Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Current assets:
Cash and cash equivalents	$ 721,451	$ 879,520
Prepaid expenses and other current assets	22,058	13,432
Research and development incentives receivable	60,753	35,653
Total current assets	804,262	928,605
Property and equipment, net	8,307	9,516
Operating lease right-of-use assets	5,806	7,673
Other assets	13,809	11,074
Total assets	832,184	956,868
Current liabilities:
Accounts payable	18,263	15,793
Accrued expenses and other current liabilities	44,538	41,246
Deferred revenue, current portion	14,621	10,191
Total current liabilities	77,422	67,230
Operating lease liabilities, net of current portion	1,765	3,990
Deferred revenue, net of current portion	82,943	91,467
Other long-term liabilities	1,139	1,121
Total liabilities	163,269	163,808
Commitments and contingencies (Note 11)
Shareholders' equity:
Ordinary shares, including non-voting ordinary shares, £0.01 nominal value; 159,802,729 and 155,876,645 shares authorized on June 30, 2025 and December 31, 2024, respectively; 69,253,944 and 69,061,418 shares issued and outstanding at June 30, 2025 and December 31, 2024, respectively	893	890
Additional paid-in capital	1,491,882	1,472,842
Accumulated other comprehensive (loss) income	(3,363)	119
Accumulated deficit	(820,497)	(680,791)
Total shareholders' equity	668,915	793,060
Total liabilities and shareholders' equity	$ 832,184	$ 956,868