Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($)	6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024
Operating activities
Net loss	$ (257,089,000)	$ (200,828,000)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	5,370,000	4,104,000
Stock–based compensation expense	50,547,000	52,940,000
Net accretion of discounts on marketable securities	(6,585,000)	(20,574,000)
Non-cash adjustment to operating lease expense	(2,161,000)	(1,976,000)
Right-of-use asset amortization for finance lease	1,798,000	0
Non-cash gain from divestiture of small molecule programs	0	(14,537,000)
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	(3,650,000)	(20,336,000)
Other non-current assets	3,022,000	0
Accounts payable	(43,000)	4,523,000
Accruals and other current liabilities	(14,151,000)	(18,496,000)
Deferred research and development funding liability	16,176,000	10,340,000
Net cash used in operating activities	(206,766,000)	(204,840,000)
Investing activities
Purchases of marketable securities	(137,926,000)	(955,802,000)
Maturities and sales of marketable securities	323,965,000	608,120,000
Purchases of property and equipment	(9,356,000)	(6,936,000)
Net cash provided by (used in) investing activities	176,683,000	(354,618,000)
Financing activities
Proceeds from issuance of common stock and pre-funded warrants, net of issuance costs of $480	0	499,253,000
Proceeds from exercise of awards under equity incentive plans	4,652,000	7,778,000
Payments for finance lease right-of-use asset	(6,791,000)	0
Net cash (used in) provided by financing activities	(2,139,000)	507,031,000
Net decrease in cash, cash equivalents and restricted cash	(32,222,000)	(52,427,000)
Cash, cash equivalents and restricted cash at beginning of period	176,535,000	128,681,000
Cash, cash equivalents and restricted cash at end of period	144,313,000	76,254,000
Supplemental disclosures of cash flow information
Equity consideration received in the divestiture of small molecule programs (Note 10)	$ 0	$ 15,000,000