Property and Equipment, Net - Schedule of Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 1,443	$ 1,414
Less: Accumulated depreciation	(1,297)	(1,232)
Property and equipment, net	146	182
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	228	228
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,081	1,035
Computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	134	134
Lab equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 0	$ 17

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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