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Share-based compensation (Details)			1 Months Ended			6 Months Ended
Share-based compensation (Details)	Jan. 01, 2026 shares	Jun. 27, 2022	Jul. 31, 2024 installment shares	Jun. 30, 2020 installment	May 31, 2019 shares	Jun. 30, 2026 installment shares	Dec. 31, 2025 shares
Stock option
Share-based compensation.
Shares outstanding						10,745,868	9,803,106
Employee Share Purchase Plan
Share-based compensation.
Number of ordinary shares reserved for issuance					215,000	2,437,671
Number of shares reserved for issuance	430,000
Percentage of annual increase in reserves on total number of ordinary shares outstanding					1.00%
Number of shares available for issuance					430,000
2024 Inducement Plan
Share-based compensation.
Number of ordinary shares reserved for issuance			1,500,000
Number of shares reserved for issuance						1,092,894
2024 Inducement Plan \| Stock option
Share-based compensation.
Contractual life			10 years
Shares outstanding						407,106
2024 Inducement Plan \| Stock option \| First anniversary
Share-based compensation.
Vesting Percentage			25.00%
2024 Inducement Plan \| Stock option \| Employee
Share-based compensation.
Vesting period			4 years
2024 Inducement Plan \| Stock option \| Employee \| Remaining equal installments
Share-based compensation.
Number of equal monthly installments for vesting remaining awards \| installment			36
2020 Plan
Share-based compensation.
Number of shares reserved for issuance						3,067,827
Percentage of annual increase in reserves on total number of ordinary shares outstanding		5.00%
Increase in number of ordinary shares reserved for future issuance	3,468,394
2020 Plan \| Stock option
Share-based compensation.
Contractual life				10 years
Shares outstanding						8,150,177
2020 Plan \| Stock option \| First anniversary
Share-based compensation.
Vesting Percentage				25.00%
2020 Plan \| Stock option \| Employee
Share-based compensation.
Vesting period				4 years
2020 Plan \| Stock option \| Employee \| Remaining equal installments
Share-based compensation.
Number of equal monthly installments for vesting remaining awards \| installment				36
2020 Plan \| Stock option \| Non-employee
Share-based compensation.
Vesting period				3 years
Service period						1 year
Number of equal quarterly installments for vesting remaining awards \| installment						4
2020 Plan \| Stock option three year vest \| Non-employee
Share-based compensation.
Number of equal annual installments \| installment				3		3
Service period						3 years
2020 Plan \| Restricted share units
Share-based compensation.
Vesting period						4 years
Shares outstanding						2,667,305
Right to receive upon vesting						1
2020 Plan \| Restricted share units \| First anniversary
Share-based compensation.
Vesting Percentage						25.00%
2020 Plan \| Restricted share units \| Remaining equal installments
Share-based compensation.
Number of equal quarterly installments for vesting remaining awards \| installment						12
2020 Plan \| Restricted share units \| Non-employee
Share-based compensation.
Service period						1 year
Number of quarterly installments \| installment						4
2019 Plan \| Stock option
Share-based compensation.
Contractual life						10 years
Shares outstanding						1,691,608
2019 Plan \| Stock option \| First anniversary
Share-based compensation.
Vesting Percentage						25.00%
2019 Plan \| Stock option \| Employee \| Remaining equal installments
Share-based compensation.
Number of equal monthly installments for vesting remaining awards \| installment						36
2019 Plan \| Minimum \| Stock option
Share-based compensation.
Vesting period						3 years
2019 Plan \| Maximum \| Stock option
Share-based compensation.
Vesting period						4 years