Nature of business and basis of presentation (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended
	May 16, 2022	Jun. 30, 2022	Sep. 30, 2022	Dec. 31, 2021
Common stock, par value (in dollars per share)			$ 0.001	$ 0.001
Cash			$ 33.1
Atrin Pharmaceuticals, Inc
Number of shares to purchase under option	3,275,149
Common Stock | Atrin Pharmaceuticals, Inc
Issuance of common stock upon acquisition of Atrin (in shares)	1,117,394
Common stock, par value (in dollars per share)	$ 0.001
Series A Preferred Stock | Atrin Pharmaceuticals, Inc
Issuance of preferred stock upon acquisition of Atrin (in shares)	2,949,630	2,949,630
Conversion value of temporary equity	$ 68.8