Condensed Consolidated Balance Sheets - USD ($)	Sep. 30, 2023	Dec. 31, 2022
Current assets
Cash and cash equivalents	$ 381,738,000	$ 267,110,000
Short-term marketable securities	406,693,000	47,510,000
Prepaid expenses and other current assets	6,207,000	1,444,000
Total current assets	794,638,000	316,064,000
Prepaid expenses and other assets, non-current	2,482,000	3,859,000
Operating lease, right-of-use asset	1,240,000	0
Property, plant and equipment, net	2,129,000	0
Total assets	800,489,000	319,923,000
Current liabilities
Accounts payable	18,702,000	5,947,000
Accrued research and development expenses	41,295,000	5,717,000
Accrued compensation and other current liabilities	5,144,000	4,237,000
Severance liability	1,720,000	0
Total current liabilities	66,861,000	15,901,000
Derivative tranche liability	0	10,291,000
Operating lease liability, non-current	1,252,000	0
Total liabilities	68,113,000	26,192,000
Commitments and contingencies (Note 8)
Redeemable convertible preferred shares, no par value; no shares authorized, issued and outstanding as of September 30, 2023; 104,461,636 shares authorized as of December 31, 2022; par value of $0.00001 per share; 40,743,522 shares issued and outstanding as of December 31, 2022; aggregate liquidation preference $408,000 as of December 31, 2022	0	396,593,000
Stockholders’ equity (deficit)
Preferred stock, 10,000,000 shares authorized, $0.00001 par value, no shares issued and outstanding at September 30, 2023; no shares authorized, issued, and outstanding at December 31, 2022	0	0
Common stock, par value of $0.00001 per share; 790,000,000 and 229,461,636 shares authorized as of September 30, 2023 and December 31, 2022, respectively; 97,240,419 and 2,767,359 shares issued and outstanding as of September 30, 2023 and December 31, 2022, respectively	1,000	0
Additional paid-in capital	1,125,932,000	4,302,000
Accumulated other comprehensive loss	(50,000)	(86,000)
Accumulated deficit	(393,507,000)	(107,078,000)
Total stockholders' equity (deficit)	732,376,000	(102,862,000)
Total liabilities, redeemable convertible preferred stock and stockholders’ equity (deficit)	$ 800,489,000	$ 319,923,000