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Number of shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Share-based compensation (Details)	1 Months Ended			9 Months Ended
Share-based compensation (Details)	Jul. 31, 2024 installment shares	Jun. 30, 2020 installment shares	May 31, 2019 shares	Sep. 30, 2024 installment shares	Jan. 01, 2024 shares	Dec. 31, 2023 shares	Jun. 27, 2022 shares
Stock option
Share-based compensation.
Shares outstanding				8,856,901		7,469,527
Employee Share Purchase Plan
Share-based compensation.
Number of shares reserved for issuance					377,258
Percentage of annual increase in reserves on total number of ordinary shares outstanding			1.00%
Number of ordinary shares reserved for issuance			215,000	1,577,671
Number of shares available for issuance			430,000
2020 Plan
Share-based compensation.
Number of shares reserved for issuance		4,773,557		156,582	1,886,294		750,000
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				6,457,155
2020 Plan \| Stock option \| Non-employee Director
Share-based compensation.
Vesting period		3 years
Number of equal quarterly installments for vesting remaining awards \| installment				4
Service period				1 year
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 three year vest \| Non-employee Director
Share-based compensation.
Number of equal annual installments \| installment				3
Service period				3 years
2020 Plan \| Restricted share units
Share-based compensation.
Vesting period				4 years
Right to receive upon vesting				1
RSUs outstanding under the 2020 Plan				812,426
2020 Plan \| Restricted share units \| Non-employee Director
Share-based compensation.
Service period				1 year
Number of quarterly installments \| installment				4
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
2019 Plan \| Stock option
Share-based compensation.
Contractual life				10 years
Shares outstanding				1,777,911
2019 Plan \| Minimum \| Stock option
Share-based compensation.
Vesting period				3 years
2019 Plan \| Maximum \| Stock option
Share-based compensation.
Vesting period				4 years
2024 Inducement Plan
Share-based compensation.
Number of shares reserved for issuance	1,500,000			1,399,300
2024 Inducement Plan \| Stock option
Share-based compensation.
Contractual life	10 years
Shares outstanding				100,700
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
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