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Share-based compensation (Details)			1 Months Ended				12 Months Ended
Share-based compensation (Details)	Jan. 01, 2026 shares	Jun. 27, 2022	Jun. 30, 2025 shares	Jul. 31, 2024 M shares	Jun. 30, 2020 installment	May 31, 2019 shares	Dec. 31, 2025 installment shares	Dec. 31, 2024 shares
Stock option
Share-based compensation.
Shares outstanding							9,803,106	8,748,726
Employee Share Purchase Plan
Share-based compensation.
Number of ordinary shares reserved for issuance						215,000	2,007,671
Increase in number of ordinary shares reserved for future 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 shares reserved for issuance				1,500,000			925,581
2024 Inducement Plan \| Stock option
Share-based compensation.
Contractual life				10 years
Shares outstanding							574,419
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 \| M				36
2020 Plan
Share-based compensation.
Number of shares reserved for issuance							2,178,641
Increase in number of ordinary shares reserved for future issuance	3,468,394		1,300,000
Percentage of annual increase in reserves on total number of ordinary shares outstanding		5.00%
2020 Plan \| Stock option
Share-based compensation.
Contractual life					10 years
Shares outstanding							7,024,208
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 \| Restricted share units
Share-based compensation.
Right to receive upon vesting							1
Vesting period							4 years
Shares outstanding							1,644,421
Service period							1 year
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 \| Director [Member] \| Stock option
Share-based compensation.
Vesting period					3 years
Service period							1 year
Number of equal quarterly installments for vesting remaining awards \| installment							4
2020 Plan \| Director [Member] \| Stock option three year vest
Share-based compensation.
Service period							3 years
Number of equal annual installments \| installment					3		3
2020 Plan \| Director [Member] \| Restricted share units
Share-based compensation.
Number of quarterly installments \| installment							4
2019 Plan \| Stock option
Share-based compensation.
Contractual life							10 years
Shares outstanding							1,699,408
2019 Plan \| Minimum \| Stock option
Share-based compensation.
Vesting period							3 years
2019 Plan \| Maximum \| Stock option
Share-based compensation.
Vesting period							4 years
Pre-IPO Share Options and restricted shares \| Stock option \| First anniversary
Share-based compensation.
Vesting Percentage							25.00%
Pre-IPO Share Options and restricted shares \| Stock option \| Employee \| Remaining equal installments
Share-based compensation.
Number of equal monthly installments for vesting remaining awards \| installment							36