Stock-based compensation - Equity Incentive Plan (Details) - Equity Incentive Plan 2024 [Member] - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2025	Jun. 30, 2024
Stock-based compensation [Abstract]
Compensation expense	$ 302	$ 238
Research and Development Expenses [Member]
Stock-based compensation [Abstract]
Compensation expense	69	65
General and Administrative Expenses [Member]
Stock-based compensation [Abstract]
Compensation expense	$ 233	$ 173

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details