Property and equipment - Summary of Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Total, at cost	$ 13,442	$ 12,250
Accumulated depreciation	(7,262)	(4,243)
Total, net	6,180	8,007
Leasehold improvements [Member]
Property, Plant and Equipment [Line Items]
Total, at cost	5,940	5,655
Lab equipment [Member]
Property, Plant and Equipment [Line Items]
Total, at cost	5,709	4,833
Computer equipment [Member]
Property, Plant and Equipment [Line Items]
Total, at cost	994	942
Furniture and office equipment [Member]
Property, Plant and Equipment [Line Items]
Total, at cost	472	459
Vehicles [Member]
Property, Plant and Equipment [Line Items]
Total, at cost	305	296
Asset under construction [Member]
Property, Plant and Equipment [Line Items]
Total, at cost	$ 22	$ 65