CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Cash flows from operating activities:
Net loss	$ (846,422)	$ (408,168)	$ (570,279)
Adjustments to reconcile net loss to net cash used in operating activities:
Non-cash share-based compensation	71,963	28,787	193,556
Acquisition of IPR&D asset	10,811	0	93,747
Impairment of Artizan preferred stock	0	0	10,000
Depreciation and amortization	7,855	6,912	1,386
Issuance of common shares or warrants for license agreement	3,340		1,779
Issuance of common shares as payment for license agreement	71,627	21,814	0
Obligation to issue common shares as payment for license agreements and other arrangements	8,554	0	0
Fair value of forward contract and derivative liabilities under license agreement	102,529	0	0
Change in fair value of forward contract and derivative liabilities	(17,819)	0	0
Other non-cash items	(11,702)	(5,683)	726
Changes in operating assets and liabilities:
Prepaid expenses, income tax receivable, and other current and non-current assets	8,043	27,176	(41,336)
Accounts payable	710	4,874	5,928
Accrued expenses and other current and non-current liabilities	8,058	(7,437)	6,804
Net cash used in operating activities	(582,453)	(331,725)	(297,689)
Cash flows from investing activities:
Proceeds from maturities of marketable securities	504,364	322,079	0
Proceeds from sales of marketable securities	0	4,920	0
Purchases of marketable securities	(745,680)	(194,121)	(259,716)
Purchases of property and equipment	(4,049)	(3,048)	(6,074)
Payment for IPR&D asset acquisition	0	0	(35,000)
Cash acquired in business acquisition	391	0	0
Purchase of Artizan preferred stock	0	0	(4,000)
Net cash (used in) provided by investing activities	(244,974)	129,830	(304,790)
Cash flows from financing activities:
Net transfers from Former Parent	0	0	449,130
Change in restricted cash due to Former Parent	0	(35,212)	35,212
Proceeds from issuance of common shares	666,165	243,225	283,804
Payments of issuance costs	(2,150)	(800)	(1,000)
Proceeds from issuance of common shares under 2022 Equity Incentive Plan and 2022 Employee Share Purchase Plan	11,501	4,695	451
Other financing activities, net	2,258	0	0
Net cash provided by financing activities	677,774	211,908	767,597
Effect of exchange rates on cash, cash equivalents and restricted cash	75	(497)	429
Net (decrease) increase in cash, cash equivalents and restricted cash	(149,578)	9,516	165,547
Cash, cash equivalents and restricted cash at beginning of period	252,120	242,604	77,057
Cash, cash equivalents and restricted cash at end of period	102,542	252,120	242,604
Supplemental disclosure of cash flow information:
Cash paid for interest	125	0	0
Cash (received) paid for income taxes	$ (10,444)	$ (33,300)	$ 38,165