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Property and equipment (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
Property and equipment (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Property Plant And Equipment [Line Items]
Property and equipment	$ 15,622		$ 15,622		$ 15,521
Less: accumulated depreciation	(11,473)		(11,473)		(10,777)
Total property and equipment, net	4,149		4,149		4,744
Depreciation expense	336	$ 416	696	$ 780
Laboratory equipment
Property Plant And Equipment [Line Items]
Property and equipment	8,861		8,861		8,819
Leasehold improvements
Property Plant And Equipment [Line Items]
Property and equipment	4,548		4,548		4,548
Furniture and fixtures
Property Plant And Equipment [Line Items]
Property and equipment	1,435		1,435		1,435
Office equipment
Property Plant And Equipment [Line Items]
Property and equipment	621		621		621
Computer equipment
Property Plant And Equipment [Line Items]
Property and equipment	$ 157		$ 157		$ 98