ADC Therapeutics (ADCT) 10-Q 6 Aug 24 2024 Q2 Quarterly report Financial data

Cover

Cover - shares	6 Months Ended
	Jun. 30, 2024	Aug. 01, 2024
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2024
Document Transition Report	false
Entity File Number	001-39071
Entity Registrant Name	ADC Therapeutics SA
Entity Incorporation, State or Country Code	V8
Entity Address, Address Line One	Biopôle
Entity Address, Address Line Two	Route de la Corniche 3B
Entity Address, Postal Zip Code	1066
Entity Address, City or Town	Epalinges
Entity Address, Country	CH
Country Region	41
City Area Code	21 653
Local Phone Number	02 00
Title of 12(g) Security	Common Shares, par value CHF 0.08 per share
Trading Symbol	ADCT
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		96,647,450
Amendment flag	false
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q2
Entity central index key	0001771910
Current Fiscal Year End Date	--12-31

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Current assets
Cash and cash equivalents	$ 300,119	$ 278,598
Accounts receivable, net	22,868	25,182
Inventory	15,191	16,177
Prepaid expenses and other current assets	17,181	16,334
Total current assets	355,359	336,291
Property and equipment, net	5,483	5,622
Operating lease right-of-use assets	9,685	10,511
Interest in joint venture	260	1,647
Other long-term assets	992	711
Total assets	371,779	354,782
Current liabilities
Accounts payable	10,708	15,569
Accrued expenses and other current liabilities	46,924	52,101
Total current liabilities	57,632	67,670
Deferred royalty obligation, long-term	316,211	303,572
Senior secured term loans	113,673	112,730
Operating lease liabilities, long-term	9,309	10,180
Other long-term liabilities	6,624	8,879
Total liabilities	503,449	503,031
Commitments and contingencies (See Note 13)
Shareholders’ equity (deficit)
Common shares, at CHF $0.08 par value Issued shares: 99,453,858 at June 30, 2024 and 89,041,946 December 31, 2023; outstanding shares: 96,469,641 at June 30, 2024 and 82,293,137 at December 31, 2023	8,233	7,312
Additional paid-in capital	1,279,296	1,180,545
Treasury shares At June 30, 2024: 2,984,217 and December 31, 2023: 6,748,809	(239)	(541)
Accumulated other comprehensive loss	(338)	(93)
Accumulated deficit	(1,418,622)	(1,335,472)
Total shareholders’ equity (deficit)	(131,670)	(148,249)
Total liabilities and shareholders’ equity (deficit)	$ 371,779	$ 354,782

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - SFr / shares	Jun. 30, 2024	Dec. 31, 2023
Statement of Financial Position [Abstract]
Common shares, par value (in CHF per share)	SFr 0.08	SFr 0.08
Common shares issued (in shares)	99,453,858	89,041,946
Common shares outstanding (in shares)	96,469,641	82,293,137
Treasury shares (in shares)	2,984,217	6,748,809

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Revenue
Product revenues, net	$ 17,030	$ 19,197	$ 34,878	$ 38,150
License revenues and royalties	380	86	585	125
Total revenue, net	17,410	19,283	35,463	38,275
Operating expense
Cost of product sales	(1,217)	(1,132)	(3,727)	(1,105)
Research and development	(24,295)	(31,342)	(50,030)	(69,717)
Selling and marketing	(10,701)	(14,456)	(22,091)	(29,807)
General and administrative	(10,238)	(12,002)	(22,269)	(27,505)
Total operating expense	(46,451)	(58,932)	(98,117)	(128,134)
Loss from operations	(29,041)	(39,649)	(62,654)	(89,859)
Other income (expense)
Interest income	3,253	2,372	6,201	4,547
Interest expense	(12,679)	(10,309)	(25,175)	(20,600)
Other, net	2,754	(5,067)	159	(4,234)
Total other expense, net	(6,672)	(13,004)	(18,815)	(20,287)
Loss before income taxes	(35,713)	(52,653)	(81,469)	(110,146)
Income tax (expense) benefit	(234)	4,498	(397)	3,980
Loss before equity in net losses of joint venture	(35,947)	(48,155)	(81,866)	(106,166)
Equity in net losses of joint venture	(597)	(767)	(1,284)	(2,130)
Net loss	$ (36,544)	$ (48,922)	$ (83,150)	$ (108,296)
Net loss per share
Net loss per share, basic (in dollars per share)	$ (0.38)	$ (0.60)	$ (0.93)	$ (1.33)
Net loss per share, diluted (in dollars per share)	$ (0.38)	$ (0.60)	$ (0.93)	$ (1.33)
Weighted average shares outstanding, basic (in shares)	95,691,245	81,471,127	89,121,783	81,140,287
Weighted average shares outstanding, diluted (in shares)	95,691,245	81,471,127	89,121,783	81,140,287

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Statement of Comprehensive Income [Abstract]
Net loss	$ (36,544)	$ (48,922)	$ (83,150)	$ (108,296)
Other comprehensive (loss) income:
Remeasurement of defined benefit plan	(81)	(40)	(81)	(79)
Currency translation differences	17	170	(61)	311
Other comprehensive (loss) income before share of other comprehensive loss in joint venture	(64)	130	(142)	232
Share of other comprehensive loss in joint venture	(73)	(444)	(103)	(700)
Other comprehensive loss	(137)	(314)	(245)	(468)
Total comprehensive loss	$ (36,681)	$ (49,236)	$ (83,395)	$ (108,764)

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS’ EQUITY (DEFICIT) - USD ($) $ in Thousands	Total	Common stock	Additional paid-in capital	Treasury stock	Accumulated other comprehensive (loss) income	Accumulated deficit
Beginning balance (in shares) at Dec. 31, 2022		89,041,946
Beginning balance at Dec. 31, 2022	$ 79,451	$ 7,312	$ 1,166,414	$ (679)	$ 1,823	$ (1,095,419)
Treasury stock, beginning balance (in shares) at Dec. 31, 2022				(8,399,419)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Loss for the period	(108,296)					(108,296)
Remeasurement of defined benefit pension liability	(79)				(79)
Foreign currency translation adjustment	311				311
Other comprehensive (loss) income before share of other comprehensive loss in joint venture	232				232
Share of other comprehensive loss in joint venture	(700)				(700)
Other comprehensive loss	(468)				(468)
Total comprehensive loss	(108,764)				(468)	(108,296)
Vestings of RSUs	0		(111)	$ 111
Vestings of RSUs (in shares)				1,269,106
Issuance of shares, 2022 Employee Stock Purchase Plan	425		414	$ 11
Issuance of shares, 2022 Employee Stock Purchase Plan (in shares)				130,348
Share-based compensation expense	9,192		9,192
Common stock, increase (decrease) (in shares)		0		1,399,454
Stockholders' equity, excluding OCI, increase (decrease)	9,617	$ 0	9,495	$ 122
Ending balance (in shares) at Jun. 30, 2023		89,041,946
Ending balance at Jun. 30, 2023	(19,696)	$ 7,312	1,175,909	$ (557)	1,355	(1,203,715)
Treasury stock, ending balance (in shares) at Jun. 30, 2023				(6,999,965)
Beginning balance (in shares) at Dec. 31, 2022		89,041,946
Beginning balance at Dec. 31, 2022	$ 79,451	$ 7,312	1,166,414	$ (679)	1,823	(1,095,419)
Treasury stock, beginning balance (in shares) at Dec. 31, 2022				(8,399,419)
Ending balance (in shares) at Dec. 31, 2023	82,293,137	89,041,946
Ending balance at Dec. 31, 2023	$ (148,249)	$ 7,312	1,180,545	$ (541)	(93)	(1,335,472)
Treasury stock, ending balance (in shares) at Dec. 31, 2023	(6,748,809)			(6,748,809)
Beginning balance (in shares) at Mar. 31, 2023		89,041,946
Beginning balance at Mar. 31, 2023	$ 28,422	$ 7,312	1,174,879	$ (645)	1,669	(1,154,793)
Treasury stock, beginning balance (in shares) at Mar. 31, 2023				(8,014,180)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Loss for the period	(48,922)					(48,922)
Remeasurement of defined benefit pension liability	(40)				(40)
Foreign currency translation adjustment	170				170
Other comprehensive (loss) income before share of other comprehensive loss in joint venture	130				130
Share of other comprehensive loss in joint venture	(444)				(444)
Other comprehensive loss	(314)				(314)
Total comprehensive loss	(49,236)				(314)	(48,922)
Vestings of RSUs	0		(88)	$ 88
Vestings of RSUs (in shares)				1,014,215
Share-based compensation expense	1,118		1,118
Common stock, increase (decrease) (in shares)				1,014,215
Stockholders' equity, excluding OCI, increase (decrease)	1,118		1,030	$ 88
Ending balance (in shares) at Jun. 30, 2023		89,041,946
Ending balance at Jun. 30, 2023	$ (19,696)	$ 7,312	1,175,909	$ (557)	1,355	(1,203,715)
Treasury stock, ending balance (in shares) at Jun. 30, 2023				(6,999,965)
Beginning balance (in shares) at Dec. 31, 2023	82,293,137	89,041,946
Beginning balance at Dec. 31, 2023	$ (148,249)	$ 7,312	1,180,545	$ (541)	(93)	(1,335,472)
Treasury stock, beginning balance (in shares) at Dec. 31, 2023	(6,748,809)			(6,748,809)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Loss for the period	$ (83,150)					(83,150)
Remeasurement of defined benefit pension liability	(81)				(81)
Foreign currency translation adjustment	(61)				(61)
Other comprehensive (loss) income before share of other comprehensive loss in joint venture	(142)				(142)
Share of other comprehensive loss in joint venture	(103)				(103)
Other comprehensive loss	(245)				(245)
Total comprehensive loss	(83,395)				(245)	(83,150)
Vestings of RSUs	0		(42)	$ 42
Vestings of RSUs (in shares)				502,929
Exercise of options	$ 74		72	$ 2
Exercise of options (in shares)	31,988			31,988
Issuance of shares, 2022 Employee Stock Purchase Plan	$ 323		305	$ 18
Issuance of shares, 2022 Employee Stock Purchase Plan (in shares)				229,675
Issuance of shares, underwritten offering, net of transaction costs	60,506	$ 921	59,345	$ 240
Issuance of shares, underwritten offering, net of transaction costs (in shares)		10,411,912		3,000,000
Issuance of warrants, underwritten offering, net of transaction costs	36,925		36,925
Share-based compensation expense	2,146		2,146
Common stock, increase (decrease) (in shares)		10,411,912		3,764,592
Stockholders' equity, excluding OCI, increase (decrease)	$ 99,974	$ 921	98,751	$ 302
Ending balance (in shares) at Jun. 30, 2024	96,469,641	99,453,858
Ending balance at Jun. 30, 2024	$ (131,670)	$ 8,233	1,279,296	$ (239)	(338)	(1,418,622)
Treasury stock, ending balance (in shares) at Jun. 30, 2024	(2,984,217)			(2,984,217)
Beginning balance (in shares) at Mar. 31, 2024		89,041,946
Beginning balance at Mar. 31, 2024	$ (194,449)	$ 7,312	1,181,020	$ (502)	(201)	(1,382,078)
Treasury stock, beginning balance (in shares) at Mar. 31, 2024				(6,264,720)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Loss for the period	(36,544)					(36,544)
Remeasurement of defined benefit pension liability	(81)				(81)
Foreign currency translation adjustment	17				17
Other comprehensive (loss) income before share of other comprehensive loss in joint venture	(64)				(64)
Share of other comprehensive loss in joint venture	(73)				(73)
Other comprehensive loss	(137)				(137)
Total comprehensive loss	(36,681)				(137)	(36,544)
Vestings of RSUs	0		(22)	$ 22
Vestings of RSUs (in shares)				254,899
Exercise of options	41		40	$ 1
Exercise of options (in shares)				25,604
Issuance of shares, underwritten offering, net of transaction costs	60,506	$ 921	59,345	$ 240
Issuance of shares, underwritten offering, net of transaction costs (in shares)		10,411,912		3,000,000
Issuance of warrants, underwritten offering, net of transaction costs	36,925		36,925
Share-based compensation expense	1,988		1,988
Common stock, increase (decrease) (in shares)		10,411,912		3,280,503
Stockholders' equity, excluding OCI, increase (decrease)	$ 99,460	$ 921	98,276	$ 263
Ending balance (in shares) at Jun. 30, 2024	96,469,641	99,453,858
Ending balance at Jun. 30, 2024	$ (131,670)	$ 8,233	$ 1,279,296	$ (239)	$ (338)	$ (1,418,622)
Treasury stock, ending balance (in shares) at Jun. 30, 2024	(2,984,217)			(2,984,217)

CONDENSED CONSOLIDATED STATEM_4

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Cash used in operating activities
Net loss	$ (36,544)	$ (48,922)	$ (83,150)	$ (108,296)
Adjustments to reconcile net loss to net cash used in operations:
Deferred income taxes			0	(5,172)
Share-based compensation expense			2,146	9,192
Accretion expense of deferred royalty obligation			13,790	5,346
Amortization of debt discount, senior secured term loan			943	1,503
Cumulative catch-up adjustment, deferred royalty obligation	(263)	5,417	(526)	5,288
Write-downs of inventory	288	727	1,036	780
Depreciation	326	273	657	536
Amortization of operating lease right-of-use assets			1,024	999
Share of results in joint venture	597	767	1,284	2,130
Warrant obligations, increase (decrease) in fair value			838	(636)
Other			(240)	18
Changes in operating assets and liabilities:
Accounts receivable, net			2,314	49,089
Inventory			(50)	(2,400)
Other current assets			(859)	4,930
Other long-term assets			(287)	200
Accounts payable			(6,083)	(687)
Accrued expenses and other short-term liabilities			(5,732)	(15,588)
Operating lease liabilities			(1,028)	(714)
Other long-term liabilities			(3,017)	3,102
Net cash used in operating activities			(76,940)	(50,380)
Cash flows from investing activities
Payment for purchases of property and equipment			(561)	(2,228)
Net cash used in investing activities			(561)	(2,228)
Cash flows provided by financing activities
Proceeds from common shares, 2024 Equity Offering, net of transaction costs			61,731	0
Proceeds from 2024 Pre-Funded Warrants, net of transaction costs			36,925	0
Proceeds from deferred royalty transaction, net of transaction costs			0	73,102
Proceeds from share issuance under stock purchase plan			323	425
Proceeds from the exercise of stock options			74	0
Net cash provided by financing activities			99,053	73,527
Net increase in cash and cash equivalents			21,552	20,919
Exchange (losses)/gains on cash and cash equivalents			(31)	150
Cash and cash equivalents at beginning of period			278,598	326,441	$ 326,441
Cash and cash equivalents at end of period	$ 300,119	$ 347,510	300,119	347,510	$ 278,598
Supplemental Cash Flow Information:
Interest paid			7,874	7,522
Interest received			7,635	5,167
Payments made under royalty financing transaction			2,569	6,230
Supplemental Non-Cash Investing and Financing Activities:
Transaction costs recorded in Accounts payable and other current liabilities			1,225	0
Capital expenditures recorded in Accounts payable and Accrued expenses and other current liabilities			$ 0	$ 270

Description of Business and Org

Description of Business and Organization	6 Months Ended
	Jun. 30, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business and Organization	Description of Business and Organization ADC Therapeutics is a leading, commercial-stage global pioneer in the field of antibody drug conjugates (“ADCs”) committed to advancing its proprietary ADC technology platform to transform the treatment paradigm for patients with hematologic malignancies and solid tumors. Since its inception, the Company has devoted its resources to developing a validated and differentiated technology platform with multiple payloads and targets, a robust next-generation research and development toolbox, and specialized end-to-end capabilities. The Company generates sales from its flagship product, ZYNLONTA, which is currently approved in the U.S. for the treatment of relapsed or refractory diffuse large B-cell lymphoma (“DLBCL”) in the third-line setting and has also been granted conditional marketing authorization in Europe. Additionally, the Company is seeking to expand ZYNLONTA into earlier lines of therapy and indolent lymphomas, and is committed to advancing its portfolio and pipeline through its continued research, development, regulatory and commercialization activities. The Company was incorporated on June 6, 2011 under the laws of Switzerland, with its registered office located at Route de la Corniche 3B, 1066 Epalinges, Switzerland. The Company has three wholly-owned subsidiaries: ADC Therapeutics America, Inc. (“ADCT America”), which was incorporated in Delaware, USA on December 10, 2014, ADC Therapeutics (UK) Ltd (“ADCT UK”), which was incorporated in England on December 12, 2014 and ADC Therapeutics (NL) B.V. which was incorporated in the Netherlands on February 25, 2022. The Company and its three subsidiaries form the ADCT Group (the “Group”). All references to “ADC Therapeutics,” “the Company", “we,” “us,” and “our” refer to ADC Therapeutics SA and its unaudited condensed consolidated subsidiaries unless otherwise indicated.

Summary of Significant Accounti

Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2024
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Basis of preparation and principles of consolidation These accompanying unaudited condensed consolidated financial statements, which include the accounts of the Company and its wholly-owned subsidiaries, have been prepared following the requirements of the U.S. Securities and Exchange Commission for interim reporting. As permitted under those rules, certain footnotes and other financial information that are normally required by U.S. generally accepted accounting principles, or U.S. GAAP, can be condensed or omitted. All intercompany transactions and balances have been eliminated in consolidation. The information included in this Quarterly Report on Form 10‑Q should be read in conjunction with our annual audited consolidated financial statements and accompanying notes included in the Company’s Annual Report on Form 10‑K for the year ended December 31, 2023. In the opinion of management, these condensed consolidated financial statements have been prepared on the same basis as the annual audited consolidated financial statements and include all adjustments, consisting only of normal recurring adjustments, considered necessary for the fair statement of our financial position and operating results. The results for the three and six months ended June 30, 2024 are not necessarily indicative of the results to be expected for the year ending December 31, 2024, for any other interim period or for any future period. The Company’s significant accounting policies have not changed substantially from those previously described in the Company’s Annual Report on Form 10‑K for the year ended December 31, 2023. The Company is managed and operated as one business segment, focused on the global development and commercialization of targeted ADC cancer therapies. A single management team that reports to the chief operating decision-maker, the Chief Executive Officer, comprehensively manages and allocates resources at the global corporate level. Accordingly, the Company views its business and manages its operations as a single operating segment. Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses, and related disclosures in the unaudited condensed consolidated financial statements and accompanying notes. Management bases its estimates on historical experience and on assumptions believed to be reasonable under the circumstances. Actual results could differ materially from those estimates. Going Concern We are responsible for evaluating, and providing disclosure of uncertainties about, our ability to continue as a going concern. As of June 30, 2024, we had cash and cash equivalents of $300.1 million. Based on our evaluation, we concluded there is no substantial doubt about our ability to continue as a going concern within one year from the date the unaudited condensed consolidated financial statements were issued. Recent Accounting Pronouncements New accounting pronouncements which have been adopted There are no accounting pronouncements that the Company has recently adopted. Issued but not yet adopted In November 2023, the FASB amended guidance in ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. The revised guidance requires that a public entity disclose significant segment expenses regularly reviewed by the chief operating decision maker (CODM), including public entities with a single reportable segment. The amended guidance is effective for fiscal years beginning in January 2024 and interim periods beginning January 2025 on a retrospective basis. Early adoption is permitted. The Company is currently evaluating the effect that adoption of ASU 2023-07 will have on its consolidated financial statements. In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures. The ASU requires the annual financial statements to include consistent categories and greater disaggregation of information in the rate reconciliation, and income taxes paid disaggregated by jurisdiction. ASU 2023-09 is effective for the Company’s annual reporting periods beginning in January 2025. Adoption is either with a prospective method or a fully retrospective method of transition. Early adoption is permitted. The Company is currently evaluating the effect that adoption of ASU 2023-09 will have on its consolidated financial statements.

Fair value measurements

Fair value measurements	6 Months Ended
	Jun. 30, 2024
Fair Value Disclosures [Abstract]
Fair value measurements	Fair value measurements The carrying amount of Cash and cash equivalents, Accounts Receivable, net and Accounts payable is a reasonable approximation of fair value due to the short-term nature of these assets and liabilities. Financial liabilities that are not measured at fair value on a recurring basis include our senior secured term loan. The estimated fair value of debt is based on Level 2 inputs, including our understanding of current market rates we could obtain for similar loans. The Deerfield warrants, which are measured at fair value on a recurring basis, were as follows as of June 30, 2024 and December 31, 2023: (in thousands) Total Quoted prices in active markets for identical assets and liabilities (Level 1) Other observable inputs (Level 2) Significant unobservable inputs (Level 3) June 30, 2024: Deerfield warrant obligation $ 1,134 $ — $ 1,134 $ — Total $ 1,134 $ — $ 1,134 $ — (in thousands) Total Quoted prices in active markets for identical assets and liabilities (Level 1) Other observable inputs (Level 2) Significant unobservable inputs (Level 3) December 31, 2023: Deerfield warrant obligation $ 296 $ — $ 296 $ — Total $ 296 $ — $ 296 $ — Fair values must be estimated at the end of each reporting period with regard to the Deerfield warrants. The approach to valuation follows the fair value principle, and the key input factors are described for the Deerfield warrants in note 10, "Deerfield warrants." A Black-Scholes model was used to calculate the fair values. There were no transfers between the respective levels during the period.

Inventory

Inventory	6 Months Ended
	Jun. 30, 2024
Inventory Disclosure [Abstract]
Inventory	Inventory As of June 30, 2024 and December 31, 2023 inventory consisted of the following: (in thousands) June 30, 2024 December 31, 2023 Work in progress $ 15,123 $ 16,095 Finished goods 68 82 Total inventory, net $ 15,191 $ 16,177

Property and equipment

Property and equipment	6 Months Ended
	Jun. 30, 2024
Property, Plant and Equipment [Abstract]
Property and equipment	Property and equipment Property and equipment as of June 30, 2024 and December 31, 2023 consisted of the following: (in thousands) June 30, 2024 December 31, 2023 Leasehold improvements $ 3,905 $ 3,953 Laboratory equipment 4,154 3,652 Office equipment 977 1,119 Hardware and computer software 1,138 1,173 10,174 9,897 Less: accumulated depreciation (4,691) (4,275) Property and equipment, net $ 5,483 $ 5,622

Interest in joint venture

Interest in joint venture	6 Months Ended
	Jun. 30, 2024
Equity Method Investments and Joint Ventures [Abstract]
Interest in joint venture	Interest in joint venture On December 14, 2020, the Company formed a new joint venture company, Overland ADCT BioPharma, with Overland Pharmaceuticals (“Overland”) to develop and commercialize ZYNLONTA, and three of the Company’s ADC product candidates, ADCT-601, ADCT-602 and ADCT-901 (collectively, the “Licensed Products”), in greater China and Singapore (the “Territory”). The table below provides a rollforward of the Company’s interest in Overland ADCT BioPharma as of June 30, 2024 and December 31, 2023. (in thousands) Interest in joint venture January 1, 2023 $ 7,613 Share of comprehensive loss in joint venture (5,966) December 31, 2023 $ 1,647 Share of comprehensive loss in joint venture (1,387) June 30, 2024 $ 260

Income taxes

Income taxes	6 Months Ended
	Jun. 30, 2024
Income Tax Disclosure [Abstract]
Income taxes	Income taxes Income tax expense for the three and six months ended June 30, 2024 was $0.2 million and $0.4 million, respectively, relative to loss before income taxes of $35.7 million and $81.5 million, respectively. The income tax benefit for the three and six months ended June 30, 2023 was $4.5 million and $4.0 million, respectively, relative to loss before income taxes of $52.7 million and $110.1 million, respectively. The expense for the three and six months ended June 30, 2024 is the result of income generated by our UK operations for which tax expense has been recognized based on a full year estimated income tax liability, and the inability to recognize benefit on losses in the U.S. and Switzerland. Whereas the benefit for the three and six months ended June 30, 2023 was the result of income generated in the U.S. and UK. The decrease in income for the US operations is due to a change in the Company operating and transfer pricing model which was implemented in October 2023. We retain a full valuation allowance against all deferred tax assets, and each reporting period, we evaluate the need for a valuation allowance on our deferred tax assets by jurisdiction and adjust our estimates as more information becomes available.

Accrued expenses and other curr

Accrued expenses and other current liabilities	6 Months Ended
	Jun. 30, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accrued expenses and other current liabilities	Accrued expenses and other current liabilities Accrued expenses and other current liabilities consist of the following: (in thousands) June 30, 2024 December 31, 2023 Accrued R&D costs $ 18,304 $ 24,902 Accrued payroll and benefits 8,088 12,693 Gross-to-net sales adjustments, short-term 8,180 1,543 Operating lease liabilities, short-term 1,415 1,467 Other 10,937 11,496 $ 46,924 $ 52,101

Senior secured term loan facili

Senior secured term loan facility	6 Months Ended
	Jun. 30, 2024
Debt Disclosure [Abstract]
Senior secured term loan facility	Senior secured term loan facility On August 15, 2022, the Company, ADCT UK and ADCT America entered into the Loan Agreement, pursuant to which the Company may borrow up to $175.0 million principal amount of secured term loans, including (i) a First Tranche and (ii) Future Tranches. On August 15, 2022, the Company drew down $120.0 million principal amount of term loans under the Loan Agreement. On August 15, 2022, the Company also issued to the lenders under the Loan Agreement warrants to purchase an aggregate of 527,295 common shares, which warrants have an exercise price of $8.30 per share. Each warrant is exercisable, on a cash or a cashless basis, at the option of the holder at any time on or prior to August 15, 2032. The warrants are freestanding financial instruments that are indexed to the Company’s common stock and meet all other conditions for equity classification under ASC 480 and ASC 815. Accordingly, these warrants are recognized in equity and accounted for as a component of additional paid-in capital at the time of issuance. On August 15, 2022, the Company also entered into the Share Purchase Agreement with the lenders under the Loan Agreement to purchase 733,568 common shares of the Company. For the three and six months ended June 30, 2024, the Company recorded interest expense on the senior secured term loan in the amount of $4,413 and $8,816, respectively, and $4,480 and $9,020 for the three and six months ended June 30, 2023, respectively, which was recorded in interest expense in the unaudited condensed consolidated statements of operations. The effective interest rate (“EIR”) at June 30, 2024 was 16.83%. The following table provides a summary of the interest expense for the Company’s senior secured term loan for the three months ended June 30, 2024 and 2023: Three months ended June 30, Six months ended June 30, 2024 2023 2024 2023 Contractual interest expense $ 3,973 $ 3,807 $ 7,873 $ 7,517 Amortization of debt discount 440 673 943 1,503 Total $ 4,413 $ 4,480 $ 8,816 $ 9,020 The amount at which the senior secured term loan is presented as a liability in the unaudited condensed consolidated balance sheets represents the net present value of all future cash outflows associated with the loan discounted at the EIR. The carrying value of the senior secured term loan is $113.7 million and $112.7 million as of June 30, 2024 and December 31, 2023, respectively. Contractual payments due under our senior secured term loans, including exit fees are as follows (in thousands): 2024 (remainder) $ — 2025 — 2026 3,090 2027 9,330 2028 12,480 Thereafter 99,840 Total $ 124,740

Deerfield warrants

Deerfield warrants	6 Months Ended
	Jun. 30, 2024
Other Liabilities Disclosure [Abstract]
Deerfield warrants	Deerfield warrants Pursuant to the Exchange Agreement with Deerfield entered into on August 15, 2022, the Company issued warrants to purchase an aggregate of 4,412,840 common shares. The warrants consist of warrants to purchase an aggregate of 2,631,578 common shares at an exercise price of $24.70 per share and warrants to purchase an aggregate of 1,781,262 common shares at an exercise price of $28.07 per share. Each warrant is exercisable, on a cash or a cashless basis, at the option of the holder, at any time on or prior to May 19, 2025. The warrant obligation, which is included in other long-term liabilities in the unaudited condensed consolidated balance sheets, is remeasured to fair value at the end of each reporting period. Changes in the fair value (gains or losses) of the warrant obligation at the end of each period are recorded in the unaudited condensed consolidated statements of operations. During the three and six months ended June 30, 2024, the Company recognized income (expense) of $2,230 and $(838), respectively, and $20 and $636 for the three and six months ended June 30, 2023, respectively, as a result of changes in the fair value of the warrant obligation. The fair value of the warrant obligation as of June 30, 2024 and December 31, 2023 was $1,134 and $296, respectively. The increase in fair value of the warrant obligation from December 31, 2023 to June 30, 2024 was primarily due to the increase in the fair value of the underlying shares during the respective period. This amount was recorded to Other, net in the unaudited condensed consolidated statements of operations. See note 16, "Other income (expense)" for further information. The Company used a third-party valuation firm to assist in calculating the fair value of the Deerfield warrant obligation, using the Black-Scholes option-pricing model. Key inputs for the valuation of the warrant obligation as of June 30, 2024 and December 31, 2023 were as follows: As of As of June 30, 2024 December 31, 2023 Exercise price in $ 24.70 and 28.07 24.70 and 28.07 Share price in $ 3.16 1.66 Risk-free interest rate 5.1 % 4.6 % Expected volatility 140.6 % 116.0 % Expected term (months) 10.7 months 16.7 months Dividend yield — — Black-Scholes value in $ 0.27 and 0.23 0.07 and 0.06

Deferred royalty obligation

Deferred royalty obligation	6 Months Ended
	Jun. 30, 2024
Other Liabilities Disclosure [Abstract]
Deferred royalty obligation	Deferred royalty obligation On August 25, 2021, the Company entered into a royalty purchase agreement with certain entities managed by HCR for up to $325.0 million. Under the terms of the agreement, the Company received gross proceeds of $225.0 million upon closing (the “First Investment Amount”) and received an additional $75.0 million during the year ended December 31, 2023 upon the first commercial sale of ZYNLONTA in the United Kingdom or any European Union country (the “Second Investment Amount”) and together with the First Investment Amount, the “Investment Amount”). The table below provides a rollforward of the Company’s debt obligation relating to the royalty purchase agreement. (in thousands) Liability balance at January 1, 2023 $ 222,277 Plus: Additional proceeds from the sale of future royalties 75,000 Less: Transaction costs 1,898 Less: royalty payments 8,709 Plus: interest expense 27,915 Less: cumulative catch-up adjustment, Other, net 4,972 Liability balance at December 31, 2023 309,613 Less: royalty payments 2,569 Plus: interest expense 16,359 Less: cumulative catch-up adjustment, Other, net 526 Liability balance at June 30, 2024 $ 322,877

Pension and post-retirement ben

Pension and post-retirement benefit obligations	6 Months Ended
	Jun. 30, 2024
Retirement Benefits [Abstract]
Pension and post-retirement benefit obligations	Pension and post-retirement benefit obligations The pension plan for Swiss employees is a defined benefit pension plan. The Company contracted with the Swiss Life Collective BVG Foundation based in Zurich for the provision of occupational benefits. All benefits in accordance with the regulations are reinsured in their entirety with Swiss Life SA within the framework of the corresponding contract. This pension solution fully reinsures the risks of disability, death and longevity with Swiss Life. Swiss Life invests the vested pension capital and provides a 100% capital and interest guarantee. The pension plan is entitled to an annual bonus from Swiss Life comprising the effective savings, risk and cost results. Although, as is the case with many Swiss pension plans, the amount of ultimate pension benefit is not defined, certain legal obligations of the plan create constructive obligations on the employer to pay further contributions to fund an eventual deficit; this results in the plan nevertheless being accounted for as a defined benefit plan. The net periodic benefit cost for the three and six months ended June 30, 2024 and 2023 is as follows: Three months ended June 30, Six months ended June 30, (in thousands) 2024 2023 2024 2023 Net periodic benefit cost: Service cost $ 183 $ 275 $ 347 $ 447 Interest cost 37 75 75 149 Expected return on plan assets (59) (83) (118) (165) Amortization of prior service cost (40) (40) (81) (79) Net periodic benefit cost $ 121 $ 227 $ 223 $ 352 The components of net periodic benefit cost are included in operating expense on the unaudited condensed consolidated statements of operations.

Commitments and contingencies

Commitments and contingencies	6 Months Ended
	Jun. 30, 2024
Commitments and Contingencies Disclosure [Abstract]
Commitments and contingencies	Commitments and contingencies Manufacturing Commitments Some of our inventory components require long lead times to manufacture. Therefore, we make long-term investments in our supply chain in order to ensure we have enough drug product to meet current and future revenue forecasts. Third party manufacturing agreements include non-cancelable obligations related to the supply of ZYNLONTA and the company’s product candidates. There have been no material changes related to our non-cancelable obligations under these arrangements as disclosed in our Annual Report on Form 10-K for the year ended December 31, 2023. Contingent liabilities

Shareholders' equity

Shareholders' equity	6 Months Ended
	Jun. 30, 2024
Equity [Abstract]
Shareholders' equity	Shareholders’ equity 2024 Equity Offering In May 2024, the Company completed an underwritten offering of equity securities in which 13,411,912 of the Company’s common shares were sold to public investors at a price of $4.90 per share and pre-funded warrants (the “2024 Pre-Funded Warrants”) to purchase 8,163,265 of the Company’s common shares were sold to public investors at a price of $4.81 per pre-funded warrant, which equals the per share 2024 Equity Offering price, less the CHF 0.08 exercise price for each pre-funded warrant (collectively, the “2024 Equity Offering”). Gross proceeds from the 2024 Equity Offering were approximately $105.0 million, and, after giving effect to $7.6 million of transaction costs related to the offering, net proceeds were approximately $97.4 million. The 2024 Pre-Funded Warrants are exercisable, on a cash basis (or, if there is no registration statement and current prospectus covering the issuance of the shares upon exercise, then on a cashless basis), at the option of the holder after the date of issuance until the tenth anniversary of their original issuance. At any time during the last 90 days of the term, the holder may exchange the Pre-Funded Warrant for, and we will issue, a new pre-funded warrant for the number of common shares then remaining under the Pre-Funded Warrant. The Pre-Funded Warrants have certain limitations on exercise, including (i) any exercise must be for at least 50,000 common shares (or, if less, the remaining common shares available for purchase under the Pre-Funded Warrants), (ii) a holder cannot exercise for any amount that would cause such holder’s beneficial ownership of our common shares to exceed 9.99% (or 19.99% with 61-days’ notice to us), and (iii) cashless exercise is not available in certain circumstances as specified in the Pre-Funded Warrants. The warrants contain customary anti-dilution adjustments and will entitle holders to receive any dividends or other distributions paid on the underlying common shares prior to their expiration on an as-exercised basis. Accounting for the 2024 Equity Offering and Pre-Funded Warrants The Company has accounted for the common shares and 2024 Pre-funded Warrants described above each as freestanding financial instruments. The common shares were issued from the Company’s share capital and treasury shares at par value. The common shares were recorded as $60.5 million to equity for the issuance of the common shares, net of transaction costs accrued and paid, and an increase in cash and cash equivalents. The warrants are freestanding financial instruments that are indexed to the Company’s common stock and meet all other conditions for equity classification under ASC 480 and ASC 815, including the warrant holders cannot require “net cash settlement” in a circumstance outside of the Company’s control, and there is sufficient authorized and unissued shares to settle the warrants. Accordingly, these warrants are recognized as $36.9 million in equity and accounted for as a component of additional paid-in capital at the time of issuance, net of transaction costs paid, and an increase in cash and cash equivalents.

Revenue

Revenue	6 Months Ended
	Jun. 30, 2024
Revenue from Contract with Customer [Abstract]
Revenue	Revenue The table below provides a disaggregation of revenues by type and customer location for the three and six months ended June 30, 2024 and 2023: Three months ended June 30, Six months ended June 30, (in thousands) 2024 2023 2024 2023 Types of goods and services Product revenue, net $ 17,030 $ 19,197 $ 34,878 $ 38,150 Royalties 380 86 585 125 Total revenue $ 17,410 $ 19,283 $ 35,463 $ 38,275 Customer Location U.S. $ 17,030 $ 19,197 $ 34,878 $ 38,150 EMEA (1) 380 86 585 125 Total revenue $ 17,410 $ 19,283 $ 35,463 $ 38,275 (1) Europe, the Middle East and Africa Product revenue, net The table below provides a rollforward of the Company’s accruals related to the GTN sales adjustments for the three and six months ended June 30, 2024: (in thousands) Discarded Drug Rebate Other Adjustments Total Balance as of April 1, 2024 $ 9,393 $ 3,768 $ 13,161 GTN accruals for current period 1,858 3,759 5,617 Prior period adjustments — (791) (791) Credits, payments and reclassifications — (3,479) (3,479) Balance as of June 30, 2024 $ 11,251 $ 3,257 $ 14,508 Balance as of January 1, 2024 $ 7,391 $ 3,946 $ 11,337 GTN accruals for current period 3,904 8,217 12,121 Prior period adjustments (44) (1,020) (1,064) Credits, payments and reclassifications — (7,886) (7,886) Balance as of June 30, 2024 $ 11,251 $ 3,257 $ 14,508 The table below provides a rollforward of the Company’s accruals related to the GTN sales adjustments for the three and six months ended June 30, 2023: (in thousands) Discarded Drug Rebate Other Adjustments Total Balance as of April 1, 2023 $ 1,316 $ 3,046 $ 4,362 GTN accruals for current period 1,485 4,298 5,783 Prior period adjustments — (229) (229) Credits, payments and reclassifications — (4,182) (4,182) Balance as of June 30, 2023 $ 2,801 $ 2,933 $ 5,734 Balance as of January 1, 2023 $ — $ 3,746 $ 3,746 GTN accruals for current period 2,801 8,598 11,399 Prior period adjustments — (877) (877) Credits, payments and reclassifications — (8,534) (8,534) Balance as of June 30, 2023 $ 2,801 $ 2,933 $ 5,734 The table below provides the classification of the accruals related to the GTN sales adjustment included in the Company’s unaudited condensed consolidated balance sheets as of June 30, 2024 and December 31, 2023. (in thousands) June 30, 2024 December 31, 2023 Accounts receivable, net $ 2,424 $ 2,403 Other current and non-current liabilities 12,084 8,934 $ 14,508 $ 11,337 Customers from which we derive more than 10% of our total product revenues for the three and six months ended June 30, 2024 and 2023 are as follows: Three months ended June 30, Six months ended June 30, 2024 2023 2024 2023 McKesson 37 % 38 % 40 % 38 % AmerisourceBergen Corporation 35 % 37 % 36 % 37 % Cardinal Health 28 % 25 % 24 % 25 %

Other income (expense)

Other income (expense)	6 Months Ended
	Jun. 30, 2024
Other Income and Expenses [Abstract]
Other income (expense)	Other income (expense) Interest Income Interest income includes interest received from banks on our cash balances. Interest income was $3.3 million and $6.2 million for the three and six months ended June 30, 2024, respectively, and $2.4 million and $4.5 million for the three and six months ended June 30, 2023, respectively. Interest Expense The components of Interest expense for the three and six months ended June 30, 2024 and 2023 are as follows: Three months ended June 30, Six months ended June 30, (in thousands) 2024 2023 2024 2023 Deferred royalty obligation interest expense $ 8,266 $ 5,829 $ 16,359 $ 11,575 Effective interest expense on senior secured term loan facility 4,413 4,480 8,816 9,020 Other interest expense — — — 5 Interest expense $ 12,679 $ 10,309 $ 25,175 $ 20,600 Other, net The components of Other, net for the three and six months ended June 30, 2024 and 2023 are as follows: Three months ended June 30, Six months ended June 30, (in thousands) 2024 2023 2024 2023 Deerfield warrant obligation, change in fair value income (expense) $ 2,230 $ 20 $ (838) $ 636 Cumulative catch-up adjustment income (expense), deferred royalty obligation 263 (5,417) 526 (5,288) Exchange differences (loss) gain (59) 15 (96) (37) R&D tax credit 320 315 567 455 Other, net $ 2,754 $ (5,067) $ 159 $ (4,234)

Share-based compensation

Share-based compensation	6 Months Ended
	Jun. 30, 2024
Share-Based Payment Arrangement [Abstract]
Share-based compensation	Share-based compensation The Company has adopted various share-based compensation incentive plans. Under these plans the Company may at its discretion grant to the plan participants, such as directors, certain employees, and service providers awards in the form of restricted shares and restricted share units (“RSUs”), share options, share appreciation rights, performance awards and other share-based awards. The 2019 Equity Incentive Plan was adopted in November 2019 while the Conditional Share Capital Plan and the Inducement Plan were adopted in December 2023. 2019 Equity Incentive Plan In November 2019, the Company adopted the 2019 Equity Incentive Plan. Under the 2019 Equity Incentive Plan, the Company may at its discretion grant to plan participants, such as directors, certain employees and service providers, awards in the form of restricted shares and RSUs, share options, share appreciation rights, performance awards and other share-based awards. The Company has reserved 17,741,355 common shares for future issuance under the 2019 Equity Incentive Plan (including share-based equity awards granted to date less awards forfeited). As of June 30, 2024, the Company has 4,806,185 common shares available for the future issuance of share-based equity awards. As of June 30, 2024 and December 31, 2023, the cumulative amount recorded as a net increase to additional paid-in capital within equity on the unaudited condensed consolidated balance sheets in respect of the 2019 Equity Incentive Plan was $157,773 and $157,906, respectively. The amounts of expense (reversal) recognized for all awards for services received during the three and six months ended June 30, 2024 were $848 and $(133), respectively, and $1,010 and $8,987 during the three and six months ended June 30, 2023, respectively. Conditional Share Capital Plan In December 2023, the Company adopted the Conditional Share Capital Plan. Under the Conditional Share Capital Plan, the Company may at its discretion grant to plan participants, such as directors, certain employees and service providers, awards in the form of restricted shares and RSUs, share options, share appreciation rights, performance awards and other share-based awards. The Company has reserved 8,000,000 common shares for future issuance under this plan. As of June 30, 2024, the Company has 2,833,459 common shares available for the future issuance of share-based equity awards. As of June 30, 2024, the cumulative amount recorded as a net increase to additional paid-in capital within equity on the unaudited condensed consolidated balance sheet in respect of the Conditional Share Capital Plan was $2,357. The amounts of expense for all awards recognized for services received during the three and six months ended June 30, 2024 was $975 and $2,038, respectively. Inducement Plan In December 2023, the Company adopted the Inducement Plan. Under the Inducement Plan, the Company may at its discretion grant to any employee who is eligible to receive an employment inducement grant in accordance with NYSE Listed Company Manual 303A.08. The maximum number of common shares in respect of which awards may be granted under the Inducement Plan is 1,000,000 common shares (including share-based equity awards granted to date, less awards forfeited), subject to adjustment in the event of certain corporate transactions or events if necessary to prevent dilution or enlargement of the benefits made available under the plan. Equity incentive awards under the Inducement Plan may be granted in the form of options, share appreciation rights, restricted shares, restricted share units, performance awards or other share-based awards but not “incentive stock options” for purposes of U.S. tax laws. As of June 30, 2024, the Company has 688,800 common shares available for the future issuance of share-based equity awards under this plan. As of June 30, 2024, the cumulative amount recorded as a net increase to additional paid-in capital within equity on the unaudited condensed consolidated balance sheet in respect of the Inducement Plan was $95. The amounts of expense for all awards recognized for services received during the three and six months ended June 30, 2024 was $95 under this plan. Share Options Pursuant to the 2019 Equity Incentive Plan, the Conditional Share Capital Plan and Inducement Plan (the “Share-based Compensation Plans”), the Company may grant share options to its directors, certain employees and service providers working for the benefit of the Company at the time. The exercise price per share option is set by the Company at the fair market value of the underlying common shares on the date of grant, as determined by the Company, which is generally the closing share price of the Company’s common shares traded on the NYSE. The awards generally vest 25% on the first anniversary of the date of grant, and thereafter evenly on a monthly basis over the subsequent three years. The contractual term of each share option award granted is ten years. Under the grant, the options may be settled only in common shares of the Company. Therefore, the grants of share options under the 2019 Equity Incentive Plan and Inducement Plan have been accounted for as equity-settled under US GAAP. As such, the Company records a charge for the vested portion of award grants and for partially earned but non-vested portions of award grants. This results in a front-loaded charge to the Company’s unaudited condensed consolidated statements of operations and a corresponding increase to additional paid-in capital within equity on the unaudited condensed consolidated balance sheets. The expense (reversal) recognized for services received during the three and six months ended June 30, 2024 was $689 and $(745), respectively, and $(715) and $4,066 during the three and six months ended June 30, 2023, respectively. Movements in the number of awards outstanding under the Plans described above and their related weighted average strike prices are as follows: Weighted average strike price per share (in $ per share) Number of awards Weighted average remaining life in years Aggregate Intrinsic Value (in $ thousands) Outstanding as of December 31, 2023 $11.00 10,744,406 8.14 $ — Granted 3.83 540,400 Forfeited 10.50 (428,200) Expired 32.53 (866,595) Exercised 2.62 (31,988) Outstanding as of June 30, 2024 $9.23 9,958,023 7.77 $ — As of June 30, 2024, 4,910,379 awards are vested and exercisable out of the total outstanding awards of 9,958,023 common shares. As of June 30, 2024, the weighted average strike price and weighted average remaining life for vested and exercisable awards is $14.18 and 6.93 years, respectively. Awards outstanding as of June 30, 2024 have expiration dates through 2034. The weighted average grant date fair value of the awards granted during the six months ended June 30, 2024 was $3.02. The aggregate intrinsic value of vested and exercisable options was zero. As of June 30, 2024, the unrecognized compensation cost related to 5,047,644 unvested share options expected to vest was $9.8 million. This unrecognized cost will be recognized over an estimated weighted-average amortization period of 1.53 years. The fair values of the options granted under the 2019 Equity Incentive Plan and the Inducement Plan were determined on the date of the grant using the Black-Scholes option-pricing model. The Company used a third-party valuation firm to assist in calculating the fair value of the award grants per participant. The fair values of the options granted during the three and six months ended June 30, 2024 and 2023 were determined on the date of grant using the following assumptions: Three months ended June 30, Six months ended June 30, 2024 2023 2024 2023 Share price, in $ 3.31-4.71 1.96-2.38 1.69-4.86 1.96-5.45 Strike price, in $ 3.31-4.71 1.96-2.38 1.69-4.86 1.96-5.45 Expected volatility, in % 95 75-80 95 75-80 Award life, in years 6.08 6.08 6.08 6.08 Expected dividends — — — — Risk-free interest rate, in % 4.24-4.54 3.56-4.02 3.75-4.54 3.39-4.13 During the three and six months ended June 30, 2023, the expected volatility was based on the Company’s historical volatility and selected volatility determined by median values observed among other comparable public companies. Beginning in the third quarter of 2023, the Company’s expected volatility is no longer determined by values observed among other comparable companies and is now based on the Company’s historical volatility. The award life for options granted was based on the time interval between the date of grant and the date during the ten-year life after which, when making the grant, the Company expected on average that participants would exercise their options. RSUs Pursuant to the Share-based Compensation Plans, the Company may grant RSUs to its directors, certain employees and service providers working for the benefit of the Company at the time. The awards generally vest annually over a period of two June 30, 2024 is $1,229 and $2,745, respectively, and $1,725 and $4,921 during the three and six months ended June 30, 2023, respectively. The following table summarizes the RSU awards outstanding as of June 30, 2024: Number of awards Weighted average grant date fair value (in $ per share) December 31, 2023 6,533,843 $2.03 Granted 280,000 3.16 Vested (502,929) 9.17 Forfeited (521,038) 1.88 June 30, 2024 (1) 5,789,876 $1.48 (1) Includes 5,166,541 RSUs outstanding in connection with the Conditional Share Capital Pan. The total fair value of RSU awards vested (as measured on the date of vesting) during the six months ended June 30, 2024 was $2.1 million. Employee Stock Purchase Plan In June 2022, the Company adopted the 2022 Employee Stock Purchase Plan (“ESPP”), which allows eligible employees to purchase designated shares of the Company's common shares at a discount, over a series of offering periods through accumulated payroll deductions. The Company offers the ESPP to employees twice a year with each having a six-month offering period. The first offering period is generally from January 1st through June 30th and the second offering period is from July 1st through December 31st. The grant date is the first day of each offering period.

Loss per share

Loss per share	6 Months Ended
	Jun. 30, 2024
Earnings Per Share [Abstract]
Loss per share	Loss per share The basic loss per share is calculated by dividing the net loss attributable to shareholders by the weighted average number of shares and pre-funded warrants outstanding during the period, excluding common shares owned by the Company and held as treasury shares, as follows: Three months ended June 30, Six months ended June 30, (in thousands, except per share amounts) 2024 2023 2024 2023 Net loss $ (36,544) $ (48,922) $ (83,150) $ (108,296) Weighted average number of shares outstanding 95,691,245 81,471,127 89,121,783 81,140,287 Basic and diluted loss per share $ (0.38) $ (0.60) $ (0.93) $ (1.33) For the three and six months ended June 30, 2024 and 2023, basic and diluted loss per share is calculated on the weighted average number of shares issued and outstanding and excludes shares to be issued under the Equity Incentive Plan 2019, Conditional Share Capital Plan, Inducement Plan, the Company’s warrant agreements and 2022 ESPP as the effect of including those shares would be anti-dilutive. See note 9, “Senior secured term loan facility,” note 10, “Deerfield warrants”, note 14, “Shareholders’ equity”, and note 17, “Share-based compensation expense,” for further information. Potentially dilutive securities that were not included in the diluted per share calculations because the effect of including them would be anti-dilutive were as follows: Six months ended June 30, 2024 2023 2019 Equity Incentive Plan - Share Options 9,269,223 11,293,279 Inducement Plan - Share Options 688,800 — 2019 Equity Incentive Plan - RSUs 623,335 1,108,899 Conditional Share Capital Plan - RSUs 5,166,541 — Outstanding warrants 4,940,135 4,940,135 20,688,034 17,342,313

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Pay vs Performance Disclosure
Loss for the period	$ (36,544)	$ (48,922)	$ (83,150)	$ (108,296)

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Jun. 30, 2024
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2024
Accounting Policies [Abstract]
Basis of preparation and principles of consolidation	Basis of preparation and principles of consolidation These accompanying unaudited condensed consolidated financial statements, which include the accounts of the Company and its wholly-owned subsidiaries, have been prepared following the requirements of the U.S. Securities and Exchange Commission for interim reporting. As permitted under those rules, certain footnotes and other financial information that are normally required by U.S. generally accepted accounting principles, or U.S. GAAP, can be condensed or omitted. All intercompany transactions and balances have been eliminated in consolidation. The information included in this Quarterly Report on Form 10‑Q should be read in conjunction with our annual audited consolidated financial statements and accompanying notes included in the Company’s Annual Report on Form 10‑K for the year ended December 31, 2023. In the opinion of management, these condensed consolidated financial statements have been prepared on the same basis as the annual audited consolidated financial statements and include all adjustments, consisting only of normal recurring adjustments, considered necessary for the fair statement of our financial position and operating results. The results for the three and six months ended June 30, 2024 are not necessarily indicative of the results to be expected for the year ending December 31, 2024, for any other interim period or for any future period. The Company’s significant accounting policies have not changed substantially from those previously described in the Company’s Annual Report on Form 10‑K for the year ended December 31, 2023.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses, and related disclosures in the unaudited condensed consolidated financial statements and accompanying notes. Management bases its estimates on historical experience and on assumptions believed to be reasonable under the circumstances. Actual results could differ materially from those estimates.
Recent Accounting Pronouncements	Recent Accounting Pronouncements New accounting pronouncements which have been adopted There are no accounting pronouncements that the Company has recently adopted. Issued but not yet adopted In November 2023, the FASB amended guidance in ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. The revised guidance requires that a public entity disclose significant segment expenses regularly reviewed by the chief operating decision maker (CODM), including public entities with a single reportable segment. The amended guidance is effective for fiscal years beginning in January 2024 and interim periods beginning January 2025 on a retrospective basis. Early adoption is permitted. The Company is currently evaluating the effect that adoption of ASU 2023-07 will have on its consolidated financial statements. In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures. The ASU requires the annual financial statements to include consistent categories and greater disaggregation of information in the rate reconciliation, and income taxes paid disaggregated by jurisdiction. ASU 2023-09 is effective for the Company’s annual reporting periods beginning in January 2025. Adoption is either with a prospective method or a fully retrospective method of transition. Early adoption is permitted. The Company is currently evaluating the effect that adoption of ASU 2023-09 will have on its consolidated financial statements.

Fair value measurements (Tables

Fair value measurements (Tables)	6 Months Ended
	Jun. 30, 2024
Fair Value Disclosures [Abstract]
Schedule of Fair Value, Liabilities Measured on Recurring Basis	The Deerfield warrants, which are measured at fair value on a recurring basis, were as follows as of June 30, 2024 and December 31, 2023: (in thousands) Total Quoted prices in active markets for identical assets and liabilities (Level 1) Other observable inputs (Level 2) Significant unobservable inputs (Level 3) June 30, 2024: Deerfield warrant obligation $ 1,134 $ — $ 1,134 $ — Total $ 1,134 $ — $ 1,134 $ — (in thousands) Total Quoted prices in active markets for identical assets and liabilities (Level 1) Other observable inputs (Level 2) Significant unobservable inputs (Level 3) December 31, 2023: Deerfield warrant obligation $ 296 $ — $ 296 $ — Total $ 296 $ — $ 296 $ —

Inventory (Tables)

Inventory (Tables)	6 Months Ended
	Jun. 30, 2024
Inventory Disclosure [Abstract]
Schedule of Inventory	As of June 30, 2024 and December 31, 2023 inventory consisted of the following: (in thousands) June 30, 2024 December 31, 2023 Work in progress $ 15,123 $ 16,095 Finished goods 68 82 Total inventory, net $ 15,191 $ 16,177

Property and equipment (Tables)

Property and equipment (Tables)	6 Months Ended
	Jun. 30, 2024
Property, Plant and Equipment [Abstract]
Schedule of Property, Plant and Equipment	Property and equipment as of June 30, 2024 and December 31, 2023 consisted of the following: (in thousands) June 30, 2024 December 31, 2023 Leasehold improvements $ 3,905 $ 3,953 Laboratory equipment 4,154 3,652 Office equipment 977 1,119 Hardware and computer software 1,138 1,173 10,174 9,897 Less: accumulated depreciation (4,691) (4,275) Property and equipment, net $ 5,483 $ 5,622

Interest in joint venture (Tabl

Interest in joint venture (Tables)	6 Months Ended
	Jun. 30, 2024
Equity Method Investments and Joint Ventures [Abstract]
Schedule of Equity Method Investments	The table below provides a rollforward of the Company’s interest in Overland ADCT BioPharma as of June 30, 2024 and December 31, 2023. (in thousands) Interest in joint venture January 1, 2023 $ 7,613 Share of comprehensive loss in joint venture (5,966) December 31, 2023 $ 1,647 Share of comprehensive loss in joint venture (1,387) June 30, 2024 $ 260

Accrued expenses and other cu_2

Accrued expenses and other current liabilities (Tables)	6 Months Ended
	Jun. 30, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Accrued Expenses and Other Current Liabilities	Accrued expenses and other current liabilities consist of the following: (in thousands) June 30, 2024 December 31, 2023 Accrued R&D costs $ 18,304 $ 24,902 Accrued payroll and benefits 8,088 12,693 Gross-to-net sales adjustments, short-term 8,180 1,543 Operating lease liabilities, short-term 1,415 1,467 Other 10,937 11,496 $ 46,924 $ 52,101

Senior secured term loan faci_2

Senior secured term loan facility (Tables)	6 Months Ended
	Jun. 30, 2024
Debt Disclosure [Abstract]
Schedule of Long-Term Debt Instruments	The following table provides a summary of the interest expense for the Company’s senior secured term loan for the three months ended June 30, 2024 and 2023: Three months ended June 30, Six months ended June 30, 2024 2023 2024 2023 Contractual interest expense $ 3,973 $ 3,807 $ 7,873 $ 7,517 Amortization of debt discount 440 673 943 1,503 Total $ 4,413 $ 4,480 $ 8,816 $ 9,020
Schedule of Maturities of Long-Term Debt	Contractual payments due under our senior secured term loans, including exit fees are as follows (in thousands): 2024 (remainder) $ — 2025 — 2026 3,090 2027 9,330 2028 12,480 Thereafter 99,840 Total $ 124,740

Deerfield warrants (Tables)

Deerfield warrants (Tables)	6 Months Ended
	Jun. 30, 2024
Other Liabilities Disclosure [Abstract]
Schedule of Fair Value Measurement Inputs and Valuation Techniques	Key inputs for the valuation of the warrant obligation as of June 30, 2024 and December 31, 2023 were as follows: As of As of June 30, 2024 December 31, 2023 Exercise price in $ 24.70 and 28.07 24.70 and 28.07 Share price in $ 3.16 1.66 Risk-free interest rate 5.1 % 4.6 % Expected volatility 140.6 % 116.0 % Expected term (months) 10.7 months 16.7 months Dividend yield — — Black-Scholes value in $ 0.27 and 0.23 0.07 and 0.06

Deferred royalty obligation (Ta

Deferred royalty obligation (Tables)	6 Months Ended
	Jun. 30, 2024
Other Liabilities Disclosure [Abstract]
Schedule of Royalty Purchase Obligation	The table below provides a rollforward of the Company’s debt obligation relating to the royalty purchase agreement. (in thousands) Liability balance at January 1, 2023 $ 222,277 Plus: Additional proceeds from the sale of future royalties 75,000 Less: Transaction costs 1,898 Less: royalty payments 8,709 Plus: interest expense 27,915 Less: cumulative catch-up adjustment, Other, net 4,972 Liability balance at December 31, 2023 309,613 Less: royalty payments 2,569 Plus: interest expense 16,359 Less: cumulative catch-up adjustment, Other, net 526 Liability balance at June 30, 2024 $ 322,877

Pension and post-retirement b_2

Pension and post-retirement benefit obligations (Tables)	6 Months Ended
	Jun. 30, 2024
Retirement Benefits [Abstract]
Schedule of Net Benefit Costs	The net periodic benefit cost for the three and six months ended June 30, 2024 and 2023 is as follows: Three months ended June 30, Six months ended June 30, (in thousands) 2024 2023 2024 2023 Net periodic benefit cost: Service cost $ 183 $ 275 $ 347 $ 447 Interest cost 37 75 75 149 Expected return on plan assets (59) (83) (118) (165) Amortization of prior service cost (40) (40) (81) (79) Net periodic benefit cost $ 121 $ 227 $ 223 $ 352

Revenue (Tables)

Revenue (Tables)	6 Months Ended
	Jun. 30, 2024
Revenue from Contract with Customer [Abstract]
Schedule of Disaggregation of Revenue	The table below provides a disaggregation of revenues by type and customer location for the three and six months ended June 30, 2024 and 2023: Three months ended June 30, Six months ended June 30, (in thousands) 2024 2023 2024 2023 Types of goods and services Product revenue, net $ 17,030 $ 19,197 $ 34,878 $ 38,150 Royalties 380 86 585 125 Total revenue $ 17,410 $ 19,283 $ 35,463 $ 38,275 Customer Location U.S. $ 17,030 $ 19,197 $ 34,878 $ 38,150 EMEA (1) 380 86 585 125 Total revenue $ 17,410 $ 19,283 $ 35,463 $ 38,275 (1) Europe, the Middle East and Africa The table below provides a rollforward of the Company’s accruals related to the GTN sales adjustments for the three and six months ended June 30, 2024: (in thousands) Discarded Drug Rebate Other Adjustments Total Balance as of April 1, 2024 $ 9,393 $ 3,768 $ 13,161 GTN accruals for current period 1,858 3,759 5,617 Prior period adjustments — (791) (791) Credits, payments and reclassifications — (3,479) (3,479) Balance as of June 30, 2024 $ 11,251 $ 3,257 $ 14,508 Balance as of January 1, 2024 $ 7,391 $ 3,946 $ 11,337 GTN accruals for current period 3,904 8,217 12,121 Prior period adjustments (44) (1,020) (1,064) Credits, payments and reclassifications — (7,886) (7,886) Balance as of June 30, 2024 $ 11,251 $ 3,257 $ 14,508 The table below provides a rollforward of the Company’s accruals related to the GTN sales adjustments for the three and six months ended June 30, 2023: (in thousands) Discarded Drug Rebate Other Adjustments Total Balance as of April 1, 2023 $ 1,316 $ 3,046 $ 4,362 GTN accruals for current period 1,485 4,298 5,783 Prior period adjustments — (229) (229) Credits, payments and reclassifications — (4,182) (4,182) Balance as of June 30, 2023 $ 2,801 $ 2,933 $ 5,734 Balance as of January 1, 2023 $ — $ 3,746 $ 3,746 GTN accruals for current period 2,801 8,598 11,399 Prior period adjustments — (877) (877) Credits, payments and reclassifications — (8,534) (8,534) Balance as of June 30, 2023 $ 2,801 $ 2,933 $ 5,734 The table below provides the classification of the accruals related to the GTN sales adjustment included in the Company’s unaudited condensed consolidated balance sheets as of June 30, 2024 and December 31, 2023. (in thousands) June 30, 2024 December 31, 2023 Accounts receivable, net $ 2,424 $ 2,403 Other current and non-current liabilities 12,084 8,934 $ 14,508 $ 11,337
Schedule of Product Revenue by Customer	Customers from which we derive more than 10% of our total product revenues for the three and six months ended June 30, 2024 and 2023 are as follows: Three months ended June 30, Six months ended June 30, 2024 2023 2024 2023 McKesson 37 % 38 % 40 % 38 % AmerisourceBergen Corporation 35 % 37 % 36 % 37 % Cardinal Health 28 % 25 % 24 % 25 %

Other income (expense) (Tables)

Other income (expense) (Tables)	6 Months Ended
	Jun. 30, 2024
Other Income and Expenses [Abstract]
Schedule of Interest Expense	The components of Interest expense for the three and six months ended June 30, 2024 and 2023 are as follows: Three months ended June 30, Six months ended June 30, (in thousands) 2024 2023 2024 2023 Deferred royalty obligation interest expense $ 8,266 $ 5,829 $ 16,359 $ 11,575 Effective interest expense on senior secured term loan facility 4,413 4,480 8,816 9,020 Other interest expense — — — 5 Interest expense $ 12,679 $ 10,309 $ 25,175 $ 20,600
Schedule of Other, Net	The components of Other, net for the three and six months ended June 30, 2024 and 2023 are as follows: Three months ended June 30, Six months ended June 30, (in thousands) 2024 2023 2024 2023 Deerfield warrant obligation, change in fair value income (expense) $ 2,230 $ 20 $ (838) $ 636 Cumulative catch-up adjustment income (expense), deferred royalty obligation 263 (5,417) 526 (5,288) Exchange differences (loss) gain (59) 15 (96) (37) R&D tax credit 320 315 567 455 Other, net $ 2,754 $ (5,067) $ 159 $ (4,234)

Share-based compensation (Table

Share-based compensation (Tables)	6 Months Ended
	Jun. 30, 2024
Share-Based Payment Arrangement [Abstract]
Schedule of Share-Based Payment Arrangement, Option, Activity	Movements in the number of awards outstanding under the Plans described above and their related weighted average strike prices are as follows: Weighted average strike price per share (in $ per share) Number of awards Weighted average remaining life in years Aggregate Intrinsic Value (in $ thousands) Outstanding as of December 31, 2023 $11.00 10,744,406 8.14 $ — Granted 3.83 540,400 Forfeited 10.50 (428,200) Expired 32.53 (866,595) Exercised 2.62 (31,988) Outstanding as of June 30, 2024 $9.23 9,958,023 7.77 $ —
Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions	The fair values of the options granted during the three and six months ended June 30, 2024 and 2023 were determined on the date of grant using the following assumptions: Three months ended June 30, Six months ended June 30, 2024 2023 2024 2023 Share price, in $ 3.31-4.71 1.96-2.38 1.69-4.86 1.96-5.45 Strike price, in $ 3.31-4.71 1.96-2.38 1.69-4.86 1.96-5.45 Expected volatility, in % 95 75-80 95 75-80 Award life, in years 6.08 6.08 6.08 6.08 Expected dividends — — — — Risk-free interest rate, in % 4.24-4.54 3.56-4.02 3.75-4.54 3.39-4.13
Schedule of Share-Based Payment Arrangement, Restricted Stock Unit, Activity	The following table summarizes the RSU awards outstanding as of June 30, 2024: Number of awards Weighted average grant date fair value (in $ per share) December 31, 2023 6,533,843 $2.03 Granted 280,000 3.16 Vested (502,929) 9.17 Forfeited (521,038) 1.88 June 30, 2024 (1) 5,789,876 $1.48 (1) Includes 5,166,541 RSUs outstanding in connection with the Conditional Share Capital Pan.

Loss per share (Tables)

Loss per share (Tables)	6 Months Ended
	Jun. 30, 2024
Earnings Per Share [Abstract]
Schedule of Loss per Share	The basic loss per share is calculated by dividing the net loss attributable to shareholders by the weighted average number of shares and pre-funded warrants outstanding during the period, excluding common shares owned by the Company and held as treasury shares, as follows: Three months ended June 30, Six months ended June 30, (in thousands, except per share amounts) 2024 2023 2024 2023 Net loss $ (36,544) $ (48,922) $ (83,150) $ (108,296) Weighted average number of shares outstanding 95,691,245 81,471,127 89,121,783 81,140,287 Basic and diluted loss per share $ (0.38) $ (0.60) $ (0.93) $ (1.33)
Schedule of Potentially Dilutive Securities Excluded from Earnings Per Share Calculation	Potentially dilutive securities that were not included in the diluted per share calculations because the effect of including them would be anti-dilutive were as follows: Six months ended June 30, 2024 2023 2019 Equity Incentive Plan - Share Options 9,269,223 11,293,279 Inducement Plan - Share Options 688,800 — 2019 Equity Incentive Plan - RSUs 623,335 1,108,899 Conditional Share Capital Plan - RSUs 5,166,541 — Outstanding warrants 4,940,135 4,940,135 20,688,034 17,342,313

Description of Business and O_2

Description of Business and Organization (Details)	6 Months Ended
	Jun. 30, 2024 subsidiary
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of subsidiaries	3

Summary of Significant Accoun_3

Summary of Significant Accounting Policies - Narrative (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2024 USD ($) segment	Dec. 31, 2023 USD ($)
Accounting Policies [Abstract]
Number of business segments	1
Number of operating segments	1
Cash and cash equivalents | $	$ 300,119	$ 278,598

Fair value measurements (Detail

Fair value measurements (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deerfield warrant obligation	$ 1,134	$ 296
Total	1,134	296
Quoted prices in active markets for identical assets and liabilities (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deerfield warrant obligation	0	0
Total	0	0
Other observable inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deerfield warrant obligation	1,134	296
Total	1,134	296
Significant unobservable inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deerfield warrant obligation	0	0
Total	$ 0	$ 0

Inventory - Schedule of Invento

Inventory - Schedule of Inventory (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Inventory Disclosure [Abstract]
Work in progress	$ 15,123	$ 16,095
Finished goods	68	82
Inventory	$ 15,191	$ 16,177

Inventory - Narrative (Details)

Inventory - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Inventory Disclosure [Abstract]
Write-downs of inventory	$ 288	$ 727	$ 1,036	$ 780

Property and equipment - Schedu

Property and equipment - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Property, Plant and Equipment [Line Items]
Property and equipment	$ 10,174	$ 9,897
Less: accumulated depreciation	(4,691)	(4,275)
Property and equipment, net	5,483	5,622
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment	3,905	3,953
Laboratory equipment
Property, Plant and Equipment [Line Items]
Property and equipment	4,154	3,652
Office equipment
Property, Plant and Equipment [Line Items]
Property and equipment	977	1,119
Hardware and computer software
Property, Plant and Equipment [Line Items]
Property and equipment	$ 1,138	$ 1,173

Property and equipment - Narrat

Property and equipment - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Property, Plant and Equipment [Abstract]
Depreciation	$ 326	$ 273	$ 657	$ 536

Interest in joint venture - Nar

Interest in joint venture - Narrative (Details)	6 Months Ended
	Jun. 30, 2024 subsidiary
Equity Method Investments and Joint Ventures [Abstract]
Number of product candidates developed and commercialized in joint venture	3

Interest in joint venture - Sch

Interest in joint venture - Schedule of Joint Venture Investment (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Interest in joint venture
Beginning balance			$ 1,647
Share of comprehensive loss in joint venture	$ (597)	$ (767)	(1,284)	$ (2,130)
Ending balance	260		260		$ 1,647
Overland ADCT BioPharma (CY) Limited
Interest in joint venture
Beginning balance			1,647	$ 7,613	7,613
Share of comprehensive loss in joint venture			(1,387)		(5,966)
Ending balance	$ 260		$ 260		$ 1,647

Income taxes (Details)

Income taxes (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Income Tax Disclosure [Abstract]
Income tax (expense) benefit	$ 234	$ (4,498)	$ 397	$ (3,980)
Loss before income taxes	$ 35,713	$ 52,653	$ 81,469	$ 110,146

Accrued expenses and other cu_3

Accrued expenses and other current liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accrued R&D costs	$ 18,304	$ 24,902
Accrued payroll and benefits	8,088	12,693
Gross-to-net sales adjustments, short-term	8,180	1,543
Operating lease liabilities, short-term	1,415	1,467
Other	10,937	11,496
Accrued expenses and other current liabilities	$ 46,924	$ 52,101

Senior secured term loan faci_3

Senior secured term loan facility - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		6 Months Ended
	Aug. 15, 2022	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	May 31, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Warrant exercise price (in dollars per share)						$ 0.08
Issuance of shares (in shares)	733,568
Senior secured term loans		$ 113,673		$ 113,673			$ 112,730
Loan Agreement Warrants
Debt Instrument [Line Items]
Securities called by warrant (in shares)	527,295
Warrant exercise price (in dollars per share)	$ 8.30
Loan Agreement
Debt Instrument [Line Items]
Interest expense on debt		4,413	$ 4,480	8,816	$ 9,020
Line of Credit | Loan Agreement | Secured Debt
Debt Instrument [Line Items]
Face amount	$ 175,000
Long-term debt	$ 120,000
Interest expense on debt		$ 4,413	$ 4,480	$ 8,816	$ 9,020
Debt effective interest rate		16.83%		16.83%

Senior secured term loan faci_4

Senior secured term loan facility - Schedule of Interest Expense (Details) - Loan Agreement - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Debt Instrument [Line Items]
Total	$ 4,413	$ 4,480	$ 8,816	$ 9,020
Line of Credit | Secured Debt
Debt Instrument [Line Items]
Contractual interest expense	3,973	3,807	7,873	7,517
Amortization of debt discount	440	673	943	1,503
Total	$ 4,413	$ 4,480	$ 8,816	$ 9,020

Senior secured term loan faci_5

Senior secured term loan facility - Schedule of Maturities (Details) - Loan Agreement $ in Thousands	Jun. 30, 2024 USD ($)
Debt Instrument [Line Items]
2024 (remainder)	$ 0
2025	0
2026	3,090
2027	9,330
2028	12,480
Thereafter	99,840
Total	$ 124,740

Deerfield warrants - Narrative

Deerfield warrants - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		6 Months Ended
	Aug. 15, 2022	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	May 31, 2024	Dec. 31, 2023
Class of Warrant or Right [Line Items]
Warrant exercise price (in dollars per share)						$ 0.08
Deerfield warrant obligation, change in fair value income (expense)				$ (838)	$ 636
Deerfield warrant obligation		$ 1,134		1,134			$ 296
Deerfield Warrants
Class of Warrant or Right [Line Items]
Debt conversion, warrants issued (in shares)	4,412,840
Deerfield warrant obligation, change in fair value income (expense)		2,230	$ 20	(838)	$ 636
Deerfield warrant obligation		$ 1,134		$ 1,134			$ 296
Warrants, Tranche One | Deerfield Warrants
Class of Warrant or Right [Line Items]
Debt conversion, warrants issued (in shares)	2,631,578
Warrant exercise price (in dollars per share)	$ 24.70
Warrants, Tranche Two | Deerfield Warrants
Class of Warrant or Right [Line Items]
Debt conversion, warrants issued (in shares)	1,781,262
Warrant exercise price (in dollars per share)	$ 28.07

Deerfield warrants - Schedule o

Deerfield warrants - Schedule of Fair Value Inputs (Details) - Deerfield Warrants	Jun. 30, 2024 $ / shares	Dec. 31, 2023 $ / shares
Share price in $
Class of Warrant or Right [Line Items]
Warrants, measurement input	3.16	1.66
Risk-free interest rate
Class of Warrant or Right [Line Items]
Warrants, measurement input	0.051	0.046
Expected volatility
Class of Warrant or Right [Line Items]
Warrants, measurement input	1.406	1.160
Expected term (months)
Class of Warrant or Right [Line Items]
Warrants, term	10 months 21 days	16 months 21 days
Dividend yield
Class of Warrant or Right [Line Items]
Warrants, measurement input	0	0
Minimum | Exercise price in $
Class of Warrant or Right [Line Items]
Warrants, measurement input	24.70	24.70
Minimum | Black-Scholes value in $
Class of Warrant or Right [Line Items]
Warrants, measurement input	0.27	0.07
Maximum | Exercise price in $
Class of Warrant or Right [Line Items]
Warrants, measurement input	28.07	28.07
Maximum | Black-Scholes value in $
Class of Warrant or Right [Line Items]
Warrants, measurement input	0.23	0.06

Deferred royalty obligation - N

Deferred royalty obligation - Narrative (Details) - USD ($) $ in Millions		12 Months Ended
	Aug. 25, 2021	Dec. 31, 2023
Other Liabilities Disclosure [Abstract]
Royalty purchase agreement	$ 325
Proceeds from royalties	$ 225	$ 75

Deferred royalty obligation - S

Deferred royalty obligation - Schedule of Royalty Obligation (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2024	Dec. 31, 2023
Deferred Royalty Obligation [Roll Forward]
Beginning balance	$ 309,613	$ 222,277
Plus: Additional proceeds from the sale of future royalties		75,000
Less: Transaction costs		1,898
Less: royalty payments	2,569	8,709
Plus: interest expense	16,359	27,915
Less: cumulative catch-up adjustment, Other, net	526	4,972
Ending balance	$ 322,877	$ 309,613

Pension and post-retirement b_3

Pension and post-retirement benefit obligations - Narrative (Details)	6 Months Ended
	Jun. 30, 2024
Retirement Benefits [Abstract]
Capital and interest guarantee	100%

Pension and post-retirement b_4

Pension and post-retirement benefit obligations - Schedule of Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Retirement Benefits [Abstract]
Service cost	$ 183	$ 275	$ 347	$ 447
Interest cost	37	75	75	149
Expected return on plan assets	(59)	(83)	(118)	(165)
Amortization of prior service cost	(40)	(40)	(81)	(79)
Net periodic benefit cost	$ 121	$ 227	$ 223	$ 352

Shareholders' equity (Details)

Shareholders' equity (Details) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended	6 Months Ended
	May 31, 2024 USD ($) $ / shares shares	Jun. 30, 2024 USD ($)	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)
Subsidiary, Sale of Stock [Line Items]
Warrant exercise price (in dollars per share) | $ / shares	$ 0.08
Proceeds from common shares, 2024 Equity Offering, net of transaction costs			$ 61,731	$ 0
Issuance of warrants, underwritten offering, net of transaction costs		$ 36,925	$ 36,925
2024 Pre-Funded warrant
Subsidiary, Sale of Stock [Line Items]
Class of warrent or right, exchange term (in days)	90 days
Class of warrant or right, outstanding (in shares) | shares	50,000
Beneficial ownership maximum term (in days)	61 days
2024 Pre-Funded warrant | Minimum
Subsidiary, Sale of Stock [Line Items]
Beneficial ownership (as a percent)	0.0999
2024 Pre-Funded warrant | Maximum
Subsidiary, Sale of Stock [Line Items]
Beneficial ownership (as a percent)	0.1999
2024 Equity Offering
Subsidiary, Sale of Stock [Line Items]
Sale of stock, issued (in shares) | shares	13,411,912
Sale of stock, price (in dollars per share) | $ / shares	$ 4.81
Sale of stock, amount	$ 105,000
Sale of stock, transaction costs	7,600
Proceeds from common shares, 2024 Equity Offering, net of transaction costs	97,400
Additional paid in capital	60,500
Issuance of warrants, underwritten offering, net of transaction costs	$ 36,900
2024 Equity Offering | Common Stock
Subsidiary, Sale of Stock [Line Items]
Sale of stock, price (in dollars per share) | $ / shares	$ 4.90
2024 Equity Offering | 2024 Pre-Funded warrant
Subsidiary, Sale of Stock [Line Items]
Sale of stock, issued (in shares) | shares	8,163,265

Revenue - Schedule of Disaggreg

Revenue - Schedule of Disaggregation of Revenues (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Disaggregation of Revenue [Line Items]
Revenues	$ 17,410	$ 19,283	$ 35,463	$ 38,275
U.S.
Disaggregation of Revenue [Line Items]
Revenues	17,030	19,197	34,878	38,150
EMEA
Disaggregation of Revenue [Line Items]
Revenues	380	86	585	125
Product revenue, net
Disaggregation of Revenue [Line Items]
Revenues	17,030	19,197	34,878	38,150
Royalties
Disaggregation of Revenue [Line Items]
Revenues	$ 380	$ 86	$ 585	$ 125

Revenue - Schedule of GTN Produ

Revenue - Schedule of GTN Product Revenue, Net (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Gross To Net Sales Adjustment Rollforward [Roll Forward]
Balance as of April 1, 2024	$ 13,161	$ 4,362	$ 11,337	$ 3,746
GTN accruals for current period	5,617	5,783	12,121	11,399
Prior period adjustments	(791)	(229)	(1,064)	(877)
Credits, payments and reclassifications	(3,479)	(4,182)	(7,886)	(8,534)
Balance as of June 30, 2024	14,508	5,734	14,508	5,734
Gross To Net Sales Adjustment [Abstract]
Accounts receivable, net	2,424		2,424		$ 2,403
Other current and non-current liabilities	12,084		12,084		8,934
Gross to net sales adjustment	14,508	5,734	14,508	5,734	11,337
Discarded Drug Rebate
Gross To Net Sales Adjustment Rollforward [Roll Forward]
Balance as of April 1, 2024	9,393	1,316	7,391	0
GTN accruals for current period	1,858	1,485	3,904	2,801
Prior period adjustments	0	0	(44)	0
Credits, payments and reclassifications	0	0	0	0
Balance as of June 30, 2024	11,251	2,801	11,251	2,801
Gross To Net Sales Adjustment [Abstract]
Gross to net sales adjustment	11,251	2,801	11,251	2,801	7,391
Other Adjustments
Gross To Net Sales Adjustment Rollforward [Roll Forward]
Balance as of April 1, 2024	3,768	3,046	3,946	3,746
GTN accruals for current period	3,759	4,298	8,217	8,598
Prior period adjustments	(791)	(229)	(1,020)	(877)
Credits, payments and reclassifications	(3,479)	(4,182)	(7,886)	(8,534)
Balance as of June 30, 2024	3,257	2,933	3,257	2,933
Gross To Net Sales Adjustment [Abstract]
Gross to net sales adjustment	$ 3,257	$ 2,933	$ 3,257	$ 2,933	$ 3,946

Revenue - Schedule of Concentra

Revenue - Schedule of Concentration Risk by Customer (Details) - Revenue Benchmark - Customer Concentration Risk	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
McKesson
Disaggregation of Revenue [Line Items]
Concentration risk percentage	37%	38%	40%	38%
AmerisourceBergen Corporation
Disaggregation of Revenue [Line Items]
Concentration risk percentage	35%	37%	36%	37%
Cardinal Health
Disaggregation of Revenue [Line Items]
Concentration risk percentage	28%	25%	24%	25%

Other income (expense) - Narrat

Other income (expense) - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Other Income and Expenses [Abstract]
Interest income	$ 3.3	$ 2.4	$ 6.2	$ 4.5

Other income (expense) - Schedu

Other income (expense) - Schedule of Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Debt Instrument [Line Items]
Deferred royalty obligation interest expense	$ 8,266	$ 5,829	$ 16,359	$ 11,575
Other interest expense	0	0	0	5
Interest expense	12,679	10,309	25,175	20,600
Loan Agreement
Debt Instrument [Line Items]
Effective interest expense on senior secured term loan facility	$ 4,413	$ 4,480	$ 8,816	$ 9,020

Other income (expense) - Sche_2

Other income (expense) - Schedule of Other, Net (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Debt Instrument [Line Items]
Deerfield warrant obligation, change in fair value income (expense)			$ 838	$ (636)
Cumulative catch-up adjustment income (expense), deferred royalty obligation	$ 263	$ (5,417)	526	(5,288)
Exchange differences (loss) gain	(59)	15	(96)	(37)
R&D tax credit	320	315	567	455
Other, net	2,754	(5,067)	159	(4,234)
Deerfield Warrants
Debt Instrument [Line Items]
Deerfield warrant obligation, change in fair value income (expense)	$ (2,230)	$ (20)	$ 838	$ (636)

Share-based compensation - Narr

Share-based compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended		3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2022	Nov. 30, 2019	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense			$ 1,988	$ 1,118	$ 2,146	$ 9,192
Awards vested and exercisable (in shares)			4,910,379		4,910,379
Outstanding (in shares)			9,958,023		9,958,023		10,744,406
Weighted average strike price (in dollars per share)			$ 14.18		$ 14.18
Weighted average remaining life					6 years 11 months 4 days
Weighted average grant date fair value (in dollars per share)			$ 3.02		$ 3.02
Nonvested (in shares)			5,047,644		5,047,644
Unrecognized compensation costs			$ 9,800		$ 9,800
Share Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expense recognized			689	(715)	$ (745)	4,066
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage		25%
Vesting period		3 years
Award life for options granted		10 years
Unrecognized share-based compensation cost, period of recognition					1 year 6 months 10 days
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of shares vested					$ 2,100
2019 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares reserved for future issuance (in shares)		17,741,355
Share-based compensation expense					157,773		$ 157,906
Expense recognized			$ 848	1,010	$ (133)	8,987
2019 Equity Incentive Plan | Share Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares reserved for future issuance (in shares)			4,806,185		4,806,185
2019 Equity Incentive Plan | Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expense recognized			$ 1,229	1,725	$ 2,745	4,921
2019 Equity Incentive Plan | Restricted Stock Units | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		2 years
2019 Equity Incentive Plan | Restricted Stock Units | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Conditional Share Capital Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares reserved for future issuance (in shares)			2,833,459		2,833,459		8,000,000
Share-based compensation expense					$ 2,357
Expense recognized			$ 975		$ 2,038
Inducement Plan - Share Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares reserved for future issuance (in shares)			688,800		688,800
Share-based compensation expense					$ 95
Expense recognized			$ 95		95
Maximum shares available for grant (in shares)							1,000,000
2022 ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expense recognized			$ 70	$ 108	$ 146	$ 205
2022 ESPP | Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Offering period	6 months

Share-based compensation - Sche

Share-based compensation - Schedule of Option Activity (Details) - $ / shares	6 Months Ended	12 Months Ended
	Jun. 30, 2024	Dec. 31, 2023
Weighted average strike price per share (in $ per share)
Beginning balance (in dollars per share)	$ 11
Granted (in dollars per share)	3.83
Forfeited (in dollars per share)	10.50
Expired (in dollars per share)	32.53
Exercised (in dollars per share)	2.62
Ending balance (in dollars per share)	$ 9.23	$ 11
Number of awards
Beginning balance (in shares)	10,744,406
Granted (in shares)	540,400
Forfeited (in shares)	(428,200)
Expired (in shares)	(866,595)
Exercised (in shares)	(31,988)
Ending balance (in shares)	9,958,023	10,744,406
Additional Disclosures
Weighted average remaining life in years	7 years 9 months 7 days	8 years 1 month 20 days

Share-based compensation - Sc_2

Share-based compensation - Schedule of Stock Option Valuation Assumptions (Details) - $ / shares	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Strike price (in dollars per share)			$ 3.83
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility, in %	95%		95%
Award life, in years	6 years 29 days	6 years 29 days	6 years 29 days	6 years 29 days
Expected dividends	0%	0%	0%	0%
Risk-free interest rate, in %, minimum	4.24%	3.56%	3.75%	3.39%
Risk-free interest rate, in %, maximum	4.54%	4.02%	4.54%	4.13%
Employee Stock Option | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share price (in dollars per share)	$ 3.31	$ 1.96	$ 1.69	$ 1.96
Strike price (in dollars per share)	3.31	$ 1.96	1.69	$ 1.96
Expected volatility, in %		75%		75%
Employee Stock Option | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share price (in dollars per share)	4.71	$ 2.38	4.86	$ 5.45
Strike price (in dollars per share)	$ 4.71	$ 2.38	$ 4.86	$ 5.45
Expected volatility, in %		80%		80%

Share-based compensation - Sc_3

Share-based compensation - Schedule of RSU Activity (Details) - Restricted Stock Units	6 Months Ended
	Jun. 30, 2024 $ / shares shares
Number of awards
Beginning balance (in shares)	6,533,843
Granted (in shares)	280,000
Vested (in shares)	(502,929)
Forfeited (in shares)	(521,038)
Ending balance (in shares)	5,789,876
Weighted average grant date fair value
Beginning balance (in dollars per share) | $ / shares	$ 2.03
Granted (in dollars per share) | $ / shares	3.16
Vested (in dollars per share) | $ / shares	9.17
Forfeited (in dollars per share) | $ / shares	1.88
Ending balance (in dollars per share) | $ / shares	$ 1.48
Conditional Share Capital Plan - RSUs
Number of awards
Ending balance (in shares)	5,166,541

Loss per share - Schedule of Lo

Loss per share - Schedule of Loss per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Earnings Per Share [Abstract]
Net loss	$ (36,544)	$ (48,922)	$ (83,150)	$ (108,296)
Weighted average number of shares outstanding, diluted (in shares)	95,691,245	81,471,127	89,121,783	81,140,287
Weighted average number of shares outstanding, basic (in shares)	95,691,245	81,471,127	89,121,783	81,140,287
Net loss per share, diluted (in dollars per share)	$ (0.38)	$ (0.60)	$ (0.93)	$ (1.33)
Net loss per share, basic (in dollars per share)	$ (0.38)	$ (0.60)	$ (0.93)	$ (1.33)

Loss per share - Schedule of Po

Loss per share - Schedule of Potentially Dilutive Securities Excluded from Earnings Per Share Calculation (Details) - shares	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	20,688,034	17,342,313
2019 Equity Incentive Plan | Employee Stock Option
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	9,269,223	11,293,279
2019 Equity Incentive Plan | Restricted Stock Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	623,335	1,108,899
Inducement Plan - Share Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	688,800	0
Conditional Share Capital Plan - RSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	5,166,541	0
Outstanding warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	4,940,135	4,940,135