Property and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Property and equipment
Property and equipment, gross	$ 3,069	$ 1,904
Less: accumulated depreciation	(732)	(610)
Property and equipment	2,337	1,294
Laboratory equipment
Property and equipment
Property and equipment, gross	1,771	1,756
Leasehold improvements
Property and equipment
Property and equipment, gross	899
Office furniture and equipment
Property and equipment
Property and equipment, gross	$ 398	$ 148

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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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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