Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Net Loss	$ (110,290)	$ (196,300)
Adjustments to reconcile net loss to net cash used in operating activities:
Non-cash share consideration, issued in acquisition of IPR&D	0	9,415
Non-cash operating lease expense (benefit)	303	(106)
Depreciation expense	1,006	525
Share based compensation expense	19,148	8,664
Amortization of discounts on investments, net	(1,607)	(23)
Unrealized foreign currency transaction loss, net	127	87
Non-cash consideration relating to Pfizer Commercial Agreement	(20,000)	0
Non-cash write off of non-recourse promissory note	4,133	0
Changes in operating assets and liabilities:
Decrease (increase) in prepaid expenses and other current assets	1,328	(8,176)
(Increase) decrease in other receivable	(1,400)	14,216
Decrease (increase) in other non-current assets	27	(40)
Decrease in accounts payable	(1,705)	(1,708)
Increase in accrued expenses	9,842	8,761
(Decrease) increase in other current liabilities	(97)	732
Net cash used in operating activities	(99,185)	(163,953)
Cash flows from investing activities:
Purchase of property and equipment	(1,845)	(947)
Purchase of marketable securities	(303,136)	(154,990)
Sales and redemptions of marketable securities	235,780	0
Net cash used for investing activities	(69,201)	(155,937)
Cash flows from financing activities:
Proceeds from exercise of share options	1,710	5,546
Proceeds from issuance of ordinary shares upon initial public offering	0	311,083
Proceeds from issuance of redeemable convertible preferred shares	0	3,000
Net cash provided by financing activities	1,710	313,273
Effect of exchange rate changes on cash and cash equivalents	(2,212)	449
Net decrease in cash, cash equivalents and restricted cash	(168,888)	(6,168)
Cash and cash equivalents, and restricted cash—beginning of period	248,182	254,350
Cash and cash equivalents, and restricted cash—ending of period	79,294	248,182
Cash and cash equivalents—end of period	79,221	228,182
Restricted cash—end of period	73	20,000
Cash and cash equivalents, and restricted cash—ending of period	79,294	248,182
Supplemental disclosure of cash information
Cash paid for income taxes	375	0
Supplemental disclosure of non-cash financing and investing activities:
Right-of-use assets obtained in exchange for lease obligations	1,110	5,160
Ordinary shares received as consideration for non-recourse promissory note default	1,650	0
Issuance costs in accounts payable and other accrued liabilities	0	1,496
Purchase of property and equipment in accounts payable	551	613
Ordinary Shares
Cash flows from financing activities:
Issuance costs	0	(6,296)
Redeemable Convertible Preferred Shares
Cash flows from financing activities:
Issuance costs	0	(60)
Conversion of Preferred Shares
Supplemental disclosure of non-cash financing and investing activities:
Conversion of stock	0	352,730
Conversion of Warrants
Supplemental disclosure of non-cash financing and investing activities:
Conversion of stock	$ 0	$ 10,414