Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Effective Income Tax Rate Reconciliation [Line Items]
Expected tax benefit at statutory rate	$ (13,730)	$ (6,033)
State income tax, net of federal benefit	(3,531)	(1,024)
Permanent and other	272	118
Change in fair value of SAFEs	755
Stock-based compensation expense	(1,479)	1,109
Executive compensation expense	1,626
Research credits	(2,794)	(3,106)
Change in state and local tax rate		(2,335)
Change in valuation allowance	18,881	11,343
Provision for income taxes	$ 0	$ 72