8.           Share-Based Compensation

The Company maintains several equity compensation plans, including the 2018 Incentive Award Plan (the “2018 Plan”) and the 2018 Employee Share Purchase Plan (the “2018 ESPP”). Upon the effectiveness of the 2018 Plan, the Company ceased granting awards under its 2015 Equity Incentive Plan (as amended, the “2015 Plan” and together with the 2018 Plan, the “Plans”).

2015 Plan

As of June 30, 2026, there were 77,296 Class A ordinary shares reserved for issuance pursuant to outstanding awards under the 2015 Plan that were granted prior to the effectiveness of the 2018 Plan.

2018 Plan

The 2018 Plan provides for the grant of incentive share options, nonqualified share options, share appreciation rights, restricted shares, dividend equivalents, restricted share units (“RSUs”), PSUs (as defined below) and other share- or cash- based awards. Pursuant to the 2018 Plan’s evergreen provision, the number of shares available for future issuance under the 2018 Plan, as of January 1, 2026, increased by 3,051,742 Class A ordinary shares. As of June 30, 2026, 7,845,077 shares remained available for future grant under the 2018 Plan.

2018 ESPP

In December 2025, the Company’s board of directors approved an increase, as of January 1, 2026, of 110,000 Class A ordinary shares under the 2018 ESPP. As of June 30, 2026, 765,514 Class A ordinary shares were available for future issuance under the 2018 ESPP.

Restricted Share Units

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The Company grants RSUs with service conditions to eligible employees as part of its equity incentive compensation. Such RSUs typically vest 25% on each of the first, second, third and fourth anniversaries of the date of grant, subject to continued employment through such dates.

Market and Performance-Based Share Units

In 2024, the Company began periodically granting performance-based restricted share units to certain employees under the 2018 Plan that are earned based upon (i) the achievement of certain specified ARCALYST revenue targets (“Revenue PSUs”) and (ii) the Company’s total shareholder return (“TSR”) relative to the TSR of each member of a specified peer group (“TSR PSUs”). The TSR PSUs and Revenue PSUs are subject to a three-year service period.

In addition, the Company from time-to-time grants performance-based restricted share units to certain eligible employees pursuant to the 2018 Plan that are earned based upon certain development and regulatory milestones (“Development PSUs” and, together with the Revenue PSUs and TSR PSUs, “PSUs”). The Company’s currently outstanding Development PSUs are subject to earnout percentages based upon the date of applicable milestone achievement.

Performance Share Options

Beginning in the second quarter of 2025, the Company began granting performance share options (“PSOs”) to certain eligible employees pursuant to the 2018 Plan representing the right to purchase shares of the Company’s Class A ordinary shares. Such PSOs vest, if at all, upon the achievement of certain specified development and regulatory milestones and are subject to earnout percentages based upon the date of applicable milestone achievement.

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The following table summarizes RSU and PSU activity for the six months ended June 30, 2026:

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The following table summarizes share options and PSO activity for the six months ended June 30, 2026:

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As of June 30, 2026, total unrecognized compensation cost related to RSUs, Revenue PSUs, TSR PSUs, and share options was $122,664 which is expected to be recognized over a weighted average remaining period of 2.41 years. As of June 30, 2026, total unrecognized compensation cost related to outstanding Development PSUs and PSOs was $9,506 which will be recognized when the applicable milestones are deemed probable of achievement through the date the awards vest with a cumulative catch-up.

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Share-Based Compensation

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Share-based compensation expense was classified in the condensed consolidated statements of operations and comprehensive income as follows:

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