Property and equipment, net (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Property and equipment, net
Property and equipment, gross	$ 5,025		$ 4,975
Less: Accumulated depreciation and amortization	(2,822)		(2,683)
Property and equipment, net	2,203		2,292
Depreciation expense	300	$ 200
Laboratory equipment
Property and equipment, net
Property and equipment, gross	4,256		4,326
Leasehold improvements
Property and equipment, net
Property and equipment, gross	363		300
Computer equipment and software
Property and equipment, net
Property and equipment, gross	222		229
Furniture and office equipment
Property and equipment, net
Property and equipment, gross	$ 184		$ 120

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.

+ References

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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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