Property and Equipment, Net - Schedule of Estimated Useful Lives of Assets and Property and Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 636	$ 568
Accumulated depreciation	(539)	(462)
Property and equipment, net	97	106
Computer Equipment and Software
Property Plant And Equipment [Line Items]
Property and equipment, gross	116	116
Furniture, Fixtures, and Other
Property Plant And Equipment [Line Items]
Property and equipment, gross	154	147
Laboratory Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	350	289
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 16	$ 16

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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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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