Property and Equipment, Net - Schedule of Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 1,505	$ 667
Less: Accumulated depreciation and amortization	(171)	(264)
Property and equipment, net	1,334	403
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	216	299
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	913	139
Computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	47	37
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	$ 296	$ 159

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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