Property and Equipment - (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Total property and equipment, gross	$ 3,533	$ 3,389
Less: Accumulated depreciation	(2,311)	(1,919)
Total property and equipment, net	1,222	1,470
Laboratory equipment
Total property and equipment, gross	1,562	1,514
Computer equipment and software
Total property and equipment, gross	319	318
Furniture and fixtures
Total property and equipment, gross	44	44
Leasehold improvements
Total property and equipment, gross	1,449	1,412
Construction-in-process
Total property and equipment, gross	$ 159	$ 101

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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