Consolidated statements of cash flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Cash flows from operating activities:
Net loss	$ (104,699)	$ (101,067)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	2,469	1,546
Amortization and accretion of marketable securities	(325)	(211)
Stock-based compensation	25,257	22,854
Loss on disposal of property and equipment	1
Reduction in the carrying amount of right of use assets	2,260	1,989
Changes in assets and liabilities:
Prepaid expenses and other current assets	529	(5,183)
Accounts payable, accrued liabilities, and operating leases	(3,208)	(3,530)
Deferred revenue	(3,351)	51,736
Net cash used in operating activities	(81,067)	(31,866)
Cash flows from investing activities:
Purchases of property and equipment	(1,616)	(3,962)
Purchases of marketable securities	0	(201,320)
Sales of marketable securities	107,562	159,400
Net cash provided by (used in) investing activities	105,946	(45,882)
Cash flows from financing activities:
Proceeds from issuance of common stock upon exercise of stock options	371	494
Proceeds from Employee Stock Purchase Plan	555	570
Proceeds from controlled equity offering sales agreement	52,081	45,344
Other	0	1
Net cash provided by financing activities	53,007	46,409
Net increase (decrease) in cash, cash equivalents and restricted cash	77,886	(31,339)
Cash, cash equivalents and restricted cash—beginning of year	114,125	145,464
Cash, cash equivalents and restricted cash—end of year	192,011	114,125
Supplemental Disclosure of Non-Cash Investing and Financing Activities:
Right-of-use assets recognized in exchange for operating leases	4,118	1,802
Property and equipment included in accrued expense and accounts payable	$ 0	$ 121