Property and equipment - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Property, Plant and Equipment [Line Items]
Property and equipment	$ 6,335	$ 10,395
Less: accumulated depreciation	(6,335)	(5,320)
Property and equipment, net	0	5,075
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment	1,472	3,873
Laboratory equipment
Property, Plant and Equipment [Line Items]
Property and equipment	2,949	4,415
Office equipment
Property, Plant and Equipment [Line Items]
Property and equipment	770	970
Hardware and computer software
Property, Plant and Equipment [Line Items]
Property and equipment	$ 1,144	$ 1,137

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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