Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
CASH FLOWS FROM OPERATING ACTIVITIES
Net loss	$ (43,857)	$ (18,422)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	13,835	1,709
Change in fair value of derivative liability	430	0
Net accretion of discount on marketable securities	(2,423)	(107)
Depreciation and amortization	0	384
Amortization of operating lease assets	0	164
Other	0	2
Changes in operating assets and liabilities:
Accounts payable	2,210	1,384
Accrued and other liabilities	8,151	(3,164)
Related party payable	(6,507)	0
Prepaid expenses and other assets	(381)	622
Deferred revenue	0	(53)
Development receivables	0	45
Operating lease liabilities	0	(198)
Net cash used in operating activities	(28,542)	(17,634)
CASH FLOWS FROM INVESTING ACTIVITIES
Purchases of marketable securities	(152,713)	0
Proceeds from maturities and sales of marketable securities	47,750	17,750
Net cash (used in) and provided by investing activities	(104,963)	17,750
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from issuance of Series B non-voting convertible preferred stock in connection with private placement, net of placement and other offering costs	169,205	0
Payments related to contingent value rights liability	(1,430)	0
Proceeds from employee stock plan purchases and stock option exercises	4,390	18
Principal payments on finance lease obligation	0	(8)
Net cash provided by financing activities	172,165	10
Effect of exchange rate on cash, cash equivalents, and restricted cash	(4)	11
NET INCREASE IN CASH, CASH EQUIVALENTS, AND RESTRICTED CASH	38,656	137
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH
Beginning of period	189,215	36,416
End of period	227,871	36,553
Supplemental Disclosure of Non-Cash Investing and Financing Information:
Unpaid amounts related to issuance of Series B non-voting convertible preferred stock in connection with private placement	$ 355	$ 0