Amgen license agreement (Details) - USD ($)	1 Months Ended		3 Months Ended			9 Months Ended
	Nov. 30, 2018	Jun. 30, 2018	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2019	Sep. 30, 2024	Sep. 30, 2023
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and development expense			$ 72,232,000	$ 38,634,000		$ 178,204,000	$ 88,406,000
Amgen Agreement
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Initial fair value of the anti-dilution right liability	$ 7,404,000
Payment for clinical trail					$ 2,500,000
Obligation for payment in connection with dosing of the first patient					7,500,000
Amgen Agreement | Maximum
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Aggregate milestone payments upon the achievement of specified commercial milestones					75,000,000
Payment in connection with dosing of the first patient					$ 30,000,000
Amgen Agreement | Research and development expense
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and development expense			$ 0	$ 0		$ 0	$ 0
Amgen Agreement | Amgen
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Upfront payment		$ 5,000,000
Amgen Agreement | Series A Preferred Stock
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Share Issued under agreement	3,205,128
Amgen Agreement | Series A Preferred Stock | Amgen
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Share Issued under agreement		2,653,333
Share Issued value under agreement		$ 1,353,000
Ownership Interest [Member] | Amgen Agreement | Amgen
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Ownership interest of the outstanding shares (as a percent)		10.00%