0001558370-25-001853 | 10-K | XBRL Viewer

Stock-based compensation - 2019 Stock Option and Incentive Plan and 2023 Inducement Plan (Details) $ / shares in Units, $ in Millions			12 Months Ended
	Sep. 12, 2023 $ / shares shares	Aug. 07, 2023 USD ($) item installment $ / shares shares	Dec. 31, 2024 installment shares	Apr. 07, 2023 shares
Stock option exchange offer
Stock-based compensation
Vesting period (in years)		3 years
Number of quarterly installments for vesting \| installment		12
Eligible participants \| item		82
Exercise of stock options cancelled (in shares)		54,323
Percentage of options accepted for cancellation (in %)		86.60%
Issuance of common stock (in shares)	27,376
Exercise price per share (in $ per share) \| $ / shares	$ 10
Stock option exchange offer resulted in incremental stock-based compensation expense \| $		$ 0.1
Stock option exchange offer \| Minimum
Stock-based compensation
Exchange ratio		1.75
Exercise price (in $ per share) \| $ / shares		$ 69
Stock option exchange offer \| Maximum
Stock-based compensation
Exchange ratio		2.5
Exercise price (in $ per share) \| $ / shares		$ 140
2019 Stock Option and Incentive Plan
Stock-based compensation
Number stock option authorized (in shares)			1,202,548
Annual increase in cumulative number of shares authorized for issuance (in %)			4.00%
Vesting period (in years)			4 years
Number of common stock entitled for each option upon the exercise of the option			1
2019 Stock Option and Incentive Plan \| Non Executive Directors
Stock-based compensation
Vesting period (in years)			3 years
2019 Stock Option and Incentive Plan \| Vesting upon first anniversary
Stock-based compensation
Percentage of options vesting (in %)			25.00%
2019 Stock Option and Incentive Plan \| Vesting upon first anniversary \| Non Executive Directors
Stock-based compensation
Percentage of options vesting (in %)			33.00%
2019 Stock Option and Incentive Plan \| Vesting in equal quarterly installments
Stock-based compensation
Percentage of options vesting (in %)			75.00%
Number of quarterly installments for vesting \| installment			12
2019 Stock Option and Incentive Plan \| Vesting in equal quarterly installments \| Non Executive Directors
Stock-based compensation
Percentage of options vesting (in %)			67.00%
Number of quarterly installments for vesting \| installment			8
2023 Inducement Plan
Stock-based compensation
Stock reserved for future issuance (in shares)			10,000	50,000

Summary of significant accounting policies - Going concern (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Summary of significant accounting policies
Net loss	$ (43,503)	$ (81,580)	$ (64,915)
Accumulated deficit	$ (412,764)	$ (369,261)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details

- Definition

Amount of accumulated undistributed earnings (deficit).

+ References + Details

Reportable segments (Tables)

12 Months Ended

Dec. 31, 2024

Reportable segments

Summary of segment information for the company's single operating segment

The following represents segment information for the Company’s single operating segment, for the periods presented (in thousands):


	Year ended December 31,
	2024		2023		2022
Revenue	$	43,946	$	20,129	$	14,249
Add (deduct):
Direct research and development expense	$	(39,635)	$	(48,168)	$	(35,828)
Consulting and professional services expense		(11,728)		(10,088)		(11,464)
Personnel expenses, excluding stock-based compensation⁽¹⁾		(27,830)		(33,670)		(22,348)
Stock-based compensation		(2,014)		(2,345)		(5,043)
Depreciation and amortization expense⁽²⁾		(1,107)		(1,955)		(1,865)
Other segment items⁽³⁾		(8,940)		(10,091)		(3,332)
Interest income		3,701		5,293		1,633
Interest expense		(2)		(317)		(687)
Income tax benefit (expense)	$	106	$	(368)	$	(230)
Segment net loss	$	(43,503)	$	(81,580)	$	(64,915)

Adjustments and reconciling items	$	—	$	—	$	—
Consolidated net loss	$	(43,503)	$	(81,580)	$	(64,915)

⁽¹⁾ Personnel expenses include expenses for personnel, recruiting, training and travel

⁽²⁾ Depreciation and amortization expenses include depreciation for assets held for sale

⁽³⁾ Other segment items primarily include expenses for restructuring, impairment, other overhead, as well as foreign currency exchange gains and losses, and grant income

Restructuring

12 Months Ended

Dec. 31, 2024

Restructuring

Restructuring

4. Restructuring

On January 29, 2024, the Company announced and began implementing its decision to prioritize the clinical development of its eseba-vec (formerly HB-200) program for the treatment of HPV16+ head and neck cancers and its two Gilead-partnered infectious disease programs and to pause development activities related to HB-300 and most of its preclinical research activities. In connection with this strategic refocus, the Company’s board of directors approved a Restructuring Plan to rebalance the Company’s cost structure, which originally included a reduction of the Company’s workforce by approximately 30% and the discontinuation of the Company’s GMP manufacturing facility project. This original part of the Restructuring Plan was completed by the end of the second quarter of 2024 and the Company recorded restructuring charges of $1.3 million in the six months ended June 30, 2024.

During the third quarter of 2024, the Company started an enterprise-wide initiative intended to improve its business through specialized organizational programs that include targeted cost-savings and continued to take actions to implement further restructuring actions, which included a further reduction of the Company’s workforce by another approximately 20%. These continued restructuring actions are expected to be substantially completed by the end of the first quarter of 2025. The restructuring charges recorded for the continued restructuring actions for the three months ended September 30, 2024 were $0.9 million.

On November 18, 2024 the Company approved a plan to continue to improve its cost structure and operating efficiency, which includes a reduction in the Company’s workforce by approximately 80% of the Company’s then-current employee base and the closing and consolidation of office and laboratories in Vienna, Austria. The Company began the implementation of this restructuring plan in the fourth quarter of 2024 and expects these continued restructuring actions to be substantially completed by the end of the first half of 2025. The restructuring charges recorded for the continued restructuring actions for the three months ended December 31, 2024 were $0.5 million. This restructuring expenses relate primarily to disposal costs for the closing and consolidation of office and laboratories in Vienna, Austria, did not include social plan or severance payments and it is planned that the affected employees will continue to work throughout their termination period. In connection with the continued Restructuring Plan, in an effort to rebalance the Company’s cost structure in alignment with the Company’s strategic refocus and development of its oncology portfolio, the Company also announced that it will pause clinical development in its eseba-vec program, including an early termination of the Company’s ongoing Phase 1/2 clinical trial for the treatment of HPV16+ cancers. Going forward, the Company may implement further cost-saving initiatives that could result in additional restructuring charges including severance and other employee charges.

As a result of the restructuring plan and the enterprise-wide initiative, the Company incurred the following charges which were included within Restructuring expense in the consolidated statements of operations and comprehensive loss.

The following table summarizes the effect of the restructuring charges (in thousands):


	Year ended December 31,
	2024		2023		2022
Restructuring expense
Severance and other personnel expenses	$	2,067	$	—	$	—
Professional fees, disposal costs and other related charges	$	597	$	—	$	—
Total	$	2,664	$	—	$	—

The following table summarizes a roll-forward of cash restructuring-related liabilities, which are included within Accrued expenses and other current liabilities in the consolidated balance sheets (in thousands):



	Severance and other personnel costs		Disposal costs, professional fees and other related charges		Total
Balance as of December 31, 2023	$	—	$	—	$	—
Severance and other personnel costs, professional fees and other related charges		2,067		597		2,664
Total payments		(1,493)		(329)		(1,822)
Balance as of December 31, 2024	$	574	$	268	$	842

CONSOLIDATED BALANCE SHEETS (Parenthetical)	Dec. 31, 2024 $ / shares shares	Dec. 31, 2023 $ / shares shares
Preferred stock, par value (in dollars per share) \| $ / shares	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Series A convertible preferred stock
Preferred stock shares designated (in shares)	2,978	2,978
Preferred stock, shares outstanding (in shares)	370	370
Series A-1 convertible preferred stock
Preferred stock shares designated (in shares)	15,800	15,800
Preferred stock, shares outstanding (in shares)	10,800	10,800
Series A-2 convertible preferred stock
Preferred stock shares designated (in shares)	15,268	15,268
Preferred stock, shares outstanding (in shares)	15,268	15,268
Common stock
Common stock, par value (in dollars per share) \| $ / shares	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	40,000,000	20,000,000
Common stock, shares issued (in shares)	9,655,059	9,655,059
Common stock, shares outstanding (in shares)	9,655,022	9,655,022
Class A common stock
Common stock, par value (in dollars per share) \| $ / shares	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	3,900,000	3,900,000
Common stock, shares issued (in shares)	2,399,517	2,399,517
Common stock, shares outstanding (in shares)	2,399,517	2,399,517

CONSOLIDATED STATEMENTS OF CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY (DEFICIT) (Parenthetical) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) $ / shares	Dec. 31, 2022 USD ($) $ / shares
Series A-1 convertible preferred stock \| Public offering
Share price (in USD per share) \| $ / shares		$ 2,000
Issuance costs \| $		$ 1,975
Series A-2 convertible preferred stock \| Public offering
Share price (in USD per share) \| $ / shares	$ 1,310
Issuance costs \| $	$ 1,471
Common stock \| Public offering
Share price (in USD per share) \| $ / shares	$ 13.1	$ 20
Issuance costs \| $	$ 2,207	$ 2,713
Common stock \| Stock purchase agreement
Share price (in USD per share) \| $ / shares	$ 14.167	$ 30
Issuance costs \| $	$ 136	$ 0

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Dec. 31, 2024
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false
Rule 10b5-1 Arrangement Modified	false
Non-Rule 10b5-1 Arrangement Modified	false

Income taxes (Details) - USD ($) $ in Thousands	12 Months Ended
Income taxes (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Income taxes
Income tax benefits for the net operating losses incurred	$ 0	$ 0	$ 0
United States	(1,341)	1,710	(7,222)
Foreign (Austria)	(42,268)	(82,922)	(57,463)
Total income tax expense	$ (106)	$ 368	$ 230

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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-SubTopic 20
-Topic 740
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482659/740-20-45-2

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h))
-SubTopic 10
-Topic 235
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

+ Details

Loans payable

12 Months Ended

Dec. 31, 2024

Loans payable

Loans payable

11. Loans payable

As of December 31, 2024 and December 31, 2023, loans payable consisted of the following (in thousands):


	December 31,		December 31,
	2024		2023
Loans from FFG	$	—	$	1,172
Unamortized debt discount		—		(52)
Total loans payable, net	$	—	$	1,120

In connection with the funding agreements with the Austrian Research Promotion Agency, (Österreichische Forschungsförderungsgesellschaft, or “FFG”), the Company has received various loans (“FFG Loans”). The FFG Loans were made on a project-by-project basis.

The FFG Loans bear interest at rates that were below market rates of interest. The Company accounted for the imputed benefit arising from the difference between an estimated market rate of interest and the rate of interest charged by FFG as grant income from FFG. On the date that FFG loan proceeds are received, the Company recognized the portion of the loan proceeds allocated to grant funding as a discount to the carrying value of the loan and as unearned income, which was recognized as grant income over the term of the funding agreement.

The Company recognized no grant income during the year ended December 31, 2024, and grant income of $0.3 million and $0.6 million during the years ended December 31, 2023 and 2022, respectively, related to the recognition of the unearned income recorded for the imputed benefit of FFG Loans at below-market interest rates. No current unearned income related to the imputed benefit of FFG Loans at below-market interest rates as of December 31, 2024 and current unearned income of less than $0.1 million as of December 31, 2023.

In addition, the Company had recorded a discount to the carrying value of each FFG Loan for the portion of the loan proceeds allocated to grant funding, which was being amortized to interest expense over the term of the loan using the effective interest method. As of December 31, 2024 there was no unamortized debt discount related to FFG Loans and as of December 31, 2023, the unamortized debt discount related to FFG Loans was $0.1 million.

The Company recognized interest expense of less than $0.1 million, $0.3 million and $0.7 million during the years ended December 31, 2024, 2023 and 2022, respectively, related to the FFG Loans, which included interest expense

related to the amortization of debt discount of less than $0.1 million, $0.3 million and $0.7 million during the years ended December 31, 2024, 2023 and 2022, respectively. As of December 31, 2024, the Company has no outstanding loans payable. A final principal repayment of $1.1 million was made in the year ended December 31, 2024. A principal repayment of $1.8 million was made in the year ended December 31, 2023.

The Company used an estimated market rate of 20%, which was determined based on an average of the available interest rates on unsecured loans to comparable companies. A 10% increase or decrease in the estimated market rate of interest would have had no material impact on grant income or liabilities.

In the event that the underlying program research resulted in a scientific or technical failure, the principal then outstanding under any loan may be forgiven by FFG on a project-by-project basis. The FFG Loans contained no financial covenants and were not secured by any of the Company's assets.

Property, plant and equipment, net and assets held for sale (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Property, plant and equipment, net and assets held for sale
Property and equipment, gross	$ 6,065	$ 17,565
Less: Accumulated depreciation	(5,886)	(9,823)
Property and equipment, net	179	7,742
Depreciation expense	400	2,000	$ 1,900
Impairment charges of assets	4,004	12,766	$ 0
Carrying value		0
Land
Property, plant and equipment, net and assets held for sale
Property and equipment, gross		2,025
Impairment charges of assets	0
Leasehold improvements
Property, plant and equipment, net and assets held for sale
Property and equipment, gross	3,095	3,300
Construction in progress
Property, plant and equipment, net and assets held for sale
Property and equipment, gross	8	212
Laboratory equipment
Property, plant and equipment, net and assets held for sale
Property and equipment, gross		8,722
Impairment charges of assets	3,600
Furniture and fixtures
Property, plant and equipment, net and assets held for sale
Property and equipment, gross	601	654
Computer equipment and software
Property, plant and equipment, net and assets held for sale
Property and equipment, gross	$ 2,361	$ 2,652

Reportable segments (Details) - USD ($) $ in Thousands	12 Months Ended
Reportable segments (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Reportable segments
Revenue	$ 43,946	$ 20,129	$ 14,249
Direct research and development expense	(68,507)	(86,424)	(68,645)
Stock-based compensation	(2,014)	(2,345)	(5,043)
Depreciation and amortization expense	(2,753)	(3,552)	(3,602)
Interest income	3,701	5,293	1,633
Interest expense	(2)	(317)	(687)
Income tax expense	106	(368)	(230)
Net loss	(43,503)	(81,580)	(64,915)
Operating Segments \| Single operating segment
Reportable segments
Revenue	43,946	20,129	14,249
Direct research and development expense	(39,635)	(48,168)	(35,828)
Consulting and professional services expense	(11,728)	(10,088)	(11,464)
Personnel expenses, excluding stock-based compensation	(27,830)	(33,670)	(22,348)
Stock-based compensation	(2,014)	(2,345)	(5,043)
Depreciation and amortization expense	(1,107)	(1,955)	(1,865)
Other segment items	(8,940)	(10,091)	(3,332)
Interest income	3,701	5,293	1,633
Interest expense	(2)	(317)	(687)
Income tax expense	106	(368)	(230)
Net loss	$ (43,503)	$ (81,580)	$ (64,915)
Segment Reporting, Other Segment Item, Composition, Description	Other segment items primarily include expenses for restructuring, impairment, other overhead, as well as foreign currency exchange gains and losses, and grant income	Other segment items primarily include expenses for restructuring, impairment, other overhead, as well as foreign currency exchange gains and losses, and grant income	Other segment items primarily include expenses for restructuring, impairment, other overhead, as well as foreign currency exchange gains and losses, and grant income

Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Pay vs Performance Disclosure
Net Income (Loss)	$ (43,503)	$ (81,580)	$ (64,915)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details

Commitments and contingencies (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Commitments and contingencies
Non-cancellable obligations	$ 4.7
Licensing fees from intellectual property licenses	$ 3.6	$ 1.6	$ 1.0

Income taxes - Effective income tax reconciliation (Details)	12 Months Ended			24 Months Ended	36 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2023	Dec. 31, 2024
Operating Loss Carryforwards [Line Items]
U.S. federal statutory income tax rate	(21.00%)	(21.00%)	(21.00%)		(21.00%)
State income taxes, net of federal benefit		(0.30%)
Foreign tax rate differential	(2.00%)	(2.70%)	(4.00%)
Not taxable government grants	4.90%	6.80%	3.80%
Stock-based compensation	0.80%	0.60%	0.50%
Global intangible low-taxed income		2.30%	1.40%
Other	2.20%	0.20%	0.10%
Change in deferred tax asset valuation allowance	24.70%	28.20%	27.10%
Effective income tax rate	(0.20%)	0.50%	0.30%
Austria
Operating Loss Carryforwards [Line Items]
U.S. federal statutory income tax rate	(23.00%)	(24.00%)		(25.00%)

Summary of significant accounting policies - Reverse Stock Split (Details)	Jul. 09, 2024 $ / shares
Summary of significant accounting policies
Reverse stock split of common stock	0.1
Common stock, par value (in dollars per share)	$ 0.0001

Stock-based compensation - Stock option valuation assumptions (Details)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Assumptions used in the Black-Scholes option-pricing model
Risk-free interest rate	4.48%	3.70%	3.09%
Expected term (in years)	6 years 1 month 6 days	5 years 8 months 12 days	6 years
Expected volatility	101.70%	93.60%	85.40%

Leases - Minimum lease payments (Details) $ in Thousands	Dec. 31, 2024 USD ($)
Operating leases
2025	$ 558
2026	208
2027	73
2028	73
Total lease payments	912
Less: interest	37
Present value of lease liabilities	$ 875

Impairment - Non-cash impairment charges (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Asset write-offs	$ (4,004)	$ (12,766)	$ 0
Total non-cash impairment charges	(4,004)	$ (12,766)
Laboratory equipment
Property, Plant and Equipment [Line Items]
Asset write-offs	$ (3,600)

Leases (Details) - USD ($) $ in Thousands	12 Months Ended
Leases (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Leases
Restricted cash	$ 200
Non-current restricted cash	104	$ 425
Current restricted cash	$ 98
Reduction in term of contract (in years)	2 years 6 months
Minimum
Leases
Remaining lease term (in years)	1 year
Maximum
Leases
Remaining lease term (in years)	4 years 3 months 18 days

Summary of significant accounting policies

12 Months Ended

Dec. 31, 2024

Summary of significant accounting policies

Summary of significant accounting policies

2. Summary of significant accounting policies

Basis of presentation

The Company’s consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). The accompanying consolidated financial statements include the accounts of the Company and its wholly owned subsidiary. All intercompany accounts and transactions have been eliminated in consolidation.

Going concern

At each reporting period, in accordance with Accounting Standards Codification ("ASC") 205-40, Going Concern, the Company evaluates whether there are conditions or events that raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date that the financial statements are issued. The Company’s evaluation entails analyzing prospective operating budgets and forecasts for expectations of the Company’s cash needs and comparing those needs to the current cash and cash equivalent balances. The Company is required to make certain additional disclosures if it concludes substantial doubt exists and it is not alleviated by the Company’s plans or when its plans alleviate substantial doubt about the Company’s ability to continue as a going concern.

This evaluation initially does not take into consideration the potential mitigating effect of management’s plans that have not been fully implemented as of the date the consolidated financial statements are issued. When substantial doubt exists under this methodology, management evaluates whether the mitigating effect of its plans sufficiently alleviates substantial doubt about the Company’s ability to continue as a going concern. The mitigating effect of management’s plans, however, is only considered if both (1) it is probable that the plans will be effectively implemented within one year after the date that the consolidated financial statements are issued, and (2) it is probable that the plans,

when implemented, will mitigate the relevant conditions or events that raise substantial doubt about the entity’s ability to continue as a going concern within one year after the date that these consolidated financial statements are issued. In performing its analysis, management excluded certain elements of its operating plan that cannot be considered probable. Under ASC 205-40, the future receipt of potential funding from future partnerships, equity or debt issuances, the potential milestones from the Gilead Collaboration Agreement and potential reductions in force cannot be considered probable at this time because these plans are not entirely within the Company’s control and/or have not been approved by the Board of Directors as of the date of these consolidated financial statements.

Since inception, the Company’s activities have consisted primarily of performing research and development to advance its technologies. The Company is still in the development phase and has not been marketing its technologies to date. Through December 31, 2024, the Company has funded its operations with proceeds from sales of common stock, sales of convertible preferred stock, sales of redeemable convertible preferred stock, collaboration and licensing agreements, grants and borrowings under various agreements with foreign public funding agencies. Since inception, the Company has incurred recurring losses, including net losses of $43.5 million, $81.6 million and $64.9 million for the years ended December 31, 2024, 2023 and 2022, respectively. As of December 31, 2024, the Company had an accumulated deficit of $412.8 million. The Company expects to continue to generate operating losses in the foreseeable future. As of the filing date of this Annual Report on Form 10-K, the Company’s expectation to generate negative operating cash flows in the future and the need for additional funding to support its planned operations raise substantial doubt regarding the Company’s ability to continue as a going concern for a period of one year after the date that these consolidated financial statements are issued. Management's plans to alleviate the conditions that raise substantial doubt include reduced spending and the pursuit of additional capital. Management has concluded that the likelihood that its plan to successfully obtain sufficient funding, or adequately reduce expenditures, while reasonably possible, is less than probable. Accordingly, the Company has concluded that substantial doubt exists about the Company's ability to continue as a going concern for a period of at least 12 months from the date of issuance of these consolidated financial statements.

The accompanying consolidated financial statements have been prepared assuming that the Company will continue as a going concern, which contemplates the realization of assets and the settlement of liabilities and commitments in the normal course of business. The consolidated financial statements do not reflect any adjustments relating to the recoverability and classification of assets or the amounts and classification of liabilities that might result from the outcome of the uncertainties described above.

Reverse stock split

On July 9, 2024, the Company effected a reverse stock split of the outstanding shares of its common stock on a one-for-ten (1:10) basis (the “Reverse Stock Split”). The Reverse Stock Split became effective at 5:00 p.m. Eastern Time on July 9, 2024 (the “Effective Time”) via a certificate of amendment to the Company’s Certificate of Incorporation filed with the Secretary of State of the State of Delaware. At the Effective Time of the Reverse Stock Split, every 10 issued and outstanding shares of the Company’s common stock were automatically combined into one issued and outstanding share of common stock. The par value per share of the common stock remained unchanged at $0.0001. Fractional shares were not issued in connection with the Reverse Stock Split. Stockholders who were otherwise entitled to receive a fractional share received a proportional cash payment. The Reverse Stock Split affected all stockholders uniformly and did not alter any stockholder’s relative interest in the Company’s equity securities, except for any adjustments for fractional shares. As a result of the Reverse Stock Split, proportionate adjustments were made to the conversion ratio for the Company’s Class A Common Stock and the conversion prices of the Company’s Series A Convertible Preferred Stock, Series A-1 Convertible Preferred Stock and Series A-2 Convertible Preferred Stock. All share, per share and option numbers and exercise prices appearing in this Annual Report on Form 10-K and the financial statements have been adjusted to give effect to the Reverse Stock Split for all prior periods presented. However, the Company’s annual, other periodic, and current reports, and all other information and documents incorporated by reference into this Annual Report on Form 10-K that were filed prior to July 9, 2024, do not give effect to the Reverse Stock Split.

Use of estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue, income and expenses during the reporting periods. Significant estimates and assumptions reflected in these consolidated financial statements include, but are not limited to, the recognition of revenue and income, the accrual of research and development expenses and general and administrative expenses, the present value of lease right of use assets and corresponding liabilities, the valuation of stock-based awards, the valuation of current loans payable, the impairment of long-lived assets, the fair value of assets held for sale and going concern. The Company bases its estimates on historical experience, known trends and other market-specific or other relevant factors that it believes to be reasonable under the circumstances. On an ongoing basis, management evaluates its estimates as there are changes in circumstances, facts and experience.

As of the date of issuance of these consolidated financial statements, the Company is not aware of any specific event or circumstance that would require the Company to update estimates, judgments or revise the carrying value of any assets or liabilities. Actual results may differ from those estimates or assumptions.

Foreign currency and currency translation

The functional currency for the Company is the United States dollar and the functional currency for the Company's wholly owned foreign subsidiary, HOOKIPA Biotech GmbH, is the euro.

Assets and liabilities of HOOKIPA Biotech GmbH are translated into United States dollars at the exchange rate in effect on the balance sheet date. Income items and expenses are translated at the average exchange rate in effect during the period. Unrealized translation gains and losses are recorded as a cumulative translation adjustment, which is included in the Consolidated Statements of Convertible Preferred Stock and Stockholders' Equity as a component of Accumulated other comprehensive loss. Adjustments that arise from exchange rate changes on transactions denominated in a currency other than the local currency are included in other income and expenses, net in the consolidated statements of operations and comprehensive loss as incurred.

Concentrations of credit risk and of significant suppliers

Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash, cash equivalents and short-term bank deposits held with banks in excess of publicly insured limits. For the years ended December 31, 2024 and December 31, 2023 the net proceeds from the Company’s offerings have been deposited in interest-bearing bank accounts with two of the largest investment grade U.S. financial institutions and have been partially invested in money market funds. The money market funds, held in U.S. dollars, are primarily invested in U.S. and foreign short-term debt obligations. As of December 31, 2024 and December 31, 2023, the Company’s cash and cash equivalents included smaller amounts of cash balances held in accounts with regional European banks at the Company’s Austrian subsidiary, partially in euros. The Company does not believe that it is subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships.

The Company relies, and expects to continue to rely, on a small number of vendors to manufacture supplies and raw materials for its development programs. These programs could be adversely affected by a significant interruption in these manufacturing services or the availability of raw materials.

As of December 31, 2024 Gilead Sciences, Inc. (“Gilead”) accounted for the majority of the accounts receivable balance. As of December 31, 2023 Gilead and F. Hoffmann-La Roche Ltd. and Hoffmann-La Roche Inc. (together “Roche”) accounted for the majority of the accounts receivable balance. For the years ended December 31, 2024, December 31, 2023 and December 31, 2022 Gilead and Roche accounted for the majority of the

Company’s revenues. For the year ended December 31, 2024 Roche accounted for a large portion of the Company’s revenues as a result of a contract modification and the recognition of upfront and milestone payments previously recorded as deferred revenues. Other customers accounted for less than 10.0% of accounts receivable or net revenues. The Company monitors the financial performance of its customers so that it can appropriately respond to changes in their credit worthiness. To date, the Company has not experienced any significant losses with respect to collection of its accounts receivable.

Deferred offering costs

The Company capitalizes certain legal, professional accounting and other third-party fees that are directly associated with in-process equity financings as deferred offering costs until such financings are consummated. After consummation of an equity financing, these costs are recorded in stockholders’ equity as a reduction of the additional paid-in capital on a pro-rata basis generated as a result of the offering. Should the in-process equity financing be abandoned, the deferred offering costs will be expensed immediately as a charge to operating expenses in the consolidated statements of operations and comprehensive loss.

Fair value measurements

Certain assets and liabilities are carried at fair value under 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 and that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques.

The Company’s cash equivalents are carried at fair value, determined according to the fair value hierarchy described above (see Note 6).

Cash equivalents

The Company considers all highly liquid investments with maturities of three months or less at the date of purchase to be cash equivalents. As of December 31, 2024 and December 31, 2023 cash equivalents consisted of money market funds and short-term deposits. The Company classifies investments in money market funds within Level 1 of the fair value hierarchy as the prices are available from quoted prices in active markets.

Assets held for sale

The fair values of property, plant, and equipment held for sale is classified as Level 3 in the fair value hierarchy due to a mix of unobservable inputs utilized such as independent research in the market as well as actual quotes from market participants.

Property and equipment

Property and equipment are stated at cost less accumulated depreciation and amortization. Depreciation and amortization expense is recognized using the straight-line method over the estimated useful life of each asset as follows:


		Estimated useful life
Leasehold improvements		shorter of useful life or term of lease
Laboratory equipment		2 - 10 years
Furniture and fixtures		2 - 10 years
Computer equipment and software		2 - 4 years

Costs for capital assets not yet placed into service are capitalized as construction-in-progress and depreciated once placed into service. Expenditures for repairs and maintenance are charged to expense as incurred. When property and equipment is sold or otherwise disposed of, the cost and related accumulated depreciation are eliminated from the accounts and any resulting gain or loss is reflected in the consolidated statements of operations.

Leases

The determination whether an arrangement qualifies as a lease is made at contract inception. A lease qualifies as a finance lease if any of the following criteria are met at the inception of the lease: (i) there is a transfer of ownership of the leased asset to the Company by the end of the lease term, (ii) the Company holds an option to purchase the leased asset that it is reasonably certain to exercise, (iii) the lease term is for a major part of the remaining economic life of the leased asset, (iv) the present value of the sum of lease payments equals or exceeds substantially all of the fair value of the leased asset, or (v) the nature of the leased asset is specialized to the point that it is expected to provide the lessor no alternative use at the end of the lease term. All other leases are recorded as operating leases and are included in right of use (“ROU”) assets and lease liabilities in the consolidated balance sheets. For leases with an initial term of 12 months or less, the Company does not recognize a right of use asset or lease liability. These short-term leases are expensed on a straight-line basis over the lease term.

ROU assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent its obligation to make lease payments arising from the lease. ROU assets and lease liabilities are recognized at the commencement date of the lease based upon the present value of lease payments over the lease term. When determining the lease term, the Company includes options to extend or terminate the lease when it is reasonably certain that the option will be exercised. The Company uses the implicit rate when readily determinable and uses its incremental borrowing rate when the implicit rate is not readily determinable based upon the information available at the commencement date in determining the present value of the lease payments. The incremental borrowing rate is determined using a secured borrowing rate for the same currency and term as the associated lease. The lease payments used to determine ROU assets may include lease incentives, stated rent increases and escalation clauses linked to rates of inflation when determinable and are recognized as ROU asset on the consolidated balance sheet. In addition, certain of the Company’s arrangements contain lease and non-lease components. The Company generally separates lease payments from non-lease payments. Operating leases are reflected in operating lease assets, in current operating lease liabilities and non-current operating lease liabilities in the consolidated balance sheets. Finance leases are reflected in finance lease

assets, in accrued expenses and other current liabilities and in other non-current operating lease liabilities in the consolidated balance sheets. The ROU asset is tested for impairment in accordance with ASC 360.

Capitalized Software Development Cost

The Company capitalizes certain implementation costs for internal-use software incurred in a cloud computing agreement that is a service contract. Eligible costs associated with cloud computing arrangements, such as software business applications used in the normal course of business, are capitalized in accordance with ASC 350. These costs are recognized on a straight-line basis in the same line item in the statement of operations and comprehensive loss as the expense for fees for the associated cloud computing arrangement, over the term of the arrangement, plus reasonably certain renewals. Amortization expense of $0.1 million associated with the Company's cloud computing arrangements has been recognized during each of the fiscal years ended December 31, 2024, December 31, 2023 and December 31, 2022. The Company tests for impairment whenever events or changes in circumstances indicate that the carrying amount may not be recoverable. In the year ended December 31, 2024 the Company recognized an impairment loss of less than $0.1 million associated with the Company's cloud computing arrangements (see Note 7).

Impairment of long-lived assets

Long-lived assets, including operating and finance lease right of use assets, consist of property and equipment. Long-lived assets to be held and used are tested for recoverability whenever events or changes in business circumstances indicate that the carrying amount of the assets may not be fully recoverable. Factors that the Company considers in deciding when to perform an impairment review include significant underperformance of the business in relation to expectations, significant negative technological, scientific or economic trends and significant changes or planned changes in the use of the assets.

If an impairment review is performed to evaluate a long-lived asset group for recoverability, the Company compares forecasts of undiscounted cash flows expected to result from the use and eventual disposition of the long-lived asset group to its carrying value. An impairment loss would be recognized in loss from operations when estimated undiscounted future cash flows expected to result from the use of an asset group are less than its carrying amount. The impairment loss would be based on the excess of the carrying value of the impaired asset group over its fair value (see Note 5 and Note 7).

Restructuring

Costs and liabilities associated with restructuring activities are recognized when the actions are probable and estimable, which is when management approves the associated actions. Employee-related severance charges are recognized at the time of communication to employees (see Note 4).

Segment information

The Company manages its operations as a single segment at the consolidated level for the purposes of assessing performance and making operating decisions. The Company's singular focus is on developing pharmaceutical products to prevent and cure infectious diseases and cancer. The Chief Executive Officer is the chief operating decision maker, and regularly reviews the consolidated operating results to make decisions about the allocation of the Company's resources based on consolidated net loss that is reported on the consolidated statements of operations. The majority of the Company's tangible assets are held in Austria (see Note 19).

The measure of segment assets is reported on the consolidated balance sheet as total assets.

Revenue recognition from collaboration and licensing

The Company recognized revenue from collaboration and license agreements with Gilead and Roche.

Under the collaboration and license agreement with Gilead (as amended and restated, the “Gilead Collaboration Agreement”), the parties agreed to collaborate with respect to two preclinical research programs to evaluate potential vaccine products for the treatment, cure, diagnosis or prevention of the hepatitis B virus (“HBV”) and the human immunodeficiency virus (“HIV”). In February 2022, the parties signed an amended and restated collaboration agreement (the “Restated Gilead Collaboration Agreement”), which revised the terms only for the HIV program, whereby the Company took on development responsibilities for the HIV program candidate through a Phase 1b clinical trial. The Company’s performance obligations under the terms of the original agreement include one combined performance obligation for each research program (HBV and HIV) comprised of the transfer of intellectual property rights (licenses) and providing research and development services. The terms of the Restated Gilead Collaboration Agreement added an additional performance obligation to perform research and development work for the HIV program. The licenses do not represent distinct performance obligations, because they cannot be used without the research and development services. Payments to the Company under the Restated Gilead Collaboration Agreement include a non-refundable up-front payment, payments for research and development activities, payments based upon the achievement of defined milestones, and if certain future conditions are met, payments for manufacturing services, commercial milestones and royalties on product sales.

Under the research collaboration and license agreement with Roche (the “Roche Collaboration Agreement”), the Company agreed to conduct research and early clinical development through Phase 1b for HB-700, a novel investigational arenaviral immunotherapy for the treatment of KRAS-mutated cancers. The Roche Collaboration Agreement also included an obligation of the Company to deliver a specified package of preclinical data and results with respect to a second program, targeting undisclosed cancer antigens (collectively “UCAs”) and an option for Roche to license the UCA program. The Company’s performance obligations under the terms of the Roche Collaboration Agreement included one combined performance obligation for the transfer of intellectual property rights (licenses) and providing research and development services for the HB-700 program, and a second, separate performance obligation to perform research and development services with respect to the UCA program. The UCA Option provided a right to license the program at the standalone selling price and therefore did not constitute a separate performance obligation. Payments to the Company under the Roche Collaboration Agreement included a non-refundable up-front payment, payments based upon the achievement of defined milestones, an additional payment if the option for the UCA program was exercised and royalties on product sales. In January 2024, Roche provided written notice of the termination of the Roche Collaboration Agreement to the Company resulting in early recognition of revenue previously recorded as deferred revenue. The termination was made according to Roche’s right to terminate without cause, acknowledging that, the Company had met all go-forward criteria under the agreement. Upon the Roche Collaboration Agreement termination effective date of April 25, 2024, the Company regained full control of the associated intellectual property portfolio and has full collaboration and licensing rights for the HB-700 program.

The Company evaluates its collaboration and licensing arrangements pursuant to ASC 606 Revenue from Contracts with Customers. To determine the recognition of revenue from arrangements that fall within the scope of ASC 606, the Company performs the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the Company satisfies a performance obligation.

Under ASC 606, the Company applies significant judgement to evaluate whether the promises under the collaboration and licensing arrangements, represent separate or one or more combined performance obligations, the allocation of the transaction price to identified performance obligations, the timing of revenue recognition, whether the

UCA Option constitutes a material right, and the determination of when milestone payments are probable of being received.

Upfront payment and program initiation fee

The non-refundable upfront-payment received by the Company upon signing of the Gilead Collaboration Agreement, and milestone payments that were linked to future performance obligations, were initially recorded as deferred revenue and allocated between the two research program performance obligations. Such amounts are recognized as revenue over the performance period of the respective services on a percent of completion basis using total estimated research and development labor hours (input method) for each of the obligations. The percent of completion basis using labor hours was considered the best measure of progress in which control of the combined performance obligations transfers to the customer, due to the short time intervals in which research results are shared with the collaboration partner and the nature of the work being performed.

The non-refundable program initiation payment received from Gilead upon signing of the Restated Collaboration Agreement was also initially recorded as deferred revenue and is recognized on a percent of completion basis using total estimated research and development costs (input method) for the performance of the obligations. The percent of completion basis using research and development costs was considered the best measure of progress in which control of the performance obligations transfers to the customer, due to the immediate benefit that it adds to the value of the customer’s rights on the program, the short time intervals in which development results are shared and the nature of the work being performed.

The non-refundable upfront-payment received by the Company upon signing of the Roche Collaboration Agreement was initially recorded as deferred revenue and allocated between the HB-700 program and the UCA program. Such amounts were recognized as revenue over the performance period of the respective services on a percent of completion basis using total estimated research and development costs (input method) for each of the obligations during the initial term of the contract. The percent of completion basis using research and development costs was considered the best measure of progress in which control of the performance obligations transfers to the customer.

Reimbursement for services

Under the Gilead Collaboration Agreement and historically under the Roche Collaboration Agreement prior to termination, the Company incurs employee expenses as well as external costs for research, manufacturing and clinical trial activities presented as operating expenses or prepaid expenses. Based on the nature of the Company's responsibilities under the collaboration arrangements, reimbursement of those costs are presented as revenue and not deducted from expenses, as the Company controls the research activities. Amounts of consideration allocated to the performance of research or manufacturing services are recognized over the period in which services are performed. Reimbursements for external costs are recognized as revenues as progress is achieved. Unpaid reimbursement amounts are presented as Accounts Receivable.

Research and development milestones

The Gilead Collaboration Agreement includes, and the Roche Collaboration Agreement included, contingent milestone payments related to specified preclinical and clinical development milestones. These milestone payments represent variable consideration that are not initially recognized within the transaction price as they are fully constrained under the guidance in ASC 606, due to the scientific uncertainties and the required commitment from Gilead and Roche. While no further milestone payments are expected under the terminated Roche Collaboration Agreement, the Company will continue to assess the probability of significant reversals for any amounts that become likely to be realized under the Gilead Collaboration Agreement prior to including the variable consideration associated with these payments within the transaction price.

Sales-based milestones and royalty payments

The Gilead Collaboration Agreement also includes, and the Roche Collaboration Agreement included, certain sales-based milestone and royalty payments upon successful commercialization of a licensed product. In accordance with ASC 606-10-55-65 Sales Based or Usage Based Royalties, the Company recognizes revenues from sales-based milestone and royalty payments at the later of (i) the occurrence of the subsequent sale; or (ii) the performance obligation to which some or all of the sales-based milestone or royalty payments has been allocated has been satisfied. The Company anticipates recognizing these milestones and royalty payments if and when subsequent sales are generated from a licensed product by the collaboration partner.

Cost to fulfill contracts

The Company incurs costs for personnel, supplies and other costs related to its laboratory operations as well as fees from third parties and license expenses in connection with its research and development obligations under the collaboration and licensing agreements. These costs are recognized as research and development expenses over the period in which services are performed. Sublicense fees triggered by the receipt of payments are capitalized as an asset when the obligation to pay the fee arises. The capitalized asset is amortized over the period in which the revenue from the triggering payment is recognized.

Research and development costs

Research and development costs are expensed as incurred. Research and development expenses consist of costs incurred in performing research and development activities, including salaries and bonuses, stock-based compensation, employee benefits, facilities costs, laboratory supplies, depreciation, manufacturing expenses and external costs of vendors engaged to conduct preclinical development activities and clinical trials as well as the cost of licensing technology. Advance payments for goods or services to be received in the future for use in research and development activities are recorded as prepaid expenses. The prepaid amounts are expensed as the related goods are delivered or the services are performed.

Upfront payments, milestone payments and annual payments made for the licensing of technology are generally expensed as research and development in the period in which they are incurred. Incremental sublicense fees triggered by contracts with customers are capitalized and expensed as research and development expenses over the period in which the related revenue is recognized.

Research and manufacturing contract costs and accruals

The Company has entered into various research and development and manufacturing contracts. Related payments are recorded as the corresponding expenses are incurred. The Company records accruals for estimated ongoing costs and prepaid expenses for advance payments. When evaluating the adequacy of the accrued liabilities and prepaid expenses, the Company analyzes progress of the research studies or clinical trials and manufacturing activities, including the phase or completion of events, invoices received and contracted costs. Significant judgments and estimates are made in determining the accrued balances at the end of any reporting period. Actual results could differ from the Company's estimates. The Company's historical accrual estimates have not been materially different from the actual costs.

Government grant agreements and research incentives

The Company recognizes funding from grants and research incentives received from Austrian government agencies as well as from New York State and New York City government agencies in the United States as other income. Income from grants and incentives is recognized in the period during which the related qualifying expenses are incurred, provided that the conditions under which the grants or incentives were provided have been met. For grants under funding

agreements and for proceeds under research incentive programs, the Company recognizes grant and incentive income in an amount equal to the estimated qualifying expenses incurred in each period multiplied by the applicable reimbursement percentage.

Grant funding that has been received by the Company in advance of incurring qualifying expenses is recorded as deferred income. Grant and incentive income recognized upon incurring qualifying expenses in advance of receipt of grant funding or proceeds from research and development incentives is recorded in the consolidated balance sheets as prepaid expenses and other current assets.

The Company has received loans under funding agreements that bear interest at rates that are below market rates of interest. The Company accounts for the imputed benefit arising from the difference between a market rate of interest and the rate of interest charged as additional grant funding, and records interest expense for the loans at a market rate of interest. On the date that loan proceeds are received, the Company recognizes the portion of the loan proceeds allocated to grant funding as a discount to the carrying value of the loan and as other liability, which is subsequently recognized as additional grant income over the term of the funding agreement.

Stock-based compensation

The Company measures stock-based awards granted to employees and directors based on the fair value on the date of grant using the Black-Scholes option-pricing model for options or the difference between the purchase price per share of the award, if any, and the fair value of the Company's common stock for restricted common stock awards. Compensation expense for those awards is recognized over the requisite service period, which is generally the vesting period of the respective award. The Company uses the graded-vesting method to record the expense of awards with service-based vesting conditions.

The Company classifies stock-based compensation expense in its consolidated statements of operations and comprehensive loss in the same manner in which the recipient's payroll costs are classified or in which the recipient's service payments are classified.

Comprehensive loss

Comprehensive loss includes net loss and foreign currency translation adjustments. For the year ended December 31, 2024, $2.8 million of foreign currency gain adjustments. For the years ended December 31, 2023 and December 31, 2022, comprehensive loss included $0.8 million and $2.4 million, respectively, of foreign currency translation loss adjustments.

Net loss per share

Basic net loss per share is computed by dividing the net loss by the weighted average number of shares of common stock outstanding for the period. Diluted net loss per share is computed by dividing net loss by the weighted average number of shares outstanding for the period, including potential dilutive shares assuming the dilutive effect of outstanding stock options and of convertible preferred stock. For periods in which the Company has reported net losses, diluted net loss per common share is the same as basic net loss per share, since dilutive common shares are not assumed to have been issued if their affect is anti-dilutive.

The Company reported a net loss attributable to common stockholders for the years ended December 31, 2024, 2023 and 2022.

Income taxes

The Company accounts for income taxes under the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the consolidated financial statements or in the Company's tax returns. Under this method, deferred tax assets and liabilities are determined on the basis of the differences between the financial statement and tax bases of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period that includes the enactment date. Changes in deferred tax assets and liabilities are recorded in income tax expense. 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 through a charge to income tax expense. Potential for recovery of deferred tax assets is evaluated by estimating the future taxable profits expected and considering prudent and feasible tax planning strategies.

The Company accounts for uncertainty in income taxes recognized in the consolidated financial statements by applying a two-step process to determine the amount of tax benefit to be recognized. First, the tax position must be evaluated to determine the likelihood that it will be sustained upon external examination by the taxing authorities. If the tax position is deemed more-likely-than-not to be sustained, the tax position is then assessed to determine the amount of benefit to recognize in the financial statements. The amount of the benefit that may be recognized is the largest amount that has a greater than 50% likelihood of being realized upon ultimate settlement. 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 net interest and penalties.

The 2017 Tax Cuts and Jobs Act subjects a US shareholder to tax on global intangible low-taxed income (“GILTI”) earned by certain foreign subsidiaries. The FASB Staff Q&A, Topic 740, No. 5, Accounting for Global Intangible Low-Taxed Income, states that an entity can make an accounting policy election to either recognize deferred taxes for temporary basis differences expected to reverse as GILTI in the future years or provide for tax expense related to GILTI in the year the tax is incurred. The Company has elected to recognize tax expense related to GILTI in the year the tax is incurred.

Recent accounting pronouncements

From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board (“FASB”) or other standard setting bodies that the Company adopts as of the specified effective date.

Adopted as of current period

In November 2023, the FASB issued ASU No. 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures which requires public entities to disclose significant segment expenses regularly provided to the chief operating decision-maker. Public entities with a single reporting segment have to provide all disclosures required by ASC 280, including the significant segment expense disclosures. For public business entities, the guidance is effective for annual periods beginning after December 15, 2024. The Company adopted this standard with no impact to its consolidated financial statements.

Recently Issued Accounting Pronouncements

In November 2024, the FASB issued ASU 2024-03, Disaggregation of Income Statement Expenses, requiring entities to provide more information about an entity’s expenses. The new guidance requires disclosures about specific types of expenses included in the expense captions presented on the face of the income statement as well as disclosures

about selling expenses. The guidance is first effective for calendar year-end public business entities in their 2027 annual financial statements and 2028 interim financial statements. Companies can adopt the guidance on either a prospective or retrospective basis. The Company is currently evaluating the impact of the adoption of ASU 2024-03 on the consolidated financial statements and disclosures.

In November 2024, the FASB issued ASU 2024-04, Induced Conversions of Convertible Debt Instruments. The new guidance clarifies the assessment of whether a transaction should be accounted for as an induced conversion or extinguishment of convertible debt when changes are made to conversion features as part of an offer to settle the instrument. The guidance is effective for fiscal years beginning after December 15, 2025, with early adoption permitted, and it can be adopted either on a prospective or retrospective basis. The Company is currently evaluating the impact of the adoption of ASU 2024-04 on the consolidated financial statements and disclosures, but does not expect this ASU to have an impact on the consolidated financial statements and disclosures.

In December 2023, the FASB issued final guidance in ASU No. 2023-09, Income Taxes (ASC 740): Improvements to Income Tax Disclosures requiring entities to provide additional information in the rate reconciliation and disclosures about income taxes paid. For public business entities, the guidance is effective for annual periods beginning after December 15, 2024. The Company does not expect this ASU to have a material impact on the consolidated financial statements and disclosures.

Leases - Weighted average remaining lease term and weighted average discount rate (Details)	Dec. 31, 2024	Dec. 31, 2023
Leases
Operating lease, Weighted average remaining lease term (in years)	2 years	3 years 8 months 12 days
Operating lease, Weighted average discount rate	4.80%	4.10%

Common stock, Class A common stock and convertible preferred stock

12 Months Ended

Dec. 31, 2024

Common stock, Class A common stock and convertible preferred stock

Common stock, Class A common stock and convertible preferred stock

12. Common stock, Class A common stock and convertible preferred stock

The Company’s capital structure consists of common stock, Class A common stock and preferred stock. On July 9, 2024, the Company effected a reverse stock split of the outstanding shares of its common stock on a one-for-ten basis (see Note 2). As of December 31, 2024, the Company was authorized to issue 40,000,000 shares of common stock, 3,900,000 shares of Class A common stock and 10,000,000 shares of preferred stock. The Company has designated 2,978 of the 10,000,000 authorized shares of preferred stock as non-voting Series A convertible preferred stock, 15,800 of the 10,000,000 authorized shares of preferred stock as non-voting Series A-1 convertible preferred stock and 15,268 of the 10,000,000 authorized shares of preferred stock as non-voting Series A-2 convertible preferred stock. As of December 31, 2024, the Company had 9,655,022 shares of common stock, 2,399,517 shares of Class A common stock, 370 shares of Series A convertible preferred stock, 10,800 shares of Series A-1 convertible preferred stock and 15,268 shares of Series A-2 convertible preferred stock outstanding and issued. As a result of the Reverse Stock Split, 37 shares of common stock were retired due to round-down effects and redeemed in cash.

On June 5, 2023, the Company closed a public offering of 2,290,077 (22,900,768 before the Reverse Stock Split) shares of its common stock and 15,268 shares of Series A-2 convertible preferred stock at a public offering price of $13.10 and $1,310.00 per share, respectively, for net proceeds of $46.2 million after deducting underwriting discounts and commissions and offering expenses.

On February 15, 2022, the Company entered into a stock purchase agreement with Gilead (“Stock Purchase Agreement”), that requires Gilead, at the Company’s option, to purchase up to $35.0 million of the Company’s common stock. On February 15, 2022, Gilead purchased an initial amount of 166,666 (1,666,666 before the Reverse Stock Split) shares of the Company’s common stock in exchange for $5.0 million in cash at a purchase price per share equal to $30.00. On December 20, 2023, the parties amended and restated the Stock Purchase Agreement (the “Amended Stock Purchase Agreement”) and Gilead purchased 1,500,000 (15,000,000 before the Reverse Stock Split) shares of the Company’s common stock in exchange for approximately $21.25 million in cash at a purchase price per share equal to $14.167. Pursuant to the terms of the Amended Stock Purchase Agreement, the Company may require Gilead to purchase the balance of the $8.75 million of common stock as participation in potential future equity raises. The Company’s right to sell shares of its common stock to Gilead is subject to specified limitations, including a limitation that prevents the Company from requesting purchases of shares of common stock by Gilead that would result in a beneficial ownership of more than 19.9% of the total number of outstanding shares of common stock by Gilead.

The Company has three series of preferred stock authorized, issued and outstanding as of December 31, 2024: Series A convertible preferred stock, Series A-1 convertible preferred stock, and Series A-2 convertible preferred stock. Shares of Series A, Series A-1 and Series A-2 convertible preferred stock may be independently converted into common stock. Holders of Series A, Series A-1 and Series A-2 convertible preferred stock have equal rights, powers and privileges.

Holders of common stock are entitled to one vote for each share held on all matters submitted to a vote of the stockholders. The holders of Class A common stock and Series A, Series A-1 and Series A-2 convertible preferred stock are not entitled to vote, except as required by law. The holders of common stock and Class A common stock do not have any cumulative voting rights.

Each holder of Class A common stock has the right to convert each share of Class A common stock into ten shares of common stock at such holder's election. Each holder of Series A, Series A-1 and Series A-2 convertible preferred stock has the right to convert each share of Series A, Series A-1 and Series A-2 convertible preferred stock into 100 shares of common stock at any time at the holder’s option, provided that the holder will be prohibited, subject to certain exceptions, from converting Series A, Series A-1 and Series A-2 convertible preferred stock into shares of the Company’s common stock if, as a result of such conversion, the holder, together with its affiliates, would own more than 9.99% of the total number of shares of the Company’s common stock then issued and outstanding.

Holders of common stock and Class A common stock are entitled to receive ratably any dividends declared by the board of directors out of funds legally available for that purpose, subject to any preferential dividend rights of any outstanding preferred stock. Holders of Series A. Series A-1 and Series A-2 preferred stock will be entitled to receive dividends at a rate equal to (on an as-if-converted-to-common stock basis), and in the same form and manner as, dividends actually paid on shares of the Company’s common stock. Holders of common stock and Class A common stock have no preemptive rights, conversion rights, or other subscription rights or redemption or sinking fund provisions.

In the event of a liquidation, dissolution, or winding up of the Company, holders of the Company’s Series A, Series A-1 and Series A-2 convertible preferred stock will receive a payment equal to $0.001 per share of Series A, Series A-1 and Series A-2 convertible preferred stock before any proceeds are distributed to the holders of common stock. Then, holders of common stock and Class A common stock will be entitled to share ratably in all assets remaining after payment of all debts and other liabilities.

There were 370 shares of Series A convertible preferred stock, 10,800 shares of Series A-1 convertible preferred stock and 15,268 shares of Series A-2 convertible preferred stock outstanding as of December 31, 2024 and December 31, 2023, respectively. In May 2023 certain of the Company’s stockholders elected to convert an aggregate of 1,327 shares of Series A convertible preferred stock and an aggregate of 5,000 shares of Series A-1 convertible preferred stock owned by such holders into an aggregate of 632,700 (6,327,000 before the Reverse Stock Split) shares of the Company’s common stock.

- Definition

The entire disclosure for equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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-Paragraph 1
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Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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Reference 15: http://www.xbrl.org/2003/role/disclosureRef
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Reference 19: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

CONSOLIDATED STATEMENTS OF CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY (DEFICIT) - USD ($) $ in Thousands	Convertible Preferred Stock Series A convertible preferred stock	Convertible Preferred Stock Series A-1 convertible preferred stock	Convertible Preferred Stock Series A-2 convertible preferred stock	Convertible Preferred Stock	Common Stock Common stock Public offering	Common Stock Common stock Stock purchase agreement	Common Stock Common stock	Common Stock Class A common stock	Common Stock Series A convertible preferred stock	Common Stock Series A-1 convertible preferred stock	Additional Paid-In Capital Series A convertible preferred stock	Additional Paid-In Capital Series A-1 convertible preferred stock	Additional Paid-In Capital Series A-2 convertible preferred stock	Additional Paid-In Capital Public offering	Additional Paid-In Capital Stock purchase agreement	Additional Paid-In Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit	Series A-1 convertible preferred stock	Series A-2 convertible preferred stock	Public offering	Stock purchase agreement	Total
Balance at the beginning of the period at Dec. 31, 2021				$ 0			$ 0	$ 0								$ 317,138	$ (4,780)	$ (222,766)					$ 89,592
Balance at the beginning of the period (in shares) at Dec. 31, 2021				1,697			2,738,348	3,819,732
Increase (Decrease) in Stockholders' Equity
Conversion of Class A common stock to common stock							$ 0	$ 0
Conversion of Class A common stock to common stock (in shares)							142,022	(1,420,215)
Issuance of stock		$ 0			$ 0	$ 0						$ 29,625		$ 40,687	$ 5,000				$ 29,625		$ 40,687	$ 5,000
Issuance of stock (in shares)		15,800			2,170,000	166,666
Issuance of common stock upon exercise of stock options							$ 0									3							3
Issuance of common stock upon exercise of stock options (in shares)							3,422
Vesting of restricted stock							$ 0									0
Vesting of equity grants (in shares)							11,255
ATM costs																(142)							(142)
Foreign currency translation adjustment, net of tax																	(2,376)						(2,376)
Stock-based compensation income																5,043							5,043
Net loss																		(64,915)					(64,915)
Balance at the end of the period at Dec. 31, 2022				$ 0			$ 1	$ 0								397,353	(7,156)	(287,681)					102,517
Balance at the end of the period (in shares) at Dec. 31, 2022				17,497			5,231,713	2,399,517
Increase (Decrease) in Stockholders' Equity
Conversion of Class A common stock to common stock	$ 0	$ 0							$ 0	$ 0	$ 0	$ 0
Conversion of Class A common stock to common stock (in shares)	(1,327)	(5,000)							132,700	500,000
Issuance of stock			$ 0		$ 0	$ 0							$ 18,530	$ 27,793	$ 21,114					$ 18,530	$ 27,793	$ 21,114
Issuance of stock (in shares)			15,268		2,290,077	1,500,000
Issuance of common stock upon exercise of stock options							$ 0									1							1
Issuance of common stock upon exercise of stock options (in shares)							569
ATM costs																(86)							(86)
Foreign currency translation adjustment, net of tax																	(777)						(777)
Stock-based compensation income																2,345							2,345
Net loss																		(81,580)					(81,580)
Balance at the end of the period at Dec. 31, 2023				$ 0			$ 1	$ 0								467,050	(7,933)	(369,261)					$ 89,857
Balance at the end of the period (in shares) at Dec. 31, 2023				26,438			9,655,059	2,399,517
Increase (Decrease) in Stockholders' Equity
Issuance of common stock upon exercise of stock options (in shares)																							0
Fractional shares retired as a result of reverse split							$ 0									0							$ 0
Fractional shares retired as a result of reverse split (in shares)							(37)
Foreign currency translation adjustment, net of tax																	2,846						2,846
Stock-based compensation income																2,014							2,014
Net loss																		(43,503)					(43,503)
Balance at the end of the period at Dec. 31, 2024				$ 0			$ 1	$ 0								$ 469,064	$ (5,087)	$ (412,764)					$ 51,214
Balance at the end of the period (in shares) at Dec. 31, 2024				26,438			9,655,022	2,399,517

401(k) Savings Plan (Details) - USD ($) $ in Millions	12 Months Ended
401(k) Savings Plan (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Defined Contribution Plan Disclosure [Line Items]
Expenses recognized for the 401(k) Plan	$ 0.4	$ 0.6	$ 0.6
Maximum
Defined Contribution Plan Disclosure [Line Items]
Matching contribution to defined contribution savings plan	100.00%
Employer's Matching contribution to defined contribution savings plan	4.00%

401(k) Savings Plan

12 Months Ended

Dec. 31, 2024

401(k) Savings Plan

401(k) Savings Plan

16. 401(k) Savings Plan

The Company established a defined contribution savings plan under Section 401(k) of the Internal Revenue Code. This plan provides that eligible employees can elect to contribute to the 401(k) Plan, subject to certain limitations, on a pretax basis. The Company matches up to 100% of the first 4% of each employee’s contribution. During the years ended December 31, 2024, December 31, 2023 and December 31, 2022 expenses recognized for the 401(k) Plan were $0.4 million, $0.6 million and $0.6 million, respectively.

- Definition

The entire disclosure for retirement benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 70
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480794/715-70-50-1

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480482/715-20-55-17

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(iv)(03)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (q)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (l)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/715/tableOfContent

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(iii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (o)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (p)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (r)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (r)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480126/715-20-S99-2

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 60
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480266/715-60-50-3

+ Details

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (Parenthetical)	Jul. 09, 2024
CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS
Reverse stock split of common stock	0.1

Receivable research incentive

12 Months Ended

Dec. 31, 2024

Receivable research incentive

Receivable research incentive

8. Receivable research incentive

The Company participates in a research incentive program provided by the Austrian government under which it is entitled to reimbursement of a percentage of qualifying research and development expenses and capital expenditures incurred in Austria. Submissions for reimbursement under the program are submitted annually. Incentive amounts are generally paid out during the calendar year that follows the year of the expenses but remain subject to subsequent examinations by the responsible authority. Reimbursements received in excess of the recognized receivable research incentive for a certain period are recorded within other long term liabilities for potential repayment until such time that an audit has taken place, upon expiration of the potential reclaim period, or when it is no longer probable that a reclaim will happen. The years 2018 to present remain open to examination by the authorities.

Furthermore, the Company participated in the life sciences research and development program provided by the New York State government under which it was entitled to reimbursement of a percentage of qualifying research and development expenses in New York State up to $0.5 million per year for the years 2019 to 2021. Incentive amounts are generally paid out six to nine months after amended tax returns including a certificate of tax credit issued by Empire State Development are filed.

The Company also participates in the New York City biotechnology tax credit program, according to which certain expenses for business in the biotechnology field in New York City limited to $0.25 million per year for three consecutive years from January 1, 2023 to December 31, 2025 are incentivized. The biotechnology tax credit can be refunded or applied against the next year's tax if it exceeds the current year's tax liability. A submission for reimbursement under the program for the year 2024 was submitted in January of 2025, and no receivable was recognized in the year ended December 31, 2024.

As of December 31, 2024, the Company recognized receivables of $23.4 million from the research incentive programs, which are reported in receivable research incentive in the Company’s consolidated balance sheet. $23.2 million relate to the Austrian research incentive program, $0.1 million relate to the New York State life sciences research and development program and $0.1 million relate to the New York City biotechnology tax credit program. In February 2025, the Company received the payment related to the $17.3 million receivable from Austrian research incentive program for the years 2022 and 2023. As of December 31, 2023, the Company recognized receivables of $18.8 million from the research incentive programs with $17.3 million related to the Austrian research incentive program, $1.4 million relate to the New York State life sciences research and development program and $0.1 million relate to the New York City biotechnology tax credit program.

During the years ended December 31, 2024, 2023 and 2022, the Company recorded $7.4 million, $10.9 million and $7.3 million, respectively, of income related to the incentive programs within the Company’s consolidated statements of operations and comprehensive loss as part of the grant income. Income for the year ended December 31, 2024 relate to the Austrian incentive program. Income for the year ended December 31, 2023 included $9.4 million related to the Austrian research incentive program, $1.4 million related to the New York State life sciences research and development program and $0.1 million related to the New York City biotechnology tax credit program. Income for the year ended December 31, 2022 related to the Austrian research incentive program. Research incentives depend on the eligible research and development expenses of the respective period.

Property, plant and equipment, net and assets held for sale - Schedule of classified as held for sale (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2024 USD ($)
Property, plant and equipment, net and assets held for sale
Balance as of ending	$ 2,216
Land
Property, plant and equipment, net and assets held for sale
Additions to Assets Held for Sale	1,895
Balance as of ending	1,895
Laboratory equipment
Property, plant and equipment, net and assets held for sale
Additions to Assets Held for Sale	321
Balance as of ending	$ 321

Accrued expenses and other current liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Accrued expenses and other current liabilities
Salaries and bonuses	$ 4,193	$ 5,665
Social security contributions	259	340
Unearned grant income		52
Accrued external research and development expenses	1,845	4,594
Accrued external general and administration expenses	2,921	292
Accrued for property and equipment acquisitions		14
Accrued for restructuring expenses	842
Income taxes		367
Other accruals and liabilities.	592	777
Total	$ 10,652	$ 12,101

Income taxes (Tables)

12 Months Ended

Dec. 31, 2024

Income taxes

Schedule of losses before income taxes

For financial reporting purposes, losses before income taxes for the years ended December 31, 2024, 2023 and 2022 consisted of the following (in thousands):


	Year ended December 31,
	2024		2023		2022
United States	$	(1,341)	$	1,710	$	(7,222)
Foreign (Austria)		(42,268)		(82,922)		(57,463)
Net loss before tax	$	(43,609)	$	(81,212)	$	(64,685)

Schedule of components of the consolidated income tax provision


	Year ended December 31,
	2024		2023		2022
United States	$	(1,341)	$	1,710	$	(7,222)
Foreign (Austria)		(42,268)		(82,922)		(57,463)
Net loss before tax	$	(43,609)	$	(81,212)	$	(64,685)

Schedule of effective income tax rate reconciliation


	Year ended December 31,
	2024			2023			2022
U.S. federal statutory income tax rate		(21.0)	%		(21.0)	%		(21.0)	%
State income taxes, net of federal benefit		—			(0.3)			—
Foreign tax rate differential⁽¹⁾		(2.0)			(2.7)			(4.0)
Not taxable government grants⁽²⁾		(4.9)			(6.8)			(3.8)
Stock-based compensation		0.8			0.6			0.5
Global intangible low-taxed income		—			2.3			1.4
Other		2.2			0.2			0.1
Change in deferred tax asset valuation allowance⁽³⁾		24.7			28.2			27.1
Effective income tax rate		(0.2)	%		0.5	%		0.3	%

⁽¹⁾ The 2.0% increase for the year ended December 31, 2024, the 2.7% increase for the year ended December 31, 2023, and the 4.0% increase for the year ended December 31, 2022, resulted from tax rate differences between U.S. and non-U.S. jurisdictions. Net loss before tax was principally generated in Austria, where the statutory tax rate is 23% for the year ended December 31, 2024, 24% for the year ended December 31, 2023 and 25% for the year ended December 31, 2022.

⁽²⁾For the years ended December 31, 2024, 2023 and 2022, 4.9%, 6.8% and 3.8% increase, respectively, resulted from non-taxable research subsidies received from Austrian government agencies.

⁽³⁾For the years ended December 31, 2024, 2023 and 2022, 24.7% reduction, 28.2% reduction and 27.1% reduction, respectively, resulted from changes in valuation allowance on deferred tax assets. Deferred tax assets will only be recovered when the generation of future taxable income is more likely than not. Due to the nature of the Company's research activities and the inherent uncertainties the deferred tax assets are fully offset by a valuation allowance.

Schedule of components of the net deferred tax assets or liabilities

Components of the net deferred tax assets or liabilities as of the years ended December 31, 2024 and 2023 consisted of the following (in thousands):


	Year ended December 31,
	2024		2023
Deferred tax assets:
Net operating loss carryforwards	$	94,272	$	87,445
Capitalized R&D expenses		(0)		2,657
Credit carryforwards		1,787		1,265
Accrued expenses and other		182		317
Stock-based compensation		1,426		1,421
Operating lease liabilities		203		1,254
Total deferred tax assets		97,870		94,359
Valuation allowance		(93,382)		(89,309)
Total deferred tax assets		4,488		5,050

Deferred tax liabilities:
Accrued expenses and other		(4,281)		(3,774)
Fixed assets		(2)		(14)
Operating lease right of use asset		(205)		(1,262)
Total deferred tax liabilities		(4,488)		(5,050)

Net deferred tax assets	$	—	$	—

Schedule of changes in the valuation allowance for deferred tax assets

Changes in the valuation allowance for deferred tax assets during the years ended December 31, 2024, 2023 and 2022 related primarily to the increases in net operating loss carryforwards as follows (in thousands):


	Year ended December 31,
	2024		2023		2022
Valuation allowance at beginning of period	$	(89,309)	$	(65,774)	$	(53,728)
Increases		(4,073)		(23,535)		(12,046)
Valuation allowance at end of period	$	(93,382)	$	(89,309)	$	(65,774)

Common stock, Class A common stock and convertible preferred stock (Details) $ / shares in Units, $ in Thousands					1 Months Ended	12 Months Ended
	Jul. 09, 2024	Dec. 20, 2023 USD ($) $ / shares shares	Jun. 05, 2023 USD ($) $ / shares shares	Feb. 15, 2022 USD ($) $ / shares shares	May 31, 2023 shares	Dec. 31, 2024 item $ / shares shares	Dec. 31, 2023 USD ($) Vote $ / shares shares	Dec. 31, 2022 USD ($) $ / shares
Reverse stock split of common stock	0.1
Preferred stock, shares authorized (in shares)						10,000,000	10,000,000
Shares retired due to round-down effects and redeemed (in shares)						37
Net proceeds from public offering \| $			$ 46,200
Proceeds from issuance of common stock, net of issuance costs \| $							$ 49,043	$ 45,691
Number of series of preferred stock authorized, issued and outstanding \| item						3
Stock Purchase Agreement
Issuance of stock (in shares)				166,666
Share price (in USD per share) \| $ / shares				$ 30
Net proceeds from public offering \| $				$ 35,000
Proceeds from issuance of common stock, net of issuance costs \| $				$ 5,000
Stock Purchase Agreement \| Gilead \| Gilead Collaboration and License Agreement
Ownership percentage (in %)				19.90%
Amended Stock Purchase Agreement
Issuance of stock (in shares)		1,500,000
Share price (in USD per share) \| $ / shares		$ 14.167
Proceeds from issuance of common stock, net of issuance costs \| $		$ 21,250
Outstanding amount \| $		$ 8,750
Pre Reverse Stock Split \| Stock Purchase Agreement
Issuance of stock (in shares)				1,666,666
Pre Reverse Stock Split \| Amended Stock Purchase Agreement
Issuance of stock (in shares)		15,000,000
Common stock
Common stock, shares authorized (in shares)						40,000,000	20,000,000
Common stock, issued (in shares)						9,655,059	9,655,059
Common stock, outstanding (in shares)						9,655,022	9,655,022
Issuance of stock (in shares)			2,290,077
Share price (in USD per share) \| $ / shares			$ 13.1
Number of votes \| Vote							1
Conversion of preferred stock into common stock (in shares)					632,700
Common stock \| Stock Purchase Agreement
Share price (in USD per share) \| $ / shares							$ 14.167	$ 30
Common stock \| Pre Reverse Stock Split
Issuance of stock (in shares)			22,900,768
Conversion of preferred stock into common stock (in shares)					6,327,000
Class A common stock
Common stock, shares authorized (in shares)						3,900,000	3,900,000
Common stock, issued (in shares)						2,399,517	2,399,517
Common stock, outstanding (in shares)						2,399,517	2,399,517
Number of common stock issued upon conversion of each share (in shares)						10	10
Series A, Series A-1 And Series A-2 convertible Preferred Stock
Number of common stock issued upon conversion of each share (in shares)						100
Threshold percentage for conversion (in %)						9.99%
Liquidation preference per share (in $ per share) \| $ / shares						$ 0.001
Series A convertible preferred stock
Preferred stock shares designated (in shares)						2,978	2,978
Preferred stock, shares issued (in shares)						370
Preferred stock, shares outstanding (in shares)						370	370
Number of shares elected to convert (in shares)					1,327
Series A-1 convertible preferred stock
Preferred stock shares designated (in shares)						15,800	15,800
Preferred stock, shares issued (in shares)						10,800
Preferred stock, shares outstanding (in shares)						10,800	10,800
Number of shares elected to convert (in shares)					5,000
Series A-2 convertible preferred stock
Preferred stock shares designated (in shares)						15,268	15,268
Preferred stock, shares issued (in shares)						15,268
Preferred stock, shares outstanding (in shares)						15,268	15,268
Issuance of stock (in shares)			15,268
Share price (in USD per share) \| $ / shares			$ 1,310

Net loss per share (Tables)

12 Months Ended

Dec. 31, 2024

Net loss per share

Schedule of basic and diluted Net loss per share attributable to common stockholders

The following table sets forth the computation of the basic and diluted net loss per share attributable to common stockholders (in thousands, except for share and per share amounts):


	Year ended December 31,
	2024		2023		2022
Numerator:
Net loss	$	(43,503)	$	(81,580)	$	(64,915)

Denominator:
Weighted-average common shares outstanding, basic and diluted		9,894,994		7,242,268		5,074,308
Weighted-average Series A convertible preferred shares outstanding, basic and diluted, presented as if converted into common stock⁽¹⁾		37,000		83,536		169,700
Weighted-average Series A-1 convertible preferred shares outstanding, basic and diluted, presented as if converted into common stock⁽¹⁾		1,080,000		1,252,603		1,307,288
Weighted-average Series A-2 convertible preferred shares outstanding, basic and diluted, presented as if converted into common stock⁽¹⁾		1,526,800		874,250		—
Total number of shares used to calculate net loss per share, basic and diluted		12,538,794		9,452,657		6,551,296
Net loss per share, basic and diluted	$	(3.47)	$	(8.63)	$	(9.91)

⁽¹⁾ Class A common stock and Series A, Series A-1 and Series A-2 convertible preferred stock are participating securities that have substantially the same terms and features as the Company’s common stock. The Class A common stock and Series A, Series A-1 and Series A-2 convertible preferred stock are therefore included in the weighted-average number of shares outstanding to calculate net loss per share, basic and diluted as if converted into common stock. Each ten shares of Class A common stock and each share of Series A, Series A-1 and Series A-2 convertible preferred stock is independently convertible into one and 100 shares of common stock, respectively. In the year ended December 31, 2024, 239,952 shares of the Company’s common stock were issuable upon conversion of the Class A common stock, 37,000 shares of the Company’s common stock were issuable upon conversion of Series A convertible preferred stock, 1,080,000 shares of the Company’s common stock were issuable upon conversion of Series A-1 convertible preferred stock and 1,526,800 shares of the Company’s common stock were issuable upon conversion of Series A-2 convertible preferred stock (see Note 12).

Schedule of potentially dilutive securities that were not included in the diluted per share calculations


	Year ended December 31,
	2024	2023	2022
Options issued and outstanding	1,089,427	810,942	653,053
Unvested restricted stock units	369,070	—	—
Total	1,458,497	810,942	653,053

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
Document and Entity Information - USD ($) $ in Millions	Dec. 31, 2024	Feb. 24, 2025	Jun. 30, 2024
Document Information [Line Items]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2024
Document Transition Report	false
Entity File Number	001-38869
Entity Registrant Name	HOOKIPA PHARMA INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	81-5395687
Entity Address, Address Line One	350 Fifth Avenue, 72nd Floor, Suite 7240
Entity Address, City or Town	New York
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10118
Country Region	+43
City Area Code	1
Local Phone Number	890 63 60
Title of 12(b) Security	Common Stock, $0.0001 Par Value per Share
Trading Symbol	HOOK
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	false
Document Financial Statement Error Correction [Flag]	false
Entity Shell Company	false
Entity Public Float			$ 57.0
Auditor Name	PwC Wirtschaftsprüfung GmbH
Auditor Firm ID	1259
Auditor Location	Vienna, Austria
Entity Central Index Key	0001760542
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	FY
Amendment Flag	false
Common stock
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		9,659,522
Class A common stock
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		2,399,517

Commitments and contingencies

12 Months Ended

Dec. 31, 2024

Commitments and contingencies

Commitments and contingencies

15. Commitments and contingencies

Contract manufacturing arrangements

The Company has entered into arrangements with contract manufacturing organizations (“CMOs”) for manufacturing of materials for research and development purposes, including manufacturing of clinical trial materials. These contracts generally provide for non-cancellable obligations or cancellation penalties depending on the time of cancellation. As of December 31, 2024, the Company’s total non-cancellable obligations under contracts with CMOs were $4.7 million, which relates to 2025 deliverables.

Intellectual property licenses

The Company has entered into certain license agreements under which it is obligated to make milestone payments upon the achievement of certain development and regulatory milestones, to pay royalties on net sales of licensed products, and to pay a percentage of the sublicense fees which the Company receives from its sublicensees.

In the years ended December 31, 2024, 2023 and 2022, the Company recorded $3.6 million, $1.6 million and $1.0 million, respectively, in licensing fees related to intellectual property licenses as research and development expenses. The amount is mainly related to the upfront payment and milestone payments received by the Company under the Gilead Collaboration Agreement and the Roche Collaboration Agreement. The amount recognized as expenses has been agreed to by the licensors but calculation of sublicensing fees on future payments may be subject to interpretation and may change until agreed to by the receiving party.

Indemnification agreements

In the ordinary course of business, the Company may provide indemnification of varying scope and terms to vendors, lessors, business partners and other parties with respect to certain matters including, but not limited to, losses arising out of breach of such agreements or from intellectual property infringement claims made by third parties. In addition, the Company has entered into indemnification agreements with members of its board of directors and senior management that will require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or service as directors or officers. The maximum potential amount of future payments the Company could be required to make under these indemnification agreements is, in many cases, unlimited. To date, the Company has not incurred any material costs as a result of such indemnifications. The Company is not aware of any claims under indemnification arrangements, and it has not accrued any liabilities related to such obligations in its consolidated financial statements as of December 31, 2024 or December 31, 2023.

Legal proceedings

The Company is not currently a party to any material legal proceedings. From time to time, the Company may become involved in litigation or legal proceedings relating to claims arising in the ordinary course of business. At each reporting date, the Company evaluates whether or not a potential loss amount or a potential range of loss is probable and reasonably estimable under the provisions of the authoritative guidance that addresses accounting for contingencies. The Company expenses the costs related to such legal proceedings as incurred.

Leases (Tables)

12 Months Ended

Dec. 31, 2024

Leases

Summary of the effect of lease costs

The following table summarizes the effect of lease costs in the Company’s consolidated statements of operations and comprehensive loss (in thousands):


		Year ended		Year ended		Year ended
	Income statement location	December 31, 2024		December 31, 2023		December 31, 2022
Operating lease expenses	Research and development expenses	$	1,374	$	1,347		1,430
	General and administrative expenses		321		242		219
Finance lease amortization expenses	Research and development expenses		—		—		89
	General and administrative expenses		—		—		—
Interest on finance lease liabilities	Interest expenses		—		—		0
Sublease income	Other income (expense)		—		—		—
Net lease expense		$	1,695	$	1,589		1,738

Summary of maturities of operating lease liabilities

The minimum lease payments for the next five years and thereafter are expected to be as follows (in thousands):


	December 31, 2024
	Operating lease
2025		558
2026		208
2027		73
2028		73
2029		—
Thereafter		—
Total lease payments		912
Less: interest		37
Present value of lease liabilities	$	875

Schedule of weighted average remaining lease term and weighted average discount rate of operating leases

The weighted average remaining lease term and weighted average discount rate of operating leases are as follows:


	December 31,		December 31,
	2024		2023
Weighted average remaining lease term in years	2.0		3.7
Weighted average discount rate ⁽¹⁾	4.8	%	4.1	%

⁽¹⁾ The majority of the contracts are denominated in euros. The discount rate was determined on a currency-equivalent basis.

Receivable research incentive (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Feb. 28, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Research and Development Incentive Program [Line Items]
Income related to the incentive program recorded as grant income		$ 7,400	$ 10,900	$ 7,300
Receivable research incentives		23,380	18,760
Grant Income		7,396	11,193	$ 7,916
Austrian Research Incentive Program
Research and Development Incentive Program [Line Items]
Income related to the incentive program recorded as grant income			9,400
Receivable research incentives		23,200	17,300
Austrian Research Incentive Program \| Subsequent event
Research and Development Incentive Program [Line Items]
Proceeds from incentive program	$ 17,300
New York State Life Sciences Research and Development Program
Research and Development Incentive Program [Line Items]
Income related to the incentive program recorded as grant income			1,400
Receivable research incentives		100	1,400
Reimbursement of research and development expenses		500
New York State New York City Biotechnology Tax Credit Program
Research and Development Incentive Program [Line Items]
Income related to the incentive program recorded as grant income			100
Receivable research incentives		100	$ 100
Maximum expenses eligible for incentives		$ 250

Summary of significant accounting policies - Others (Details) $ in Millions	12 Months Ended
	Dec. 31, 2024 USD ($) Program item	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Summary of significant accounting policies
Amortization expense \| $	$ 0.1	$ 0.1	$ 0.1
Number of preclinical research programs \| Program	2
Number of Combined Performance Obligation	1
Number of combined performance obligation for each research program	1
Number of research program performance obligations	2
Maximum
Summary of significant accounting policies
Impairment loss \| $	$ (0.1)

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 83: http://www.xbrl.org/2003/role/disclosureRef
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Reference 84: http://www.xbrl.org/2003/role/disclosureRef
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Reference 85: http://www.xbrl.org/2003/role/disclosureRef
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Reference 87: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147480175/815-40-65-1

Reference 88: http://www.xbrl.org/2003/role/disclosureRef
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Reference 89: http://www.xbrl.org/2003/role/disclosureRef
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Reference 90: http://www.xbrl.org/2003/role/disclosureRef
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Reference 91: http://www.xbrl.org/2003/role/disclosureRef
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Reference 92: http://www.xbrl.org/2003/role/disclosureRef
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Reference 99: http://www.xbrl.org/2003/role/disclosureRef
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Reference 100: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Subsequent events

12 Months Ended

Dec. 31, 2024

Subsequent events

Subsequent events

20. Subsequent events

Potential combination of Poolbeg and HOOKIPA

On January 2, 2025, the Company and Poolbeg Pharma plc (“Poolbeg”) released an announcement pursuant to Rule 2.4 of the U.K. City Code on Takeovers and Mergers that the Company and Poolbeg entered into non-binding discussions for the potential acquisition of the entire issued share capital of Poolbeg to create a clinical-stage biopharmaceutical company focused on developing and commercializing innovative medicines for critical unmet medical needs, with a special focus on next-generation immunotherapies for the treatment of cancer and other serious diseases. On February 20, 2025, the Company issued an announcement pursuant to Rule 2.8 of the U.K. City Code on Takeovers and Mergers disclosing that the Company’s Board of Directors determined that it does not intend to make an

offer for Poolbeg under Rule 2.7 of the U.K. City Code on Takeovers and Mergers. Accordingly, the Company’s non-binding discussions with Poolbeg related to the Potential Combination have been terminated.

In connection with this potential combination, the Company has incurred transaction costs of $1.3 million in the year ended December 31, 2024 for consulting and professional services. These costs primarily relate to legal, financial advisory, and due diligence services.

Restructuring (Tables)

12 Months Ended

Dec. 31, 2024

Restructuring

Schedule of restructuring charges

The following table summarizes the effect of the restructuring charges (in thousands):


	Year ended December 31,
	2024		2023		2022
Restructuring expense
Severance and other personnel expenses	$	2,067	$	—	$	—
Professional fees, disposal costs and other related charges	$	597	$	—	$	—
Total	$	2,664	$	—	$	—

Schedule of roll-forward of cash restructuring-related liabilities


	Year ended December 31,
	2024		2023		2022
Restructuring expense
Severance and other personnel expenses	$	2,067	$	—	$	—
Professional fees, disposal costs and other related charges	$	597	$	—	$	—
Total	$	2,664	$	—	$	—

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Operating activities:
Net loss	$ (43,503)	$ (81,580)	$ (64,915)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	2,014	2,345	5,043
Depreciation and amortization expense	2,753	3,552	3,602
Impairment expense	4,004	12,766
Other non-cash items	0	64	160
Changes in operating assets and liabilities:
Accounts receivable	524	6,180	(341)
Receivable research incentives	(5,988)	(2,726)	(1,958)
Prepaid expenses and other current assets	(3,815)	1,735	2,007
Prepaid expenses and other non-current assets	(1,440)	304	424
Accounts payable	(1,570)	6,499	(1,999)
Deferred revenues	(27,538)	(8,258)	35,508
Operating lease liabilities	(1,591)	(1,622)	(1,584)
Accrued expenses and other liabilities	(828)	490	2,510
Other non-current liabilities		2,727	1,546
Net cash used in operating activities	(76,978)	(57,524)	(19,997)
Investing activities:
Purchases of property and equipment	(194)	(4,159)	(5,017)
Net cash used in investing activities	(194)	(4,159)	(5,017)
Financing activities:
Payments related to finance leases			(25)
Proceeds from issuance of convertible preferred stock, net of issuance costs		18,530	29,625
Proceeds from issuance of common stock, net of issuance costs		49,043	45,691
Payments for deferred offering costs	(135)	(149)	(195)
Repayments of borrowings	(1,141)	(1,754)	(2,825)
Net cash (used in) provided by financing activities	(1,276)	65,670	72,271
Net (decrease) increase in cash, cash equivalents and restricted cash	(78,448)	3,987	47,257
Cash, cash equivalents and restricted cash at beginning of period	117,521	113,444	66,912
Effect of exchange rate changes on cash, cash equivalents and restricted cash	813	90	(725)
Cash, cash equivalents and restricted cash at end of period	39,886	117,521	113,444
Supplemental disclosure of cash flow information:
Cash paid for interest	(2)	(14)	(32)
Cash paid for income taxes	(1)	(403)	(1)
Supplemental disclosure of non-cash financing activities:
Property and equipment additions in accounts payable and accrued expenses		(34)	(56)
Lease assets obtained in exchange for new operating lease liabilities	433	$ 2,874	$ 225
Lease assets derecognized upon lease modification	$ (3,219)

Related Parties (Details) - USD ($) $ in Millions	12 Months Ended
Related Parties (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Board of directors \| Malte Peters \| Consultancy services agreement
Related parties
Expense recorded	$ 0.2	$ 0.1

Summary of significant accounting policies (Policies)

12 Months Ended

Dec. 31, 2024

Summary of significant accounting policies

Basis of presentation

Going concern

Reverse Stock Split

Reverse stock split

Use of estimates

Foreign currency and currency translation

The functional currency for the Company is the United States dollar and the functional currency for the Company's wholly owned foreign subsidiary, HOOKIPA Biotech GmbH, is the euro.

Concentrations of credit risk and of significant suppliers

Deferred offering costs

Fair value measurements

●

Level 1 - Quoted prices in active markets for identical assets or liabilities.

●

The Company’s cash equivalents are carried at fair value, determined according to the fair value hierarchy described above (see Note 6).

Cash equivalents

Assets held for sale

Property and equipment


		Estimated useful life
Leasehold improvements		shorter of useful life or term of lease
Laboratory equipment		2 - 10 years
Furniture and fixtures		2 - 10 years
Computer equipment and software		2 - 4 years

Leases

Capitalized Software Development Cost

Impairment of long-lived assets

Restructuring

Segment information

The measure of segment assets is reported on the consolidated balance sheet as total assets.

Revenue recognition from collaboration and licensing

The Company recognized revenue from collaboration and license agreements with Gilead and Roche.

UCA Option constitutes a material right, and the determination of when milestone payments are probable of being received.

Upfront payment and program initiation fee

Reimbursement for services

Research and development milestones

Sales-based milestones and royalty payments

Cost to fulfill contracts

Research and development costs

Research and manufacturing contract costs and accruals

Government grant agreements and research incentives

Stock-based compensation

Comprehensive loss

Net loss per share

The Company reported a net loss attributable to common stockholders for the years ended December 31, 2024, 2023 and 2022.

Income taxes

Recent accounting pronouncements

Adopted as of current period

Recently Issued Accounting Pronouncements

Leases

12 Months Ended

Dec. 31, 2024

Leases

Leases

9. Leases

The Company leases real estate, including office and laboratory space and has entered into various other agreements with respect to assets used in conducting its business. The Company’s leases have remaining lease terms ranging from less than 1 year to 4.3 years. Some of the lease agreements contain rent holidays and rent escalation clauses that were included in the calculation of the right of use assets and lease liabilities. The Company’s current leases qualify as operating leases. The Company is required to maintain a cash balance of $0.2 million to secure letters of credit associated with real estate leases. $0.1 million of this amount were classified as non-current restricted cash and $0.1 million were classified as current restricted cash in the consolidated balance sheet as of December 31, 2024.

The following table summarizes the effect of lease costs in the Company’s consolidated statements of operations and comprehensive loss (in thousands):


		Year ended		Year ended		Year ended
	Income statement location	December 31, 2024		December 31, 2023		December 31, 2022
Operating lease expenses	Research and development expenses	$	1,374	$	1,347		1,430
	General and administrative expenses		321		242		219
Finance lease amortization expenses	Research and development expenses		—		—		89
	General and administrative expenses		—		—		—
Interest on finance lease liabilities	Interest expenses		—		—		0
Sublease income	Other income (expense)		—		—		—
Net lease expense		$	1,695	$	1,589		1,738

The minimum lease payments for the next five years and thereafter are expected to be as follows (in thousands):


	December 31, 2024
	Operating lease
2025		558
2026		208
2027		73
2028		73
2029		—
Thereafter		—
Total lease payments		912
Less: interest		37
Present value of lease liabilities	$	875

The weighted average remaining lease term and weighted average discount rate of operating leases are as follows:


	December 31,		December 31,
	2024		2023
Weighted average remaining lease term in years	2.0		3.7
Weighted average discount rate ⁽¹⁾	4.8	%	4.1	%

⁽¹⁾ The majority of the contracts are denominated in euros. The discount rate was determined on a currency-equivalent basis.

During the year ended December 31, 2024, the Company initiated the closing and consolidation of its office and laboratories in Vienna, Austria, which reduced the term of the related leases by approximately 2.5 years ending between the end of February 2025 and the end of June 2025. These lease terminations did not include additional right-of-use or lease liability other than the reduced lease term. The respective lease liabilities were remeasured and the amounts resulting from the remeasurement of the lease liabilities were recognized as an adjustment to the corresponding right of use assets.

Accrued expenses and other current liabilities

12 Months Ended

Dec. 31, 2024

Accrued expenses and other current liabilities

Accrued expenses and other current liabilities

10. Accrued expenses and other current liabilities

Accrued expenses and other current liabilities consisted of the following (in thousands):


	December 31,		December 31,
	2024		2023
Salaries and bonuses		4,193		5,665
Social security contributions		259		340
Unearned grant income		—		52
Accrued external research and development expenses		1,845		4,594
Accrued external general and administration expenses		2,921		292
Accrued for property and equipment acquisitions		—		14
Accrued for restructuring expenses		842		—
Income taxes		—		367
Other accruals and liabilities		592		777
	$	10,652	$	12,101

Stock-based compensation - Restricted Stock Units (Details) - Restricted Stock Units	1 Months Ended	12 Months Ended
	Jul. 31, 2024 installment	Dec. 31, 2024 $ / shares shares
Stock-based compensation
Number of equal installments of vesting \| installment	2
Number of Shares
Granted \| shares		369,070
Ending balance \| shares		369,070
Weighted Average Grant Date Fair Value
Granted \| $ / shares		$ 4.37
Ending balance \| $ / shares		$ 4.37

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 35
-Paragraph 1D
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480483/718-10-35-1D

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 35
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480483/718-10-35-3

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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Reference 18: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Stock-based compensation - Summary of awards outstanding (Details) - shares	Dec. 31, 2024	Dec. 31, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding (in shares)	1,089,427	810,942
2018 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding (in shares)	73,935
2019 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding (in shares)	975,492
Inducement Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding (in shares)	40,000

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Stock-based compensation - Stock option activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Number of Shares
Beginning balance	810,942
Granted		465,902
Exercised	0
Forfeited		(187,417)
Ending balance	1,089,427	810,942
Options exercisable	520,033
Options unvested	569,394
Weighted Average Exercise Price
Beginning balance	$ 42.76
Granted		$ 7.14
Forfeited		27.28
Ending balance	30.19	$ 42.76
Options exercisable	53.55
Options unvested	$ 8.85
Weighted Average Remaining Contractual Term
Weighted Average Remaining Contractual Term (in years)	5 years 6 months	7 years 4 months 24 days
Weighted Average Remaining Contractual Term, options exercisable (in years)	3 years 9 months 18 days
Weighted Average Remaining Contractual Term, options unvested (in years)	7 years 1 month 6 days
Aggregate Intrinsic Value, outstanding	$ 69	$ 486
Aggregate Intrinsic Value, options exercisable	$ 69
Fair value per common stock used for calculating intrinsic values (in $ per share)	$ 2.01	$ 8.1	$ 8.1
Weighted average grant-date fair value per share of stock options granted	$ 5.83	$ 5.52	$ 15.5
Total fair value of stock options vested	$ 2,300	$ 5,100
Cash was received from option exercise under share-based payment arrangements	$ 0	1	$ 3
Maximum
Weighted Average Remaining Contractual Term
Aggregate Intrinsic Value, options exercised		$ 100	$ 100

Stock-based compensation

12 Months Ended

Dec. 31, 2024

Stock-based compensation

Stock-based compensation

13. Stock-based compensation

2018 Stock Option and Grant Plan

In June 2018, the Company’s board of directors approved the 2018 Stock Option and Grant Plan. Options granted under the 2018 Stock Option and Grant Plan generally vest over four years, with 25% of the options vesting upon the first anniversary of the grant date and the remaining 75% of the options vesting in 12 equal quarterly installments following the first anniversary of the grant date, provided the option holder continues to have an employment or service relationship with the Company on each vesting date. The options expire on the 10^th anniversary of the grant date. As of December 31, 2024, 73,935 options granted under the 2018 Stock Option and Grant Plan remained outstanding. Any authorization to issue new options under the 2018 Stock Option and Grant Plan was cancelled upon the effectiveness of the 2019 Stock Option and Incentive Plan and no further awards will be granted under the 2018 Plan.

2019 Stock Option and Incentive Plan

On April 1, 2019, the Company’s stockholders approved the 2019 Stock Option and Incentive Plan, which became effective as of the effective date of the registration statement in connection with the Company’s IPO. The plan provides for the grant of shares of restricted stock, long term incentive awards, stock options or other equity-based awards. As of December 31, 2024, the maximum number of shares of the Company’s common stock that may be issued under the Company’s 2019 Stock Option and Incentive Plan was 1,202,548 shares which shall be cumulatively increased on January 1 of each year by up to 4.0% of the then outstanding number of shares of common stock and Class A common stock. Options granted under the 2019 Stock Option and Incentive Plan generally vest over four years, with 25% of the options vesting upon the first anniversary of the grant date and the remaining 75% of the options vesting in 12 equal quarterly installments following the first anniversary of the grant date, provided the option holder continues to have an employment or service relationship with the Company on each vesting date. Initial options granted to non-executive directors upon their election generally vest over a three-year term with 33% of the options vesting upon the first anniversary of the grant date and the remaining 67% of the options vesting in eight equal quarterly installments following the first anniversary of the grant date and the next annual meeting of stockholders. Annual option re-grants to non-executive directors generally vest on the earlier of the first anniversary of the grant date. The options expire on the 10^th anniversary of the grant date. For each option the beneficiary is entitled to receive one share of common stock upon the exercise of the option.

On August 7, 2023, the Company’s board of directors approved a one-time offer to eligible non-executive, non-director employees to exchange certain outstanding stock options for new stock options with modified terms. Under the stock option exchange program (the “Offer”), the Company offered to exchange certain out-of-the-money stock options for new stock options at an exchange ratio of between 1.75 and 2.50 surrendered options for one new option exercisable for shares of common stock with a lower exercise price and extended vesting terms. Pursuant to the Offer, a total of 82 eligible participants tendered, and the Company accepted for cancellation, stock options to purchase an aggregate of 54,323 shares of the Company’s common stock with exercise prices between $69.00 and $140.00. The eligible options that were accepted for cancellation represented approximately 86.6% of the total shares of common stock underlying all of the eligible options. In accordance with the terms and conditions of the Offer, on September 12, 2023, the Company issued new options to purchase an aggregate of 27,376 shares of common stock in exchange for the cancellation of the tendered eligible options. The exercise price per share of each new option granted in the Offer is $10.00. New options issued for previously vested stock options vest on the first anniversary of the grant date and new options issued for previously unvested stock options vest over a three-year term in twelve equal quarterly installments. The stock option exchange offer resulted in incremental stock-based compensation expense of $0.1 million, recognized using the graded-vesting method over the remaining requisite service period of the new stock options.

2023 Inducement Plan

On April 7, 2023, the Company’s board of directors adopted the Company’s 2023 Inducement Plan (the “2023 Inducement Plan”) pursuant to which the Company reserved 50,000 shares of common stock for issuance under the 2023 Inducement Plan. The 2023 Inducement Plan provides for the grant of non-statutory stock options to eligible individuals. In accordance with Nasdaq Marketplace Rule 5635(c)(4), awards under the 2023 Inducement Plan may only be made to individuals not previously employees or directors of the Company (or following such individuals’ bona fide period of non-employment with the Company), as an inducement material to the individuals’ entry into employment with the Company. Awards granted under the 2023 Inducement Plan must be approved by either a majority of the Company’s independent directors or the compensation committee of the Company’s board of directors. As of December 31, 2024, the Company had 10,000 shares of its common stock available for future issuance under the 2023 Inducement Plan.

The following table presents a summary of awards outstanding:



	As of December 31, 2024
	2018 Plan	2019 Plan	Inducement Awards	Total
Granted and outstanding awards:
Stock options	73,935	975,492	40,000	1,089,427
Total	73,935	975,492	40,000	1,089,427

Stock option valuation

The Company estimates the option’s fair value on the date of grant using the Black-Scholes option-pricing model. Black-Scholes utilizes assumptions related to expected term, volatility, the risk-free interest rate, the dividend and employee exercise behavior. Forfeitures are accounted for when they occur. Expected volatilities utilized in the Black-Scholes model are based on historical volatilities of a group of comparable companies. The group of representative companies have characteristics similar to the Company, including the stage of product development and focus on the life science industry. Management believes that this represents the most accurate basis for estimating expected future volatilities under the current conditions. The risk-free interest rate is derived from the yields for U.S. Treasuries with a remaining term approximating the expected life of the options. The expected term represents the period of time that the options granted are expected to be outstanding.

The following table summarizes the assumptions used in the Black-Scholes option-pricing model for estimating the fair value of stock options granted during:


	Year ended December 31,
	2024		2023		2022

Risk-free interest rate	4.48	%	3.70	%	3.09	%
Expected term (in years)	6.1		5.7		6.0
Expected volatility	101.7	%	93.6	%	85.4	%
Expected dividends	—	%	—	%	—	%

For the 2024, 2023 and 2022 grants, the Company used the simplified method in developing an estimate of the expected term due to a lack of historical exercise data.

Stock option activity

The following table summarizes the Company’s stock option activity since January 1, 2024 (in thousands, except share and per share amounts):


				Weighted
		Weighted		Average
		Average		Remaining	Aggregate
	Number of	Exercise		Contractual	Intrinsic
	Shares	Price		Term	Value
				(in years)
Outstanding as of December 31, 2023	810,942	$	42.76	7.4	$	486
Granted	465,902		7.14
Exercised	—		—
Forfeited	(187,417)		27.28
Outstanding as of December 31, 2024	1,089,427	$	30.19	5.5	$	69

Options exercisable as of December 31, 2024	520,033	$	53.55	3.8	$	69
Options unvested as of December 31, 2024	569,394	$	8.85	7.1	$	—

The aggregate intrinsic value of stock options was calculated as the difference between the exercise price of the stock options and the fair value of the Company’s common stock for those stock options that had exercise prices lower than the fair value of the Company’s common stock. The fair value per common stock used for calculating the intrinsic values as of December 31, 2024, December 31, 2023 and December 31, 2022, was $2.01, $8.10 and $8.10, respectively.

No options were exercised during the year ended December 31, 2024. The aggregate intrinsic value of options exercised during the years ended December 31, 2023 and 2022 was less than $0.1 million and $0.1 million, respectively.

The weighted average grant-date fair value per share of stock options granted during the years ended December 31, 2024, 2023 and 2022 was $5.83, $5.52 and $15.50, respectively.

The total fair value of stock options vested during the years ended December 31, 2024 and 2023 was $2.3 million and $5.1 million, respectively.

No cash was received from stock option exercises under share-based payment arrangements for the year ended December 31, 2024. Cash received from stock option exercises under share-based payment arrangements for the years ended December 31, 2023 and 2022 was $1 thousand and $3 thousand, respectively.

Restricted Stock Units

In July 2024, the Company granted restricted stock units with time-based vesting conditions to officers. The restricted stock units vest in two equal installments in July 2025 and in July 2026. In December 2024, the Company granted restricted stock units with time-based vesting conditions to employees. The restricted stock units vest in two equal installments in March 2025 and in December 2025. The Company measures the fair value of restricted stock units on the date of grant using the underlying common stock fair value. Expenses are recorded using the graded-vesting method.

The table below summarizes the Company’s restricted stock unit activity since December 31, 2023:


		Weighted
		Average Grant
	Number of	Date Fair
	Shares	Value
Outstanding as of December 31, 2023	—	$	—
Granted	369,070		4.37
Vested	—		—
Forfeited	—		—
Outstanding as of December 31, 2024	369,070	$	4.37

Stock-based compensation

Stock-based compensation expense was classified in the consolidated statements of operations and comprehensive loss as follows (in thousands):


	Year ended December 31,
	2024		2023		2022
Research and development expenses⁽¹⁾	$	523	$	861	$	2,074
General and administrative expenses⁽¹⁾		1,491		1,484		2,969
	$	2,014	$	2,345	$	5,043

As of December 31, 2024 total unrecognized compensation costs related to the unvested stock-based awards were $1.5 million, which are expected to be recognized over a weighted average period of 1.6 years.

Fair Value of Financial Assets

12 Months Ended

Dec. 31, 2024

Fair Value of Financial Assets

Fair Value of Financial Assets

6. Fair Value of Financial Assets

The following tables present information about the Company’s financial assets measured at fair value on a recurring basis and indicating the level of the fair value hierarchy utilized to determine such fair values (in thousands):


	Fair Value Measurement at December 31, 2024
	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	13,200	$	—	$	—	$	13,200
Assets held for sale		—		—		2,216		2,216
Total	$	13,200	$	—	$	2,216	$	15,416


	Fair Value Measurement at December 31, 2023
	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	91,084	$	—	$	—	$	91,084
Total	$	91,084	$	—	$	—	$	91,084

During the year ended December 31, 2024, there were no transfers between Level 1, Level 2 and Level 3.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 107
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-107

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 100
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-100

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2E
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2E

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 940
-SubTopic 820
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478119/940-820-50-1

+ Details

Net loss per share (Details) - USD ($)
$ / shares in Units, $ in Thousands

12 Months Ended

Dec. 31, 2024

Dec. 31, 2023

Dec. 31, 2022

Numerator:

Net Income (Loss)

$ (43,503)

$ (81,580)

$ (64,915)

Denominator:

Weighted-average Shares outstanding, basic

12,538,794

9,452,657

6,551,296

Weighted-average Shares outstanding, diluted

12,538,794

9,452,657

6,551,296

Net loss per share, basic

^[1]

$ (3.47)

$ (8.63)

$ (9.91)

Net loss per share, diluted

^[1]

$ (3.47)

$ (8.63)

$ (9.91)

Common stock

Denominator:

Weighted-average Shares outstanding, basic

9,894,994

7,242,268

5,074,308

Weighted-average Shares outstanding, diluted

9,894,994

7,242,268

5,074,308

Series A convertible preferred stock

Denominator:

Weighted-average Shares outstanding, basic

37,000

83,536

169,700

Weighted-average Shares outstanding, diluted

37,000

83,536

169,700

Number of shares issued for each share of common stock

100

Number of common stock issuable upon conversion of convertible preferred stock

37,000

Series A-1 convertible preferred stock

Denominator:

Weighted-average Shares outstanding, basic

1,080,000

1,252,603

1,307,288

Weighted-average Shares outstanding, diluted

1,080,000

1,252,603

1,307,288

Number of common stock issued upon conversion of each share of Preferred Stock

100

Number of common stock issuable upon conversion of convertible preferred stock

1,080,000

Series A-2 convertible preferred stock

Denominator:

Weighted-average Shares outstanding, basic

1,526,800

874,250

Weighted-average Shares outstanding, diluted

1,526,800

874,250

Number of common stock issued upon conversion of each share of Preferred Stock

100

Number of common stock issuable upon conversion of convertible preferred stock

1,526,800

Class A common stock

Denominator:

Number of common stock issued upon conversion of each share (in shares)

Number of shares issued for each share of common stock

Number of common shares issuable upon conversion of common stock

239,952

[1]	Share and per share amounts have been restated to reflect the one-for-ten reverse stock split effected in July 2024 on a retroactive basis for all periods presented.

Summary of significant accounting policies - Comprehensive loss (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Summary of significant accounting policies
Foreign currency translation adjustment, net of tax	$ 2,846	$ (777)	$ (2,376)

Income taxes - Changes in the valuation allowance for deferred tax assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Income taxes
Valuation allowance at beginning of period	$ (89,309)	$ (65,774)	$ (53,728)
Increases	(4,073)	(23,535)	(12,046)
Valuation allowance at end of period	$ (93,382)	$ (89,309)	$ (65,774)

Restructuring - Roll-forward cash restructuring-related liabilities (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2024 USD ($)
Restructuring Cost and Reserve [Line Items]
Severance and other personnel costs, professional fees and other related charges	$ 2,664
Total charges	(1,822)
Ending Balance	842
Severance and other personnel costs
Restructuring Cost and Reserve [Line Items]
Severance and other personnel costs, professional fees and other related charges	2,067
Total charges	(1,493)
Ending Balance	574
Professional fees and other related charges
Restructuring Cost and Reserve [Line Items]
Severance and other personnel costs, professional fees and other related charges	597
Total charges	(329)
Ending Balance	$ 268

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References + Details

Impairment

12 Months Ended

Dec. 31, 2024

Restructuring

Impairment

5. Impairment

As a result of the targeted cost-savings, restructuring actions, and strategic considerations resulting from the adoption of the restructuring plan, which included the termination of a part of the Company’s rented office and laboratory space in Vienna, Austria, the Company assessed the recoverability of the long-lived assets relating to the leasehold improvements, laboratory equipment, furniture and fixtures, and computer equipment and software at December 31, 2024, and determined that the undiscounted cash flows of certain asset groups were below the carrying values, indicating impairment. The carrying values of the assets were written down to their estimated fair value, which was determined based on the cost approach. The impairment test was performed as of December 31, 2024 and the fair values are classified as Level 3 of the fair value hierarchy due to a mix of unobservable inputs utilized such as assumptions and estimates for the current replacement costs of similar assets adjusted for estimated depreciation and deterioration of the existing equipment and economic obsolescence, independent research in the market as well as actual quotes from market participants.

For the year ended December31, 2023, as a result of strategic considerations preceding the adoption of a restructuring plan, the Company assessed the recoverability of the long-lived assets relating to the GMP manufacturing project at December 31, 2023, and determined that the undiscounted cash flows of the asset group were below the carrying values, indicating impairment. The assets were written down to their estimated fair value, which was determined based on the cost approach.

The following table summarizes the effect of non-cash impairment charges, which are included within Impairment expense in the consolidated statements of operations and comprehensive loss (in thousands):


	Year ended December 31,
	2024		2023		2022
Non-cash impairment charges
Asset write-offs	$	(4,004)	$	(12,766)	$	—
Total non-cash impairment charges	$	(4,004)	$	(12,766)	$	—

Loans payable (Details) - USD ($) $ in Thousands	12 Months Ended
Loans payable (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Loans payable
Loans from FFG		$ 1,172
Unamortized debt discount		(52)
Total loans payable, net	$ 0	1,120
Revenue	43,946	20,129	$ 14,249
Unamortized debt discount loans	0	100
Principal payment	1,141	1,754	2,825
Amortization of debt discount	$ 100	300	700
Estimated market rate	20.00%
Threshold for change in estimated market rate	0.10
Grant
Loans payable
Revenue	$ 0	300	600
Maximum
Loans payable
Interest expense	100	300	$ 700
Maximum \| Grant
Loans payable
Contract with Customer, Liability, Current	$ 0	$ 100

Net loss per share

12 Months Ended

Dec. 31, 2024

Net loss per share

Net loss per share

17. Net loss per share

The following table sets forth the computation of the basic and diluted net loss per share attributable to common stockholders (in thousands, except for share and per share amounts):


	Year ended December 31,
	2024		2023		2022
Numerator:
Net loss	$	(43,503)	$	(81,580)	$	(64,915)

Denominator:
Weighted-average common shares outstanding, basic and diluted		9,894,994		7,242,268		5,074,308
Weighted-average Series A convertible preferred shares outstanding, basic and diluted, presented as if converted into common stock⁽¹⁾		37,000		83,536		169,700
Weighted-average Series A-1 convertible preferred shares outstanding, basic and diluted, presented as if converted into common stock⁽¹⁾		1,080,000		1,252,603		1,307,288
Weighted-average Series A-2 convertible preferred shares outstanding, basic and diluted, presented as if converted into common stock⁽¹⁾		1,526,800		874,250		—
Total number of shares used to calculate net loss per share, basic and diluted		12,538,794		9,452,657		6,551,296
Net loss per share, basic and diluted	$	(3.47)	$	(8.63)	$	(9.91)

Since the Company was in a loss position for all periods presented, basic net loss per share is the same as diluted net loss per share for all periods as the inclusion of all potential common shares (common stock and Class A common stock) outstanding would have been anti-dilutive. Potentially dilutive securities that were not included in the diluted per share calculations because they would be anti-dilutive were as follows:


	Year ended December 31,
	2024	2023	2022
Options issued and outstanding	1,089,427	810,942	653,053
Unvested restricted stock units	369,070	—	—
Total	1,458,497	810,942	653,053

Income taxes - Additional Information (Details) - USD ($)	12 Months Ended			24 Months Ended	36 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2023	Dec. 31, 2024
Operating Loss Carryforwards [Line Items]
Corporate income tax rate	21.00%	21.00%	21.00%		21.00%
Global Intangible Low Taxed Income estimated		$ 8,800,000
U.S. tax on GILTI, net of research credits		400,000
Unrecognized income tax benefits	$ 0	0		$ 0	$ 0
Federal
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	9,500,000	2,200,000	$ 13,800,000	2,200,000	9,500,000
After Method Change [member] \| Federal
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards		10,500,000		10,500,000
Austria
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	$ 400,900,000	$ 378,100,000	$ 275,300,000	$ 378,100,000	$ 400,900,000
Corporate income tax rate	23.00%	24.00%		25.00%

Stock-based compensation - 2018 Stock Option and Grant Plan (Details)	12 Months Ended
	Dec. 31, 2024 installment shares	Dec. 31, 2023 shares
Stock-based compensation
Options outstanding (in shares)	1,089,427	810,942
2018 Stock Option and Grant Plan
Stock-based compensation
Vesting period (in years)	4 years
Options outstanding (in shares)	73,935
2018 Stock Option and Grant Plan \| Vesting upon first anniversary
Stock-based compensation
Percentage of options vesting (in %)	25.00%
2018 Stock Option and Grant Plan \| Vesting in equal quarterly installments
Stock-based compensation
Percentage of options vesting (in %)	75.00%
Number of quarterly installments for vesting \| installment	12

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Related Parties

12 Months Ended

Dec. 31, 2024

Related Parties

Related Parties

18. Related parties

Effective September 15, 2023, Malte Peters, a member of the Company’s board of directors, agreed to lead the Company’s clinical activities as ad interim Senior Clinical Advisor. During the years ended December 31, 2024 and December 31, 2023, the Company recorded expense of $0.2 million and $0.1 million, respectively, related to a consultancy services agreement entered into with Dr. Peters, effective September 15, 2023. The consultancy services agreement was terminated on March 31, 2024. In the year ended December 31, 2022 the Company did not record any related party transactions.

- Definition

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-5

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-6

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(g)(3))
-Publisher FASB
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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-Name Accounting Standards Codification
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-Subparagraph (SX 210.6-07(2)(c))
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-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(e))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/850/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
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-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-6

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
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-URI https://asc.fasb.org/1943274/2147483326/850-10-50-1

+ Details

Stock-based compensation (Tables)

12 Months Ended

Dec. 31, 2024

Stock-based compensation

Schedule of awards outstanding



	As of December 31, 2024
	2018 Plan	2019 Plan	Inducement Awards	Total
Granted and outstanding awards:
Stock options	73,935	975,492	40,000	1,089,427
Total	73,935	975,492	40,000	1,089,427

Schedule of assumptions used in the Black-Scholes option-pricing model for estimating the fair value of stock options granted


	Year ended December 31,
	2024		2023		2022

Risk-free interest rate	4.48	%	3.70	%	3.09	%
Expected term (in years)	6.1		5.7		6.0
Expected volatility	101.7	%	93.6	%	85.4	%
Expected dividends	—	%	—	%	—	%

Schedule of stock option activity

The following table summarizes the Company’s stock option activity since January 1, 2024 (in thousands, except share and per share amounts):


				Weighted
		Weighted		Average
		Average		Remaining	Aggregate
	Number of	Exercise		Contractual	Intrinsic
	Shares	Price		Term	Value
				(in years)
Outstanding as of December 31, 2023	810,942	$	42.76	7.4	$	486
Granted	465,902		7.14
Exercised	—		—
Forfeited	(187,417)		27.28
Outstanding as of December 31, 2024	1,089,427	$	30.19	5.5	$	69

Options exercisable as of December 31, 2024	520,033	$	53.55	3.8	$	69
Options unvested as of December 31, 2024	569,394	$	8.85	7.1	$	—

Schedule of restricted stock units


		Weighted
		Average Grant
	Number of	Date Fair
	Shares	Value
Outstanding as of December 31, 2023	—	$	—
Granted	369,070		4.37
Vested	—		—
Forfeited	—		—
Outstanding as of December 31, 2024	369,070	$	4.37

Schedule of stock-based compensation expense

Stock-based compensation expense was classified in the consolidated statements of operations and comprehensive loss as follows (in thousands):


	Year ended December 31,
	2024		2023		2022
Research and development expenses⁽¹⁾	$	523	$	861	$	2,074
General and administrative expenses⁽¹⁾		1,491		1,484		2,969
	$	2,014	$	2,345	$	5,043

Loans payable (Tables)

12 Months Ended

Dec. 31, 2024

Loans payable

Schedule of loans payable

As of December 31, 2024 and December 31, 2023, loans payable consisted of the following (in thousands):


	December 31,		December 31,
	2024		2023
Loans from FFG	$	—	$	1,172
Unamortized debt discount		—		(52)
Total loans payable, net	$	—	$	1,120

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Current assets:
Cash and cash equivalents	$ 39,684	$ 117,096
Restricted cash	98
Accounts receivable	290	511
Receivable research incentives	23,380	18,760
Assets held or sale	2,216
Prepaid expenses and other current assets	14,997	10,749
Total current assets	80,665	147,116
Non-current assets:
Restricted cash	104	425
Property, plant and equipment, net	179	7,742
Operating lease right of use assets	885	5,473
Prepaid expenses and other non-current assets	712	581
Total non-current assets	1,880	14,221
Total assets	82,545	161,337
Current liabilities
Accounts payable	8,687	12,498
Deferred revenues	4,762	14,631
Operating lease liabilities, current	552	1,638
Accrued expenses and other current liabilities	10,652	12,101
Loans payable, current		1,120
Total current liabilities	24,653	41,988
Non-current liabilities
Operating lease liabilities, non-current	323	3,801
Deferred revenues, non-current	725	19,674
Other non-current liabilities	5,630	6,017
Total non-current liabilities	6,678	29,492
Total liabilities	31,331	71,480
Stockholders' equity:
Preferred Stock	0	0
Additional paid-in capital	469,064	467,050
Accumulated other comprehensive loss	(5,087)	(7,933)
Accumulated deficit	(412,764)	(369,261)
Total stockholders' equity	51,214	89,857
Total liabilities and stockholders' equity	82,545	161,337
Common stock
Stockholders' equity:
Common stock	1	1
Class A common stock
Stockholders' equity:
Common stock	$ 0	$ 0

Fair Value of Financial Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Fair Value of Financial Assets
Transfers from Level 1 to Level 2	$ 0
Transfers from Level 2 to Level 1	0
Transfers from into Level 3	0
Transfers from out of Level 3	0
Recurring
Fair Value of Financial Assets
Assets held for sale	2,216
Total	15,416	$ 91,084
Recurring \| Money market funds
Fair Value of Financial Assets
Cash equivalents	13,200	91,084
Recurring \| Level 1
Fair Value of Financial Assets
Total	13,200	91,084
Recurring \| Level 1 \| Money market funds
Fair Value of Financial Assets
Cash equivalents	13,200	$ 91,084
Recurring \| Level 3
Fair Value of Financial Assets
Assets held for sale	2,216
Total	$ 2,216

Stock-based compensation - Stock-based compensation expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Stock-based compensation
Stock-based compensation expense	$ 2,014	$ 2,345	$ 5,043
Unrecognized compensation cost related to the unvested stock-based awards	$ 1,500
Weighted average periods over which expense is expected to be recognized	1 year 7 months 6 days
Research and development expenses
Stock-based compensation
Stock-based compensation expense	$ 523	861	2,074
General and administrative expense
Stock-based compensation
Stock-based compensation expense	$ 1,491	$ 1,484	$ 2,969

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Reportable segments

12 Months Ended

Dec. 31, 2024

Reportable segments

Reportable segments

19. Reportable segments

The following represents segment information for the Company’s single operating segment, for the periods presented (in thousands):


	Year ended December 31,
	2024		2023		2022
Revenue	$	43,946	$	20,129	$	14,249
Add (deduct):
Direct research and development expense	$	(39,635)	$	(48,168)	$	(35,828)
Consulting and professional services expense		(11,728)		(10,088)		(11,464)
Personnel expenses, excluding stock-based compensation⁽¹⁾		(27,830)		(33,670)		(22,348)
Stock-based compensation		(2,014)		(2,345)		(5,043)
Depreciation and amortization expense⁽²⁾		(1,107)		(1,955)		(1,865)
Other segment items⁽³⁾		(8,940)		(10,091)		(3,332)
Interest income		3,701		5,293		1,633
Interest expense		(2)		(317)		(687)
Income tax benefit (expense)	$	106	$	(368)	$	(230)
Segment net loss	$	(43,503)	$	(81,580)	$	(64,915)

Adjustments and reconciling items	$	—	$	—	$	—
Consolidated net loss	$	(43,503)	$	(81,580)	$	(64,915)

⁽¹⁾ Personnel expenses include expenses for personnel, recruiting, training and travel

⁽²⁾ Depreciation and amortization expenses include depreciation for assets held for sale

⁽³⁾ Other segment items primarily include expenses for restructuring, impairment, other overhead, as well as foreign currency exchange gains and losses, and grant income

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

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+ Details

Property, plant and equipment, net and assets held for sale

12 Months Ended

Dec. 31, 2024

Property, plant and equipment, net and assets held for sale

Property, plant and equipment, net and assets held for sale

7. Property, plant and equipment, net and assets held for sale

Property, plant and equipment, net consisted of the following (in thousands):


	December 31,		December 31,
	2024		2023
Land	$	—	$	2,025
Leasehold improvements		3,095		3,300
Construction in progress		8		212
Laboratory equipment		—		8,722
Furniture and fixtures		601		654
Computer equipment and software		2,361		2,652
Property and equipment, gross		6,065		17,565
Less: Accumulated depreciation		(5,886)		(9,823)
Property and equipment, net	$	179	$	7,742

The decrease in property and equipment, net is driven by the reclassification of land and laboratory equipment to assets held for sale as of December 31, 2024, as well as impairment charges resulting from the adoption of the Restructuring Plan, which included the termination of a part of the Company’s rented office and laboratory space in Vienna, Austria.

Depreciation expense for continuing operations for the years ended December 31, 2024, 2023 and 2022 was $0.4 million, $2.0 million and $1.9 million, respectively.

In the year ended December 31, 2024 the Company recognized an impairment loss of $4.0 million. In the year ended December 31, 2023 the Company recognized an impairment loss of $12.8 million related to the GMP manufacturing facility project, which reduced the carrying value of this asset group to zero (see Note 5). There were no impairments in the year ended December 31, 2022. Impairment charges are included within Impairment expense in the consolidated statements of operations and comprehensive loss.

As of December 31, 2024, the following assets, all located in Vienna, Austria, were classified as held for sale and are presented as held for sale in the Company’s consolidated balance sheet as of December 31, 2024:


	Balance as of		Additions to Assets				Balance as of
Assets	December 31, 2023		Held for Sale		Assets Sold		December 31, 2024
Land	$	—	$	1,895	$	—	$	1,895
Laboratory equipment		—		321		—		321
Total	$	—					$	2,216

In December 2024, the Company began to actively market the land in Vienna, Austria, which was intended to use for the discontinued GMP manufacturing facility project. As such, the land has been reclassified as held for sale as of December 31, 2024. This asset is recognized at the lower of net book value or fair value less costs to sell. The Company evaluated the fair value of the land and determined fair value less costs to sell exceeded net book value. Accordingly, no impairment on the land was recorded during the year ended December 31, 2024. As a result of the termination of a part of the Company’s rented office and laboratory space in Vienna, Austria, the Company had $0.3 million in laboratory equipment that met the criteria for classification as held for sale. These assets are recognized at the lower of net book value or fair value less costs to sell using a market approach. The Company evaluated the fair value of its assets held for sale and determined fair value of the assets held for sale less costs to sell to be lower than net book value. Accordingly, the Company recorded an impairment of $3.6 million on laboratory equipment held for sale during the year ended December 31, 2024 to reflect the difference between net book value and the fair value less costs to sell of assets held for sale. Such impairment charges are included within Impairment expense in the consolidated statements of operations and comprehensive loss.

Net loss per share - Antidilutive securities (Details) - shares	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Anti-dilutive securities
Anti-dilutive shares	1,458,497	810,942	653,053
Options issued and outstanding
Anti-dilutive securities
Anti-dilutive shares	1,089,427	810,942	653,053
Unvested restricted stock units
Anti-dilutive securities
Anti-dilutive shares	369,070

Collaboration and Licensing Agreements

12 Months Ended

Dec. 31, 2024

Collaboration and Licensing Agreements

Collaboration and Licensing Agreements

3. Collaboration and Licensing Agreements

Gilead Collaboration and License Agreement

In June 2018, the Company entered into the Gilead Collaboration Agreement whereby the Company and Gilead agreed to collaborate with respect to two preclinical research programs to evaluate potential vaccine products for the treatment, cure, diagnosis or prevention of HBV and HIV. In February 2022, the Company signed the Amended and Restated Collaboration Agreement, which altered key aspects of the collaboration pertaining to the HIV therapeutic. Most importantly, the Amended and Restated Collaboration Agreement allocated additional research and development responsibility to the Company with respect to the Company’s HIV candidate and provided for additional funding by Gilead of such research and development activities as well as increased later stage development and commercial milestone payments.

Under the Gilead Collaboration Agreement, the Company granted Gilead an exclusive, royalty-bearing license to the Company’s technology platforms. Upon entering into the agreement in June 2018, the Company received a non-refundable $10.0 million upfront payment from Gilead and upon signing of the Restated Gilead Collaboration Agreement in February 2022, the Company received a program initiation fee of $15.0 million. Gilead is also obligated to make additional payments to the Company upon the achievement of pre-clinical, development and commercial milestones. The development milestones amount to $140.0 million for the HBV program, and up to $172.5 million for the HIV program, inclusive of a $10.0 million program completion fee, payable upon Gilead’s exercise of the option to pursue further development activities post Phase 1b. The commercial milestones amount to a total of $50.0 million for the HBV program, and $65.0 million for the HIV program. Additionally, Gilead is obligated to pay royalties on net sales for each program. Payments from Gilead generally have a 60 day payment term.

The $10.0 million upfront payment, the $15.0 million initiation fee and $13.0 million in milestone payments were initially recorded as deferred revenue in the consolidated balance sheet and are recognized as revenue when revenue recognition criteria are met. As of December 31, 2024, $5.5 million of such payments were still recorded as a liability in deferred revenues, current and non-current. As of December 31, 2023, $7.5 million of upfront and milestone payments were included as a liability in deferred revenues, current and non-current. Approximately 87% of deferred revenue is expected to be recognized as revenue in 2025 and the remaining 13% in 2026.

In the year ended December 31, 2024, the Company recognized $6.7 million of the milestone and initiation payments that were originally recorded as deferred revenue. Furthermore, the Company recognized $0.8 million revenue from cost reimbursements for research and development services. In the year ended December 31, 2023, the Company recognized $7.1 million of the upfront and milestone payments that were originally recorded as deferred revenue and $1.4 million revenue from cost reimbursements for research and development services. In the year ended December 31, 2022, the Company recognized $3.7 million of the upfront and milestone payments that were originally recorded as deferred revenue, $5.2 million revenue from cost reimbursements for research and development services and $5.0 million revenue from a milestone achieved in December 2022.

Sublicense fees payable to certain licensors of technologies upon the receipt of the deferred upfront and milestone payments, were capitalized as a contract asset and will be amortized over the period in which the revenue from the triggering payment is recognized. As of December 31, 2024 and 2023, the contract asset relating to the sublicense payment was $0.2 million and $0.1 million, respectively, and there was no liability relating to sublicense payment.

Roche Collaboration and License Agreement

In October 2022, the Company entered into the Roche Collaboration Agreement whereby the Company and Roche agreed to collaborate with respect to the development of novel arenaviral immunotherapies for KRAS-mutated cancers and, potentially, a second, novel arenaviral immunotherapeutic program targeting specific undisclosed cancer antigens. In January 2024, Roche provided written notice of the termination of the Roche Collaboration Agreement to the Company. The termination was made according to Roche’s right to terminate without cause, acknowledging that the Company had met all go-forward criteria under the agreement. Pursuant to the terms of the Roche Collaboration Agreement, following the termination notice, the Roche Collaboration Agreement terminated on April 25, 2024.

Under the terms of the original Roche Collaboration Agreement, the Company had granted Roche an exclusive, royalty-bearing license to the Company’s technology platforms for KRAS-mutated cancers, and an option right to exclusively license a second, novel arenaviral immunotherapeutic program targeting undisclosed cancer antigens. Upon the termination effective date of April 25, 2024, the Company regained full control of the associated intellectual property portfolio and full collaboration and licensing rights for this program.

Upon signing the Roche Collaboration Agreement in October 2022, the Company received a non-refundable upfront payment of $25.0 million. This upfront payment, a $10.0 million milestone payment received in the three months ended March 31, 2023, and a $10.0 million milestone payment received in the three months ended June 30, 2024 were considered as part of the transaction price and were recognized as revenue when revenue recognition criteria were met over the period in which services were performed. As of December 31, 2024, no liabilities were recorded in deferred revenues, current and non-current. As of December 31, 2023, $26.8 million of such payments were included as a liability in deferred revenues, current and non-current.

The Company considered the termination by Roche as a contract modification of the combined performance obligations and the transaction price. The modification was accounted for on a cumulative catch-up basis, applying the revised percent of completion to the revised transaction price, resulting in an immediate increase of revenue in the period of the modification. The transaction price was recognized as revenue over the remaining performance period using updated total estimated research and development costs.

In the year ended December 31, 2024, the Company recognized revenues of $36.3 million of the upfront and milestone payments that were originally recorded as deferred revenue. Furthermore, the Company recognized $0.1 million of revenue from cost reimbursements for activities related to the preparation of a first in human trial of HB-700. In the year ended December 31, 2023, the Company recognized $11.1 million of the upfront and milestone payments that were originally recorded as deferred revenue. Furthermore, the Company recognized $0.5 million of revenue from cost reimbursements for activities related to the preparation of a first in human trial. In the year ended

December 31, 2022, the Company recognized $0.3 million of the upfront payment that was originally recorded as deferred revenue.

Sublicense fees payable to certain licensors of technologies upon the receipt of the deferred upfront and milestone payments, were capitalized as a contract asset and will be amortized over the period in which the revenue from the triggering payment is recognized. As of December 31, 2024, there was no contract asset and no liability relating to sublicense payments. As of December 31, 2023 the contract asset and the liability relating to the sublicense payment was $2.0 million and there was no liability relating to sublicense payments.

Income taxes

12 Months Ended

Dec. 31, 2024

Income taxes

Income taxes

14. Income taxes

Income tax benefits during the year ended December 31, 2024 resulted from US federal income tax, partially offset by minimum tax obligations in Austria. Income tax expense during the years ended December 31, 2023 and December 31, 2022 resulted from US federal and state income tax as well as minimum tax obligations in Austria. During the years ended December 31, 2024, 2023 and 2022, the Company recorded no income tax benefits for the net operating losses incurred in each year, due to its uncertainty of realizing a benefit from those items. The Company's losses before income taxes were generated in the United States and Austria.

For financial reporting purposes, losses before income taxes for the years ended December 31, 2024, 2023 and 2022 consisted of the following (in thousands):


	Year ended December 31,
	2024		2023		2022
United States	$	(1,341)	$	1,710	$	(7,222)
Foreign (Austria)		(42,268)		(82,922)		(57,463)
Net loss before tax	$	(43,609)	$	(81,212)	$	(64,685)

The components of the consolidated income tax provision for the years ended December 31, 2024, 2023 and 2022 were as follows (in thousands):


	Year ended December 31,
	2024		2023		2022
Current
Federal	$	(107)	$	145	$	217
State		—		222		12
Foreign (Austria)		1		1		1
Total current tax (benefit) expense		(106)		368		230
Deferred
Federal		—		—		—
State		—		—		—
Foreign (Austria)		—		—		—
Total deferred tax expense		—		—		—

Total income tax (benefit) expense	$	(106)	$	368	$	230

The Company's worldwide effective tax rate for the years ended December 31, 2024, 2023 and 2022 was (0.2)%, 0.5% and 0.3%, respectively. The tax rate is affected by recurring items, such as tax rates in foreign jurisdictions and the relative amounts of income earned in those jurisdictions, which is expected to be fairly consistent in the near term. It is also affected by discrete items that may occur in any given year, but are not consistent from year to year. The following items had the most significant impact on the difference between the statutory U.S. federal income tax rate of 21% for the years ended December 31, 2024, 2023 and 2022 and the effective tax rate:


	Year ended December 31,
	2024			2023			2022
U.S. federal statutory income tax rate		(21.0)	%		(21.0)	%		(21.0)	%
State income taxes, net of federal benefit		—			(0.3)			—
Foreign tax rate differential⁽¹⁾		(2.0)			(2.7)			(4.0)
Not taxable government grants⁽²⁾		(4.9)			(6.8)			(3.8)
Stock-based compensation		0.8			0.6			0.5
Global intangible low-taxed income		—			2.3			1.4
Other		2.2			0.2			0.1
Change in deferred tax asset valuation allowance⁽³⁾		24.7			28.2			27.1
Effective income tax rate		(0.2)	%		0.5	%		0.3	%

⁽²⁾For the years ended December 31, 2024, 2023 and 2022, 4.9%, 6.8% and 3.8% increase, respectively, resulted from non-taxable research subsidies received from Austrian government agencies.

Components of the net deferred tax assets or liabilities as of the years ended December 31, 2024 and 2023 consisted of the following (in thousands):


	Year ended December 31,
	2024		2023
Deferred tax assets:
Net operating loss carryforwards	$	94,272	$	87,445
Capitalized R&D expenses		(0)		2,657
Credit carryforwards		1,787		1,265
Accrued expenses and other		182		317
Stock-based compensation		1,426		1,421
Operating lease liabilities		203		1,254
Total deferred tax assets		97,870		94,359
Valuation allowance		(93,382)		(89,309)
Total deferred tax assets		4,488		5,050

Deferred tax liabilities:
Accrued expenses and other		(4,281)		(3,774)
Fixed assets		(2)		(14)
Operating lease right of use asset		(205)		(1,262)
Total deferred tax liabilities		(4,488)		(5,050)

Net deferred tax assets	$	—	$	—

As of December 31, 2024, 2023 and 2022, the Company had Austrian net operating loss carryforwards of $400.9 million, $378.1 million and $275.3 million, respectively, that do not expire, however these carryforwards are limited to 75% of the taxable income in any one tax period. As of December 31, 2024, 2023 and 2022, the Company had federal net operating loss carryforwards that were generated after December 31, 2017 of $9.5 million, $2.2 million and $13.8 million, respectively, that do not expire, however these carryforwards are limited to 80% of the taxable income in any one tax period. In the year ended December 31, 2024 the Company filed for a method change which changed the net operating loss carry forwards for the year ended December 31, 2023 from $2.2 million to $10.5 million. The Company generated US taxable income in the current year and was able to offset 80% the taxable income utilizing net operating loss carryforwards which gave rise to current taxes during 2023. The federal net operating loss carryforward as of December 31, 2024 was $9.5 million, and US Federal net operating loss carryforward as of December 31, 2023 was $2.2 million. The Company has evaluated the positive and negative evidence bearing upon its ability to realize the deferred tax assets resulting from its net operating loss carryforwards. Management has considered the Company's history of cumulative net losses incurred since inception and the uncertainties related to the long period necessary to achieve profits from commercialization of any products and has concluded that it is more likely than not that the Company will not realize the benefits of its deferred tax assets. Accordingly, a full valuation allowance has been established against the deferred tax assets as of December 31, 2024, 2023 and 2022. According to a tax reform in Austria in 2022, the corporate income tax rate was reduced from 24.0% to 23.0% in 2024. The tax rate of 23.0% was used to determine deferred taxes and the valuation allowance for the Austrian business. Management reevaluates the positive and negative evidence at each reporting period.

The amount of the deferred tax asset considered realizable, however, could be adjusted if estimates of future taxable income during the carryforward period are reduced or increased or if objective negative evidence in the form of

losses is no longer present and additional weight may be given to subjective evidence. The tax years in which the tax carryforwards were generated may still be adjusted upon examination by the tax authorities.


	Year ended December 31,
	2024		2023		2022
Valuation allowance at beginning of period	$	(89,309)	$	(65,774)	$	(53,728)
Increases		(4,073)		(23,535)		(12,046)
Valuation allowance at end of period	$	(93,382)	$	(89,309)	$	(65,774)

On December 22, 2017, the United States enacted the Tax Cuts and Jobs Act (“Tax Reform Legislation” or “TCJA”). The Tax Reform Legislation introduced section 951A, a new tax on so-called “global intangible low-taxed income”. GILTI applies to income of a controlled foreign corporation (“CFC”) that is not otherwise subpart F income, and consists of the excess "tested income" over a 10% return on the CFC's “qualified business asset investment,” or “QBAI”. QBAI is the total tax basis of the CFC's depreciable, tangible property used in the production of tested income. The full amount of GILTI is included in taxable income. The GILTI inclusion is then reduced by 50% (reduced to 37.5% after 2025). However, that reduction in GILTI may be limited based on the level of U.S. taxable income. A limited allowance for foreign tax credits is allowed that would reduce the U.S. tax cost. GILTI foreign tax credits can only reduce U.S. taxes owed on GILTI and are not eligible for carryforward. The Company's Austrian subsidiary falls under the category of a CFC and due to the nature of its business model as a technology company, there may not be a material amount of tangible assets if this subsidiary starts to generate profits. GILTI taxation therefore may be applicable. The Company considered no GILTI inclusion for the year ended December 31, 2024, and previously estimated $8.8 million of GILTI inclusion for the tax year ended December 31, 2023. No U.S. tax on GILTI, net of research credits, for the year ended December 31, 2024, and U.S. tax on GILTI, net of research credits, of $0.4 million for the year ended December 31, 2023.

The Company files income tax returns in the U.S. federal jurisdiction as well as in New York. The tax years from 2018 to present remain open to examination by the jurisdictions in which the Company is subject to tax. There are currently no pending income tax examinations in the U.S. Furthermore, the Company files income tax returns in Austria. The tax years 2018 to present remain open to examination by the jurisdiction. There are currently no pending income tax examinations in Austria.

The Company evaluates tax positions for recognition using a more likely than not recognition threshold, and those tax positions eligible for recognition are measured as the largest amount of tax benefit that is greater than 50% likely of being realized upon the effective settlement with a taxing authority that has full knowledge of all relevant information. As of December 31, 2024 and 2023, the Company had no unrecognized income tax benefits that would affect the Company’s effective tax rate if recognized.

- Definition

The entire disclosure for income tax.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 231
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482663/740-10-55-231

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12C
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12C

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12B

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 270
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477891/740-270-50-1

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 6.I.5.Q1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479360/740-10-S99-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-13

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/740/tableOfContent

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-14

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-21

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 17
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-17

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479360/740-10-S99-2

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482603/740-30-50-2

+ Details

Summary of significant accounting policies (Tables)

12 Months Ended

Dec. 31, 2024

Summary of significant accounting policies

Schedule of estimated useful life of each asset


		Estimated useful life
Leasehold improvements		shorter of useful life or term of lease
Laboratory equipment		2 - 10 years
Furniture and fixtures		2 - 10 years
Computer equipment and software		2 - 4 years

Leases - Lease costs (Details) - USD ($) $ in Thousands	12 Months Ended
Leases - Lease costs (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Leases
Net lease expenses	$ 1,695	$ 1,589	$ 1,738
Research and development expenses
Leases
Operating lease expenses	1,374	1,347	1,430
Finance lease amortization expenses			89
General and administrative expense
Leases
Operating lease expenses	$ 321	$ 242	219
Interest expenses
Leases
Interest on finance lease liabilities			$ 0

Collaboration and Licensing Agreements (Details) $ in Millions	1 Months Ended		3 Months Ended		12 Months Ended
	Oct. 31, 2022 USD ($)	Jun. 30, 2018 USD ($) item	Jun. 30, 2024 USD ($)	Mar. 31, 2023 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Collaboration and Licensing Agreements
Collaborative arrangement revenue from cost reimbursements for preparation of first human trial					$ 0.1
Gilead Collaboration and License Agreement
Collaboration and Licensing Agreements
Number of preclinical research programs \| item		2
Upfront payment received		$ 10.0
Program initiation fee		$ 15.0
Payment term (in days)		60 days
Milestone payment received		$ 13.0
Deferred income					$ 5.5
Deferred revenues						$ 7.5
Percentage of upfront payment included in deferred revenue expected to be recognized in 2025					87.00%
Percentage of upfront payment included in deferred revenue expected to be recognized in 2026					13.00%
Revenue recognized from milestone payments					$ 6.7	7.1	$ 3.7
Revenue recognized from cost reimbursements for research and development services					0.8	1.4	5.2
Revenue recognized from milestone payments for milestones achieved							5.0
Contract asset relating to the sublicense payment					0.2	0.1
Contract liability relating to sublicense payment					0.0	0.0
HBV program \| Development Milestones
Collaboration and Licensing Agreements
Total milestone amount		140.0
HBV program \| Commercial Milestones
Collaboration and Licensing Agreements
Total milestone amount		50.0
HIV program \| Development Milestones
Collaboration and Licensing Agreements
Program completion fee		10.0
HIV program \| Development Milestones \| Maximum
Collaboration and Licensing Agreements
Total milestone amount		172.5
HIV program \| Commercial Milestones
Collaboration and Licensing Agreements
Total milestone amount		$ 65.0
Roche collaboration agreement
Collaboration and Licensing Agreements
Upfront payment received	$ 25.0
Milestone payment received			$ 10.0	$ 10.0
Deferred income					0.0
Deferred revenues						26.8
Revenue recognized from milestone payments					36.3
Contract asset relating to the sublicense payment					0.0	2.0
Revenue recognized from upfront payment						11.1	$ 0.3
Revenue recognized from cost reimbursements						0.5
Contract liability relating to sublicense payment					$ 0.0	$ 0.0

Insider Trading Policies and Procedures	12 Months Ended
Insider Trading Policies and Procedures	Dec. 31, 2024
Insider Trading Policies and Procedures [Line Items]
Insider Trading Policies and Procedures Adopted	true

Income taxes - Components of the net deferred tax assets or liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Deferred tax assets:
Net operating loss carryforwards	$ 94,272	$ 87,445
Capitalized R&D expenses	0	2,657
Credit carryforwards	1,787	1,265
Accrued expenses and other	182	317
Stock-based compensation	1,426	1,421
Operating lease liabilities	203	1,254
Total deferred tax assets	97,870	94,359
Valuation allowance	(93,382)	(89,309)	$ (65,774)	$ (53,728)
Total deferred tax assets	4,488	5,050
Deferred tax liabilities:
Accrued expenses and other	(4,281)	(3,774)
Fixed assets	(2)	(14)
Operating lease right of use asset	(205)	(1,262)
Total deferred tax liabilities	$ (4,488)	$ (5,050)

Nature of the business and organization

12 Months Ended

Dec. 31, 2024

Nature of the business and organization

Nature of the business and organization

1. Nature of the business and organization

HOOKIPA Pharma Inc. (“HOOKIPA” or the “Company”) is a clinical stage biopharmaceutical company developing a new class of immunotherapeutics based on its proprietary arenavirus platform that is designed to reprogram the body’s immune system.

The Company was incorporated under the name of HOOKIPA Biotech, Inc. under the laws of the State of Delaware in February 2017 as a fully-owned subsidiary of Hookipa Biotech AG. In June 2018, the Company changed its name from Hookipa Biotech, Inc. to HOOKIPA Pharma Inc. and in order to effectuate the change of the jurisdiction of incorporation, the Company acquired all of the shares of Hookipa Biotech AG, now Hookipa Biotech GmbH. HOOKIPA is headquartered in New York, with European research and preclinical development operations headquartered in Vienna, Austria. In April 2019, the Company closed its initial public offering (“IPO”) and its common stock is currently trading on the Nasdaq Capital Market under the ticker symbol “HOOK”.

The Company is subject to risks and uncertainties common to early-stage companies in the biotechnology industry, including, but not limited to, development by competitors of new technological innovations, dependence on key personnel, protection of proprietary technology, compliance with government regulations, the ability to establish clinical- and commercial-scale manufacturing processes and the ability to secure additional capital to fund operations. Product candidates currently under development will require significant additional research and development efforts, including extensive preclinical and clinical testing and regulatory approval prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel and infrastructure and extensive compliance-reporting capabilities and may not ultimately lead to a marketing approval and commercialization of a product. Even if the Company’s drug development efforts are successful, it is uncertain if and when the Company will realize significant revenue from product sales.

Subsequent events (Details)	Jan. 02, 2025 USD ($)
Poolbeg Pharma Plc \| Subsequent event
Subsequent events
Professional Fees	$ 1,300,000

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($)
$ in Thousands

12 Months Ended

Dec. 31, 2024

Dec. 31, 2023

Dec. 31, 2022

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS

Revenue from collaboration and licensing

$ 43,946

$ 20,129

$ 14,249

Revenue from Contract with Customer, Product and Service [Extensible List]

hook:CollaborationAndLicensingMember

Operating expenses:

Research and development

$ (68,507)

$ (86,424)

$ (68,645)

General and administrative

(20,226)

(18,633)

(18,759)

Restructuring

(2,664)

Impairment

(4,004)

(12,766)

Total operating expenses

(95,401)

(117,823)

(87,404)

Loss from operations

(51,455)

(97,694)

(73,155)

Other income (expense):

Grant income

7,396

11,193

7,916

Interest income

3,701

5,293

1,633

Interest expense

(2)

(317)

(687)

Other (expense) income, net

(3,249)

313

(392)

Total other income, net

7,846

16,482

8,470

Net loss before tax

(43,609)

(81,212)

(64,685)

Income tax expense

106

(368)

(230)

Net loss

(43,503)

(81,580)

(64,915)

Other comprehensive loss:

Foreign currency translation (loss) gain, net of tax

2,846

(777)

(2,376)

Comprehensive loss

$ (40,657)

$ (82,357)

$ (67,291)

Net loss per share - basic

^[1]

$ (3.47)

$ (8.63)

$ (9.91)

Net loss per share - diluted

^[1]

$ (3.47)

$ (8.63)

$ (9.91)

[1]	Share and per share amounts have been restated to reflect the one-for-ten reverse stock split effected in July 2024 on a retroactive basis for all periods presented.

Accrued expenses and other current liabilities (Tables)

12 Months Ended

Dec. 31, 2024

Accrued expenses and other current liabilities

Schedule of accrued expenses and other current liabilities

Accrued expenses and other current liabilities consisted of the following (in thousands):


	December 31,		December 31,
	2024		2023
Salaries and bonuses		4,193		5,665
Social security contributions		259		340
Unearned grant income		—		52
Accrued external research and development expenses		1,845		4,594
Accrued external general and administration expenses		2,921		292
Accrued for property and equipment acquisitions		—		14
Accrued for restructuring expenses		842		—
Income taxes		—		367
Other accruals and liabilities		592		777
	$	10,652	$	12,101

Property, plant and equipment, net (Tables)

12 Months Ended

Dec. 31, 2024

Property, plant and equipment, net and assets held for sale

Schedule of property, plant and equipment, net

Property, plant and equipment, net consisted of the following (in thousands):


	December 31,		December 31,
	2024		2023
Land	$	—	$	2,025
Leasehold improvements		3,095		3,300
Construction in progress		8		212
Laboratory equipment		—		8,722
Furniture and fixtures		601		654
Computer equipment and software		2,361		2,652
Property and equipment, gross		6,065		17,565
Less: Accumulated depreciation		(5,886)		(9,823)
Property and equipment, net	$	179	$	7,742

Schedule of classified as held for sale


	Balance as of		Additions to Assets				Balance as of
Assets	December 31, 2023		Held for Sale		Assets Sold		December 31, 2024
Land	$	—	$	1,895	$	—	$	1,895
Laboratory equipment		—		321		—		321
Total	$	—					$	2,216

Summary of significant accounting policies - Property and equipment (Details)	Dec. 31, 2024
Laboratory equipment \| Minimum
Property, plant and equipment, net and assets held for sale
Estimated useful life (in years)	2 years
Laboratory equipment \| Maximum
Property, plant and equipment, net and assets held for sale
Estimated useful life (in years)	10 years
Furniture and fixtures \| Minimum
Property, plant and equipment, net and assets held for sale
Estimated useful life (in years)	2 years
Furniture and fixtures \| Maximum
Property, plant and equipment, net and assets held for sale
Estimated useful life (in years)	10 years
Computer equipment and software \| Minimum
Property, plant and equipment, net and assets held for sale
Estimated useful life (in years)	2 years
Computer equipment and software \| Maximum
Property, plant and equipment, net and assets held for sale
Estimated useful life (in years)	4 years

Impairment (Tables)

12 Months Ended

Dec. 31, 2024

Restructuring

Schedule of restructuring charges


	Year ended December 31,
	2024		2023		2022
Non-cash impairment charges
Asset write-offs	$	(4,004)	$	(12,766)	$	—
Total non-cash impairment charges	$	(4,004)	$	(12,766)	$	—

Income taxes - Components of the consolidated income tax provision (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Current
Federal	$ (107)	$ 145	$ 217
State		222	12
Foreign (Austria)	1	1	1
Total current tax expense	(106)	368	230
Deferred
Total income tax expense	$ (106)	$ 368	$ 230

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

+ Details

Fair Value of Financial Assets (Tables)

12 Months Ended

Dec. 31, 2024

Fair Value of Financial Assets

Schedule of financial assets measured at fair value on a recurring basis


	Fair Value Measurement at December 31, 2024
	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	13,200	$	—	$	—	$	13,200
Assets held for sale		—		—		2,216		2,216
Total	$	13,200	$	—	$	2,216	$	15,416


	Fair Value Measurement at December 31, 2023
	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	91,084	$	—	$	—	$	91,084
Total	$	91,084	$	—	$	—	$	91,084

Restructuring (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended	12 Months Ended
Restructuring (Details) - USD ($) $ in Thousands	Nov. 18, 2024	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2024
Restructuring
Reduction if workforce (in percent)	80.00%		20.00%		30.00%
Cash restructuring charges
Severance and other personnel costs					$ 2,067
Professional fees and other related charges					597
Total		$ 500	$ 900	$ 1,300	$ 2,664