Property and Equipment, Net (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Property and Equipment, Net
Property and equipment, gross	$ 226	$ 226
Less: accumulated depreciation	(206)	(190)
Property and equipment, net	20	36
Depreciation expense	16	29
Computer office equipment
Property and Equipment, Net
Property and equipment, gross	51	51
Leasehold improvements
Property and Equipment, Net
Property and equipment, gross	69	69
Lab equipment
Property and Equipment, Net
Property and equipment, gross	76	76
Furnitures and fixtures
Property and Equipment, Net
Property and equipment, gross	$ 30	$ 30

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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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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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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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services 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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