Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2022

Accounting Policies [Abstract]

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 consolidated balance sheet that sum to the total of the amounts reported in the consolidated statement of cash flows (in thousands):

	As of December 31,
	2022		2021
Cash and cash equivalents	$	68,424	$	55,912
Restricted cash		4,215		4,266
Total cash, cash equivalents and restricted cash shown in the statement of cash flows	$	72,639	$	60,178

Schedule of Estimated Useful Lives of Property and Equipment

Property and equipment are recorded at cost and depreciated or amortized using the straight-line method over the following estimated useful lives.

Asset Type:	Estimated useful life
Lab equipment	5-10 years
Leasehold improvements	Shorter of lease term or estimated useful life
Furniture and fixtures	4 years
Office and computer equipment	3-5 years

Schedule of Changes in Loss Provision

The following table below outlines the changes to the Strimvelis loss provision for the periods ended December 31, 2022 and 2021 (in thousands):

	Year Ended December 31,
	2022			2021
Balance at beginning of period	$	3,419		$	4,482
Amortization of loss provision		(274	)		(1,037	)
Foreign currency translation		(326	)		(26	)
Balance at end of period	$	2,819		$	3,419

Summary of Amounts Recognized to Offset Research and Development Expense

The following table outlines the changes to the research and development tax credit receivable, including amount recognized as an offset to research and development expense during the years ended December 31, 2022 and 2021 (in thousands):

	Year Ended December 31,
	2022			2021
Balance at beginning of period	$	30,723		$	17,344
Recognition of credit claims as offset to research and development expense		8,243			13,920
Receipt of credit claims		(30,811	)		-
Foreign currency translation		(2,213	)		(541	)
Balance at end of period	$	5,942		$	30,723

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 December 31,
	2022		2021
Share options		13,076,959		14,042,781
Unvested restricted incentive shares		2,253,199		512,908
		15,330,158		14,555,689