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Nature of business and basis of presentation (Details) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2024 USD ($) candidate	Jun. 30, 2024 USD ($)	Mar. 31, 2024 USD ($)	Sep. 30, 2023 USD ($)	Jun. 30, 2023 USD ($)	Mar. 31, 2023 USD ($)	Sep. 30, 2024 USD ($) candidate	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of additional preclinical candidates | candidate	2						2
Net loss	$ (11,501)	$ (24,268)	$ (19,306)	$ (41,656)	$ (54,307)	$ (56,163)	$ (55,075)	$ (152,126)
Accumulated deficit	$ (881,436)						$ (881,436)		$ (826,361)

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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