Condensed Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Cash flows from operating activities:
Net loss	$ (23,934)	$ (25,835)
Adjustments to reconcile net loss to net cash used in operating activities:
Net amortization of premiums and discounts on marketable securities	(1,562)	45
Depreciation and amortization	654	440
Noncash lease expense	1,566	1,452
Stock-based compensation expense	3,263	3,342
Changes in assets and liabilities:
Prepaid expenses and other current assets and other assets	1,457	(71)
Accounts payable	(591)	582
Accrued compensation	(2,485)	(1,666)
Accrued research costs	(124)	1,246
Accrued expenses and other current liabilities and other liabilities	1,935	323
Operating lease liabilities	(1,253)	(1,098)
Net cash used in operating activities	(21,074)	(21,240)
Cash flows from investing activities:
Purchases of property and equipment	(383)	(3,273)
Purchases of investments in marketable securities	(28,129)	(167,393)
Proceeds from maturities of marketable securities	71,675	0
Net cash provided by (used in) investing activities	43,163	(170,666)
Cash flows from financing activities:
Repurchase of unvested early exercised shares	(8)	0
Net cash used in financing activities	(8)	0
Net increase (decrease) in cash, cash equivalents and restricted cash	22,081	(191,906)
Cash, cash equivalents and restricted cash, at beginning of period	49,446	378,692
Cash, cash equivalents and restricted cash, at end of period	71,527	186,786
Reconciliation of cash, cash equivalents and restricted cash to statement of financial position:
Cash and cash equivalents	69,811	185,070
Restricted cash	1,716	1,716
Cash, cash equivalents and restricted cash in statement of financial position	71,527	186,786
Supplemental disclosures of non-cash investing and financing information:
Property and equipment purchases in accounts payable and accrued expenses	(4,655)	(109)
Lessor funded lease incentive additions included in property and equipment	7,193	0
Vesting of early exercised stock options	$ 25	$ 51