CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOW - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Cash flows from operating activities:
Net loss	$ (110,771)	$ (98,123)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	2,358	2,249
Amortization and premium of marketable securities, net	(12,386)	(4,043)
Loss on sale or disposal of assets	12
Stock-based compensation expense	24,462	16,678
Changes in operating assets and liabilities:
Accounts and other receivables	1,776	95
Prepaid and other current assets	(19,961)	1,757
Other assets	(9,640)	(3)
Accounts payable and accrued expenses	3,640	5,507
Other liabilities	(4,792)	1,125
Net cash used in operating activities	(125,302)	(74,758)
Cash flows from investing activities:
Sales and maturities of marketable securities	347,732	249,703
Purchases of marketable securities	(660,745)	(183,172)
Acquisition of property and equipment	(1,163)	(1,152)
Net cash (used in) provided by investing activities	(314,176)	65,379
Cash flows from financing activities:
Net proceeds from stock issuances	432,298
Proceeds from issuance of stock from employee benefit plans	8,765	1,084
Net cash provided by financing activities	441,063	1,084
Net increase (decrease) in cash and cash equivalents	1,585	(8,295)
Cash and cash equivalents at beginning of period	34,814	29,429
Cash and cash equivalents at end of period	36,399	21,134
Non-cash investing activities
Accrued construction in progress	$ 232	$ 488