Property and equipment, net (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property, Plant, and Equipment and Finance Lease Right-of-Use Asset, after Accumulated Depreciation and Amortization [Abstract]
Property, plant and equipment, gross	$ 3,884	$ 3,805
Less accumulated depreciation and amortization	(3,029)	(2,274)
Property and equipment, net	855	1,531
Lab equipment
Property, Plant, and Equipment and Finance Lease Right-of-Use Asset, after Accumulated Depreciation and Amortization [Abstract]
Property, plant and equipment, gross	3,513	3,506
Leasehold improvements
Property, Plant, and Equipment and Finance Lease Right-of-Use Asset, after Accumulated Depreciation and Amortization [Abstract]
Property, plant and equipment	193	185
Computer equipment
Property, Plant, and Equipment and Finance Lease Right-of-Use Asset, after Accumulated Depreciation and Amortization [Abstract]
Property, plant and equipment	156	96
Office equipment and furniture and fixtures
Property, Plant, and Equipment and Finance Lease Right-of-Use Asset, after Accumulated Depreciation and Amortization [Abstract]
Property, plant and equipment	$ 22	$ 18