Balance Sheet Components - Schedule of Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 1,216	$ 1,051
Property and equipment, accumulated depreciation	(603)	(342)
Property and equipment, net	613	709
Lab Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	271	271
Computer Equipment and Software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	669	520
Furniture [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	116	111
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	101	80
Construction in progress [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 59	$ 69

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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