uniQure (QURE) 10-Q10 May 212021 Q1 Quarterly reportFinancial data

Company Profile

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
Document and Entity Information - shares	Mar. 31, 2021	May 06, 2021
Document and Entity Information
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2021
Document Transition Report	false
Entity File Number	001-36294
Entity Registrant Name	uniQure N.V.
Entity Incorporation, State or Country Code	P7
Entity Address, Address Line One	Paasheuvelweg 25
Entity Address, City or Town	1105 BP Amsterdam
Entity Address, Country	NL
City Area Code	31
Local Phone Number	20-240-6000
Title of 12(b) Security	Ordinary Shares, par value €0.05
Trading Symbol	QURE
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		46,017,621
Entity Central Index Key	0001590560
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Amendment Flag	false

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets
Cash and cash equivalents	$ 260,813	$ 244,932
Accounts receivables	5,445	6,618
Prepaid expenses	9,186	4,337
Other current assets	6,886	3,024
Total current assets	282,330	258,911
Non-current assets
Property, plant and equipment, net of accumulated depreciation of $35.9 million as of March 31, 2021 and $35.2 million as of December 31, 2020, respectively	33,862	32,328
Operating lease right-of-use assets	25,313	26,086
Intangible assets, net	2,908	3,361
Goodwill	518	542
Restricted cash	2,716	2,748
Deferred tax asset	16,206	16,419
Total non-current assets	81,523	81,484
Total assets	363,853	340,395
Current liabilities
Accounts payable	5,749	3,772
Accrued expenses and other current liabilities	20,896	18,038
Current portion of operating lease liabilities	5,457	5,524
Total current liabilities	32,102	27,334
Non-current liabilities
Long-term debt	70,467	35,617
Operating lease liabilities, net of current portion	29,487	30,403
Other non-current liabilities	3,107	3,136
Total non-current liabilities	103,061	69,156
Total liabilities	135,163	96,490
Commitments and contingencies
Shareholders' equity
Ordinary shares, 0.05 par value: 60,000,000 shares authorized as of March 31, 2021 and December 31, 2020 and 45,924,729 and 44,777,799 ordinary shares issued and outstanding as of March 31, 2021 and December 31, 2020, respectively	2,780	2,711
Additional paid-in-capital	1,049,850	1,016,018
Accumulated other comprehensive income	2,347	9,907
Accumulated deficit	(826,287)	(784,731)
Total shareholders' equity	228,690	243,905
Total liabilities and shareholders' equity	$ 363,853	$ 340,395

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) $ in Millions	Mar. 31, 2021USD ($)shares	Mar. 31, 2021€ / shares	Dec. 31, 2020USD ($)shares	Dec. 31, 2020€ / shares
CONSOLIDATED BALANCE SHEETS
Accumulated depreciation \| $	$ 35.9		$ 35.2
Ordinary shares, par value (in euros per share) \| € / shares		€ 0.05		€ 0.05
Ordinary shares, authorized	60,000,000		60,000,000
Ordinary shares, issued	45,924,729		44,777,799
Ordinary shares, outstanding	45,924,729		44,777,799

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Total revenues	$ 454	$ 104
Operating expenses:
Research and development expenses	(32,656)	(26,013)
Selling, general and administrative expenses	(12,375)	(9,072)
Total operating expenses	(45,031)	(35,085)
Other income	352	857
Other expense	(233)	(339)
Loss from operations	(44,458)	(34,463)
Interest income	40	822
Interest expense	(1,551)	(975)
Foreign currency gains, net	4,626	4,602
Other non-operating gains, net		2,015
Loss before income tax expense	(41,343)	(27,999)
Income tax expense	(213)
Net loss	(41,556)	(27,999)
Other comprehensive loss:
Foreign currency translation adjustments	(7,560)	(5,277)
Total comprehensive loss	$ (49,116)	$ (33,276)
Basic and diluted net loss per ordinary share	$ (0.91)	$ (0.63)
Weighted average shares used in computing basic and diluted net loss per ordinary share	45,468,485	44,279,456
License revenues from related party
Total revenues		$ 47
Collaboration revenues
Total revenues	$ 454
Collaboration revenues from related party
Total revenues		$ 57

CONSOLIDATED STATEMENTS OF SHAR

CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Ordinary shares	Additional paid-in capital	Accumulated other comprehensive (loss)/income	Accumulated deficit	Total
Beginning balance at Dec. 31, 2019	$ 2,651	$ 986,803	$ (6,689)	$ (659,707)	$ 323,058
Beginning balance (in shares) at Dec. 31, 2019	43,711,954
Increase (decrease) in shareholders' equity
Loss for the period				(27,999)	(27,999)
Other comprehensive loss			(5,277)		(5,277)
Exercise of share options	$ 3	929			932
Exercise of share options (in shares)	64,762
Restricted and performance share units distributed during the period	$ 29	(29)
Restricted and performance share units distributed during the period (in shares)	521,079
Share-based compensation expense		4,355			4,355
Issuance of ordinary shares relating to employee stock purchase plan		78			78
Issuance of ordinary shares relating to employee stock purchase plan (in shares)	1,801
Ending balance at Mar. 31, 2020	$ 2,683	992,136	(11,966)	(687,706)	295,147
Ending balance (in shares) at Mar. 31, 2020	44,299,596
Increase (decrease) in shareholders' equity
Accumulated deficit					(784,731)
Beginning balance at Dec. 31, 2020	$ 2,711	1,016,018	9,907	(784,731)	$ 243,905
Beginning balance (in shares) at Dec. 31, 2020	44,777,799				44,777,799
Increase (decrease) in shareholders' equity
Loss for the period				(41,556)	$ (41,556)
Other comprehensive loss			(7,560)		(7,560)
Issuance of ordinary shares	$ 52	27,647			27,699
Issuance of ordinary shares (in shares)	859,885
Exercise of share options	$ 1	391			392
Exercise of share options (in shares)	16,782
Restricted and performance share units distributed during the period	$ 16	(16)
Restricted and performance share units distributed during the period (in shares)	269,089
Share-based compensation expense		5,761			5,761
Issuance of ordinary shares relating to employee stock purchase plan		49			49
Issuance of ordinary shares relating to employee stock purchase plan (in shares)	1,174
Ending balance at Mar. 31, 2021	$ 2,780	$ 1,049,850	$ 2,347	$ (826,287)	$ 228,690
Ending balance (in shares) at Mar. 31, 2021	45,924,729				45,924,729
Increase (decrease) in shareholders' equity
Accumulated deficit					$ (826,287)

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash flows from operating activities
Net loss	$ (41,556)	$ (27,999)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	1,862	1,733
Share-based compensation expense	5,761	4,355
Change in fair value of derivative financial instruments		(2,015)
Unrealized foreign exchange gains	(5,342)	(4,824)
Deferred tax expense	213
Change in deferred revenue		270
Changes in operating assets and liabilities:
Accounts receivable, prepaid expenses, and other current assets	(8,023)	(1,282)
Accounts payable	2,510	(546)
Accrued expenses, other liabilities, and operating leases	3,302	(2,645)
Net cash used in operating activities	(41,273)	(32,953)
Cash flows from investing activities
Purchases of intangible assets		(2,213)
Purchases of property, plant and equipment	(3,876)	(677)
Net cash used in investing activities	(3,876)	(2,890)
Cash flows from financing activities
Proceeds from loan increment, net of debt issuance costs	34,603
Proceeds from issuance of ordinary shares	28,734
Share issuance costs from issuance of ordinary shares	(1,161)
Proceeds from issuance of shares related to employee stock option and purchase plans	442	1,010
Net cash generated from financing activities	62,618	1,010
Currency effect on cash, cash equivalents and restricted cash	(1,620)	(943)
Net increase / (decrease) in cash, cash equivalents and restricted cash	15,849	(35,776)
Cash, cash equivalents and restricted cash at beginning of period	247,680	380,726
Cash, cash equivalents and restricted cash at the end of period	263,529	344,950
Total cash, cash equivalents and restricted cash	263,529	344,950
Supplemental cash flow disclosures:
Cash paid for interest	$ (1,410)	$ (780)

General business information

General business information	3 Months Ended
General business information	Mar. 31, 2021
General business information
General business information	1 uniQure (the “Company”) was incorporated on January 9, 2012 as a private company with limited liability ( besloten vennootschap met beperkte aansprakelijkheid naamloze vennootschap The Company is registered in the trade register of the Chamber of Commerce ( Kamer van Koophandel The Company’s ordinary shares are listed on the Nasdaq Global Select Market and trade under the symbol “QURE”.

Summary of significant accounti

Summary of significant accounting policies	3 Months Ended
Summary of significant accounting policies	Mar. 31, 2021
Summary of significant accounting policies
Summary of significant accounting policies	2 2.1 Basis of preparation The Company prepared these unaudited consolidated financial statements in compliance with generally accepted accounting principles in the United States of America (“U.S. GAAP”) and applicable rules and regulations of the Securities and Exchange Commission (“SEC”) regarding interim financial reporting. Any reference in these notes to applicable guidance is meant to refer to authoritative U.S. GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Update (“ASU”) of the Financial Accounting Standards Board (“FASB”). The unaudited consolidated financial statements are presented in U.S. dollars, except where otherwise indicated. Transactions denominated in currencies other than U.S. dollars are presented in the transaction currency with the U.S. dollar amount included in parenthesis, converted at the foreign exchange rate as of the transaction date. 2.2 Unaudited interim financial information The interim financial statements and related disclosures are unaudited, have been prepared on the same basis as the annual financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for a fair statement of the financial position, results of operations and changes in financial position for the period presented. Certain information and footnote disclosures normally included in annual financial statements prepared in accordance with U.S. GAAP have been omitted. The results of operations for the three months ended March 31, 2021, are not necessarily indicative of the results to be expected for the full year ending December 31, 2021 or for any other future year or interim period. The accompanying financial statements should be read in conjunction with the audited financial statements and the related notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020, filed with the SEC on March 1, 2021 2.3 Use of estimates The preparation of the financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements and reported amounts of revenues and expenses during the reporting periods. Actual results could differ from those estimates. 2.4 Accounting policies The principal accounting policies applied in the preparation of these unaudited consolidated financial statements are described in the Company’s audited financial statements as of and for the year ended December 31, 2020, and the notes thereto, which are included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020, filed with the SEC on March 1, 2021 2.5 Recent accounting pronouncements There have been no new accounting pronouncements or changes to accounting pronouncements during the three months ended March 31, 2021, as compared to the recent accounting pronouncements described in Note 2.3.22 of the Company’s Annual Report on Form 10-K for the year ended December 31, 2020

Collaboration arrangements and

Collaboration arrangements and concentration of credit risk	3 Months Ended
Collaboration arrangements and concentration of credit risk	Mar. 31, 2021
Collaboration arrangements and concentration of credit risk
Collaboration arrangements and concentration of credit risk	3 Collaboration arrangements and concentration of credit risk CSL Behring collaboration On June 24, 2020, uniQure biopharma B.V., a wholly-owned subsidiary of uniQure N.V., entered into a commercialization and license agreement (the “CSL Behring Agreement”) with CSL Behring LLC, (“CSL Behring”), pursuant to which CSL Behring will receive exclusive global rights to etranacogene dezaparvovec, the Company’s investigational gene therapy for patients with hemophilia B, (the “Product”). Under the terms of the CSL Behring Agreement, the Company is entitled to receive a $450.0 million upfront cash payment upon the closing of the transaction contemplated by the CSL Behring Agreement and will be eligible to receive up to $1.6 billion in additional payments based on regulatory and commercial milestones. The CSL Behring Agreement also provides that the Company will be eligible to receive tiered double-digit royalties in a range of up to a low-twenties percent of net sales of the Product based on sales thresholds. Pursuant to the CSL Behring Agreement, the Company will be responsible for the completion of the HOPE-B clinical trial, manufacturing process validation, and the manufacturing supply of the Product until such time that these capabilities may be transferred to CSL Behring or its designated contract manufacturing organization. Concurrently with the execution of the CSL Behring Agreement, the Company and CSL Behring entered into a development and commercial supply agreement, pursuant to which, among other things, the Company will supply the Product to CSL Behring at an agreed-upon price. Clinical development and regulatory activities performed by the Company pursuant to the CSL Behring Agreement will be reimbursed by CSL Behring. CSL Behring will be responsible for global regulatory submissions and commercialization requirements for the Product. The effectiveness of the transaction contemplated by the CSL Behring Agreement was contingent on completion of review under antitrust laws in the United States, Australia, and the United Kingdom. As of March 31, 2021, such regulatory approvals had not been received in the United States. On May 5, 2021 the waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976 (the “HSR Act”) expired, and as such the CSL Behring Agreement became fully effective on May 6, 2021. As of March 31, 2021, the Company concluded it has no enforceable right to the upfront payment, the regulatory and sale milestone payments, or the royalties (together “CSL Behring License Revenue”) that the Company will receive in accordance with the CSL Behring Agreement, as all payments were contingent upon the successful completion of reviews, or the expiration of the waiting period, under the HSR Act, which had not occurred as of March 31, 2021. Therefore, the Company determined to not recognize any revenue in relation to the CSL Behring License Revenue, in accordance with ASC 606 during the three-month period ended March 31, 2021. In accordance with its existing license and other agreements, the Company is contractually required to pay in total a low to high single digit percentage of any upfront payment to its licensors and financial advisor (“License Fees”) following the closing of the transaction. The Company did not record any License Fees for the three-month period ended March 31, 2021, as the Company had not recognized the upfront payment as of this date. The Company incurred $5.0 million of expenses related to the obligations related to the CSL Behring Agreement that had not been satisfied as of March 31, 2021. The Company capitalized these expenses as contract fulfillment costs (presented within Other current assets). As of March 31, 2021, the Company also recognized a $5.0 million receivable (presented within Accounts receivable) from CSL Behring for expenses for which the Company has a right of reimbursement. A contract liability was also recognized for the entire amount of expenses for which the Company has a right to reimbursement (presented within Accrued expenses and other current liabilities). In accordance with ASC 606 it cannot recognize any CSL Behring License Revenue as of this date. Bristol-Myers Squibb collaboration In May 2015, the Company and Bristol-Myers Squibb (“BMS”) entered into a collaboration and license agreement and various related agreements with BMS (“BMS CLA”). The initial four-year research term under the collaboration terminated on May 21, 2019. On December 1, 2020, the Company and BMS amended the BMS CLA (“amended BMS CLA”). Under the amended BMS CLA, BMS is limited to four Collaboration Targets. BMS may until November 30, 2021 replace up to two of these four Collaboration Targets with up to two new targets in the field of cardiovascular disease. The Company continues to be eligible to receive research, development, and regulatory milestone payments of up to $217.0 million for each Collaboration Target, if defined milestones are achieved. For as long as any of the four Collaboration Targets are being advanced, BMS may place a purchase order to be supplied with research, clinical and commercial supplies. Subject to the terms of the amended BMS CLA, BMS has the right to terminate the research, clinical and commercial supply relationships, and has certain remedies for failures of supply, up to and including technology transfer for any such failure that otherwise cannot be reasonably resolved. Both BMS and the Company may agree to a technology transfer of manufacturing capabilities pursuant to the terms of the amended BMS CLA. The amended BMS CLA does not extend the initial four-year research term. BMS may place purchase orders to provide limited services primarily related to analytical and development efforts in respect of the four Collaboration Targets. BMS may request such services for a period not to exceed the earlier of (i) the completion of all activities under a Research Plan and (ii) either (A) three years after the last replacement target has been designated by BMS during the one-year replacement period ending on November 30, 2021, or (B) November 30, 2023 if no replacement targets are designated. BMS continues to reimburse the Company for these services. The Company evaluated the impact of the amended BMS CLA in relation to its performance obligation to provide access to BMS to its technology and know-how in the field of gene therapy and to participate in joint steering committee and other governing bodies (“License Revenue”). The Company determined that its remaining performance obligation under the amended BMS CLA was immaterial and recognized the remaining balance of unrecognized License Revenue as of November 30, 2020. The Company includes variable consideration related to any research, development, and regulatory milestone payments, in the transaction price once it is considered probable that including these payments in the transaction price would not result in the reversal of cumulative revenue recognized. Due to the significant uncertainty surrounding the development of gene-therapy product candidates and the dependence on BMS’s performance and decisions, the Company does not generally consider this probable and did not record any License Revenue during the three months ended March 31, 2021.

Fair value measurement

Fair value measurement	3 Months Ended
Fair value measurement	Mar. 31, 2021
Fair value measurement
Fair value measurement	4 The Company measures certain financial assets and liabilities at fair value, either upon initial recognition or for subsequent accounting or reporting. U.S. GAAP requires disclosure of methodologies used in determining the reported fair values, and establishes a hierarchy of inputs used when available. The three levels of the fair value hierarchy are described below: ● Level 1 – Valuations based on unadjusted quoted prices in active markets for identical assets or liabilities that the Company can access at the measurement date. ● Level 2 – Valuations based on quoted prices for similar assets or liabilities in markets that are not active or models for which the inputs are observable, either directly or indirectly. ● Level 3 – Valuations that require inputs that reflect the Company’s own assumptions that are both significant to the fair value measurement and are unobservable. To the extent that valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized as Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. The carrying amount of cash and cash equivalents, accounts receivable, prepaid expenses, other assets, accounts payable, accrued expenses and other current liabilities reflected in the Consolidated balance sheets approximate their fair values due to their short-term maturities. The following table sets forth the Company’s assets and liabilities that are required to be measured at fair value on a recurring basis as of March 31, 2021, and December 31, 2020: Quoted prices Significant Significant Total Classification in Consolidated (in thousands) At December 31, 2020 Assets: Cash, cash equivalents and restricted cash $ 247,680 $ — $ — $ 247,680 Cash and cash equivalents; restricted cash Total assets $ 247,680 $ — $ — $ 247,680 Liabilities: Derivative financial instruments — — 2,645 2,645 Other non-current liabilities Total liabilities $ — $ — $ 2,645 $ 2,645 At March 31, 2021 Assets: Cash, cash equivalents and restricted cash $ 263,529 $ — $ — $ 263,529 Cash and cash equivalents; restricted cash Total assets $ 263,529 $ — $ — $ 263,529 Liabilities: Derivative financial instruments $ — $ — $ 2,645 $ 2,645 Other non-current liabilities Total liabilities $ — $ — $ 2,645 $ 2,645 Changes in Level 3 items during the three months ended March 31, 2021, are as follows: Derivative financial instruments (in thousands) Balance at December 31, 2020 $ 2,645 Net (gains) / losses recognized in profit or loss — Balance at March 31, 2021 $ 2,645 Derivative financial instruments The Company issued derivative financial instruments related to its collaboration with BMS. In 2015, the Company granted BMS two warrants that were subsequently terminated in connection with the amendment to the BMS CLA on December 1, 2020. On December 1, 2020, the Company and BMS agreed that upon the consummation of a change of control transaction of uniQure that occurs prior to December 1, 2026 or BMS’ delivery of a target cessation notice for all four Collaboration Targets, the Company (or its third party acquirer) shall pay to BMS a one-time, non-refundable, non-creditable cash payment of $70.0 million, provided that (x) if $70.0 million is greater than five percent (5.0%) of the net proceeds (as contractually defined) from such change of control transaction, the payment shall be an amount equal to five percent of such net proceeds, and (y) if $70.0 million is less than one percent of such net proceeds, the change of control payment shall be an amount equal to one percent of such net proceeds (“CoC-payment”). The Company has not consummated any change of control transaction as of March 31, 2021 that would obligate it to make a CoC-payment. The Company determined that the CoC-payment should be recorded as a derivative financial liability as of December 1, 2020 and that subsequent changes in the fair market value of this derivative financial liability should be recorded in profit and loss. The fair market value of the derivative financial liability is materially impacted by probability that market participants assign to the likelihood of the occurrence of a change of control transaction that would give rise to a CoC-payment. This probability represents an unobservable input. The Company determined the fair market value of the derivative financial liability by using a present value model based on expected cash flow. The expected cash flows are materially impacted by the probability that market participants assign to the likelihood of the occurrence of a change of control transaction within the biotechnology industry. The Company estimated this unobservable input using the best information available as of March 31, 2021 and December 31, 2020. The Company obtained reasonably available market information that it believed market participants would use in determining the likelihood of the occurrence of a change-of control transaction within the biotechnology industry. Selecting and evaluating market information involves considerable judgement and uncertainty. Based on all such information and its judgment the Company estimated that the fair market value of the derivative financial liability (presented within “Other non-current liabilities”) as of March 31, 2021 and December 31, 2020 was $2.6 million.

Accrued expenses and other curr

Accrued expenses and other current liabilities	3 Months Ended
Accrued expenses and other current liabilities	Mar. 31, 2021
Accrued expenses and other current liabilities
Accrued expenses and other current liabilities	5 Accrued expenses and other current liabilities Accrued expenses and other current liabilities include the following items: March 31, December 31, 2021 2020 (in thousands) Accruals for services provided by vendors-not yet billed $ 11,180 $ 8,269 Personnel related accruals and liabilities 4,716 7,687 Contract liability (see Note 3. "Collaboration arrangements") 5,000 2,082 Total $ 20,896 $ 18,038

Long-term debt

Long-term debt	3 Months Ended
Long-term debt	Mar. 31, 2021
Long-term debt
Long-term debt	6 Long-term debt On June 14, 2013, the Company entered into a venture debt loan facility with Hercules Capital, Inc. (formerly known as Hercules Technology Growth Capital, Inc.) (“Hercules”), which was amended and restated on June 26, 2014, and again on May 6, 2016 (“2016 Amended Facility”). On December 6, 2018, the Company signed an amendment that both refinanced the then-existing $20.0 million 2016 Amended Facility and allowed the Company to draw down an additional $15.0 million (“2018 Amended Facility”). The 2018 Amended Facility extended the loan’s maturity date from May 1, 2020 until June 1, 2023. The interest-only period was initially extended from November 2018 to January 1, 2021 and was further extended to January 1, 2022 as a result of raising more than $90.0 million in equity financing in September 2019. The interest only period was again further extended to June 1, 2023 as a result of the January 2021 amendment (see below). The interest rate is adjustable and is the greater of (i) 8.85% and (ii) 8.85% plus the prime rate less 5.50% per annum. Under the 2018 Amended Facility, the Company owes a back-end fee of 4.95% of the outstanding debt. In addition, in May 2020 the Company paid a back-end fee of $1.0 million in relation to the 2016 Amended Facility. On January 29, 2021, the Company and Hercules amended the 2018 Amended Facility (“2021 Amended Facility”). Pursuant to the 2021 Amended Facility, Hercules agreed to an additional Facility of $100.0 million (“Tranche B”), increasing the aggregate principal amount of the term loan facilities from $35.0 million to up to $135.0 million. On January 29, 2021, the Company drew down $35.0 million of the Tranche B. The Company may draw down the remaining $65.0 million under the Tranche B in a series of one or more advances of not less than $20.0 million each until December 15, 2021. Advances under Tranche B bear interest at a rate equal to the greater of (i) 8.25% or (ii) 8.25% plus the prime rate, less 3.25% per annum. The principal balance and all accrued but unpaid interest on advances under Tranche B is due on June 1, 2023, which date may be extended by the Company by up to two twelve-month periods. Advances under Tranche B may not be prepaid prior to July 29, 2021, following which the Company may prepay all such advances without charge. The amortized cost (including interest due presented as part of accrued expenses and other current liabilities) of the 2018 Amended Facility and 2021 Amended Facility was $71.0 million as of March 31, 2021, compared to $35.9 million amortized cost for the 2018 Amended Facility as of December 31, 2020, and is recorded net of discount and debt issuance costs. The foreign currency loss on the facilities in the three months ended March 31, 2021, was $3.2 million compared to a foreign currency loss of $0.7 million during the same period in 2020 for the 2018 Amended Facility. Interest expense associated with the 2018 Amended Facility and 2021 Amended Facility during the three months ended March 31, 2021 was $1.5 million, compared to $0.9 million during the same periods in 2020 for the 2018 Amended Facility. As a covenant in the 2018 Amended Facility and 2021 Amended Facility, the Company has periodic reporting requirements and is required to keep a minimum cash balance deposited in bank accounts in the United States, equivalent to the lesser of (i) 65% of the outstanding balance of principal due or (ii) 100% of worldwide cash and cash equivalents. This restriction on cash and cash equivalents only relates to the location of the cash and cash equivalents, and such cash and cash equivalents can be used at the discretion of the Company. In combination with other covenants, the 2018 Amended Facility and 2021 Amended Facility restricts the Company’s ability to, among other things, incur future indebtedness and obtain additional debt financing, to make investments in securities or in other companies, to transfer assets, to perform certain corporate changes, to make loans to employees, officers, and directors, and to make dividend payments and other distributions to its shareholders. The Company secured the facilities by directly or indirectly pledging its total assets of $363.9 million with the exception of $97.6 million of cash and cash equivalents and other current assets held by uniQure N.V. The 2018 Amended Facility and 2021 Amended Facility contain provisions that include the occurrence of a material adverse effect, as defined therein, which would entitle Hercules to declare all principal, interest and other amounts owed by the Company immediately due and payable. As of March 31, 2021, the Company was in material compliance with all covenants and provisions.

Shareholders' equity

Shareholders' equity	3 Months Ended
Shareholders' equity	Mar. 31, 2021
Shareholders' equity
Shareholders' equity	7 On March 1, 2021, the Company entered into a Sales Agreement with SVB Leerink LLC (“SVB Leerink”) with respect to an at-the-market (“ATM”) offering program, under which the Company may, from time to time in its sole discretion, offer and sell through SVB Leerink, acting as agent, its ordinary shares, up to an aggregate offering price of $200.0 million. The Company will pay SVB Leerink a commission equal to 3% of the gross proceeds of the sales price of all ordinary shares sold through it as sales agent under the Sales Agreement. Through March 31, 2021 the Company issued 859,885 ordinary shares at a weighted average price of $33.42 per share, with net proceeds of $27.6 million, after deducting underwriting discounts and net of offering expenses. The Company defers direct, incremental costs associated to this offering, except for the commission costs to SVB Leerink, which are a reduction to additional paid-in capital, and will deduct these costs from additional paid-in capital in the consolidated balance sheets proportionately to the amount of proceeds raised. As of March 31, 2021, $1.0 million of direct, incremental costs were deducted from additional paid-in capital.

Share-based compensation

Share-based compensation	3 Months Ended
Share-based compensation	Mar. 31, 2021
Share-based compensation
Share-based compensation	8 The Company’s share-based compensation plans include the 2014 Amended and Restated Share Option Plan (the “2014 Plan”) and inducement grants under Rule 5653(c)(4) of the Nasdaq Global Select Market with terms similar to the 2014 Plan (together the “2014 Plans”). At the annual general meeting of shareholders in June 2018, the Company’s shareholders approved amendments of the 2014 Plan, increasing the shares authorized for issuance by 3,000,000 to a total of 8,601,471 . a) 2014 Plans Share-based compensation expense recognized by classification included in the Consolidated statements of operations and comprehensive loss in relation to the 2014 Plans for the periods indicated below was as follows: Three months ended March 31, 2021 2020 (in thousands) Research and development $ 2,674 $ 2,382 Selling, general and administrative 3,080 1,958 Total $ 5,754 $ 4,340 Share-based compensation expense recognized by award type was as follows: Three months ended March 31, 2021 2020 (in thousands) Award type Share options $ 2,840 $ 2,208 Restricted share units 2,560 1,444 Performance share units 354 688 Total $ 5,754 $ 4,340 As of March 31, 2021, the unrecognized share-based compensation expense related to unvested awards under the 2014 Plans were: Unrecognized Weighted average share-based remaining compensation period for expense recognition (in thousands) (in years) Award type Share options $ 35,517 3.09 Restricted share units 26,227 2.40 Performance share units 1,241 0.83 Total $ 62,985 2.76 The Company satisfies the exercise of share options and vesting of Restricted Share Units (“RSUs”) and Performance Share Units (“PSUs”) through newly issued ordinary shares. Share options Share options are priced on the date of grant and, except for certain grants made to non-executive directors, vest over a period of four years. The first 25% vests after one year from the initial grant date and the remainder vests in equal quarterly installments over years two, three and four. Certain grants to non-executive directors vest in full after one year. Any options that vest must be exercised by the tenth anniversary of the initial grant date. The following tables summarize option activity under the Company’s 2014 Plans for the three months ended March 31, 2021: Options Number of Weighted average ordinary shares exercise price Outstanding at December 31, 2020 2,659,279 $ 28.13 Granted 734,683 $ 36.95 Forfeited (40,440) $ 43.85 Expired (5,094) $ 37.85 Exercised (16,782) $ 23.34 Outstanding at March 31, 2021 3,331,646 $ 29.90 Thereof, fully vested and exercisable at March 31, 2021 1,718,923 $ 20.19 Thereof, outstanding and expected to vest after March 31, 2021 1,612,723 $ 40.24 Total weighted average grant date fair value of options issued during the period (in $ millions) $ 15.8 Proceeds from option sales during the period (in $ millions) $ 0.4 The fair value of each option issued is estimated at the respective grant date using the Hull & White option pricing model with the following weighted-average assumptions: Three months ended March 31, Assumptions 2021 2020 Expected volatility 75% 70% Expected terms 10 years 10 years Risk free interest rate 1.21% - 1.71% 1.44% Expected dividend yield 0% 0% Restricted share units (“RSUs”) The following table summarizes the RSUs activity for the three months ended March 31, 2021: RSU Weighted average Number of grant-date fair ordinary shares value Non-vested at December 31, 2020 467,344 $ 43.56 Granted 404,967 $ 36.96 Vested (136,721) $ 38.63 Forfeited (15,938) $ 43.46 Non-vested at March 31, 2021 719,652 $ 40.79 Total weighted average grant date fair value of RSUs granted during the period (in $ millions) $ 15.0 RSUs vest over one Performance share units (“PSUs”) The following table summarizes the PSUs activity for the three months ended March 31, 2021: PSU Weighted average Number of grant-date fair ordinary shares value Non-vested at December 31, 2020 212,614 $ 42.32 Vested (132,368) $ 33.09 Forfeited (2,916) $ 57.56 Non-vested at March 31, 2021 77,330 $ 57.56 The PSUs will vest on the third anniversary of the grant, subject to the grantee’s continued employment. b) Employee Share Purchase Plan (“ESPP”) In June 2018, the Company’s shareholders adopted and approved an ESPP allowing the Company to issue up to 150,000 ordinary shares. The ESPP is intended to qualify under Section 423 of the Internal Revenue Code of 1986. Under the ESPP, employees are eligible to purchase ordinary shares through payroll deductions, subject to any plan limitations. The purchase price of the ordinary shares on each purchase date is equal to 85% of the lower of the closing market price on the offering date and the closing market price on the purchase date of each three-month offering period. During the three months ended March 31, 2021, 1,174 ordinary shares were issued under the ESPP compared to 1,801 during the same period in 2020. As of March 31, 2021, a total of 130,852 ordinary shares remain available for issuance under the ESPP plan compared to a total of 136,406 as of March 31, 2020.

Income taxes

Income taxes	3 Months Ended
Income taxes	Mar. 31, 2021
Income taxes
Income taxes	9 Income taxes The Company released its valuation allowance against the Company’s deferred tax assets in the United States as of December 31, 2020. The Company recorded $0.2 million deferred tax expense in relation to its operations in the United States during the three month period ended March 31, 2021. The Company recorded a nil net deferred tax expense in the prior year as it had recorded a valuation allowance against its net deferred tax assets in the United States as of March 31, 2020. The effective income tax rate of 0.5% during the three months ended March 31, 2021 is substantially lower than the enacted rated of 25% in the Netherlands as the Company recorded a valuation allowance against its net deferred tax assets in the Netherlands. Refer to Note 3 “Collaboration arrangements and concentration of credit risk” for discussion on the effectiveness of the CSL Behring Agreement. The effective income tax rate during the three months ended March 31, 2020 was 0% as the Company had recorded a valuation allowance against all its net deferred tax assets. The closing of the transaction contemplated by the CSL Behring agreement on May 6, 2021 is expected to materially impact the Company’s operating result as well as the taxable income for the year ended December 31, 2021 as well as in future periods. The Company expects to utilize a material portion of its net operating loss carryforwards in the Netherlands during 2021 as a result of closing the transaction. As of March 31, 2021 the Company expects to continue incurring tax losses in the years thereafter and expects to record a valuation allowance against all its Dutch net deferred tax assets as of December 31, 2021. The Company determined the impact which recognition of CSL Behring License Revenue is estimated to have, with regards to the expected effective tax rate of 0% that was applied with respect to the Company’s Dutch operations as of March 31, 2021, is immaterial.

Basic and diluted earnings per

Basic and diluted earnings per share	3 Months Ended
Basic and diluted earnings per share	Mar. 31, 2021
Basic and diluted earnings per share
Basic and diluted earnings per share	10 Diluted earnings per share are calculated by adjusting the weighted average number of ordinary shares outstanding, assuming conversion of all potentially dilutive ordinary shares. As the Company has incurred a loss, all potentially dilutive ordinary shares would have an antidilutive effect, if converted, and thus have been excluded from the computation of loss per share. The shares are presented without giving effect to the application of the treasury method or exercise prices that would be above the share price as of March 31, 2021 and March 31, 2020, respectively. In addition, the BMS warrants were not exercisable as of March 31, 2020 since this would have required the prior designation of Collaboration Targets by BMS. This would generally result in a lower number of potentially dilutive ordinary shares as some stock option grants as well as the BMS warrants would have been excluded. The potentially dilutive ordinary shares are summarized below: March 31, 2021 2020 (ordinary shares) BMS warrants (derecognized as of December 1, 2020 - see Note 4, "Fair value measurement") — 10,262,500 Stock options under 2014 Plans 3,331,646 3,003,430 Non-vested RSUs and earned PSUs 796,982 635,390 Stock options under previous option plan 14,000 14,000 Employee share purchase plan 729 681 Total potential dilutive ordinary shares 4,143,357 13,916,001

Subsequent events

Subsequent events	3 Months Ended
Subsequent events	Mar. 31, 2021
Subsequent events
Subsequent events	11 Appointment of Chief Operating Officer Effective May 17, 2021, Pierre Caloz will be appointed as Chief Operating Officer and will be based out of the Amsterdam facility. Mr. Caloz will be responsible for all Manufacturing Operations, Global Chemistry, Manufacturing and Controls development and innovation, and Supply Chain and Facilities. As a result, Alex Kuta, Ph.D., will transition from Executive Vice President, Operations to Executive Vice President, Quality and Regulatory. Closing of Collaboration and Licensing transaction with CSL Behring (see also note 3) On May 5, 2021, the waiting period under the HSR Act expired, and on May 6, 2021 the CSL Behring Agreement became fully effective. Under the CSL Behring Agreement, the upfront payment of $450.0 million was paid to the Company on May 7, 2021. Additionally, the Company is eligible to receive more than $300 million in regulatory and first commercial sale milestones, up to an additional $1.3 billion in commercial milestones, and tiered double-digit royalties of up to a low-twenties percentage of net sales of the Product arising from the collaboration. The Company contractually owes a single-digit percentage of revenue from the collaboration to its licensors. The Company expects to utilize a material portion of its net operating loss carryforwards in the Netherlands during 2021 as a result of closing the transaction contemplated by the CSL Behring Agreement. The Company will be responsible for the completion of the HOPE-B clinical trial, manufacturing process validation, and the manufacturing supply of the Product until such time that these capabilities may be transferred to CSL Behring or its designated contract manufacturing organization. Clinical development and regulatory activities performed by the Company pursuant to the CSL Behring Agreement will be reimbursed by CSL Behring. CSL Behring will be responsible for global regulatory submissions and commercialization requirements for the Product.

Summary of significant accoun_2

Summary of significant accounting policies (Policies)	3 Months Ended
Summary of significant accounting policies (Policies)	Mar. 31, 2021
Summary of significant accounting policies
Basis of preparation	2.1 Basis of preparation The Company prepared these unaudited consolidated financial statements in compliance with generally accepted accounting principles in the United States of America (“U.S. GAAP”) and applicable rules and regulations of the Securities and Exchange Commission (“SEC”) regarding interim financial reporting. Any reference in these notes to applicable guidance is meant to refer to authoritative U.S. GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Update (“ASU”) of the Financial Accounting Standards Board (“FASB”). The unaudited consolidated financial statements are presented in U.S. dollars, except where otherwise indicated. Transactions denominated in currencies other than U.S. dollars are presented in the transaction currency with the U.S. dollar amount included in parenthesis, converted at the foreign exchange rate as of the transaction date.
Unaudited interim financial information	2.2 Unaudited interim financial information The interim financial statements and related disclosures are unaudited, have been prepared on the same basis as the annual financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for a fair statement of the financial position, results of operations and changes in financial position for the period presented. Certain information and footnote disclosures normally included in annual financial statements prepared in accordance with U.S. GAAP have been omitted. The results of operations for the three months ended March 31, 2021, are not necessarily indicative of the results to be expected for the full year ending December 31, 2021 or for any other future year or interim period. The accompanying financial statements should be read in conjunction with the audited financial statements and the related notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020, filed with the SEC on March 1, 2021
Use of estimates	2.3 Use of estimates The preparation of the financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements and reported amounts of revenues and expenses during the reporting periods. Actual results could differ from those estimates.
Accounting policies	2.4 Accounting policies The principal accounting policies applied in the preparation of these unaudited consolidated financial statements are described in the Company’s audited financial statements as of and for the year ended December 31, 2020, and the notes thereto, which are included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020, filed with the SEC on March 1, 2021
Recent accounting pronouncements	2.5 Recent accounting pronouncements There have been no new accounting pronouncements or changes to accounting pronouncements during the three months ended March 31, 2021, as compared to the recent accounting pronouncements described in Note 2.3.22 of the Company’s Annual Report on Form 10-K for the year ended December 31, 2020

Fair value measurement (Tables)

Fair value measurement (Tables)	3 Months Ended
Fair value measurement (Tables)	Mar. 31, 2021
Fair value measurement
Schedule of assets and liabilities measured at fair value on recurring basis	Quoted prices Significant Significant Total Classification in Consolidated (in thousands) At December 31, 2020 Assets: Cash, cash equivalents and restricted cash $ 247,680 $ — $ — $ 247,680 Cash and cash equivalents; restricted cash Total assets $ 247,680 $ — $ — $ 247,680 Liabilities: Derivative financial instruments — — 2,645 2,645 Other non-current liabilities Total liabilities $ — $ — $ 2,645 $ 2,645 At March 31, 2021 Assets: Cash, cash equivalents and restricted cash $ 263,529 $ — $ — $ 263,529 Cash and cash equivalents; restricted cash Total assets $ 263,529 $ — $ — $ 263,529 Liabilities: Derivative financial instruments $ — $ — $ 2,645 $ 2,645 Other non-current liabilities Total liabilities $ — $ — $ 2,645 $ 2,645
Schedule of changes in Level 3 items	Derivative financial instruments (in thousands) Balance at December 31, 2020 $ 2,645 Net (gains) / losses recognized in profit or loss — Balance at March 31, 2021 $ 2,645

Accrued expenses and other cu_2

Accrued expenses and other current liabilities (Tables)	3 Months Ended
Accrued expenses and other current liabilities (Tables)	Mar. 31, 2021
Accrued expenses and other current liabilities
Schedule of accrued expenses and other current liabilities	March 31, December 31, 2021 2020 (in thousands) Accruals for services provided by vendors-not yet billed $ 11,180 $ 8,269 Personnel related accruals and liabilities 4,716 7,687 Contract liability (see Note 3. "Collaboration arrangements") 5,000 2,082 Total $ 20,896 $ 18,038

Share-based compensation (Table

Share-based compensation (Tables)	3 Months Ended
Share-based compensation (Tables)	Mar. 31, 2021
Share-based compensation
Schedule of share-based compensation expense by classification included in consolidated statements of operations and comprehensive loss	Three months ended March 31, 2021 2020 (in thousands) Research and development $ 2,674 $ 2,382 Selling, general and administrative 3,080 1,958 Total $ 5,754 $ 4,340
Schedule of share-based compensation expense	Three months ended March 31, 2021 2020 (in thousands) Award type Share options $ 2,840 $ 2,208 Restricted share units 2,560 1,444 Performance share units 354 688 Total $ 5,754 $ 4,340
Schedule of unrecognized compensation cost related to unvested awards	Unrecognized Weighted average share-based remaining compensation period for expense recognition (in thousands) (in years) Award type Share options $ 35,517 3.09 Restricted share units 26,227 2.40 Performance share units 1,241 0.83 Total $ 62,985 2.76
Schedule of weighted-average assumptions for fair value of option issued	Three months ended March 31, Assumptions 2021 2020 Expected volatility 75% 70% Expected terms 10 years 10 years Risk free interest rate 1.21% - 1.71% 1.44% Expected dividend yield 0% 0%
Summary of RSUs activity	RSU Weighted average Number of grant-date fair ordinary shares value Non-vested at December 31, 2020 467,344 $ 43.56 Granted 404,967 $ 36.96 Vested (136,721) $ 38.63 Forfeited (15,938) $ 43.46 Non-vested at March 31, 2021 719,652 $ 40.79 Total weighted average grant date fair value of RSUs granted during the period (in $ millions) $ 15.0
Summary of PSUs activity	PSU Weighted average Number of grant-date fair ordinary shares value Non-vested at December 31, 2020 212,614 $ 42.32 Vested (132,368) $ 33.09 Forfeited (2,916) $ 57.56 Non-vested at March 31, 2021 77,330 $ 57.56
2014 Plan
Share-based compensation
Summary of option activity	Options Number of Weighted average ordinary shares exercise price Outstanding at December 31, 2020 2,659,279 $ 28.13 Granted 734,683 $ 36.95 Forfeited (40,440) $ 43.85 Expired (5,094) $ 37.85 Exercised (16,782) $ 23.34 Outstanding at March 31, 2021 3,331,646 $ 29.90 Thereof, fully vested and exercisable at March 31, 2021 1,718,923 $ 20.19 Thereof, outstanding and expected to vest after March 31, 2021 1,612,723 $ 40.24 Total weighted average grant date fair value of options issued during the period (in $ millions) $ 15.8 Proceeds from option sales during the period (in $ millions) $ 0.4

Basic and diluted earnings pe_2

Basic and diluted earnings per share (Tables)	3 Months Ended
Basic and diluted earnings per share (Tables)	Mar. 31, 2021
Basic and diluted earnings per share
Schedule of potential dilutive common shares	March 31, 2021 2020 (ordinary shares) BMS warrants (derecognized as of December 1, 2020 - see Note 4, "Fair value measurement") — 10,262,500 Stock options under 2014 Plans 3,331,646 3,003,430 Non-vested RSUs and earned PSUs 796,982 635,390 Stock options under previous option plan 14,000 14,000 Employee share purchase plan 729 681 Total potential dilutive ordinary shares 4,143,357 13,916,001

Collaboration arrangements an_2

Collaboration arrangements and concentration of credit risk - BMS collaboration - Narrative (Details) $ in Thousands	Dec. 01, 2020USD ($)item	Jun. 24, 2020USD ($)	Mar. 31, 2021USD ($)item	Mar. 31, 2020USD ($)
Collaboration arrangements
Number of collaboration targets \| item			4
Revenue			$ 454	$ 104
Tax rate enacted in the Netherlands			25.00%
CSL Behring collaboration
Collaboration arrangements
Upfront cash to receive upon the closing of the agreement		$ 450,000
Upfront payment recorded			$ 0
Regulatory and commercial milestone payments received		$ 1,600,000	5,000
Other Current Assets \| CSL Behring collaboration
Collaboration arrangements
Capitalized Contract Cost, Net			$ 5,000
License revenues from related party
Collaboration arrangements
Revenue				47
Collaboration revenues from related party
Collaboration arrangements
Revenue				$ 57
BMS arrangement \| Bristol Myers Squibb
Collaboration arrangements
Initial research term			4 years
Number of collaboration targets \| item	4
Collaboration Agreement, Threshold Number Of Collaboration Targets That Can Be Replaced \| item	2
Threshold Number Of New Collaboration Targets In The Field Of Cardiovascular Disease \| item	2
License revenue \| CSL Behring collaboration
Collaboration arrangements
Revenue			$ 0
License revenue \| Bristol Myers Squibb
Collaboration arrangements
Revenue			$ 0
Bristol Myers Squibb \| BMS arrangement
Collaboration arrangements
Collaboration Agreement, Threshold Research, Development And Regulatory Milestone Payments Receivable	$ 217,000

Fair value measurement - Assets

Fair value measurement - Assets and liabilities measured on a recurring basis (Details) - Recurring - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	$ 263,529	$ 247,680
Total assets	263,529	247,680
Liabilities, Fair Value Disclosure [Abstract]
Fair value of derivative liability	2,645	2,645
Total liabilities	2,645	2,645
Fair value hierarchy Level 1
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	263,529	247,680
Total assets	263,529	247,680
Level 3
Liabilities, Fair Value Disclosure [Abstract]
Fair value of derivative liability	2,645	2,645
Total liabilities	$ 2,645	$ 2,645

Fair value measurement - Change

Fair value measurement - Changes in Level 3 items (Details) - Derivative financial instruments - Level 3 $ in Thousands	Mar. 31, 2021USD ($)
Changes in Level 3 liabilities
Beginning Balance	$ 2,645
Ending Balance	$ 2,645

Fair value measurement - BMS wa

Fair value measurement - BMS warrants - Narrative (Details) $ in Millions	3 Months Ended
	Mar. 31, 2021USD ($)item	Dec. 31, 2020USD ($)
Collaboration arrangements
Number of warrant types \| item	2
Number of Collaboration Targets \| item	4
Collaboration Agreement, Cash Payable \| $	$ 70
Non-current liabilities
Collaboration arrangements
Fair value of the derivative financial liability \| $	$ 2.6	$ 2.6
Collaboration Agreement, If 70 Million Is Greater Than Five Percent Of Net Proceeds \| Derecognition Of Warrants
Collaboration arrangements
Threshold Percentage Of Net Proceeds	5
Percentage Of Net Proceeds Payable	5
Collaboration Agreement, If 70 Million Is Lesser Than One Percent Of Net Proceeds \| Derecognition Of Warrants
Collaboration arrangements
Threshold Percentage Of Net Proceeds	1
Percentage Of Net Proceeds Payable	1

Accrued expenses and other cu_3

Accrued expenses and other current liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Accrued expenses and other current liabilities
Accruals for services provided by vendors-not yet billed	$ 11,180	$ 8,269
Personnel related accruals and liabilities	4,716	7,687
Contract liability	5,000	2,082
Total	$ 20,896	$ 18,038

Long-term debt (Details)

Long-term debt (Details) - USD ($) $ in Thousands	Jan. 29, 2021	Dec. 06, 2018	Mar. 31, 2021	Mar. 31, 2020	Dec. 15, 2021	Dec. 31, 2020	May 31, 2020
Long-term Debt
Proceeds from loan increment, net of debt issuance costs			$ 34,603
2016 Amended Facility \| Hercules \| Second Amended and Restated Loan and Security Agreement [Member]
Long-term Debt
Outstanding debt		$ 20,000
Back-end fees due							$ 1,000
2018 Amended Facility \| Hercules
Long-term Debt
Aggregate amount of Equity Financing			90,000
Foreign currency loss				$ 700
2018 Amended Facility \| Hercules \| Second Amended and Restated Loan and Security Agreement [Member]
Long-term Debt
Interest rate (as a percent)		8.85%
Back-end fee (as a percent)		4.95%
Proceeds from loan increment, net of debt issuance costs		$ 15,000
2018 Amended Facility \| Prime Rate \| Hercules \| Second Amended and Restated Loan and Security Agreement [Member]
Long-term Debt
Variable interest rate basis		8.85%
Discount rate (as a percent)		5.50%
2021 Amended Facility
Long-term Debt
Outstanding debt	$ 35,000
Proceed from drew down	$ 35,000
Interest rate (as a percent)	8.25%
Back-end fee (as a percent)	4.85%
Maximum borrowing capacity	$ 135,000
Additional unconditional borrowing capacity	$ 100,000
2021 Amended Facility \| Prime Rate
Long-term Debt
Variable interest rate basis	3.25%
2018 and 2021 Amended Facility \| Hercules
Long-term Debt
Foreign currency loss			$ 3,200
Venture debt loan facility \| 2018 Amended Facility
Aggregate maturities of loan
Long-term debt						$ 35,900
Venture debt loan facility \| 2018 Amended Facility \| Hercules
Long-term Debt
Interest expense recorded				$ 900
Venture debt loan facility \| 2018 and 2021 Amended Facility
Long-term Debt
Minimum cash and cash equivalents in U.S. bank accounts			65.00%
Assets pledged to secure facilities by directly or indirectly			$ 363,900
Assets not being pledged to secure facilities by directly or indirectly			97,600
Aggregate maturities of loan
Long-term debt			71,000
Venture debt loan facility \| 2018 and 2021 Amended Facility \| Hercules
Long-term Debt
Interest expense recorded			$ 1,500
Subsequent events. \| 2021 Amended Facility
Long-term Debt
Outstanding debt					$ 65,000
Subsequent events. \| 2021 Amended Facility \| Minimum
Long-term Debt
Outstanding debt					$ 20,000

Shareholders' equity (Details)

Shareholders' equity (Details) - USD ($) $ / shares in Units, $ in Thousands	Mar. 01, 2021	Mar. 31, 2021	Dec. 31, 2020
Aggregate offering price		$ 27,699
Additional paid-in-capital		1,049,850	$ 1,016,018
Sales Agreement with SVB Leerink LLC
Percentage of gross proceeds	3.00%
Net proceeds	$ 27,600
Sales Agreement with SVB Leerink LLC \| Direct Incremental Labor
Additional paid-in-capital		$ 1,000
Sales Agreement with SVB Leerink LLC \| Ordinary shares
Shares issued in connection with offering	859,885
Share price (in dollars per share)	$ 33.42
Sales Agreement with SVB Leerink LLC \| Maximum
Aggregate offering price	$ 200,000

Share-based compensation - Summ

Share-based compensation - Summary of share-based compensation expense and unrecognized costs (Details) - 2014 Plan - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Share-based compensation
Authorized shares	8,601,471
Increase in authorized shares	3,000,000
Share-based compensation expense	$ 5,754	$ 4,340
Unrecognized compensation costs	$ 62,985
Weighted-average remaining period for recognition (in years)	2 years 9 months 3 days
Research and development expenses
Share-based compensation
Share-based compensation expense	$ 2,674	2,382
Selling, general and administrative expense
Share-based compensation
Share-based compensation expense	3,080	1,958
Share options
Share-based compensation
Share-based compensation expense	$ 2,840	2,208
Outstanding of fully vested share options	3,331,646		2,659,279
Unrecognized compensation costs	$ 35,517
Weighted-average remaining period for recognition (in years)	3 years 1 month 2 days
Restricted share units ("RSUs")
Share-based compensation
Share-based compensation expense	$ 2,560	1,444
Unrecognized compensation costs	$ 26,227
Weighted-average remaining period for recognition (in years)	2 years 4 months 24 days
Performance share units ("PSUs")
Share-based compensation
Share-based compensation expense	$ 354	$ 688
Unrecognized compensation costs	$ 1,241
Weighted-average remaining period for recognition (in years)	9 months 29 days

Share-based compensation - Opti

Share-based compensation - Option activity and weighted-average assumptions (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Weighted average exercise price
Total weighted average grant date fair value of options issued during the period (in $ millions)	$ 15.8
Proceeds from option sales during the period (in $ millions)	$ 0.4
Weighted-average assumptions used to estimate fair value of share options granted during year
Risk free interest rate (as a percent)		1.44%
2014 Plan
Weighted average exercise price
Vesting period (in years)	4 years
Weighted-average assumptions used to estimate fair value of share options granted during year
Increase in authorized shares	3,000,000
2014 Plan \| Share options
Options
Outstanding at beginning of the period (in shares)	2,659,279
Granted (in shares)	734,683
Forfeited (in shares)	(40,440)
Expired (in shares)	(5,094)
Exercised (in shares)	(16,782)
Outstanding at end of the period (in shares)	3,331,646
Thereof, fully vested and exercisable at end of period (in shares)	1,718,923
Thereof, outstanding and expected to vest at end of period (in shares)	1,612,723
Weighted average exercise price
Outstanding at beginning of the period (in dollars per share)	$ 28.13
Granted (in dollars per share)	36.95
Forfeited (in dollars per share)	43.85
Expired (in dollars per share)	37.85
Exercised (in dollars per share)	23.34
Outstanding at end of period (in dollars per share)	29.90
Thereof, fully vested and exercisable at end of period (in dollars per share)	20.19
Outstanding and expected to vest at end of the period (in dollars per share)	$ 40.24
Weighted-average assumptions used to estimate fair value of share options granted during year
Expected volatility (as a percent)	75.00%	70.00%
Expected terms (in years)	10 years	10 years
Risk free interest rate, minimum (as a percent)	1.21%	1.44%
Risk free interest rate, maximum (as a percent)	1.71%
Expected dividend (as a percent)	0.00%	0.00%
2014 Plan \| Non-executive directors
Weighted average exercise price
Vesting period (in years)	1 year
2014 Plan \| One year from grant date
Weighted average exercise price
Vesting percentage per year	25.00%
Vesting period (in years)	1 year

Share-based compensation - RSU

Share-based compensation - RSU activity (Details) - 2014 Plan - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2021
Other disclosure
Vesting period (in years)		4 years
Non-executive directors
Other disclosure
Vesting period (in years)		1 year
Restricted share units ("RSUs")
Number of shares
Non-vested at beginning of period (in shares)		467,344
Restricted stock granted (in shares)		404,967
Vested (in shares)		(136,721)
Forfeited (in shares)		(15,938)
Non-vested at end of period (in shares)		719,652
Weighted average grant-date fair value
Non-vested at beginning of period (in dollars per share)		$ 43.56
Granted (in dollars per share)		36.96
Vested (in dollars per share)		38.63
Forfeited (in dollars per share)		43.46
Non-vested at end of period (in dollars per share)		$ 40.79
Other disclosure
Total weighted average grant date fair value of RSUs granted during the period (in millions)		$ 15,000
Restricted share units ("RSUs") \| Non-executive directors
Other disclosure
Vesting period (in years)	1 year
Minimum \| Restricted share units ("RSUs")
Other disclosure
Vesting period (in years)		1 year
Maximum \| Restricted share units ("RSUs")
Other disclosure
Vesting period (in years)		3 years

Share-based compensation - PSU

Share-based compensation - PSU activity (Details) - 2014 Plan	3 Months Ended
	Mar. 31, 2021$ / sharesshares
Other disclosure
Vesting period (in years)	4 years
Performance share units ("PSUs")
Number of shares
Non-vested at beginning of period (in shares) \| shares	212,614
Vested (in shares) \| shares	(132,368)
Forfeited (in shares) \| shares	(2,916)
Non-vested at end of period (in shares) \| shares	77,330
Weighted average grant-date fair value
Non-vested at beginning of period (in dollars per share) \| $ / shares	$ 42.32
Vested (in dollars per share) \| $ / shares	33.09
Forfeited (in dollars per share) \| $ / shares	57.56
Non-vested at end of period (in dollars per share) \| $ / shares	$ 57.56

Share-based compensation - Empl

Share-based compensation - Employee Share Purchase Plan - Narrative (Details) - ESPP - Employee Stock [Member] - shares	1 Months Ended	3 Months Ended
	Jun. 30, 2018	Mar. 31, 2021	Mar. 31, 2020
Share-based compensation
Ordinary shares available for issue	150,000	130,852	136,406
Discounted rate for purchase of shares	85.00%
Number of shares issued		1,174	1,801

Income taxes - Effective Tax Ra

Income taxes - Effective Tax Rate (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Income taxes
Net deferred tax asset	$ 0.2		$ 0
Effective income tax rate	0.50%	0.00%
Tax rate enacted in the Netherlands	25.00%
Effective tax rate for Dutch operations	0.00%

Basic and diluted earnings pe_3

Basic and diluted earnings per share (Details) - shares	3 Months Ended
Basic and diluted earnings per share (Details) - shares	Mar. 31, 2021	Mar. 31, 2020
Basic and diluted earnings per share
Total potential dilutive ordinary shares	4,143,357	13,916,001
BMS Warrants \| Bristol Myers Squibb
Basic and diluted earnings per share
Total potential dilutive ordinary shares		10,262,500
Stock options \| 2014 Plan
Basic and diluted earnings per share
Total potential dilutive ordinary shares	3,331,646	3,003,430
Stock options \| Previous option plan
Basic and diluted earnings per share
Total potential dilutive ordinary shares	14,000	14,000
Stock options \| ESPP
Basic and diluted earnings per share
Total potential dilutive ordinary shares	729	681
Non-vested and earned RSUs and PSUs
Basic and diluted earnings per share
Total potential dilutive ordinary shares	796,982	635,390

Subsequent events (Details)

Subsequent events (Details) - CSL Behring collaboration - USD ($) $ in Millions	May 07, 2021	Mar. 31, 2021	May 06, 2021
Subsequent events
Upfront Payment Received		$ 0
Subsequent events.
Subsequent events
Upfront Payment Received	$ 450
Regulatory and first commercial sales milestone payments to be received			$ 300
Commercial sales milestone payments to be received			$ 1,300