Share-based compensation - Share based compensation expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Share based compensation expense
Total share-based compensation expense	$ 5,368	$ 2,688	$ 21,239	$ 9,084
Research and development expenses
Share based compensation expense
Total share-based compensation expense	2,637	1,238	7,643	3,535
General and administrative expenses
Share based compensation expense
Total share-based compensation expense	$ 2,731	$ 1,450	$ 13,596	$ 5,549