Acumen Pharmaceuticals (ABOS) 10-Q14 Nov 222022 Q3 Quarterly reportFinancial data

Company Profile

Cover Page

Cover Page - shares	9 Months Ended
Cover Page - shares	Sep. 30, 2022	Nov. 11, 2022
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Entity Registrant Name	Acumen Pharmaceuticals, Inc.
Entity Central Index Key	0001576885
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2022
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q3
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	001-40551
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	36-4108129
Entity Address, Address Line One	427 Park St.
Entity Address, City or Town	Charlottesville
Entity Address, State or Province	VA
Entity Address, Postal Zip Code	22902
City Area Code	434
Local Phone Number	297-1000
Title of 12(b) Security	Common stock, par value $0.0001 per share
Trading Symbol	ABOS
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		40,925,284

Condensed Balance Sheets

Condensed Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Current assets
Cash and cash equivalents	$ 157,540	$ 122,162
Marketable securities, short-term	42,654	72,075
Prepaid expenses and other current assets	2,366	4,424
Total current assets	202,560	198,661
Marketable securities, long-term		31,619
Property and equipment, net	142	36
Deferred offering costs	337
Right-of-use asset	133
Other assets	92	14
Total assets	203,264	230,330
Current liabilities
Accounts payable	2,084	1,088
Accrued expenses and other current liabilities	4,396	4,059
Operating lease liability, current portion	133
Total current liabilities	6,613	5,147
Total liabilities	6,613	5,147
Commitments and contingencies (Note 9)
Stockholders' equity
Preferred stock, $0.0001 par value; 10,000,000 shares authorized and no shares issued and outstanding as of September 30, 2022 and December 31, 2021
Common stock, $0.0001 par value; 300,000,000 shares authorized and 40,503,124 and 40,473,270 shares issued and outstanding as of September 30, 2022 and December 31, 2021, respectively	4	4
Additional paid-in capital	355,173	352,981
Accumulated deficit	(157,561)	(127,571)
Accumulated other comprehensive loss	(965)	(231)
Total stockholders' equity	196,651	225,183
Total liabilities and stockholders' equity	$ 203,264	$ 230,330

Condensed Balance Sheets (Paren

Condensed Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2022	Dec. 31, 2021
Preferred stock, par or stated value per share	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred Stock, Shares Issued	0	0
Preferred Stock, Shares Outstanding	0	0
Common Stock Par Value	$ 0.0001	$ 0.0001
Common Shares Authorized	300,000,000	300,000,000
Common Shares Issued	40,503,124	40,473,270
Common Shares Outstanding	40,503,124	40,473,270

Condensed Statements of Operati

Condensed Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Operating expenses
Research and development	$ 8,309	$ 1,800	$ 21,615	$ 6,632
General and administrative	3,062	2,135	9,374	4,537
Total operating expenses	11,371	3,935	30,989	11,169
Loss from operations	(11,371)	(3,935)	(30,989)	(11,169)
Other income (expense)
Change in fair value of preferred stock tranche rights liability and preferred stock warrant liability				(81,157)
Interest income, net	663	14	1,000	22
Other income, net	(2)	19	(1)	47
Total other income (expense)	661	33	999	(81,088)
Net loss	(10,710)	(3,902)	(29,990)	(92,257)
Other comprehensive loss
Unrealized loss on marketable securities		(28)	(734)	(28)
Comprehensive loss	$ (10,710)	$ (3,930)	$ (30,724)	$ (92,285)
Net loss per common share, basic	$ (0.26)	$ (0.1)	$ (0.74)	$ (7)
Net loss per common share, diluted	$ (0.26)	$ (0.1)	$ (0.74)	$ (7)
Weighted-average shares outstanding, basic	40,502,860	38,266,593	40,491,181	13,177,983
Weighted-average shares outstanding, diluted	40,502,860	38,266,593	40,491,181	13,177,983

Condensed Statements of Changes

Condensed Statements of Changes in Convertible Preferred Stock and Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Series A Convertible Preferred Stock [Member]	Series A-1 Convertible Preferred Stock [Member]	Series B Convertible Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Loss
Opening balance at Dec. 31, 2020		$ 1,067	$ 16,333	$ 39,253
Opening balance at Dec. 31, 2020	$ (18,591)				$ 0	$ 8,374	$ (26,965)	$ 0
Opening balance (Shares) at Dec. 31, 2020		477,297	7,537,879	11,862,043	419,124
Unrealized loss on marketable securities	(28)							(28)
Stock options exercised for cash	2					2
Stock options exercised for cash, Shares					2,236
Cashless stock options exercise (shares)					178,847
Stock-based compensation	557					557	0	0
Issuance of milestone shares for cash, net of issuance costs				$ 30,031
Issuance of milestone shares for cash, net of issuance costs (Shares)				7,908,027
Exercise of preferred stock warrant			$ 1,250
Exercise of preferred stock warrant (shares)			447,426
Reclassification of preferred stock tranche rights liability upon issuance of milestone shares				$ 81,190
Reclassification of warrant liability upon exercise of preferred stock warrant	5,380		$ 5,380
Exercise of common stock warrants	614					614		0
Exercise of common stock warrants (Shares)					137,446
Conversion of convertible preferred stock into common stock upon initial public offering	174,504	$ (1,067)	$ (22,963)	$ (150,474)	$ 3	174,501
Conversion of convertible preferred stock into common stock upon initial public offering, Shares		(477,297)	(7,985,305)	(19,770,070)	28,232,672
Issuance of common stock for cash, net of issuance costs of $15,441	168,559				$ 1	168,558
Issuance of common stock for cash, net of issuance costs of $15,441, Shares					11,499,998
Net loss	(92,257)						(92,257)	0
Closing balance at Sep. 30, 2021		$ 0	$ 0	$ 0
Closing balance at Sep. 30, 2021	233,360				$ 4	352,606	(119,222)	(28)
Closing balance (Shares) at Sep. 30, 2021		0	0	0	40,470,323
Opening balance at Jun. 30, 2021		$ 1,067	$ 22,963	$ 150,474
Opening balance at Jun. 30, 2021	(106,079)				$ 0	9,241	(115,320)	0
Opening balance (Shares) at Jun. 30, 2021		477,297	7,985,305	19,770,070	556,570
Unrealized loss on marketable securities	(28)							(28)
Stock options exercised for cash	2					2
Stock options exercised for cash, Shares					2,236
Cashless stock options exercise (shares)					178,847
Stock-based compensation	304					304	0	0
Conversion of convertible preferred stock into common stock upon initial public offering	174,504	$ (1,067)	$ (22,963)	$ (150,474)	$ 3	174,501
Conversion of convertible preferred stock into common stock upon initial public offering, Shares		(477,297)	(7,985,305)	(19,770,070)	28,232,672
Issuance of common stock for cash, net of issuance costs of $15,441	168,559				$ 1	168,558
Issuance of common stock for cash, net of issuance costs of $15,441, Shares					11,499,998
Net loss	(3,902)						(3,902)	0
Closing balance at Sep. 30, 2021		$ 0	$ 0	$ 0
Closing balance at Sep. 30, 2021	233,360				$ 4	352,606	(119,222)	(28)
Closing balance (Shares) at Sep. 30, 2021		0	0	0	40,470,323
Opening balance at Dec. 31, 2021	225,183				$ 4	352,981	(127,571)	(231)
Opening balance (Shares) at Dec. 31, 2021					40,473,270
Unrealized loss on marketable securities	(734)							(734)
Stock options exercised for cash	$ 19					19
Stock options exercised for cash, Shares	31,848				25,108
Cashless stock options exercise (shares)					4,746
Stock-based compensation	$ 2,173					2,173
Net loss	(29,990)						(29,990)
Closing balance at Sep. 30, 2022	196,651				$ 4	355,173	(157,561)	(965)
Closing balance (Shares) at Sep. 30, 2022					40,503,124
Opening balance at Jun. 30, 2022	206,519				$ 4	354,331	(146,851)	(965)
Opening balance (Shares) at Jun. 30, 2022					40,501,258
Stock options exercised for cash	2					2
Stock options exercised for cash, Shares					1,866
Stock-based compensation	840					840
Net loss	(10,710)						(10,710)
Closing balance at Sep. 30, 2022	$ 196,651				$ 4	$ 355,173	$ (157,561)	$ (965)
Closing balance (Shares) at Sep. 30, 2022					40,503,124

Condensed Statements of Chang_2

Condensed Statements of Changes in Convertible Preferred Stock and Stockholders' Equity (Deficit) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2021
Common Stock [Member]
Stock issuance Costs	$ 15,441	$ 15,441
Series B Convertible Preferred Stock [Member]
Stock issuance Costs		$ 16

Condensed Statements of Cash Fl

Condensed Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
Condensed Statements of Cash Flows - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Cash flows from operating activities
Net loss	$ (29,990)	$ (92,257)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	20	1
Change in fair value of preferred stock tranche rights liability and preferred stock warrant liability		81,157
Stock-based compensation expense	2,173	557
Amortization of premiums and accretion of discounts on marketable securities, net	575	(6)
Amortization of right-of-use asset	100
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	2,058	(4,297)
Other assets	(78)	(13)
Accounts payable	996	(149)
Operating lease liability	(100)
Accrued expenses and other current liabilities	296	685
Net cash used in operating activities	(23,950)	(14,322)
Cash flows from investing activities
Purchases of marketable securities	(12,129)	(94,095)
Proceeds from maturities and sales of marketable securities	71,860
Purchases of property and equipment	(126)	(14)
Net cash provided by (used in) investing activities	59,605	(94,109)
Cash flows from financing activities
Proceeds from issuance of Series B milestone shares, net of issuance costs		30,031
Proceeds from issuance of common stock upon initial public offering, net of offering costs		168,559
Payment of deferred offering costs	(296)
Proceeds from the exercise of stock options	19	2
Net cash provided by (used in) financing activities	(277)	200,456
Net change in cash and cash equivalents	35,378	92,025
Cash and cash equivalents at the beginning of the period	122,162	43,777
Cash and cash equivalents at the end of the period	157,540	135,802
Supplemental disclosure of noncash investing and financing activities
Right-of-use asset obtained in exchange for operating lease liabilities	233
Deferred offering costs in accrued expenses and other current liabilities	41	0
Reclassification of preferred stock tranche rights liability upon share issuance	0	81,190
Conversion of convertible preferred stock into common stock upon initial public offering	0	174,504
Reclassification of warrant liability upon exercise of preferred stock warrant		5,380
Series A -1 Convertible Preferred Stock Warrant Liability [Member]
Cash flows from financing activities
Proceeds from exercise of warrants		1,250
Common Stock Warrants [Member]
Cash flows from financing activities
Proceeds from exercise of warrants		$ 614

Description of Organization and

Description of Organization and Business Operations	9 Months Ended
Description of Organization and Business Operations	Sep. 30, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Organization and Business Operations	NOTE 1. DESCRIPTION OF ORGANIZATION AND BUSINESS OPERATIONS Acumen Pharmaceuticals, Inc. (“Acumen” or the “Company”) was incorporated in 1996 in the state of Delaware. Acumen is a clinical-stage biopharmaceutical company developing a novel disease-modifying approach to target what the Company believes to be a key underlying cause of Alzheimer’s disease (“AD”). Acumen’s sole drug candidate, ACU193, is a humanized monoclonal antibody which selectively targets amyloid-beta oligomers. The Company is subject to the uncertainty of whether the Company’s intellectual property will develop into successful commercial products. June 2021 Reverse Stock Split The Company’s Board of Directors (“Board”) approved a reverse split of shares of the Company’s common stock and convertible preferred stock on a 1-for-1.49 basis Initial Public Offering On July 6, 2021, the Company issued 9,999,999 shares of common stock in an initial public offering (“IPO”), and on July 8, 2021, the Company issued an additional 1,499,999 shares of common stock that were purchased by the underwriters pursuant to the underwriters’ option to purchase additional shares at the public offering price less underwriting discounts and commissions. The price to the public for each share was $16.00. The aggregate net proceeds from the Company’s IPO, after underwriting discounts and commissions and other offering expenses of $15.4 million, were $168.6 million. On July 6, 2021, in connection with the closing of the IPO, 477,297 shares of Series A, 7,985,305 shares of Series A-1, As a result of the IPO, the underwriters’ exercise of their option, the conversions of the Series A, A-1 stock shares Liquidity and Capital Resources The Company has incurred operating losses since inception and expects to continue to incur significant operating losses for the foreseeable future and may never become profitable. As of September 30, 2022 and December 31, 2021, the Company had an accumulated deficit of $157.6 million and $127.6 million, respectively, and working capital of $195.9 million and $193.5 million, respectively. Management believes that the Company has sufficient cash to continue operating activities for beyond 12 months from issuance of these condensed financial statements. Future capital requirements will depend upon many factors, including the timing and extent of spending on research and development and market acceptance of the Company’s products. The Company may need to obtain additional financing to complete clinical trials and launch and commercialize any product candidates for which it receives regulatory approval. Until such time, if ever, the Company can generate revenue sufficient to achieve profitability, the Company expects to finance its operations through a combination of equity offerings, debt financings, collaborations, strategic alliances and licensing arrangements. There can be no assurance that such financing will be available on terms acceptable to the Company, or at all. To the extent that the Company raises additional capital through the sale of equity or convertible debt securities, the ownership interest of its stockholders will be diluted, and the terms of these securities may include liquidation of other preferences that adversely affect the rights of common stockholders. Debt financing and preferred equity financing, if available, may involve agreements that include covenants limiting or restricting the Company’s ability to take specific actions, such as incurring additional debt, making acquisitions or capital expenditures or declaring dividends. If the Company is unable to maintain sufficient financial resources, its business, financial condition and results of operations will be materially and adversely affected. The Company may be required to delay, limit, reduce or terminate its product discovery and development activities or future commercialization efforts. The Company initiated a Phase 1 clinical trial of ACU193 in 2021, which the Company named “INTERCEPT-AD.” in the INTERCEPT-AD trial (“COVID-19”) pandemic, the The Company anticipates completing enrollment in INTERCEPT-AD in the first quarter of 2023 . The Company’s business, results of operations, financial position and cash flows will depend on future developments, including the duration and spread of the COVID-19 of the COVID-19 pandemic,

Basis of Presentation, Summary

Basis of Presentation, Summary of Significant Accounting Policies and Recent Accounting Pronouncements	9 Months Ended
	Sep. 30, 2022
Accounting Policies [Abstract]
Basis of Presentation, Summary of Significant Accounting Policies and Recent Accounting Pronouncements	NOTE 2. BASIS OF PRESENTATION, SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES AND RECENT ACCOUNTING PRONOUNCEMENTS Basis of Presentation The accompanying unaudited condensed financial statements have been prepared in accordance with Generally Accepted Accounting Principles in the United States of America (“U.S. GAAP”) for interim financial information, the instructions to Form 10-Q S-X. A description of the Company’s significant accounting policies is included in the Company’s Annual Report. Other than as described below, there have been no material changes in the Company’s significant accounting policies to those previously disclosed in the Company’s Annual Report. Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the unaudited condensed financial statements, as well as the reported amounts of expenses during the reporting periods. These estimates and assumptions are based on the Company’s historical experience, and on various other factors that management believes are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities and the recording of expenses that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions. To the extent there are material differences between the estimates and actual results, the Company’s future results of operations will be affected. Reclassifications Certain prior year amounts have been reclassified for consistency with the current period presentation. Interest income and interest expense are combined into one line item and presented net in the condensed statements of operations and comprehensive loss, whereas these line items were previously presented separately. Similarly, in the condensed statements of cash flows, amortization of premiums and accretion of discounts on marketable securities are now presented net, but previously had been presented on separate rows as amortization of premiums and non-cash Leases The Company accounts for its leases under Accounting Standards Codification (“ASC”) 842, Leases right-of-use right-of-use right-of-use right-of-use ASC 842 provides practical expedients for an entity’s ongoing accounting. In calculating right-of-use non-lease right-of-use Recently Adopted Accounting Pronouncements ASC 842 requires lessees to recognize the liabilities related to all leases, including operating leases, with a term greater than 12 months on the balance sheet and also requires lessees and lessors to disclose key information about their leasing transactions. The Company adopted this guidance on January 1, 2022, using the modified retrospective method and the Company elected the package of practical expedients upon transition, which retained the lease classification for leases that existed prior to the adoption of this guidance. The Company recorded both a right-of-use In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes 2019-12”), 2019-12 Recently Issued Accounting Pronouncements In June 2016, the FASB issued ASU 2016-13, Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments available-for-sale

Marketable Securities

Marketable Securities	9 Months Ended
Marketable Securities	Sep. 30, 2022
Marketable Securities [Abstract]
Marketable Securities	NOTE 3. MARKETABLE SECURITIES Marketable securities consisted of the following as of September 30, 2022 and December 31, 2021 (in thousands): September 30, 2022 Amortized Gross Gross Fair Available-for-sale Corporate debt securities $ 16,531 $ — $ (369 ) $ 16,162 Asset-backed securities 3,008 — (120 ) 2,888 U.S. treasury securities 24,080 — (476 ) 23,604 Total available-for-sale 43,619 — (965 ) 42,654 Total available-for-sale $ 43,619 $ — $ (965 ) $ 42,654 December 31, 2021 Amortized Gross Gross Fair Value Available-for-sale Commercial paper $ 47,939 $ — $ — $ 47,939 Corporate debt securities 7,992 — (11 ) 7,981 Asset-backed securities 16,177 — (22 ) 16,155 Total available-for-sale 72,108 — (33 ) 72,075 Available-for-sale Corporate debt securities 16,816 — (103 ) 16,713 Asset-backed securities 3,013 — (25 ) 2,988 U.S. treasury securities 11,988 — (70 ) 11,918 Total available-for-sale 31,817 — (198 ) 31,619 Total available-for-sale $ 103,925 $ — $ (231 ) $ 103,694 As of September 30, 2022, the Company’s available-for-sale were available-for-sale that were available-for-sale

Fair Value Measurements

Fair Value Measurements	9 Months Ended
Fair Value Measurements	Sep. 30, 2022
Fair Value Disclosures [Abstract]
Fair Value Measurements	NOTE 4. FAIR VALUE MEASUREMENTS The Company’s financial assets and liabilities subject to fair value measurement on a recurring basis and the level of inputs used for such measurements were as follows (in thousands): Fair value measurements at reporting date using Quoted Prices in Significant Other Significant Fair Value at Assets included in: Cash and cash equivalents Money market securities $ 156,540 $ — $ — $ 156,540 Marketable securities Corporate debt securities — 16,162 — 16,162 Asset-backed securities — 2,888 — 2,888 U.S. treasury securities — 23,604 — 23,604 Total fair value $ 156,540 $ 42,654 $ — $ 199,194 Fair value measurements at reporting date using Quoted Prices in Significant Other Significant Unobservable Fair Value at Assets included in: Cash and cash equivalents Money market securities $ 121,162 $ — $ — $ 121,162 Marketable securities Commercial paper — 47,939 — 47,939 Corporate debt securities — 24,694 — 24,694 Asset-backed securities — 19,143 — 19,143 U.S. treasury securities — 11,918 — 11,918 Total fair value $ 121,162 $ 103,694 $ — $ 224,856 The carrying values reported in the Company’s condensed balance sheets for cash (excluding cash equivalents which are recorded at fair value on a recurring basis), accounts payable and accrued expenses are reasonable estimates of their fair values due to the short-term nature of these items. The fair value of the Company’s money market funds is determined using quoted market prices in active markets for identical assets. The fair value for the available-for-sale

Supplemental Financial Informat

Supplemental Financial Information	9 Months Ended
Supplemental Financial Information	Sep. 30, 2022
Supplemental Financial Information [Abstract]
Supplemental Financial Information	NOTE 5. SUPPLEMENTAL FINANCIAL INFORMATION Prepaid expenses and other current assets consisted of the following (in thousands): September 30, 2022 December 31, 2021 Prepaid insurance $ 1,666 $ 1,514 Prepaid raw materials 201 83 Research and development service agreements 172 2,591 Dues and subscriptions 121 96 Other 206 140 Total prepaid expenses and other current assets $ 2,366 $ 4,424 Accrued expenses and other current liabilities consisted of the following (in thousands): September 30, 2022 December 31, 2021 Research and development $ 2,837 $ 2,623 Compensat ion 1,455 1,102 Legal 67 130 Other 37 204 Total accrued expenses and other current liabilities $ 4,396 $ 4,059

Stockholders' Equity

Stockholders' Equity	9 Months Ended
Stockholders' Equity	Sep. 30, 2022
Stockholders' Equity Note [Abstract]
Stockholders' Equity	NOTE 6. STOCKHOLDERS’ EQUITY Authorized Shares The total number of shares of all classes of capital stock authorized to be issued is 310,000,000, with 10,000,000 shares designated as preferred stock with a par value of $0.0001, and 300,000,000 shares designated as common stock with a par value of $0.0001. Common Stock As of September 30, 2022, the Company’s Amended and Restated Certificate of Incorporation authorized the issuance of 300,000,000 shares of common stock, $0.0001 par value per share. Each share of common stock is entitled to one voting right. Shelf Registration and At-The-Market On July 1, 2022, the Company filed a shelf registration statement on Form S-3 at-the-market program (the “ATM”), which is included in the $200.0 million of securities that may be offered pursuant to the Registration Statement. Pursuant to the ATM, the Company will pay the Sales Agents a commission rate of up to the gross proceeds from the sale of any shares of common stock. The Company is not obligated to make any sales of shares of its common stock under the ATM. The Company had not sold any shares of its common stock under the ATM as of September 30, 2022.

Stock-Based Compensation

Stock-Based Compensation	9 Months Ended
Stock-Based Compensation	Sep. 30, 2022
Share-based Payment Arrangement [Abstract]
Stock-Based Compensation	NOTE 7. STOCK-BASED COMPENSATION 2021 Equity Incentive Plan The 2021 Equity Incentive Plan (the “2021 Plan”), which provides for the grant of incentive stock options to employees, and 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, became effective on June 30, 2021. The 2021 Plan is a successor to the Company’s Amended and Restated Stock Performance Plan that was adopted by the Board and stockholders on April 8, 2013 (as amended from time to time, most recently on November 20, 2020, the “2013 Plan”). Following the effectiveness of the 2021 Plan, no further grants may be made under the 2013 Plan; however, any outstanding equity awards granted under the 2013 Plan continue to be governed by the terms of the 2013 Plan. Initially, the maximum number of shares of the Company’s common stock that may be issued under the 2021 Plan was 7,698,282 shares, which is the sum of (1) 3,550,000 new shares, plus (2) 667,104 shares that remained available for issuance under the Company’s 2013 Plan at the time the 2021 Plan became effective, plus (3) any shares subject to outstanding stock options or other stock awards that were granted under the 2013 Plan that, on or after the 2021 Plan became effective, terminate or expire prior to exercise or settlement, are settled in cash, are forfeited or repurchased because of the failure to vest, or are reacquired or withheld to satisfy a tax withholding obligation or the purchase or exercise price in accordance with the terms of the 2013 Plan. In addition, the number of shares of the Company’s common stock reserved for issuance under the 2021 Plan will automatically increase on January 1 of each calendar year, starting on January 1, 2022 through January 1, 2031, in an amount equal to 5% of the total number of shares of the Company’s common stock outstanding on December 31 of the fiscal year before the date of each automatic increase, or a lesser number of shares determined by the Board prior to the applicable January 1. On January 1, 2022, the Board increased the number of shares of common stock reserved for issuance under the 2021 Plan by 2,023,663 shares. The maximum number of shares of the Company’s common stock that may be issued upon the exercise of incentive stock options under the 2021 Plan is 12,000,000. As of September 30, 2022, 9,721,945 shares were authorized for issuance under the 2021 Plan and 4,030,960 shares remained available for issuance under the 2021 Plan. Stock Options The Black-Scholes option-pricing model was used to estimate the fair value of stock options granted during the nine months ended September 30, 2022 and 2021 with the following weighted average assumptions: Nine Months Ended September 30, 2022 2021 Risk-free interest rate 1.71% - 4.17% 0.4% - 1.1% Expected term (in years) 5.8 - 6.1 5.3 - 6.1 Expected volatility 90% 90% Expected dividend yield 0% 0% The weighted average grant date fair value of options granted during the nine months ended September 30, 2022 and 2021, was $3.77 per share and $1.34 per share, respectively. Prior to the Company’s IPO, the fair value of the Company’s common stock underlying the stock options was historically determined by the Board with assistance from management and, occasionally with input from an independent third-party valuation firm. For the year ended December 31, 2020, management engaged an independent third-party valuation firm to provide an estimate of the fair value of the Company’s common stock, which was utilized as an input to the Company’s Black-Scholes option pricing model for stock options awarded during the three months ended March 31, 2021. The December 31, 2020 fair value of common stock was determined considering a number of objective and subjective factors, including valuations of comparable companies, sales of convertible preferred stock, operating and financial performance, the lack of liquidity of the Company’s common stock and the general and industry specific economic outlook. The fair value of the Company’s common stock as of June 30, 2021 was estimated based upon the per share offering price of the Company’s common stock to the public in its IPO which closed on July 6, 2021. The June 30, 2021 fair value for the Company’s common stock was utilized as an input for options granted by the Company to its Board on June 30, 2021, which was immediately prior to the IPO. As of June 30, 2021 and December 31, 2020, management estimated the fair value of a share of common stock to be $16.00 and $0.83, respectively. Stock options granted after December 31, 2017 vest monthly over a range of 12 to 36 months or vest monthly over a total of 48 months following a one-year ten-year three ten-year became publicly traded in July 2021 and lacks company-specific historical and implied volatility information. Therefore, it estimates its expected stock volatility based on the historical volatility of a publicly traded set of peer companies. Due to the lack of historical exercise history, the expected term of the Company’s stock options has been determined using the “simplified” method for awards. The risk-free interest rate is determined by reference to the U.S. Treasury yield curve in effect at the time of grant of the award for time periods approximately equal to the expected term of the award. Expected dividend yield is zero based on the fact that the Company has never paid cash dividends and does not expect to pay any cash dividends in the foreseeable future. The following table reflects summarized stock option activity: Stock Options Weighted Average Weighted Average Aggregate Intrinsic Outstanding at December 31, 2021 3,835,618 $ 2.51 Granted 1,932,050 $ 5.00 Exercised (31,848 ) $ 0.86 Forfeited (79,872 ) $ 6.35 Outstanding at September 30, 2022 5,655,948 $ 3.31 8.3 $ 39,818 Vested and exercisable at September 30, 2022 2,084,736 $ 1.75 7.1 $ 17,772 As of September 30, 2022, total unrecognized compensation costs related to unvested stock option awards granted was approximately $9.4 million, which the Company expects to recognize over a weighted-average period of approximately 2.8 years. The Company recorded stock-based compensation expense related to stock options in the following expense categories of its condensed statements of operations for the periods shown (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2022 2021 2022 2021 General and administrative $ 563 $ 254 $ 1,525 $ 412 Research and development 277 50 648 145 Total stock-based compensation $ 840 $ 304 $ 2,173 $ 557 Employee Stock Purchase Plan The 2021 Employee Stock Purchase Plan (the “ESPP”), which permits employees to purchase shares of the Company’s common stock, became effective on June 30, 2021. A total of 375,000 shares of the Company’s common stock were initially reserved for sale under the ESPP. The number of shares of the Company’s common stock reserved for issuance will automatically increase on January 1 of each calendar year, beginning on January 1, 2022 and through January 1, 2031, by the lesser of (1) 1% of the total number of shares of the Company’s common stock outstanding on the last day of the fiscal year before the date of the automatic increase, and (2) 800,000 shares; provided that before the date of any such increase, the Board may determine that such increase will be less than the amount set forth in clauses (1) and (2). On January 1, 2022, the Board increased the number of shares of common stock reserved for issuance under the ESPP by 404,732 shares. As of September 30, 2022, there are 779,732 shares authorized for issuance under the ESPP and there have been no purchases of shares under the ESPP.

Leases

Leases	9 Months Ended
Leases	Sep. 30, 2022
Leases [Abstract]
Leases	NOTE 8. LEASES The Company has been subleasing space in Indiana since March 1, 2020. The Company executed a new sublease for this space that was effective on February 1, 2021 and expires on August 30, 2023. The sublease does not provide the Company with any renewal options. The Company allows others to sublease a portion of the space from the Company for less than a one-year On September 28, 2022, the Company entered into a lease for office space in Charlottesville, Virginia with a lease term of fifteen months beginning October 1, 2022. There is no automatic renewal, but any holdover tenancy shall be on a month-to-month basis thereafter. The following table summarizes quantitative information about the Company’s operating leases for the period indicated (in thousands): Three Months Ended Nine Months Ended Operating leases Operating lease cost $ 38 $ 114 Less: sublease income (12 ) (44 ) Operating lease expense 26 70 Short-term lease rent expense 1 11 Total rent expense $ 27 $ 81 Supplemental information related to the Indiana lease was as follows (dollar amounts in thousands): Nine Months Ended Operating cash flows from operating leases $ 114 Right-of-use assets obtained in exchange for operating lease liabilities $ 233 Weighted-average remaining lease term – operating leases (in years) 0.9 Weighted-average discount rate – operating leases 10.0 % As of September 30, 2022, the present value of maturities of the Company’s operating lease liabilities were as follows (in thousands): Remaining period ended December 31, 2022 $ 39 Year ended December 31, 2023 102 Total 141 Less: present value discount (8 ) Operating lease liabilities $ 133 The Company recognizes sublease income in other income (expense) on its condensed statements of operations and comprehensive loss. The Company expects to recognize approximately $3,000 in sublease income for the remainder of 2022. Prior to the adoption of ASC 842, and for the three and nine months ended September 30, 2021, the Company recognized rent expense on a straight-line basis over the lease period and recorded deferred rent expense for rent expense incurred but not yet paid. During the three and nine months ended September 30, 2021, the Company recognized total rent expense of approximately $40,000 and $107,000, respectively, and recognized sublease income of approximately $19,000 and $47,000, respectively. Disclosures related to periods prior to adoption of ASC 842 included approximate future minimum rental payments due under the Company’s leases as of December 31, 2021 as follows (in thousands): Year ended December 31, 2022 $ 153 Year ended December 31, 2023 102 Total $ 255

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
Commitments and Contingencies	Sep. 30, 2022
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	NOTE 9. COMMITMENTS AND CONTINGENCIES The Company is not a party to any material legal proceedings and is not aware of any pending or threatened claims. From time to time, the Company may be subject to various legal proceedings and claims that arise in the ordinary course of its business activities.

Net Loss Per Share

Net Loss Per Share	9 Months Ended
Net Loss Per Share	Sep. 30, 2022
Earnings Per Share [Abstract]
Net Loss Per Share	NOTE 10. NET LOSS PER SHARE The Company computes net two-class respectively.

Basis of Presentation, Summary

Basis of Presentation, Summary of Significant Accounting Policies and Recent Accounting Pronouncements (Policies)	9 Months Ended
	Sep. 30, 2022
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed financial statements have been prepared in accordance with Generally Accepted Accounting Principles in the United States of America (“U.S. GAAP”) for interim financial information, the instructions to Form 10-Q S-X. A description of the Company’s significant accounting policies is included in the Company’s Annual Report. Other than as described below, there have been no material changes in the Company’s significant accounting policies to those previously disclosed in the Company’s Annual Report.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the unaudited condensed financial statements, as well as the reported amounts of expenses during the reporting periods. These estimates and assumptions are based on the Company’s historical experience, and on various other factors that management believes are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities and the recording of expenses that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions. To the extent there are material differences between the estimates and actual results, the Company’s future results of operations will be affected.
Reclassifications	Reclassifications Certain prior year amounts have been reclassified for consistency with the current period presentation. Interest income and interest expense are combined into one line item and presented net in the condensed statements of operations and comprehensive loss, whereas these line items were previously presented separately. Similarly, in the condensed statements of cash flows, amortization of premiums and accretion of discounts on marketable securities are now presented net, but previously had been presented on separate rows as amortization of premiums and non-cash
Leases	Leases The Company accounts for its leases under Accounting Standards Codification (“ASC”) 842, Leases right-of-use right-of-use right-of-use right-of-use ASC 842 provides practical expedients for an entity’s ongoing accounting. In calculating right-of-use non-lease right-of-use
Recently Adopted Accounting Pronouncements	Recently Adopted Accounting Pronouncements ASC 842 requires lessees to recognize the liabilities related to all leases, including operating leases, with a term greater than 12 months on the balance sheet and also requires lessees and lessors to disclose key information about their leasing transactions. The Company adopted this guidance on January 1, 2022, using the modified retrospective method and the Company elected the package of practical expedients upon transition, which retained the lease classification for leases that existed prior to the adoption of this guidance. The Company recorded both a right-of-use In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes 2019-12”), 2019-12
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements In June 2016, the FASB issued ASU 2016-13, Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments available-for-sale

Marketable Securities (Tables)

Marketable Securities (Tables)	9 Months Ended
Marketable Securities (Tables)	Sep. 30, 2022
Marketable Securities [Abstract]
Summary of Marketable securities	Marketable securities consisted of the following as of September 30, 2022 and December 31, 2021 (in thousands): September 30, 2022 Amortized Gross Gross Fair Available-for-sale Corporate debt securities $ 16,531 $ — $ (369 ) $ 16,162 Asset-backed securities 3,008 — (120 ) 2,888 U.S. treasury securities 24,080 — (476 ) 23,604 Total available-for-sale 43,619 — (965 ) 42,654 Total available-for-sale $ 43,619 $ — $ (965 ) $ 42,654 December 31, 2021 Amortized Gross Gross Fair Value Available-for-sale Commercial paper $ 47,939 $ — $ — $ 47,939 Corporate debt securities 7,992 — (11 ) 7,981 Asset-backed securities 16,177 — (22 ) 16,155 Total available-for-sale 72,108 — (33 ) 72,075 Available-for-sale Corporate debt securities 16,816 — (103 ) 16,713 Asset-backed securities 3,013 — (25 ) 2,988 U.S. treasury securities 11,988 — (70 ) 11,918 Total available-for-sale 31,817 — (198 ) 31,619 Total available-for-sale $ 103,925 $ — $ (231 ) $ 103,694 As of September 30, 2022, the Company’s available-for-sale were available-for-sale that were available-for-sale

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
Fair Value Measurements (Tables)	Sep. 30, 2022
Fair Value Disclosures [Abstract]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	The Company’s financial assets and liabilities subject to fair value measurement on a recurring basis and the level of inputs used for such measurements were as follows (in thousands): Fair value measurements at reporting date using Quoted Prices in Significant Other Significant Fair Value at Assets included in: Cash and cash equivalents Money market securities $ 156,540 $ — $ — $ 156,540 Marketable securities Corporate debt securities — 16,162 — 16,162 Asset-backed securities — 2,888 — 2,888 U.S. treasury securities — 23,604 — 23,604 Total fair value $ 156,540 $ 42,654 $ — $ 199,194 Fair value measurements at reporting date using Quoted Prices in Significant Other Significant Unobservable Fair Value at Assets included in: Cash and cash equivalents Money market securities $ 121,162 $ — $ — $ 121,162 Marketable securities Commercial paper — 47,939 — 47,939 Corporate debt securities — 24,694 — 24,694 Asset-backed securities — 19,143 — 19,143 U.S. treasury securities — 11,918 — 11,918 Total fair value $ 121,162 $ 103,694 $ — $ 224,856

Supplemental Financial Inform_2

Supplemental Financial Information (Tables)	9 Months Ended
Supplemental Financial Information (Tables)	Sep. 30, 2022
Supplemental Financial Information [Abstract]
Schedule of Prepaid Expenses and Other Current Assets	Prepaid expenses and other current assets consisted of the following (in thousands): September 30, 2022 December 31, 2021 Prepaid insurance $ 1,666 $ 1,514 Prepaid raw materials 201 83 Research and development service agreements 172 2,591 Dues and subscriptions 121 96 Other 206 140 Total prepaid expenses and other current assets $ 2,366 $ 4,424
Schedule of Accrued Expenses and Other Current Liabilities	Accrued expenses and other current liabilities consisted of the following (in thousands): September 30, 2022 December 31, 2021 Research and development $ 2,837 $ 2,623 Compensat ion 1,455 1,102 Legal 67 130 Other 37 204 Total accrued expenses and other current liabilities $ 4,396 $ 4,059

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	9 Months Ended
Stock-Based Compensation (Tables)	Sep. 30, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Summary of Assumptions Used for Valuation of Fair Value of Stock Options	The Black-Scholes option-pricing model was used to estimate the fair value of stock options granted during the nine months ended September 30, 2022 and 2021 with the following weighted average assumptions: Nine Months Ended September 30, 2022 2021 Risk-free interest rate 1.71% - 4.17% 0.4% - 1.1% Expected term (in years) 5.8 - 6.1 5.3 - 6.1 Expected volatility 90% 90% Expected dividend yield 0% 0%
Summary of Stock Option Activity	The following table reflects summarized stock option activity: Stock Options Weighted Average Weighted Average Aggregate Intrinsic Outstanding at December 31, 2021 3,835,618 $ 2.51 Granted 1,932,050 $ 5.00 Exercised (31,848 ) $ 0.86 Forfeited (79,872 ) $ 6.35 Outstanding at September 30, 2022 5,655,948 $ 3.31 8.3 $ 39,818 Vested and exercisable at September 30, 2022 2,084,736 $ 1.75 7.1 $ 17,772
Summary of Share-Based Compensation Expense Related to Stock Options	The Company recorded stock-based compensation expense related to stock options in the following expense categories of its condensed statements of operations for the periods shown (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2022 2021 2022 2021 General and administrative $ 563 $ 254 $ 1,525 $ 412 Research and development 277 50 648 145 Total stock-based compensation $ 840 $ 304 $ 2,173 $ 557

Leases (Tables)

Leases (Tables)	9 Months Ended
Leases (Tables)	Sep. 30, 2022
Leases [Abstract]
Summary of Lease, Cost	The following table summarizes quantitative information about the Company’s operating leases for the period indicated (in thousands): Three Months Ended Nine Months Ended Operating leases Operating lease cost $ 38 $ 114 Less: sublease income (12 ) (44 ) Operating lease expense 26 70 Short-term lease rent expense 1 11 Total rent expense $ 27 $ 81
Schedule Of Supplemental Information Related To Lease	Supplemental information related to the Indiana lease was as follows (dollar amounts in thousands): Nine Months Ended Operating cash flows from operating leases $ 114 Right-of-use assets obtained in exchange for operating lease liabilities $ 233 Weighted-average remaining lease term – operating leases (in years) 0.9 Weighted-average discount rate – operating leases 10.0 %
Summary of Lessee, Operating Lease, Liability, Maturity	As of September 30, 2022, the present value of maturities of the Company’s operating lease liabilities were as follows (in thousands): Remaining period ended December 31, 2022 $ 39 Year ended December 31, 2023 102 Total 141 Less: present value discount (8 ) Operating lease liabilities $ 133
Schedule of Future Minimum Rental Payments for Operating Leases	Disclosures related to periods prior to adoption of ASC 842 included approximate future minimum rental payments due under the Company’s leases as of December 31, 2021 as follows (in thousands): Year ended December 31, 2022 $ 153 Year ended December 31, 2023 102 Total $ 255

Description of Organization a_2

Description of Organization and Business Operations - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	Jul. 08, 2021	Jul. 06, 2021	Jun. 23, 2021	Sep. 30, 2022	Dec. 31, 2021
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Stockholders' equity, reverse stock split			1-for-1.49
Accumulated deficit				$ (157,561)	$ (127,571)
Working capital				$ 195,900	$ 193,500
Total number of outstanding stock increased		39,911,517
Common Stock Warrants [Member] \| Common Stock [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Number of securities called by warrants or rights		178,847
Series A Convertible Preferred Stock [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Conversion of stock, shares converted		477,297
Series A-1 Convertible Preferred Stock [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Conversion of stock, shares converted		7,985,305
Series B Convertible Preferred Stock [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Conversion of stock, shares converted		19,770,070
IPO [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Sale of stock, number of shares issued in transaction		9,999,999
Underwriting shares	1,499,999
Sale of stock, price per share		$ 16
Sale of stock, consideration received on transaction		$ 168,600
underwriting discounts and commissions and other offering expenses		$ 15,400

Basis of Presentation, Summar_2

Basis of Presentation, Summary of Significant Accounting Policies and Recent Accounting Pronouncements - Additional Information (Detail) - USD ($) $ in Thousands	Sep. 30, 2022	Jan. 01, 2022	Dec. 31, 2021
Right-of-use asset	$ 133	$ 200
Lease liability	$ 133	$ 200

Marketable Securities - Additio

Marketable Securities - Additional Information (Details) - Marketable Debt Securities [Member] - USD ($) $ in Thousands		3 Months Ended	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2022	Sep. 30, 2022
Marketable Securities [Line Items]
Available-for-sale securities classified as short-term maturity	one year or less
Other than temporary impairment losses, investments portion in other comprehensive loss net of tax available-for sale securities		$ 0	$ 0

Marketable Securities - Summary

Marketable Securities - Summary of Marketable securities (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2022	Dec. 31, 2021
Marketable Debt Securities Short Term [Member]
Marketable Securities [Line Items]
Amortized cost, Short term	$ 43,619	$ 72,108
Gross Unrealized Loss	(965)	(33)
Fair value, Short Term	42,654	72,075
Marketable Debt Securities Long Term [Member]
Marketable Securities [Line Items]
Gross Unrealized Loss		(198)
Amortized cost, Long term		31,817
Fair value, Long Term		31,619
Marketable Debt Securities [Member]
Marketable Securities [Line Items]
Gross Unrealized Loss	(965)	(231)
Amortized Cost, Total	43,619	103,925
Fair value, Total	42,654	103,694
Commercial Paper [Member] \| Marketable Debt Securities Short Term [Member]
Marketable Securities [Line Items]
Amortized cost, Short term		47,939
Fair value, Short Term		47,939
Corporate Debt Securities [Member] \| Marketable Debt Securities Short Term [Member]
Marketable Securities [Line Items]
Amortized cost, Short term	16,531	7,992
Gross Unrealized Loss	(369)	(11)
Fair value, Short Term	16,162	7,981
Corporate Debt Securities [Member] \| Marketable Debt Securities Long Term [Member]
Marketable Securities [Line Items]
Gross Unrealized Loss		(103)
Amortized cost, Long term		16,816
Fair value, Long Term		16,713
Asset-backed Securities [Member] \| Marketable Debt Securities Short Term [Member]
Marketable Securities [Line Items]
Amortized cost, Short term	3,008	16,177
Gross Unrealized Loss	(120)	(22)
Fair value, Short Term	2,888	16,155
Asset-backed Securities [Member] \| Marketable Debt Securities Long Term [Member]
Marketable Securities [Line Items]
Gross Unrealized Loss		(25)
Amortized cost, Long term		3,013
Fair value, Long Term		2,988
US Treasury Securities [Member] \| Marketable Debt Securities Short Term [Member]
Marketable Securities [Line Items]
Amortized cost, Short term	24,080
Gross Unrealized Loss	(476)
Fair value, Short Term	$ 23,604
US Treasury Securities [Member] \| Marketable Debt Securities Long Term [Member]
Marketable Securities [Line Items]
Gross Unrealized Loss		(70)
Amortized cost, Long term		11,988
Fair value, Long Term		$ 11,918

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis (Detail) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Marketable securities
Total fair value	$ 199,194	$ 224,856
Fair Value, Inputs, Level 1 [Member]
Marketable securities
Total fair value	156,540	121,162
Fair Value, Inputs, Level 2 [Member]
Marketable securities
Total fair value	42,654	103,694
Fair Value, Inputs, Level 3 [Member]
Marketable securities
Total fair value	0	0
Money Market Securities [Member]
Cash and cash equivalents
Cash and Cash Equivalents, Fair Value Disclosure	156,540	121,162
Money Market Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents
Cash and Cash Equivalents, Fair Value Disclosure	156,540	121,162
Money Market Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents
Cash and Cash Equivalents, Fair Value Disclosure	0	0
Money Market Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents
Cash and Cash Equivalents, Fair Value Disclosure	0	0
Commercial Paper [Member]
Marketable securities
Investments, Fair Value Disclosure		47,939
Commercial Paper [Member] \| Fair Value, Inputs, Level 2 [Member]
Marketable securities
Investments, Fair Value Disclosure		47,939
Corporate Debt Securities [Member]
Marketable securities
Investments, Fair Value Disclosure	16,162	24,694
Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Marketable securities
Investments, Fair Value Disclosure	0
Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Marketable securities
Investments, Fair Value Disclosure	16,162	24,694
Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Marketable securities
Investments, Fair Value Disclosure	0
Asset-backed Securities [Member]
Marketable securities
Investments, Fair Value Disclosure	2,888	19,143
Asset-backed Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Marketable securities
Investments, Fair Value Disclosure	0
Asset-backed Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Marketable securities
Investments, Fair Value Disclosure	2,888	19,143
Asset-backed Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Marketable securities
Investments, Fair Value Disclosure	0
US Treasury Securities [Member]
Marketable securities
Investments, Fair Value Disclosure	23,604	11,918
US Treasury Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Marketable securities
Investments, Fair Value Disclosure	0
US Treasury Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Marketable securities
Investments, Fair Value Disclosure	23,604	$ 11,918
US Treasury Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Marketable securities
Investments, Fair Value Disclosure	$ 0

Supplemental Financial Inform_3

Supplemental Financial Information - Schedule of Prepaid Expenses and Other Current Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Disclosure Of Prepaid Expenses And Other Current Assets [Line Items]
Prepaid insurance	$ 1,666	$ 1,514
Prepaid raw materials	201	83
Research and development service agreements	172	2,591
Dues and subscriptions	121	96
Other	206	140
Total prepaid expenses and other current assets	$ 2,366	$ 4,424

Supplemental Financial Inform_4

Supplemental Financial Information - Schedule of Accrued Expenses and Other Current Liabilities (Detail) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Disclosure of Accrued Expenses and Other Current Liabilities [Line Items]
Research and development	$ 2,837	$ 2,623
Compensation and other employee liabilities	1,455	1,102
Legal	67	130
Other	37	204
Total accrued expenses and other current liabilities	$ 4,396	$ 4,059

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	9 Months Ended
	Sep. 30, 2022	Jul. 01, 2022	Dec. 31, 2021
Class of Stock [Line Items]
Common stock shares authorized	300,000,000		300,000,000
Common stock par or stated value per share	$ 0.0001		$ 0.0001
Common stock shares voting rights	one
Preferred stock, shares authorized	10,000,000		10,000,000
Total shares authorized	310,000,000
Preferred stock, par or stated value per share	$ 0.0001		$ 0.0001
Aggregate public offering price to offer and sell securities as per registration statement		$ 200
Sales Agreement [Member] \| At the market offering program [Member] \| Sales Agent [Member]
Class of Stock [Line Items]
Commission rate equal to the percentage of gross proceeds from sale of shares of common stock		3%
Aggregate offering price to issue and sell shares of common stock		$ 50

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Jan. 01, 2022	Dec. 31, 2021	Jun. 30, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of a share of common stock					$ 16	$ 0.83
Share based compensation by share based payment arrangement vesting period	48 months
Period of service minimum needed for vesting of stock options	1 year
Share based compensation by share based payment arrangement contractual term	10 years
Share based compensation by share based payment arrangement unrecognized compensation costs non vested options	$ 9.4
Share based compensation by share based payment arrangement unrecognized compensation costs weighted aveage period of recognition	2 years 9 months 18 days
Weighted average grant date fair value of options granted	$ 3.77	$ 1.34
Common stock shares authorized	300,000,000			300,000,000
Stock Options Granted Before December 31, 2017 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation by share based payment arrangement contractual term	10 years
2013 Amended And Restated Stock Performance Plan [Member] \| Stock Options Granted Before December 31, 2017 [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation by share based payment arrangement vesting period	3 months
2013 Amended And Restated Stock Performance Plan [Member] \| Stock Options Granted Before December 31, 2017 [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation by share based payment arrangement vesting period	24 months
2021 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future grant	4,030,960				7,698,282
Share based compensation arrangement by share based payment award Cumulative annual increase in common stock shares reserved for issuance, percentage					5%
Share based compensation arrangement by share based payment award number of shares authorized	9,721,945
2021 Equity Incentive Plan [Member] \| New Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future grant					3,550,000
2021 Equity Incentive Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum threshold common stock issuable on exercise of incentive stock options					12,000,000
Common stock, capital shares reserved for future issuance			2,023,663
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, capital shares reserved for future issuance			404,732
Share based compensation arrangement by share based payment award Cumulative annual increase in shares reserved for issuance, percentage					1%
Share based compensation arrangement by share based payment award shares of common stock outstanding maximum cumulative annual increase					800,000
Stock issued during period shares employee stock purchase plans	0
Common stock shares authorized	779,732
Employee Stock Purchase Plan [Member] \| Employee Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, capital shares reserved for future issuance					375,000
Two Thousand And Thirteen Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future grant					667,104
2013 and 2021 Equity Incentive Plan [Member] \| Stock Options Granted After December 31, 2017 [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation by share based payment arrangement vesting period	12 months
2013 and 2021 Equity Incentive Plan [Member] \| Stock Options Granted After December 31, 2017 [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation by share based payment arrangement vesting period	36 months

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Assumptions Used for Valuation of Fair Value of Stock (Detail) - Black-Scholes Option-Pricing Model [Member]	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Expected volatility	90%	90%
Expected dividend yield	0%	0%
Minimum [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Risk-free interest rate, minimum	1.71%	0.40%
Expected term in years	5 years 9 months 18 days	5 years 3 months 18 days
Maximum [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Risk-free interest rate, maximum	4.17%	1.10%
Expected term in years	6 years 1 month 6 days	6 years 1 month 6 days

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of Stock Option Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning balance, Stock Options	3,835,618
Stock options granted, Stock Options	1,932,050
Stock options exercised, Stock Options	(31,848)
Stock options forfeited, Stock Options	(79,872)
Ending balance, Stock Options	5,655,948
Vested and exercisable, Stock Options	2,084,736
Beginning balance, Weighted Average Exercise Price	$ 2.51
Options granted, Weighted Average Exercise Price	5
Options Exercised, Weighted Average Exercise Price	0.86
Options Forfeited, Weighted Average Exercise Price	6.35
Ending balance, Weighted Average Exercise Price	3.31
Vested and exercisable, Weighted Average Exercise Price	$ 1.75
Weighted Average Remaining Contractual Life (in years)	8 years 3 months 18 days
Vested and exercisable, Weighted Average Remaining Contractual Life (in years)	7 years 1 month 6 days
Ending balance, Aggregate Intrinsic Value	$ 39,818
Vested and exercisable, Aggregate Intrinsic Value	$ 17,772

Stock-Based Compensation - Su_3

Stock-Based Compensation - Summary of Share-Based Compensation Expense Related to Stock Options (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based compensation expense	$ 840	$ 304	$ 2,173	$ 557
General and Administrative [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based compensation expense	563	254	1,525	412
Research and Development [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based compensation expense	$ 277	$ 50	$ 648	$ 145

Leases - Summary of Lease, Cost

Leases - Summary of Lease, Cost (Detail) - USD ($)	3 Months Ended		9 Months Ended
Leases - Summary of Lease, Cost (Detail) - USD ($)	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Operating leases
Operating lease cost	$ 38,000		$ 114,000
Less: sublease income	(12,000)	$ (19,000)	(44,000)	$ (47,000)
Operating lease expense	26,000		70,000
Short-term lease rent expense	1,000		11,000
Total rent expense	$ 27,000	$ 40,000	$ 81,000	$ 107,000

Leases - Schedule Of Supplement

Leases - Schedule Of Supplemental Information Related To Lease (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Leases [Abstract]
Operating cash flows from operating leases	$ 114
Right-of-use assets obtained in exchange for operating lease liabilities	$ 233
Weighted-average remaining lease term – operating leases	10 months 24 days
Weighted-average discount rate – operating leases	10%

Leases - Summary of Lessee, Op

Leases - Summary of Lessee, Operating Lease, Liability, Maturity (Detail) - USD ($) $ in Thousands	Sep. 30, 2022	Jan. 01, 2022
Leases [Abstract]
Remaining Period Ended December 31, 2022	$ 39
Year Ended December 31, 2023	102
Total	141
Less: present value discount	(8)
Operating lease liabilities	$ 133	$ 200

Leases - Schedule of Future Min

Leases - Schedule of Future Minimum Rental Payments for Operating Leases (Detail) $ in Thousands	Dec. 31, 2021 USD ($)
Leases [Abstract]
Year ended December 31, 2022	$ 153
Year ended December 31, 2023	102
Total	$ 255

Lease - Additional Information

Lease - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
Lease - Additional Information (Detail) - USD ($)	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Leases [Abstract]
Sublease income for the remainder of 2022	$ 3,000		$ 3,000
Sublease income	12,000	$ 19,000	44,000	$ 47,000
Rent expense	$ 27,000	$ 40,000	$ 81,000	$ 107,000
Lease Term			15 months

Net Loss Per Share - Summary of

Net Loss Per Share - Summary of Dilutive Securities Not Included in the Diluted Net Loss Per Common Share (Detail) - shares	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Exercise of Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Conversion of stock, shares converted	5,655,948	3,662,365