8. Share-based compensation

Employee incentive pool

2024 Inducement Plan

In July 2024, the Company’s board of directors approved the 2024 Inducement Plan. The 2024 Inducement Plan allows for the granting of nonqualified share options, RSUs, and other equity awards under the plan to persons not previously an employee or director of the Company, or following a bona fide period of non-employment, as an inducement material to such persons entering into employment with the Company. Share options granted under the 2024 Inducement Plan have a 10-year contractual life and generally vest over a four-year service period with 25% of the award vesting on the first anniversary of the vesting commencement date and the balance thereafter in 36 equal monthly installments. In the event of a Change in Control of the Company, as defined in the 2024 Inducement Plan, any outstanding awards under the 2024 Inducement Plan will vest in full immediately prior to such change of control.

The Company initially reserved 1,500,000 of its ordinary shares, or the equivalent number of ADSs, for the issuance of awards under the 2024 Inducement Plan. As of December 31, 2025, there were 925,581 shares available for future issuance under the 2024 Inducement Plan.

As of December 31, 2025, there were options to purchase 574,419 shares outstanding under the 2024 Inducement Plan.

2020 Equity Incentive Plan

In June 2020, the Company’s shareholders first approved the 2020 Plan, under which the Company may grant market value options, market value stock appreciation rights or restricted shares, RSUs, performance RSUs and other share-based awards to the Company’s employees. The Company’s non-employee directors and consultants are eligible to receive awards under the 2020 Non-Employee Sub-Plan to the 2020 Plan. All awards under the 2020 Plan, including the

2020 Non-Employee Sub-Plan, will be set forth in award agreements, which will detail the terms and conditions of awards, including any applicable vesting and payment terms, change of control provisions and post-termination exercise limitations. In the event of a change of control of the Company, as defined in the 2020 Plan, any outstanding awards under the 2020 Plan will vest in full immediately prior to such change of control.

The ordinary shares reserved for future issuance under the 2020 Plan includes shares subject to options that were granted under the Company’s 2019 Share Option Plan (the “2019 Plan”) and that were granted pursuant to option contracts granted prior to the Company’s IPO, in each case that expire, terminate, are forfeited or otherwise not issued from time to time, if any. Prior to June 2025, the number of ordinary shares reserved for issuance pursuant to the 2020 Plan automatically increased on the first day of January of each year, initially commencing on January 1, 2021 and continuing up to and including January 1, 2032, in an amount equal to 5% of the total number of the Company’s voting ordinary shares outstanding on the last day of the preceding year, or a lesser number of shares determined by the Company’s board of directors (the “Evergreen Increase”). In June 2025, the Company’s shareholders approved Amendment No. 1 to the 2020 Plan which (i) amended the calculation of the Evergreen Increase to capture the Company’s total issued share capital in order to treat non-voting ordinary shares the same as voting ordinary shares, and (ii) increased the number of ordinary shares reserved for future issuance by 1,300,000. As of December 31, 2025, there were 2,178,641 shares available for issuance under the 2020 Plan. The number of shares reserved for issuance under the 2020 Plan was increased by 3,468,394 shares effective January 1, 2026.

Share options granted under the 2020 Plan have a 10-year contractual life, and generally vest over either a three-year service period in three equal annual installments for new non-employee director grants, or a four-year service period with 25% of the award vesting on the first anniversary of the vesting commencement date and the balance thereafter in 36 equal monthly installments for employees and consultants. Certain options granted to the Company’s non-employee directors vest over a one-year service period in four equal quarterly installments.

The Company grants RSUs to non-employee directors, consultants and certain employees under the 2020 Plan. Each RSU represents the right to receive one of the Company’s ordinary shares upon vesting. RSUs granted to employees and consultants vest over a four-year service period with 25% of the award vesting on the first anniversary of the vesting commencement date and the remaining RSUs vesting in 12 equal quarterly installments. Certain RSUs granted to the Company’s non-employee directors either vest over a three-year service period in three equal annual installments for new non-employee director grants or over a one-year service period in four equal quarterly installments. The Company may also, in its sole discretion, provide for deferred settlement of RSUs granted to the Company’s non-employee directors.

As of December 31, 2025, there were options to purchase 7,024,208 shares and RSUs for 1,644,421 shares outstanding under the 2020 Plan.

2019 Share Option Plan

In May 2019, the Company adopted the 2019 Plan, which became effective in conjunction with the IPO. As of December 31, 2025, there were 1,699,408 options to purchase ordinary shares outstanding under the 2019 Plan. In conjunction with the adoption of the 2020 Plan, all shares available for future issuance under the 2019 Plan as of June 29, 2020 became available for issuance under the 2020 Plan and the Company ceased making awards under the 2019 Plan. The 2020 Plan is the successor of the 2019 Plan.

Share options previously issued under the 2019 Plan have a 10-year contractual life, and generally either vest monthly over a three-year service period, or over a four-year service period with 25% of the award vesting on the first anniversary of the commencement date and the balance thereafter in 36 equal monthly installments. Certain awards granted to the Company’s non-employee directors were fully vested on the date of grant. The exercise price of share options issued under the 2019 Plan is not less than the fair value of ordinary shares as of the date of grant.

Employee Share Purchase Plan (“ESPP”)

In May 2019, the Company adopted the ESPP, which became effective in conjunction with the IPO. The Company initially reserved 215,000 ordinary shares for future issuance under this plan. The ESPP provides that the number of shares reserved and available for issuance will automatically increase each January 1, beginning on January 1, 2020 and each January 1 thereafter through January 1, 2029, by the lower of (i) 1% of the outstanding number of ordinary shares on the immediately preceding December 31; (ii) 430,000 ordinary shares or (iii) such lesser number of shares as determined by the Compensation Committee. The number of shares reserved under the ESPP is subject to adjustment in the event of a split-up, share dividend or other change in the Company’s capitalization. As of December 31, 2025, the total number of shares available for issuance under the ESPP was 2,007,671 shares. The number of shares reserved for issuance under the ESPP was increased by 430,000 shares effective January 1, 2026. As of December 31, 2025, there have been no offering periods to employees under ESPP.

Share-based compensation

The Company recorded share-based compensation expense in the following expense categories of its consolidated statements of operations and comprehensive loss (in thousands):

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Share options

The following table summarizes the Company’s option activity since December 31, 2024:

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The weighted average grant-date fair value of share options granted during the years ended December 31, 2025, 2024 and 2023 was $8.47 per share, $13.52 per share and $19.36 per share, respectively.

The aggregate intrinsic value of share options is calculated as the difference between the exercise price of the share options and the fair value of the Company’s ordinary shares. The aggregate intrinsic value of share options exercised during the years ended December 31, 2025, 2024 and 2023 was $0.1 million, $5.1 million and $0.5 million, respectively.

For the years ended December 31, 2025, 2024 and 2023, the Company recorded share-based compensation expense for share options granted of $28.2 million, $30.2 million and $27.0 million, respectively.

The following table presents, on a weighted average basis, the assumptions used in the Black-Scholes option-pricing model to determine the fair value of share options granted to employees and directors:

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As of December 31, 2025, total unrecognized compensation expense related to the share options was $29.3 million, which is expected to be recognized over a weighted average period of 2.2 years.

Restricted share units

The following table summarizes the Company’s RSU activity under the 2020 Plan since December 31, 2024:

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The fair value of RSUs that vested during the years ended December 31, 2025, 2024 and 2023 was $3.7 million, $3.8 million and $3.0 million, respectively.

Total share-based compensation expense for RSUs granted for the years ended December 31, 2025, 2024 and 2023 was $11.3 million, $7.9 million and $5.5 million, respectively. As of December 31, 2025, the total unrecognized compensation expense related to RSUs was $16.8 million, which is expected to be recognized over a weighted-average period of 2.6 years.

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