Property and Equipment, Net - Schedule of Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 2,273	$ 1,511
Less: Accumulated depreciation and amortization	(641)	(274)
Property and equipment, net	1,632	1,237
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	1,287	910
Computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	152	47
Software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	33	33
Lab equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 573	$ 293

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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