Accrued expenses and other current liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Accrued expenses and other current liabilities
Salaries and bonuses	$ 4,490	$ 4,754
Social security contributions	229	250
Unearned grant income (current)	329	693
Sublicense fees		304
Accrued external research and development expenses	1,878	2,165
Accrued external general and administration expenses	531	629
Accrued for property and equipment acquisitions	0	7
Finance lease liabilities	0	21
Other accruals and liabilities	300	57
Total	$ 7,757	$ 8,880