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	$ (103,691)	$ (63,650)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	25,306	24,888
Depreciation and amortization expense	208	208
Accretion of premium and discounts on marketable securities	(6,512)	(6,784)
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	8,194	1,449
Other assets		98
Accounts payable	1,218	1,411
Accrued expenses and other liabilities	(6,703)	(3,510)
Operating lease liabilities	(87)	(80)
Net cash used in operating activities	(82,067)	(45,970)
Cash flows from investing activities
Purchases of marketable securities	(174,460)	(309,844)
Sales and maturities of marketable securities	355,948	380,889
Net cash provided by investing activities	181,488	71,045
Cash flows from financing activities
Proceeds from issuance of common stock under ESPP	150	165
Net cash provided by financing activities	150	165
Net increase in cash, cash equivalents and restricted cash	99,571	25,240
Cash, cash equivalents and restricted cash at the beginning of period	143,823	188,658
Cash, cash equivalents and restricted cash at the end of period	243,394	213,898
Cash, cash equivalents and restricted cash at the end of period:
Cash and cash equivalents	243,394	213,700
Restricted cash		198
Total cash, cash equivalents and restricted cash	$ 243,394	$ 213,898