
Supplemental Balance Sheet Information Related to Operating and Financing Leases	The following table presents supplemental balance sheet information related to operating and financing leases as of March 31, 2022 (in thousands): March 31, Operating leases Right-of-use assets $ 6,267 Right-of-use lease liabilities, current $ 1,160 Right-of-use lease liabilities, noncurrent 5,278 Total operating lease liabilities $ 6,438 Financing leases Right-of-use assets, net $ 2,551 Right-of-use lease liabilities, current $ 786 Right-of-use lease liabilities, noncurrent 1,846 Total financing lease liabilities $ 2,632
Summary of Maturity of Operating and Finance Lease Liabilities	The following table presents the maturity of the Company’s operating and finance lease liabilities as of March 31, 2022 (in thousands): Operating Financing Remainder of 2022 $ 1,196 $ 609 2023 1,628 812 2024 1,640 714 2025 1,689 683 2026 1,413 80 Thereafter 59 — Total future minimum lease payments $ 7,625 $ 2,898 Less amount representing interest 1,187 266 Total lease liabilities $ 6,438 $ 2,632
Schedule of Operating Lease Commitments under ASC 840	The following table presents operating lease commitments as reflected under ASC 840 as of December 31, 2021 (in thousands): Operating 2022 1,585 2023 1,606 2024 1,641 2025 1,689 2026 1,413 2027 59 Total operating lease obligations $ 7,993
Schedule of Finance Lease Commitments under ASC 840	The following table presents finance lease commitments as reflected under ASC 840 as of December 31, 2021 (in thousands): Financing 2022 $ 699 2023 674 2024 674 2025 553 2026 47 Total capital lease obligations 2,647 Less amount representing interest ( 293 ) Present value of minimum capital lease obligations $ 2,354

Equity (Tables)

Equity (Tables)	3 Months Ended
	Mar. 31, 2022
Summary of Common Stock Warrant Activity	The following is a summary of the employee-issued common stock warrant activity during the three months ended March 31, 2022: Number Weighted- Weighted- Aggregate Outstanding at December 31, 2021 57,004 $ 6.94 2.91 $ 2 Granted — $ — Exercised — $ — Expired — $ — Outstanding and exercisable at March 31, 2022 57,004 $ 6.94 2.66 $ —
Warrant | Equity and Debt Fundraising Events
Summary of Common Stock Warrant Activity	The following is a summary of the common stock warrant activity related to common stock warrants issued in conjunction with equity and debt fundraising events for the three months ended March 31, 2022: Number Weighted- Weighted- Aggregate Outstanding at December 31, 2021 412,262 $ 9.81 5.71 $ 723 Granted — $ — Exercised — $ — Expired — Outstanding at March 31, 2022 412,262 $ 9.81 5.47 $ —

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2022
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Stock Option Award Activity	The following is a summary of the stock option award activity during the three months ended March 31, 2022: Number Weighted- Weighted- Aggregate Outstanding at December 31, 2021 3,026,464 $ 10.84 8.51 $ 6,403 Granted 681,704 $ 4.05 Exercised ( 73,784 ) $ 3.22 Forfeited ( 206,800 ) $ 9.58 Expired — $ — Outstanding at March 31, 2022 3,427,584 $ 9.73 8.58 $ — Options expected to vest as of March 31, 2022 2,262,393 $ 8.03 9.12 $ — Exercisable at March 31, 2022 1,165,191 $ 13.03 7.53 $ —
Summary of Restricted Stock Unit Activity	The following is a summary of the restricted stock unit activity during the three months ended March 31, 2022: Restricted Stock Units Weighted- Unvested at December 31, 2021 — — Granted 205,201 $ 4.02 Unvested at March 31, 2022 205,201 $ 4.02
Summary of Common Stock Warrant Activity	The following is a summary of the employee-issued common stock warrant activity during the three months ended March 31, 2022: Number Weighted- Weighted- Aggregate Outstanding at December 31, 2021 57,004 $ 6.94 2.91 $ 2 Granted — $ — Exercised — $ — Expired — $ — Outstanding and exercisable at March 31, 2022 57,004 $ 6.94 2.66 $ —
Summary of Fair Value Assumptions and Methodology	The following table presents the assumptions and the Company’s methodology for developing each of the assumptions used: Three Months Ended March 31, 2022 2021 Volatility 93.67 %- 95.8 % 91.5 %- 98.04 % Expected life (years) 5.8 4- 7 5.52 - 6.08 Risk-free interest rate 1.7 %– 2.4 % 0.5 %- 0.1 .0% Dividend rate —% —%
Summary of Stock-Based Compensation Expense	Stock-based compensation expense was recorded in the following line items in the condensed consolidated statements of operations for the three months ended March 31, 2022 and 2021 (in thousands): Three Months Ended March 31, 2022 2021 Research and development $ 555 $ 509 General and administrative 960 840 Total stock-based compensation expense $ 1,515 $ 1,349

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	3 Months Ended
	Mar. 31, 2022
Earnings Per Share [Abstract]
Schedule of Basic and Diluted Net Loss Per Share	Basic and diluted net loss per share attributable to common stockholders is calculated as follows (in thousands except share and per share amounts): Three Months Ended March 31, 2022 2021 Net loss $ ( 12,405 ) $ ( 7,972 ) Net loss attributable to common stockholders $ ( 12,405 ) $ ( 7,972 ) Net loss per share—basic and diluted $ ( 0.40 ) $ ( 0.42 ) Weighted-average number of shares used in computing net loss per share—basic and diluted 30,647,679 18,904,853
Potentially Dilutive Securities Excluded from Calculation of Diluted Net Loss Per Share	The following outstanding potentially dilutive securities have been excluded from the calculation of diluted net loss per share, as their effect is anti-dilutive: For the Three Months Ended March 31, 2022 2021 Stock options to purchase common stock 3,427,584 3,157,199 Unvested restricted stock units 205,201 — Warrants issued to employees and contractor to purchase common stock 57,212 57,212 Warrants issued related to convertible notes and other equity agreements 412,262 412,262

Organization and Operations - A

Organization and Operations - Additional Information (Details) $ / shares in Units, $ in Thousands	Jan. 29, 2021	Feb. 28, 2021USD ($)$ / sharesshares	Mar. 31, 2022USD ($)	Mar. 31, 2021USD ($)shares	Dec. 31, 2021USD ($)
Subsidiary Sale Of Stock [Line Items]
Net loss			$ (12,405)	$ (7,972)
Accumulated deficit			(161,611)		$ (149,206)
Cash, cash equivalents and marketable securities			$ 136,200
Reverse stock split description			On January 29, 2021, the Company effected a reverse stock split of the Company’s common stock on a 48-for-1 basis (the “Reverse Stock Split”).
Reverse stock split conversion ratio	0.020833
Common Stock
Subsidiary Sale Of Stock [Line Items]
Common stock shares issued and sold | shares				8,030,295
IPO | Common Stock
Subsidiary Sale Of Stock [Line Items]
Common stock shares issued and sold | shares		8,030,295
Share price per share | $ / shares		$ 19
Proceeds from issuance initial public offering		$ 152,600
Net proceeds after deducting underwriting discounts and estimated offering expenses		$ 138,500

Summary of Significant Accoun_3

Summary of Significant Accounting Policies - Additional Information (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Jan. 01, 2022
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Operating lease liabilities	$ 6,438
Operating right-of-use assets	$ 6,267
ASC 842
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Operating lease liabilities		$ 6,700
Operating right-of-use assets		6,600
Write-off deferred rent		$ 100

Marketable Securities - Summary

Marketable Securities - Summary of Marketable Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Marketable Securities [Line Items]
Fair Value	$ 127,503	$ 140,462
Marketable Securities
Marketable Securities [Line Items]
Amortized Cost	128,402
Unrealized Gains	3
Unrealized Losses	(902)
Fair Value	127,503
Marketable Securities | Commercial Paper
Marketable Securities [Line Items]
Amortized Cost	39,494
Unrealized Losses	(30)
Fair Value	39,464
Marketable Securities | Corporate Bonds
Marketable Securities [Line Items]
Amortized Cost	81,908
Unrealized Gains	3
Unrealized Losses	(602)
Fair Value	81,309
Marketable Securities | U.S. Government Agencies
Marketable Securities [Line Items]
Amortized Cost	7,000
Unrealized Losses	(270)
Fair Value	$ 6,730

Marketable Securities - Additio

Marketable Securities - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Marketable Securities [Line Items]
Marketable securities, fair value	$ 127,503	$ 140,462
Impairment of investments	0
Corporate Bonds and U.S. Government Agencies
Marketable Securities [Line Items]
Marketable securities, fair value	62,500
Marketable securities, unrealized loss position, fair value	781
Corporate Bonds
Marketable Securities [Line Items]
Marketable securities, unrealized loss position, fair value	$ 118
Minimum | Commercial Paper and U.S. Government Agencies
Marketable Securities [Line Items]
Marketable securities unrealized loss position, maturity term	1 year
Maximum | Commercial Paper
Marketable Securities [Line Items]
Marketable securities remaining maturity term	1 year
Maximum | Corporate Bonds and U.S. Government Agencies
Marketable Securities [Line Items]
Marketable securities remaining maturity term	3 years
Maximum | Corporate Bonds
Marketable Securities [Line Items]
Marketable securities unrealized loss position, maturity term	1 year

Property and Equipment, Net - S

Property and Equipment, Net - Summary of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Property Plant And Equipment [Line Items]
Total property and equipment	$ 3,550	$ 5,833
Less accumulated depreciation and amortization	(1,346)	(1,189)
Property and equipment, net	2,204	4,644
Research Equipment
Property Plant And Equipment [Line Items]
Total property and equipment	2,761	4,974
Office Equipment and Furniture
Property Plant And Equipment [Line Items]
Total property and equipment	536	606
Leaseholder Improvement
Property Plant And Equipment [Line Items]
Total property and equipment	$ 253	$ 253

Property and Equipment, Net - A

Property and Equipment, Net - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Jan. 01, 2022
Property Plant And Equipment [Line Items]
Depreciation and amortization expense	$ 157	$ 98
Right of use assets - financing leases, net	$ 2,551
Research Equipment
Property Plant And Equipment [Line Items]
Right of use assets - financing leases, net			$ 2,200
Office Equipment and Furniture
Property Plant And Equipment [Line Items]
Right of use assets - financing leases, net			$ 70

Other Current Liabilities - Sum

Other Current Liabilities - Summary of Other Current Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Other Liabilities Disclosure [Abstract]
Compensation and employee benefits liabilities	$ 560	$ 1,753

Debt - Additional Information (

Debt - Additional Information (Details) - PPP Loan - USD ($) $ in Thousands	Aug. 06, 2021	May 31, 2020
Debt Instrument [Line Items]
Debt instrument, face amount		$ 567
Debt instrument, interest rate		1.00%
Debt Forgiveness
Debt Instrument [Line Items]
Debt instrument, face amount	$ 567

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Financial Assets And Liabilities Measured at Fair Value on Recurring Basis (Details) - Fair Value Measurements Recurring Basis $ in Thousands	Mar. 31, 2022USD ($)
Assets:
Total	$ 132,751
Level 1
Assets:
Total	5,248
Level 2
Assets:
Total	127,503
Money Market Funds
Assets:
Cash equivalents fair value disclosure	5,248
Money Market Funds | Level 1
Assets:
Cash equivalents fair value disclosure	5,248
Commercial Paper
Assets:
Investments fair value disclosure	39,464
Commercial Paper | Level 2
Assets:
Investments fair value disclosure	39,464
Corporate Bonds
Assets:
Investments fair value disclosure	81,309
Corporate Bonds | Level 2
Assets:
Investments fair value disclosure	81,309
U.S. Government Agencies
Assets:
Investments fair value disclosure	6,730
U.S. Government Agencies | Level 2
Assets:
Investments fair value disclosure	$ 6,730

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair value, transfer of liabilities, from level 1 to level 2	$ 0	$ 0
Fair value, transfer of liabilities from level 2 to level 1	0	0
Fair value, transfer of assets into level 3	0	0
Fair value, transfer of assets out of level 3	0	0
Fair value, transfer of liabilities into level 3	0	0
Fair value, transfer of liabilities out of level 3	$ 0	$ 0

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details)	Oct. 01, 2021USD ($)ft²	Sep. 27, 2021USD ($)	May 14, 2021USD ($)ft²	Apr. 20, 2021USD ($)	Nov. 01, 2020USD ($)ft²	Mar. 31, 2022USD ($)	Mar. 31, 2021USD ($)	Dec. 31, 2017USD ($)Officer	Dec. 31, 2021USD ($)
Sale Leaseback Transaction [Line Items]
Lease expiration year						2027
Leased space, in square feet | ft²	4,258		10,082		7,643
Base monthly rent during first 12 months of lease	$ 33,000		$ 69,000		$ 25,000
Percentage increase on base monthly rent	3.00%		3.00%		3.00%
Lease expiration date					Feb. 28, 2027	Sep. 30, 2026
Lease renew term						5 years
Letters of credit agreements outstanding amount					$ 50,000	$ 628,000
Finance lease, term				4 years
Capital lease payments						133,000	$ 10,000
Sale of equipment				$ 293,000
Gain on sale of equipment				$ 20,000
Property and equipment, net						2,204,000			$ 4,644,000
Available for purchases of property and equipment						$ 2,700,000
Percentage of equipment cost				15.00%
Number of former officers | Officer								2
Loss contingency allegations claims								$ 0
Loss contingency, allegations						The Company believes that there is no merit to the claims alleged against the Company and its former officers, including no alleged breach of contract by the Company, and intends to vigorously defend against the claims pertaining to the Company and its former officers.
Minimum
Sale Leaseback Transaction [Line Items]
Additional renew of lease term				1 year
Maximum
Sale Leaseback Transaction [Line Items]
Additional renew of lease term				2 years
Research Equipment
Sale Leaseback Transaction [Line Items]
Finance lease, term		4 years
Lease payment, term		monthly
Capital lease payments		$ 13,000
Equipment | Maximum
Sale Leaseback Transaction [Line Items]
Property and equipment, net				$ 5,000,000

Commitments and Contingencies_2

Commitments and Contingencies - Summary of Lease Costs Recognized under ASC 842 Pertaining to Finance and Operating Leases (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Lease Cost:
Amortization of finance right-of-use assets	$ 177
Interest on finance lease liabilities	46	$ 3
Operating lease cost	414
Variable lease cost	173
Total lease costs	$ 810

Commitments and Contingencies_3

Commitments and Contingencies - Summary of Other Information Pertaining to Finance and Operating Leases (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Other Operating Lease Information:
Operating cash flows for operating leases	$ 392
Operating cash flows for finance leases	46
Financing cash flows from finance leases	$ 133	$ 10
Weighted average remaining lease term
Operating leases	4 years 7 months 6 days
Financing leases	3 years 8 months 12 days
Weighted average discount rate
Operating leases	7.60%
Financing leases	8.30%

Commitments and Contingencies_4

Commitments and Contingencies - Supplemental Balance Sheet Information Related to Operating and Financing Leases (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Operating leases
Right-of-use assets	$ 6,267
Right-of-use lease liabilities, current	1,160
Right-of-use lease liabilities, noncurrent	5,278
Total operating lease liabilities	6,438
Financing leases
Right-of-use assets, net	2,551
Right-of-use lease liabilities, current	786	$ 680
Right-of-use lease liabilities, noncurrent	1,846	$ 1,674
Total financing lease liabilities	$ 2,632

Commitments and Contingencies_5

Commitments and Contingencies - Summary of Maturity of Operating and Finance Lease Liabilities (Details) $ in Thousands	Mar. 31, 2022USD ($)
Operating
Remainder of 2022	$ 1,196
2023	1,628
2024	1,640
2025	1,689
2026	1,413
Thereafter	59
Total future minimum lease payments	7,625
Less amount representing interest	1,187
Total lease liabilities	6,438
Financing
Remainder of 2022	609
2023	812
2024	714
2025	683
2026	80
Total future minimum lease payments	2,898
Less amount representing interest	266
Total lease liabilities	$ 2,632

Commitments and Contingencies_6

Commitments and Contingencies - Schedule of Operating Lease Commitments under ASC 840 (Details) $ in Thousands	Dec. 31, 2021USD ($)
Commitments And Contingencies Disclosure [Abstract]
2022	$ 1,585
2023	1,606
2024	1,641
2025	1,689
2026	1,413
2027	59
Total operating lease obligations	$ 7,993

Commitments and Contingencies_7

Commitments and Contingencies - Schedule of Finance Lease Commitments under ASC 840 (Details) $ in Thousands	Dec. 31, 2021USD ($)
Commitments And Contingencies Disclosure [Abstract]
2022	$ 699
2023	674
2024	674
2025	553
2026	47
Total capital lease obligations	2,647
Less amount representing interest	(293)
Present value of minimum capital lease obligations	$ 2,354

Equity - Additional Information

Equity - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	Feb. 08, 2021	Feb. 28, 2021	Jan. 31, 2021	Mar. 31, 2022	Dec. 31, 2021
Class Of Stock [Line Items]
Common stock, shares authorized				250,000,000	250,000,000
IPO
Class Of Stock [Line Items]
Common stock shares issued and sold		8,030,295
Partial exercise of the underwriters option to purchase additional shares		1,030,243
Sale of Stock, Price Per Share		$ 19
Aggregate gross proceeds from issuance of initial public offering		$ 152.6
Net proceeds after deducting underwriting discounts		$ 138.5
Outstanding preferred stock converted into aggregate shares of common stock	19,034,069
Common stock, shares authorized	250,000,000
Preferred stock, shares authorized	10,000,000
Series BB Convertible Preferred Stock Issuance
Class Of Stock [Line Items]
Convertible preferred stock shares issued and sold			113,275,902
Convertible preferred stock per share			$ 0.207383
Proceeds on the issuance of convertible preferred stock			$ 23.5

Equity - Summary of Common Stoc

Equity - Summary of Common Stock Warrant activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Class Of Stock [Line Items]
Number of Common Stock Warrants Outstanding, Beginning Balance	57,004
Number of Common Stock Warrants Outstanding, Ending Balance		57,004
Weighted-Average Exercise Price Outstanding, Beginning Balance	$ 6.94
Weighted-Average Exercise Price Outstanding, Ending Balance		$ 6.94
Weighted-Average Remaining Contractual Term, Outstanding		2 years 10 months 28 days
Aggregate Intrinsic Value Outstanding		$ 2
Warrant | Equity and Debt Fundraising Events
Class Of Stock [Line Items]
Number of Common Stock Warrants Outstanding, Beginning Balance	412,262
Number of Common Stock Warrants Outstanding, Ending Balance	412,262	412,262
Weighted-Average Exercise Price Outstanding, Beginning Balance	$ 9.81
Weighted-Average Exercise Price Outstanding, Ending Balance	$ 9.81	$ 9.81
Weighted-Average Remaining Contractual Term, Outstanding	5 years 5 months 19 days	5 years 8 months 15 days
Aggregate Intrinsic Value Outstanding		$ 723

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Jan. 01, 2022	Jan. 27, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Recognized share-based compensation expense	$ 1,515,000	$ 1,349,000
Grant dates at weighted average fair value	$ 4.05
Aggregate intrinsic value of stock options exercised	$ 100,000
Options vested	$ 4,100,000
Options available for grant	681,704
Unrecognized stock-based compensation expense	$ 15,200,000
Weighted-average period	2 years 10 months 13 days
Common Stock Warrants
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized stock-based compensation expense	$ 0
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average period	3 years 7 months 17 days
Unrecognized stock-based compensation expense	$ 800,000
2021 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserved for issuance	2,504,400		5,000,000
Number of capital stock outstanding percentage	4.00%
Grant dates at weighted average fair value	$ 3.13
2021 Equity Incentive Plan | Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock units vested	0
2021 Equity Incentive Plan | Restricted Stock Units | Vesting Period One
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	1 year
2021 Equity Incentive Plan | Restricted Stock Units | Vesting Period Two
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	2 years
2021 Equity Incentive Plan | Restricted Stock Units | Vesting Period Three
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	4 years
2021 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserved for issuance	627,723			333,333
Percentage of number of shares of capital stock outstanding on last day of preceding year	1.00%
Recognized share-based compensation expense	$ 0
Purchase price of fair value common stock, percent	85.00%
Stock issued under plan	11,700

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Stock Option Award Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Number of Stock Options, Outstanding balance	3,026,464
Number of Stock Options, Granted	681,704
Number of Stock Options, Exercised	(73,784)
Number of Stock Options, Forfeited	(206,800)
Number of Stock Options, Outstanding balance	3,427,584	3,026,464
Number of Stock Options, Options expected to vest	2,262,393
Number of Stock Options, Exercisable	1,165,191
Weighted-Average Exercise Price, Outstanding balance	$ 10.84
Grant dates at weighted average fair value	4.05
Weighted-Average Exercise Price, Exercised	3.22
Weighted-Average Exercise Price, Forfeited	9.58
Weighted-Average Exercise Price,Outstanding balance	9.73	$ 10.84
Weighted-Average Exercise Price, Options expected to vest	8.03
Weighted-Average Exercise Price, Exercisable	$ 13.03
Weighted-Average Remaining Contractual Term, Outstanding balance	8 years 6 months 29 days	8 years 6 months 3 days
Weighted-Average Remaining Contractual Term, Exercisable	7 years 6 months 10 days
Weighted-Average Remaining Contractual Term, Options expected to vest	9 years 1 month 13 days
Aggregate Intrinsic Value, Outstanding		$ 6,403

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of Restricted Stock Unit Activity (Details) - Restricted Stock Units	3 Months Ended
	Mar. 31, 2022$ / sharesshares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted Stock Units, Granted | shares	205,201
Restricted Stock Units, Unvested balance | shares	205,201
Weighted-Average Grant Date Fair Value, Granted | $ / shares	$ 4.02
Weighted-Average Grant Date Fair Value, Unvested balance | $ / shares	$ 4.02

Stock-Based Compensation - Su_3

Stock-Based Compensation - Summary of Employee-issued Common Stock Warrant Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Number of Common Stock Warrants Outstanding, Beginning Balance	57,004
Number of Common Stock Warrants Outstanding and Exercisable, Ending Balance	57,004
Weighted-Average Exercise Price Outstanding, Beginning Balance	$ 6.94
Weighted-Average Exercise Price Outstanding and Exercisable, Ending Balance	$ 6.94
Weighted-Average Remaining Contractual Term Outstanding		2 years 10 months 28 days
Weighted-Average Remaining Contractual Term Outstanding and Exercisable	2 years 7 months 28 days
Aggregate Intrinsic Value Outstanding		$ 2

Stock-Based Compensation - Su_4

Stock-Based Compensation - Summary of Fair Value Assumptions and Methodology (Details)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Volatility, Minimum	93.67%	91.50%
Volatility, Maximum	95.80%	98.04%
Risk-free interest rate, Minimum	1.70%	0.50%
Risk-free interest rate, Maximum	2.40%	0.10%
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected life (years)	5 years 9 months 18 days	5 years 6 months 7 days
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected life (years)	7 years	6 years 29 days

Stock-Based Compensation - Su_5

Stock-Based Compensation - Summary of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 1,515	$ 1,349
Research and Development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	555	509
General and Administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 960	$ 840

Employee Retirement Plan - Addi

Employee Retirement Plan - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Company's matching contributions vesting percentage	100.00%
Accrued expense	$ 106	$ 29
Maximum
Defined Benefit Plan Disclosure [Line Items]
Percentage of company matching contributions of employee's base salary	4.00%

Related-Party Transactions - Ad

Related-Party Transactions - Additional Information (Details) - Service Agreement - Hope Farms - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Related Party Transaction [Line Items]
Consultation service fee payment	$ 28	$ 52
Due to related party		$ 47

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2020
Income Tax Disclosure [Abstract]
Provision for income taxes	$ 0	$ 0

Net Loss Per Share - Schedule o

Net Loss Per Share - Schedule of Basic and Diluted Net Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Earnings Per Share [Abstract]
Net loss	$ (12,405)	$ (7,972)
Net loss attributable to common stockholders	$ (12,405)	$ (7,972)
Net loss per share-basic and diluted	$ (0.40)	$ (0.42)
Weighted-average number of shares used in computing net loss per common share, basic and diluted	30,647,679	18,904,853

Net Loss Per Share - Potentiall

Net Loss Per Share - Potentially Dilutive Securities Excluded from Calculation of Diluted Net Loss Per Share (Details) - shares	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Stock Options to Purchase Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from calculation of diluted net loss per share	3,427,584	3,157,199
Unvested Restricted Stock Units
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from calculation of diluted net loss per share	205,201
Warrants Issued to Employees and Contractor to Purchase Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from calculation of diluted net loss per share	57,212	57,212
Warrants Issued Related to Convertible Notes and Other Equity Agreements
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from calculation of diluted net loss per share	412,262	412,262