Basis of Presentation and Summary of Significant Accounting Policies (Tables)

6 Months Ended

Jun. 30, 2022

Accounting Policies [Abstract]

Summary of Amounts Recognized to Offset Research and Development Expense

The following table below outlines the changes to the research and development tax credit receivable, including amounts recognized as an offset to research and development expense during the periods. (amounts in thousands):

	Three Months Ended June 30,					Six Months Ended June 30,
	2022			2021		2022			2021
Balance at beginning of period	$	16,649		$	21,044	$	30,723		$	17,344
Recognition of credit claims as offset to research and    development expense		1,764			4,246		5,101			7,800
Receipt of credit claims		(1,916	)		—		(18,390	)		—
Foreign currency translation		(1,321	)		81		(2,258	)		227
Balance at end of period	$	15,176		$	25,371	$	15,176		$	25,371

Schedule of Reconciliation of Cash, Cash Equivalents and Restricted Cash

The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported in the condensed consolidated balance sheets that sum to the total of the amounts reported in the unaudited condensed consolidated statement of cash flows (amounts in thousands):

	June 30,		December 31,
	2022		2021
Cash and cash equivalents	$	53,470	$	55,912
Restricted cash		4,266		4,266
Total cash, cash equivalents and restricted cash shown in the statement of cash flows	$	57,736	$	60,178

Schedule of Changes in Loss Provision

The following table below outlines the changes to the Strimvelis loss provision for the three and six months ended June 30, 2022 and 2021 (amounts in thousands):

	Three Months Ended June 30,						Six Months Ended June 30,
	2022			2021			2022			2021
Balance at beginning of period	$	3,057		$	4,076		$	3,419		$	4,482
Amortization of loss provision		—			(368	)		(276	)		(814	)
Foreign currency translation		(230	)		28			(316	)		68
Balance at end of period	$	2,827		$	3,736		$	2,827		$	3,736

Disaggregated Product Revenue

The Company disaggregates revenue from contracts with customers by product type as it believes this presentation best depicts how the nature, amount, timing and uncertainty of the Company's revenue and cash flows are affected by economic factors, as shown below (in thousands):

	Three Months Ended June 30,				Six Months Ended June 30,
	2022		2021		2022		2021
Libmeldy	$	3,145	$	—	$	8,204	$	—
Strimvelis		636		—		636		—
	$	3,781	$	—	$	8,840	$	—

Securities Excluded in the Computation of Diluted Net Loss Per Ordinary Share

The following securities, presented based on amounts outstanding at each period end, are considered to be ordinary share equivalents, but were not included in the computation of diluted net loss per ordinary share because to do so would have been anti-dilutive:

	As of June 30,
	2022		2021
Share options		13,894,428		12,625,435
Unvested performance-based restricted share units		500,989		692,668
		14,395,417		13,318,103