Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Cash flows from operating activities:
Net loss	$ (130,751)	$ (109,089)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	26,642	9,366
Depreciation and amortization expense	785	843
Non-cash lease expense	298	454
Accretion of premium on marketable securities	(1,792)	(543)
Loss on sale of marketable securities	0	23
Loss (gain) on disposal of property and equipment	(2)	118
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	(7,207)	4,175
Accounts payable and other liabilities	(21,378)	(7,897)
Net cash used in operating activities	(133,405)	(102,550)
Cash flows from investing activities:
Purchases of property and equipment	(1,048)	(480)
Purchases of marketable securities	(207,691)	(34,684)
Maturities of marketable securities	40,076	77,629
Sales of marketable securities	0	1,829
Net cash (used in) provided by investing activities	(168,663)	44,294
Cash flows from financing activities:
Proceeds from issuance of common stock in public offering, net of issuance costs	675,180	0
Proceeds from issuance of common stock in at-the-market offering, net of issuance costs	97,871	52,370
Proceeds from exercise of stock options	15,199	1,351
Net cash provided by financing activities	788,250	53,721
Net increase (decrease) in cash, cash equivalents and restricted cash	486,182	(4,535)
Cash, cash equivalents and restricted cash, beginning of period	123,941	174,466
Cash, cash equivalents and restricted cash, end of period	610,123	169,931
Supplemental disclosures of cash flow information:
Purchase of property and equipment in accounts payable	$ 0	$ 10