Segment reporting - Segment Expenses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Segment Reporting Information
Research and development expense	$ 19,249	$ 17,985	$ 56,071	$ 45,482
Stock-based compensation	4,396	5,508	14,093	14,401
Depreciation and amortization	2,842	3,355	8,914	10,155
Total operating expenses	30,532	30,596	91,426	82,983
Segment One
Segment Reporting Information
Personnel	10,488	9,813	30,638	29,137
Stock-based compensation	4,396	5,508	14,093	14,401
General & administrative	3,531	3,799	11,158	11,352
Depreciation and amortization	2,842	3,355	8,914	10,155
Total operating expenses	30,532	30,596	91,426	82,983
Asset Impairment Charges	0	1,125	0	1,125
Drug creation program and platform \| Segment One
Segment Reporting Information
Research and development expense	5,669	4,144	14,963	11,635
External preclinical and clinical development \| Segment One
Segment Reporting Information
Research and development expense	$ 3,606	$ 2,852	$ 11,660	$ 5,178

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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