Nature of the business (Details) - USD ($)	1 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended
	Jan. 31, 2023	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022	Jan. 04, 2023	Oct. 14, 2021	Oct. 01, 2021
Net loss		$ 5,557,000	$ 8,924,000	$ 9,827,000	$ 20,577,000
Accumulated deficit		125,828,000		125,828,000		$ 116,001,000
Proceeds from sales of equity and debt				155,200,000
Reimbursement expenses received						17,600,000
Securities aggregate price								$ 200,000,000.0
Cash and cash equivalents		$ 38,416,000	$ 34,649,000	38,416,000	$ 34,649,000	$ 20,323,000
Proceeds from issuance of common stock				$ 34,000
Collaboration agreement with AbbVie
Upfront payment	$ 30,000,000.0
Additional upfront payment							$ 30,000,000.0
Collaboration agreement with AbbVie | Maximum
Potentially eligible amount receivable							$ 2,800,000,000
Open Market Sale
Sale of common stock	5,925			5,925
Proceeds from issuance of common stock	$ 34,000			$ 34,000
Open Market Sale | Maximum
Securities aggregate price									$ 75,000,000.0