Condensed Statements of Cash Flows (unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Cash flows from operating activities
Net loss	$ (99,419)	$ (79,925)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	920	636
Stock-based compensation expense	18,557	12,746
Amortization of premiums and discounts on marketable securities, net	(5,071)	223
Non-cash operating lease costs	1,420	1,379
Changes in operating assets and liabilities:
Prepaid and other assets	(5,642)	(251)
Accounts payable and accrued liabilities	(816)	6,582
Accrued compensation	(4,663)	(4,253)
Operating lease liabilities	(1,594)	(251)
Deferred revenue	(2,466)	(2,006)
Net cash used in operating activities	(98,774)	(65,120)
Cash flows from investing activities
Maturities of marketable securities	128,215	21,525
Purchases of marketable securities	(275,404)	(212,564)
Purchases of property and equipment	(2,442)	(2,080)
Net cash used in investing activities	(149,631)	(193,119)
Cash flows from financing activities
Proceeds from issuance of common stock in public offerings, net of issuance costs	60,547	62,384
Proceeds from issuance of common stock under employee incentive equity plans	1,386	513
Net cash provided by financing activities	61,933	62,897
Net decrease in cash, cash equivalents and restricted cash	(186,472)	(195,342)
Cash, cash equivalents and restricted cash at beginning of period	340,647	320,699
Cash, cash equivalents and restricted cash at end of period	$ 154,175	$ 125,357