Property and Equipment, net - Property and Equipment, net (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 2,381	$ 2,032
Less accumulated depreciation and amortization	1,541	1,332
Property, Plant and Equipment, net, Total	840	700
Computer and Office Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	211	211
Laboratory Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	628	628
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	330	61
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 1,212	$ 1,132

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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