Condensed Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Cash Flows from Operating Activities:
Net loss	$ (48,802)	$ (53,898)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	1,421	1,112
Loss on disposal of property and equipment	0	20
Stock-based compensation	7,195	4,219
Other noncash compensation	199	269
Issuance of common stock for license rights	0	6,548
Amortization of premium/(discount) on investment securities	(5,991)	519
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	(1,026)	(731)
Accounts payable and accrued liabilities	1,765	929
Operating lease right-of-use assets and liabilities, net	(21)	121
Net cash used in operating activities	(45,260)	(40,892)
Cash Flows from Investing Activities:
Purchases of property and equipment	(31,811)	(6,296)
Purchases of investment securities	(292,489)	(50,082)
Sales and maturities of investment securities	177,530	104,448
Net cash provided by (used in) investing activities	(146,770)	48,070
Cash Flows from Financing Activities:
Proceeds from issuance of common stock in initial public offering, net of issuance costs	310,947	0
Proceeds from issuance of convertible preferred stock, net of issuance costs	0	159,684
Proceeds from exercise of vested and unvested common stock options	3,888	87
Repurchase of common stock	0	(1,876)
Net cash provided by financing activities	314,835	157,895
Net increase in cash, cash equivalents and restricted cash	122,805	165,073
Cash, cash equivalents and restricted cash, beginning of period	129,498	50,851
Cash, cash equivalents and restricted cash, end of period	252,303	215,924
Supplemental Disclosure of Noncash Activities:
Issuance of common stock for license rights	0	6,548
Vesting of common stock	722	620
Unpaid property and equipment purchases	6,487	1,335
Right-of-use assets and operating lease liabilities	0	2,345
Unpaid equity offering costs	545	335
Conversion of preferred stock to common stock upon initial public offering	415,258	0
Deemed dividend upon down round of equity offerings	$ 1,209	$ 4,550