0001558370-22-013174 | 10-Q | XBRL Viewer

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Document and Entity Information - shares	6 Months Ended
Document and Entity Information - shares	Jun. 30, 2022	Aug. 03, 2022
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2022
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
Trading Symbol	HOOK
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	true
Entity Shell Company	false
Entity Central Index Key	0001760542
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q2
Amendment Flag	false
Common stock
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		51,654,530
Class A common stock
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		3,049,998

CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 117,918	$ 65,921
Restricted cash	523	566
Accounts receivable	1,187	6,895
Receivable research incentives	16,453	14,271
Prepaid expenses and other current assets	12,996	14,482
Total current assets	149,077	102,135
Non-current assets:
Restricted cash	418	425
Property, plant and equipment, net	16,952	16,352
Operating lease right of use assets	4,670	5,673
Finance lease right of use assets	0	90
Other non-current assets	1,095	1,370
Total non-current assets	23,135	23,910
Total assets	172,212	126,045
Current liabilities
Accounts payable	5,637	8,762
Deferred revenues	9,828	5,538
Operating lease liabilities, current	1,647	1,682
Accrued expenses and other current liabilities	8,689	8,880
Loans payable, current	1,423	2,792
Total current liabilities	27,224	27,654
Non-current liabilities
Loans payable, non-current	819	2,219
Operating lease liabilities, non-current	2,988	3,911
Deferred revenues, non-current	6,981	21
Other non-current liabilities	2,246	2,648
Total non-current liabilities	13,034	8,799
Total liabilities	40,258	36,453
Commitments and contingencies (Note 12)
Stockholders' equity:
Preferred stock, $0.0001 par value; 10,000,000 shares authorized at June 30, 2022 and December 31, 2021, respectively; Series A convertible preferred stock, 2,978 shares designated, 1,697 shares outstanding at June 30, 2022 and December 31, 2021, respectively; Series A-1 convertible preferred stock, 15,800 shares and no shares designated, 15,800 shares and no shares outstanding at June 30, 2022 and December 31, 2021, respectively	0	0
Additional paid-in capital	395,307	317,135
Accumulated other comprehensive loss	(6,268)	(4,780)
Accumulated deficit	(257,090)	(222,766)
Total stockholders' equity	131,954	89,592
Total liabilities and stockholders' equity	172,212	126,045
Common stock
Stockholders' equity:
Common stock	5	3
Class A common stock
Stockholders' equity:
Common stock	$ 0	$ 0

CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED) (Parenthetical) - $ / shares	Jun. 30, 2022	Dec. 31, 2021
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	10,000,000	10,000,000
Series A Convertible Preferred Stock
Preferred stock shares Designated	2,978	2,978
Preferred stock, shares outstanding	1,697	1,697
Series A -1 Convertible Preferred Stock
Preferred stock shares Designated	15,800	0
Preferred stock, shares outstanding	15,800	0
Common stock
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized	200,000,000	100,000,000
Common stock, shares issued	50,884,796	27,383,483
Common stock, shares outstanding	50,884,796	27,383,483
Class A common stock
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized	3,900,000	3,900,000
Common stock, shares issued	3,819,732	3,819,732
Common stock, shares outstanding	3,819,732	3,819,732

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (UNAUDITED)
Revenue from collaboration and licensing	$ 2,746	$ 5,378	$ 4,191	$ 10,679
Revenue from Contract with Customer, Product and Service [Extensible List]	hook:CollaborationAndLicensingMember	hook:CollaborationAndLicensingMember	hook:CollaborationAndLicensingMember	hook:CollaborationAndLicensingMember
Operating expenses:
Research and development	$ (16,147)	$ (19,572)	$ (32,767)	$ (39,736)
General and administrative	(5,026)	(5,095)	(9,998)	(9,404)
Total operating expenses	(21,173)	(24,667)	(42,765)	(49,140)
Loss from operations	(18,427)	(19,289)	(38,574)	(38,461)
Other income (expense):
Grant income	1,958	2,505	3,845	4,709
Interest income	182	7	189	14
Interest expense	(231)	(218)	(474)	(437)
Other income and (expenses), net	163	(158)	691	(216)
Total other income, net	2,072	2,136	4,251	4,070
Net loss before tax	(16,355)	(17,153)	(34,323)	(34,391)
Income tax expense	(1)	0	(1)	0
Net loss	(16,356)	(17,153)	(34,324)	(34,391)
Other comprehensive loss:
Foreign currency translation gain (loss), net of tax	(1,001)	293	(1,488)	(183)
Comprehensive loss	$ (17,357)	$ (16,860)	$ (35,812)	$ (34,574)
Net loss per share - basic	$ (0.23)	$ (0.52)	$ (0.58)	$ (1.05)
Net loss per share - diluted	$ (0.23)	$ (0.52)	$ (0.58)	$ (1.05)

CONDENSED CONSOLIDATED STATEMENTS OF CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY (UNAUDITED) - USD ($) $ in Thousands	Convertible Preferred Stock Series A-1 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	Additional Paid-In Capital Series A-1 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	Public offering	Stock Purchase Agreement	Total
Balance at the beginning of the period at Dec. 31, 2020		$ 0			$ 3	$ 0				$ 309,288	$ (6,067)	$ (147,101)				$ 156,123
Balance at the beginning of the period (in shares) at Dec. 31, 2020		2,978			25,948,712	3,819,732
Increase (Decrease) in Stockholders' Equity
Issuance of common stock upon exercise of stock options					$ 0					125						125
Issuance of common stock upon exercise of stock options (in shares)					33,806
Vesting of restricted stock					$ 0					0
Vesting of restricted stock (in shares)					12,140
Foreign currency translation adjustment, net of tax											(476)					(476)
Stock-based compensation expense										1,521						1,521
Net loss												(17,238)				(17,238)
Balance at the end of the period at Mar. 31, 2021		$ 0			$ 3	$ 0				310,934	(6,543)	(164,339)				140,055
Balance at the end of the period (in shares) at Mar. 31, 2021		2,978			25,994,658	3,819,732
Balance at the beginning of the period at Dec. 31, 2020		$ 0			$ 3	$ 0				309,288	(6,067)	(147,101)				156,123
Balance at the beginning of the period (in shares) at Dec. 31, 2020		2,978			25,948,712	3,819,732
Increase (Decrease) in Stockholders' Equity
Foreign currency translation adjustment, net of tax																(183)
Net loss																(34,391)
Balance at the end of the period at Jun. 30, 2021		$ 0			$ 3	$ 0				313,673	(6,250)	(181,492)				125,934
Balance at the end of the period (in shares) at Jun. 30, 2021		2,978			26,051,846	3,819,732
Balance at the beginning of the period at Dec. 31, 2020		$ 0			$ 3	$ 0				309,288	(6,067)	(147,101)				156,123
Balance at the beginning of the period (in shares) at Dec. 31, 2020		2,978			25,948,712	3,819,732
Increase (Decrease) in Stockholders' Equity
Net loss																(75,700)
Balance at the end of the period at Dec. 31, 2021		$ 0			$ 3	$ 0				317,135	(4,780)	(222,766)				89,592
Balance at the end of the period (in shares) at Dec. 31, 2021		1,697			27,383,483	3,819,732
Balance at the beginning of the period at Mar. 31, 2021		$ 0			$ 3	$ 0				310,934	(6,543)	(164,339)				140,055
Balance at the beginning of the period (in shares) at Mar. 31, 2021		2,978			25,994,658	3,819,732
Increase (Decrease) in Stockholders' Equity
Issuance of common stock upon exercise of stock options					$ 0					112						112
Issuance of common stock upon exercise of stock options (in shares)					45,681
Vesting of restricted stock					$ 0					0
Vesting of restricted stock (in shares)					11,507
Foreign currency translation adjustment, net of tax											293					293
Stock-based compensation expense										2,627						2,627
Net loss												(17,153)				(17,153)
Balance at the end of the period at Jun. 30, 2021		$ 0			$ 3	$ 0				313,673	(6,250)	(181,492)				125,934
Balance at the end of the period (in shares) at Jun. 30, 2021		2,978			26,051,846	3,819,732
Balance at the beginning of the period at Dec. 31, 2021		$ 0			$ 3	$ 0				317,135	(4,780)	(222,766)				89,592
Balance at the beginning of the period (in shares) at Dec. 31, 2021		1,697			27,383,483	3,819,732
Increase (Decrease) in Stockholders' Equity
Issuance of stock	$ 0		$ 2	$ 0			$ 29,625	$ 40,685	$ 5,000				$ 29,625	$ 40,687	$ 5,000
Issuance of stock (in shares)	15,800		21,700,000	1,666,666
Issuance of common stock upon exercise of stock options					$ 0					1						1
Issuance of common stock upon exercise of stock options (in shares)					10,034
Foreign currency translation adjustment, net of tax											(487)					(487)
Vesting of equity grants					$ 0					0
Vesting of equity grants (in shares)					112,551
ATM costs										(142)						(142)
Stock-based compensation expense										1,621						1,621
Net loss												(17,968)				(17,968)
Balance at the end of the period at Mar. 31, 2022		$ 0			$ 5	$ 0				393,925	(5,267)	(240,734)				147,929
Balance at the end of the period (in shares) at Mar. 31, 2022		17,497			50,872,734	3,819,732
Balance at the beginning of the period at Dec. 31, 2021		$ 0			$ 3	$ 0				317,135	(4,780)	(222,766)				$ 89,592
Balance at the beginning of the period (in shares) at Dec. 31, 2021		1,697			27,383,483	3,819,732
Increase (Decrease) in Stockholders' Equity
Issuance of common stock upon exercise of stock options (in shares)																22,096
Foreign currency translation adjustment, net of tax																$ (1,488)
Net loss																(34,324)
Balance at the end of the period at Jun. 30, 2022		$ 0			$ 5	$ 0				395,307	(6,268)	(257,090)				131,954
Balance at the end of the period (in shares) at Jun. 30, 2022		17,497			50,884,796	3,819,732
Balance at the beginning of the period at Mar. 31, 2022		$ 0			$ 5	$ 0				393,925	(5,267)	(240,734)				147,929
Balance at the beginning of the period (in shares) at Mar. 31, 2022		17,497			50,872,734	3,819,732
Increase (Decrease) in Stockholders' Equity
Issuance of common stock upon exercise of stock options					$ 0					1						1
Issuance of common stock upon exercise of stock options (in shares)					12,062
Foreign currency translation adjustment, net of tax											(1,001)					(1,001)
Stock-based compensation expense										1,381						1,381
Net loss												(16,356)				(16,356)
Balance at the end of the period at Jun. 30, 2022		$ 0			$ 5	$ 0				$ 395,307	$ (6,268)	$ (257,090)				$ 131,954
Balance at the end of the period (in shares) at Jun. 30, 2022		17,497			50,884,796	3,819,732

CONDENSED CONSOLIDATED STATEMENTS OF CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY (UNAUDITED) (Parenthetical) $ in Thousands	3 Months Ended
	Mar. 31, 2022 USD ($) $ / shares
Series A-1 convertible preferred stock
Share price (in USD per share) \| $ / shares	$ 2,000
Issuance costs \| $	$ 1,975
Common stock \| Public offering
Share price (in USD per share) \| $ / shares	$ 2.00
Issuance costs \| $	$ 2,713
Common stock \| Stock Purchase Agreement
Share price (in USD per share) \| $ / shares	$ 3.00
Issuance costs \| $	$ 0

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Operating activities:
Net loss	$ (34,324)	$ (34,391)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	3,002	4,148
Depreciation and amortization expense	1,938	2,321
Other non-cash items	156	33
Changes in operating assets and liabilities:
Accounts receivable	5,267	444
Receivable research incentives	(3,399)	(1,357)
Prepaid expenses and other current assets	523	(12,323)
Other non-current assets	177	(923)
Accounts payable	(1,833)	457
Deferred revenues	12,193	(1,364)
Operating lease liabilities	(864)	(1,006)
Accrued expenses and other liabilities	299	11,008
Other non-current liabilities	239	(2,176)
Net cash provided by (used in) operating activities	(16,626)	(35,129)
Investing activities:
Purchases of property and equipment	(3,460)	(4,954)
Net cash used in investing activities	(3,460)	(4,954)
Financing activities:
Payments related to finance leases	(22)	(51)
Proceeds from issuance of convertible preferred stock, net of issuance costs	29,625
Proceeds from issuance of common stock, net of issuance costs	45,689	237
Repayments of borrowings	(2,952)	0
Net cash provided by financing activities	72,340	186
Net increase (decrease) in cash, cash equivalents and restricted cash	52,254	(39,897)
Cash, cash equivalents and restricted cash at beginning of period	66,912	143,177
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(307)	(327)
Cash, cash equivalents and restricted cash at end of period	118,859	102,953
Supplemental disclosure of cash flow information:
Cash paid for interest	(22)	(24)
Cash paid for income taxes	(1)	0
Supplemental disclosure of non-cash financing activities:
Property and equipment additions in accounts payable and accrued expenses	(145)	(3,426)
Lease assets obtained in exchange for new operating lease liabilities	$ 234
Lease assets derecognized upon lease cancellation		$ 16

Nature of the business and organization

6 Months Ended

Jun. 30, 2022

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 started trading on the Nasdaq Global Select 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.

Summary of significant accounting policies

6 Months Ended

Jun. 30, 2022

Summary of significant accounting policies

Summary of significant accounting policies

2. Summary of significant accounting policies

Basis of presentation

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

The consolidated balance sheet as of December 31, 2021 was derived from audited financial statements but does not include all disclosures required by GAAP. The accompanying condensed consolidated balance sheet as of June 30, 2022, the condensed consolidated statements of operations, and comprehensive loss for the three and six months ended June 30, 2022 and 2021, the condensed consolidated statement of convertible preferred stock and stockholders’ equity for the three and six months ended June 30, 2022 and 2021 and the condensed consolidated statements of cash flows for the six months ended June 30, 2022 and 2021 are unaudited.

The unaudited interim condensed consolidated financial statements have been prepared on the same basis as the audited annual consolidated financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for the fair statement for interim reporting. Certain information and footnote disclosures typically included in annual financial statements prepared in accordance with GAAP have been condensed or omitted. Accordingly, these unaudited interim condensed consolidated financial statements should be read in conjunction with the Company’s audited financial statements for the year ended December 31, 2021 included in the Company’s Annual Report on Form 10-K, filed with the Securities and Exchange Commission. The results for any interim period are not necessarily indicative of results for any future period. Certain previous year amounts have been reclassified to conform to the current year presentation.

Going concern

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 June 30, 2022, 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 $34.3 million for the six months ended June 30, 2022 and $75.7 million for the year ended December 31, 2021. As of June 30, 2022, the Company had an accumulated deficit of $257.1 million. The Company expects to continue to generate operating losses in the foreseeable future. As of August 11, 2022, the filing date of this Quarterly Report on Form 10-Q, the Company expects that its cash and cash equivalents will be sufficient to fund its operating expenses, capital expenditure requirements and debt service payments through at least 12 months from the issuance date of the condensed consolidated financial statements.

The Company will seek additional funding in order to reach its development and commercialization objectives. The Company may seek funds through further equity financings, debt financings, collaborations, strategic alliances and marketing, distribution or licensing arrangements. The Company may not be able to obtain financing on acceptable terms, or at all, and the Company may not be able to enter into collaborations or other arrangements. The terms of any financing may adversely affect the holdings or the rights of the Company’s stockholders. If the Company is unable to obtain funding, the Company could be forced to delay, reduce or eliminate some or all of its research and development programs, product portfolio expansion or commercialization efforts, which could adversely affect its business prospects.

The accompanying condensed 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 condensed 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 be necessary if the Company is unable to continue as a going concern.

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 condensed 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 and the valuation of current and non-current loans payable. 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.

On March 11, 2020 the World Health Organization designated COVID-19 as a global pandemic. The Company believes the extent of the COVID-19 pandemic’s impact on the Company’s business, results of operations and financial condition has been, and will continue to be driven by many factors, most of which are beyond the Company’s control and ability to forecast. Because of these uncertainties, the Company cannot estimate how long or to what extent the pandemic will impact its operations. The Company’s accounting estimates and assumptions may change over time in response to COVID-19 and the change could be material in future periods. As of the date of issuance of these unaudited condensed 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.

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.

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 three and six months ended June 30, 2022 and June 30, 2021 the net proceeds from the Company’s offerings have been deposited in bank accounts with 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 June 30, 2022 and December 31, 2021, the Company’s cash and cash equivalents included smaller amounts of cash balances held in accounts with 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 June 30, 2022 and December 31, 2021, Gilead Sciences, Inc. (“Gilead”) accounted for the majority of the accounts receivable balance. For the six months ended June 30, 2022 and June 30, 2021 Gilead accounted for the majority of the Company’s revenues. Other customers accounted for less than 10.0% of accounts receivable or net sales. 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.

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 June 30, 2022 and December 31, 2021, cash equivalents consisted of money market funds.

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 4).

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 a 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 Accounting Standards Codification (“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.

Revenue recognition from contracts with customers

The Company entered into a collaboration and license agreement (as amended and restated, the “Gilead Agreement”) with Gilead whereby 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 Company signed an amended and restated collaboration agreement (the “Restated Collaboration Agreement”), which revised the terms only for the HIV program, whereby the Company will take 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 Collaboration Agreement added an additional performance obligation to perform research and development work for the HIV program to the Company. The licenses do not represent distinct performance obligations, because they cannot be used without the research and development services. Payments to the Company under this 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.

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 obligations under the collaboration and licensing arrangement, represent separate or one or more combined performance obligations, the allocation of the transaction price to identified performance obligations, and the determination of when milestone payments are probable of being received.

Upfront payment and program initiation payment

The non-refundable upfront-payment received by the Company upon signing of the Gilead 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 by the Company upon signing of an amendment and restatement of the Gilead 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.

Reimbursement for services

Under the Gilead Agreement, the Company incurs employee expenses as well as external costs for research and manufacturing activities presented as operating expenses or prepaid expenses. Based on the nature of the Company's responsibilities under the collaboration arrangement, 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 Agreement includes 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. The Company will continue to assess the probability of significant reversals for any amounts that become likely to be realized prior to recognizing the variable consideration associated with these payments within the transaction price.

Sales-based milestones and royalty payments

The Gilead Agreement also includes 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 agreement. 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.

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 2021, the FASB issued ASU 2021-10, Government Assistance (Topic 832): Disclosures by Business Entities about Government Assistance, which requires business entities to provide certain disclosures when they have received government assistance and when they use a grant or contribution accounting model by analogy to other accounting guidance (e.g., a grant model under IAS 20, Accounting for Government Grants and Disclosure of Government Assistance, or ASC 958-605, Not-For-Profit Entities — Revenue Recognition). Topic 832 requires the annual disclosures about transactions with a government that are accounted for by applying a grant or contribution accounting model by analogy of information about the nature of the transactions and the related accounting policy used to account for the transactions, the line items on the balance sheet and income statement that are affected by the transactions, and the amounts applicable to each financial statement line item, significant terms and conditions of the transactions, including commitments and contingencies. The guidance in ASU 2021-10 is effective for all entities for fiscal years beginning after December 15, 2021. The Company has already provided all relevant disclosures regarding Government Assistance on its consolidated financial statements prior adoption of ASU 2021-10. Therefore, the early adoption of this standard as of January 1, 2022 on a prospective basis did not have a material impact on the Company’s consolidated financial statements.

Recently Issued Accounting Pronouncements

In August 2020, the FASB issued ASU 2020-06, Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging – Contracts in Entity’s Own Equity (Subtopic 815-40). The ASU provides guidance that simplified the accounting for certain financial instruments with characteristics of liabilities and equity. The new guidance reduced the number of accounting models for convertible debt and convertible preferred stock instruments and made certain disclosure amendments intended to improve the information provided to users. The guidance also amended the derivative guidance for the “own stock” scope exception, which exempts qualifying instruments from being accounted for as derivatives if certain criteria are met. Finally, the standard changed the way certain convertible instruments are treated when calculating earnings per share. This guidance is effective for fiscal years beginning after December 15, 2023, including interim periods within those fiscal years, with early adoption permitted. The Company is currently assessing the impact that this guidance will have on its consolidated financial statements.

Collaboration and Licensing Agreements

6 Months Ended

Jun. 30, 2022

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 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 an 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 original Gilead 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 amended and restated agreement, 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, inclusive of the $10.0 million option exercise payment, for the HIV program upon Gilead’s exercise of such option. The commercial milestones amount to a total of $50.0 million for the HBV program, and $65.0 million for the HIV program upon Gilead’s exercise of the option. Additionally, Gilead is obligated to pay royalties on net sales for each program. Payments from Gilead generally have a 60 days payment term.

The $10.0 million upfront payment, the $15.0 million initiation fee and $8.0 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 June 30, 2022, $16.2 million of such payments were still recorded as a liability in deferred revenues, current and non-current. As of December 31, 2021, $4.3 million of upfront and milestone payments were included as a liability in deferred revenues, current. Approximately 42% of deferred revenue is expected to be recognized as revenue in the remainder of 2022, 31% in 2023, 18% in 2024 and the remaining 9% in 2025.

As of June 30, 2022, $0.6 million of cost reimbursements for research and development services were recorded as a liability in deferred revenues. As of December 31, 2021, $1.2 million of cost reimbursements for research and development services were recorded as a liability in deferred revenues. Reimbursements for external costs are recognized as revenues in the period in which the services are provided and external costs are recognized.

In the three months ended June 30, 2022, the Company recognized $1.0 million of the milestone and initiation payments that were originally recorded as deferred revenue. Furthermore, the Company recognized $1.7 million revenue from cost reimbursements for research and development services, of which $0.5 million were initially recorded as deferred revenue in the consolidated balance sheet. In the three months ended June 30, 2021, the Company recognized $1.0 million of the upfront and milestone payments that were originally recorded as deferred revenue. Furthermore, the Company recognized $4.4 million revenue from cost reimbursements for research and development services, of which $0.4 million were initially recorded as deferred revenue in the consolidated balance sheet.

In the six months ended June 30, 2022, the Company recognized $1.6 million of the milestone and initiation payments that were originally recorded as deferred revenue. Furthermore, the Company recognized $2.5 million revenue from cost reimbursements for research and development services, of which $0.6 million were initially recorded as deferred revenue in the consolidated balance sheet. In the six months ended June 30, 2021, the Company recognized $1.7 million of the upfront and milestone payments that were originally recorded as deferred revenue. Furthermore, the Company recognized $9.0 million revenue from cost reimbursements for research and development services, of which $0.7 million were initially recorded as deferred revenue in the consolidated balance sheet.

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 June 30, 2022 and December 31, 2021, the contract asset relating to the sublicense payment was $0.3 million and $0.3 million, respectively.

Fair Value of Financial Assets

6 Months Ended

Jun. 30, 2022

Fair Value of Financial Assets

Fair Value of Financial Assets

4. 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 June 30, 2022 Using
	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	80,094	$	—	$	—	$	80,094
Total	$	80,094	$	—	$	—	$	80,094


	Fair Value Measurement at December 31, 2021 Using
	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	35,403	$	—	$	—	$	35,403
Total	$	35,403	$	—	$	—	$	35,403

During the six months ended June 30, 2022, 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 + Details

Property, plant and equipment, net

6 Months Ended

Jun. 30, 2022

Property, plant and equipment, net.

Property, plant and equipment, net

5. Property, plant and equipment, net

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


	June 30,		December 31,
	2022		2021

Land	$	1,917	$	2,072
Leasehold improvements		3,096		3,348
Construction in progress		9,413		7,746
Laboratory equipment		6,850		7,025
Furniture and fixtures		608		651
Computer equipment and software		1,772		1,876
Property and equipment, gross		23,656		22,718
Less: Accumulated depreciation		(6,704)		(6,366)
Property and equipment, net	$	16,952	$	16,352

Construction-in-progress as of June 30, 2022 and December 31, 2021 mainly related to investments in connection with the Company’s GMP manufacturing facility project.

Receivable research incentive

6 Months Ended

Jun. 30, 2022

Receivable research incentive

Receivable research incentive

6. 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.

As of June 30, 2022, the Company recognized receivables of $16.5 million from the research incentive program, which are reported in research incentive receivables in the Company’s condensed consolidated balance sheet. As of December 31, 2021, the receivables from the research incentive program were $14.3 million.

During the three months ended June 30, 2022 and 2021, the Company recorded $1.7 million and $2.3 million, respectively, of income related to the incentive program within the Company’s condensed consolidated statements of operations as part of the grant income.

During the six months ended June 30, 2022 and 2021, the Company recorded $3.4 million and $4.3 million, respectively, of income related to the incentive program within the Company’s condensed consolidated statements of operations as part of the grant income.

Accrued expenses and other current liabilities

6 Months Ended

Jun. 30, 2022

Accrued expenses and other current liabilities

Accrued expenses and other current liabilities

7. Accrued expenses and other current liabilities

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


	June 30,		December 31,
	2022		2021
Salaries and bonuses		3,667		4,754
Social security contributions		370		250
Unearned grant income (current)		411		693
Sublicense fees		—		304
Accrued external research and development expenses		2,954		2,165
Accrued external general and administration expenses		910		629
Accrued for property and equipment acquisitions		—		7
Finance lease liabilities		—		21
Other accruals and liabilities		377		57
	$	8,689	$	8,880

Loans payable

6 Months Ended

Jun. 30, 2022

Loans payable

Loans payable

8. Loans payable

As of June 30, 2022 and December 31, 2021, loans payable consisted of the following (in thousands):


	June 30,		December 31,
	2022		2021
Loans from FFG	$	2,793	$	6,074
Unamortized debt discount		(551)		(1,063)
Total loans payable, net	$	2,242	$	5,011

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. Amounts due under the FFG Loans bear interest at a rate of 0.75% per annum and mature at various dates between March 2023 and March 2024. Interest on amounts due under the loans is payable semi-annually in arrears, with all principal and remaining accrued interest due upon maturity.

The FFG Loans bear interest at rates that are below market rates of interest. The Company accounts 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 recognizes 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 is recognized as grant income over the term of the funding agreement.

A principal repayment of $3.0 million was made in the six months ended June 30, 2022. No principal repayment was made in the six months ended June 30, 2021.

As of June 30, 2022, the aggregate minimum future principal payments due in connection with the FFG Loans are summarized as follows (in thousands):


Payments Due by Calendar Year	Amount
2022 (remaining 6 months)		—
2023		1,684
2024		1,109
2025		—
2026		—
Thereafter		—
Total	$	2,793

Common stock, Class A common stock and convertible preferred stock

6 Months Ended

Jun. 30, 2022

Common stock, Class A common stock and convertible preferred stock

Common stock, Class A common stock and convertible preferred stock

9. 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. As of June 30, 2022, the Company was authorized to issue 200,000,000 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 and 15,800 of the 10,000,000 authorized shares of preferred stock as non-voting Series A-1 convertible preferred stock. As of June 30, 2022, the Company had 50,884,796 shares of common stock, 3,819,732 shares of Class A common stock, 1,697 shares of Series A convertible preferred stock and 15,800 shares of Series A-1 convertible preferred stock outstanding and issued.

On February 15, 2022, the Company entered into a Stock Purchase Agreement (the “Stock Purchase Agreement”) with Gilead, 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 1,666,666 shares of the Company’s common stock in exchange for $5.0 million in cash at a purchase price per share equal to $3.00. Pursuant to the terms of the Stock Purchase Agreement, the Company may require Gilead to purchase the balance of the $30.0 million of common stock, at the discretion of the Company, in one or two subsequent purchases at a price equal to the volume weighted average purchase price preceding such purchase, as defined in the Stock Purchase Agreement, plus, for the first subsequent purchase, which can be up to the full $30.0 million balance, a premium of 30%. 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. At June 30, 2022, this limitation would have prevented the Company from requesting that Gilead purchase the full $30.0 million balance of the investment commitment. The Company agreed to file a registration statement on Form S-3 to register for resale any additional shares of common stock issued to Gilead within four months from issuance.

On March 4, 2022, the Company closed a public offering of 21,700,000 shares of its common stock and of 15,800 shares of Series A-1 convertible preferred stock at a public offering price of $2.00 and $2,000.00 per share, respectively, for net proceeds of $70.2 million after deducting underwriting discounts and commissions and offering expenses including pro-rata ATM expenses.

The Company has two series of preferred stock authorized, issued and outstanding as of June 30, 2022: Series A convertible preferred stock and Series A-1 convertible preferred stock. Shares of Series A and Series A-1 convertible preferred stock may be independently converted into common stock. Holders of Series A and Series A-1 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 and Series A-1 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 one share of common stock at such holder's election. Each holder of Series A and Series A-1 convertible preferred stock has the right to convert each share of Series A and Series A-1 convertible preferred stock into 1,000 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 and Series A-1 preferred stock into shares of our 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 and Series A-1 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 our Series A and Series A-1 preferred stock will receive a payment equal to $0.001 per share of Series A and Series A-1 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.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496180-112644

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=123467817&loc=SL123496158-112644

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(e)(1))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

+ Details

Stock-based compensation

6 Months Ended

Jun. 30, 2022

Stock-based compensation

Stock-based compensation

10. Stock-based compensation

2018 Stock Option and Grant Plan

In June 2018, the 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 June 30, 2022, 927,115 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. 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 is 5,878,814 shares which shall be cumulatively increased each year by up to 4% of the then outstanding number of shares. 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. Option re-grants to non-executive directors generally vest on 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.

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:


	Three months ended June 30,				Six months ended June 30,
	2022		2021		2022		2021

Risk-free interest rate	2.96	%	1.07	%	2.87	%	1.07	%
Expected term (in years)	6.1		6.1		6.0		6.1
Expected volatility	84.8	%	85.5	%	84.9	%	85.5	%
Expected dividends	—	%	—	%	—	%	—	%

For the 2022 and 2021 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, 2022 (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, 2021	4,231,178	$	9.21	7.5	$	1,640
Granted	2,028,291		1.65
Exercised	(22,096)		0.10
Forfeited	(123,205)		8.78
Outstanding as of June 30, 2022	6,114,168	$	6.74	8.0	$	1,097

Options exercisable as of June 30, 2022	2,913,971	$	8.22	6.7	$	1,093
Options unvested as of June 30, 2022	3,200,197	$	5.38	9.1	$	4

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 June 30, 2022 and December 31, 2021, was $1.63 and $2.33, respectively.

Cash received from stock option exercise under share-based payment arrangements for the six months ended June 30, 2022 was $2 thousand. Cash received from stock option exercise under share-based payment arrangements for the six months ended June 30, 2021 was $237 thousand.

Common Stock Awards

In the three months ended March 31, 2022 the Company issued unrestricted shares of common stock to its executive team. The Company’s executive team agreed to convert a portion of their base salaries, for the six months ending June 30, 2022, for shares of the Company’s fully vested common stock having a value equal to their foregone salary, determined based on a value of $3.00 per share, resulting in the issuance of 112,551 shares of common stock. The total fair value of common stock awards issued during the three months ended March 31, 2022 was $0.2 million. The grant date fair value per share of common stock was $1.50 and was measured at the closing price of the common stock on the date of grant. Expenses were recorded immediately and are included in stock based compensation in the three months ended March 31, 2022. No unrestricted shares of common stock were issued in the three months ended June 30, 2022.

Stock-based compensation

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


	Three months ended June 30,				Six months ended June 30,
	2022		2021		2022		2021
Research and development expenses	$	522	$	1,145	$	1,140	$	1,769
General and administrative expenses		859		1,482		1,862		2,379
	$	1,381	$	2,627	$	3,002	$	4,148

Income taxes

6 Months Ended

Jun. 30, 2022

Income taxes

Income taxes

11. Income taxes

Income tax expense during the six months ended June 30, 2022 and 2021 resulted from minimum tax obligations. During the three and six months ended June 30, 2022 and 2021, the Company recorded no income tax benefits for the net operating losses incurred, 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. 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 its lack of commercialization of any products or generation of any revenue from product sales since inception 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 June 30, 2022 and December 31, 2021. Management reevaluates the positive and negative evidence at each reporting period.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 21
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32857-109319

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-URI http://asc.fasb.org/extlink&oid=122134291&loc=d3e330215-122817

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 17
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32809-109319

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I.5.Q1)
-URI http://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32705-109319

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6424409&loc=d3e44925-109338

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-URI http://asc.fasb.org/topic&trid=2144680

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6424122&loc=d3e41874-109331

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

+ Details

Commitments and contingencies

6 Months Ended

Jun. 30, 2022

Commitments and contingencies

Commitments and contingencies

12. Commitments and contingencies

Operating and Finance 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 is required to maintain a cash balance of $0.4 million to secure letters of credit associated with real estate leases. This amount was classified as non-current restricted cash in the Company’s condensed consolidated balance sheet as of June 30, 2022.

As of June 30, 2022 and December 31, 2021, the Company’s operating lease right-of-use assets were $4.7 million and $5.7 million, respectively, which are reported in operating lease right-of-use assets in the Company’s condensed consolidated balance sheets. As of June 30, 2022 the Company had no finance lease right-of-use assets, as of December 31, 2021, the Company’s finance lease right-of-use assets were $0.1 million, which are reported in finance lease right-of-use assets in the Company’s condensed consolidated balance sheets. As of June 30, 2022, the Company had outstanding operating lease obligations of $4.6 million, of which $1.6 million is reported in operating lease liabilities, current portion and $3.0 million is reported in operating lease liabilities, non-current portion in the Company’s condensed consolidated balance sheets. As of June 30, 2022, the Company had no outstanding finance lease obligations. As of December 31, 2021, the Company had outstanding operating lease obligations of $5.6 million, of which $1.7 million is reported in operating lease liabilities, current portion and $3.9 million is reported in operating lease liabilities, non-current portion in the Company’s condensed consolidated balance sheets. As of December 31, 2021, the Company had outstanding finance lease obligations of less than $0.1 million, which is reported in accrued expenses and other current liabilities in the Company’s condensed consolidated balance sheets. The Company’s weighted average discount rate and weighted average lease term remaining on operating lease liabilities is approximately 1.4% and 3.3 years, respectively.

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 June 30, 2022, the Company’s total non-cancellable obligations under contracts with CMOs, excluding embedded lease liabilities, were $8.5 million, of which $4.5 million relate to 2022 (remaining six months) deliverables, $4.0 million relate to 2023, and less than $0.1 million relate to 2024 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 three and six months ended June 30, 2022, the Company recorded $0.4 million and $0.7 million, respectively, in licensing fees related to intellectual property licenses as general and administrative expenses. These amounts are partly related to the upfront payment and milestone payments received by the Company under the Gilead Agreement. The amounts recognized as expenses have 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 condensed consolidated financial statements as of June 30, 2022 or December 31, 2021.

Legal proceedings

At each reporting date, the Company evaluates whether or not a potential loss amount or a potential range of loss is probable and reasonably estimable under the provisions of the authoritative guidance that addresses accounting for contingencies. The Company is currently a party to a patent proceeding opposing European Patent No. 3218504, which was granted to the University of Geneva in July 2020 and is exclusively licensed to the Company. While it is not feasible to predict the outcome of these matters with certainty, and some lawsuits, claims or proceedings may be disposed or decided unfavorably, the Company does not expect that the pending patent opposition, and any asserted or unasserted legal claims or proceedings, individually or in the aggregate, will have a material adverse effect on the Company. However, if, as a result of the current patent proceeding, the Company would lose all, or at least part, of the protection under the opposed patent, such loss could erode the Company’s competitive position and harm its business and ability to achieve profitability. The Company expenses the costs related to the pending and other such legal proceedings as incurred.

Net loss per share

6 Months Ended

Jun. 30, 2022

Net loss per share

Net loss per share

13. 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 per share amounts):


	Three months ended June 30,				Six months ended June 30,
	2022		2021		2022		2021
Numerator:
Net loss	$	(16,356)	$	(17,153)	$	(34,324)	$	(34,391)

Denominator:
Weighted-average common shares outstanding, basic and diluted		54,698,007		29,826,269		46,694,976		29,807,382
Weighted-average Series A convertible preferred shares outstanding, basic and diluted, presented as if converted into common stock⁽¹⁾		1,697,000		2,978,000		1,697,000		2,978,000
Weighted-average Series A-1 convertible preferred shares outstanding, basic and diluted, presented as if converted into common stock⁽¹⁾		15,800,000		—		10,300,552		—
Total number of shares used to calculate net loss per share, basic and diluted		72,195,007		32,804,269		58,692,528		32,785,382

Net loss per share, basic and diluted	$	(0.23)	$	(0.52)	$	(0.58)	$	(1.05)

⁽¹⁾ Series A and Series A-1 convertible preferred stock are participating securities that have substantially the same terms and features as the Company’s common stock. Series A and Series A-1 convertible preferred stock is therefore included in the weighted-average number of shares outstanding to calculate net loss per share, basic and diluted as if converted in

common stock. Each share of Series A and Series A-1 convertible preferred stock is independently convertible into 1,000 shares of common stock. 1,697,000 shares of the Company’s common stock are issuable upon conversion of Series A convertible preferred stock and 15,800,000 shares of the Company’s common stock are issuable upon conversion of Series A-1 convertible preferred stock (see Note 9).

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:


	Three and six months ended June 30,
	2022	2021
Options issued and outstanding	6,114,168	4,283,995
Unvested restricted stock units	—	20,053
Total	6,114,168	4,304,048

Summary of significant accounting policies (Policies)

6 Months Ended

Jun. 30, 2022

Summary of significant accounting policies

Basis of presentation

Going concern

Use of estimates

Deferred offering costs

Concentrations of credit risk and of significant suppliers

Cash equivalents

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 4).

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

Revenue recognition from contracts with customers

Upfront payment and program initiation payment

Reimbursement for services

Research and development milestones

Sales-based milestones and royalty payments

Cost to fulfill contracts

Recent accounting pronouncements

Adopted as of current period

Recently Issued Accounting Pronouncements

Summary of significant accounting policies (Tables)

6 Months Ended

Jun. 30, 2022

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

Fair Value of Financial Assets (Tables)

6 Months Ended

Jun. 30, 2022

Fair Value of Financial Assets

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


	Fair Value Measurement at June 30, 2022 Using
	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	80,094	$	—	$	—	$	80,094
Total	$	80,094	$	—	$	—	$	80,094


	Fair Value Measurement at December 31, 2021 Using
	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	35,403	$	—	$	—	$	35,403
Total	$	35,403	$	—	$	—	$	35,403

Property, plant and equipment, net (Tables)

6 Months Ended

Jun. 30, 2022

Property, plant and equipment, net.

Schedule of property, plant and equipment, net

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


	June 30,		December 31,
	2022		2021

Land	$	1,917	$	2,072
Leasehold improvements		3,096		3,348
Construction in progress		9,413		7,746
Laboratory equipment		6,850		7,025
Furniture and fixtures		608		651
Computer equipment and software		1,772		1,876
Property and equipment, gross		23,656		22,718
Less: Accumulated depreciation		(6,704)		(6,366)
Property and equipment, net	$	16,952	$	16,352

Accrued expenses and other current liabilities (Tables)

6 Months Ended

Jun. 30, 2022

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):


	June 30,		December 31,
	2022		2021
Salaries and bonuses		3,667		4,754
Social security contributions		370		250
Unearned grant income (current)		411		693
Sublicense fees		—		304
Accrued external research and development expenses		2,954		2,165
Accrued external general and administration expenses		910		629
Accrued for property and equipment acquisitions		—		7
Finance lease liabilities		—		21
Other accruals and liabilities		377		57
	$	8,689	$	8,880

Loans payable (Tables)

6 Months Ended

Jun. 30, 2022

Loans payable

Schedule of loans payable

As of June 30, 2022 and December 31, 2021, loans payable consisted of the following (in thousands):


	June 30,		December 31,
	2022		2021
Loans from FFG	$	2,793	$	6,074
Unamortized debt discount		(551)		(1,063)
Total loans payable, net	$	2,242	$	5,011

Schedule of aggregate minimum future principal payments due in connection with the FFG Loans

As of June 30, 2022, the aggregate minimum future principal payments due in connection with the FFG Loans are summarized as follows (in thousands):


Payments Due by Calendar Year	Amount
2022 (remaining 6 months)		—
2023		1,684
2024		1,109
2025		—
2026		—
Thereafter		—
Total	$	2,793

Stock-based compensation (Tables)

6 Months Ended

Jun. 30, 2022

Stock-based compensation

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


	Three months ended June 30,				Six months ended June 30,
	2022		2021		2022		2021

Risk-free interest rate	2.96	%	1.07	%	2.87	%	1.07	%
Expected term (in years)	6.1		6.1		6.0		6.1
Expected volatility	84.8	%	85.5	%	84.9	%	85.5	%
Expected dividends	—	%	—	%	—	%	—	%

Schedule of summary of stock option activity

The following table summarizes the Company’s stock option activity since January 1, 2022 (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, 2021	4,231,178	$	9.21	7.5	$	1,640
Granted	2,028,291		1.65
Exercised	(22,096)		0.10
Forfeited	(123,205)		8.78
Outstanding as of June 30, 2022	6,114,168	$	6.74	8.0	$	1,097

Options exercisable as of June 30, 2022	2,913,971	$	8.22	6.7	$	1,093
Options unvested as of June 30, 2022	3,200,197	$	5.38	9.1	$	4

Schedule of stock-based compensation expense

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


	Three months ended June 30,				Six months ended June 30,
	2022		2021		2022		2021
Research and development expenses	$	522	$	1,145	$	1,140	$	1,769
General and administrative expenses		859		1,482		1,862		2,379
	$	1,381	$	2,627	$	3,002	$	4,148

Net loss per share (Tables)

6 Months Ended

Jun. 30, 2022

Net loss per share

Schedule of basic and diluted 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 per share amounts):


	Three months ended June 30,				Six months ended June 30,
	2022		2021		2022		2021
Numerator:
Net loss	$	(16,356)	$	(17,153)	$	(34,324)	$	(34,391)

Denominator:
Weighted-average common shares outstanding, basic and diluted		54,698,007		29,826,269		46,694,976		29,807,382
Weighted-average Series A convertible preferred shares outstanding, basic and diluted, presented as if converted into common stock⁽¹⁾		1,697,000		2,978,000		1,697,000		2,978,000
Weighted-average Series A-1 convertible preferred shares outstanding, basic and diluted, presented as if converted into common stock⁽¹⁾		15,800,000		—		10,300,552		—
Total number of shares used to calculate net loss per share, basic and diluted		72,195,007		32,804,269		58,692,528		32,785,382

Net loss per share, basic and diluted	$	(0.23)	$	(0.52)	$	(0.58)	$	(1.05)

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


	Three and six months ended June 30,
	2022	2021
Options issued and outstanding	6,114,168	4,283,995
Unvested restricted stock units	—	20,053
Total	6,114,168	4,304,048

Summary of significant accounting policies - Going concern (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended		12 Months Ended
	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Summary of significant accounting policies
Net losses	$ (16,356)	$ (17,968)	$ (17,153)	$ (17,238)	$ (34,324)	$ (34,391)	$ (75,700)
Accumulated deficit	$ (257,090)				$ (257,090)		$ (222,766)

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(22))
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8933-108599

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 4
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+ Details

- Definition

The cumulative amount of the reporting entity's undistributed earnings or deficit.

+ References + Details

Summary of significant accounting policies - Property and equipment (Details)	6 Months Ended
	Jun. 30, 2022
Laboratory equipment \| Minimum
Property and equipment
Estimated useful life (in years)	2 years
Laboratory equipment \| Maximum
Property and equipment
Estimated useful life (in years)	10 years
Furniture and fixtures \| Minimum
Property and equipment
Estimated useful life (in years)	2 years
Furniture and fixtures \| Maximum
Property and equipment
Estimated useful life (in years)	10 years
Computer equipment and software \| Minimum
Property and equipment
Estimated useful life (in years)	2 years
Computer equipment and software \| Maximum
Property and equipment
Estimated useful life (in years)	4 years

Summary of significant accounting policies - Others (Details)	6 Months Ended
	Jun. 30, 2022 Program item
Summary of significant accounting policies
Number of preclinical research programs \| Program	2
Number of combined performance obligation for each research program	1
Number of research program performance obligations	2

Collaboration and Licensing Agreements (Details) $ in Millions	1 Months Ended	3 Months Ended		6 Months Ended
	Jun. 30, 2018 USD ($) item	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)	Dec. 31, 2021 USD ($)
Collaboration and Licensing Agreements
Contract asset relating to the sublicense payment		$ 0.3		$ 0.3
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	$ 8.0
Upfront and milestone payments included in deferred revenues		$ 16.2		$ 16.2		$ 4.3
Percentage of upfront payment included in deferred revenue expected to be recognized in 2022		42.00%		42.00%
Percentage of upfront payment included in deferred revenue expected to be recognized in 2023		31.00%		31.00%
Percentage of upfront payment included in deferred revenue expected to be recognized in 2024		18.00%		18.00%
Percentage of upfront payment included in deferred revenue expected to be recognized in 2025		9.00%		9.00%
Cost reimbursements for research and development services included in deferred revenues		$ 0.6		$ 0.6		1.2
Revenue recognized from milestone payments		1.0	$ 1.0	1.6	$ 1.7
Revenue recognized from cost reimbursements for research and development services		1.7	4.4	2.5	9.0
Revenue recognized from cost reimbursements for research and development services initially recorded as deferred revenue		$ 0.5	$ 0.4	$ 0.6	$ 0.7
Contract asset relating to the sublicense payment						$ 0.3
Development Milestones \| HBV program
Collaboration and Licensing Agreements
Total milestone amount	140.0
Development Milestones \| HIV program
Collaboration and Licensing Agreements
Option exercise payment	10.0
Development Milestones \| HIV program \| Maximum
Collaboration and Licensing Agreements
Total milestone amount	172.5
Commercial Milestones \| HBV program
Collaboration and Licensing Agreements
Total milestone amount	50.0
Commercial Milestones \| HIV program
Collaboration and Licensing Agreements
Total milestone amount	$ 65.0

Fair Value of Financial Assets (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2022	Dec. 31, 2021
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
Total	80,094	$ 35,403
Recurring \| Money market funds
Fair Value of Financial Assets
Cash equivalents	80,094	35,403
Recurring \| Level 1
Fair Value of Financial Assets
Total	80,094	35,403
Recurring \| Level 1 \| Money market funds
Fair Value of Financial Assets
Cash equivalents	$ 80,094	$ 35,403

Property, plant and equipment, net (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Property and equipment
Property and equipment, gross	$ 23,656	$ 22,718
Less: Accumulated depreciation	(6,704)	(6,366)
Property and equipment, net	16,952	16,352
Land
Property and equipment
Property and equipment, gross	1,917	2,072
Leasehold improvements
Property and equipment
Property and equipment, gross	3,096	3,348
Construction in progress
Property and equipment
Property and equipment, gross	9,413	7,746
Laboratory equipment
Property and equipment
Property and equipment, gross	6,850	7,025
Furniture and fixtures
Property and equipment
Property and equipment, gross	608	651
Computer equipment and software
Property and equipment
Property and equipment, gross	$ 1,772	$ 1,876

Receivable research incentive (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Receivable research incentive
Receivable research incentive	$ 16,453		$ 16,453		$ 14,271
Income related to the incentive program recorded as grant income	$ 1,700	$ 2,300	$ 3,400	$ 4,300

Accrued expenses and other current liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Accrued expenses and other current liabilities
Salaries and bonuses	$ 3,667	$ 4,754
Social security contributions	370	250
Unearned grant income (current)	411	693
Sublicense fees		304
Accrued external research and development expenses	2,954	2,165
Accrued external general and administration expenses	910	629
Accrued for property and equipment acquisitions		7
Finance lease liabilities		21
Other accruals and liabilities	377	57
Total	$ 8,689	$ 8,880

Loans payable (Details) - USD ($) $ in Thousands	6 Months Ended
Loans payable (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Loans payable
Loans from FFG	$ 2,793		$ 6,074
Unamortized debt discount	(551)		(1,063)
Total loans payable, net	$ 2,242		$ 5,011
Interest rate (as a percent)	0.75%
Principal payment	$ 2,952	$ 0

Loans payable - Schedule of aggregate minimum future principal payments (Details) $ in Thousands	Jun. 30, 2022 USD ($)
Long-term Debt, Fiscal Year Maturity [Abstract]
2023	$ 1,684
2024	1,109
Total	$ 2,793

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References + Details

Common stock, Class A common stock and convertible preferred stock (Details) $ / shares in Units, $ in Thousands			6 Months Ended
	Mar. 04, 2022 USD ($) $ / shares shares	Feb. 15, 2022 USD ($) $ / shares shares	Jun. 30, 2022 USD ($) Vote $ / shares shares	Jun. 30, 2021 USD ($)	Mar. 31, 2022 $ / shares	Dec. 31, 2021 shares
Preferred Stock, Shares Authorized			10,000,000			10,000,000
Net proceeds from public offering \| $	$ 70,200
Proceeds from issuance of common stock, net of issuance costs \| $			$ 45,689	$ 237
Register for Resale of Common Stock, Additional Issuances		4 months
Common stock
Common Stock, Shares Authorized			200,000,000			100,000,000
Common stock, issued (in shares)			50,884,796			27,383,483
Common stock, outstanding (in shares)			50,884,796			27,383,483
Issuance of common stock	21,700,000
Share Price \| $ / shares	$ 2.00
Number of votes \| Vote			1
Class A common stock
Common Stock, Shares Authorized			3,900,000			3,900,000
Common stock, issued (in shares)			3,819,732			3,819,732
Common stock, outstanding (in shares)			3,819,732			3,819,732
Number of common stock issued upon conversion of each share			1
Series A Convertible Preferred Stock
Preferred stock shares Designated			2,978			2,978
Preferred Stock, Shares Issued			1,697
Preferred Stock, Shares Outstanding			1,697			1,697
Series A -1 Convertible Preferred Stock
Preferred stock shares Designated			15,800			0
Preferred Stock, Shares Issued			15,800
Preferred Stock, Shares Outstanding			15,800			0
Issuance of common stock	15,800
Share Price \| $ / shares	$ 2,000.00
Series A and Series A-1 convertible preferred stock
Number of common stock issued upon conversion of each share			1,000
Threshold Percentage For Conversion			9.99%
Liquidation preference per share \| $ / shares			$ 0.001
Stock Purchase Agreement
Net proceeds from public offering \| $		$ 35,000
Issuance of common stock		1,666,666
Proceeds from issuance of common stock, net of issuance costs \| $		$ 5,000
Share Price \| $ / shares		$ 3.00
Outstanding amount \| $		$ 30,000
Percentage of premium		30.00%
Stock Purchase Agreement \| Gilead \| Gilead Collaboration and License Agreement
Ownership percentage		19.90%
Stock Purchase Agreement \| Common stock
Share Price \| $ / shares					$ 3.00

Stock-based compensation - 2018 Stock Option and Grant Plan (Details)	6 Months Ended
	Jun. 30, 2022 installment shares	Dec. 31, 2021 shares
Stock-based compensation
Options outstanding	6,114,168	4,231,178
2018 Stock Option and Grant Plan
Stock-based compensation
Vesting period	4 years
Options outstanding	927,115
2018 Stock Option and Grant Plan \| Vesting upon first anniversary
Stock-based compensation
Percentage of options vesting	25.00%
2018 Stock Option and Grant Plan \| Vesting in equal quarterly installments
Stock-based compensation
Percentage of options vesting	75.00%
Number of quarterly installments for vesting \| installment	12

Stock-based compensation - 2019 Stock Option and Incentive Plan (Details)	Apr. 01, 2019 installment shares
Stock-based compensation
Number of common stock entitled for each option upon the exercise of the option \| shares	1
2019 Stock Option and Incentive Plan
Stock-based compensation
Number stock option authorized \| shares	5,878,814
Number of shares outstanding were cumulatively increased	4.00%
Vesting period	4 years
2019 Stock Option and Incentive Plan \| Non Executive Directors
Stock-based compensation
Vesting period	3 years
2019 Stock Option and Incentive Plan \| Vesting upon first anniversary
Stock-based compensation
Percentage of options vesting	25.00%
2019 Stock Option and Incentive Plan \| Vesting upon first anniversary \| Non Executive Directors
Stock-based compensation
Percentage of options vesting	33.00%
2019 Stock Option and Incentive Plan \| Vesting in equal quarterly installments
Stock-based compensation
Percentage of options vesting	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	67.00%
Number of quarterly installments for vesting \| installment	8

Stock-based compensation - Stock option valuation (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Assumptions used in the Black-Scholes option-pricing model
Risk-free interest rate	2.96%	1.07%	2.87%	1.07%
Expected term (in years)	6 years 1 month 6 days	6 years 1 month 6 days	6 years	6 years 1 month 6 days
Expected volatility	84.80%	85.50%	84.90%	85.50%

Stock-based compensation - Stock option activity (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended		12 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Number of Shares
Beginning balance	4,231,178
Granted	2,028,291
Exercised	(22,096)
Forfeited	(123,205)
Ending balance	6,114,168		4,231,178
Option exercisable	2,913,971
Option unvested	3,200,197
Weighted Averaged Exercise Price
Beginning balance	$ 9.21
Granted	1.65
Exercised	0.10
Forfeited	8.78
Ending balance	6.74		$ 9.21
Option exercisable	8.22
Option unvested	$ 5.38
Weighted Average Remaining Contractual Term
Weighted Average Remaining Contractual Term (in years)	8 years		7 years 6 months
Weighted Average Remaining Contractual Term, option exercisable	6 years 8 months 12 days
Weighted Average Remaining Contractual Term, option unvested	9 years 1 month 6 days
Aggregate Intrinsic Value, beginning balance	$ 1,640
Aggregate Intrinsic Value, ending balance	1,097		$ 1,640
Aggregate Intrinsic Value, option exercisable	1,093
Aggregate Intrinsic Value, option unvested	$ 4
Fair value per common stock used for calculating intrinsic values	$ 1.63		$ 2.33
Cash received from option exercise under share-based payment arrangements	$ 2	$ 237

Stock-based compensation - Common Stock Awards (Details) - Common Stock Awards - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Jun. 30, 2022	Mar. 31, 2022
Stock-based compensation
Share Price		$ 3.00
Share-based awards granted	0	112,551
Aggregate fair value of share-based awards granted		$ 0.2
Grant date fair value per share		$ 1.50

Stock-based compensation - Stock-based compensation (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Stock-based compensation
Stock-based compensation expense	$ 1,381	$ 2,627	$ 3,002	$ 4,148
Research and development expenses
Stock-based compensation
Stock-based compensation expense	522	1,145	1,140	1,769
General and Administrative Expense
Stock-based compensation
Stock-based compensation expense	$ 859	$ 1,482	$ 1,862	$ 2,379

Income taxes (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
Income taxes (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Income taxes
Income tax benefits for the net operating losses incurred	$ 0	$ 0	$ 0	$ 0

Commitments and contingencies - Operating and Finance Leases (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Commitments and contingencies
Cash balance maintained to secure a letter of credit associated with a real estate lease	$ 418	$ 425
Operating lease right-of-use assets	4,670	5,673
Finance lease right-of-use assets	0	90
Outstanding operating lease obligations	4,600	5,600
Current operating lease liability	1,647	1,682
Non-current operating lease liability	2,988	3,911
Outstanding finance lease obligations	$ 0	$ 100
Weighted average discount rate on operating lease liabilities (as a percent)	1.40%
Weighted average lease term remaining on operating lease liabilities (in years)	3 years 3 months 18 days

Commitments and contingencies - Others (Details) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2022 USD ($)	Jun. 30, 2022 USD ($)
Lessee, Lease, Description [Line Items]
Non-cancellable obligations	$ 8.5	$ 8.5
2022 deliverables (remaining six months)	4.5	4.5
2023 deliverables	4.0	4.0
Licensing fees from intellectual property licenses	0.4	0.7
Maximum
Lessee, Lease, Description [Line Items]
2024 deliverables	$ 0.1	$ 0.1

Net loss per share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended				6 Months Ended		12 Months Ended
	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Numerator:
Net loss	$ (16,356)	$ (17,968)	$ (17,153)	$ (17,238)	$ (34,324)	$ (34,391)	$ (75,700)
Denominator:
Weighted-average common shares outstanding, basic and diluted	54,698,007		29,826,269		46,694,976	29,807,382
Weighted-average Series A convertible preferred shares outstanding, basic and diluted, presented as if converted into common stock	1,697,000		2,978,000		1,697,000	2,978,000
Weighted-average Series A-1 convertible preferred shares outstanding, basic and diluted, presented as if converted into common stock	15,800,000				10,300,552
Total number of shares used to calculate net loss per share, basic	72,195,007		32,804,269		58,692,528	32,785,382
Total number of shares used to calculate net loss per share, diluted	72,195,007		32,804,269		58,692,528	32,785,382
Net loss per share - basic	$ (0.23)		$ (0.52)		$ (0.58)	$ (1.05)
Net loss per share - diluted	$ (0.23)		$ (0.52)		$ (0.58)	$ (1.05)
Number of common stock issued upon conversion of each share of Preferred Stock	1,000				1,000
Number of common stock issuable upon conversion of Series A convertible preferred stock	1,697,000				1,697,000
Number of common stock issuable upon conversion of Series A-1 convertible preferred stock	15,800,000				15,800,000

Net loss per share - Antidilutive securities (Details) - shares	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Anti-dilutive securities
Anti-dilutive shares	6,114,168	4,304,048
Options
Anti-dilutive securities
Anti-dilutive shares	6,114,168	4,283,995
Restricted stock units
Anti-dilutive securities
Anti-dilutive shares		20,053