CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOW - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024
Cash flows from operating activities:
Net loss	$ (110,396)	$ (68,650)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	1,740	1,572
Amortization and premium of marketable securities, net	(3,955)	(8,053)
Loss on sale or disposal of assets	6	8
Stock-based compensation expense	18,507	14,842
Changes in operating assets and liabilities:
Accounts and other receivables	610	1,094
Prepaid and other current assets	3,020	(5,610)
Other assets	447
Accounts payable and accrued expenses	(6,632)	(3,067)
Other liabilities	(1,724)	(2,101)
Net cash used in operating activities	(98,377)	(69,965)
Cash flows from investing activities:
Sales and maturities of marketable securities	367,873	199,370
Purchases of marketable securities	(274,080)	(560,686)
Acquisition of property and equipment	(993)	(618)
Net cash provided by (used in) investing activities	92,800	(361,934)
Cash flows from financing activities:
Net proceeds from stock issuances		432,298
Proceeds from issuance of stock from employee benefit plans	265	7,526
Net cash provided by financing activities	265	439,824
Net (decrease) increase in cash and cash equivalents	(5,312)	7,925
Cash and cash equivalents at beginning of period	28,356	34,814
Cash and cash equivalents at end of period	23,044	42,739
Non-cash investing activities
Accrued construction in progress	$ 49	$ 17