0001558370-21-003176 | 10-K | XBRL Viewer

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
Document and Entity Information - USD ($) $ in Millions	Dec. 31, 2020	Mar. 07, 2021	Jun. 30, 2020
Document Information [Line Items]
Document Type	10-K
Document Period End Date	Dec. 31, 2020
Entity Registrant Name	HOOKIPA Pharma Inc.
Title of 12(b) Security	Common Stock, $0.0001 Par Value per Share
Trading Symbol	HOOK
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	true
Entity Shell Company	false
Entity Public Float			$ 207.2
Entity Central Index Key	0001760542
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Amendment Flag	false
Common stock
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		25,969,612
Class A common stock
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		3,819,732

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 142,743	$ 113,151
Accounts receivable	5,542	1,537
Receivable research incentives	15,115	8,190
Prepaid expenses and other current assets	8,104	5,139
Total current assets	171,504	128,017
Non-current assets:
Restricted cash	434	424
Property and equipment, net	6,219	5,126
Operating lease right of use assets	6,452	7,875
Finance lease right of use assets	1,298	1,602
Other non-current assets	1,910	701
Total non-current assets	16,313	15,728
Total assets	187,817	143,745
Current liabilities
Accounts payable	8,009	944
Deferred revenues	3,750	3,591
Operating lease liabilities, current	1,998	1,814
Accrued expenses and other current liabilities	7,386	8,406
Total current liabilities	21,143	14,755
Non-current liabilities
Loans payable, non-current	4,537	3,495
Operating lease liabilities, non-current	3,819	5,290
Deferred revenues, non-current	784	72
Other non-current liabilities	1,411	2,234
Total non-current liabilities	10,551	11,091
Total liabilities	31,694	25,846
Commitments and contingencies (Note 13)
Stockholders' equity:
Preferred stock, $0.0001 par value; 10,000,000 shares authorized at December 31, 2020 and December 31, 2019, respectively; Series A convertible preferred stock, 2,978 shares and zero shares designated, 2,978 shares and zero shares issued and outstanding at December 31, 2020 and December 31, 2019, respectively	0
Additional paid-in capital	309,288	225,568
Accumulated other comprehensive loss	(6,067)	(4,653)
Accumulated deficit	(147,101)	(103,019)
Total stockholders' equity	156,123	117,899
Total liabilities and stockholders’ equity	187,817	143,745
Common stock
Stockholders' equity:
Common stock	3	3
Class A common stock
Stockholders' equity:
Common stock	$ 0	$ 0

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2020	Dec. 31, 2019
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 authorized	2,978	0
Preferred stock, shares issued	2,978	0
Preferred stock, shares outstanding	2,978	0
Common stock, shares issued	2,978
Common stock, shares outstanding	2,978
Common stock
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	25,948,712	21,746,392
Common stock, shares outstanding	25,948,712	21,746,392
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

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS
Revenue from collaboration and licensing	$ 19,584	$ 11,942	$ 7,629
Operating expenses:
Research and development	(54,787)	(46,312)	(21,965)
General and administrative	(18,082)	(16,715)	(6,844)
Total operating expenses	(72,869)	(63,027)	(28,809)
Loss from operations	(53,285)	(51,085)	(21,180)
Other income (expense):
Grant income	6,517	6,737	5,612
Interest income	400	1,587	0
Interest expense	(786)	(877)	(778)
Other income and expenses, net	3,072	601	133
Total other income, net	9,203	8,048	4,967
Net loss before tax	(44,082)	(43,037)	(16,213)
Income tax expense	0	0	(24)
Net loss	(44,082)	(43,037)	(16,237)
Other comprehensive loss:
Foreign currency translation gain (loss), net of tax	(1,414)	(933)	(2,358)
Comprehensive loss	$ (45,496)	$ (43,970)	$ (18,595)
Net loss per share - basic and diluted	$ (1.69)	$ (2.41)	$ (17.76)

CONSOLIDATED STATEMENTS OF REDEEMABLE CONVERTIBLE PREFERRED STOCK, CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS’ EQUITY (DEFICIT) - USD ($) $ in Thousands	Redeemable Convertible Preferred Stock Series D convertible preferred stock	Redeemable Convertible Preferred Stock	Convertible Preferred Stock Series A Convertible Preferred Stock	Convertible Preferred Stock	Common Stock Common stock	Common Stock Class A common stock	Additional Paid-In Capital Series A Convertible Preferred Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit	Series A Convertible Preferred Stock	Total
Balance at the beginning of the period at Dec. 31, 2017		$ 104,774
Balance at the beginning of the period (in shares) at Dec. 31, 2017		1,323,506
Balance at the end of the period at Dec. 31, 2018		$ 104,774
Balance at the end of the period (in shares) at Dec. 31, 2018		1,323,506
Balance at the beginning of the period at Dec. 31, 2017					$ 0			$ 2,451	$ (1,362)	$ (43,745)		$ (42,656)
Balance at the beginning of the period (in shares) at Dec. 31, 2017					911,777
Increase (Decrease) in Stockholders' Equity
Issuance of common stock upon exercise of stock options					$ 0			9				9
Issuance of common stock upon exercise of stock options (in shares)					94,818
Foreign currency translation adjustment, net of tax									(2,358)			(2,358)
Stock-based compensation expense								867				867
Net loss										(16,237)		(16,237)
Balance at the end of the period at Dec. 31, 2018					$ 0			3,327	(3,720)	(59,982)		$ (60,375)
Balance at the end of the period (in shares) at Dec. 31, 2018					1,006,595
Balance at the end of the period (in shares) at Mar. 31, 2019												1,580,506
Increase (Decrease) in Stockholders' Equity
Net loss												$ (9,329)
Balance at the beginning of the period at Dec. 31, 2018		$ 104,774
Balance at the beginning of the period (in shares) at Dec. 31, 2018		1,323,506
Increase (Decrease) in Temporary Equity
Issuance of preferred stock, net of issuance costs	$ 37,274
Issuance of preferred stock, net of issuance costs (in shares)	257,000
Conversion of Series A, B, C and D preferred stock into common stock upon initial public offering		$ (142,048)
Conversion of Series A, B, C and D preferred stock into common stock upon initial public offering (in shares)		(1,580,506)
Balance at the beginning of the period at Dec. 31, 2018					$ 0			3,327	(3,720)	(59,982)		(60,375)
Balance at the beginning of the period (in shares) at Dec. 31, 2018					1,006,595
Increase (Decrease) in Stockholders' Equity
Issuance of stock					$ 1			74,614				74,615
Issuance of stock (in shares)					6,000,000
Issuance of common stock upon exercise of stock options					$ 0			16				16
Issuance of common stock upon exercise of stock options (in shares)					157,636
Foreign currency translation adjustment, net of tax									(933)			(933)
Conversion of Series A, B, C and D preferred stock into common stock upon initial public offering					$ 2	$ 0		142,046				142,048
Conversion of Series A, B, C and D preferred stock into common stock upon initial public offering (in shares)					14,582,161	3,819,732
Stock-based compensation expense								5,565				5,565
Net loss										(43,037)		(43,037)
Balance at the end of the period at Dec. 31, 2019					$ 3	$ 0		225,568	(4,653)	(103,019)		117,899
Balance at the end of the period (in shares) at Dec. 31, 2019					21,746,392	3,819,732
Increase (Decrease) in Stockholders' Equity
Issuance of stock			$ 0		$ 0		$ 32,426	42,574			$ 32,426	42,574
Issuance of stock (in shares)			2,978		3,910,000
Issuance of common stock upon exercise of stock options					$ 0			63				$ 63
Issuance of common stock upon exercise of stock options (in shares)					255,011							255,011
Foreign currency translation adjustment, net of tax									(1,414)			$ (1,414)
Vesting of restricted stock					$ 0			0
Vesting of restricted stock (in shares)					1,060
Vesting of equity grants					$ 0			0
Vesting of equity grants (in shares)					36,249
Stock-based compensation expense								8,657				8,657
Net loss										(44,082)		(44,082)
Balance at the end of the period at Dec. 31, 2020				$ 0	$ 3	$ 0		$ 309,288	$ (6,067)	$ (147,101)		$ 156,123
Balance at the end of the period (in shares) at Dec. 31, 2020				2,978	25,948,712	3,819,732

CONSOLIDATED STATEMENTS OF REDEEMABLE CONVERTIBLE PREFERRED STOCK, CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS’ EQUITY (DEFICIT) (Parenthetical) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) $ / shares
Share price (in USD per share) \| $ / shares	$ 12.23
Series D convertible preferred stock
Issuance costs \| $	$ 158
Common stock \| IPO
Share price (in USD per share) \| $ / shares	$ 14.00
Issuance costs \| $	$ 9,386

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Operating activities:
Net loss	$ (44,082)	$ (43,037)	$ (16,237)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	8,657	5,565	867
Depreciation and amortization expense	4,150	3,067	640
Other non-cash items	53	52	7
Changes in operating assets and liabilities:
Accounts receivable	(3,576)	(3,619)	(4,991)
Prepaid expenses and other current assets	(8,111)	(6,005)	(7,049)
Other non-current assets	(1,080)	869	(1,465)
Accounts payable	6,298	4,203	3,413
Deferred revenues	511	(4,442)	8,587
Operating lease liabilities	(1,833)	(2,396)
Accrued expenses and other liabilities	(326)	4,012	1,230
Net cash used in operating activities	(39,339)	(41,731)	(14,998)
Investing activities:
Purchases of property and equipment	(2,371)	(1,999)	(2,150)
Net cash used in investing activities	(2,371)	(1,999)	(2,150)
Financing activities:
Payments related to finance leases	(108)	(1,437)
Proceeds from issuance of redeemable convertible preferred stock, net of issuance costs		37,274	6,439
Proceeds from issuance of convertible preferred stock, net of issuance costs	32,426
Proceeds from issuance of common stock, net of issuance costs	42,637	74,756	9
Payments for deferred offering costs	(224)
Proceeds from borrowings			425
Repayments of borrowings	(1,311)	(842)
Net cash provided by financing activities	73,420	109,751	6,873
Net increase (decrease) in cash, cash equivalents and restricted cash	31,710	66,021	(10,275)
Cash, cash equivalents and restricted cash at beginning of period	113,575	48,580	61,362
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(2,108)	(1,026)	(2,507)
Cash, cash equivalents and restricted cash at end of period	143,177	113,575	48,580
Supplemental disclosure of cash flow information:
Cash paid for interest	(97)	(64)	(71)
Cash paid for income taxes	0		(24)
Supplemental disclosure of non-cash financing activities:
Conversion of redeemable preferred shares upon the IPO		142,048
Property and equipment additions in accounts payable and accrued expenses	$ 16	$ (10)	$ 545

Nature of the business and organization	12 Months Ended
Nature of the business and organization	Dec. 31, 2020
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

12 Months Ended

Dec. 31, 2020

Summary of significant accounting policies

Summary of significant accounting policies

2. Summary of significant accounting policies

Basis of presentation

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

Stock split

On April 5, 2019, the Company effected a 11.643‑for-one stock split of its issued and outstanding shares of common stock. The par value of the common stock was not adjusted as a result of the split. All issued and outstanding share and per share amounts of common stock and options included in the accompanying consolidated financial statements have been adjusted to reflect this stock split for all periods presented. The conversion ratios for each series of the Company’s redeemable convertible preferred stock (see Note 9) have been adjusted proportionally.

Transaction between entities under common control

In June 2018, the Company acquired all of the shares of its parent company, Hookipa Biotech AG, against issuance of 78,311 shares of common stock and 1,323,506 shares of redeemable convertible preferred stock to the shareholders of Hookipa Biotech AG, who became the sole shareholders of the Company. The transaction was recorded as a transaction between entities under common control that led to a change in the reporting entity. In the accompanying consolidated financial statements, the assets and liabilities and relating operations of the transferring entity are retrospectively presented at their carrying amounts without a change in the basis for all periods during which the transferring entity was under common control. The share capital as well as the share and per share information included in the accompanying consolidated financial statements have been retrospectively adjusted to reflect the share capital of the Company after the transaction. Differences in the par value of common stock between the transferring and the receiving entity were reflected by adjustments to redeemable convertible preferred stock and additional paid-in capital.

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 December 31, 2020, 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 $44.1 million, $43.0 million and $16.2 million for the years ended December 31, 2020, 2019 and 2018, respectively. As of December 31, 2020, the Company had an accumulated deficit of $147.1 million. The Company expects to continue to generate operating losses in the foreseeable future. As of March 18, 2021, the filing date of this Annual Report on Form 10‑K, the Company expected that its cash and cash equivalents would 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 consolidated financial statements.

The Company will seek additional funding in order to reach its development and commercialization objectives. The Company will 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 consolidated financial statements have been prepared assuming that the Company will continue as a going concern, which contemplates the realization of assets and the settlement of liabilities and commitments in the normal course of business. The consolidated financial statements do not reflect any adjustments relating to the recoverability and classification of assets or the amounts and classification of liabilities that might 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 consolidated financial statements include, but are not limited to, the recognition of revenue and income, the accrual of research and development expenses, the present value of lease right of use assets and corresponding liabilities, the valuation of common and preferred stock, the valuation of stock-based awards and the valuation of liabilities. 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.

The full extent to which the COVID-19 pandemic will directly or indirectly impact the Company’s business, results of operations and financial condition, will depend on future developments that are highly uncertain, including as a result of new information that may emerge concerning COVID-19 and the actions taken to contain it or treat COVID-19, as well as the economic impact on local, regional, national and international customers and markets. 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 consolidated financial statements, the Company is not aware of any specific event or circumstance that would require the Company to update estimates, judgments or revise the carrying value of any assets or liabilities. Actual results may differ from those estimates or assumptions.

Foreign currency and currency translation

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

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

Concentrations of credit risk and of significant suppliers

Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash, cash equivalents and short-term bank deposits held with banks in excess of publicly insured limits. The net proceeds from the Company’s offerings have been deposited in interest-bearing bank accounts with investment grade U.S. financial institutions and have been partially invested in a money market fund as of December 31, 2020. The money market fund, held in U.S. dollar, is primarily invested in U.S. and foreign short-term debt obligations. As of December 31, 2019 and December 31, 2020, 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 December 31, 2020 and December 31, 2019, respectively, one customer accounted for the majority of the accounts receivable balance. For the years ended December 31, 2020, December 31, 2019 and December 31, 2018 one customer accounted for the majority of the Company’s sales. No other customers accounted for more 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 December 31, 2019 and December 31, 2020 cash equivalents consisted of money market funds.

Deferred offering costs

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

Fair value measurements

Certain assets and liabilities are carried at fair value under GAAP. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable:

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

Level 2 - Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data.

Level 3 - Unobservable inputs that are supported by little or no market activity and that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques.

The Company’s cash equivalents are carried at fair value, determined according to the fair value hierarchy described above (see Note 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		5 years
Laboratory equipment		3 - 10 years
Furniture and fixtures		3 - 10 years
Computer equipment and software		3 - 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.

Leases

The Company adopted the new leasing standards as of January 1, 2019. The new leasing standards were adopted using the modified retrospective transition approach, as of January 1, 2019, with no restatement of prior periods or cumulative adjustment to retained earnings. Upon adoption, the Company elected the package of transition practical expedients, which allowed the Company to carry forward prior conclusions related to whether any expired or existing contracts are or contain leases, the lease classification for any expired or existing leases and initial direct costs for existing leases. The Company also elected the practical expedient to not reassess certain land easements, elected to use hindsight in determining the lease term and made an accounting policy election to not recognize leases with an initial term of 12 months or less within the consolidated balance sheets and to recognize those lease payments on a straight-line basis in the consolidated statements of operations over the lease term. Upon adoption of the new leasing standards an operating lease asset of $3.3 million and a corresponding operating lease liability of $3.3 million were recorded in the consolidated balance sheets. The adoption of the new leasing standards did not have a material impact on the Company’s consolidated statements of operations.

The determination whether an arrangement qualifies as a lease is made at contract inception. Operating lease assets represent the Company’s right to use an underlying asset for the lease term and operating lease liabilities represent its obligation to make lease payments arising from the lease. Operating lease assets and 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 operating lease assets may include lease incentives, stated rent increases and escalation clauses linked to rates of inflation when determinable and are recognized as operating lease assets on the consolidated balance sheets. 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 accrued expenses and other current liabilities and in non-current operating lease liabilities in the consolidated balance sheets. Lease expense for minimum lease payments is recognized on a straight-line basis over the lease term. The right-of-use 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. No amortization expense associated with the Company's cloud computing arrangements has been recognized during the fiscal year ended December 31, 2020 (see Note 5). The Company tests for impairment whenever events or changes in circumstances indicate that the carrying amount may not be recoverable.

Impairment of long-lived assets

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

If an impairment review is performed to evaluate a long-lived asset group for recoverability, the Company compares forecasts of undiscounted cash flows expected to result from the use and eventual disposition of the long-lived asset group to its carrying value. An impairment loss would be recognized in loss from operations when estimated undiscounted future cash flows expected to result from the use of an asset group are less than its carrying amount. The impairment loss would be based on the excess of the carrying value of the impaired asset group over its fair value, determined based on discounted cash flows. The Company did not record any impairment losses on long-lived assets during the years ended December 31, 2020, 2019 and 2018.

Segment information

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

Revenue recognition from contracts with customers

The Company entered into a collaboration and license agreement (the “Gilead Agreement”) with Gilead Sciences, Inc. (“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”). The Company's performance obligations under the terms of this 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 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

The non-refundable upfront-payment received by the Company under the Gilead Agreement is 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.

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 in the period in which the goods or services are received and external costs are recognized. 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.

Research and development costs

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

All patent-related costs incurred in connection with filing and prosecuting patent applications are classified as research and development expenses and expensed as incurred due to the uncertainty about the recovery of the expenditure. Upfront payments, milestone payments and annual payments made for the licensing of technology are generally expensed as research and development in the period in which they are incurred. Incremental sublicense fees triggered by contracts with customers are capitalized and expensed as research and development expenses over the period in which the related revenue is recognized.

Research and manufacturing contract costs and accruals

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

Government grant agreements and research incentives

The Company recognizes funding from grants and research incentives received from Austrian government agencies as other income. Income from grants and incentives is recognized in the period during which the related qualifying expenses are incurred, provided that the conditions under which the grants or incentives were provided have been met. For grants under funding agreements and for proceeds under research incentive programs, the Company recognizes grant and incentive income in an amount equal to the estimated qualifying expenses incurred in each period multiplied by the applicable reimbursement percentage.

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

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

Redeemable convertible preferred stock

Upon the closing of the Company’s IPO on April 23, 2019, the Company’s outstanding redeemable convertible preferred stock automatically converted into shares of common stock or Class A common stock. Prior to the conversion, the Company had applied the guidance in ASC 480‑10‑S99‑3A, SEC Staff Announcement: Classification and Measurement of Redeemable Securities and had therefore classified the Series A, Series B, Series C and Series D redeemable convertible preferred stock as mezzanine equity. The redeemable convertible preferred stock was recorded outside of stockholders’ equity because, in the event of certain deemed liquidation events considered not solely within the Company’s control, such as a merger, acquisition and sale of all or substantially all of the Company’s assets, the convertible preferred stock would have become redeemable at the option of the holders. In the event of a change of control of the Company, proceeds received from the sale of such shares would have been distributed in accordance with the liquidation preferences set forth in the Company’s Preferred Stock agreements. The Company had determined not to adjust the carrying values of the redeemable convertible preferred stock to the liquidation preferences of such shares because of the uncertainty of whether or when such an event would occur.

Stock-based compensation

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

The Company classifies stock-based compensation expense in its Consolidated Statements of Operations and Comprehensive Loss in the same manner in which the recipient's payroll costs are classified or in which the recipient's service payments are classified.

Comprehensive loss

Comprehensive loss includes net loss and foreign currency translation adjustments. For the years ended December 31, 2020, 2019 and 2018, comprehensive loss included $1.4 million, $0.9 million and $2.4 million of foreign currency translation loss adjustments, respectively.

Net loss per share

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

The Company reported a net loss attributable to common stockholders for the years ended December 31, 2020, 2019 and 2018.

Income taxes

The Company accounts for income taxes under the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the consolidated financial statements or in the Company's tax returns. Under this method, deferred tax assets and liabilities are determined on the basis of the differences between the financial statement and tax bases of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period that includes the enactment date. Changes in deferred tax assets and liabilities are recorded in income tax expense. The Company assesses the likelihood that its deferred tax assets will be recovered from future taxable income and, to the extent it believes, based upon the weight of available evidence, that it is more likely than not that all or a portion of the deferred tax assets will not be realized, a valuation allowance is established through a charge to income tax expense. Potential for recovery of deferred tax assets is evaluated by estimating the future taxable profits expected and considering prudent and feasible tax planning strategies.

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

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 February 2016, the FASB issued ASU No. 2016‑02, Leases (Topic 842) (“ASU 2016‑02”), which sets out the principles for the recognition, measurement, presentation and disclosure of leases for both parties to a contract (i.e., lessees and lessors). The new standard requires lessees to apply a dual approach, classifying leases as either finance or operating leases based on the principle of whether or not the lease is effectively a financed purchase by the lessee. This classification will determine whether cost of the lease is recognized based on an effective interest method or on a straight-line basis over the term of the lease. A lessee is also required to record a right-of-use asset and a lease liability for all leases with a term of greater than 12 months regardless of their classification.

The FASB subsequently issued the following amendments to ASU 2016‑02 that have the same effective date and transition date: ASU No. 2018-01, Leases (Topic 842): Land Easement Practical Expedient for Transition to Topic 842, ASU No. 2018‑10, Codification Improvements to Topic 842, Leases, ASU No. 2018‑11, Leases (Topic 842): Targeted Improvements, ASU No. 2018‑20, Narrow-Scope Improvement for Lessors, and ASU No. 2019‑01, Leases (Topic 842): Codification Improvements. The Company adopted these amendments with ASU 2016‑02 (collectively, the new leasing standards) effective January 1, 2019. The new leasing standards were adopted using the modified retrospective transition approach, as of January 1, 2019, with no restatement of prior periods or cumulative adjustment to retained earnings. Upon adoption, the Company elected the package of transition practical expedients, which allowed the Company to carry forward prior conclusions related to whether any expired or existing contracts are or contain leases, the lease classification for any expired or existing leases and initial direct costs for existing leases. The Company also elected the practical expedient to not reassess certain land easements, elected to use hindsight in determining the lease term and made an accounting policy election to not recognize leases with an initial term of 12 months or less within the consolidated balance sheets and to recognize those lease payments on a straight-line basis in the consolidated statements of operations over the lease term. Upon adoption of the new leasing standards an operating lease asset of $3.3 million and a corresponding operating lease liability of $3.3 million were recorded in the consolidated balance sheets. The adoption of the new leasing standards did not have a material impact on the Company’s consolidated statements of operations.

The determination whether an arrangement was qualified as a lease was made at contract inception. Operating lease assets represent the Company’s right to use an underlying asset for the lease term and operating lease liabilities represent its obligation to make lease payments arising from the lease. Operating lease assets and 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 operating lease assets may include lease incentives, stated rent increases and escalation clauses linked to rates of inflation when determinable and are recognized as operating lease assets on the consolidated balance sheets. In addition, certain of the Company’s arrangements contain lease and non-lease components. The Company elected to generally separate lease payments from non-lease payments but applied an accounting choice to not separate lease payments from certain non-lease payments for its office and laboratory space leases and its car leases. Operating leases are reflected in operating lease assets, in accrued expenses and other current liabilities and in non-current operating lease liabilities in the consolidated balance sheets. Lease expense for minimum lease payments is recognized on a straight-line basis over the lease term.

In August 2018, the FASB issued ASU 2018‑15, Intangibles-Goodwill and Other-Internal-Use Software (Subtopic 350‑40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract. The amendments in this update align the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). The accounting for the service element of a hosting arrangement that is a service contract is not affected by the amendments in this update. The Company adopted the new standard on January 1, 2020 on a prospective basis. The adoption of this standard had no impact on the Company’s financial statements at the date of adoption; however, the Company anticipates the adoption of this standard will result in an increase in capitalized assets related to qualifying Cloud Computing Arrangements (“CCA”) implementation costs in future periods. Qualifying CCA implementation, set-up and other upfront costs incurred after January 1, 2020 are capitalized as other assets in the Company’s consolidated balance sheets. These assets will be expensed over the term of the hosting arrangement and such expense will be presented within the same line item in the Company’s consolidated statements of operations as the expense for fees for the associated hosting arrangement. These capitalized costs will be evaluated for impairment when events or changes in circumstances indicate that the carrying value of the capitalized implementation costs is not recoverable. For the year ended December 31, 2020, capitalized CCA implementation costs were not material.

In June 2016, the FASB issued ASU 2016-13, Financial Instruments-Credit Losses which was clarified and amended by the issuances of ASUs 2018-19, 2019-04, 2019-05 and 2019-11 in November 2018, April 2019, May 2019 and November 2019, respectively. The new standard requires that expected credit losses relating to financial assets measured on an amortized cost basis are measured using an expected-loss model, replacing the current incurred-loss model, and recorded through an allowance for credit losses. The guidance also establishes a new impairment model for available-for-sale debt securities. The Company adopted the new standard and the related amendments on January 1, 2020, on a modified retrospective basis, to the accounts receivable, contract asset balances and cash equivalents as of January 1, 2020. Under the current expected credit loss model, the Company adopted a provision matrix approach, utilizing historical loss rates based on the number of days past due, adjusted to reflect current economic conditions and forecasts of future economic conditions. The Company has never experienced a credit loss on its accounts receivable, contract assets or on the principal or interest receivable of its cash equivalents. Accordingly, the effect of the adoption on the financial statement line items of accounts receivable, contract assets and cash equivalents was not material as of January 1, 2020. As a result of the adoption, the cumulative-effect adjustment to reflect the incremental estimated lifetime expected credit losses on the accounts receivable balance as of January 1, 2020 is immaterial. Therefore, the Company recognized no cumulative-effect adjustment within retained earnings on its condensed consolidated balance sheet as of January 1, 2020. The Company has not presented the amortized cost basis within each credit quality indicator by year of origination as all of its accounts receivable are due within one year or less.

In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework – Changes to the Disclosure Requirements for Fair Value Measurement, (“ASU 2018-13”). The new standard removes certain disclosures, modifies certain disclosures and adds additional disclosures related to fair value measurement. The adoption of this guidance on January 1, 2020 did not have a material impact on the Company’s consolidated financial statements.

In August 2018, the FASB issued ASU 2018-14, Compensation – Retirement Benefits – Defined Benefit Plans – General (Subtopic 715-20): Disclosure Framework – Changes to the Disclosure Requirements for Defined Benefit Plans. Guidance, which modifies the disclosure requirements for defined benefit pension plans and other postretirement plans. The guidance removes disclosures that no longer are considered cost beneficial, clarifies the specific requirements of disclosures, and adds disclosure requirements identified as relevant. This guidance is effective for fiscal years ending after December 15, 2020. Early adoption was permitted. The Company early adopted this standard as of January 1, 2020 on a prospective basis. The adoption of this guidance on January 1, 2020 did not have a material impact on the Company’s consolidated financial statements.

In November 2018, the FASB issued ASU 2018-18, Clarifying the Interaction Between Topic 808 and 606, which clarifies when transactions between participants in a collaborative arrangement are within the scope of the FASB’s revenue standard, Topic 606. The adoption of this guidance on January 1, 2020 did not have a material impact on the Company’s consolidated financial statements.

In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes, which eliminates certain exceptions related to the general principles in ASC 740 and makes amendments to other areas with the intention of simplifying various aspects related to accounting for income taxes. The pronouncement is effective for fiscal years, and for interim periods within those fiscal years beginning after December 15, 2020, with early adoption permitted. The Company early adopted this standard as of January 1, 2020 on a prospective basis. The adoption of this guidance on January 1, 2020 did not have a material impact on the Company’s consolidated financial statements.

Recently Issued Accounting Pronouncements

In January 2021, the FASB issued ASU 2021-01, which amends the scope of the recent reference rate reform guidance (ASC 848). New optional expedients allow derivative instruments impacted by changes in the interest rate used for margining, discounting, or contract price alignment (i.e., discount transition) to qualify for certain optional relief. The new optional expedients for contract modifications and hedge accounting are expected to benefit companies, including those with certain centrally cleared derivatives affected by a discount rate transition in 2020. The guidance is effective immediately and can be applied retrospectively to any interim period beginning January 1, 2020 or prospectively to any new modifications in any period including or subsequent to the issuance date. The Company is currently assessing the impact that this guidance will have on its consolidated financial statements.

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 was effective upon issuance and will need to be applied for interim periods within those fiscal years beginning after December 15, 2023, with early adoption permitted. The Company is currently assessing the impact that this guidance will have on its consolidated financial statements.

In March 2020, the FASB issued ASU 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting, which provides optional expedients and exceptions to address the impact of reference rate reform where contracts, hedging relationships and other transactions that reference the London Interbank Offered Rate (“LIBOR”) or another reference rate need to be discontinued. This guidance was effective upon issuance and generally can be applied through December 31, 2022. The Company is currently assessing the impact that this guidance will have on its consolidated financial statements.

Collaboration and Licensing Agreements	12 Months Ended
Collaboration and Licensing Agreements	Dec. 31, 2020
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. Under the Gilead Agreement, the Company granted Gilead an exclusive, royalty-bearing license to the Company’s technology platforms. Upon entering into the agreement, the Company received a non-refundable $10.0 million upfront payment from Gilead. 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 a total of $280 million. The commercial milestones amount to a total of $100 million. 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 received in 2018 and a $4.0 million milestone payment received in 2020 were initially recorded as deferred revenue in the consolidated balance sheet and are recognized as revenue when revenue recognition criteria are met. As of December 31, 2020, $2.5 million of upfront and milestone payments were included as a liability in deferred revenues, current and non-current. Approximately 91% of deferred revenue related to the upfront and milestone payment is expected to be recognized as revenue in 2021 and the remaining 9% in 2022. As of December 31, 2020, $2.0 million of cost reimbursements for research and development services were included 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 year ended December 31, 2020, the Company recognized $2.0 million of the upfront payment received in 2018 and $2.4 million of the $4.0 million milestone payment received in 2020. Furthermore, the Company recognized $1.1 million from cost reimbursements which were initially recorded as deferred revenue in the consolidated balance sheet. In addition, the Company recognized $2.2 million milestone payments for milestones achieved in the year ended December 31, 2020 and $11.9 million revenue from cost reimbursements for research and development services. For the year ended December 31, 2019, revenue from reimbursement of research and development expenses was $4.3 million, and revenue from partial recognition of the upfront payment was $4.4 million. Additionally, the Company recognized $3.2 million in milestone payments for milestones achieved in the year ended December 31, 2019. For the year ended December 31, 2018, revenue from reimbursement of research and development expenses was $2.0 million, revenue from partial recognition of the upfront payment was $2.8 million, and revenue for the achievement of the first pre-clinical milestone was $2.8 million. Sublicense fees payable to certain licensors of technologies upon the receipt of the deferred upfront and milestone payments, were capitalized as a contract asset and will be amortized over the period in which the revenue from the triggering payment is recognized. As of December 31, 2020 and December 31, 2019, the contract asset and the liability relating to the sublicense payment was $0.1 million and $0.3 million, respectively.

Fair Value of Financial Assets

12 Months Ended

Dec. 31, 2020

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 December 31, 2020 Using
	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	35,397	$	—	$	—	$	35,397
Total	$	35,397	$	—	$	—	$	35,397


	Fair Value Measurement at December 31, 2019 Using
	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	35,132	$	—	$	—	$	35,132
Total	$	35,132	$	—	$	—	$	35,132

During the year ended December 31, 2020, 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 and equipment, net

12 Months Ended

Dec. 31, 2020

Property and equipment, net

Property and equipment, net

5. Property and equipment, net

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


	Year ended December 31,
	2020		2019

Leasehold improvements	$	3,322	$	1,919
Construction in progress		28		286
Laboratory equipment		5,982		4,555
Furniture and fixtures		430		524
Computer equipment and software		1,554		923
Property and equipment, gross		11,316		8,207
Less: Accumulated depreciation		(5,097)		(3,081)
Property and equipment, net	$	6,219	$	5,126

Depreciation expense for the years ended December 31, 2020, 2019 and 2018 was $1.7 million, $1.1 million and $0.6 million, respectively. Construction-in-progress as of December 31, 2020 related to implementation costs for a cloud computing arrangement which is a service contract. Construction-in-progress as of December 31, 2019 related to leasehold improvements in connection with the expansion of laboratories in the Company's leased facilities.

Leases

12 Months Ended

Dec. 31, 2020

Leases

Leases

6. Leases

The Company leases real estate, including office and laboratory space and has entered into various other agreements with respect to assets used in conducting its business. The Company’s leases have remaining lease terms ranging from less than 1 year to 3 years. Some of the lease agreements contain rent holidays and rent escalation clauses that were included in the calculation of the right of use assets and lease liabilities. The Company 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 consolidated balance sheet as of December 31, 2020.

Certain of the Company’s leases qualify as operating leases, and certain of its leases qualify as finance leases. The following table summarizes the presentation in the consolidated balance sheets (in thousands):


		December 31,		December 31,
	Balance sheet location	2020		2019
Assets
Operating lease assets, net	Operating lease right of use assets	$	6,452	$	7,875
Finance lease assets, net	Finance lease right of use assets		1,298		1,602
Total lease assets			7,750		9,477
Liabilities
Current operating lease liability	Operating lease liabilities, current		1,998		1,814
Current finance lease liability	Accrued expenses and other current liabilities		155		159
Total current lease liabilities			2,153		1,973
Non-current operating lease liability	Operating lease liabilities, non-current		3,819		5,290
Non-current finance lease liability	Other non-current liabilities		258		367
Total non-current lease liabilities			4,077		5,657
Total lease liabilities		$	6,230	$	7,630

In the year ended December 31, 2020 the Company terminated a lease of parking spaces and derecognized the relating right of use asset and the lease liability which were insignificant. In the year ended December 31, 2019 the Company terminated a lease of office space and derecognized the relating right of use asset and the lease liability of $0.2 million.

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


		Year ended		Year ended
	Income statement location	December 31, 2020		December 31, 2019
Operating lease expenses	Research and development expenses	$	1,654	$	1,108
	General and administrative expenses		376		712
Finance lease amortization expenses	Research and development expenses		395		350
	General and administrative expenses		21		14
Interest on finance lease liabilities	Interest expenses		8		9
Sublease income	Other income (expense)		(155)		(128)
Net lease expense		$	2,299	$	2,065

Rent expense under operating leases for the year ended December 31, 2018 was $1.1 million.

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


	December 31, 2020
	Operating lease		Finance lease		Total
2021		1,969		150		2,119
2022		1,967		133		2,100
2023		1,952		130		2,082
2024		130		11		141
2025		—		—		—
Thereafter		—		—		—
Total lease payments		6,018		424		6,442
Less: interest		201		11		212
Present value of lease liabilities	$	5,817	$	413	$	6,230

These annual minimum lease payments does not include the embedded lease obligations under service agreements, which commenced in the year ended December 2019.

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


	December 31,		December 31,
	2020		2019
Weighted average remaining lease term in years	3.1		4.1
Weighted average discount rate (1)	2.3	%	2.3	%

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

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


	December 31,		December 31,
	2020		2019
Weighted average remaining lease term in years	3.0		3.9
Weighted average discount rate (1)	1.7	%	1.7	%

(1) The contracts are concluded in euros. The discount rate was determined on a currency-equivalent basis.

The Company subleases certain of its leased real estate that it does not currently utilize to a third party. In December 2020, the Company agreed to extend the sublease by six weeks. The sublease has a remaining lease terms of 0.3 years without an option to renew and has been qualified as an operating lease. The Company recognizes sublease income in its consolidated statements of operations and comprehensive loss. The Company continued to account for the head lease as it did before sublease commencement.

Accrued expenses and other current liabilities

12 Months Ended

Dec. 31, 2020

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):


	December 31,		December 31,
	2020		2019
Consulting fees	$	527	$	724
Salaries and bonuses		4,381		2,640
Social security contributions		211		177
Unearned grant income (current)		878		725
Loans		—		1,224
Invoices not yet received		1,002		2,673
Finance lease liabilities		155		159
Other accruals and liabilities		232		84
	$	7,386	$	8,406

Loans payable

12 Months Ended

Dec. 31, 2020

Loans payable

Loans payable

8. Loans payable

As of December 31, 2020 and December 31, 2019, loans payable consisted of the following (in thousands):


	December 31,		December 31,
	2020		2019
Loans from FFG	$	6,564	$	7,305
Unamortized debt discount		(2,027)		(2,586)
Total Loans payable, net	$	4,537	$	4,719

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 rates ranging from 0.75% to 1.0% per annum and mature at various dates between June 2022 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.

The Company recognized grant income of $0.7 million, $0.8 million and $0.7 million during the years ended December 31, 2020, 2019 and 2018, respectively, related to the recognition of the unearned income recorded for the imputed benefit of FFG Loans at below-market interest rates. Unearned income (current) related to the imputed benefit of FFG Loans at below-market interest rates was $0.9 million, $0.7 million and $0.8 million as of December 31, 2020, 2019 and 2018, respectively, and unearned income (non-current) presented under loans payable non-current related to such benefit was $1.1 million, $1.9 million and $3.0 million as of December 31, 2020, 2019 and 2018, respectively.

In addition, the Company has recorded a discount to the carrying value of each FFG Loan for the portion of the loan proceeds allocated to grant funding, which is being amortized to interest expense over the term of the loan using the effective interest method. As of December 31, 2020 and 2019, the unamortized debt discount related to FFG Loans was $2.0 million and $2.6 million, respectively.

The Company recognized interest expense of $0.8 million, $0.9 million and $0.8 million during the years ended December 31, 2020, 2019 and 2018, respectively, related to the FFG Loans, which included interest expense related to the amortization of debt discount of $0.7 million, $0.8 million and $0.7 million during the years ended December 31, 2020, 2019 and 2018, respectively. A principal payment of $1.3 million and $0.8 million was made in the years ended December 31, 2020 and 2019, respectively.

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

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

In November 2019, the Company agreed an earlier repayment schedule for $3.3 million of the outstanding loans with FFG. As a result of the change, the Company reduced the deferred income attributable to the imputed benefit from below market interest by $0.3 million and increased the carrying value of the loans by the same amount. The change had no effect on the income of the year ended December 31, 2019 and the effect on the aggregate future cash flows under the loans is immaterial.

As of December 31, 2020, the aggregate minimum future principal payments due in connection with the FFG Loans are summarized as follows (in thousands):


Year ending December 31,	Amount
2021		—
2022		3,300
2023		1,968
2024		1,296
Thereafter		—
Total	$	6,564

Redeemable convertible preferred stock

12 Months Ended

Dec. 31, 2020

Redeemable convertible preferred stock.

Redeemable convertible preferred stock

9. Redeemable convertible preferred stock

Redeemable convertible preferred stock

The Company previously issued Series A redeemable convertible preferred stock (the "Series A Preferred Stock"), Series B redeemable convertible preferred stock (the "Series B Preferred Stock"), Series C redeemable convertible preferred stock (the "Series C Preferred Stock") and Series D redeemable convertible preferred stock (the "Series D Preferred Stock"). Upon the closing of the Company’s IPO in April 2019, the Company’s outstanding redeemable convertible preferred stock automatically converted into shares of common stock or, if elected by the holder, into Class A common stock. Prior to conversion, the Preferred Stock had certain contingent redemption features based upon the occurrence of events that were not solely within the control of the Company and was therefore classified as mezzanine equity.

In February 2019, the Company issued and sold 257,000 shares of Series D Preferred Stock at an average price of $145.65 per share for gross proceeds of $37.4 million. The Company incurred issuance costs in connection with the Series D Preferred Stock of $0.2 million.

Upon issuance of each class of Preferred Stock, the Company assessed the embedded conversion and liquidation features of the shares and determined that such features did not require the Company to separately account for these features. The Company also concluded that no beneficial conversion feature existed on the issuance date of each class of Preferred Stock.

Upon the closing of the Company’s IPO, on April 23, 2019, all 1,580,506 then outstanding shares of Preferred Stock converted into 14,582,161 shares of common stock and 3,819,732 shares of Class A common stock. The related carrying value of $142.0 million was reclassified to common stock and additional paid-in capital.

Prior to the IPO, the shares of Preferred Stock consisted of the following (in thousands, except share amounts):


		Preferred
	Preferred	shares			Common stock
	shares	issued and	Carrying		issuable upon
	authorized	outstanding	value		conversion
Series A Preferred Stock	137,814	137,814	$	0.014	1,604,574
Series B Preferred Stock	492,192	492,192		0.049	5,730,612
Series C Preferred Stock	693,500	693,500		0.069	8,074,447
Series D Preferred Stock	257,000	257,000		0.026	2,992,260
	1,580,506	1,580,506	$	0.158	18,401,893

Prior to the conversion of the Preferred Stock upon closing of the IPO, the rights, preferences, and privileges of the Preferred Stock were as follows:

Conversion

Each share of Preferred Stock was convertible, at the option of the holder, at any time, and without the payment of additional consideration, into 11.643 fully paid and non-assessable shares of common stock or non-voting Class A common stock as determined by dividing the original issue price paid for such Preferred Shares by the applicable conversion price in effect at the time of conversion.

Liquidation

In the event of any voluntary or involuntary liquidation, dissolution or winding up of the Company or certain deemed liquidation events, the holders of Preferred Shares had a right to receive, certain amounts in preference to any distribution to the holders of common stock.

Common stock, Class A common stock and convertible preferred stock	12 Months Ended
	Dec. 31, 2020
Common stock, Class A common stock and convertible preferred stock
Common stock, Class A common stock and convertible preferred stock	10. 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 December 31, 2020, the Company was authorized to issue 100,000,000 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. As of December 31, 2020, the Company had 25,948,712 shares of common stock, 3,819,732 shares of Class A common stock and 2,978 shares of preferred stock outstanding and issued. On April 23, 2019, the Company closed its IPO of 6,000,000 shares of common stock, at an offering price to the public of $14.00 per share. The Company received net proceeds of $74.6 million, after deducting $9.4 million in underwriting discounts and commissions and offering expenses. Upon the closing of the Company’s IPO all then outstanding shares of Preferred Stock converted into 14,582,161 shares of common stock and 3,819,732 shares of Class A common stock. On December 11, 2020, the Company closed a public offering of 3,910,000 shares of its common stock, which included the full exercise of the underwriters’ option to purchase additional shares and of 2,978 shares of Series A convertible preferred stock at a public offering price of $11.75 and $11,750.00 per share, respectively, for net proceeds of $75.0 million after deducting underwriting discounts and commissions and offering expenses. 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 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 convertible preferred stock has the right to convert each share of Series A 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 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 our 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 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 our 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 preferred stock will receive a payment equal to $0.001 per share of Series A 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.

Stock-based compensation

12 Months Ended

Dec. 31, 2020

Stock-based compensation

Stock-based compensation

11. Stock-based compensation

2018 Stock Option and Grant Plan

In connection with a transaction between entities under common control by which the Company became the reporting entity in June 2018, the Board of Directors approved the 2018 Stock Option and Grant Plan, by which options granted by the previous reporting entity under the 2016 Stock Option Plan and outstanding at the time of the effectiveness of the transaction were replaced at similar commercial terms. In the accompanying consolidated financial statements and notes, options issued under previous stock option plans and respective compensation expenses are retrospectively presented as if such options had been issued and outstanding under the 2018 Stock Option and Grant Plan for all periods during which the previous reporting entity was under common control.

The exercise price for options granted as a replacement of the 2016 Stock Option Plan is the U.S. dollar equivalent of €0.09, except for 23,286 options granted to an US employee, for which the exercise price is $2.93 following a repricing of these options in December 2018. For any new options, the exercise price shall not be less than 100% of the fair market value of the common stock on the grant date.

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 10th anniversary of the grant date. As of December 31, 2020, 1,097,809 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 3,630,686 shares which shall be cumulatively increased each year by up to 4.0% 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 10th 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 of 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, on a weighted average basis, the assumptions used in the Black-Scholes option-pricing model for estimating the fair value of stock options granted during:


	Year ended
	Year ended December 31,
	2020		2019		2018

Risk-free interest rate	0.44	%	2.21	%	2.78	%
Expected term (in years)	6.1		6.1		5.1
Expected volatility	80.2	%	74.2	%	72.1	%
Expected dividends	—	%	—	%	—	%

For the 2019 and 2020 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, 2020 (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, 2019	2,999,284	$	7.63	8.1	$	15,840
Granted	890,904		8.95
Exercised	(255,011)		0.25
Forfeited	(79,232)		9.63
Outstanding as of December 31, 2020	3,555,945	$	8.45	7.9	$	12,839

Options exercisable as of December 31, 2020	1,459,479	$	6.01	7.0	$	8,668
Options unvested as of December 31, 2020	2,096,466	$	10.13	8.6	$	4,171

The aggregate intrinsic value of stock options was calculated as the difference between the exercise price of the stock options and the estimated 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 estimated fair value per common stock used for calculating the intrinsic values as of December 31, 2020, December 31, 2019 and December 31, 2018, was $11.09, $12.23 and $10.33, respectively.

The aggregate intrinsic value of options exercised during the years ended December 31, 2020, 2019 and 2018 was $2.9 million, $1.4 million and $1.0 million, respectively.

The weighted average grant-date fair value per share of stock options granted during the years ended December 31, 2020, 2019 and 2018 was $8.95, $7.92 and $2.55, respectively.

The total fair value of stock options vested during the years ended December 31, 2020 and 2019 was $5.6 million and $0.9 million, respectively.

Cash received from stock option exercise under share-based payment arrangements for the years ended December 31, 2020, 2019 and 2018 was $63 thousand, $16 thousand and $9 thousand, respectively.

Restricted Stock Units

In the year ended December 31, 2020, the Company granted restricted stock units with time-based vesting conditions to officers, employees and a consultant to compensate them for a temporary salary or fee reduction in response to the coronavirus pandemic. The restricted stock units are subject to time-based vesting conditions and generally vest in four equal installments between March 2021 and November 2021. The Company measures the fair value of restricted stock units on the date of grant using the grant date market price of the underlying shares. Expenses are recorded using the graded-vesting method. The table below summarizes the Company’s restricted stock unit activity since December 31, 2019:


		Weighted
		Average Grant
	Number of	Date Fair
	Shares	Value
Outstanding as of December 31, 2019	—	$	—
Granted	44,760		11.87
Vested	(1,060)		11.89
Forfeited	—		—
Outstanding as of December 31, 2020	43,700	$	11.87

The total fair value of restricted stock vested during the year ended December 31, 2020 was insignificant. The Company had no restricted stock outstanding in the years ended 2019 and 2018.

Common Stock Awards

In the year ended December 31, 2020, the Company issued 36,249 unrestricted shares of common stock to the non-executive members of its Board of Directors. The Company’s directors have accepted to receive equity instead of cash as their 2020 board remuneration as part of the Company’s response to the coronavirus pandemic. The total fair value of common stock awards issued during the year ended December 31, 2020 was $0.3 million. The grant date fair value per share of common stock was $9.56 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 year ended December 31, 2020.

In the years ended 2019 and 2018, the Company has not issued common stock awards.

Stock-based compensation

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


	Year ended December 31,
	2020		2019		2018
Research and development expenses	$	3,084	$	1,981	$	399
General and administrative expenses		5,573		3,584		468
	$	8,657	$	5,565	$	867

In the year ended December 31, 2018, the terms of 2,000 outstanding stock options were modified to increase the exercise price from $1.17 to $34.12. The Company determined that the fair value of the modified award on the effective date of the modification was smaller than the fair value of the original award immediately before the modification. Therefore, the modification did not lead to recognition of additional compensation cost or a change in unrecognized compensation cost.

As of December 31, 2020 and 2019, total unrecognized compensation cost related to the unvested stock-based awards was $6.5 million and $9.3 million, respectively, which is expected to be recognized over weighted average periods of 1.6 and 1.8 years, respectively.

Income taxes

12 Months Ended

Dec. 31, 2020

Income taxes

Income taxes

12. Income taxes

During the years ended December 31, 2020, 2019 and 2018, the Company recorded no income tax benefits for the net operating losses incurred in each year, due to its uncertainty of realizing a benefit from those items. The Company's losses before income taxes were generated in the United States and Austria.

For financial reporting purposes, losses before income taxes for the years ended December 31, 2020, 2019 and 2018 consisted of the following (in thousands):


	Year ended December 31,
	2020		2019		2018
United States	$	(11,603)	$	(7,886)	$	(604)
Foreign (Austria)		(32,479)		(35,151)		(15,609)
Net loss before tax	$	(44,082)	$	(43,037)	$	(16,213)

The Company's worldwide effective tax rate for the years ended December 31, 2020, 2019 and 2018 was 0.0%, 0.0% and (0.1)%, respectively. The tax rate is affected by recurring items, such as tax rates in foreign jurisdictions and the relative amounts of income earned in those jurisdictions, which is expected to be fairly consistent in the near term. It is also affected by discrete items that may occur in any given year, but are not consistent from year to year. The following items had the most significant impact on the difference between the statutory U.S. federal income tax rate of 21% for the years ended December 31, 2020, 2019 and 2018 and the effective tax rate:


	Year ended December 31,
	2020			2019			2018
U.S. federal statutory income tax rate		(21.0)	%		(21.0)	%		(21.0)	%
State income taxes, net of federal benefit		—			—			—
Foreign tax rate differential(1)		(4.0)			(4.0)			(4.0)
Not taxable government grants(2)		(4.7)			(5.4)			(7.5)
Stock-based compensation(3)		(1.0)			(0.3)			(4.6)
other		0.5			(0.3)			(0.5)
Change in deferred tax asset valuation allowance(4)		30.2			31.0			37.5
Effective income tax rate		—	%		—	%		(0.1)	%

(1) The 4% increase for the years ended December 31, 2020, 2019 and 2018, respectively, resulted from tax rate differences between U.S. and non-U.S. jurisdictions. Net loss before tax was principally generated in Austria, where the statutory tax rate is 25%.

(2) For the years ended December 31, 2020, 2019 and 2018, 4.7%, 5.4% and 7.5% increase, respectively, resulted from non-taxable research subsidies received from Austrian government agencies.

(3) For the years ended December 31, 2020, 2019 and 2018, 1.0% increase, 0.3% increase and 4.6% increase, respectively, resulted from non-taxable Stock-based compensation expense.

(4) For the years ended December 31, 2020, 2019 and 2018, 30.2% reduction, 31.0% reduction and 37.5% reduction, respectively, resulted from changes in valuation allowance on deferred tax assets. Deferred tax assets will only be recovered when the generation of future taxable income is more likely than not. Due to the nature of the Company's research activities and the inherent uncertainties the deferred tax assets have been fully impaired.

Components of the net deferred tax assets or liabilities as of the years ended December 31, 2020 and 2019 consisted of the following (in thousands):


	Year ended December 31,
	2020		2019
Deferred tax assets:
Net operating loss carryforwards	$	43,563	$	29,180
Credit carryforwards		64		180
Accrued expenses and other		(36)		669
Stock-based compensation		2,725		2,717
Operating lease liabilities		1,513		1,740
Finance lease liabilities		103		132
Total deferred tax assets		47,932		34,618
Valuation allowance		(46,064)		(32,583)
Total deferred tax assets		1,868		2,035

Deferred tax liabilities:
Operating lease right of use asset		(1,614)		(1,808)
Finance lease right of use asset		(254)		(227)
Total deferred tax liabilities		(1,868)		(2,035)

Net deferred tax assets	$	—	$	—

As of December 31, 2020, 2019 and 2018, the Company had Austrian net operating loss carryforwards of $163.2 million, $112.3 million and $76.0 million, respectively, with no expiry date. The Company has evaluated the positive and negative evidence bearing upon its ability to realize the deferred tax assets. 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 December 31, 2020, 2019 and 2018. Management reevaluates the positive and negative evidence at each reporting period.

The amount of the deferred tax asset considered realizable, however, could be adjusted if estimates of future taxable income during the carryforward period are reduced or increased or if objective negative evidence in the form of losses is no longer present and additional weight may be given to subjective evidence. The tax years in which the tax carryforwards were generated may still be adjusted upon examination by the tax authorities.

Changes in the valuation allowance for deferred tax assets during the years ended December 31, 2020, 2019 and 2018 related primarily to the increases in net operating loss carryforwards as follows (in thousands):


	Year ended December 31,
	2020		2019		2018
Valuation allowance at beginning of period	$	(32,583)	$	(19,156)	$	(13,789)
Increases		(13,481)		(13,427)		(5,367)
Valuation allowance at end of period	$	(46,064)	$	(32,583)	$	(19,156)

On December 22, 2017, the United States enacted the Tax Cuts and Jobs Act (“Tax Reform Legislation” or “TCJA”), which made significant changes to U.S. federal income tax code, including a reduction of the statutory corporate tax rate from 35% to 21%, effective on January 1, 2018. This new legislation also eliminated or reduced certain corporate income tax deductions as well as introduced new provisions that taxed certain foreign income not previously taxed in the United States. The TCJA also includes a provision for a tax on all previously undistributed earnings of U.S. companies located in foreign jurisdictions. Undistributed earnings in the form of cash and cash equivalents is taxed at a rate of 15.5% and all other earnings are taxed at a rate of 8.0%. This tax is payable over 8 years and will not accrue interest.

The Tax Reform Legislation introduced section 951A, a new tax on so-called "global intangible low-taxed income," or “GILTI”. GILTI applies to income of a controlled foreign corporation (“CFC”) that is not otherwise subpart F income, and consists of the excess "tested income" over a 10% return on the CFC's “qualified business asset investment,” or “QBAI”. QBAI is the total tax basis of the CFC's depreciable, tangible property used in the production of tested income. The full amount of GILTI is included in taxable income. The GILTI inclusion is then reduced by 50% (reduced to 37.5% after 2025). However, that reduction in GILTI may be limited based on the level of U.S. taxable income. A limited allowance for foreign tax credits is allowed that would reduce the U.S. tax cost. GILTI foreign tax credits can only reduce U.S. taxes owed on GILTI and are not eligible for carryforward. The Company's Austrian subsidiary falls under the category of a CFC and due to the nature of its business model as a technology company, there may not be a material amount of tangible assets if this subsidiary starts to generate profits. GILTI taxation therefore may be applicable.

Due to its loss making situation, the Company has established a full valuation allowance against its deferred tax assets as of December 31, 2020, 2019 and 2018 and the changes under the Tax Reform Legislation therefore did not have an effect on its deferred tax assets and liabilities and deferred tax asset valuation allowances in the period the tax regimen change was enacted.

The Company files income tax returns in the U.S. federal jurisdiction as well as in New York. The tax years from 2018 to present remain open to examination by the jurisdictions in which the Company is subject to tax. There are currently no pending income tax examinations in the U.S. Furthermore, the Company files income tax returns in Austria. The tax years 2015 to present remain open to examination by the jurisdiction. As of December 31, 2020, there were income and value added tax examinations pending for the years 2015 to 2018 in Austria.

The Company evaluates tax positions for recognition using a more likely than not recognition threshold, and those tax positions eligible for recognition are measured as the largest amount of tax benefit that is greater than 50% likely of being realized upon the effective settlement with a taxing authority that has full knowledge of all relevant information. As of December 31, 2020, the Company had no unrecognized income tax benefits that would affect the Company’s effective tax rate if recognized.

- Definition

The entire disclosure for income 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 + Details

Commitments and contingencies	12 Months Ended
Commitments and contingencies	Dec. 31, 2020
Commitments and contingencies
Commitments and contingencies	13. Commitments and contingencies Contract manufacturing arrangements The Company has entered into arrangements with contract manufacturing organizations (“CMOs”) for manufacturing of materials for research and development purposes, including manufacturing of clinical trial materials. These contracts generally provide for non-cancellable obligations or cancellation penalties depending on the time of cancellation. As of December 31, 2020, the Company’s total non-cancellable obligations under contracts with CMOs, excluding embedded lease liabilities, were $11.9 million, which relate to 2021 deliverables. In December 2018, the Company entered into an agreement with a contract manufacturing organization for the production of clinical trial material, including seed lots, drug substance for toxicology studies, stability studies and clinical studies as well as related technology transfer, quality control and process optimization activities which commenced in February 2019. Under the financial terms of the agreement the Company is obliged to pay non-cancellable minimum service fees totaling $13.9 million through 2021. The Company has determined that the agreement includes embedded leases which resulted in recognition of operating and finance lease assets and corresponding liabilities on the Consolidated Balance Sheet. Intellectual property licenses The Company has entered into certain license agreements under which it is obligated to make milestone payments upon the achievement of certain development and regulatory milestones, to pay royalties on net sales of licensed products, and to pay a percentage of the sublicense fees which the Company receives from its sublicensees. In the years ended December 31, 2020, 2019 and 2018, the Company recorded $1.2 million, $1.9 million and $0.1 million, respectively, in licensing fees from intellectual property licenses as research and development expenses. These amounts mainly 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 consolidated financial statements as of December 31, 2020 and December 31, 2019. 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. 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 any asserted or un-asserted legal claims or proceedings, individually or in the aggregate, will have a material adverse effect on the Company. The Company expenses the costs related to such legal proceedings as incurred.

401(k) Savings Plan	12 Months Ended
401(k) Savings Plan	Dec. 31, 2020
401(k) Savings Plan
401(k) Savings Plan	14. 401(k) Savings Plan The Company established a defined contribution savings plan under Section 401(k) of the Internal Revenue Code. This plan provides that eligible employees can elect to contribute to the 401(k) Plan, subject to certain limitations, on a pretax basis. The Company matches up to 100% of the first 4% of each employee’s contribution. During the year ended December 31, 2020, expenses recognized for the 401(k) Plan were $0.2 million. During the years ended December 31, 2019 and 2018, expenses recognized for the 401(k) Plan were insignificant.

- Definition

The entire disclosure for retirement benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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-Name Accounting Standards Codification
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+ Details

Net loss per share

12 Months Ended

Dec. 31, 2020

Net loss per share

Net loss per share

15. 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):


	Year ended December 31,
	2020		2019		2018
Numerator:
Net loss	$	(44,082)	$	(43,037)	$	(16,237)

Denominator:
Weighted-average common shares outstanding, basic and diluted		25,876,376		17,859,935		914,375
Weighted-average Series A convertible preferred shares outstanding, basic and diluted, presented as if converted into common stock1)		162,732		—		—
Total number of shares used to calculate net loss per share, basic and diluted		26,039,108		17,859,935		914,375

Net loss per share, basic and diluted	$	(1.69)	$	(2.41)	$	(17.76)

(1) Series A convertible preferred stock are participating securities that have substantially the same terms and features as the Company’s common stock. Series A 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 convertible preferred stock is convertible into 1,000 shares of common stock. 2,978,000 shares of the Company’s common stock are issuable upon conversion of Series A convertible preferred stock (see Note 10).

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 (upon conversion) that were not included in the diluted per share calculations because they would be anti-dilutive were as follows:


	Year ended December 31,
	2020	2019	2018

Series A Preferred Stock	—	—	1,604,574
Series B Preferred Stock	—	—	5,730,612
Series C Preferred Stock	—	—	8,074,447
Series D Preferred Stock	—	—	—
Options issued and outstanding	3,555,945	2,999,284	1,606,325
Unvested restricted stock units	43,700	—	—
Total	3,599,645	2,999,284	17,015,958

Related parties	12 Months Ended
Related parties	Dec. 31, 2020
Related parties
Related parties	16. Related parties Following the expiry of the consultancy agreement between the Company and its Chief Scientific Officer, Daniel Pinschewer, on March 19, 2020 the Company entered into a new consultancy agreement with Daniel Pinschewer on March 20, 2020, pursuant to which he serves as Scientific Advisor to the Chief Executive Officer. The Company is party to research and service arrangements with the University of Basel. Daniel Pinschewer, formerly Chief Scientific Officer, and his spouse are employees of the University of Basel and both involved in providing the services under these arrangements. In the years ended December 31, 2020, 2019 and 2018, the Company recorded $0.3 million, $0.3 million and $0.4 million, respectively, in research and development expenses for service fees paid to the University of Basel. Payments to the University of Basel during Daniel Pinschewer’s term as Chief Scientific Officer were reported as related party transactions but payments following the expiry of that role in March 2020 were no longer considered related party transactions. The University of Basel is also entitled to receive de minimis royalties on the net sales of any product that is based on a patent created by the Company’s Scientific Advisor to the Chief Executive Officer in the course of his consulting services to the Company. In the years ended December 31, 2020, 2019 and 2018, no royalties were paid pursuant to the terms of this arrangement. During the year ended December 31, 2019, the Company issued 50,670 shares of Series D Preferred Stock for total gross proceeds of $7.4 million and 1,303,750 shares of common stock as part of the Company’s IPO for total gross proceeds of $18.3 million to certain stockholders that were related parties.

Selected Quarterly Financial information (unaudited)

12 Months Ended

Dec. 31, 2020

Selected Quarterly Financial Information (Unaudited)

Selected Quarterly Financial Information (Unaudited)

17. Selected Quarterly Financial Information (Unaudited)

The following information has been derived from unaudited condensed consolidated financial statements that, in the opinion of management, include all recurring adjustments necessary for a fair statement of such information (in thousands except per share data) for the years ended December 31, 2020 and 2019 are as follows:



	2020 Quarter Ended
	March 31,		June 30,		September 30,		December 31,
Revenue	$	3,696	$	6,685	$	4,040	$	5,163
Operating expenses		(16,155)		(15,911)		(20,446)		(20,357)
Net loss		(10,926)		(7,092)		(13,589)		(12,475)
Net loss per share - basic and diluted	$	(0.43)	$	(0.28)	$	(0.53)	$	(0.46)



	2019 Quarter Ended
	March 31,		June 30,		September 30,		December 31,
Revenue	$	2,235	$	4,051	$	2,038	$	3,618
Operating expenses		(12,890)		(17,680)		(15,614)		(16,843)
Net loss		(9,329)		(12,079)		(11,385)		(10,244)
Net loss per share - basic and diluted	$	(9.27)	$	(0.63)	$	(0.45)	$	(0.40)

Summary of significant accounting policies (Policies)

12 Months Ended

Dec. 31, 2020

Summary of significant accounting policies

Basis of presentation

Stock split

Transaction between entities under common control

Going concern

Use of estimates

Foreign currency and currency translation

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

Concentrations of credit risk and of significant suppliers

Cash equivalents

Deferred offering costs

Fair value measurements

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

The Company’s cash equivalents are carried at fair value, determined according to the fair value hierarchy described above (see Note 4).

Property and equipment


		Estimated useful life
Leasehold improvements		5 years
Laboratory equipment		3 - 10 years
Furniture and fixtures		3 - 10 years
Computer equipment and software		3 - 4 years

Leases

Capitalized Software Development Cost

Impairment of long-lived assets

Segment information

Revenue recognition from contracts with customers

Upfront payment

Reimbursement for services

Research and development milestones

Sales-based milestones and royalty payments

Cost to fulfill contracts

Research and development costs

Research and manufacturing contract costs and accruals

Government grant agreements and research incentives

Redeemable convertible preferred stock

Stock-based compensation

Comprehensive loss

Net loss per share

The Company reported a net loss attributable to common stockholders for the years ended December 31, 2020, 2019 and 2018.

Income Taxes.

Income taxes

Recent accounting pronouncements

Adopted as of current period

Recently Issued Accounting Pronouncements

Summary of significant accounting policies (Tables)

12 Months Ended

Dec. 31, 2020

Summary of significant accounting policies

Schedule of estimated useful life of each asset


		Estimated useful life
Leasehold improvements		5 years
Laboratory equipment		3 - 10 years
Furniture and fixtures		3 - 10 years
Computer equipment and software		3 - 4 years

Fair Value of Financial Assets (Tables)

12 Months Ended

Dec. 31, 2020

Fair Value of Financial Assets

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


	Fair Value Measurement at December 31, 2020 Using
	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	35,397	$	—	$	—	$	35,397
Total	$	35,397	$	—	$	—	$	35,397


	Fair Value Measurement at December 31, 2019 Using
	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	35,132	$	—	$	—	$	35,132
Total	$	35,132	$	—	$	—	$	35,132

Property and equipment, net (Tables)

12 Months Ended

Dec. 31, 2020

Property and equipment, net

Schedule of property and equipment, net

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


	Year ended December 31,
	2020		2019

Leasehold improvements	$	3,322	$	1,919
Construction in progress		28		286
Laboratory equipment		5,982		4,555
Furniture and fixtures		430		524
Computer equipment and software		1,554		923
Property and equipment, gross		11,316		8,207
Less: Accumulated depreciation		(5,097)		(3,081)
Property and equipment, net	$	6,219	$	5,126

Leases (Tables)

12 Months Ended

Dec. 31, 2020

Leases

Schedule of operating and finance leases presentation in the consolidated balance sheets


		December 31,		December 31,
	Balance sheet location	2020		2019
Assets
Operating lease assets, net	Operating lease right of use assets	$	6,452	$	7,875
Finance lease assets, net	Finance lease right of use assets		1,298		1,602
Total lease assets			7,750		9,477
Liabilities
Current operating lease liability	Operating lease liabilities, current		1,998		1,814
Current finance lease liability	Accrued expenses and other current liabilities		155		159
Total current lease liabilities			2,153		1,973
Non-current operating lease liability	Operating lease liabilities, non-current		3,819		5,290
Non-current finance lease liability	Other non-current liabilities		258		367
Total non-current lease liabilities			4,077		5,657
Total lease liabilities		$	6,230	$	7,630

Summary of the effect of lease costs


		Year ended		Year ended
	Income statement location	December 31, 2020		December 31, 2019
Operating lease expenses	Research and development expenses	$	1,654	$	1,108
	General and administrative expenses		376		712
Finance lease amortization expenses	Research and development expenses		395		350
	General and administrative expenses		21		14
Interest on finance lease liabilities	Interest expenses		8		9
Sublease income	Other income (expense)		(155)		(128)
Net lease expense		$	2,299	$	2,065

Summary of maturities of operating lease liabilities


	December 31, 2020
	Operating lease		Finance lease		Total
2021		1,969		150		2,119
2022		1,967		133		2,100
2023		1,952		130		2,082
2024		130		11		141
2025		—		—		—
Thereafter		—		—		—
Total lease payments		6,018		424		6,442
Less: interest		201		11		212
Present value of lease liabilities	$	5,817	$	413	$	6,230

Summary of maturities of finance lease liabilities


	December 31, 2020
	Operating lease		Finance lease		Total
2021		1,969		150		2,119
2022		1,967		133		2,100
2023		1,952		130		2,082
2024		130		11		141
2025		—		—		—
Thereafter		—		—		—
Total lease payments		6,018		424		6,442
Less: interest		201		11		212
Present value of lease liabilities	$	5,817	$	413	$	6,230

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


	December 31,		December 31,
	2020		2019
Weighted average remaining lease term in years	3.0		3.9
Weighted average discount rate (1)	1.7	%	1.7	%

(1) The contracts are concluded in euros. The discount rate was determined on a currency-equivalent basis.

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


	December 31,		December 31,
	2020		2019
Weighted average remaining lease term in years	3.1		4.1
Weighted average discount rate (1)	2.3	%	2.3	%

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

Accrued expenses and other current liabilities (Tables)

12 Months Ended

Dec. 31, 2020

Accrued expenses and other current liabilities

Schedule of accrued expenses and other current liabilities

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


	December 31,		December 31,
	2020		2019
Consulting fees	$	527	$	724
Salaries and bonuses		4,381		2,640
Social security contributions		211		177
Unearned grant income (current)		878		725
Loans		—		1,224
Invoices not yet received		1,002		2,673
Finance lease liabilities		155		159
Other accruals and liabilities		232		84
	$	7,386	$	8,406

Loans payable (Tables)

12 Months Ended

Dec. 31, 2020

Loans payable

Schedule of loans payable

As of December 31, 2020 and December 31, 2019, loans payable consisted of the following (in thousands):


	December 31,		December 31,
	2020		2019
Loans from FFG	$	6,564	$	7,305
Unamortized debt discount		(2,027)		(2,586)
Total Loans payable, net	$	4,537	$	4,719

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

As of December 31, 2020, the aggregate minimum future principal payments due in connection with the FFG Loans are summarized as follows (in thousands):


Year ending December 31,	Amount
2021		—
2022		3,300
2023		1,968
2024		1,296
Thereafter		—
Total	$	6,564

Redeemable convertible preferred stock (Tables)

12 Months Ended

Dec. 31, 2020

Redeemable convertible preferred stock.

Schedule of Preferred Stock

Prior to the IPO, the shares of Preferred Stock consisted of the following (in thousands, except share amounts):


		Preferred
	Preferred	shares			Common stock
	shares	issued and	Carrying		issuable upon
	authorized	outstanding	value		conversion
Series A Preferred Stock	137,814	137,814	$	0.014	1,604,574
Series B Preferred Stock	492,192	492,192		0.049	5,730,612
Series C Preferred Stock	693,500	693,500		0.069	8,074,447
Series D Preferred Stock	257,000	257,000		0.026	2,992,260
	1,580,506	1,580,506	$	0.158	18,401,893

Stock-based compensation (Tables)

12 Months Ended

Dec. 31, 2020

Stock-based compensation

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


	Year ended
	Year ended December 31,
	2020		2019		2018

Risk-free interest rate	0.44	%	2.21	%	2.78	%
Expected term (in years)	6.1		6.1		5.1
Expected volatility	80.2	%	74.2	%	72.1	%
Expected dividends	—	%	—	%	—	%

Schedule of summary of stock option activity

The following table summarizes the Company’s stock option activity since January 1, 2020 (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, 2019	2,999,284	$	7.63	8.1	$	15,840
Granted	890,904		8.95
Exercised	(255,011)		0.25
Forfeited	(79,232)		9.63
Outstanding as of December 31, 2020	3,555,945	$	8.45	7.9	$	12,839

Options exercisable as of December 31, 2020	1,459,479	$	6.01	7.0	$	8,668
Options unvested as of December 31, 2020	2,096,466	$	10.13	8.6	$	4,171

Schedule of summary of restricted stock unit activity


		Weighted
		Average Grant
	Number of	Date Fair
	Shares	Value
Outstanding as of December 31, 2019	—	$	—
Granted	44,760		11.87
Vested	(1,060)		11.89
Forfeited	—		—
Outstanding as of December 31, 2020	43,700	$	11.87

Schedule of stock-based compensation expense

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


	Year ended December 31,
	2020		2019		2018
Research and development expenses	$	3,084	$	1,981	$	399
General and administrative expenses		5,573		3,584		468
	$	8,657	$	5,565	$	867

Income taxes (Tables)

12 Months Ended

Dec. 31, 2020

Income taxes

Schedule of losses before income taxes

For financial reporting purposes, losses before income taxes for the years ended December 31, 2020, 2019 and 2018 consisted of the following (in thousands):


	Year ended December 31,
	2020		2019		2018
United States	$	(11,603)	$	(7,886)	$	(604)
Foreign (Austria)		(32,479)		(35,151)		(15,609)
Net loss before tax	$	(44,082)	$	(43,037)	$	(16,213)

Schedule of effective income tax rate reconciliation


	Year ended December 31,
	2020			2019			2018
U.S. federal statutory income tax rate		(21.0)	%		(21.0)	%		(21.0)	%
State income taxes, net of federal benefit		—			—			—
Foreign tax rate differential(1)		(4.0)			(4.0)			(4.0)
Not taxable government grants(2)		(4.7)			(5.4)			(7.5)
Stock-based compensation(3)		(1.0)			(0.3)			(4.6)
other		0.5			(0.3)			(0.5)
Change in deferred tax asset valuation allowance(4)		30.2			31.0			37.5
Effective income tax rate		—	%		—	%		(0.1)	%

(2) For the years ended December 31, 2020, 2019 and 2018, 4.7%, 5.4% and 7.5% increase, respectively, resulted from non-taxable research subsidies received from Austrian government agencies.

(3) For the years ended December 31, 2020, 2019 and 2018, 1.0% increase, 0.3% increase and 4.6% increase, respectively, resulted from non-taxable Stock-based compensation expense.

Components of the net deferred tax assets or liabilities

Components of the net deferred tax assets or liabilities as of the years ended December 31, 2020 and 2019 consisted of the following (in thousands):


	Year ended December 31,
	2020		2019
Deferred tax assets:
Net operating loss carryforwards	$	43,563	$	29,180
Credit carryforwards		64		180
Accrued expenses and other		(36)		669
Stock-based compensation		2,725		2,717
Operating lease liabilities		1,513		1,740
Finance lease liabilities		103		132
Total deferred tax assets		47,932		34,618
Valuation allowance		(46,064)		(32,583)
Total deferred tax assets		1,868		2,035

Deferred tax liabilities:
Operating lease right of use asset		(1,614)		(1,808)
Finance lease right of use asset		(254)		(227)
Total deferred tax liabilities		(1,868)		(2,035)

Net deferred tax assets	$	—	$	—

Changes in the valuation allowance for deferred tax assets


	Year ended December 31,
	2020		2019		2018
Valuation allowance at beginning of period	$	(32,583)	$	(19,156)	$	(13,789)
Increases		(13,481)		(13,427)		(5,367)
Valuation allowance at end of period	$	(46,064)	$	(32,583)	$	(19,156)

Net loss per share (Tables)

12 Months Ended

Dec. 31, 2020

Net loss per share

Schedule of basic and diluted net loss per share


	Year ended December 31,
	2020		2019		2018
Numerator:
Net loss	$	(44,082)	$	(43,037)	$	(16,237)

Denominator:
Weighted-average common shares outstanding, basic and diluted		25,876,376		17,859,935		914,375
Weighted-average Series A convertible preferred shares outstanding, basic and diluted, presented as if converted into common stock1)		162,732		—		—
Total number of shares used to calculate net loss per share, basic and diluted		26,039,108		17,859,935		914,375

Net loss per share, basic and diluted	$	(1.69)	$	(2.41)	$	(17.76)

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


	Year ended December 31,
	2020	2019	2018

Series A Preferred Stock	—	—	1,604,574
Series B Preferred Stock	—	—	5,730,612
Series C Preferred Stock	—	—	8,074,447
Series D Preferred Stock	—	—	—
Options issued and outstanding	3,555,945	2,999,284	1,606,325
Unvested restricted stock units	43,700	—	—
Total	3,599,645	2,999,284	17,015,958

Selected Quarterly Financial Information (unaudited) (Tables)

12 Months Ended

Dec. 31, 2020

Selected Quarterly Financial Information (Unaudited)

Schedule of selected quarterly financial information (unaudited)



	2020 Quarter Ended
	March 31,		June 30,		September 30,		December 31,
Revenue	$	3,696	$	6,685	$	4,040	$	5,163
Operating expenses		(16,155)		(15,911)		(20,446)		(20,357)
Net loss		(10,926)		(7,092)		(13,589)		(12,475)
Net loss per share - basic and diluted	$	(0.43)	$	(0.28)	$	(0.53)	$	(0.46)



	2019 Quarter Ended
	March 31,		June 30,		September 30,		December 31,
Revenue	$	2,235	$	4,051	$	2,038	$	3,618
Operating expenses		(12,890)		(17,680)		(15,614)		(16,843)
Net loss		(9,329)		(12,079)		(11,385)		(10,244)
Net loss per share - basic and diluted	$	(9.27)	$	(0.63)	$	(0.45)	$	(0.40)

Summary of significant accounting policies - Stock split and Transaction between entities under common control (Details)		1 Months Ended
	Apr. 05, 2019	Jun. 30, 2018 shares
Summary of significant accounting policies
Stock split ratio	11.643
Hookipa Biotech AG \| Common stock
Summary of significant accounting policies
Issuance of shares (in shares)		78,311
Hookipa Biotech AG \| Redeemable Convertible Preferred Stock
Summary of significant accounting policies
Issuance of shares (in shares)		1,323,506

Summary of significant accounting policies - Going concern, Concentrations of credit risk and of significant suppliers, Cash equivalents and Deferred offering costs (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2020 USD ($) customer	Dec. 31, 2019 USD ($) customer	Dec. 31, 2018 USD ($) customer
Concentration Risk [Line Items]
Net losses \| $	$ 12,475	$ 13,589	$ 7,092	$ 10,926	$ 10,244	$ 11,385	$ 12,079	$ 9,329	$ 44,082	$ 43,037	$ 16,237
Accumulated deficit \| $	$ 147,101				$ 103,019				$ 147,101	$ 103,019
Customer Concentration Risk \| Accounts receivable
Concentration Risk [Line Items]
Number of customers \| customer									1	1
Customer Concentration Risk \| Sales
Concentration Risk [Line Items]
Number of customers \| customer									1	1	1

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
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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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-Name Accounting Standards Codification
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Reference 4: 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 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
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-Subparagraph (a)
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Subparagraph (f)
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721683-107760

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22595-107794

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 1B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669625-108580

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599

Reference 11: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(18))
-URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263

Reference 12: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(20))
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

Reference 13: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 15: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 16: http://www.xbrl.org/2003/role/disclosureRef
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Reference 17: http://www.xbrl.org/2003/role/disclosureRef
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Reference 18: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22583-107794

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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 20: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 21: http://www.xbrl.org/2003/role/disclosureRef
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Reference 22: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Summary of significant accounting policies - Property and equipment (Details)	12 Months Ended
	Dec. 31, 2020
Leasehold improvements
Property and equipment
Estimated useful life (in years)	5 years
Laboratory equipment \| Minimum
Property and equipment
Estimated useful life (in years)	3 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)	3 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)	3 years
Computer equipment and software \| Maximum
Property and equipment
Estimated useful life (in years)	4 years

Summary of significant accounting policies - Leases and Capitalized Software Development Cost, Revenue recognition from contracts with customers (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) item Program	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Summary of significant accounting policies
Retained earnings	$ (147,101)	$ (103,019)
Operating lease right-of-use assets	6,452	$ 7,875
Operating lease liability	5,817
Amortization expense	$ 0
Number of preclinical research programs \| Program	2
Number of combined performance obligation for each research program \| item	1
Number of research program performance obligations \| item	2
Cumulative-effect adjustment \| ASU 2016-02
Summary of significant accounting policies
Retained earnings			$ 0
Operating lease right-of-use assets			3,300
Operating lease liability			$ 3,300

Summary of significant accounting policies - Comprehensive loss (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Summary of significant accounting policies
Foreign currency translation (loss)/gain	$ (1.4)	$ (0.9)	$ (2.4)

Summary of significant accounting policies - Recent accounting pronouncements (Details) - USD ($) $ in Thousands	Jan. 01, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Summary of significant accounting policies
Retained earnings		$ (147,101)	$ (103,019)
Operating lease right-of-use assets		6,452	7,875
Operating Lease, Liability		$ 5,817
Lease, Practical Expedients, Package [true false]	true
Lease, Practical Expedient, Land Easement [true false]	true
Lease, Practical Expedient, Use of Hindsight [true false]	true
ASU 2016-02 \| Cumulative-effect adjustment
Summary of significant accounting policies
Retained earnings				$ 0
Operating lease right-of-use assets				3,300
Operating Lease, Liability				$ 3,300
ASU 2016-13 \| Cumulative-effect adjustment
Summary of significant accounting policies
Retained earnings			$ 0

Collaboration and Licensing Agreements (Details) - Gilead Collaboration and License Agreement $ in Millions	1 Months Ended	12 Months Ended
	Jun. 30, 2018 USD ($) item	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Collaboration and Licensing Agreements
Number of preclinical research programs \| item	2
Upfront payment received	$ 10.0			$ 10.0
Payment term (in days)		60 days
Milestone payment received		$ 4.0
Upfront and milestone payments included in deferred revenues		$ 2.5
Percentage of upfront payment included in deferred revenue expected to be recognized in 2021		91.00%
Percentage of upfront payment included in deferred revenue expected to be recognized in 2022		9.00%
Revenue recognized from upfront payment		$ 2.0	$ 4.4	2.8
Revenue recognized from milestone payments		2.4
Revenue recognized from cost reimbursements		1.1
Revenue recognized from milestone payments for milestones achieved		2.2	3.2
Revenue recognized from cost reimbursements for research and development services		11.9	4.3	2.0
Contract asset relating to the sublicense payment		0.1	0.3
Contract liability relating to sublicense payment		0.1	$ 0.3
Development Milestones
Collaboration and Licensing Agreements
Total milestone amount		280.0
Commercial Milestones
Collaboration and Licensing Agreements
Total milestone amount		100.0
Pre-clinical milestone
Collaboration and Licensing Agreements
Revenue recognized from milestone payments for milestones achieved				$ 2.8
Research and development expenses
Collaboration and Licensing Agreements
Cost reimbursements for research and development services included in deferred revenues		$ 2.0

Fair Value of Financial Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
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	35,397	$ 35,132
Recurring \| Money market funds
Fair Value of Financial Assets
Cash equivalents	35,397	35,132
Recurring \| Level 1
Fair Value of Financial Assets
Total	35,397	35,132
Recurring \| Level 1 \| Money market funds
Fair Value of Financial Assets
Cash equivalents	$ 35,397	$ 35,132

Property and equipment, net (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Property and equipment
Property and equipment, gross	$ 11,316	$ 8,207
Less: Accumulated depreciation	(5,097)	(3,081)
Property and equipment, net	6,219	5,126
Depreciation expense	1,700	1,100	$ 600
Leasehold improvements
Property and equipment
Property and equipment, gross	3,322	1,919
Construction in progress
Property and equipment
Property and equipment, gross	28	286
Laboratory equipment
Property and equipment
Property and equipment, gross	5,982	4,555
Furniture and fixtures
Property and equipment
Property and equipment, gross	430	524
Computer equipment and software
Property and equipment
Property and equipment, gross	$ 1,554	$ 923

Leases (Details) - USD ($) $ in Thousands	12 Months Ended
Leases (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Leases
Cash balance maintained to secure a letter of credit associated with a real estate lease	$ 434	$ 424
Presentation of leases in condensed consolidated balance sheets:
Operating lease right-of-use assets	$ 6,452	$ 7,875
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Operating lease right-of-use assets	Operating lease right-of-use assets
Finance lease right-of-use assets	$ 1,298	$ 1,602
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Finance lease right-of-use assets	Finance lease right-of-use assets
Total lease assets	$ 7,750	$ 9,477
Current operating lease liability	$ 1,998	$ 1,814
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Current operating lease liability	Current operating lease liability
Current finance lease liability	$ 155	$ 159
Finance Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:AccruedExpensesAndOtherCurrentLiabilities	us-gaap:AccruedExpensesAndOtherCurrentLiabilities
Total current lease liabilities	$ 2,153	$ 1,973
Non-current operating lease liability	$ 3,819	$ 5,290
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Non-current operating lease liability	Non-current operating lease liability
Non-current finance lease liability	$ 258	$ 367
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	us-gaap:OtherLiabilitiesNoncurrent	us-gaap:OtherLiabilitiesNoncurrent
Total non-current lease liabilities	$ 4,077	$ 5,657
Total lease liabilities	$ 6,230	7,630
Right-of-use asset derecognized		200
Lease liability derecognized		$ 200
Minimum
Leases
Remaining lease term (in years)	1 year
Maximum
Leases
Remaining lease term (in years)	3 years

Leases - Lease costs (Details) - USD ($) $ in Thousands	12 Months Ended
Leases - Lease costs (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Leases
Net lease expenses	$ 2,299	$ 2,065
Rent expense			$ 1,100
Research and development expenses
Leases
Operating lease expenses	1,654	1,108
Finance lease amortization expenses	395	350
General and Administrative Expense
Leases
Operating lease expenses	376	712
Finance lease amortization expenses	21	14
Interest expenses
Leases
Interest on finance lease liabilities	8	9
Other income (expense)
Leases
Sublease income	$ (155)	$ (128)

Leases - Minimum lease payments (Details) $ in Thousands	Dec. 31, 2020 USD ($)
Operating leases
2021	$ 1,969
2022	1,967
2023	1,952
2024	130
Total lease payments	6,018
Less: interest	201
Present value of lease liabilities	5,817
Finance leases
2021	150
2022	133
2023	130
2024	11
Total lease payments	424
Less: interest	11
Present value of lease liabilities	413
Total
2021	2,119
2022	2,100
2023	2,082
2024	141
Total lease payments	6,442
Less: interest	212
Present value of lease liabilities	$ 6,230

Leases - Weighted average remaining lease term and weighted average discount rate (Details)	1 Months Ended	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019
Leases
Operating lease, Weighted average remaining lease term (in years)	3 years 1 month 6 days	3 years 1 month 6 days	4 years 1 month 6 days
Operating lease, Weighted average discount rate	2.30%	2.30%	2.30%
Finance lease, Weighted average remaining lease term (in years)	3 years	3 years	3 years 10 months 24 days
Finance lease, Weighted average discount rate	1.70%	1.70%	1.70%
Sublease, extended term	42 days
Sublease, remaining lease term (in years)		3 months 18 days

Accrued expenses and other current liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Accrued expenses and other current liabilities
Consulting fees	$ 527	$ 724
Salaries and bonuses	4,381	2,640
Social security contributions	211	177
Unearned grant income (current)	878	725
Loans		1,224
Invoices not yet received	1,002	2,673
Finance lease liabilities	155	159
Other accruals and liabilities	232	84
Total	$ 7,386	$ 8,406

Loans payable (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended								12 Months Ended
Loans payable (Details) - USD ($) $ in Thousands	Nov. 30, 2019	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Loans payable
Loans from FFG		$ 6,564				$ 7,305				$ 6,564	$ 7,305
Unamortized debt discount		(2,027)				(2,586)				(2,027)	(2,586)
Total Loans payable, net		4,537				4,719				4,537	4,719
Revenue		5,163	$ 4,040	$ 6,685	$ 3,696	3,618	$ 2,038	$ 4,051	$ 2,235	19,584	11,942	$ 7,629
Unearned income (current)		3,750				3,591				3,750	3,591
Unearned income (non-current)		784				72				784	72
Unamortized debt discount		2,000				2,600				2,000	2,600
Interest expense										800	900	800
Amortization of debt discount										700	800	700
Principal payment										$ 1,311	842
Estimated market rate										20.00%
Threshold for change in estimated market rate										0.10
Scheduled early repayment	$ 3,300
Adjustment
Loans payable
Deferred income reduced	$ 300
Grant
Loans payable
Revenue										$ 700	800	700
Unearned income (current)		900				700				900	700	800
Unearned income (non-current)		$ 1,100				$ 1,900				$ 1,100	$ 1,900	$ 3,000
Minimum
Loans payable
Interest rate (as a percent)		0.75%								0.75%
Maximum
Loans payable
Interest rate (as a percent)		1.00%								1.00%

Loans payable - Schedule of aggregate minimum future principal payments (Details) $ in Thousands	Dec. 31, 2020 USD ($)
Long-term Debt, Fiscal Year Maturity [Abstract]
2022	$ 3,300
2023	1,968
2024	1,296
Total	$ 6,564

Redeemable convertible preferred stock (Details) - USD ($)			1 Months Ended	3 Months Ended	12 Months Ended
	Dec. 11, 2020	Apr. 23, 2019	Feb. 28, 2019	Mar. 31, 2019	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2018
Redeemable convertible preferred stock
Average price (in dollars per sale)					$ 12.23	$ 11.09	$ 10.33
Gross Proceeds from issuance of stock	$ 75,000,000
Amount reclassified upon conversion of Preferred Stock					$ 142,048,000
Preferred shares authorized (in shares)				1,580,506
Preferred shares issued and outstanding (in shares)				1,580,506
Carrying value (in dollars per sale)				$ 0.158
Common stock issuable upon conversion (in shares)				18,401,893
Number of common stock issued upon conversion of each share of Preferred Stock						1,000
IPO
Redeemable convertible preferred stock
Outstanding shares of Preferred Stock converted (in shares)		1,580,506
Amount reclassified upon conversion of Preferred Stock		$ 142,000,000
Common Stock \| IPO
Redeemable convertible preferred stock
Average price (in dollars per sale)		$ 14.00
Issuance costs		$ 9,400,000
Stock issued upon conversion of Preferred Stock (in shares)		14,582,161
Series A Preferred Stock
Redeemable convertible preferred stock
Preferred shares authorized (in shares)				137,814
Preferred shares issued and outstanding (in shares)				137,814
Carrying value (in dollars per sale)				$ 0.014
Common stock issuable upon conversion (in shares)				1,604,574
Series B Preferred Stock
Redeemable convertible preferred stock
Preferred shares authorized (in shares)				492,192
Preferred shares issued and outstanding (in shares)				492,192
Carrying value (in dollars per sale)				$ 0.049
Common stock issuable upon conversion (in shares)				5,730,612
Series C Preferred Stock
Redeemable convertible preferred stock
Preferred shares authorized (in shares)				693,500
Preferred shares issued and outstanding (in shares)				693,500
Carrying value (in dollars per sale)				$ 0.069
Common stock issuable upon conversion (in shares)				8,074,447
Series D Preferred Stock
Redeemable convertible preferred stock
Preferred Stock issued (in shares)			257,000
Average price (in dollars per sale)			$ 145.65
Gross Proceeds from issuance of stock			$ 37,400,000
Issuance costs			$ 200,000
Preferred shares authorized (in shares)				257,000
Preferred shares issued and outstanding (in shares)				257,000
Carrying value (in dollars per sale)				$ 0.026
Common stock issuable upon conversion (in shares)				2,992,260
Class A common stock
Redeemable convertible preferred stock
Number of common stock issued upon conversion of each share of Preferred Stock						11.643
Class A common stock \| IPO
Redeemable convertible preferred stock
Stock issued upon conversion of Preferred Stock (in shares)		3,819,732
Class A common stock \| Common Stock
Redeemable convertible preferred stock
Stock issued upon conversion of Preferred Stock (in shares)					3,819,732
Amount reclassified upon conversion of Preferred Stock					$ 0

Common stock, Class A common stock and convertible preferred stock (Details) $ / shares in Units, $ in Thousands			12 Months Ended
	Dec. 11, 2020 USD ($) $ / shares shares	Apr. 23, 2019 USD ($) $ / shares shares	Dec. 31, 2020 USD ($) Vote $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2018 $ / shares
Preferred Stock, Shares Authorized			10,000,000	10,000,000
Share Price \| $ / shares			$ 11.09	$ 12.23	$ 10.33
Net proceeds from public offering \| $	$ 75,000
Number of votes \| Vote			1
Common stock
Common Stock, Shares Authorized			100,000,000	100,000,000
Common stock, issued (in shares)			25,948,712	21,746,392
Common stock, outstanding (in shares)			25,948,712	21,746,392
Issuance of common stock	3,910,000
Share Price \| $ / shares	$ 11.75		$ 11.75
Offering costs \| $			$ 3,368
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
Common stock, issued (in shares)			2,978
Common stock, outstanding (in shares)			2,978
Preferred Stock, Shares Authorized			2,978	0
Preferred Stock, Shares Issued	2,978		2,978	0
Preferred Stock, Shares Outstanding			2,978	0
Share Price \| $ / shares	$ 11,750.00		$ 11,750
Offering costs \| $			$ 2,565
Number of common stock issued upon conversion of each share			1,000
Threshold Percentage For Conversion			9.99%
Preferred Stock, Liquidation Preference Per Share \| $ / shares			$ 0.001
Common Stock \| Common stock
Issuance of common stock			3,910,000	6,000,000
Stock issued upon conversion of Preferred Stock (in shares)				14,582,161
Common Stock \| Class A common stock
Stock issued upon conversion of Preferred Stock (in shares)				3,819,732
IPO \| Common stock
Share Price \| $ / shares				$ 14.00
Offering costs \| $				$ 9,386
Stock issued upon conversion of Preferred Stock (in shares)		14,582,161
IPO \| Class A common stock
Stock issued upon conversion of Preferred Stock (in shares)		3,819,732
IPO \| Common Stock
Issuance of common stock		6,000,000
Share Price \| $ / shares		$ 14.00
Net proceeds from IPO \| $		$ 74,600
Offering costs \| $		$ 9,400
Stock issued upon conversion of Preferred Stock (in shares)		14,582,161

Stock-based compensation - 2018 Stock Option and Grant Plan (Details)	12 Months Ended
	Dec. 31, 2020 installment € / shares shares	Dec. 31, 2018 shares	Dec. 31, 2019 shares
Stock-based compensation
Number of shares granted to US employee	890,904
Options outstanding	3,555,945		2,999,284
2018 Stock Option and Grant Plan
Stock-based compensation
Options outstanding	1,097,809
Vesting period	4 years
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
2016 Stock Option Plan
Stock-based compensation
Percentage of share price with fair market value	100.00%
2016 Stock Option Plan \| Exercise price 0.09 euros
Stock-based compensation
Exercise price for options granted as a replacement \| € / shares	€ 0.09
Number of shares granted to US employee	23,286
2016 Stock Option Plan \| Exercise price $2.93
Stock-based compensation
Number of shares granted to US employee		2.93

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	3,630,686
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)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Assumptions used in the Black-Scholes option-pricing model
Risk-free interest rate	0.44	2.21	2.78
Expected term (in years)	6 years 1 month 6 days	6 years 1 month 6 days	5 years 1 month 6 days
Expected volatility	80.20%	74.20%	72.10%

Stock-based compensation - Stock option activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Number of Shares
Beginning balance	2,999,284
Granted	890,904
Exercised	(255,011)
Forfeited	(79,232)
Ending balance	3,555,945	2,999,284
Option exercisable	1,459,479
Option unvested	2,096,466
Weighted Averaged Exercise Price
Beginning balance	$ 7.63
Granted	8.95
Exercised	0.25
Forfeited	9.63
Ending balance	8.45	$ 7.63
Option exercisable	6.01
Option unvested	$ 10.13
Weighted Average Remaining Contractual Term
Weighted Average Remaining Contractual Term (in years)	7 years 10 months 24 days	8 years 1 month 6 days
Weighted Average Remaining Contractual Term, option exercisable	7 years
Weighted Average Remaining Contractual Term, option unvested	8 years 7 months 6 days
Aggregate Intrinsic Value, beginning balance	$ 15,840
Aggregate Intrinsic Value, ending balance	12,839	$ 15,840
Aggregate Intrinsic Value, option exercisable	8,668
Aggregate Intrinsic Value, option unvested	$ 4,171
Average price (in dollars per sale)	$ 11.09	$ 12.23	$ 10.33
Aggregate Intrinsic Value, options exercised	$ 2,900	$ 1,400	$ 1,000
Weighted average grant-date fair value per share of stock options granted	$ 8.95	$ 7.92	$ 2.55
Total fair value of stock options vested	$ 5,600	$ 900
Cash received from option exercise under share-based payment arrangements	$ 63	$ 16	$ 9

Stock-based compensation - Restricted Stock Units (Details) - Restricted stock units	12 Months Ended
	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Stock-based compensation
Number of equal installments of vesting \| $	4
Total fair value of restricted stock vested \| $		$ 0	$ 0
Number of Shares
Granted \| shares	44,760
Vested \| shares	(1,060)
Ending balance \| shares	43,700
Weighted Average Grant Date Fair Value
Granted \| $ / shares	$ 11.87
Vested \| $ / shares	11.89
Ending balance \| $ / shares	$ 11.87

Stock-based compensation - Common Stock Awards (Details) - Common Stock Awards $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($) $ / shares shares
Stock-based compensation
Share-based awards granted \| shares	36,249
Aggregate fair value of share-based awards granted \| $	$ 0.3
Grant date fair value per share \| $ / shares	$ 9.56

Stock-based compensation - Stock-based compensation (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Stock-based compensation
Stock-based compensation expense	$ 8,657	$ 5,565	$ 867
Number of outstanding options modified			2,000
Exercise price of the stock options			$ 34.12	$ 1.17
Unrecognized compensation cost related to the unvested stock-based awards	$ 6,500	$ 9,300
Weighted average periods over which expense is expected to be recognized	1 year 7 months 6 days	1 year 9 months 18 days
Research and development expenses
Stock-based compensation
Stock-based compensation expense	$ 3,084	$ 1,981	$ 399
General and Administrative Expense
Stock-based compensation
Stock-based compensation expense	$ 5,573	$ 3,584	$ 468

Income taxes (Details) - USD ($) $ in Thousands	12 Months Ended
Income taxes (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income taxes
Income tax benefits for the net operating losses incurred	$ 0	$ 0	$ 0

Income taxes - Losses before income taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income taxes
United States	$ (11,603)	$ (7,886)	$ (604)
Foreign (Austria)	(32,479)	(35,151)	(15,609)
Net loss before tax	$ (44,082)	$ (43,037)	$ (16,213)
Company's worldwide effective tax rate	0.00%	0.00%	(0.10%)

- Definition

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

+ References

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+ Details

Income taxes - Effective income tax reconciliation (Details)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Loss Carryforwards [Line Items]
U.S. federal statutory income tax rate	(21.00%)	(21.00%)	(21.00%)	(35.00%)
Foreign tax rate differential	(4.00%)	(4.00%)	(4.00%)
Not taxable government grants	(4.70%)	(5.40%)	(7.50%)
Stock-based compensation	(1.00%)	(0.30%)	(4.60%)
Other	0.50%	(0.30%)	(0.50%)
Change in deferred tax asset valuation allowance	30.20%	31.00%	37.50%
Effective income tax rate	0.00%	0.00%	(0.10%)
Austria
Operating Loss Carryforwards [Line Items]
U.S. federal statutory income tax rate	(25.00%)

Income taxes - Components of the net deferred tax assets or liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Deferred tax assets:
Net operating loss carryforwards	$ 43,563	$ 29,180
Credit carryforwards	64	180
Accrued expenses and other	(36)	669
Stock-based compensation	2,725	2,717
Operating lease liabilities	1,513	1,740
Finance lease liabilities	103	132
Total deferred tax assets	47,932	34,618
Valuation allowance	(46,064)	(32,583)	$ (19,156)	$ (13,789)
Total deferred tax assets	1,868	2,035
Deferred tax liabilities:
Operating lease right of use asset	(1,614)	(1,808)
Finance lease right of use asset	(254)	(227)
Total deferred tax liabilities	$ (1,868)	$ (2,035)

Income taxes - Changes in the valuation allowance for deferred tax assets and others (Details) - USD ($)	12 Months Ended
	Dec. 31, 2026	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Loss Carryforwards [Line Items]
Valuation allowance at beginning of period		$ (32,583,000)	$ (19,156,000)	$ (13,789,000)
Increases		(13,481,000)	(13,427,000)	(5,367,000)
Valuation allowance at end of period		$ (46,064,000)	$ (32,583,000)	$ (19,156,000)	$ (13,789,000)
Statutory corporate tax rate		21.00%	21.00%	21.00%	35.00%
Tax rate applied on undistributed earnings in the form of cash and cash equivalents		15.50%
Tax rate applied on other earnings		8.00%
Tax payable term (in years)		8 years
Threshold return percentage of GILIT		10.00%
Reduction percentage of inclusion for GILTI		50.00%
Percentage of inclusion for GILTI	37.50%
Unrecognized income tax benefits		$ 0
Austria
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards		$ 163,200,000	$ 112,300,000	$ 76,000,000
Statutory corporate tax rate		25.00%

Commitments and contingencies (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Commitments and contingencies
Non-cancellable obligations	$ 11.9		$ 13.9
Licensing fees from intellectual property licenses	$ 1.2	$ 1.9	$ 0.1

401(k) Savings Plan (Details) $ in Millions	12 Months Ended
401(k) Savings Plan (Details) $ in Millions	Dec. 31, 2020 USD ($)
Defined Contribution Plan Disclosure [Line Items]
Expenses recognized for the 401(k) Plan	$ 0.2
Maximum
Defined Contribution Plan Disclosure [Line Items]
Matching contribution to defined contribution savings plan	100.00%
Employer's Matching contribution to defined contribution savings plan	4.00%

Net loss per share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Numerator:
Net loss	$ (12,475)	$ (13,589)	$ (7,092)	$ (10,926)	$ (10,244)	$ (11,385)	$ (12,079)	$ (9,329)	$ (44,082)	$ (43,037)	$ (16,237)
Denominator:
Weighted-average common shares outstanding, basic and diluted									25,876,376	17,859,935	914,375
Weighted-average Series A convertible preferred shares outstanding, basic and diluted, presented as if converted into common stock									162,732
Weighted-average common shares outstanding, basic and diluted									26,039,108	17,859,935	914,375
Net loss per share, basic and diluted (in USD per share)	$ (0.46)	$ (0.53)	$ (0.28)	$ (0.43)	$ (0.40)	$ (0.45)	$ (0.63)	$ (9.27)	$ (1.69)	$ (2.41)	$ (17.76)
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	2,978,000								2,978,000

- Definition

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

+ References

+ Details

Net loss per share - Antidilutive securities (Details) - shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Anti-dilutive securities
Anti-dilutive shares	3,599,645	2,999,284	17,015,958
Series A Preferred Stock
Anti-dilutive securities
Anti-dilutive shares			1,604,574
Series B Preferred Stock
Anti-dilutive securities
Anti-dilutive shares			5,730,612
Series C Preferred Stock
Anti-dilutive securities
Anti-dilutive shares			8,074,447
Options
Anti-dilutive securities
Anti-dilutive shares	3,555,945	2,999,284	1,606,325
Restricted stock units
Anti-dilutive securities
Anti-dilutive shares	43,700

Related parties (Details) - USD ($) $ in Millions	12 Months Ended
Related parties (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Series D Preferred Stock
Related parties
Shares issued		50,670
Proceeds from shares issued		$ 7.4
Common stock
Related parties
Shares issued		1,303,750
Proceeds from shares issued		$ 18.3
University of Basel
Related parties
Royalties paid	$ 0.0	0.0	$ 0.0
University of Basel \| Research and development expenses
Related parties
Service fees paid	$ 0.3	$ 0.3	$ 0.4

Selected Quarterly Financial Information (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Selected Quarterly Financial Information (Unaudited)
Revenue	$ 5,163	$ 4,040	$ 6,685	$ 3,696	$ 3,618	$ 2,038	$ 4,051	$ 2,235	$ 19,584	$ 11,942	$ 7,629
Operating expenses	(20,357)	(20,446)	(15,911)	(16,155)	(16,843)	(15,614)	(17,680)	(12,890)
Net loss	$ (12,475)	$ (13,589)	$ (7,092)	$ (10,926)	$ (10,244)	$ (11,385)	$ (12,079)	$ (9,329)	$ (44,082)	$ (43,037)	$ (16,237)
Net loss per share - basic and diluted	$ (0.46)	$ (0.53)	$ (0.28)	$ (0.43)	$ (0.40)	$ (0.45)	$ (0.63)	$ (9.27)	$ (1.69)	$ (2.41)	$ (17.76)

- Definition

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

+ References

+ Details

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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