Aligos Therapeutics (ALGS) 10-K 12 Mar 24 2023 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Mar. 08, 2024	Jun. 30, 2023
Document Information [Line Items]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2023
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Entity Registrant Name	Aligos Therapeutics, Inc.
Entity Central Index Key	0001799448
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Interactive Data Current	Yes
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Well-known Seasoned Issuer	No
Entity Public Float			$ 20.2
ICFR Auditor Attestation Flag	false
Document Financial Statement Error Correction [Flag]	false
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, par value, $0.0001 per share
Trading Symbol	ALGS
Security Exchange Name	NASDAQ
Entity File Number	001-39617
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	82-4724808
Entity Address, Address Line One	One Corporate Drive
Entity Address, Address Line Two	2nd Floor
Entity Address, City or Town	South San Francisco
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94080
City Area Code	800
Local Phone Number	466-6059
Document Annual Report	true
Document Transition Report	false
Auditor Firm ID	42
Auditor Name	Ernst & Young LLP
Auditor Location	San Mateo, California
Documents Incorporated by Reference	DOCUMENTS INCORPORATED BY REFERENCE Portions of the Registrant’s Definitive Proxy Statement relating to the 2024 Annual Meeting of Stockholders, which will be filed with the Securities and Exchange Commission within 120 days after the end of the Registrant’s fiscal year ended December 31, 2023 , are incorporated by reference into Part III of this Report.
Voting Common Stock [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		72,576,183
Non-voting Common Stock [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		3,092,338

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 135,704	$ 81,347
Restricted cash	70	115
Short-term investments		44,480
Other current assets	5,310	7,603
Total current assets	141,084	133,545
Operating lease right-of-use assets	6,559	7,698
Property and equipment, net	3,259	4,816
Other assets	625	634
Total assets	151,527	146,693
Current liabilities:
Accounts payable	2,517	4,737
Accrued liabilities	16,842	16,039
Operating lease liabilities, current	3,229	3,035
Finance lease liabilities, current	10	108
Deferred revenue from customers, current	1,224	467
Deferred revenue from collaborations, current	84	8,743
Total current liabilities	23,906	33,129
Operating lease liabilities, net of current portion	7,668	9,201
Finance lease liabilities, net of current portion	231	230
Deferred revenue from customers, net of current portion		233
Warrant liability	27,596
Long term liability	46
Total liabilities	59,447	42,793
Commitments and contingencies (Note 14)
Stockholders’ equity:
Preferred Stock, $0.0001 par value; 10,000,000 shares authorized as of December 31, 2023 and December 31, 2022, respectively; no shares issued and outstanding as of December 31, 2023 and December 31, 2022, respectively.
Common stock, $0.0001 par value; 320,000,000 shares authorized as of December 31, 2023 and December 31, 2022, respectively; 75,096,906 and 42,922,980 shares issued and outstanding as of December 31, 2023 and December 31, 2022, respectively.	7	4
Additional paid-in capital	578,325	502,613
Accumulated deficit	(486,797)	(399,118)
Accumulated other comprehensive income	545	401
Total stockholders’ equity	92,080	103,900
Total liabilities and stockholders' equity	$ 151,527	$ 146,693

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Preferred Stock, Par Value	$ 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 Stock, Shares Authorized	320,000,000	320,000,000
Common Stock, Shares, Issued	75,096,906	42,922,980
Common Stock, Shares, Outstanding	75,096,906	42,922,980

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Income Statement [Abstract]
Revenue from collaborations	$ 9,338	$ 13,907
Revenue from customers	6,191
Operating expenses:
Research and development	73,040	85,077
General and administrative	30,616	26,410
Total operating expenses	103,656	111,487
Loss from operations	(88,127)	(97,580)
Interest and other income, net	1,243	1,640
Loss before income tax expense	(86,884)	(95,940)
Income tax expense	(795)	(106)
Net loss	(87,679)	(96,046)
Other comprehensive income (loss):
Unrealized gain (loss) on available-for-sale securities	96	(57)
Gains on pension plans	48	6
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent, Total	144	(51)
Comprehensive loss	$ (87,535)	$ (96,097)
Net loss per share, basic	$ (1.36)	$ (2.25)
Net loss per share, diluted	$ (1.36)	$ (2.25)
Weighted average shares of common stock, basic	64,260,588	42,695,227
Weighted average shares of common stock, diluted	64,260,588	42,695,227

Consolidated Statements of Chan

Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)
Beginning balance at Dec. 31, 2021	$ 184,731	$ 4	$ 487,347	$ (303,072)	$ 452
Beginning balance, Shares at Dec. 31, 2021		42,690,229
Issuance of common stock upon exercise of stock options	20		20
Issuance of common stock upon exercise of stock options, shares		12,896
Issuance of common stock related to ESPP purchase	205		205
Issuance of common stock related to ESPP purchase, shares		219,855
Stock-based compensation expense related to employee stock awards	13,540		13,540
Stock-based compensation expense related to employee stock purchases	1,292		1,292
Vesting of early exercised common stock options	209		209
Other comprehensive income (loss)	(51)				(51)
Net loss	(96,046)			(96,046)
Ending balance at Dec. 31, 2022	103,900	$ 4	502,613	(399,118)	401
Ending balance, Shares at Dec. 31, 2022		42,922,980
Issuance of common stock upon exercise of stock options	23		23
Issuance of common stock upon exercise of stock options, shares		17,109
Issuance of common stock related to ESPP purchase	551		551
Issuance of common stock related to ESPP purchase, shares		727,551
Issuance of common stock in connection with PIPE offering, net of offering costs	18,644	$ 3	18,641
Issuance of common stock in connection with PIPE offering, net of offering costs,shares		31,429,266
Issuance of pre-funded warrants in connection with PIPE offering, net of offering costs	48,079		48,079
Costs related to the PIPE offering	(4,300)		(4,300)
Stock-based compensation expense related to employee stock awards	11,799		11,799
Stock-based compensation expense related to employee stock purchases	853		853
Vesting of early exercised common stock options	66		66
Other comprehensive income (loss)	144				144
Net loss	(87,679)			(87,679)
Ending balance at Dec. 31, 2023	$ 92,080	$ 7	$ 578,325	$ (486,797)	$ 545
Ending balance, Shares at Dec. 31, 2023		75,096,906

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Cash flows from operating activities:
Net loss	$ (87,679,000)	$ (96,046,000)
Adjustments to reconcile net loss to net cash used in operating activities:
Accretion of discount on investments	(424,000)	(159,000)
Amortization of right of use assets	1,510,000	1,369,000
Impairment of right of use assets	724,000	0
Change in fair value of warrant liability	2,169,000
Loss on disposal of assets	17,000
Depreciation expense	1,559,000	2,306,000
Stock-based compensation including ESPP	12,652,000	14,693,000
Changes in operating assets and liabilities:
Other assets	2,297,000	5,594,000
Right of use assets		(278,000)
Accounts payable	(2,219,000)	1,722,000
Accrued liabilities	918,000	(9,140,000)
Operating lease liabilities	(2,432,000)	(1,819,000)
Other liabilities	46,000	(133,000)
Deferred revenue from collaborations	(8,659,000)	2,502,000
Deferred revenue from customers	524,000
Net cash and cash equivalents used in operating activities	(78,997,000)	(79,389,000)
Cash flows from investing activities:
Maturities of short-term investments	45,011,000	78,915,000
Purchases of short-term investments	(11,000)	(104,265,000)
Purchases of property and equipment	(19,000)	(943,000)
Net cash and cash equivalents provided by (used in) investing activities	44,981,000	(26,293,000)
Cash flows from financing activities:
Proceeds from issuance of common stock in connection with PIPE Offering, net of costs	17,443,000
Proceeds from issuance of pre-funded warrants in connection with PIPE Offering, net of costs	44,980,000
Proceeds from issuance of common warrants in connection with PIPE Offering, net of costs	25,427,000
Payments on finance lease	(96,000)	(61,000)
Proceeds from the ESPP purchase	551,000	205,000
Net cash and cash equivalents provided by financing activities	88,328,000	164,000
Net increase (decrease) in cash, cash equivalents, and restricted cash	54,312,000	(105,518,000)
Cash, cash equivalents, and restricted cash, beginning of period	81,462,000	186,980,000
Cash, cash equivalents, and restricted cash, end of period	135,774,000	81,462,000
Reconciliation to amounts on the Consolidated Balance Sheets:
Cash and cash equivalents	135,704,000	81,347,000
Restricted cash	70,000	115,000
Cash, cash equivalents, and restricted cash, end of period	135,774,000	81,462,000
Supplemental disclosures of noncash financing and investing activities:
Mark to market adjustment for available-for-sale investments	96,000	(57,000)
Receviable due from arrangement		700,000
Acquisition of right-of-use asset through operating lease obligation	1,094,000
Vesting of early exercised options	66,000	209,000
Change in pension obligation	48,000	6,000
Employee Stock
Cash flows from financing activities:
Proceeds from the exercise of common stock option	$ 23,000	$ 20,000

Organization

Organization	12 Months Ended
	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization	1. Organization Description of business Aligos Therapeutics, Inc. (Aligos-US) was incorporated in the state of Delaware on February 5, 2018 (inception). On September 10, 2018, the Company formed Aligos Belgium BVBA (the Subsidiary or Aligos-Belgium). On March 30, 2020, the Company formed as a wholly owned subsidiary, Aligos Australia Pty LTD (Aligos-Australia), a proprietary limited company. On May 18, 2021, the Company formed as a wholly owned subsidiary, Aligos Therapeutics (Shanghai) Co. Ltd. (Aligos-Shanghai) and together with Aligos-US, Aligos-Belgium, and Aligos-Australia being the Company or Aligos. Aligos is a clinical-stage biopharmaceutical company focused on developing novel therapeutics to address unmet medical needs in liver diseases and viral infections, including in the areas of metabolic dysfunction associated steatohepatitis (MASH), chronic hepatitis B (CHB), and coronavirus (e.g., SARS-CoV-2 and related infections). The Company is devoting substantially all of its efforts to the research and development of its drug candidates. The Company has not generated any product revenue to date. The Company is also subject to a number of risks similar to other companies in the biotechnology industry, including the uncertainty of success of its preclinical studies and clinical trials, regulatory approval of drug candidates, uncertainty of market acceptance of products, competition from substitute products and larger companies, the need to obtain additional financing, compliance with government regulations, protection of proprietary technology, dependence on third-parties, product liability, and dependence on key individuals. Liquidity The Company has incurred losses and negative cash flows from operations since its inception. As of December 31, 2023 and 2022, the Company had an accumulated deficit of approximately $ 486.8 million and $ 399.1 million , respectively. Management expects to continue to incur additional substantial losses in the foreseeable future as a result of expanded research and development activities. As of December 31, 2023, the Company has cash, cash equivalent and investments of approximately $ 135.7 million , which is available to fund future operations. The Company expects to continue to spend substantial amounts to continue the nonclinical and clinical development of its current and future programs. If the Company is able to gain marketing approval for drug candidates that are being developed, it will require significant additional amounts of cash in order to launch and commercialize such drug candidates. In addition, other unanticipated costs may arise. Because the design and outcome of the Company’s planned and anticipated clinical trials is highly uncertain, the Company cannot reasonably estimate the actual amounts necessary to successfully complete the development and commercialization of any drug candidate the Company may develop. The Company expects to finance its cash needs through a combination of public or private equity offerings, debt financings, collaborations, strategic alliances, licensing arrangements and other marketing or distribution arrangements. Based on the Company’s research and development plans, it is expected that the Company’s existing cash, cash equivalents and investments, will enable the Company to fund its operations for at least 12 months following the date the consolidated financial statements are issued. However, the Company’s operating plan may change as a result of many factors currently unknown, and the Company may need to seek additional funds sooner than planned. Moreover, it is particularly difficult to estimate with certainty the Company’s future expenses given the dynamic nature of its business, and the macro-economic environment generally. The Company’s ability to raise additional funds will depend on financial, economic and other factors, many of which are beyond its control. If additional funds are not available to the Company when needed, on terms that are acceptable to the Company, or at all, the Company may be required to: delay, limit, reduce or terminate nonclinical studies, clinical trials or other research and development activities or eliminate one or more of its development programs altogether; or delay, limit, reduce or terminate its efforts to establish manufacturing and sales and marketing capabilities or other activities that may be necessary to commercialize any future approved products, or reduce the Company’s flexibility in developing or maintaining its sales and marketing strategy.

Summary of significant accounti

Summary of significant accounting policies	12 Months Ended
	Dec. 31, 2023
Accounting Policies [Abstract]
Summary of significant accounting policies	2. Summary of significant accounting policies The accompanying consolidated financial statements have been prepared on a basis that contemplates the continuity of operations, realization of assets and the satisfaction of liabilities and commitments in the normal course of business. Risks and uncertainties The Company is subject to risks common to companies in the biotechnology industry including, but not limited to, new technological innovations, protection of proprietary technology, dependence on key personnel, compliance with government regulations and the need to obtain additional financing. As a result, the Company is unable to predict the timing or amount of increased expenses or when or if the Company will be able to achieve or maintain profitability. Drug candidates currently under development will require significant additional research and development efforts, including extensive nonclinical and clinical testing and regulatory approval. Moreover, it is particularly difficult to estimate with certainty the Company’s future expenses given the dynamic nature of its business, and the macro-economic environment generally. Basis of presentation The accompanying consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (U.S. GAAP) and include all adjustments necessary for the fair presentation of the Company’s financial position for the periods presented. Any reference in these notes to applicable accounting guidance is meant to refer to the authoritative U.S. GAAP included in the Accounting Standards Codification (ASC), and Accounting Standards Update (ASU) issued by the Financial Accounting Standards Board (the FASB). Principles of consolidation The accompanying consolidated financial statements include Aligos-US and its wholly owned subsidiaries Aligos-Belgium, Aligos-Australia and Aligos-Shanghai. All intercompany balances and transactions have been eliminated. Use of estimates The preparation of the consolidated financial statements in conformity with U.S. GAAP generally requires management to make certain estimates and assumptions that affect the reported amounts in the consolidated financial statements and accompanying notes. The Company regularly evaluates estimates and assumptions related to assets and liabilities, at the dates of the consolidated financial statements and the reported amounts of expenses during the reporting period. Areas where management uses subjective judgments include, but are not limited to, right-of-use assets, lease obligations, impairment of long-lived assets, stock-based compensation, accrued research and development costs, revenue from collaborations, revenue from contracts with customers, deferred revenue, common stock warrants liability, income taxes and pension liabilities in the accompanying consolidated financial statements. Management bases its estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ materially from these estimates under different assumptions or conditions. Foreign currency The Company’s foreign subsidiaries use the U.S. dollar as their functional currency, and they initially measure the foreign currency denominated assets and liabilities at the transaction date. Monetary assets and liabilities are then re-measured at exchange rates in effect at the end of each period, and non-monetary assets and liabilities are converted at historical rates. A re-measurement loss was recognized during the year ended December 31, 2023 of $ 45.7 thousand , and a re-measurement loss was recognized during the year ended December 31, 2022 of $ 42.0 thousand , and are reflected within interest and other income, net on the Consolidated Statements of Operations and Comprehensive Loss. Segment information The Company has determined that the Chief Executive Officer is its Chief Operating Decision Maker. The Company’s Chief Executive Officer reviews financial information presented on a consolidated basis for the purposes of assessing the performance and making decisions on how to allocate resources. Accordingly, the Company has determined that it operates in a single reportable segment. No product revenue has been generated since inception. The Company has $ 2.9 million and $ 0.3 million of fixed assets in Aligos-US and Aligos-Belgium, respectively, as of December 31, 2023 and $ 4.1 million and $ 0.7 million of fixed assets in Aligos-US and Aligos‑Belgium, respectively as of December 31, 2022 . Cash equivalents The Company considers all highly liquid investments purchased with original maturities of 90 days or less at acquisition to be cash equivalents. Restricted cash As of December 31, 2023 and 2022, the restricted cash balance was $ 0.1 million and $ 0.1 million , respectively, and was used primarily to secure letters of credit in relation to the Company’s operating leases and deposits on rental assets (Note 6), as well as employee withholdings for the employee stock purchase plan . Investments The Company generally invests its excess cash in money market funds and investment grade short-to-intermediate-term fixed income securities. Such investments are included in cash, cash equivalents, short-term and long-term investments on the Consolidated Balance Sheets. The Company determines the appropriate classification of short-term and long-term securities at the time of purchase and re-evaluates such designation as of each balance sheet date. Securities are classified as held-to-maturity when the Company has the positive intent and ability to hold the securities to maturity, otherwise securities are classified as available-for sale. Held-to-maturity securities are carried at amortized cost. Available-for-sale debt securities are measured and reported at fair value using quoted prices in active markets for similar securities. Unrealized gains and losses on available-for-sale securities are reported as a separate component of stockholders’ equity. Premiums or discounts from par value are amortized to investment income over the life of the underlying investment. The cost of securities sold is determined on a specific identification basis, and realized gains and losses are included in interest and other income (expense), net within the Consolidated Statements of Operations and Comprehensive Loss. For both held-to-maturity and available-for-sale investments, the Company periodically reviews each individual security position that has an unrealized loss, or impairment, to determine if that impairment is other-than-temporary. If the Company believes an impairment of a security position is other than temporary, based on available quantitative and qualitative information as of the report date, the loss will be recognized as other income (expense), net, in the Company’s Consolidated Statements of Operations and Comprehensive Loss and a new cost basis in the investment is established. No impairment charges were recorded during the years ended December 31, 2023 and 2022. As of December 31, 2023 there were no investments on the Consolidated Balance Sheets. As of December 31, 2022 , investments consisted of Certificates of Deposit and U.S. Treasury securities, with original maturities of up to 1.50 years. Concentrations of credit risk and significant suppliers The Company has no significant off-balance sheet risk, such as foreign exchange contracts, option contracts, or other foreign hedging arrangements. Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash, restricted cash and investments. Periodically, the Company maintains deposits in accredited financial institutions in excess of federally insured limits. The Company deposits its cash in financial institutions that it believes have high credit quality and has not experienced any losses on such accounts and does not believe it is exposed to any unusual credit risk beyond the normal credit risk associated with commercial banking relationships. The Company generally invests its excess capital in money market funds, U.S. treasury bonds, U.S. treasury bills and certificates of deposit that are subject to minimal credit and market risks. The Company is dependent on various third parties to manufacture compounds for the Company to conduct research and studies for its programs. These programs would be adversely delayed by a significant interruption in the supply of active pharmaceutical ingredients. Accounting for Government Grants In 2022, the Company was awarded a grant of $ 1.1 million by the National Institute of Health (NIH) for research to target coronaviruses. The grant is for multiple years with the amount updated after each year of progress through 2025, subject to the annual reapplication and approval by the NIH. In 2023, the approved grant awarded was an additional $ 1.4 million. In 2023, the Company was awarded a contract of $ 8.5 million by the National Institute of Allergies and Infectious Diseases (NIAID) for research to target coronaviruses. This contract is for 2 years. U.S. GAAP does not contain authoritative accounting standards for grants or contracts provided by governmental entities to a for-profit entity. Absent authoritative accounting standards, interpretative guidance issued and commonly applied by financial statement preparers allows for the selection of accounting policies amongst acceptable alternatives. The Company determined it most appropriate to account for grants by analogy to International Accounting Standards 20 (“IAS 20”), Accounting for Government Grants and Disclosure of Government Assistance. Under this model, reimbursements the Company receives from the U.S. government for qualifying expenditures under the NIH grant will be recognized in earnings as a reduction to research and development expense when there is reasonable assurance that the Company will receive the grant. IAS 20 does not define “reasonable assurance”; however, the Company analogized this to “probable” as defined in FASB ASC 450-20-20 under U.S. GAAP, which is the definition the Company has applied. The grants and contracts will be recognized in earnings as a reduction of the related research and development (R&D) expenses. During the year ended December 31, 2023 , $ 1.6 million was recognized as a reduction to R&D expenses. There was no ne recognized in the year ended December 2022. Common warrants liability The Company accounts for certain warrants as liabilities at fair value and adjusts the instruments to fair value at each reporting period. The Company determined that its outstanding warrants are freestanding derivative instruments. The warrants are subject to remeasurement at each balance sheet date until exercised, and any change in fair value is recognized as a component of interest and other income, net in the Consolidated Statements of Operations and Comprehensive Loss. The fair value of the warrants issued by the Company has been estimated and is revalued at the end of each reporting period using a probability weighted Black-Scholes option pricing model. Leases The Company determines at the inception of the lease if an arrangement is a lease. Operating leases are included in operating lease right-of-use (ROU) assets and operating lease liabilities in the Consolidated Balance Sheets. Finance leases are included in property and equipment and finance lease liabilities in the Consolidated Balance Sheets. ROU assets represent the right to use an underlying asset for the lease term and lease liabilities represent the obligation to make lease payments arising from the lease. Operating lease ROU assets and liabilities are recognized at the lease commencement date based on the present value of lease payments over the lease term. When the Company’s leases do not provide an implicit rate, an incremental borrowing rate is used based on the information available at the commencement dates in determining the present value of lease payments. The Company uses the implicit rate when readily determinable. The operating lease ROU assets also include any lease payments made and excludes lease incentives when paid by the Company or on the Company’s behalf. The Company’s lease terms may include the period covered by options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Lease expense for operating leases is recognized on a straight-line basis over the lease term. The Company has lease agreements with lease and non-lease components. The Company elected to not separate lease and non-lease components for all of its building leases. For vehicle leases, lease and non-lease components are accounted for separately. The Company also made an accounting policy election to recognize lease expense for leases with a term of 12 months or less on a straight-line basis over the lease term and not recognize ROU assets or lease liabilities for such leases. Impairment of Right of Use Assets In accordance with ASC 360, Property, Plant and Equipment, management reviews the Company’s right of use assets for impairment annually or whenever events or changes in circumstances indicate that the carrying amount of an asset may not be fully recoverable. Events relating to recoverability may include significant unfavorable changes in business conditions, recurring losses, or a forecasted inability to achieve break-even operating results over an extended period. The Company determines the extent to which an asset may be impaired based upon its expectation of the asset’s future usability, as well as on a reasonable assurance that the future cash flows associated with the asset will be in excess of its carrying amount. If the total of the expected undiscounted future cash flows is less than the carrying amount of the asset, a loss is recognized for the difference between fair value and the carrying value of the asset. During the year ended December 31, 2023 , the Company vacated certain leased office space and as a result, the Company recorded an impairment charge against right of use assets of $ 0.7 million, recorded in the Consolidated Statements of Operations and Comprehensive Loss as general and administrative (G&A) expenses. No impairments were recorded in the year ended December 31, 2022 . Property and equipment Property and equipment is stated at cost less accumulated depreciation, and is depreciated using the straight-line method over the estimated useful life of the asset, which are as follows: Lab equipment 3 years Computer equipment 3 years Furniture and office equipment 3 - 8 years Vehicles 4 years Leasehold improvements Shorter of the useful life or Expenditures for repairs and maintenance of assets are charged to expense as incurred. Upon retirement or sale, the cost and related accumulated depreciation of assets disposed of are removed from the accounts and any resulting gain or loss is included in loss from operations. Impairment of long-lived assets The Company regularly reviews the carrying amount of its property, equipment and intangible assets to determine whether indicators of impairment may exist which warrant adjustments to carrying values or estimated useful lives. If indications of impairment exist, projected future undiscounted cash flows associated with the asset are compared to the carrying amount to determine whether the asset’s value is recoverable. If the carrying value of the asset exceeds such projected undiscounted cash flows, the asset will be written down to its estimated fair value. No impairment charges were recorded during the years ended December 31, 2023 or 2022 . Research and development expenses Research and development costs are expensed as incurred. Research and development expenses consist of costs incurred in performing research and development activities, including salaries, stock-based compensation and benefits, facilities costs, depreciation, and third-party license fees. Non-refundable prepayments for goods or services that will be used or rendered for future research and development activities are deferred and capitalized. In-process research and development (IPR&D) expense represents the costs to acquire technologies to be used in research and development that have not reached technological feasibility or have no alternative future uses and thus are expensed as incurred. IPR&D expense also includes upfront license fees and milestones paid to collaborators for technologies with no alternative use. Collaborative arrangements The Company enters into collaboration arrangements with pharmaceutical and other partners, under which the Company may grant licenses to its collaboration partners to research and develop potential drug candidates. Consideration under these contracts may include an upfront payment, development, regulatory, sales and other milestone payments. Contractual payments received for research and development activities performed are recognized on a gross basis in revenue from collaboration arrangements. The Company may also perform research and development activities under the collaboration agreements where the Company may be granted licenses from its collaboration partners. Contractual payments to the other party in collaboration agreements and costs incurred by the Company are recognized on a gross basis in research and development expenses. Royalties and license payments are recorded as due. When the Company enters into collaboration arrangements, the Company assesses whether the arrangement falls within the scope of ASC 808, Collaborative Arrangements (ASC 808) based on whether the arrangement involves joint operating activities and whether both parties would be active participants and would be exposed to significant risks and rewards of the arrangement. To the extent that the arrangement falls within the scope of ASC 808, the Company assesses whether the payments between the parties fall within the scope of other accounting literature such as ASC 606, Revenue from Contracts with Customers (ASC 606). The upfront payments received during the years ended December 31, 2023 and 2022 were recorded on the Consolidated Balance Sheets as Deferred Revenue from Collaborations. Revenue from contracts with customers The Company enters into revenue arrangements with certain partners. Consideration under these contracts may include an upfront payment, development, regulatory, sales and other milestone payments. Contractual payments received for research and development activities performed are recognized on a gross basis in Revenue from Customers. The Company may also perform research and development activities under the revenue agreements where the Company may be granted licenses from its partners. Contractual payments to the other party in revenue agreements and costs incurred by the Company are recognized on a gross basis in research and development expenses. Royalties and license payments are recorded as due. When the Company enters into revenue arrangements, the Company assesses whether the arrangement first falls within the scope of ASC 808, Collaborative Arrangements (ASC 808) based on whether the arrangement involves joint operating activities and whether both parties would be active participants and would be exposed to significant risks and rewards of the arrangement. If the arrangement does not fall into this literature, the Company then looks to ASC 606, Revenue from Contracts with Customers (ASC 606) to see whether the partner is considered a customer. The upfront payments received during the years ended December 31, 2023 and 2022 were recorded on the Consolidated Balance Sheets as Deferred Revenue from Customers. Fair value measurements Certain assets and liabilities of the Company are carried at fair value under U.S. GAAP. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable: Level 1 —Quoted prices in active markets for identical assets or liabilities. Level 2 —Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data. Level 3 —Unobservable inputs that are supported by little or no market activity that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques. Stock-based compensation The Company’s stock-based awards consist of restricted stock awards and stock options. For stock-based awards issued to employees and nonemployees, the Company measures the estimated fair value of the stock-based awards on the date of grant and recognizes compensation expense for those awards over the requisite service period, which is generally the vesting period of the respective awards. The Company records expense for awards with service-based vesting using the straight-line method. The Company accounts for forfeitures as they occur. The Company classifies stock-based compensation expense in its Consolidated Statements of Operations and Comprehensive Loss in the same manner in which the award recipient’s cash compensation costs are classified. The fair value of each restricted stock award is determined based on the number of shares granted and the value of the Company’s common stock on the date of grant. The fair value of each stock option award is estimated on the date of grant using the Black-Scholes option pricing model. The Black-Scholes option-pricing model requires the use of a number of assumptions including the fair value of the common stock, expected volatility, risk-free interest rate, expected dividends, and expected term of the option. The Company determined the expected stock volatility using a weighted-average of the historical volatility of a group of guideline companies that issued options with substantially similar terms, and expects to continue to do so until such time as the Company has adequate historical data regarding the volatility of its own traded stock price. The expected term of the Company’s stock options has been determined utilizing the simplified method for awards that qualify as “plain-vanilla” options. 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. The Company has no t paid, and does not anticipate paying, cash dividends on its common stock; therefore, the expected dividend yield is assumed to be zero . The fair value of the Company’s 2020 Employee Stock Purchase Plan (the ESPP) is determined on the date the offering period begins using a Black-Scholes option-pricing model and similar assumptions for stock options as described above. See Note 9 for the assumptions used by the Company in determining the grant date fair value of stock-based awards granted, as well as a summary of the stock-based award activity under the Company’s stock-based compensation plan for years ended December 31, 2023 and 2022 . Income taxes Deferred tax assets and liabilities are determined on the basis of the differences between the consolidated financial statements and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Changes in deferred tax assets and liabilities are recorded in the provision for income taxes. The Company assesses the likelihood that its deferred tax assets will be recovered from future taxable income and, to the extent it believes, based upon the weight of available evidence, that it is more likely than not that all or a portion of the deferred tax assets will not be realized, a valuation allowance is established. The Company accounts for uncertain tax positions recognized in the consolidated financial statements by prescribing a more-likely-than-not threshold for financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. The provision for income taxes includes the effects of any resulting tax reserves, or unrecognized tax benefits, that are considered appropriate as well as the related interest and penalties. Net loss per share Basic net loss per share attributable to common stockholders is calculated by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period, without consideration for potentially dilutive securities. The weighted-average number of shares of common stock outstanding includes the shares subject to the pre-funded warrants as per ASC 260, shares issuable for little or no cash consideration upon the satisfaction of certain conditions, shall be considered outstanding common shares. Diluted net loss per share attributable to common stockholders is computed by dividing the net loss attributable to common stockholders by the weighted-average number of common stock and potentially dilutive securities outstanding for the period. For purposes of the diluted net loss per share calculation, stock options, common stock subject to repurchase related to early exercise of stock options, unvested restricted stock subject to repurchase, common stock warrants and convertible notes are considered to be potentially dilutive securities. Accordingly, in periods in which the Company reports a net loss, diluted net loss per share is the same as basic net loss per share, since dilutive common shares are not assumed to have been issued if their effect is anti-dilutive. Benefit plans The Company has established a defined contribution savings plan for its employees in Aligos-US under Section 401(k) of the Internal Revenue Code, and a defined benefits plan for its employees in Aligos-Belgium. The Company uses the standard method for the recognition of the actuarial results as described in ASC 715. This means application of a 10 % corridor and amortization over the expected average remaining working lives of the employees. The plan contains benefits to the plan participant on the normal plan retirement date and benefits to the partner after death of the plan participant. This plan is recognized under ASC 715. Recently issued accounting standards In June 2016, the FASB issued ASU No. 2016-13. Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments (ASU 2016-13), which requires that financial assets measured at amortized cost be presented at the net amount expected to be collected. Currently, U.S. GAAP delays recognition of the full amount of credit losses until the loss is probable of occurring. Under this ASU, the income statement will reflect an entity’s current estimate of all expected credit losses. The measurement of expected credit losses will be based upon historical experience, current conditions, and reasonable and supportable forecasts that affect the collectability of the reported amount. In November 2018, the FASB issued ASU No. 2018-19, Codification Improvements to Topic 326, Financial Instruments—Credit Losses (ASU 2018-19), which clarifies that receivables from operating leases are accounted for using the lease guidance and not as financial instruments. In April 2019, the FASB issued ASU No. 2019-04, Codification Improvements to Topic 326, Financial Instruments—Credit Losses (ASU 2019-04), which clarifies the new expected credit loss methodology for loans, receivables and other financial assets, including recoveries and accrued interest on receivables. In November 2019, the FASB issued ASU No. 2019-11, Codification Improvements to Topic 326 , Financial Instruments—Credit Losses (ASU 2019-11), which clarifies guidance around how to report expected recoveries. The standard is effective for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years. Early adoption is permitted. The Company adopted this standard in fiscal year 2023 and there was not a material impact on its consolidated financial statements. In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes (ASU 2019-12). The guidance removes specific exceptions to the general principles in ASC 740, improves application of income tax-related guidance and reduces complexity related to the accounting for income taxes. The standard is effective for fiscal years beginning after December 15, 2020. Early adoption is permitted. The Company adopted this standard in fiscal year 2021 and there is not a material impact on its consolidated financial statements. From time to time, new accounting pronouncements are issued by FASB that the Company adopts as of the specified effective date. The Company qualifies as an “emerging growth company” as defined in the Jumpstart Our Business Startups Act of 2012 and has the option to not “opt out” of the extended transition related to complying with new or revised accounting standards. This means that when a standard is issued or revised and it has different application dates for public and nonpublic companies, the Company has the option to adopt the new or revised standard at the time nonpublic companies adopt the new or revised standard and can do so until such time that the Company either (i) irrevocably elects to “opt out” of such extended transition period or (ii) no longer qualifies as an emerging growth company.

Property and equipment

Property and equipment	12 Months Ended
	Dec. 31, 2023
Property, Plant and Equipment [Abstract]
Property and equipment	3. Property and equipment The components of property and equipment were as follows as of December 31, 2023 and 2022: December 31, December 31, Leasehold improvements $ 6,101 $ 6,087 Lab equipment 5,830 6,179 Computer equipment 1,051 1,052 Furniture and office equipment 732 739 Vehicles 296 305 Asset under construction 4 22 Total, at cost 14,014 14,384 Accumulated depreciation ( 10,755 ) ( 9,568 ) Total, net $ 3,259 $ 4,816 During the years ended December 31, 2023 and 2022, depreciation expense was $ 1.6 million and $ 2.3 million , respectively. Finance leases for vehicles and lab equipment are also included in property and equipment on the Consolidated Balance Sheets (Note 6).

Investments

Investments	12 Months Ended
	Dec. 31, 2023
Debt Securities, Available-for-Sale and Held-to-Maturity, after Allowance for Credit Loss [Abstract]
Investments	4. Investments As of December 31, 2022, amortized cost, gross unrealized gains and losses, and estimated fair values of total fixed-maturity securities were as follows: December 31, 2022 Gross Gross Amortized Unrealized Unrealized Estimated Cost Gain Loss Fair Value Available-for-sale securities: U.S. Treasury bonds $ 44,576 $ - $ ( 96 ) $ 44,480 The Company had no available for sale securities as of December 31, 2023. Changes in fair value are related to changes in market interest rates. The Company expects to collect all contractual principal and interest payments. The Company recorded interest income of $ 4.3 million and $ 1.5 million , respectively, during the years ended December 31, 2023 and 2022 , as a component of interest and other income, net on the Company’s Consolidated Statement of Operations and Comprehensive Loss.

Accrued liabilities

Accrued liabilities	12 Months Ended
	Dec. 31, 2023
Payables and Accruals [Abstract]
Accrued liabilities	5. Accrued liabilities Accrued liabilities consisted of the following as of December 31: December 31, December 31, 2023 2022 Accrued compensation $ 6,673 $ 6,297 Accrued payables 7,144 8,203 Liability for early exercised stock options - 66 Other 3,025 1,473 Total $ 16,842 $ 16,039 As of December 31, 2023 , there remains a $ 0.3 million accrual, included within Accrued Compensation for employee severance, none of which is expected to remain by the end of 2024.

Leases

Leases	12 Months Ended
	Dec. 31, 2023
Leases [Abstract]
Leases	6. Leases The Company has operating and finance leases for corporate offices, research and development facilities, and certain vehicles and lab equipment. These leases have remaining lease terms of three to five years , some of which include options to extend the leases for five to eight years . The Company has determined that it is not reasonably certain to exercise the options under any leases. The lease of research and development facilities includes costs for utilities and common area maintenance which have been included in the calculation of lease payments. Differences between lease payments as measured at lease inception and variations in monthly payments will be recognized as operating expenses in the period in which the obligation is incurred. The Company entered into a 5-year lease in the fourth quarter of 2021. The lease is for approximately 12,000 square feet of office space in South San Francisco, with a renewal option for an additional 5-years , which we are not certain to renew at this time. The rental payments under the lease agreement are approximately $ 2.7 million over the lease term. During the year ended December 31, 2023 , the Company vacated certain leased office space and as a result, the Company took an impairment charge against right of use assets of $ 0.7 million, recorded in the Consolidated Statements of Operations and Comprehensive Loss. No impairments were made in the year ended December 31, 2022. Leases with an initial term of 12 months or less are not recorded on the balance sheet, and the Company recognizes lease expense for these leases on a straight-line basis over the lease terms. Leases with terms greater than 12 months are included in operating lease ROU assets and operating lease liabilities in the Company’s Consolidated Balance Sheets as of December 31, 2023 and 2022. Lease expense is recognized on a straight-line basis over the lease term. Maturities of lease liabilities as of December 31, 2023, were as follows: Operating Finance Year ending December 31: 2024 $ 3,562 $ 63 2025 3,680 65 2026 3,801 44 2027 1,443 - 2028 161 - Thereafter - - 12,647 172 Less: imputed interest ( 1,750 ) 69 Present value of lease liabilities 10,897 241 Less: current portion ( 3,229 ) ( 10 ) Lease liabilities, net of current portion $ 7,668 $ 231 The components of lease expense were as follows for the years ended December 31, 2023 and 2022: 2023 2022 Operating lease cost $ 2,321 $ 2,504 Finance lease cost: Amortization of right-of-use assets $ 84 $ 108 Interest on lease liabilities 11 13 Total finance lease cost $ 95 $ 121 The Company made payments of $ 3.6 million and $ 3.4 million during the years ended December 31, 2023 and 2022, respectively, which are included as cash flow from operations on the Consolidated Statements of Cash Flows. As of December 31, 2023 and 2022, $ 0.7 million and $ 0.7 million of finance lease ROU assets, respectively, were presented as part of property and equipment on the Consolidated Balance Sheets with accumulated amortization of $ 0.4 million and $ 0.3 million , respectively. Additional information related to the Company’s leases was as follows as of December 31: December 31, December 31, 2023 2022 Operating Lease: Weighted-average remaining lease term (years) 3.38 4.21 Weighted-average discount rate 7.94 % 9.04 % Finance Lease: Weighted-average remaining lease term (years) 2.67 3.26 Weighted-average discount rate 5.57 % 5.15 %

Capital stock

Capital stock	12 Months Ended
	Dec. 31, 2023
Equity [Abstract]
Capital stock	7. Capital stock Common stock On October 20, 2020, the certificate of incorporation was amended to increase the total shares of common stock authorized for issuance to 320,000,000 and decrease the total shares of preferred stock authorized for issuance to 10,000,000 with a par value of $ 0.0001 per share. 300,000,000 shares of the common stock were designated as “Voting Common Stock” and 20,000,000 shares of the common stock were designated as “Non-Voting Common Stock”. The holders of shares of voting common stock are entitled to one vote for each share of common stock at all meetings of stockholders. Preferred stock As of December 31, 2023 and 2022 , there were 10,000,000 shares of preferred stock authorized and no preferred stock issued.

Common Warrants and Pre Funded

Common Warrants and Pre Funded Warrants	12 Months Ended
	Dec. 31, 2023
Warrants and Rights Note Disclosure [Abstract]
Common Warrants and Pre Funded Warrants	8. Common Warrants and Pre Funded Warrants In October 2023, the Company entered into the Securities Purchase Agreement with certain institutional and accredited investors, pursuant to which the Company agreed to offer, issue and sell to these investors, in a private placement, 31,429,266 shares of common stock, par value $ 0.0001 per share (the "Common Stock"), 2023 Pre-Funded Warrants to purchase an aggregate of 81,054,686 shares of Common Stock,, and Common Warrants to purchase an aggregate of 56,241,973 shares of Common Stock. Each Pre-Funded Warrant has an exercise price of $ 0.0001 per share of common stock, was immediately exercisable and is exercisable until exercised in full. Each accompanying Common Warrant has an exercise price of $ 0.7568 per share of common stock, is immediately exercisable and will expire on October 25, 2030 . The closing of the offering occurred on October 25, 2023. The Company received gross proceeds of approximately $ 92.1 million, and after deducting the placement agent fees and expenses and offering costs, net proceeds were approximately $ 86.2 million. The Company measured the fair value of the Common Stock and the Pre-Funded Warrants based on the $ 0.7568 per share purchase price stated in the Securities Purchase Agreement. The Company measured the fair value of the 2023 Common Warrants using the Black-Scholes option pricing model. The Company used the with-and-without method to allocate the net proceeds received from the sale of the Common Stock, the Pre-Funded Warrants, and the Common Warrants on the Consolidated Balance Sheets as follows: As of October 25, 2023 Common Stock $ 18,641 Pre-Funded Warrants $ 48,079 Common Warrants $ 25,427 Total $ 92,147 The following table summarizes information about shares issuable under the Pre-Funded Warrants outstanding at December 31, 2023: Pre-funded warrant shares outstanding Outstanding at January 1, 2023 - Issued 81,054,686 Outstanding at December 31, 2023 81,054,686 Exercisable at December 31, 2023 81,054,686 The following table sets forth a summary of the activities of the Company’s warrant liability, which represents a recurring measurement that is classified with Level 3 of the fair value hierarchy wherein the fair value is estimated using significant unobservable inputs: Common warrant liability Beginning liability as of January 1, 2023 - Common warrants issued 25,427 Change in fair value of liability as of December 31, 2023 2,169 Ending liability as of December 31, 2023 27,596 The fair value of the common warrants was measured using the Black Scholes option pricing model and will be remeasured each reporting period, and the change in fair value will be recorded in earnings. The assumptions that the Company used to determine the fair value at issuance and the reporting date of the common warrants granted to participants were as follows: 2023 Expected term (in years) 6.83 - 7.00 Risk-free interest rate 3.88 % - 4.98 % Dividend yield - Volatility 81.09 % - 82.80 % The following table summarizes information about shares issuable under the Common Warrants outstanding at December 31, 2023: Common warrant shares outstanding Outstanding at January 1, 2023 - Issued 56,241,973 Outstanding at December 31, 2023 56,241,973 Exercisable at December 31, 2023 56,241,973

Stock-based compensation

Stock-based compensation	12 Months Ended
	Dec. 31, 2023
Share-Based Payment Arrangement [Abstract]
Stock-based compensation	9. Stock-based compensation 2018 Equity incentive plan The Company’s 2018 Equity Incentive Plan (the 2018 Plan) allows the Company to issue restricted stock awards and restricted stock units, and to grant incentive stock options or non-qualified stock options. Incentive stock options may be granted only to the Company’s employees including officers and members of the Board who are also employees. Restricted stock awards, restricted stock units and non-qualified stock options may be granted to employees, members of the Board, outside advisors, and consultants of the Company (the Participants). The Company is authorized to issue awards for 4,913,665 shares of Common Stock under the 2018 Plan. The Company has granted awards of common stock in the form of 4,279,693 shares as of December 31, 2023 with none remaining available for future grant. Following the Company’s IPO in October 2020, all remaining shares from the 2018 Plan will be available for issuance under the 2020 Plan (as defined below). 2020 Incentive award plan The Company adopted the 2020 Incentive Award Plan (the 2020 Plan) effective October 15, 2020. The 2020 Plan provides for a variety of stock-based compensation awards, including stock options, stock appreciation rights, or SARs, restricted stock awards, restricted stock unit awards, performance bonus awards, performance stock unit awards, dividend equivalents, or other stock or cash based awards. The Company has granted 11,173,830 shares subject to awards as of December 31, 2023 with 1,992,349 remaining available for future grant. Following the effectiveness of the 2020 Plan, the Company will not make any further grants under the 2018 Plan. However, the 2018 Plan will continue to govern the terms and conditions of the outstanding awards granted under this plan. Shares of common stock subject to awards granted under the 2018 Plan that are forfeited or lapse unexercised and which following the effective date of the 2020 Plan are not issued under the 2018 Plan will be available for issuance under the 2020 Plan. 2020 Employee stock purchase plan The Company adopted the 2020 Employee Stock Purchase Plan (the 2020 ESPP) effective on October 15, 2020. The 2020 ESPP enables eligible employees of the Company to purchase shares of common stock at a discount to fair market value. The Company has initially reserved for issuance 368,901 shares of common stock pursuant to the 2020 ESPP. As of December 31, 2023, 993,016 grants of awards under this plan have been made. During the year ended December 31, 2023 and 2022, the Company's 2020 ESPP compensation expense was $ 0.9 million and $ 1.3 million , respectively. The assumptions that the Company used to determine the grant-date fair value of shares granted to participants were as follows, disclosed on a grant date basis: 2023 2022 Expected term (in years) 0.5 - 2.0 years 0.5 - 2.0 years Risk-free interest rate 2.07 % - 5.38 % 1.54 % - 4.62 % Dividend yield - - Volatility 50.36 % - 64.26 % 57.21 % - 73.67 % Weighted-average estimated fair value of purchase rights $ 0.16 - $ 2.43 $ 0.28 - $ 2.46 Stock options The exercise price for incentive stock options is at least 100 % of the fair market value on the date of grant for stockholders owning less than 10% of the voting power of all classes of stock, or at least 110 % of the fair market value for stockholders owning more than 10% of the voting power of all classes of stock. Options generally expire in 10 years and vest over periods determined by the Board, generally 48 months . Certain stock options referred to as “early exercise stock options” permit the holders to exercise the option in whole or in part prior to the full vesting of the option in exchange for unvested shares of Restricted Stock with respect to any unvested portion of the option so exercised. During the years ended December 31, 2023 and December 31, 2022, the Company’s stock option compensation expense was approximately $ 11.8 million and $ 13.5 million , respectively, and there was no recognized tax benefit in either year. As of December 31, 2023, the unamortized expense balance was $ 9.4 million , to be amortized over a weighted-average period of 1.37 years. The assumptions that the Company used to determine the grant-date fair value of stock options granted to Participants were as follows, pre sented on a weighted-average basis: 2023 2022 Expected term (in years) 6.00 5.95 Risk-free interest rate 3.83 % 2.20 % Dividend yield - - Volatility 76.65 % 80.41 % Stock option activity during the year ended December 31, 2023 and 2022 was as follows: Shares Weighted- Weighted- Aggregate Outstanding as of December 31, 2021 5,692,514 $ 12.07 8.63 $ 16,763 Granted 5,090,824 $ 2.58 Exercised ( 12,896 ) $ 1.57 19 Forfeited or Expired ( 930,315 ) $ 8.72 Outstanding as of December 31, 2022 9,840,127 $ 7.49 8.28 $ — Granted 2,251,160 $ 1.19 Exercised ( 17,109 ) $ 1.34 $ — Forfeited or Expired ( 1,697,340 ) $ 6.00 Outstanding as of December 31, 2023 10,376,838 $ 6.38 6.90 $ — Options vested and expected to vest as of December 31, 2023 10,376,838 $ 6.38 6.90 $ — Options vested and exercisable as of December 31, 2023 6,049,770 $ 8.08 5.77 $ — The weighted-average grant date fair value of stock options granted was $ 0.82 per share during the year ended December 31, 2023. The weighted-average grant date fair value of stock options granted was $ 1.80 per share during the year ended December 31, 2022. During the years ended December 31, 2023 and 2022 the Company did not issue shares for unvested stock options. As of December 31, 2022, there were 28,711 shares of Common Stock, respectively, held by employees subject to repurchase at an aggregate price of $ 0.1 million , respectively. A corresponding liability was recorded and included in accrued expenses on the Consolidated Balance Sheets as of December 31, 2022. As of December 31, 2023 , there were no shares of Common Stock held by employees subject to repurchase. Restricted stock awards The Company may grant restricted stock purchase awards to the Participants to purchase restricted stock under the Company’s Plan, which are subject to vesting conditions. The purchase prices of the restricted stock are determined by the Board. The Company has a right to repurchase the shares if the Participant’s service period is not fulfilled or upon termination of service at the original per share issuance price. The right of repurchase lapses over a service period which is typically four years with 25 % vesting on the first anniversary of the vesting commencement date and 1/48 each month thereafter. Before the adoption of the Company’s Plan, the Company granted 502,964 restricted stock awards to employees and founders. These restricted stock awards have similar characteristics to the restricted stock awards granted under the Company’s Plan, other than the right of repurchase, which typically lapses over three years with 33 % vesting on the first anniversary of the vesting commencement date and 1/36 each month thereafter. During the years ended December 31, 2023 and 2022, the Company recorded a total stock-based compensation expense of $ 31.0 thousand and $ 0.1 million , respectively, related to the restricted stock awards. As of December 31, 2023, there was $ 0.1 million unrecognized stock-based compensation costs related to outstanding unvested restricted stock awards that are expected to vest over 1.14 years. As of December 31, 2022 , there was no unrecognized stock-based compensation costs related to outstanding unvested restricted stock awards that are expected to vest. The following table summarizes the Company’s restricted common stock activity for years ended December 31, 2023 and 2022: Number Weighted- Aggregate Issued and unvested as of December 31, 2021 89,054 $ 1.30 $ 117 Restricted stock awards granted - - - Restricted stock awards vested ( 89,054 ) 1.30 ( 117 ) Issued and unvested as of December 31, 2022 - - - Restricted stock awards granted 134,120 0.84 113 Restricted stock awards vested — - - Issued and unvested as of December 31, 2023 134,120 $ 0.84 $ 113 Stock-based compensation expense was allocated as follows for the years ended December 31, 2023 and December 31, 2022: Year Ended December 31, 2023 2022 Research and development $ 6,843 $ 8,006 General and administrative 5,809 6,687 Total $ 12,652 $ 14,693

Fair value measurements

Fair value measurements	12 Months Ended
	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Fair value measurements	10. Fair value measurements The following tables present the fair value of the Company’s financial instruments that are measured or disclosed at fair value on a recurring basis: Fair Value Measurements Level 1 Level 2 Level 3 Assets: Cash equivalents $ 135,704 $ - $ - Liabilities: Warrant liability ( 27,596 ) $ 135,704 $ - $ ( 27,596 ) Fair Value Measurements Level 1 Level 2 Level 3 Assets: Cash equivalents $ 81,347 $ - $ - U.S. Treasury bonds 44,480 - - $ 125,827 $ - $ -

License and collaboration agree

License and collaboration agreements	12 Months Ended
	Dec. 31, 2023
License And Collaboration Agreements [Abstract]
License and collaboration agreements	11. License and collaboration agreements Agreements with Merck In December 2020, the Company and Merck Sharp & Dohme Corp. (Merck), a subsidiary of Merck & Co., Inc., entered into an exclusive License and Research Collaboration Agreement (Original Agreement) under which Merck and the Company agreed to apply the Company’s oligonucleotide platform technology to discover, research, optimize and develop oligonucleotides directed against a MASH target and up to one additional liver-targeted cardiometabolic and/or fibrosis target. Under the terms of the Original Agreement, the Company received an upfront payment of $ 12 million from Merck. With respect to the collaboration target, the Company is eligible to receive up to $ 458.0 million in development and commercialization milestones as well as tiered royalties on net sales of licensed products. These potential payments consist of (i) potential development milestones (such as for the first dosing of an animal specimen in a Good Laboratory Practice toxicology study, and initiation of Phase 1, 2 and 3 clinical trials), (ii) regulatory milestones (such as for marketing authorizations for a product in certain countries) and (iii) sales-based milestones. The Company is primarily responsible for designing, preparing and evaluating the oligonucleotide molecules and delivering optimized lead molecules, and Merck is responsible for subsequent research, clinical development and commercialization efforts. In January 2022, the Company and Merck entered into an amendment to the exclusive License and Research Collaboration Agreement (the First Amendment, together with the Original Agreement, the Expanded Arrangement). As a result of the First Amendment, our collaboration with Merck was expanded to include our grant of rights to Merck of an early-stage program with respect to a second undisclosed MASH target, on which the Company had previously been working independently. In addition, under this Expanded Arrangement, Merck has the ability to add an additional third target of interest in the cardiometabolic/fibrosis space to the collaboration. This right to add an additional third target expired in January 2023. Under the Expanded Arrangement, the Company received an upfront payment of $ 15 million from Merck for our grant of rights to the program directed at a second undisclosed MASH target. Moreover, the Company may receive an additional payment of $ 15 million from Merck if Merck elects to designate a third target for collaboration. With respect to the second target in the collaboration, the Company is eligible to receive up to approximately $ 460.0 million in development and commercialization milestones as well as tiered royalties on net sales. These potential payments consist of (i) potential development milestones (such as for the first dosing of an animal specimen in a Good Laboratory Practice toxicology study, and initiation of Phase 1, 2 and 3 clinical trials), (ii) regulatory milestones (such as for marketing authorizations for a product in certain countries) and (iii) sales-based milestones. In February 2023, Merck provided to the Company written notice of termination for one of the targets in the collaboration. The Company determined that the Original Agreement and First Amendment fall within the scope of ASC 808, Collaborative Arrangements (ASC 808), due to Merck and the Company being joint active participants, as well as both parties having significant risks and rewards. The Company analogized to ASC 606, Revenue from Contracts with Customers (ASC 606), for the accounting of payments including upfront payments and other milestones. Management of the Company determined that there was one performance obligation for each of the agreements given the deliverables are not distinct. The Company evaluated the performance obligation within each agreement and determined the performance obligations are satisfied over time as Merck jointly owns any collaboration intellectual property that is developed during the research term. Given the nature of the arrangements, the Company believes that the satisfaction of its performance obligations is best measured by the progress of its efforts. As such, the Company has used an input method based on costs incurred to recognize revenue associated with the upfront payments. This assessment is performed separately for each of the Original Agreement and the First Amendment, and the Company recognizes revenue over time based on the costs incurred. The effect of any updates to the estimated overall costs are recorded as a change in estimate. In addition, variable consideration (e.g., milestone payments) were evaluated based on the Company’s analysis that the possibility of achieving any of the milestone payments is remote, and therefore determined to be constrained and excluded from the transaction price. Similarly, the Company accounts for the future royalties under the sales-based royalty exception in ASC 606-10-55-65 through 55-65B therefore they are not considered in the transaction price and expected to be recognized when future sales occur since that is expected to occur after the performance obligation has been fully satisfied. Agreement with Emory University (Emory) In June 2018, the Company entered into a license agreement with Emory (the Emory License Agreement), pursuant to which Emory granted the Company a worldwide, sublicensable license under certain of its intellectual property rights to make, have made, develop, use, offer to sell, sell, import and export products containing certain compounds relating to Emory’s hepatitis B virus capsid assembly modulator technology, for all therapeutic and prophylactic uses. Such license is initially exclusive with respect to specified licensed patents owned by Emory and non-exclusive with respect to certain of Emory’s specified know-how. In June 2022, the license to such patents became non-exclusive with respect to all fields except for the treatment and prevention of HBV; however, the Company may select up to six compounds which will maintain exclusivity with respect to all therapeutic and prophylactic uses. With respect to all other compounds that are enabled by the licensed patents, those which are jointly invented by the Company and Emory or inventors in the Schinazi laboratory, or which are disclosed in a specified licensed patent, are licensed to the Company exclusively including as to Emory; whereas all other such compounds are licensed to the Company non-exclusively. Under the terms of the Emory License Agreement, the Company is obligated to use commercially reasonable efforts to bring licensed products to market in accordance with a mutually agreed upon development plan. Unless terminated earlier by either party in accordance with the provisions thereof, the Emory License Agreement shall continue until the expiration of the last–to-expire of the patents licensed to the Company thereunder. In June 2020, the Company amended the license agreement with Emory. Pursuant to the amended license agreement, Emory granted the Company additional patent rights to certain compounds targeting the treatment or prevention of HBV. As consideration for the additional rights, the Company made a one-time, non-refundable payment to Emory in the amount of $ 0.2 million, with an additional obligation to pay up to a maximum of $ 35,000 . On the same date, the Company entered into a collaboration agreement with Emory, with the initial research plan pertaining to the synthesis and evaluation of the compounds licensed through the additional patent rights granted in the amended license agreement. The research plan was set to terminate one year from the effective date of June 2020 but the Company exercised its option to extend it for a second year. In June 2022, the research plan terminated. In connection with the research plan, the Company will provide Emory funding up to $ 0.3 million per year. The Company has agreed to pay Emory up to an aggregate of $ 125.0 million upon the achievement of specified development, regulatory, and commercial milestones, and all ongoing patent costs. During the twelve months ended December 31, 2023 and 2022 , the Company had no expenses related to milestone payments. The Company also agreed to pay Emory tiered single-digit royalties on worldwide annual net sales of licensed products, on a quarterly basis and calculated on a product-by-product basis. With respect to licensed products containing any of a specified subset of the licensed compounds, such royalties range from a mid-single digit to a high-single digit percentage rate. With respect to licensed products which do not contain such compounds, the royalties span a range of percentage rates within the mid-single digits if a Phase 1 clinical trial is initiated for the product within three years of the effective date of the Emory License Agreement, and range from a low-single digit to a mid-single digit rate if a Phase 1 clinical trial is initiated more than three years after the effective date. During the twelve months ended December 31, 2023 and 2022 , the Company made no payments associated with royalties but did recognize general expenses of $ 0.4 million and $ 0.2 million, respectively. Agreement with Luxna Biotech Co., Ltd. (Luxna) On December 19, 2018, the Company entered into a license agreement with Luxna, pursuant to which Luxna granted the Company an exclusive, worldwide, sublicensable license under certain of Luxna’s intellectual property rights to research, develop make, have made and commercialize for all therapeutic and prophylactic uses, (i) products containing oligonucleotides targeting the hepatitis B virus genome, (ii) products containing certain oligonucleotides targeting up to three genes which contribute to MASH, which the Company may select at any time during the first eight years of the term, to the extent not licensed to a third party, and (iii) products containing oligonucleotides targeting up to three genes which contribute to hepatocellular carcinoma, which the Company may select at any time during the first three years of the term, which expired in December 2021. As consideration for this agreement, the Company paid an upfront license fee of $ 0.6 million. In April 2020, the Company amended the license agreement with Luxna. Pursuant to the amended license agreement, Luxna granted the Company an exclusive, worldwide license under the licensed patents to research, develop, make, have made and commercialize products containing oligonucleotides targeting three families of viruses: Orthomyxoviridae, Paramyxoviridae, and Coronaviridae (a family which includes SARS-CoV-2). As consideration for the amended license agreement, the Company paid Luxna a one-time non-refundable fee of $ 0.2 million in April 2020. The Company is obligated to make payments to Luxna, in aggregate, totaling up to but no more than $ 55.5 million upon the achievement of specified development, regulatory, and commercial milestones. During the twelve months ended December 31, 2023 and 2022 , the Company recognized no expenses related to milestone payments. The Company is also required to pay Luxna a low-single digit royalty percentage on net sale of applicable products, if any. During the twelve months ended December 31, 2023 and 2022 , the Company made no payments associated with royalties. Agreement with Katholieke Universiteit Leuven (KU Leuven) On June 25, 2020, the Company entered into a Research, Licensing and Commercialization Agreement (KU Leuven Agreement) with KU Leuven, under which the Company is collaborating with KU Leuven’s Rega Institute for Medical Research, as well as its CD3, to research and develop potential protease inhibitors for the treatment, diagnosis or prevention of coronaviruses, including of SARS-CoV-2. Unless terminated earlier by either party in accordance with provisions in the agreement, the collaboration period will terminate at the earlier of completion of all collaboration activities or 2.5 years. In connection with the KU Leuven Agreement, KU Leuven and the Company granted each other exclusive cross-licenses to use certain know-how and existing patents of the other party as well as certain joint know-how and joint patents to carry out research and development collaboration activities during the collaboration period. As of December 2022, the original collaboration period has expired. An amendment to the agreement was agreed in July 2023 to include a new collaboration plan. KU Leuven granted to the Company an exclusive (including as to KU Leuven), worldwide license under certain of KU Leuven’s know-how and existing patents, and certain joint patents and joint know-how, to manufacture and commercialize the licensed products for the treatment, diagnosis or detection of viral infections in humans. KU Leuven reserved the right to use all KU Leuven knowhow, existing KU Leuven patents, joint patents and joint know-how for academic and non-commercial research and teaching purposes. As consideration for this license, the Company is obligated to make payments to KU Leuven, in aggregate, totaling up to but no more than $ 30.0 million upon the achievement of certain commercial sales milestones. For each licensed product developed through KU Leuven and the Company’s collaborative effort, the Company is obligated to make payments to KU Leuven, in aggregate, totaling up to $ 32.0 million upon the achievement of certain development and regulatory milestones. The Company is also required to pay KU Leuven a low-to-mid-single digit royalty percentage, subject to certain adjustments, on net sales of applicable products, if any. The Company is also required to pay a share of upfront transaction consideration received to KU Leuven should the program be partnered with an external party. Unless terminated earlier by either party, the agreement shall continue until the expiration of the last to expire royalty term, which is the later of the expiration or termination of the last valid patent claim covering the manufacture, use, sale or importation of the licensed product in a particular country or 10 years after the first commercial sale of a licensed product. During the year ended December 31, 2023 , we recognized and paid $ 2.0 million related to milestone payments due to the first dosing of the first patient in a Phase 1 clinical trial. No milestone payments were made in the year ended December 31, 2022. During the twelve months ended December 31, 2023 and 2022, the Company recognized $ 9.3 million and $ 13.9 million in revenue from collaborative arrangements related to upfront payments. During the twelve months ended December 31, 2023 and 2022 , the Company recognized no revenue from collaborative arrangements related to milestone payments. The unrecognized portion of the upfront payments received during the twelve months ended December 31, 2023 and 2022 is recorded on the Consolidated Balance Sheets as “Deferred revenue from collaborations”. Changes in deferred revenue balances arose as a result of the Company recognizing the following revenue from collaborative arrangements during the periods below (in thousands): As of December 31, 2023 2022 Deferred revenue from collaborations as of January 1 $ 8,743 $ 7,641 Consideration received in the period $ 679 $ 15,009 Revenue from collaborations recognized in the period $ ( 9,338 ) $ ( 13,907 ) Deferred revenue from collaborations as of December 31 $ 84 $ 8,743

Revenue from contracts with cus

Revenue from contracts with customers	12 Months Ended
	Dec. 31, 2023
Revenue from Contract with Customer [Abstract]
Revenue from contracts with customers	12. Revenue from contracts with customers Agreement with ADCT The Company determined that the ADC Therapeutics (ADCT) agreement falls within the scope of ASC 606. The agreement did not fall under the ASC 808 guidance due to ADCT and the Company not being joint active participants, nor both parties having significant risks and rewards. Management of the Company determined that there was one performance obligation for the agreements given the deliverables are not distinct. The Company evaluated the performance obligation and determined the performance obligations are satisfied over time. Given the nature of the arrangement, the Company believes that the satisfaction of its performance obligations is best measured by the progress of its efforts. As such, the Company has used an input method based on costs incurred to recognize revenue associated with the upfront payments, and the Company recognizes revenue over time based on the costs incurred. The effect of any updates to the estimated overall costs are recorded as a change in estimate. In addition, variable consideration (e.g., milestone payments) were evaluated based on the Company’s analysis that the possibility of achieving any of the milestone payments is remote, and therefore determined to be constrained and excluded from the transaction price. Similarly, the Company accounts for the future royalties under the sales-based royalty exception in ASC 606-10-55-65 through 55-65B therefore they are not considered in the transaction price and expected to be recognized when future sales occur since that is expected to occur after the performance obligation has been fully satisfied. Agreement with Amoytop In May 2023, the Company and Amoytop Biotech Co., Ltd (Amoytop) entered into an exclusive Development Agreement and Research Collaboration Agreement with a focus on nucleic acid technology for HBV treatment, with the Company granting to Amoytop an exclusive option to enter into an exclusive license to develop and commercialize such compounds. Under the terms of the agreement, the Company received an upfront payment of $ 7.0 million, less withholding taxes of $ 1.1 million from Amoytop. With respect to the agreement, the Company will be eligible for up to $ 109.0 million in development and commercialization milestones as well as tiered royalties on net sales. These potential payments consist of (i) potential development milestones (such as for the commencement of a Good Laboratory Practice toxicology study for a collaboration compound, approval of IND by regulatory authority, initiation of Phase 2 and 3 clinical trials, and regulatory approval of a licensed product), and (ii) sales-based milestones. The Company determined that the Amoytop agreement falls within the scope of ASC 606. The agreement did not fall under the ASC 808 guidance due to Amoytop and the Company not being joint active participants, and both parties not having significant risks and rewards. Management of the Company determined that there were three performance obligations for the agreement given the deliverables are distinct. The Company evaluated the standalone selling price for each obligation based on available data for similar arrangements. The Company evaluated the performance obligations and determined the provision of R&D services for the collaboration compound performance obligation will be satisfied over time, the research license including data and know-how has been satisfied, and the provision of materials will be satisfied upon delivery. Given the nature of the arrangement, the Company believes that the satisfaction of its performance obligations is best measured by the progress of its efforts as it relates to the performance of the R&D services. As such, the Company has used an input method based on costs incurred to recognize revenue associated with the upfront payments, and the Company recognizes revenue over time based on the costs incurred. The effect of any updates to the estimated overall costs are recorded as a change in estimate. In addition, variable consideration (e.g., milestone payments) were evaluated based on the Company’s analysis that the possibility of achieving any of the milestone payments is remote, and therefore determined to be constrained and excluded from the transaction price. Similarly, the Company accounts for the future royalties under the sales-based royalty exception in ASC 606-10-55-65 through 55-65B therefore they are not considered in the transaction price and expected to be recognized when future sales occur since that is expected to occur after the performance obligation has been fully satisfied. During the twelve months ended December 31, 2023, the Company recognized $ 6.2 million in revenue from customers related to upfront payments. There was no revenue recognized from customers in the twelve months ended December 31, 2022. During the twelve months ended December 31, 2023 and 2022 , the Company recognized no revenue from customers related to milestone payments. The unrecognized portion of the upfront payments received during the twelve months ended December 31, 2023 and 2022 is recorded on the Consolidated Balance Sheets as “Deferred revenue from customers”. Changes in deferred revenue balances arose as a result of the Company recognizing the following revenue from customers during the periods below (in thousands): As of December 31, 2023 2022 Deferred revenue from customers as of January 1 $ 700 $ — Consideration received in the period $ 6,715 $ 700 Revenue from customers recognized in the period $ ( 6,191 ) $ — Deferred revenue from customers as of December 31 $ 1,224 $ 700

Income taxes

Income taxes	12 Months Ended
	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Income taxes	13. Income taxes The components of the current provision for income taxes were as follows for the years ended December 31, 2023 and 2022: 2023 2022 Current: State $ - $ - Federal - - Foreign 795 106 Total current provision for income taxes $ 795 $ 106 Deferred: State $ - $ - Federal - - Foreign - - Total deferred provision for income taxes $ - $ - The Company did no t have any deferred provision for income taxes for the years ended December 31, 2023 and 2022. A reconciliation of the expected income tax (benefit) computed using the federal statutory income tax rate to the Company’s effective income tax rate is as follows for the years ended December 31, 2023 and 2022: 2023 2022 Income tax computed at federal statutory rate 21.00 % 21.00 % State taxes, net of federal benefit 6.71 % 6.95 % R&D credit carryovers 6.35 % 1.25 % Change in valuation allowance 86.68 % - 26.32 % Stock based compensation - 2.30 % - 1.08 % Permanent differences - 0.63 % - 1.91 % Section 382 limitation - 117.98 % 0.00 % Foreign tax - 0.76 % 0.00 % Effective income tax rate - 0.93 % - 0.11 % The components of the deferred tax assets and liabilities were as follows at December 31: 2023 2022 Deferred tax assets: Net operating loss carryforward $ 3,491 $ 82,775 Operating lease liabilities 3,280 4,057 Tax credits 941 8,025 Other accruals and reserves 1,622 1,398 Stock-based compensation 2,714 2,055 Deferred revenue 24 27 Capitalized Sec 174 costs 23,962 14,138 Other 577 253 36,611 112,728 Valuation allowance ( 34,235 ) ( 109,560 ) Net deferred tax assets $ 2,376 $ 3,168 Deferred tax liabilities: Right of use assets ( 2,078 ) ( 2,803 ) Stock-based compensation - - Property and equipment ( 298 ) ( 365 ) Total deferred tax liabilities $ ( 2,376 ) $ ( 3,168 ) Total deferred income taxes $ - $ - Management believes that, based on a number of factors, including the Company’s historical operating performance and accumulated deficit, it is more likely than not that the deferred tax assets will not be utilized, such that a full valuation allowance has been recorded against the Company’s deferred tax assets. In assessing the reliability of deferred tax assets, management considers whether it is more likely than not that some portion or all of the deferred tax assets will not be realized on a jurisdiction by jurisdiction basis. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the periods in which those temporary differences become deductible. The valuation allowance decreased by $ 75.3 million during the year ended December 31, 2023, and increased by $ 25.3 million during the year ended December 31, 2022. As of December 31, 2023, the Company had $ 3.7 million of federal and $ 12.7 million of state net operating loss (NOL) carryforwards available to offset future taxable income. The Company’s federal NOL carryforwards can be carried forward indefinitely while state NOL carryforwards, if not utilized, will begin expiring in 2043 . As of December 31, 2023, the Company had research and development credit carryforwards of $ 0.2 million and $ 0.2 million available to reduce future taxable income, if any, for federal and state income tax purposes, respectively. If not utilized, the federal credit carryforwards will begin expiring in 2043 . The California credit carryforwards have no expiration date. The Company had $ 6.0 million of Australian NOL carryforwards and $ 0.7 million of Australian research and development tax credit carryforwards available. The Australian NOL and research and development tax credits have no expiration date. Under Sections 382 and 383 of the Code, and corresponding provisions of state law, if a corporation undergoes an “ownership change” (generally defined as a greater than 50 percentage point change (by value) in its equity ownership over a rolling three-year period), the Company’s ability to use its pre-change NOL carryforwards and other pre-change tax attributes to offset its post-change income may be limited. The Company performed a Code Section 382 analysis in 2023 and determined there was an ownership change that resulted in Section 382 limitations. As of the ownership change, $ 288.6 million and $ 407.1 million of federal and state net operating losses, respectively, and $ 9.7 million and $ 4.8 million of research and development credit carryforwards were written off We may experience additional ownership changes as a result of subsequent shifts in our stock ownership, some of which may be outside of our control. In the future, if we earn net taxable income, our ability to use our pre-change net operating loss carryforwards or other tax attributes to offset U.S. federal taxable income may be subject to limitations, which could potentially result in increased future tax liability to us and could adversely affect our business, results of operations, and cash flows. In addition, under current tax law, federal NOL carryforwards generated in periods after December 31, 2017, may be carried forward indefinitely but, may only be used to offset 80 % of our taxable income. The Company adopted the provisions of FASB Accounting Standards Codification (ASC) 740-10, Accounting for Uncertainty in Income Taxes , upon the date of incorporation. ASC 740-10 prescribes a comprehensive model for the recognition, measurement, presentation and disclosure in financial statements of any uncertain tax positions that have been taken or expected to be taken on a tax return. It is the Company’s policy to include penalties and interest expense related to income taxes as a component of other expense and interest expense, respectively, as necessary. During the years ended December 31, 2023 and 2022 , the Company had no t recognized any tax-related penalties or interest. No liability related to uncertain tax positions is recorded on the financial statements related to uncertain tax positions. 2023 2022 Balance, beginning of the period $ 3,100 $ 2,441 (Decrease) Increase related to prior year positions ( 3,100 ) 687 Increase (Decrease) related to current year positions 99 ( 28 ) Balance, end of the period $ 99 $ 3,100 The Company does not expect that its uncertain tax positions will materially change in the next twelve months. The reversal of the uncertain tax benefits would not impact the Company's effective tax rate as the Company continues to maintain a full valuation allowance against its deferred tax assets. The Company files income tax returns in the United States, including California and Texas, Australia, Belgium, and China. The Company is not currently under examination by income tax authorities in federal, state or other jurisdictions. All income tax returns will remain open for examination by the federal, state and foreign authorities for three or four years, from the date of utilization of any NOLs or credits. In January 2018, the FASB released guidance on the accounting for tax on the global intangible low-taxed income (GILTI) provisions of the Tax Cuts and Jobs Act of 2017. The GILTI provisions impose a tax on foreign income in excess of a deemed return on tangible assets of foreign corporations. The guidance allows companies to make an accounting policy election to either (i) account for GILTI as a component of tax expense in the period in which they are subject to the rules (the period cost method), or (ii) account for GILTI in the Company’s measurement of deferred taxes (the deferred method). After completing the analysis of the GILTI provisions, the Company elected to account for GILTI using the period cost method.

Commitments and contingencies

Commitments and contingencies	12 Months Ended
	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and contingencies	14. Commitments and contingencies From time to time, the Company may have certain contingent liabilities, including legal matters that arise in the ordinary course of its business activities. The Company accrues a liability for such matters when it is probable that future expenditures will be made and such expenditures can be reasonably estimated. Contingent liabilities requiring accrual were appropriately accrued as of December 31, 2023 and December 31, 2022. The Company enters into contracts in the normal course of business that includes arrangements with clinical research organizations, vendors for preclinical research and vendors for manufacturing. These agreements generally allow for cancellation with notice. As of December 31, 2023, the Company had no material non-cancellable purchase commitments. On March 26, 2022, the Company received notice of a complaint (the Complaint) filed by Janssen Biopharma, LLC (Janssen), which generally concerned an alleged breach by certain of our employees of their obligations to Janssen as prior employees of Janssen by purporting to assign to Aligos various inventions allegedly owned by Janssen. The Complaint was filed on March 9, 2022 in the Superior Court of the State of California, County of San Mateo, against the Company, Lawrence M. Blatt, Chairman, Chief Executive Officer and Director of the Company, and Leonid Beigelman, the former President and a former Director of the Company. The Complaint alleged breach of contract by Lawrence M. Blatt and Leonid Beigelman and tortious interference with contract by the Company and sought declaratory judgment of ownership of certain intellectual property by the Company, among other claims. The Complaint stated that Janssen was seeking injunctive relief, assignment of certain intellectual property from the Company to Janssen and monetary damages. On August 4, 2022, the Company filed counterclaims against Janssen alleging Janssen had engaged in unfair competition and promissory fraud, and on August 22, 2022, the Company filed its response to the Complaint. On October 16, 2023, the Company entered into a settlement agreement with Janssen that provided for the resolution of the action brought by Janssen alleging breach of contract by Lawrence M. Blatt, and Leonid Beigelman, and tortious interference with contract by the Company and seeking declaratory judgment of ownership of certain intellectual property by the Company, among other claims. Pursuant to the settlement agreement, Janssen agreed to dismiss the action and released the Company, Dr. Blatt and Dr. Beigelman from the claims alleged. In addition, pursuant to the Settlement Agreement, the Company agreed to dismiss the counterclaims against Janssen alleging unfair competition and promissory fraud and released Janssen from the alleged counterclaims.

Benefit plans

Benefit plans	12 Months Ended
	Dec. 31, 2023
Retirement Benefits [Abstract]
Benefit plans	15. Benefit plans Defined contribution plans The Company established a defined contribution savings plan under Section 401(k) of the Internal Revenue Code. This plan covers substantially all employees who meet minimum age and service requirements and allows participants to defer a portion of their annual compensation on a pre-tax basis. The Company made matching contributions of $ 0.8 million and $ 0.9 million to the plan during the years ended December 31, 2023 and 2022, respectively. Defined benefit plans—regular pension plan ASC Topic 715, Compensation—Retirement Benefits , requires an employer to: (a) recognize in its statement of financial position an asset for a plan’s overfunded status or a liability for a plan’s under-funded status; (b) measure a plan’s assets and its obligations that determine its funded status as of the end of the employer’s fiscal year; and (c) recognize changes in the funded status of a defined benefit post retirement plan in the year in which the changes occur. Accordingly, the Company is required to report changes in its funded status on its Consolidated Statement of Changes in Stockholders’ Equity and Consolidated Statement of Operations and Comprehensive Loss. Aligos-Belgium offers its employees a regular pension plan in the form of a defined contribution plan (the Regular Pension Plan), which contains a 1.75 % legally required minimum rate of return for the participants. The Regular Pension Plan does not meet all the requirements that are needed for recognition of the plans as a defined contribution plan. The Company therefore recognizes the Regular Pension Plan as a defined benefit plan. The Company measures the fair value of the Regular Plan assets by using Level 3 inputs, unobservable inputs that are supported by little or no market activity that are significant to determining the fair value of assets, including pricing models, discounted cash flow methodologies and similar techniques. The net periodic benefit cost of the Pension Plan was $ 0.2 million and $ 0.3 million , and is recognized in accrued liabilities on the Consolidated Balance Sheets as of December 31, 2023 and 2022, respectively. As of December 31, 2023, the projected benefit obligation was $ 1.2 million , the plan assets were $ 1.2 million and the net pension liability was $ 0.1 million . As of December 31, 2022, the projected benefit obligation was $ 1.1 million , the plan assets were $ 1.0 million , and the net pension liability was $ 0.1 million . The Company has recorded the unfunded amount as a liability in its Consolidated Balance Sheets at December 31, 2023 and 2022, under the accrued liabilities caption. The unrealized actuarial gain and loss on pension benefits, net of tax, at December 31, 2023 and 2022 was $ 40.0 thousand and $ 101.0 thousand , respectively. These amounts were reflected in other comprehensive loss under the caption gain (loss) on pension plans. The Company expects to make contributions to the Pension Plan of approximately $ 0.1 million during 2024. The Company estimates future benefit payments from 2025 to 2028 to be $ 0.3 million , and from 2029 thereafter to be $ 0.8 million . Defined benefit plans—Top Hat Plan In Aligos-Belgium, the Company established a pension bonus complementary plan (the Top Hat Plan), where the bonus payments to each participant are added to the Top Hat Plan. The annual contributions to this plan are based on performance and determined on a discretionary basis by the Company. The Top Hat Plan contains a legal yield guarantee of 1.75 %. The Top Hat Plan became effective as of January 1, 2019. In 2019, the Company accounted for the Top Hat Plan in accordance with ASC 715— Compensation—Retirement Benefits , once it became effective. The Top Hat Plan does not meet all the requirements that are needed for recognition as a defined contribution plan. The Company therefore recognizes the Top Hat Plan as a defined benefit plan. The net periodic benefit cost of the Top Hat Plan was $ 0.2 million and $ 0.2 million , and is recognized in accrued liabilities on the Consolidated Balance Sheets as of December 31, 2023 and 2022, respectively. As of December 31, 2023, the projected benefit obligation was $ 2.0 million , the plan assets were $ 1.8 million and the net pension liability was $ 0.2 million . As of December 31, 2022, the projected benefit obligation was $ 1.7 million , the plan assets were $ 1.5 million , and the net pension liability was $ 0.2 million . The Company has recorded the unfunded amount as a liability in its Consolidated Balance Sheets at December 31, 2023 and 2022, under the accrued liabilities caption. The unrealized actuarial gain and loss on pension benefits, net of tax, at December 31, 2023 and 2022 was $ 3.0 thousand and $ 60.0 thousand , respectively. These amounts were reflected in other comprehensive loss under the caption gain (loss) on pension plans. The Company expects to make contributions to the Pension Plan of approximately $ 0.2 million during 2024. The Company estimates future benefit payments from 2025 to 2028 to be $ 0.5 million , and from 2029 thereafter to be $ 1.1 million .

Net loss per share

Net loss per share	12 Months Ended
	Dec. 31, 2023
Earnings Per Share [Abstract]
Net loss per share	16. Net loss per share The following table summarizes the computation of basic and diluted net loss per share of the Company: Year Ended December 31, 2023 2022 Net loss $ ( 87,679 ) $ ( 96,046 ) Weighted average common stock outstanding, 64,260,588 42,695,227 Net loss per share - basic and diluted $ ( 1.36 ) $ ( 2.25 ) The Company’s potentially dilutive securities, which include options to purchase common stock, unvested restricted stock and warrants to purchase common stock, have been excluded from the computation of diluted net loss per share as the effect would be to reduce the net loss per share. Therefore, the weighted-average number of shares of Common Stock outstanding used to calculate both basic and diluted net loss per share is the same. The Company excluded the following potential shares of Common Stock, presented based on amounts outstanding at each period end, from the computation of diluted net loss per share for the periods indicated because including them would have had an anti-dilutive effect: Year Ended December 31, 2023 2022 Options to purchase common stock 10,376,838 9,840,127 Unvested restricted stock 134,120 - Warrants to purchase common stock 56,241,973 - 66,752,931 9,840,127

Subsequent events

Subsequent events	12 Months Ended
	Dec. 31, 2023
Subsequent Events [Abstract]
Subsequent events	17. Subsequent events Option Exchange In January 2024, the Company commenced a stock option exchange program (the "Exchange Offer") pursuant to which eligible employees were provided the opportunity to exchange eligible stock options for a number of new replacement option grants at the exchange ratio of 1 replacement option for every 1.4 eligible options tendered for those priced between $ 2.10 to $ 11.85 , and 1 replacement option for every 3.4 eligible options tendered for those priced over $ 11.86 . The Exchange Offer was concluded in February 2024. In connection with the Exchange Offer, the Company canceled 3,880,332 eligible options and granted 1,906,153 replacement options. The exchange of these options was accounted for as a modification of share-based compensation awards. Accordingly, the Company will recognize the unamortized compensation cost related to the canceled options as well as the incremental compensation cost associated with the replacement options over their one year vesting term.

Summary of significant accoun_2

Summary of significant accounting policies (Policies)	12 Months Ended
	Dec. 31, 2023
Accounting Policies [Abstract]
Risks and uncertainties	Risks and uncertainties The Company is subject to risks common to companies in the biotechnology industry including, but not limited to, new technological innovations, protection of proprietary technology, dependence on key personnel, compliance with government regulations and the need to obtain additional financing. As a result, the Company is unable to predict the timing or amount of increased expenses or when or if the Company will be able to achieve or maintain profitability. Drug candidates currently under development will require significant additional research and development efforts, including extensive nonclinical and clinical testing and regulatory approval. Moreover, it is particularly difficult to estimate with certainty the Company’s future expenses given the dynamic nature of its business, and the macro-economic environment generally.
Basis of presentation	Basis of presentation The accompanying consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (U.S. GAAP) and include all adjustments necessary for the fair presentation of the Company’s financial position for the periods presented. Any reference in these notes to applicable accounting guidance is meant to refer to the authoritative U.S. GAAP included in the Accounting Standards Codification (ASC), and Accounting Standards Update (ASU) issued by the Financial Accounting Standards Board (the FASB).
Principles of consolidation	Principles of consolidation The accompanying consolidated financial statements include Aligos-US and its wholly owned subsidiaries Aligos-Belgium, Aligos-Australia and Aligos-Shanghai. All intercompany balances and transactions have been eliminated.
Use of estimates	Use of estimates The preparation of the consolidated financial statements in conformity with U.S. GAAP generally requires management to make certain estimates and assumptions that affect the reported amounts in the consolidated financial statements and accompanying notes. The Company regularly evaluates estimates and assumptions related to assets and liabilities, at the dates of the consolidated financial statements and the reported amounts of expenses during the reporting period. Areas where management uses subjective judgments include, but are not limited to, right-of-use assets, lease obligations, impairment of long-lived assets, stock-based compensation, accrued research and development costs, revenue from collaborations, revenue from contracts with customers, deferred revenue, common stock warrants liability, income taxes and pension liabilities in the accompanying consolidated financial statements. Management bases its estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ materially from these estimates under different assumptions or conditions.
Foreign currency	Foreign currency The Company’s foreign subsidiaries use the U.S. dollar as their functional currency, and they initially measure the foreign currency denominated assets and liabilities at the transaction date. Monetary assets and liabilities are then re-measured at exchange rates in effect at the end of each period, and non-monetary assets and liabilities are converted at historical rates. A re-measurement loss was recognized during the year ended December 31, 2023 of $ 45.7 thousand , and a re-measurement loss was recognized during the year ended December 31, 2022 of $ 42.0 thousand , and are reflected within interest and other income, net on the Consolidated Statements of Operations and Comprehensive Loss.
Segment information	Segment information The Company has determined that the Chief Executive Officer is its Chief Operating Decision Maker. The Company’s Chief Executive Officer reviews financial information presented on a consolidated basis for the purposes of assessing the performance and making decisions on how to allocate resources. Accordingly, the Company has determined that it operates in a single reportable segment. No product revenue has been generated since inception. The Company has $ 2.9 million and $ 0.3 million of fixed assets in Aligos-US and Aligos-Belgium, respectively, as of December 31, 2023 and $ 4.1 million and $ 0.7 million of fixed assets in Aligos-US and Aligos‑Belgium, respectively as of December 31, 2022 .
Cash equivalents	Cash equivalents The Company considers all highly liquid investments purchased with original maturities of 90 days or less at acquisition to be cash equivalents.
Restricted cash	Restricted cash As of December 31, 2023 and 2022, the restricted cash balance was $ 0.1 million and $ 0.1 million , respectively, and was used primarily to secure letters of credit in relation to the Company’s operating leases and deposits on rental assets (Note 6), as well as employee withholdings for the employee stock purchase plan .
Investments	Investments The Company generally invests its excess cash in money market funds and investment grade short-to-intermediate-term fixed income securities. Such investments are included in cash, cash equivalents, short-term and long-term investments on the Consolidated Balance Sheets. The Company determines the appropriate classification of short-term and long-term securities at the time of purchase and re-evaluates such designation as of each balance sheet date. Securities are classified as held-to-maturity when the Company has the positive intent and ability to hold the securities to maturity, otherwise securities are classified as available-for sale. Held-to-maturity securities are carried at amortized cost. Available-for-sale debt securities are measured and reported at fair value using quoted prices in active markets for similar securities. Unrealized gains and losses on available-for-sale securities are reported as a separate component of stockholders’ equity. Premiums or discounts from par value are amortized to investment income over the life of the underlying investment. The cost of securities sold is determined on a specific identification basis, and realized gains and losses are included in interest and other income (expense), net within the Consolidated Statements of Operations and Comprehensive Loss. For both held-to-maturity and available-for-sale investments, the Company periodically reviews each individual security position that has an unrealized loss, or impairment, to determine if that impairment is other-than-temporary. If the Company believes an impairment of a security position is other than temporary, based on available quantitative and qualitative information as of the report date, the loss will be recognized as other income (expense), net, in the Company’s Consolidated Statements of Operations and Comprehensive Loss and a new cost basis in the investment is established. No impairment charges were recorded during the years ended December 31, 2023 and 2022. As of December 31, 2023 there were no investments on the Consolidated Balance Sheets. As of December 31, 2022 , investments consisted of Certificates of Deposit and U.S. Treasury securities, with original maturities of up to 1.50 years.
Concentrations of credit risk and significant suppliers	Concentrations of credit risk and significant suppliers The Company has no significant off-balance sheet risk, such as foreign exchange contracts, option contracts, or other foreign hedging arrangements. Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash, restricted cash and investments. Periodically, the Company maintains deposits in accredited financial institutions in excess of federally insured limits. The Company deposits its cash in financial institutions that it believes have high credit quality and has not experienced any losses on such accounts and does not believe it is exposed to any unusual credit risk beyond the normal credit risk associated with commercial banking relationships. The Company generally invests its excess capital in money market funds, U.S. treasury bonds, U.S. treasury bills and certificates of deposit that are subject to minimal credit and market risks. The Company is dependent on various third parties to manufacture compounds for the Company to conduct research and studies for its programs. These programs would be adversely delayed by a significant interruption in the supply of active pharmaceutical ingredients.
Accounting for Government Grants	Accounting for Government Grants In 2022, the Company was awarded a grant of $ 1.1 million by the National Institute of Health (NIH) for research to target coronaviruses. The grant is for multiple years with the amount updated after each year of progress through 2025, subject to the annual reapplication and approval by the NIH. In 2023, the approved grant awarded was an additional $ 1.4 million. In 2023, the Company was awarded a contract of $ 8.5 million by the National Institute of Allergies and Infectious Diseases (NIAID) for research to target coronaviruses. This contract is for 2 years. U.S. GAAP does not contain authoritative accounting standards for grants or contracts provided by governmental entities to a for-profit entity. Absent authoritative accounting standards, interpretative guidance issued and commonly applied by financial statement preparers allows for the selection of accounting policies amongst acceptable alternatives. The Company determined it most appropriate to account for grants by analogy to International Accounting Standards 20 (“IAS 20”), Accounting for Government Grants and Disclosure of Government Assistance. Under this model, reimbursements the Company receives from the U.S. government for qualifying expenditures under the NIH grant will be recognized in earnings as a reduction to research and development expense when there is reasonable assurance that the Company will receive the grant. IAS 20 does not define “reasonable assurance”; however, the Company analogized this to “probable” as defined in FASB ASC 450-20-20 under U.S. GAAP, which is the definition the Company has applied. The grants and contracts will be recognized in earnings as a reduction of the related research and development (R&D) expenses. During the year ended December 31, 2023 , $ 1.6 million was recognized as a reduction to R&D expenses. There was no ne recognized in the year ended December 2022.
Common warrants liability	Common warrants liability The Company accounts for certain warrants as liabilities at fair value and adjusts the instruments to fair value at each reporting period. The Company determined that its outstanding warrants are freestanding derivative instruments. The warrants are subject to remeasurement at each balance sheet date until exercised, and any change in fair value is recognized as a component of interest and other income, net in the Consolidated Statements of Operations and Comprehensive Loss. The fair value of the warrants issued by the Company has been estimated and is revalued at the end of each reporting period using a probability weighted Black-Scholes option pricing model.
Leases	Leases The Company determines at the inception of the lease if an arrangement is a lease. Operating leases are included in operating lease right-of-use (ROU) assets and operating lease liabilities in the Consolidated Balance Sheets. Finance leases are included in property and equipment and finance lease liabilities in the Consolidated Balance Sheets. ROU assets represent the right to use an underlying asset for the lease term and lease liabilities represent the obligation to make lease payments arising from the lease. Operating lease ROU assets and liabilities are recognized at the lease commencement date based on the present value of lease payments over the lease term. When the Company’s leases do not provide an implicit rate, an incremental borrowing rate is used based on the information available at the commencement dates in determining the present value of lease payments. The Company uses the implicit rate when readily determinable. The operating lease ROU assets also include any lease payments made and excludes lease incentives when paid by the Company or on the Company’s behalf. The Company’s lease terms may include the period covered by options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Lease expense for operating leases is recognized on a straight-line basis over the lease term. The Company has lease agreements with lease and non-lease components. The Company elected to not separate lease and non-lease components for all of its building leases. For vehicle leases, lease and non-lease components are accounted for separately. The Company also made an accounting policy election to recognize lease expense for leases with a term of 12 months or less on a straight-line basis over the lease term and not recognize ROU assets or lease liabilities for such leases.
Impairment of Right of Use Assets	Impairment of Right of Use Assets In accordance with ASC 360, Property, Plant and Equipment, management reviews the Company’s right of use assets for impairment annually or whenever events or changes in circumstances indicate that the carrying amount of an asset may not be fully recoverable. Events relating to recoverability may include significant unfavorable changes in business conditions, recurring losses, or a forecasted inability to achieve break-even operating results over an extended period. The Company determines the extent to which an asset may be impaired based upon its expectation of the asset’s future usability, as well as on a reasonable assurance that the future cash flows associated with the asset will be in excess of its carrying amount. If the total of the expected undiscounted future cash flows is less than the carrying amount of the asset, a loss is recognized for the difference between fair value and the carrying value of the asset. During the year ended December 31, 2023 , the Company vacated certain leased office space and as a result, the Company recorded an impairment charge against right of use assets of $ 0.7 million, recorded in the Consolidated Statements of Operations and Comprehensive Loss as general and administrative (G&A) expenses. No impairments were recorded in the year ended December 31, 2022 .
Property and equipment	Property and equipment Property and equipment is stated at cost less accumulated depreciation, and is depreciated using the straight-line method over the estimated useful life of the asset, which are as follows: Lab equipment 3 years Computer equipment 3 years Furniture and office equipment 3 - 8 years Vehicles 4 years Leasehold improvements Shorter of the useful life or Expenditures for repairs and maintenance of assets are charged to expense as incurred. Upon retirement or sale, the cost and related accumulated depreciation of assets disposed of are removed from the accounts and any resulting gain or loss is included in loss from operations.
Impairment of long-lived assets	Impairment of long-lived assets The Company regularly reviews the carrying amount of its property, equipment and intangible assets to determine whether indicators of impairment may exist which warrant adjustments to carrying values or estimated useful lives. If indications of impairment exist, projected future undiscounted cash flows associated with the asset are compared to the carrying amount to determine whether the asset’s value is recoverable. If the carrying value of the asset exceeds such projected undiscounted cash flows, the asset will be written down to its estimated fair value. No impairment charges were recorded during the years ended December 31, 2023 or 2022 .
Research and development expenses	Research and development expenses Research and development costs are expensed as incurred. Research and development expenses consist of costs incurred in performing research and development activities, including salaries, stock-based compensation and benefits, facilities costs, depreciation, and third-party license fees. Non-refundable prepayments for goods or services that will be used or rendered for future research and development activities are deferred and capitalized. In-process research and development (IPR&D) expense represents the costs to acquire technologies to be used in research and development that have not reached technological feasibility or have no alternative future uses and thus are expensed as incurred. IPR&D expense also includes upfront license fees and milestones paid to collaborators for technologies with no alternative use.
Collaborative arrangements	Collaborative arrangements The Company enters into collaboration arrangements with pharmaceutical and other partners, under which the Company may grant licenses to its collaboration partners to research and develop potential drug candidates. Consideration under these contracts may include an upfront payment, development, regulatory, sales and other milestone payments. Contractual payments received for research and development activities performed are recognized on a gross basis in revenue from collaboration arrangements. The Company may also perform research and development activities under the collaboration agreements where the Company may be granted licenses from its collaboration partners. Contractual payments to the other party in collaboration agreements and costs incurred by the Company are recognized on a gross basis in research and development expenses. Royalties and license payments are recorded as due. When the Company enters into collaboration arrangements, the Company assesses whether the arrangement falls within the scope of ASC 808, Collaborative Arrangements (ASC 808) based on whether the arrangement involves joint operating activities and whether both parties would be active participants and would be exposed to significant risks and rewards of the arrangement. To the extent that the arrangement falls within the scope of ASC 808, the Company assesses whether the payments between the parties fall within the scope of other accounting literature such as ASC 606, Revenue from Contracts with Customers (ASC 606). The upfront payments received during the years ended December 31, 2023 and 2022 were recorded on the Consolidated Balance Sheets as Deferred Revenue from Collaborations.
Revenue from contracts with customers	Revenue from contracts with customers The Company enters into revenue arrangements with certain partners. Consideration under these contracts may include an upfront payment, development, regulatory, sales and other milestone payments. Contractual payments received for research and development activities performed are recognized on a gross basis in Revenue from Customers. The Company may also perform research and development activities under the revenue agreements where the Company may be granted licenses from its partners. Contractual payments to the other party in revenue agreements and costs incurred by the Company are recognized on a gross basis in research and development expenses. Royalties and license payments are recorded as due. When the Company enters into revenue arrangements, the Company assesses whether the arrangement first falls within the scope of ASC 808, Collaborative Arrangements (ASC 808) based on whether the arrangement involves joint operating activities and whether both parties would be active participants and would be exposed to significant risks and rewards of the arrangement. If the arrangement does not fall into this literature, the Company then looks to ASC 606, Revenue from Contracts with Customers (ASC 606) to see whether the partner is considered a customer. The upfront payments received during the years ended December 31, 2023 and 2022 were recorded on the Consolidated Balance Sheets as Deferred Revenue from Customers.
Fair value measurements	Fair value measurements Certain assets and liabilities of the Company are carried at fair value under U.S. GAAP. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable: Level 1 —Quoted prices in active markets for identical assets or liabilities. Level 2 —Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data. Level 3 —Unobservable inputs that are supported by little or no market activity that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques.
Stock-based compensation	Stock-based compensation The Company’s stock-based awards consist of restricted stock awards and stock options. For stock-based awards issued to employees and nonemployees, the Company measures the estimated fair value of the stock-based awards on the date of grant and recognizes compensation expense for those awards over the requisite service period, which is generally the vesting period of the respective awards. The Company records expense for awards with service-based vesting using the straight-line method. The Company accounts for forfeitures as they occur. The Company classifies stock-based compensation expense in its Consolidated Statements of Operations and Comprehensive Loss in the same manner in which the award recipient’s cash compensation costs are classified. The fair value of each restricted stock award is determined based on the number of shares granted and the value of the Company’s common stock on the date of grant. The fair value of each stock option award is estimated on the date of grant using the Black-Scholes option pricing model. The Black-Scholes option-pricing model requires the use of a number of assumptions including the fair value of the common stock, expected volatility, risk-free interest rate, expected dividends, and expected term of the option. The Company determined the expected stock volatility using a weighted-average of the historical volatility of a group of guideline companies that issued options with substantially similar terms, and expects to continue to do so until such time as the Company has adequate historical data regarding the volatility of its own traded stock price. The expected term of the Company’s stock options has been determined utilizing the simplified method for awards that qualify as “plain-vanilla” options. 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. The Company has no t paid, and does not anticipate paying, cash dividends on its common stock; therefore, the expected dividend yield is assumed to be zero . The fair value of the Company’s 2020 Employee Stock Purchase Plan (the ESPP) is determined on the date the offering period begins using a Black-Scholes option-pricing model and similar assumptions for stock options as described above. See Note 9 for the assumptions used by the Company in determining the grant date fair value of stock-based awards granted, as well as a summary of the stock-based award activity under the Company’s stock-based compensation plan for years ended December 31, 2023 and 2022 .
Income taxes	Income taxes Deferred tax assets and liabilities are determined on the basis of the differences between the consolidated financial statements and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Changes in deferred tax assets and liabilities are recorded in the provision for income taxes. The Company assesses the likelihood that its deferred tax assets will be recovered from future taxable income and, to the extent it believes, based upon the weight of available evidence, that it is more likely than not that all or a portion of the deferred tax assets will not be realized, a valuation allowance is established. The Company accounts for uncertain tax positions recognized in the consolidated financial statements by prescribing a more-likely-than-not threshold for financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. The provision for income taxes includes the effects of any resulting tax reserves, or unrecognized tax benefits, that are considered appropriate as well as the related interest and penalties.
Net loss per share	Net loss per share Basic net loss per share attributable to common stockholders is calculated by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period, without consideration for potentially dilutive securities. The weighted-average number of shares of common stock outstanding includes the shares subject to the pre-funded warrants as per ASC 260, shares issuable for little or no cash consideration upon the satisfaction of certain conditions, shall be considered outstanding common shares. Diluted net loss per share attributable to common stockholders is computed by dividing the net loss attributable to common stockholders by the weighted-average number of common stock and potentially dilutive securities outstanding for the period. For purposes of the diluted net loss per share calculation, stock options, common stock subject to repurchase related to early exercise of stock options, unvested restricted stock subject to repurchase, common stock warrants and convertible notes are considered to be potentially dilutive securities. Accordingly, in periods in which the Company reports a net loss, diluted net loss per share is the same as basic net loss per share, since dilutive common shares are not assumed to have been issued if their effect is anti-dilutive.
Benefit plans	Benefit plans The Company has established a defined contribution savings plan for its employees in Aligos-US under Section 401(k) of the Internal Revenue Code, and a defined benefits plan for its employees in Aligos-Belgium. The Company uses the standard method for the recognition of the actuarial results as described in ASC 715. This means application of a 10 % corridor and amortization over the expected average remaining working lives of the employees. The plan contains benefits to the plan participant on the normal plan retirement date and benefits to the partner after death of the plan participant. This plan is recognized under ASC 715.
Recently issued accounting standards	Recently issued accounting standards In June 2016, the FASB issued ASU No. 2016-13. Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments (ASU 2016-13), which requires that financial assets measured at amortized cost be presented at the net amount expected to be collected. Currently, U.S. GAAP delays recognition of the full amount of credit losses until the loss is probable of occurring. Under this ASU, the income statement will reflect an entity’s current estimate of all expected credit losses. The measurement of expected credit losses will be based upon historical experience, current conditions, and reasonable and supportable forecasts that affect the collectability of the reported amount. In November 2018, the FASB issued ASU No. 2018-19, Codification Improvements to Topic 326, Financial Instruments—Credit Losses (ASU 2018-19), which clarifies that receivables from operating leases are accounted for using the lease guidance and not as financial instruments. In April 2019, the FASB issued ASU No. 2019-04, Codification Improvements to Topic 326, Financial Instruments—Credit Losses (ASU 2019-04), which clarifies the new expected credit loss methodology for loans, receivables and other financial assets, including recoveries and accrued interest on receivables. In November 2019, the FASB issued ASU No. 2019-11, Codification Improvements to Topic 326 , Financial Instruments—Credit Losses (ASU 2019-11), which clarifies guidance around how to report expected recoveries. The standard is effective for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years. Early adoption is permitted. The Company adopted this standard in fiscal year 2023 and there was not a material impact on its consolidated financial statements. In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes (ASU 2019-12). The guidance removes specific exceptions to the general principles in ASC 740, improves application of income tax-related guidance and reduces complexity related to the accounting for income taxes. The standard is effective for fiscal years beginning after December 15, 2020. Early adoption is permitted. The Company adopted this standard in fiscal year 2021 and there is not a material impact on its consolidated financial statements. From time to time, new accounting pronouncements are issued by FASB that the Company adopts as of the specified effective date. The Company qualifies as an “emerging growth company” as defined in the Jumpstart Our Business Startups Act of 2012 and has the option to not “opt out” of the extended transition related to complying with new or revised accounting standards. This means that when a standard is issued or revised and it has different application dates for public and nonpublic companies, the Company has the option to adopt the new or revised standard at the time nonpublic companies adopt the new or revised standard and can do so until such time that the Company either (i) irrevocably elects to “opt out” of such extended transition period or (ii) no longer qualifies as an emerging growth company.

Summary of significant accoun_3

Summary of significant accounting policies (Tables)	12 Months Ended
	Dec. 31, 2023
Accounting Policies [Abstract]
Summary of Estimated Useful Life of Asset	Property and equipment is stated at cost less accumulated depreciation, and is depreciated using the straight-line method over the estimated useful life of the asset, which are as follows: Lab equipment 3 years Computer equipment 3 years Furniture and office equipment 3 - 8 years Vehicles 4 years Leasehold improvements Shorter of the useful life or

Property and equipment (Tables)

Property and equipment (Tables)	12 Months Ended
	Dec. 31, 2023
Property, Plant and Equipment [Abstract]
Summary of Property and Equipment	The components of property and equipment were as follows as of December 31, 2023 and 2022: December 31, December 31, Leasehold improvements $ 6,101 $ 6,087 Lab equipment 5,830 6,179 Computer equipment 1,051 1,052 Furniture and office equipment 732 739 Vehicles 296 305 Asset under construction 4 22 Total, at cost 14,014 14,384 Accumulated depreciation ( 10,755 ) ( 9,568 ) Total, net $ 3,259 $ 4,816

Investments (Tables)

Investments (Tables)	12 Months Ended
	Dec. 31, 2023
Debt Securities, Available-for-Sale and Held-to-Maturity, after Allowance for Credit Loss [Abstract]
Summary of Available For Sale and Held to Maturity Securities Amortized Cost Gross Unrealized Gains Losses and Fair Value	As of December 31, 2022, amortized cost, gross unrealized gains and losses, and estimated fair values of total fixed-maturity securities were as follows: December 31, 2022 Gross Gross Amortized Unrealized Unrealized Estimated Cost Gain Loss Fair Value Available-for-sale securities: U.S. Treasury bonds $ 44,576 $ - $ ( 96 ) $ 44,480

Accrued liabilities (Tables)

Accrued liabilities (Tables)	12 Months Ended
	Dec. 31, 2023
Payables and Accruals [Abstract]
Summary of Accrued Liabilities	Accrued liabilities consisted of the following as of December 31: December 31, December 31, 2023 2022 Accrued compensation $ 6,673 $ 6,297 Accrued payables 7,144 8,203 Liability for early exercised stock options - 66 Other 3,025 1,473 Total $ 16,842 $ 16,039

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2023
Leases [Abstract]
Summary of Maturities of Lease Liabilities	Maturities of lease liabilities as of December 31, 2023, were as follows: Operating Finance Year ending December 31: 2024 $ 3,562 $ 63 2025 3,680 65 2026 3,801 44 2027 1,443 - 2028 161 - Thereafter - - 12,647 172 Less: imputed interest ( 1,750 ) 69 Present value of lease liabilities 10,897 241 Less: current portion ( 3,229 ) ( 10 ) Lease liabilities, net of current portion $ 7,668 $ 231
Summary of Components of lease Expense	The components of lease expense were as follows for the years ended December 31, 2023 and 2022: 2023 2022 Operating lease cost $ 2,321 $ 2,504 Finance lease cost: Amortization of right-of-use assets $ 84 $ 108 Interest on lease liabilities 11 13 Total finance lease cost $ 95 $ 121
Summary of Additional Information Related to the Leases	Additional information related to the Company’s leases was as follows as of December 31: December 31, December 31, 2023 2022 Operating Lease: Weighted-average remaining lease term (years) 3.38 4.21 Weighted-average discount rate 7.94 % 9.04 % Finance Lease: Weighted-average remaining lease term (years) 2.67 3.26 Weighted-average discount rate 5.57 % 5.15 %

Common Warrants and Pre Funde_2

Common Warrants and Pre Funded Warrants (Tables)	12 Months Ended
	Dec. 31, 2023
Class of Warrant or Right [Line Items]
Summary of Net Proceeds Received from Sale of Common Stock, Pre-Funded Warrants and Common Warrants	The Company used the with-and-without method to allocate the net proceeds received from the sale of the Common Stock, the Pre-Funded Warrants, and the Common Warrants on the Consolidated Balance Sheets as follows: As of October 25, 2023 Common Stock $ 18,641 Pre-Funded Warrants $ 48,079 Common Warrants $ 25,427 Total $ 92,147
Summary of Pre-funded Warrant Shares Outstanding	The following table summarizes information about shares issuable under the Pre-Funded Warrants outstanding at December 31, 2023: Pre-funded warrant shares outstanding Outstanding at January 1, 2023 - Issued 81,054,686 Outstanding at December 31, 2023 81,054,686 Exercisable at December 31, 2023 81,054,686
Summary of Common Warrant Liability	The following table sets forth a summary of the activities of the Company’s warrant liability, which represents a recurring measurement that is classified with Level 3 of the fair value hierarchy wherein the fair value is estimated using significant unobservable inputs: Common warrant liability Beginning liability as of January 1, 2023 - Common warrants issued 25,427 Change in fair value of liability as of December 31, 2023 2,169 Ending liability as of December 31, 2023 27,596 The fair value of the common warrants was measured using the Black Scholes option pricing model and will be remeasured each reporting period, and the change in fair value will be recorded in earnings. The assumptions that the Company used to determine the fair value at issuance and the reporting date of the common warrants granted to participants were as follows: 2023 Expected term (in years) 6.83 - 7.00 Risk-free interest rate 3.88 % - 4.98 % Dividend yield - Volatility 81.09 % - 82.80 %
Summary of Common Warrant Shares Outstanding	The following table summarizes information about shares issuable under the Common Warrants outstanding at December 31, 2023: Common warrant shares outstanding Outstanding at January 1, 2023 - Issued 56,241,973 Outstanding at December 31, 2023 56,241,973 Exercisable at December 31, 2023 56,241,973
Common Warrants [Member]
Class of Warrant or Right [Line Items]
Summary of Assumptions Used to Determine the fair value at Issuance and Reporting Date of Common Warrants Granted	The assumptions that the Company used to determine the fair value at issuance and the reporting date of the common warrants granted to participants were as follows:

Stock-based compensation (Table

Stock-based compensation (Tables)	12 Months Ended
	Dec. 31, 2023
Summary of Stock Options	Stock option activity during the year ended December 31, 2023 and 2022 was as follows: Shares Weighted- Weighted- Aggregate Outstanding as of December 31, 2021 5,692,514 $ 12.07 8.63 $ 16,763 Granted 5,090,824 $ 2.58 Exercised ( 12,896 ) $ 1.57 19 Forfeited or Expired ( 930,315 ) $ 8.72 Outstanding as of December 31, 2022 9,840,127 $ 7.49 8.28 $ — Granted 2,251,160 $ 1.19 Exercised ( 17,109 ) $ 1.34 $ — Forfeited or Expired ( 1,697,340 ) $ 6.00 Outstanding as of December 31, 2023 10,376,838 $ 6.38 6.90 $ — Options vested and expected to vest as of December 31, 2023 10,376,838 $ 6.38 6.90 $ — Options vested and exercisable as of December 31, 2023 6,049,770 $ 8.08 5.77 $ —
Summary of Stock Based Compensation Expense Was Allocated	Stock-based compensation expense was allocated as follows for the years ended December 31, 2023 and December 31, 2022: Year Ended December 31, 2023 2022 Research and development $ 6,843 $ 8,006 General and administrative 5,809 6,687 Total $ 12,652 $ 14,693
2020 Employee Stock Purchase Plan [Member]
Summary of Assumptions Used to Determine Grant-date Fair Value of Stock Options	The assumptions that the Company used to determine the grant-date fair value of shares granted to participants were as follows, disclosed on a grant date basis: 2023 2022 Expected term (in years) 0.5 - 2.0 years 0.5 - 2.0 years Risk-free interest rate 2.07 % - 5.38 % 1.54 % - 4.62 % Dividend yield - - Volatility 50.36 % - 64.26 % 57.21 % - 73.67 % Weighted-average estimated fair value of purchase rights $ 0.16 - $ 2.43 $ 0.28 - $ 2.46
Restricted Stock [Member]
Summary of Stock Options	The following table summarizes the Company’s restricted common stock activity for years ended December 31, 2023 and 2022: Number Weighted- Aggregate Issued and unvested as of December 31, 2021 89,054 $ 1.30 $ 117 Restricted stock awards granted - - - Restricted stock awards vested ( 89,054 ) 1.30 ( 117 ) Issued and unvested as of December 31, 2022 - - - Restricted stock awards granted 134,120 0.84 113 Restricted stock awards vested — - - Issued and unvested as of December 31, 2023 134,120 $ 0.84 $ 113
Stock Option [Member]
Summary of Assumptions Used to Determine Grant-date Fair Value of Stock Options	The assumptions that the Company used to determine the grant-date fair value of stock options granted to Participants were as follows, pre sented on a weighted-average basis: 2023 2022 Expected term (in years) 6.00 5.95 Risk-free interest rate 3.83 % 2.20 % Dividend yield - - Volatility 76.65 % 80.41 %

Fair value measurements (Tables

Fair value measurements (Tables)	12 Months Ended
	Dec. 31, 2023
Summary of fair value of the financial instruments that are measured at fair value on a recurring basis	The following tables present the fair value of the Company’s financial instruments that are measured or disclosed at fair value on a recurring basis: Fair Value Measurements Level 1 Level 2 Level 3 Assets: Cash equivalents $ 135,704 $ - $ - Liabilities: Warrant liability ( 27,596 ) $ 135,704 $ - $ ( 27,596 ) Fair Value Measurements Level 1 Level 2 Level 3 Assets: Cash equivalents $ 81,347 $ - $ - U.S. Treasury bonds 44,480 - - $ 125,827 $ - $ -

License and Collaboration Agr_2

License and Collaboration Agreements (Tables)	12 Months Ended
	Dec. 31, 2023
License And Collaboration Agreements [Abstract]
Schedule of Deferred Revenue from Collaborative Arrangements	Changes in deferred revenue balances arose as a result of the Company recognizing the following revenue from collaborative arrangements during the periods below (in thousands): As of December 31, 2023 2022 Deferred revenue from collaborations as of January 1 $ 8,743 $ 7,641 Consideration received in the period $ 679 $ 15,009 Revenue from collaborations recognized in the period $ ( 9,338 ) $ ( 13,907 ) Deferred revenue from collaborations as of December 31 $ 84 $ 8,743

Revenue from contracts with c_2

Revenue from contracts with customers (Tables)	12 Months Ended
	Dec. 31, 2023
Revenue from Contract with Customer [Abstract]
Schedule of Deferred Revenue from Customers	Changes in deferred revenue balances arose as a result of the Company recognizing the following revenue from customers during the periods below (in thousands): As of December 31, 2023 2022 Deferred revenue from customers as of January 1 $ 700 $ — Consideration received in the period $ 6,715 $ 700 Revenue from customers recognized in the period $ ( 6,191 ) $ — Deferred revenue from customers as of December 31 $ 1,224 $ 700

Income taxes (Tables)

Income taxes (Tables)	12 Months Ended
	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Schedule of Components of Current Provision for Income Taxes	The components of the current provision for income taxes were as follows for the years ended December 31, 2023 and 2022: 2023 2022 Current: State $ - $ - Federal - - Foreign 795 106 Total current provision for income taxes $ 795 $ 106 Deferred: State $ - $ - Federal - - Foreign - - Total deferred provision for income taxes $ - $ -
Schedule of Expected Income Tax (Benefit) Computed Using Federal Statutory Income Tax Rate to Company's Effective Income Tax Rate	A reconciliation of the expected income tax (benefit) computed using the federal statutory income tax rate to the Company’s effective income tax rate is as follows for the years ended December 31, 2023 and 2022: 2023 2022 Income tax computed at federal statutory rate 21.00 % 21.00 % State taxes, net of federal benefit 6.71 % 6.95 % R&D credit carryovers 6.35 % 1.25 % Change in valuation allowance 86.68 % - 26.32 % Stock based compensation - 2.30 % - 1.08 % Permanent differences - 0.63 % - 1.91 % Section 382 limitation - 117.98 % 0.00 % Foreign tax - 0.76 % 0.00 % Effective income tax rate - 0.93 % - 0.11 %
Schedule of Deferred Tax Assets And Liabilities	The components of the deferred tax assets and liabilities were as follows at December 31: 2023 2022 Deferred tax assets: Net operating loss carryforward $ 3,491 $ 82,775 Operating lease liabilities 3,280 4,057 Tax credits 941 8,025 Other accruals and reserves 1,622 1,398 Stock-based compensation 2,714 2,055 Deferred revenue 24 27 Capitalized Sec 174 costs 23,962 14,138 Other 577 253 36,611 112,728 Valuation allowance ( 34,235 ) ( 109,560 ) Net deferred tax assets $ 2,376 $ 3,168 Deferred tax liabilities: Right of use assets ( 2,078 ) ( 2,803 ) Stock-based compensation - - Property and equipment ( 298 ) ( 365 ) Total deferred tax liabilities $ ( 2,376 ) $ ( 3,168 ) Total deferred income taxes $ - $ -
Summary of Changes to Unrecognized Tax Benefits	2023 2022 Balance, beginning of the period $ 3,100 $ 2,441 (Decrease) Increase related to prior year positions ( 3,100 ) 687 Increase (Decrease) related to current year positions 99 ( 28 ) Balance, end of the period $ 99 $ 3,100

Net loss per share (Tables)

Net loss per share (Tables)	12 Months Ended
	Dec. 31, 2023
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	The following table summarizes the computation of basic and diluted net loss per share of the Company: Year Ended December 31, 2023 2022 Net loss $ ( 87,679 ) $ ( 96,046 ) Weighted average common stock outstanding, 64,260,588 42,695,227 Net loss per share - basic and diluted $ ( 1.36 ) $ ( 2.25 )
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	The Company excluded the following potential shares of Common Stock, presented based on amounts outstanding at each period end, from the computation of diluted net loss per share for the periods indicated because including them would have had an anti-dilutive effect: Year Ended December 31, 2023 2022 Options to purchase common stock 10,376,838 9,840,127 Unvested restricted stock 134,120 - Warrants to purchase common stock 56,241,973 - 66,752,931 9,840,127

Organization - Additional Infor

Organization - Additional Information (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Cash, cash equivalent and investments	$ 135,700
Accumulated deficit	$ 486,797	$ 399,118

Summary of significant accoun_4

Summary of significant accounting policies - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2023 USD ($) Segment	Dec. 31, 2022 USD ($)
Financing Sources [Line Items]
Re-measurement loss	$ 45,700	$ 42,000
Number of reportable segments | Segment	1
Product revenue	$ 6,191,000
Pre-product revenue	0
Property and equipment, net	$ 3,259,000	4,816,000
Cash equivalent qualification, description	The Company considers all highly liquid investments purchased with original maturities of 90 days or less at acquisition to be cash equivalents.
Restricted cash	$ 70,000	$ 115,000
Investments, maturity period	1 year 6 months	1 year 6 months
Impairment of right of use assets	$ 724,000	$ 0
Other than temporary impairment losses, investments	0	0
Impairment of long lived assets	0	0
Dividends, common stock, cash	$ 0
Expected dividend yield	0%
Percentage of expected average remaining working lives of employees	10%
Investments	$ 0
Reduction to R&D expenses	1,600,000	0
Grant by the National Institute of Health (NIH) for Research to Target Coronaviruses
Financing Sources [Line Items]
Government grants / contract awarded	$ 1,400,000	$ 1,100,000
Government Assistance, Statement of Income or Comprehensive Income [Extensible Enumeration]	Research and Development Expense	Research and Development Expense
Grant by the National Institute of Allergies and Infectious Diseases (NIAID) for Research to Target Coronaviruses
Financing Sources [Line Items]
Government grants / contract awarded	$ 8,500,000
Government Assistance, Statement of Income or Comprehensive Income [Extensible Enumeration]	Research and Development Expense
Government contract, duration	2 years
General and Administrative (G&A) Expenses
Financing Sources [Line Items]
Impairment of right of use assets	$ 700,000
US
Financing Sources [Line Items]
Property and equipment, net	2,900,000	$ 4,100,000
Belgium
Financing Sources [Line Items]
Property and equipment, net	$ 300,000	$ 700,000

Summary of significant accoun_5

Summary of significant accounting policies - Summary of Estimated Useful Life of Asset (Detail)	12 Months Ended
	Dec. 31, 2023
Property Plant And Equipment [Line Items]
Property, Plant, and Equipment, Useful Life, Term, Description [Extensible Enumeration]	us-gaap:UsefulLifeTermOfLeaseMember
Lab Equipment [Member]
Property Plant And Equipment [Line Items]
Estimated useful life of asset	3 years
Computer Equipment [Member]
Property Plant And Equipment [Line Items]
Estimated useful life of asset	3 years
Vehicles [Member]
Property Plant And Equipment [Line Items]
Estimated useful life of asset	4 years
Leasehold Improvements [Member]
Property Plant And Equipment [Line Items]
Estimated useful life of asset	Shorter of the useful life orremaining lease term
Minimum [Member] | Furniture and Office Equipment [Member]
Property Plant And Equipment [Line Items]
Estimated useful life of asset	3 years
Maximum [Member] | Furniture and Office Equipment [Member]
Property Plant And Equipment [Line Items]
Estimated useful life of asset	8 years

Property and equipment - Summar

Property and equipment - Summary of Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Total, at cost	$ 14,014	$ 14,384
Accumulated depreciation	(10,755)	(9,568)
Total, net	3,259	4,816
Leasehold improvements [Member]
Property, Plant and Equipment [Line Items]
Total, at cost	6,101	6,087
Lab equipment [Member]
Property, Plant and Equipment [Line Items]
Total, at cost	5,830	6,179
Computer equipment [Member]
Property, Plant and Equipment [Line Items]
Total, at cost	1,051	1,052
Furniture and office equipment [Member]
Property, Plant and Equipment [Line Items]
Total, at cost	732	739
Vehicles [Member]
Property, Plant and Equipment [Line Items]
Total, at cost	296	305
Asset under construction [Member]
Property, Plant and Equipment [Line Items]
Total, at cost	$ 4	$ 22

Property and equipment - Additi

Property and equipment - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 1,559	$ 2,306

Investments - Summary of Availa

Investments - Summary of Available For Sale and Held to Maturity Securities Amortized Cost Gross Unrealized Gains Losses and Fair Value (Detail) - USD ($)	Dec. 31, 2023	Dec. 31, 2022
Schedule Of Available For Sale And Held To Maturity Securities Amortised Cost Gross Unrealised Gains Losses And Fair Value [Line Items]
Available-for-sale securities, Estimated Fair Value	$ 0
U.S. Treasury bonds [Member]
Schedule Of Available For Sale And Held To Maturity Securities Amortised Cost Gross Unrealised Gains Losses And Fair Value [Line Items]
Available-for-sale securities, Amortized Cost		$ 44,576,000
Available-for-sale securities, Gross Unrealized Loss		(96,000)
Available-for-sale securities, Estimated Fair Value		$ 44,480,000

Investments - Additional Inform

Investments - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Investment In Available For Sale And Held To Maturity Securities [Line Items]
Available for sale securities	$ 0
Interest income	$ 4,300,000	$ 1,500,000

Accrued liabilities - Summary o

Accrued liabilities - Summary of Accrued Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Payables and Accruals [Abstract]
Accrued compensation	$ 6,673	$ 6,297
Accrued payables	7,144	8,203
Liability for early exercised stock options		66
Other	3,025	1,473
Total	$ 16,842	$ 16,039

Accrued liabilities - Additiona

Accrued liabilities - Additional Information (Details) - USD ($)	Dec. 31, 2024	Dec. 31, 2023
Accrued Liabilities [Line Items]
Accrued compensation		$ 300,000
Forecast [Member]
Accrued Liabilities [Line Items]
Accrued compensation	$ 0

Leases - Additional Information

Leases - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($) ft²
Lessee Lease Description [Line Items]
Operating lease, payments	$ 3,600,000	$ 3,400,000
Finance lease right of use assets	700,000	700,000
Finance lease right of use assets accumulated amortization	400,000	300,000
Operating lease, term of contract			5 years
Operating lease area of office space | ft²			12,000
Operating lease renewal option			5 years
Operating lease rental payments			$ 2,700,000
Impairment of right of use assets	$ 724,000	$ 0
Minimum [Member]
Lessee Lease Description [Line Items]
Operating and finance lease remaining lease term	3 years
Operating lease option to extend	5 years
Maximum [Member]
Lessee Lease Description [Line Items]
Operating and finance lease remaining lease term	5 years
Operating lease option to extend	8 years

Leases - Summary of Maturities

Leases - Summary of Maturities of Lease Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Operating Lease
2024	$ 3,562
2025	3,680
2026	3,801
2027	1,443
2028	161
Lessee, Operating Lease, Liability, to be Paid	12,647
Less: imputed interest	(1,750)
Present value of lease liabilities	10,897
Less: current portion	(3,229)	$ (3,035)
Lease liabilities net of current portion	7,668	9,201
Finance Lease
2024	63
2025	65
2026	44
Finance Lease, Liability, Payment, Due	172
Less: imputed interest	69
Present value of lease liabilities	241
Less: current portion	(10)	(108)
Lease liabilities net of current portion	$ 231	$ 230

Leases - Summary of Components

Leases - Summary of Components of Lease Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Lease, Cost [Abstract]
Operating lease cost	$ 2,321	$ 2,504
Finance lease cost:
Amortization of right-of-use assets	84	108
Interest on lease liabilities	11	13
Total finance lease cost	$ 95	$ 121

Leases - Summary of Additional

Leases - Summary of Additional Information Related to the leases (Detail)	Dec. 31, 2023	Dec. 31, 2022
Schedule Of Additional Information Related To The Leases [Abstract]
Weighted-average remaining lease term (years)	3 years 4 months 17 days	4 years 2 months 15 days
Weighted-average discount rate	7.94%	9.04%
Weighted-average remaining lease term (years)	2 years 8 months 1 day	3 years 3 months 3 days
Weighted-average discount rate	5.57%	5.15%

Derivative liabilities and rede

Derivative liabilities and redeemable convertible preferred stock liability - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Derivative Liabilities And Convertible Preferred Stock Liability [Line Items]
Change in fair value of warrant liability	$ 2,169
Preferred Stock, Shares Issued	0	0

Capital stock - Additional Info

Capital stock - Additional Information (Detail) - $ / shares	Dec. 23, 2019	Dec. 31, 2023	Dec. 31, 2022	Oct. 20, 2020
Number of shares of common stock authorized		320,000,000	320,000,000	320,000,000
Number of shares of preferred stock authorized		10,000,000	10,000,000	10,000,000
Preferred stock authorized par value		$ 0.0001	$ 0.0001	$ 0.0001
Common stock voting right	one
Preferred Stock, Shares Issued		0	0
Voting Common Stock [Member]
Number of shares of common stock authorized				300,000,000
Non-Voting Common Stock [Member]
Number of shares of common stock authorized				20,000,000

Common Warrants and Pre Funde_3

Common Warrants and Pre Funded Warrants - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended
	Oct. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Class of Warrant or Right [Line Items]
Shares issued (in Shares)	31,429,266	75,096,906	42,922,980
Common stock, par value	$ 0.0001	$ 0.0001	$ 0.0001
Gross Proceeds	$ 92.1
Net proceeds	$ 86.2
2023 Pre-Funded Warrants
Class of Warrant or Right [Line Items]
Number of prefunded warrants to be issued	81,054,686
Exercise price of warrant per share	$ 0.0001
Price per share of warrants	$ 0.7568
Common Warrants
Class of Warrant or Right [Line Items]
Warrants to purchase common stock	56,241,973
Warrant expiration date	Oct. 25, 2030
Exercise price of warrant per share	$ 0.7568

Common Warrants and Pre Funde_4

Common Warrants and Pre Funded Warrants - Summary of Net Proceeds Received from Sale of Common Stock, Pre-Funded Warrants and Common Warrants (Details) - USD ($) $ in Thousands		1 Months Ended
	Oct. 25, 2023	Oct. 31, 2023
Class of Warrant or Right [Line Items]
Common Warrants		$ 86,200
October 2023 Securities Purchase Agreement
Class of Warrant or Right [Line Items]
Common Stock	$ 18,641
Pre-Funded Warrants	48,079
Common Warrants	25,427
Total	$ 92,147

Common Warrants and Pre Funde_5

Common Warrants and Pre Funded Warrants - Summary of Pre-funded Warrant Shares Outstanding (Details) - October 2023 Securities Purchase Agreement	12 Months Ended
	Dec. 31, 2023 shares
Class of Warrant or Right [Line Items]
Beginning balance, shares	0
Issued	81,054,686
Ending balance, shares	81,054,686
Exercisable at December 31, 2023	81,054,686

Common Warrants and Pre Funde_6

Common Warrants and Pre Funded Warrants - Summary of Common Warrant Liability (Details) - October 2023 Securities Purchase Agreement - Level 3 [Member]	12 Months Ended
	Dec. 31, 2023 shares
Class of Warrant or Right [Line Items]
Beginning balance, shares	0
Common warrants issued	25,427
Change in fair value of liability as of December 31, 2023	2,169
Ending balance, shares	27,596

Common Warrants and Pre Funde_7

Common Warrants and Pre Funded Warrants - Summary of Assumptions Used to Determine the fair value at Issuance and Reporting Date of Common Warrants Granted (Details) - Common Warrants [Member]	Dec. 31, 2023
Expected Term [Member] | Minimum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Alternative Investment, Measurement Input	6.83
Expected Term [Member] | Maximum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Alternative Investment, Measurement Input	7
Risk-free Interest Rate [Member] | Minimum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Alternative Investment, Measurement Input	0.0388
Risk-free Interest Rate [Member] | Maximum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Alternative Investment, Measurement Input	0.0498
Volatility [Member] | Minimum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Alternative Investment, Measurement Input	0.8109
Volatility [Member] | Maximum [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Alternative Investment, Measurement Input	0.828

Common Warrants and Pre Funde_8

Common Warrants and Pre Funded Warrants - Summary of Common Warrant Shares Outstanding (Details) - October 2023 Securities Purchase Agreement	12 Months Ended
	Dec. 31, 2023 shares
Class of Warrant or Right [Line Items]
Beginning balance, shares	0
Issued	56,241,973
Ending balance, shares	56,241,973
Exercisable at December 31, 2023	56,241,973

Stock-based Compensation - Addi

Stock-based Compensation - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2023 USD ($) $ / shares shares	Dec. 31, 2022 USD ($) $ / shares shares	Dec. 31, 2018 shares	Oct. 15, 2020 shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based payment exercise price description	The exercise price for incentive stock options is at least 100% of the fair market value on the date of grant for stockholders owning less than 10% of the voting power of all classes of stock, or at least 110% of the fair market value for stockholders owning more than 10% of the voting power of all classes of stock. Options generally expire in 10 years and vest over periods determined by the Board, generally 48 months.
Share based compensation expense recognized tax benefit | $	$ 0	$ 0
Shares of common stock held by employees subject to repurchase	0	28,711
Aggregate price for share repurchase | $		$ 100,000
Less than 10% [Member] | Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Exercise price for incentive stock options as of fair market value	1
More Than 10% [Member] | Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Exercise price for incentive stock options as of fair market value	1.10
Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expiration period	10 years
Common stock vesting period	48 months
Share based compensation expense | $	$ 11,800,000	$ 13,500,000
Share based payment unrecognized stock based payment expenses | $	$ 9,400,000
Share based payment unrecognized expenses expected vesting peroiod	1 year 4 months 13 days
Share based payments weighted-average grant date fair value | $ / shares	$ 0.82	$ 1.8
Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expiration period	3 years
Share based compensation expense | $	$ 31,000	$ 100,000
Share based payment unrecognized stock based payment expenses | $	$ 100,000	0
Share based payment unrecognized expenses expected vesting peroiod	1 year 1 month 20 days
Restricted stock awards rights vesting percentage	33%
Restricted stock awards rights vesting	1/36
Restricted stock awards granted	134,120		502,964
2018 Equity incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based payment Common stock shares authorised	4,913,665
Share based payment awards granted	4,279,693
Common stock available for future grant	0
2018 Equity incentive Plan [Member] | Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expiration period	4 years
Restricted stock awards rights vesting percentage	25%
Restricted stock awards rights vesting	1/48
2020 Incentive Award Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based payment awards granted	11,173,830
Common stock available for future grant	1,992,349
2020 Employee Stock Purchase Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock available for future grant	993,016			368,901
Share based compensation expense | $	$ 900,000	$ 1,300,000

Stock-based Compensation - Summ

Stock-based Compensation - Summary of Assumptions Used to Determine Grant-date Fair Value of Stock Options (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Expected dividend yield	0%
2020 Employee Stock Purchase Plan [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Expected dividend yield
2020 Employee Stock Purchase Plan [Member] | Minimum [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Expected term (in years)	6 months	6 months
Risk-free interest rate, minimum	2.07%	1.54%
Volatility, minimum	50.36%	57.21%
Weighted-average estimated fair value of purchase rights	$ 0.16	$ 0.28
2020 Employee Stock Purchase Plan [Member] | Maximum [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Expected term (in years)	2 years	2 years
Risk-free interest rate, maximum	5.38%	4.62%
Volatility, maximum	64.26%	73.67%
Weighted-average estimated fair value of purchase rights	$ 2.43	$ 2.46
Stock Option [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Expected term (in years)	6 years	5 years 11 months 12 days
Risk-free interest rate	3.83%	2.20%
Volatility	76.65%	80.41%

Stock-based Compensation - Su_2

Stock-based Compensation - Summary of Stock Options (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Stock Option [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Number of options - Beginning balance	9,840,127	5,692,514
Number of options, Granted	2,251,160	5,090,824
Number of options, Exercised	(17,109)	(12,896)
Number of options, Forfeited or expired	(1,697,340)	(930,315)
Number of options - Ending balance	10,376,838	9,840,127	5,692,514
Number of options vested and expected to vest	10,376,838
Number of options vested and exercisable	6,049,770
Weighted average exercise price per share - Beginning balance	$ 7.49	$ 12.07
Weighted average exercise price per share Granted	1.19	2.58
Weighted average exercise price per share Exercised	1.34	1.57
Weighted average exercise price per share Forfeited or expired	6	8.72
Weighted Average Exercise Price Per Share - Ending balance	6.38	$ 7.49	$ 12.07
Weighted average exercise price Options per share vested and expected to vest	6.38
Weighted average exercise price options per share vested and exercisable	$ 8.08
Weighted- Average Remaining Contractual Term, Outstanding	6 years 10 months 24 days	8 years 3 months 10 days	8 years 7 months 17 days
Weighted- Average Remaining Contractual Term, Options vested and expected to vest	6 years 10 months 24 days
Weighted- Average Remaining Contractual Term, Options vested and exercisable	5 years 9 months 7 days
Aggregate Intrinsic Value - Options outstanding			$ 16,763
Aggregate Intrinsic Value - Exercised		$ 19
Restricted Stock [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Number of awards - Beginning balance	0	89,054
Number of awards, vested		(89,054)
Number of awards - Ending balance	134,120	0	89,054
Weighted average granted fair date value per share - Beginning balance		$ 1.3
Weighted average granted fair date value per share, granted	$ 0.84
Weighted average granted fair date value per share, vested		$ 1.3
Weighted average granted fair date value per share - Ending balance	$ 0.84		$ 1.3
Aggregate Fair Value, Beginning balance		$ 117
Aggregate Fair Value, granted	$ 113
Aggregate Fair Value, vested		$ (117)
Aggregate Fair Value, Ending balance	$ 113		$ 117

Stock-based Compensation - Su_3

Stock-based Compensation - Summary of Stock Based Compensation Expense Was Allocated (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Allocated Share Based Compensation Expense	$ 12,652	$ 14,693
Research and Development [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Allocated Share Based Compensation Expense	6,843	8,006
General and Administrative [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Allocated Share Based Compensation Expense	$ 5,809	$ 6,687

Fair value measurements - Summa

Fair value measurements - Summary of Fair Value of the Financial Instruments that are Measured at Fair Value on a Recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Level 1 [Member]
Assets:
Cash equivalents	$ 135,704	$ 81,347
Fair value, assets		125,827
Liabilities:
Fair Value, Net Asset (Liability), Total	135,704
Level 2 [Member]
Assets:
Cash equivalents	0	0
Fair value, assets		0
Liabilities:
Fair Value, Net Asset (Liability), Total	0
Level 3 [Member]
Assets:
Cash equivalents	0	0
Fair value, assets		0
Liabilities:
Fair Value, Net Asset (Liability), Total	(27,596)
Warrant Liability [Member] | Level 3 [Member]
Liabilities:
Fair value, Liabilities	$ (27,596)
U.S. Treasury bonds [Member] | Level 1 [Member]
Assets:
Fair value, assets		44,480
U.S. Treasury bonds [Member] | Level 2 [Member]
Assets:
Fair value, assets		0
U.S. Treasury bonds [Member] | Level 3 [Member]
Assets:
Fair value, assets		$ 0

License and collaboration agr_3

License and collaboration agreements - Additional Information (Detail) - USD ($)			1 Months Ended				12 Months Ended
	Jun. 25, 2020	Dec. 19, 2018	Jan. 31, 2022	Dec. 31, 2020	Jun. 30, 2020	Apr. 30, 2020	Dec. 31, 2023	Dec. 31, 2022	Jun. 30, 2018
Expense related to milestone payments							$ 2,000,000	$ 0
Revenue recognized from collaborative arrangements on upfront payment							(9,338,000)	(13,907,000)
Revenue recognized from collaborative arrangements							$ 0	0
KU Leuven [Member]
Collaboration expire period	2 years 6 months
Emory license agreement [Member] | Emory university [Member]
Non-refundable payment					$ 200,000
Long term purchase commitment additional obligation to be paid					35,000
Research plan funding amount					$ 300,000
Research plan expiry period					1 year
Long term purchase commitment period description							The research plan was set to terminate one year from the effective date of June 2020 but the Company exercised its option to extend it for a second year.
Expense related to milestone payments							$ 0	0
Payments for royalties							0	0
General expenses recognized							400,000	200,000
Emory license agreement [Member] | Emory university [Member] | Maximum [Member]
Aggregate payments									$ 125,000,000
Luxna license agreement [Member] | Luxna biotech Co Ltd [Member]
Expense related to milestone payments							0	0
Payments for royalties							$ 0	0
Luxna license agreement [Member] | Luxna biotech Co Ltd [Member] | Maximum [Member]
Aggregate payments		$ 55,500,000
Luxna license agreement [Member] | Research and Development [Member] | Luxna biotech Co Ltd [Member]
Upfront license fees paid		$ 600,000
Non-refundable payment						$ 200,000
Katholieke Universiteit Leuven License Agreement [Member] | Katholieke Universiteit Leuven [Member]
Non-refundable payment	$ 30,000,000
Long term purchase commitment period description							Unless terminated earlier by either party, the agreement shall continue until the expiration of the last to expire royalty term, which is the later of the expiration or termination of the last valid patent claim covering the manufacture, use, sale or importation of the licensed product in a particular country or 10 years after the first commercial sale of a licensed product.
First commercial sale of a licensed product period	10 years
Katholieke Universiteit Leuven License Agreement [Member] | Katholieke Universiteit Leuven [Member] | Maximum [Member]
Non-refundable payment	$ 32,000,000
Merck License and Research Collaboration | Merck
Upfront payment received			$ 15,000,000	$ 12,000,000
Additional upfront payment received			15,000,000
Merck License and Research Collaboration | Merck | Maximum [Member]
Milestone payments and royalties receivable			$ 460,000,000	$ 458,000,000
Merck License and Research Collaboration First Amendment | Merck
Revenue recognized from collaborative arrangements on upfront payment							$ 9,300,000	13,900,000
Revenue recognized from collaborative arrangements							$ 0	$ 0

License and Collaboration Agr_4

License and Collaboration Agreements - Summary of Deferred Revenue from Collaborative Arrangements (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
License And Collaboration Agreements [Abstract]
Deferred revenue from collaborations as of January 1	$ 8,743	$ 7,641
Consideration received in the period	679	15,009
Revenue from collaborations recognized in the period	(9,338)	(13,907)
Deferred revenue from collaborations as of December 31	$ 84	$ 8,743

Revenue from contracts with c_3

Revenue from contracts with customers - Additional Information (Detail) - USD ($)	1 Months Ended	12 Months Ended
	May 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Revenue from customers related to upfront payments		$ 6,200,000	$ 0
Revenue from customers related to milestone payments		$ 0	$ 0
Amoytop License and Research Collaboration [Member] | Amoytop [Member]
Upfront payment received	$ 7,000,000
Withholding taxes	1,100,000
Amoytop License and Research Collaboration [Member] | Amoytop [Member] | Maximum [Member]
Milestone payments and royalties receivable	$ 109,000,000

Revenue from contracts with c_4

Revenue from contracts with customers - Schedule of Deferred Revenue from customers (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Revenue from Contract with Customer [Abstract]
Deferred revenue from customers as of January 1	$ 700
Consideration received in the period	6,715	$ 700
Revenue from customers recognized in the period	(6,191)
Deferred revenue from customers as of December 31	$ 1,224	$ 700

Income Taxes - Schedule of Comp

Income Taxes - Schedule of Components of Current Provision for Income Taxes (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Current:
Foreign	$ 795,000	$ 106,000
Total current provision for income taxes	795,000	106,000
Deferred:
Total deferred provision for income taxes	$ 0	$ 0

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Contingency [Line Items]
Deferred provision for income taxes	$ 0	$ 0
Increase (decreased) in valuation allowance	$ (75,300,000)	25,300,000
Deferred tax assets net operating loss carryforwards ownership change in percentage	50%
Offset percentage of taxable income	80%
Unrecognized tax benefits, income tax penalties and interest expense	$ 0	0
Unrecognized tax benefits	99,000	$ 3,100,000	$ 2,441,000
Uncertain tax positions related to liability	0
Australia
Income Tax Contingency [Line Items]
Deferred tax assets, research and development tax credit carryforwards	700,000
NOL carryforwards	6,000,000
Federal [Member]
Income Tax Contingency [Line Items]
Net operating loss carryforwards	$ 3,700,000
Deferred tax assets net operating loss carryforwards expiration year	2043
Deferred tax assets, research and development tax credit carryforwards	$ 200,000
Tax credit research and development carryforward expiration year	2043
Net operating losses written off	$ 288,600,000
Research and development credit carryforwards written off	9,700,000
State [Member]
Income Tax Contingency [Line Items]
Net operating loss carryforwards	12,700,000
Deferred tax assets, research and development tax credit carryforwards	200,000
Net operating losses written off	407,100,000
Research and development credit carryforwards written off	$ 4,800,000

Income Taxes - Schedule of Expe

Income Taxes - Schedule of Expected Income Tax (Benefit) Computed Using Federal Statutory Income Tax Rate to Company's Effective Income Tax Rate (Detail)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Income tax computed at federal statutory rate	21%	21%
State taxes, net of federal benefit	6.71%	6.95%
R&D credit carryovers	6.35%	1.25%
Change in valuation allowance	86.68%	(26.32%)
Stock based compensation	(2.30%)	(1.08%)
Permanent differences	(0.63%)	(1.91%)
Section 382 limitation	(117.98%)	0%
Foreign tax	(0.76%)	0%
Effective income tax rate	(0.93%)	(0.11%)

Income Taxes - Components of De

Income Taxes - Components of Deferred Tax Assets And Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Deferred tax assets:
Net operating loss carryforward	$ 3,491	$ 82,775
Operating lease liabilities	3,280	4,057
Tax credits	941	8,025
Other accruals and reserves	1,622	1,398
Stock-based compensation	2,714	2,055
Deferred revenue	24	27
Capitalized SEC 174 costs	23,962	14,138
Other	577	253
Total deferred tax assets	36,611	112,728
Valuation allowance	(34,235)	(109,560)
Net deferred tax assets	2,376	3,168
Deferred tax liabilities:
Right of use assets	(2,078)	(2,803)
Property and equipment	(298)	(365)
Total deferred tax liabilities	$ (2,376)	$ (3,168)

Income Taxes - Summary of Chang

Income Taxes - Summary of Changes to Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balance	$ 3,100	$ 2,441
(Decrease) Increase related to prior year positions	(3,100)	687
Increase (Decrease) related to current year positions	99	(28)
Ending balance	$ 99	$ 3,100

Benefit plans - Additional Info

Benefit plans - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan, matching amount		$ 800,000	$ 900,000
Regular Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan, matching percentage		1.75%
Net periodic benefit cost		$ 200,000	300,000
Projected benefit obligation		1,200,000	1,100,000
Projected benefit obligation, plan assets		1,200,000	1,000,000
Net pension liability		100,000	100,000
Actuarial gain (loss)		40,000	101,000
Estimates future benefit payments from 2025 to 2028		300,000
Estimates future benefit payments, 2029 and thereafter		$ 800,000
Regular Pension Plan [Member] | Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Company contributions	$ 100,000
Top Hat Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan legal yield guarantee percent		1.75%
Net periodic benefit cost		$ 200,000	200,000
Projected benefit obligation		2,000,000	1,700,000
Projected benefit obligation, plan assets		1,800,000	1,500,000
Net pension liability		200,000	200,000
Actuarial gain (loss)		3,000	$ 60,000
Estimates future benefit payments from 2025 to 2028		500,000
Estimates future benefit payments, 2029 and thereafter		$ 1,100,000
Top Hat Plan [Member] | Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Company contributions	$ 200,000

Net loss per share - Schedule o

Net loss per share - Schedule of Earnings Per Share Basic and Diluted (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Earnings Per Share [Abstract]
Net loss	$ (87,679)	$ (96,046)
Weighted average shares of common stock, basic	64,260,588	42,695,227
Weighted average shares of common stock, diluted	64,260,588	42,695,227
Net loss per share, basic	$ (1.36)	$ (2.25)
Net loss per share, diluted	$ (1.36)	$ (2.25)

Net loss per share - Schedule_2

Net loss per share - Schedule of Antidilutive Securities Excluded From Computation of Earnings Per Share (Detail) - shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	66,752,931	9,840,127
Options to purchase common stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	10,376,838	9,840,127
Unvested restricted stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	134,120	0
Warrants to purchase common stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	56,241,973	0

Subsequent events - Additional

Subsequent events - Additional Information (Detail) - Subsequent Event [Member]	1 Months Ended
	Jan. 31, 2024 $ / shares shares
Subsequent Event [Line Items]
Number of options cancelled in connection with exchange offer	3,880,332
Number of replacement options granted in connection with exchange offer	1,906,153
Common stock vesting period	1 year
Replacement Option One [Member]
Subsequent Event [Line Items]
Options tendered	1.4
Replacement Option Two [Member]
Subsequent Event [Line Items]
Options tendered	3.4
Eligible options tendered for replacement option, value | $ / shares	$ 11.86
Minimum [Member] | Replacement Option One [Member]
Subsequent Event [Line Items]
Eligible options tendered for replacement option, value | $ / shares	2.1
Maximum [Member] | Replacement Option One [Member]
Subsequent Event [Line Items]
Eligible options tendered for replacement option, value | $ / shares	$ 11.85