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	$ (465,892)	$ (373,630)	$ (295,350)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	79,880	49,735	31,625
Depreciation and amortization expense	1,096	527	467
Amortization of debt issuance costs and discount	2,089	2,414	797
Amortization and interest accretion related to operating leases	(400)	0	0
Changes in operating assets and liabilities:
Trade receivables, net	(53,822)	0	0
Inventory	(34,068)	0	0
Prepaid expenses and other current assets	(10,636)	(555)	(1,257)
Accounts payable	15,558	4,210	2,451
Accrued liabilities	34,715	(1,481)	36,413
Accrued interest, net of interest received on maturity of investments	(24,092)	(5,450)	(3)
Net cash used in operating activities	(455,572)	(324,230)	(224,857)
Cash flows from investing activities:
Purchases of marketable securities	(1,131,207)	(834,439)	(143,478)
Sales and maturities of marketable securities	863,283	333,398	350,381
Acquisition of intangible asset	(5,000)	0	0
Purchases of property and equipment, net of disposals	(1,462)	(1,479)	(217)
Net cash provided by (used in) investing activities	(274,386)	(502,520)	206,686
Cash flows from financing activities:
Proceeds from issuance of loan payable	0	65,000	50,000
Payment of debt issuance costs	0	(363)	(886)
Net cash provided by financing activities	735,062	595,116	313,451
Net increase (decrease) in cash and cash equivalents	5,104	(231,634)	295,280
Cash, cash equivalents, and restricted cash at beginning of period	99,915	331,549	36,269
Cash, cash equivalents, and restricted cash at end of period	105,019	99,915	331,549
Supplemental disclosure of cash flow information:
Obtaining a right-of-use asset in exchange for a lease liability	1,330	1,628	583
Nonrelated Party
Cash flows from financing activities:
Proceeds from issuance or sale of equity	397,487	260,187	255,382
Related Party
Cash flows from financing activities:
Proceeds from issuance or sale of equity	$ 337,575	$ 270,292	$ 8,955