Nature of business and basis of presentation (Details) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2024 USD ($) candidate	Mar. 31, 2024 USD ($)	Jun. 30, 2023 USD ($)	Mar. 31, 2023 USD ($)	Jun. 30, 2024 USD ($) candidate	Jun. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of additional preclinical candidates | candidate	2				2
Net loss	$ (24,268)	$ (19,306)	$ (54,307)	$ (56,163)	$ (43,574)	$ (110,470)
Accumulated deficit	$ (869,935)				$ (869,935)		$ (826,361)