Zymeworks Inc

Discussion of Executive Compensation Practices

This section describes our executive compensation philosophy and how we implemented it through our 2023 compensation program for our named executive officers. The named executive officers for 2023 are:

•Kenneth Galbraith, Chief Executive Officer and Chair of the Board of Directors;

•Christopher Astle, Ph.D., Senior Vice President and Chief Financial Officer;

•Paul Moore, Ph.D., Chief Scientific Officer; and

•Neil Klompas, CPA, CA, our former President and Chief Operating Officer.

This discussion contains forward-looking statements that are based on our current plans, considerations, expectations and projections regarding future compensation programs. Actual compensation programs adopted in the future may differ materially from the various planned programs summarized in this discussion.

In the paragraphs that follow, we provide an overview and analysis of our compensation program and policies, the material compensation decisions we have made under those programs and policies, and the material factors that we considered in making those decisions.

2023 Advisory Vote on Executive Compensation

At our 2023 annual general meeting, we conducted an advisory vote on named executive officer compensation. At that meeting, 74.71% of the votes cast on the advisory vote proposal were supportive of our named executive officer compensation program as disclosed in our 2023 proxy statement. Our next advisory vote on named executive officer compensation will be held at our 2024 annual general meeting.

The compensation committee reviewed the advisory vote results in the context of our overall compensation philosophy and programs, and based on the level of support, determined that no significant changes to our compensation policies and programs were necessary. The compensation committee will continue to consider the results from future stockholder advisory votes on named executive officer compensation and other relevant market developments affecting named executive officer compensation in order to determine whether any subsequent changes to our named executive officer compensation programs and policies would be warranted to reflect any stockholder concerns reflected in those advisory votes or to address market developments.

Overview of Compensation Program

Compensation Philosophy

The goal of our compensation program is to attract, retain and motivate our employees and executives, including our named executive officers. The compensation committee is responsible for setting our executive compensation and reviewing and approving, or recommending to the board of directors for approval, the Company’s annual corporate performance objectives applicable to executive and other Company bonus programs. In considering executive compensation, the compensation committee strives to ensure that our total compensation is competitive within the industry in which we operate and supports our overall strategy and corporate objectives. The combination of base salary, annual incentives and long-term incentives that we provide our executives is designed to accomplish this.

Compensation Objectives

The objectives of our executive compensation program are to:

•attract and retain highly qualified executive officers who have a history of proven success;

•align the interests of executive officers with our stockholders’ interests and with the execution of our business strategy;

•motivate and reward our executive officers through competitive pay practices and an appropriate mix of short- and long-term incentives;

•evaluate and reward executive performance on the basis of achievement of program development goals and key financial measurements which we believe closely correlate to long-term stockholder value; and

•tie compensation awards directly to program development goals and key financial measurements with evaluations based on achieving and overachieving predetermined objectives.

Role of the Compensation Committee

During 2023, the compensation committee’s work included the following:

•Competitive Compensation Review – The compensation committee reviewed compensation practices and policies with respect to our executives against Zymeworks’ peer group of companies (as further described below), in order to allow us to place our compensation practices for these positions in a market context. This reference exercise included a review of base salary, total cash compensation and total direct compensation.

•Executive Compensation – The compensation committee reviewed the corporate goals and objectives applicable to the compensation of the Company’s executives and evaluated the executives’ performance in light of those goals and objectives. Based on this review and evaluation, the compensation committee approved the 2023 compensation for the Company’s executives, including each of the named executive officers. In addition, the compensation committee considered and approved the separation and transition arrangements related to Mr. Klompas.

•Short- and Long-Term Incentive Plans – The compensation committee administers the Company’s incentive compensation plans and equity-based plans with respect to the Company’s executives, including the named executive officers.

•Succession Planning – The compensation committee reviewed the succession plan for the Chief Executive Officer and other executive officers.

In reaching its decisions, the compensation committee may consider input from management and other factors that the compensation committee considers appropriate. Decisions made by the compensation committee are the responsibility of the compensation committee and may reflect factors and considerations other than the information and/or recommendations provided by management.

Independent Compensation Consultant

In 2023, the compensation committee retained the Human Capital Solutions practice at Aon plc, as an independent consultant to the compensation committee to conduct competitive reviews and assessments of Zymeworks’ executive compensation program and recommend go-forward strategies. The compensation committee made the decision to retain Aon in its sole discretion and was directly responsible for the appointment, compensation and oversight of Aon’s work. The compensation committee is involved in and approves the adoption of the following procedures during Aon’s assessments:

•establishing the public company peer group used in the executive compensation assessment;

•reviewing the detailed assessment of Zymeworks’ executive compensation program versus the market;

•reviewing and approving executive pay mix;

•reviewing the assessment of Zymeworks’ board of directors compensation program versus the market; and

•reviewing and approving the non-executive equity compensation program.

The compensation committee utilizes these strategies when contemplating future executive compensation matters.

In 2023, Aon was retained to review the salaries, bonuses and equity plan levels and participation of executive employees, as well as equity plan levels and participation of employees below the executive level. Zymeworks’ management did not make or recommend such engagements and all such other services were approved by the compensation committee. Except as discussed below, Aon did not perform other services to the Company other than as a compensation consultant. The compensation committee determined Aon to be independent after evaluating the factors required under the applicable listing standard.

Aon received $244,996 in fees in 2023 for services related to determining or recommending the amount or form of executive and non-employee director compensation. Separately, management engaged Aon to perform unrelated broad-based compensation services and risk brokerage services (which included global risk in Canada and the United States), for which Aon was paid $328,913. The compensation committee was informed about these services.

Peer Companies and Use of Market Data

We compare our executive compensation program to those of a group of peer companies (North American biotechnology companies of a similar size and stage of development). The first step in the process is that the compensation committee, with the support of Aon and management, reviews trends in biotechnology compensation practices and reviews and approves the list of peer companies used for benchmarking. As part of its analysis for 2023, Aon collected and analyzed compensation information from a comparative group of biotechnology companies, or peer group, approved by the compensation committee. The compensation committee evaluates the criteria used in establishing the peer group at least annually. The compensation committee seeks input from management in addition to Aon to ensure the peer group is consistent with our current business objectives and strategy.

The list of peer companies is approved based on various factors including industry classification, market capitalization, headcount and stage of development. In August 2022, with assistance from Aon, the compensation committee approved a peer group consisting of publicly traded, pre-commercial biopharmaceutical companies:

•with an emphasis on oncology companies and a focus on companies in Phase 2 and Phase 3 clinical trials;

•with market capitalizations generally between $150 million and $1.2 billion (based on the Company’s then-current 30-day average market capitalization of approximately $400 million);

•with generally between 100 and 900 employees;

•that are located in Canada and the United States, with a focus on companies headquartered in biotechnology hub markets; and

•preference for companies that have gone public in approximately the last five years (but continue to de-emphasize initial public offering date as a primary selection criteria).

Based on these criteria, in August 2022, the compensation committee approved the following peer group set forth below and used this peer group to inform compensation decisions for 2023:

(1) Added to the peer group in August 2022. The following companies were deleted from the peer group approved in August 2022: Allogene Therapeutics, Inc., Athira Pharma, Inc. and Harpoon Therapeutics, Inc.

Our compensation committee uses comparative data from our peer group as a reference when setting and adjusting executive compensation, but it does not target our overall program or any particular element of compensation to be at a particular percentile compared to our peers. Rather, our compensation committee uses a range of peer group data for each executive position for which data is available, along with an assessment of each executive’s performance, criticality and tenure, to ensure that our executive compensation program and its constituent elements are and remain competitive in relation to our peers.

Components of Compensation Package

In 2023, our executive compensation program consisted of three major components:

•base salary;

•annual cash bonuses based on a comparison of corporate performance to pre-set goals and objectives; and

•long-term incentives, which in 2023, consisted of grants of stock options and restricted stock units.

In making 2023 compensation decisions, our compensation committee believed that each component of executive compensation must be evaluated and determined with reference to competitive market data, individual and Company-wide performance, our recruiting and retention goals, internal equity and consistency, and other information it deems relevant. As it evaluated executive compensation in 2023, the compensation committee believed that in the biopharmaceutical/biotechnology industry, long-term incentives such as stock options and restricted stock units are a primary motivator in attracting and retaining executives, in addition to salary and cash incentive bonuses.

The primary components of our 2023 executive compensation program are described in more detail below.

Base Salary Annual base salary is designed to provide a competitive fixed rate of pay recognizing different levels of responsibility and performance within Zymeworks. This compensation component helps us to attract and retain highly qualified executives who have a history of proven success. In determining whether to increase the base salary for a particular executive, our compensation committee in discussions with our Chief Executive Officer (for executives other than the Chief Executive Officer) considers a variety of factors, including performance, length of service and criticality of role. The determination of base salary affects the amount of an executive’s cash bonus. The table below shows the base salaries of our named executive officers for 2023:

(1) Mr. Galbraith has served as our Chief Executive Officer and Chair of our board of directors since January 2022. In addition, Mr. Galbraith has served as our President since June 2023 and previously served as our President from January 2022 to August 2022.

(2) Mr. Klompas resigned from the positions of President and Chief Operating Officer effective June 2023.

Cash Bonus

The cash bonus component is designed to provide our named executive officers with annual cash incentive awards based on achievement of certain goals and objectives. The awards represent pay at risk – they result in payment only if and to the extent certain goals and objectives are met – and do not affect decisions regarding other components of compensation. This compensation component motivates and rewards our named executive officers for outstanding performance.

Annual cash incentive compensation for our named executive officers is paid pursuant to the Company’s Executive Incentive Compensation Plan, which provides the compensation committee discretion to make changes to performance targets and bonus targets, to decrease, increase or eliminate bonuses and to change other terms and conditions related to annual incentive compensation, in each case as the compensation committee deems appropriate to meet the overarching retention and incentive goals associated with our executive bonus program.

Named executive officers are eligible to receive an amount targeted at a pre-determined percentage of their base salary established at the beginning of each year. In January 2023, the compensation committee set annual target bonuses for each of our named executive officers as follows:

(1) Mr. Galbraith has served as our Chief Executive Officer and Chair of our board of directors since January 2022. In addition, Mr. Galbraith has served as our President since June 2023 and previously served as our President from January 2022 to August 2022.

(2) The compensation committee assigned a target bonus percentage for Mr. Klompas in January 2023. However, Mr. Klompas resigned from the positions of President and Chief Operating Officer effective June 2023. Pursuant to the Klompas Separation Agreement, Mr. Klompas was not eligible for any annual performance bonus with respect to the Company’s 2023 fiscal year. For more information regarding the Klompas Separation Agreement, see the section titled “Executive Employment Arrangements and Potential Payments upon Termination or Change in Control—Executive Employment Arrangements.”

At the beginning of each year, the compensation committee approves, or recommends that the board of directors approve, performance targets that are tied to the level of achievement of corporate and/or individual goals, and the compensation committee approves the weighting assigned to each goal. For 2023, the corporate and individual weighting was 100% corporate and 0% individual for all named executive officers. Achievement of corporate goals was a precondition for payment of bonuses with respect to 2023. Our compensation committee believed that this mix was appropriate in order to incentivize our management team to achieve our key corporate objectives.

After the end of the year, the compensation committee determines the performance bonus payable to each named executive officer based on the results achieved as compared to the performance targets established for a particular year. Depending on level of achievement, named executive officers may earn up to 150% of their respective target bonuses. There is no minimum bonus payable.

2023 Company Corporate Goals and Achievement

In January 2023, the board of directors approved corporate goals that were grouped into six main categories: (i) zanidatamab via the Jazz Partnership, (ii) zanidatamab via the BeiGene Partnership, (iii) zanidatamab zovodotin (ZW49), (iv) Early R&D (ZW171, ZW191 and emerging pipeline), (v) Platforms and Legacy Partnerships and (vi) Financial. In September 2023, the compensation committee updated certain of the corporate goals established at the beginning of the year related to zanidatamab zovodotin to align with our revised strategy with respect to zanidatamab zovodotin.

In January 2024, the compensation committee reviewed our performance against the corporate goals under the 2023 bonus plan, as revised in September 2023, and determined that these goals were achieved at the 87.25% level. Additional detail on these goals and the assessed achievement is set forth in the table below:

Given the Company’s strong performance against its 2023 corporate goals, the compensation committee determined that these goals were achieved at the 87.25% level and approved 2023 bonuses for our named executive officers as follows:

(1) Bonus amounts for all named executive officers are determined in U.S. dollars, and the table above reflects this determination in U.S. dollars. However, the 2023 bonuses for Dr. Astle and Dr. Moore were paid in Canadian dollars and the 2023 bonus for Mr. Galbraith was paid in British pounds, based on conversion rates in effect at the time of payment.

(2) Mr. Klompas resigned from the positions of President and Chief Operating Officer effective June 2023, and therefore did not receive a bonus with respect to 2023.

Long-Term Incentives

Our Amended and Restated Stock Option and Equity Compensation Plan (the “Equity Compensation Plan”) authorizes us to make grants to eligible recipients of stock options, restricted stock, restricted stock units and other share-based awards, to attract, retain, motivate and reward qualified directors and employees and to enable and encourage such directors and employees to acquire shares of common stock as long-term investments.

In January 2023, the Company granted a mix of stock options and restricted stock units to our named executive officers. The compensation committee believes this approach aligns the interests of our executives (including those of our named executive officers) with our stockholders’ interests by rewarding for improvements in stock price over a period of time. The Company issues stock options and restricted stock units to reward for future performance and appreciation. Because stock options only have value if our stock price increases relative to the stock option’s exercise price, we consider them to be an important performance-based tool that encourages our named executive officers to focus on driving increases to stockholder value. Restricted stock units play an important role in our executive compensation program because they provide some value even during periods of stock price or market volatilities, provide retention incentives during the vesting period, and reinforce a culture of ownership. By granting restricted stock units, the Company can also reduce the dilutive effect of the equity incentive awards in the form of stock options, which benefits our stockholders over time. In addition, the vesting feature of our stock awards contributes to executive retention by providing an incentive to our executives to remain employed by us during the vesting period. For 2023, we determined that annual grants to our named executive officers in the form of a 50/50 value mix of stock options and restricted stock units was most appropriate to reflect the continued change in the market and the evolution of our compensation program away from an options-only approach. The compensation committee evaluates the long-term incentive programs for each year, and the appropriate mix of equity awards to grant to our executive officers for the applicable year. In future years, the compensation committee may approve a different mix of equity awards if it determines necessary or appropriate to achieve our compensation objectives.

The option exercise price may not be less than the closing price of our common stock on the date of grant. For the 2023 stock option grants to our named executive officers, 25% of the granted options is scheduled to vest on the first anniversary of grant date (subject to continued service and any applicable acceleration of vesting provisions in their employment agreements, as described below). On the last day of each month thereafter, a further 1/36 th of the total number of remaining granted options is scheduled to vest.

Each restricted stock unit represents the right to receive one share of our common stock upon vesting of that unit, without the payment of an exercise price or other cash consideration for the issued shares of common stock. For the 2023 restricted stock unit grants to our named executive officers, 1/3 rd of the restricted stock units are scheduled to vest on each anniversary of the grant date (subject to the named executive officer’s continued service and subject to any applicable acceleration provisions in the Equity Compensation Plan or in the named executive officer’s employment agreement.

The following table shows information regarding stock option and restricted stock unit grants to each of our named executive officers made during the year ended December 31, 2023:

(1) Restricted stock units vest in three equal annual installments beginning on January 5, 2024, subject to the optionee’s continued service through each vesting date and any applicable acceleration of vesting provisions described under the section below entitled “Executive Employment Arrangements and Potential Payments upon Termination or Change in Control.”

(2) Options vest and become exercisable with respect to (i) 25% of the underlying shares one year after the grant date and (ii) the remainder of the underlying shares in 36 equal monthly installments following the first anniversary of the date of grant, subject to the optionee’s continued service through each vesting date and any applicable acceleration of vesting provisions described under the section below entitled “Executive Employment Arrangements and Potential Payments upon Termination or Change in Control.”

(3) The exercise price of the stock options is the closing price of the Company’s stock on the Nasdaq on the grant date.

(4) The amounts set forth in this column reflect the grant date fair value for restricted stock unit awards and stock option awards computed in accordance with Financial Accounting Standards Board Accounting Standards Codification Topic 718, Compensation – Stock Compensation. See Note 2 to the “Notes to Consolidated Financial Statements – Summary of Significant Accounting Policies – Stock-Based Compensation” and Note 10(e) “Notes to Consolidated Financial Statements – Stockholders’ Equity-Stock Based Compensation” included in this Annual Report on Form 10-K for our year ended December 31, 2023.

Previous grants are taken into account when considering new option and restricted stock unit grants, as well as other factors such as market data, retention and incentive considerations, internal equity, Company performance and prior and expected future individual contributions. Decisions regarding long-term incentives do not affect decisions regarding other components of compensation.

Benefits and Perquisites

Other compensation to our named executive officers primarily consists of participation in our broad-based employee benefit plans. Named executive officers are eligible to participate in all our employee benefit plans, in each case on the same basis as other employees in the entity in which they are employed, including a retirement savings plan for those employed in Canada, a 401(k) plan for those employed in the United States, and pension plans for those employed in Ireland and the United Kingdom. Our named executive officers also are eligible to participate in our employee stock purchase plan on the same terms as our other eligible employees.

Currently, we do not view perquisites or other personal benefits as a material component of our executive compensation program. However, we do provide certain perquisites to our named executive officers in situations where we believe it is appropriate to assist an individual in the performance of his or her duties, to make them more efficient and effective, and for recruitment and retention purposes.

In addition, consistent with our philosophy regarding personal benefits, and as further described in “Executive Compensation—Executive Employment Arrangements and Potential Payments upon Termination or Change in Control,” to encourage and facilitate Dr. Moore’s relocation to Canada, we provide him with certain reimbursements for relocation expenses, as well as a gross-up to make sure such payments are tax neutral to him, tax equalization payments to neutralize any increase in his taxes as a result of his relocation, and tax preparation assistance for two years following his relocation. The compensation committee believes these benefits were appropriate to enable a smooth relocation for Dr. Moore and to allow him to keep his focus on the business rather than on the costs and burdens of the relocation.

Similarly, in November 2022, we amended Dr. Astle’s employment agreement to provide certain corporate housing benefits based on need (as determined in the Company’s discretion) in the Vancouver, British Columbia metropolitan area. In addition to the corporate housing benefits, we provided for a gross-up to Dr. Astle for the impact of any tax withholding related to the corporate housing benefits. The compensation committee believes that these corporate housing benefits were important to allow Dr. Astle to be on-site at our offices in Vancouver as needed, increase his ability to work efficiently, and focus his efforts on the business rather than travel and housing considerations.

We also provide certain personal benefits to Mr. Galbraith, which were negotiated as part of Mr. Galbraith’s initial January 2022 employment agreement and subsequent amendments, including the most recent amendment in January 2024. These benefits were provided in order to induce him to initially join and later to remain with the Company and to increase his ability to work efficiently. These benefits include certain housing, travel, relocation, and certain tax equalization and gross-up benefits, as described in “Executive Compensation – Executive Employment Arrangements and Potential Payments upon Termination or Change in Control.” In late 2022 and again in January 2024, we amended Mr. Galbraith’s employment agreement to extend the time period for certain benefits, as described in “Executive Compensation – Executive Employment Arrangements and Potential Payments upon Termination or Change in Control.” The compensation committee approved the extension of these benefits as it believed that doing so would assist Mr. Galbraith in the continued performance of his duties and continue to aid in his efficiency.

In the future, we may continue to provide perquisites or other personal benefits in circumstances where we believe it is appropriate to assist an individual named executive officer in the performance of his or her duties, to make him or her more efficient and effective, and for recruitment, motivation or retention purposes.

Anti-Hedging Policy and Clawback Policy

Under the terms of our Insider Trading Policy, all directors, officers, employees, as well as any other personnel that we determine should be subject to our Insider Trading Policy (such as contractors and consultants), any person or entity an insider controls, exercises substantial influence over, serves as a trustee or in a similar fiduciary capacity of or is otherwise involved with, in connection with securities trading or investment decisions and an insider’s spouse, partner, parents, children, dependents and other family members or roommates, are prohibited from purchasing financial instruments (including, for greater certainty, prepaid variable forward contracts, equity swaps, collars, or units of exchange funds) designed to hedge or offset a decrease in the market value of our securities.

In November 2023, we adopted a clawback policy in accordance with the SEC and Nasdaq requirements under the Dodd-Frank Wall Street Reform and Consumer Protection Act. This policy provides for the non-discretionary recovery of excess incentive-based compensation from current and former executive officers in the event of an accounting restatement, whether or not the executive officer was at fault for the restatement, in accordance with the SEC and Nasdaq requirements.

In addition, as a public company subject to Section 304 of the Sarbanes-Oxley Act of 2002, if we are required to prepare an accounting restatement due to our material noncompliance, as a result of misconduct, with any financial reporting requirement under the securities laws, our chief executive officer and chief financial officer may be legally required to reimburse us for any bonus or incentive-based or equity-based compensation they received from us during the 12-month period following the first public issuance or filing with the SEC of the financial document incorporating such financial reporting requirement, as well as profits realized from the sale of securities during that 12-month period.

Potential Payments upon Termination or Change in Control

Certain of our executives, including each of our named executive officers who remain current employees, are parties to employment agreements with us which set forth conditions of employment and the payments that will be made upon termination of their employment. Additional discussion of the employment agreements with our named executive officers is set forth below under “Executive Compensation—Executive Employment Arrangements and Potential Payments upon Termination or Change in Control.” We believe that these protections are necessary to provide our valuable named executive officers with incentives to forego other employment opportunities and to maintain continued focus and dedication to their responsibilities to maximize stockholder value, including if there is a potential transaction that could involve a change in control, without undue concern that the officer will be terminated and lose his or her income and benefits. We believe the level of severance and change in control benefits provided is appropriate and is necessary to attract and retain key employees.

In May 2023, in connection with Mr. Klompas’ cessation of employment with Zymeworks, we and Mr. Klompas entered into a separation agreement that provided for certain severance payments and benefits to Mr. Klompas in consideration for a release of claims in favor of us, effective June 2023. We believe that this separation arrangement was appropriate in light of Mr. Klompas’ past (and expected future) contributions to Zymeworks, and generally believe it is favorable to us to obtain a release of claims even in the event of a mutual agreement to separate from employment. We also entered into a consulting service agreement with Mr. Klompas pursuant to which he assists us with certain transitional matters. We entered into the consulting service agreement in order to provide a smooth transition of Mr. Klompas’ duties and responsibilities and to allow us to benefit from his ongoing input and expertise on certain matters. Additional discussion of these arrangements is set forth below under “Executive Compensation—Executive Employment Arrangements and Potential Payments upon Termination or Change in Control.”

Summary Compensation Table

The following table presents the compensation awarded to, earned by or paid to each of our named executive officers for the years ended December 31, 2023 and December 31, 2022. We do not have non-qualified deferred compensation.

(1) Salary, non-equity incentive plan compensation (bonuses) and amounts in the “All Other Compensation” column for all named executive officers are determined in U.S. dollars. However, 2023 and 2022 cash compensation amounts for Mr. Klompas and Dr. Astle, and a portion of 2023 cash compensation amounts for Dr. Moore, were paid in Canadian dollars and have been converted to U.S. dollars for the purposes of the table. For 2023 and 2022, the U.S. dollar per Canadian dollar exchange rates used for such conversions were 0.7410 and 0.7685, which were the average annual Bank of Canada exchange rates for 2023 and 2022, respectively. Cash compensation amounts for Mr. Galbraith were paid in British pounds and have been converted to U.S. dollars for the purposes of the table. For 2023 and 2022 the U.S. dollar per British pound exchange rate used for such conversion were 1.2437 and 1.2354, which were the average annual Bank of Canada exchange rate for 2023 and 2022, respectively.

(2) The amounts set forth in these columns reflect the aggregate grant date fair value for restricted stock unit awards and option awards computed in accordance with Financial Accounting Standards Board Accounting Standards Codification Topic 718, Compensation – Stock Compensation. See Note 2 to the“Notes to Consolidated Financial Statements – Summary of Significant Accounting Policies – Stock-Based Compensation” and Note 10(e)“Notes to Consolidated Financial Statements – Shareholders’ Equity – Stock Based Compensation” included in this Annual Report on Form 10-K for our year ended December 31, 2023.

(3)The amounts reflect the dollar value of incentive bonuses paid in 2024 and 2023 for performance during 2023 and 2022, respectively, as discussed further above under “Executive Compensation – Components of Compensation Package – Cash Bonus.”

(4) Mr. Galbraith has served as our Chief Executive Officer and Chair of our board of directors since January 2022. In addition, Mr. Galbraith has served as our President since June 2023 and previously served as our President from January 2022 to August 2022.

(5) Of the total amount for 2023, (i) $53,260 represents accommodation benefits, (ii) $6,547 represents Company contributions to a defined contribution pension plan, (iii) $746 represents life insurance premiums through our group extended benefit plan, (iv) $17,593 represents airfare for immediate family members in accordance with the terms of Mr. Galbraith’s employment agreement, and (v) $11,000 represents an estimated tax equalization payment (which includes $6,000 for estimated tax gross-up) in connection with taxation attributable to the performance of work outside the United Kingdom.

(6) Of the total amount for 2022, (i) $45,724 represents accommodation benefits, (ii) $20,263 represents Company contributions to a defined contribution pension plan, (iii) $2,158 represents life insurance premiums through our group extended benefit plan, and (iv) $13,104 represents airfare for immediate family members in accordance with the terms of Mr. Galbraith’s employment agreement.

(7) Dr. Astle joined Zymeworks in April 2021 as Executive Director, Corporate and Commercial Finance and was promoted to Senior Vice President and Chief Financial Officer in February 2022.

(8) Of the total amount for 2023, (i) $131,229 represents accommodation benefits (which includes $61,021 for tax gross-up), (ii) $13,289 represents Company contributions to our registered retirement savings plan, and (iii) $2,712 represents life insurance premiums through our group extended benefit plan.

(9) Of the total amount for 2022, (i) $136,960 represents accommodation benefits (which includes $63,686 for tax gross-up), (ii) $21,525 represents Company contributions to our registered retirement savings plan, and (iii) $951 represents life insurance premiums through our group extended benefit plan.

(10) Dr. Moore has served as our Chief Scientific Officer since July 2022. Dr. Moore was not a named executive officer in 2022. As such, Dr. Moore’s compensation for 2022 is not included in the table above.

(11) Of the total amount for 2023, (i) $41,496 represents accommodation benefits, (ii) $163,115 represents relocation expenses (which includes $77,334 for tax gross-up), (iii) $19,800 represents Company contributions to our 401(k) plan, and (iv) $351 represents life insurance premiums through our group extended benefit plan.

(12) Mr. Klompas served as our Chief Operating Officer and Chief Financial Officer until February 2022, as our Chief Operating Officer from February 2022 until August 2022, and as our President and Chief Operating Officer from August 2022 to June 2023.

(13) Included in the total amount for 2023 is $54,942 which represents payment of accrued vacation.

(14) Of the total amount for 2023, (i) $990,970 represents severance payments and benefits under a separation agreement, (ii) $15,998 represents Company contributions to our registered retirement savings plan and, (iii) $833 represents life insurance premiums through our group extended benefit plan.

(15) Included in the total amount for 2022 is $47,624 which represents payment of accrued vacation.

(16) Of the total amount for 2022, (i) $23,004 represents Company contributions to our registered retirement savings plan and (ii) $874 represents life insurance premiums through our group extended benefit plan.

Outstanding Equity Awards at 2023 Year End

The following table lists all outstanding equity awards granted in Canadian dollars under our Second Amended and Restated Stock Option Plan, as amended (the “Original Plan”) and equity awards granted in U.S. dollars under the Equity Compensation Plan and our Inducement Stock Option and Equity Compensation Plan (the “Inducement Plan”) held by our named executive officers as of December 31, 2023:

(1) Options vest and become exercisable with respect to (i) 25% of the underlying shares one year after the grant date and (ii) the remainder of the underlying shares in 36 equal monthly installments following the first anniversary of the date of grant, subject to the optionee’s continued service through each vesting date and any applicable acceleration of vesting provisions described under the section below entitled “Executive Employment Arrangements and Potential Payments upon Termination or Change in Control.”

(2) Unless otherwise noted, restricted stock units vest in three equal annual installments on each of the first, second, and third anniversaries of the date of grant, subject to the holder’s continued service through each vesting date and any applicable acceleration of vesting provisions described under the section below entitled “Executive Employment Arrangements and Potential Payments upon Termination or Change in Control.”

(3) Market value of restricted stock units that have not vested is based on the closing price of the Company’s common shares on Nasdaq on December 29, 2023, which was $10.39 per share.

(4) These restricted stock units vest on the third anniversary of the date of grant, subject to the holder’s continued service. Pursuant to the terms of Mr. Galbraith’s grant agreement with respect to these restricted stock units, (i) if Mr. Galbraith’s employment is terminated by the Company without cause, 100% of the restricted stock units will fully vest, and (ii) if on or within twelve months following a change of control (as defined in Mr. Galbraith’s employment agreement) or within three months prior to a change of control, Mr. Galbraith’s employment with the Company terminates due to his resignation for good reason, 100% of the restricted stock units will fully vest, in each case of (i) and (ii) subject to Mr. Galbraith having entered into a valid and enforceable settlement agreement with the Company on terms satisfactory to the

Company. These restricted stock units also are subject to the applicable acceleration of vesting provisions described for Mr. Galbraith under the section below entitled “Executive Employment Arrangements and Potential Payments upon Termination or Change in Control.”

(5) These options were granted with exercise prices denominated in Canadian dollars. The U.S. dollar per Canadian dollar exchange rate used to convert option exercise price to U.S. dollars was 0.7410, which was the average annual Bank of Canada exchange rate for 2023.

Pension Benefits

We do not have any qualified or non-qualified defined benefit pension plans.

Non-qualified Deferred Compensation

We do not have any non-qualified defined contribution plans or other deferred compensation plans.

Executive Employment Arrangements and Potential Payments upon Termination or Change in Control

Executive Employment Arrangements

Key provisions of the employment agreements that were in effect as of December 31, 2023, for our named executive officers are described below.

Kenneth Galbraith. In connection with Mr. Galbraith’s appointment as President and Chief Executive Officer in January 2022, Mr. Galbraith entered into an employment agreement with us (the “Original Agreement”), on December 30, 2022 Zymeworks BC and Zymeworks Management Inc., our subsidiaries, and Mr. Galbraith entered into an amendment to the Original Agreement (the “First Amendment”), and on January 3, 2024, Zymeworks BC and Mr. Galbraith entered into a second amendment (the “Second Amendment” and the Original Agreement, as amended by the First Amendment and the Second Amendment, the “Galbraith Employment Agreement”). The Galbraith Employment Agreement does not have a specific term. The Second Amendment established Mr. Galbraith’s principal place of employment as the United Kingdom, or another location as agreed upon between the parties, which removes the requirement for Mr. Galbraith to relocate to Vancouver, British Columbia or Seattle, Washington, and incorporated certain extensions of compensation and benefit provisions, as described below.

Pursuant to the Galbraith Employment Agreement, Mr. Galbraith is entitled to the following compensation and benefits:

•An annual base salary of $600,000, with eligibility to earn an annual discretionary bonus of up to 60% of his annual base salary, based upon the achievement of certain Company goals determined by the board of directors. Mr. Galbraith’s current annual base salary is $655,000 and his target annual discretionary bonus remains at 60% of his annual base salary;

•Options, which were granted to Mr. Galbraith in 2022, to purchase 500,000 of our common shares at an exercise price per share equal to the fair market value on the date of grant (the “Inducement Options”). 25% of the Inducement Options vest and become exercisable on the one-year anniversary of the date of grant, and thereafter 1/36th of the remaining Inducement Options will vest on the last day of each month, until all of the Inducement Options have vested, subject to Mr. Galbraith’s continued service;

•Eligibility to participate in our employee benefit plans, policies and arrangements that, in the aggregate, are reasonably consistent with other executive officers generally, as well as reimbursement for certain fees and costs related to membership in certain professional associations and professional development;

•Enrollment in a qualifying pension scheme under the UK Pensions Act 2008;

•Prior to the Second Amendment, the Galbraith Employment Agreement provided for reimbursement of relocation expenses up to a maximum gross amount of $300,000, grossed up for the impact of any tax withholding, for reasonable moving expenses incurred by Mr. Galbraith and his immediate family during relocation from Mr. Galbraith’s primary residence to Vancouver, British Columbia or Seattle, Washington if he relocated on or before July 15, 2024 (under the Original Agreement, this related to a relocation within the first eighteen months of employment), with the total amount reimbursed under this provision required to be repaid if Mr. Galbraith’s employment had terminated within three years (two years under the Original Agreement) following the effective date of employment. The Second Amendment removed the requirement to relocate, and deleted this provision regarding relocation expenses;

•Temporary housing for Mr. Galbraith in Vancouver, British Columbia, grossed up for the impact of any tax withholding. The First Amendment had provided for this benefit through the earlier of Mr. Galbraith’s relocation or July 15, 2024, and under the Original Agreement, this was through the earlier of Mr. Galbraith’s relocation or the date that is 18 months following the effective date of employment;

•Reimbursement of reasonable travel and living expenses when traveling from his home to Vancouver, British Columbia or Seattle, Washington for his employment duties, as well as reimbursement or Company payment for reasonable airfare and lodging expenses for Mr. Galbraith and his immediate family for one trip per calendar year to Vancouver, British Columbia or Seattle, Washington, as applicable (under the Original Agreement, this related to trips that occurred prior to the end of 2023 under the Original Agreement, and under the First Amendment, to trips that occurred prior to the end of 2024);

•A tax equalization payment if Mr. Galbraith is subject to income taxation or other taxation outside of the United Kingdom during the period of his employment, grossed up for the impact of any tax withholding, and tax preparation services;

•If we terminate Mr. Galbraith’s employment during his first three years of employment, then Mr. Galbraith will be eligible to receive twelve months of notice or the equivalent of twelve months of base salary as of the date notice is given, or any combination thereof that totals twelve months of combined notice and base salary. Commencing in the fourth year of his employment, if we terminate Mr. Galbraith’s employment, Mr. Galbraith will be eligible to receive an additional one month of notice or the equivalent of one month of base salary as of the date notice is given, or any combination thereof, for each additional completed year of service, up to a total maximum of eighteen months. Mr. Galbraith will also be eligible for continuation of group health and dental benefits through the applicable notice period to the extent permitted by any applicable benefit plan;

•In the event of termination on death or disability, as defined in our long-term disability plan or policy then in effect with respect to him, Mr. Galbraith, or his estate, will receive (x) a lump sum payment equal to the difference between (1) eighteen months of base salary plus target annual cash bonus as of the date of death or disability and (2) the amount that Mr. Galbraith or his estate will receive as a result of death or disability under our applicable insurance policies in effect as of the date of termination, (y) group extended health and dental benefits continuation for his surviving family members for eighteen months (or lump sum payment for the premium costs of such benefits in lieu thereof), and (z) full vesting acceleration of all unvested and outstanding stock options or other equity grants made to Mr. Galbraith as of the date of death or disability;

•If Mr. Galbraith’s employment is terminated by us without cause on or within twelve months following, or within three months prior to, a change of control (as defined in the Galbraith Employment Agreement), Mr. Galbraith will be eligible to receive (x) a lump sum payment of eighteen months of base salary and 100% of target annual cash bonus as of the date of termination, (y) group extended health and dental benefits continuation as of the date of termination for eighteen months (or lump sum payment for the premium costs of such benefit plans in lieu thereof) and (z) full vesting acceleration of all unvested and outstanding stock options or other equity grants as of the date of termination. Such payments will be subject to Mr. Galbraith entering into a valid settlement agreement with us; and

•In addition, the Galbraith Employment Agreement requires Mr. Galbraith, among other things, not to compete, either directly or indirectly, with us while employed by us and for up to six months following the termination of his employment with us. The Galbraith Employment Agreement also requires Mr. Galbraith not to solicit our employees or consultants to terminate their relationship with us while he is employed by us and for up to one year following the termination of his employment with us.

On August 4, 2022, Mr. Galbraith ceased to serve in the role of our President, which role was then assumed by Mr. Klompas, and Mr. Galbraith continued in the role of Chair of the Board of Directors and Chief Executive Officer. Effective upon Mr. Klompas’ departure in June 2023, Mr. Galbraith was re-appointed as our President. The compensatory and other material terms of Mr. Galbraith’s employment with us were unchanged in connection with his re-appointment as our President.

Neil Klompas. On August 4, 2022, the board of directors appointed Mr. Klompas as our President, effective August 4, 2022. Mr. Klompas continued in the role of Chief Operating Officer following his appointment our President. The compensatory and other material terms of Mr. Klompas’ employment with us, described below, were unchanged in connection with his appointment as President. Effective June 30, 2023, Mr. Klompas stepped down as our President and Chief Operating Officer and separated from employment. In May 2023, in anticipation of Mr. Klompas’ departure, Zymeworks BC and Mr. Klompas entered into a separation agreement and release (the “Klompas Separation Agreement”) providing for certain benefits, including:

•A lump sum payment of $1,000,000, equivalent to twenty-four (24) months of his then-current base salary, which payment was subject to Mr. Klompas not being terminated for cause prior to the June 30, 2023 (Mr. Klompas was not terminated for cause prior to such date and therefore became entitled to this payment). Mr. Klompas was not eligible for any annual performance bonus with respect to our 2023 fiscal year;

•Eligibility for Mr. Klompas and his spouse to participate in our employee benefit plans for the lesser of (a) twenty-four (24) months following June 30, 2023 and (b) the date of enrollment in the benefit plans of a new employer;

•Payments of $7,500 for professional development and continuing educational courses and $2,500 for legal fees incurred in the review of the Klompas Separation Agreement, and reimbursement for laptop and provision of related peripherals;

•Entry into a consulting services agreement (the “Klompas Consulting Agreement”), whereby Mr. Klompas will assist with certain transitional matters at the request and direction of Zymeworks BC on an as needed basis. The Klompas Consulting Agreement became effective on June 30, 2023 and is scheduled to expire on June 30, 2025. Mr. Klompas will be entitled to continued vesting and exercise benefits for outstanding stock options and restricted stock units under our equity incentive plans for the duration of the Klompas Consulting Agreement as well as certain cash payments at a rate of $300/hour for any services provided in excess of five hours per week. If a change of control (as such term is defined in the Equity Compensation Plan) had occurred prior to the expiration or earlier termination of the Klompas Consulting Agreement, any unvested options and restricted stock units held by Mr. Klompas immediately prior to such change of control that would have vested on or prior to June 30, 2025 had Mr. Klompas remained as a service provider through such date, would have been accelerated such that they would have been vested as of immediately prior to and contingent upon such change of control. Following the termination of the Klompas Consulting Agreement, and provided that Mr. Klompas (i) had not been terminated for cause prior to June 30, 2023 (Mr. Klompas was not terminated for cause prior to such date) and (ii) timely executed a supplemental release agreement, Mr. Klompas will have the period from the termination of the Klompas Consulting Agreement to June 30, 2026 to exercise any vested Company stock options, subject to any such options’ earlier expiration during such period; and

•Reimbursement for all reasonable and documented business expenses actually and properly incurred in relation to Zymeworks BC’s and our business up to June 30, 2023.

In addition to providing a release of claims in favor of the Company, the Klompas Separation Agreement reaffirmed Mr. Klompas’ agreement to be bound by the confidentiality provisions and the restrictive covenants of his employment agreement, which include a requirement that Mr. Klompas not solicit our employees to terminate their relationship with us while he is employed by us and for up to one year following the termination of his employment with us, and a requirement, modified by the Klompas Separation Agreement, that he will not compete with us, while employed by us and for up to six months following the termination of his employment, either directly or indirectly, with respect to certain aspects of our business with which he was materially involved in the last 12 months of his employment with us.

Prior to Mr. Klompas’ separation from employment with us, Mr. Klompas was subject to an employment agreement with us, which had been entered into with him on January 25, 2007 and amended from time to time, as well as to the later Klompas Promotion Letter, described below.

The 2007 employment agreement with Mr. Klompas had set forth the initial terms and conditions of his employment and had provided for his initial base salary and initial equity award, and which included, among other things, provisions regarding confidentiality, ownership of developments, non-competition and non-solicitation, as well as eligibility for our incentive plans, reimbursements for certain professional association memberships and professional development fees and costs, and the ability to participate in generally available benefits. This agreement was amended on October 23, 2007, and January 1, 2014. On January 17, 2017, we entered into an amended and restated employment agreement with Mr. Klompas that superseded and replaced the January 2007 agreement, as amended, and set forth revised termination and change of control provisions. Under the revised not-for-cause termination severance provisions, during the first three years of employment, Mr. Klompas was entitled to 12 months of written notice or payment in lieu of notice equal to 12 months of his base salary and continuation of benefits for 12 months, or any combination thereof. Commencing in the fourth year of employment, Mr. Klompas was entitled to an additional one month’s notice, or the equivalent base salary and continuation of benefits, or any combination thereof, for each additional completed year of service, up to a total maximum of 18 months. If Mr. Klompas were terminated without cause within 12 months following a change of control, he would have received severance equal to 18 months of his base salary, continuation of benefits for 18 months and full vesting acceleration of all unvested stock options or other equity grants made as at that date. Any severance payments payable under the agreement in excess of any minimum required by certain applicable laws were conditional upon Mr. Klompas’ release of claims against us.

In connection with Mr. Klompas’ appointment as Chief Operating Officer in January 2022, we provided Mr. Klompas with a promotion letter (the “Klompas Promotion Letter”), which reflected increases to his then-current base salary and annual bonus opportunity. In January 2023, Mr. Klompas’ base salary was increased to $500,000, which increase was given retroactive effect to August 4, 2022 in connection with his appointment as President, and his annual target bonus remained at 45% of his base salary.

Christopher Astle. In connection with Dr. Christopher Astle’s appointment as Senior Vice President and Chief Financial Officer, we entered into an amended and restated employment agreement with Dr. Astle effective as of February 24, 2022 (the “Astle Employment Agreement”). The Astle Employment Agreement does not have a specific term.

Pursuant to the Astle Employment Agreement, Dr. Astle is entitled to the following compensation and benefits:

•An annual base salary of $375,000, with eligibility to earn an annual discretionary bonus of up to 35% of his annual base salary, based upon the achievement of certain Company goals determined by the board of directors. Dr. Astle’s current annual base salary is $425,000 and his target annual discretionary bonus for 2024 has been set at 40% of his annual base salary;

•Options, which were granted to Dr. Astle in 2022, to purchase 125,000 of our common shares at an exercise price per share equal to the fair market value on the date of grant. The options were granted under the Equity Compensation Plan. 25% of the options will vest and become exercisable on the one-year anniversary of the date of grant, and thereafter 1/36 th of the remaining options will vest on the last day of each month, until all of the options have vested, subject to Dr. Astle’s continued service;

•Eligibility to participate in our employee benefit plans, policies and arrangements, as well as reimbursement for certain fees and costs related to membership in certain professional associations and professional development;

•If we terminate Dr. Astle’s employment without cause prior to April 1, 2024, then Dr. Astle will be eligible to receive twelve months of notice or the equivalent of twelve months of base salary as of the date notice is given, or any combination thereof that totals twelve months of combined notice and base salary. Commencing in the fourth year of his employment, if we terminate Dr. Astle’s employment without cause, Dr. Astle will be eligible to receive an additional one month of notice or the equivalent of one month of base salary as of the date notice is given, or any combination thereof, for each additional completed year of service after April 1, 2024, up to a total maximum of eighteen months. Dr. Astle will also be eligible for continuation of group health and dental benefits through the applicable notice period to the extent permitted by any applicable benefit plan. Such payments will be subject to Dr. Astle entering into a valid settlement agreement with us;

•If Dr. Astle’s employment is terminated by us without cause on or within twelve months following a change of control (as defined in the Astle Employment Agreement), Dr. Astle will be eligible to receive (x) eighteen months of base salary, (y) group extended health and dental benefits continuation as of the date of termination for eighteen months and (z) full vesting acceleration of all unvested and outstanding stock options or other equity grants as of the date of termination. Such payments will be subject to Dr. Astle entering into a valid settlement agreement with us; and

•In addition, the Astle Employment Agreement requires Dr. Astle, among other things, not to compete, either directly or indirectly, with us while employed by us and for up to six months following the termination of his employment with us. The Astle Employment Agreement also requires Dr. Astle not to solicit our employees to terminate their relationship with us while he is employed by us and for up to one year following the termination of his employment with us.

On November 17, 2022, we entered into an amendment with Dr. Astle to the Astle Employment Agreement. The amendment amends the Astle Employment Agreement to provide to Dr. Astle certain corporate housing benefits based on need (as determined in our discretion) in the Vancouver, British Columbia metropolitan area. In addition to the corporate housing benefits, the amendment provides for a gross-up to Dr. Astle for the impact of any tax withholding related to the corporate housing benefits.

Paul Moore. On July 18, 2022, the Company and Zymeworks Biopharmaceuticals Inc., a subsidiary of the Company, entered into an employment agreement with Dr. Moore setting forth the terms and conditions of his employment as Chief Scientific Officer of the Company (the “Initial Employment Agreement”). In connection with Dr. Moore’s planned relocation from the United States to Canada, the Company and our subsidiary Zymeworks BC entered into an amended and restated employment agreement with Dr. Moore (the “Moore Employment Agreement”) that supersedes and replaces the Initial Employment Agreement. The Moore Employment Agreement does not have a stated term.

Pursuant to the Moore Employment Agreement, Dr. Moore is entitled to the following compensation and benefits:

•An annual base salary of $465,000, with eligibility to earn an annual discretionary bonus of up to 45% of his annual base salary, based upon the achievement of certain Company goals determined by the board of directors. Dr. Moore’s current annual base salary is $495,000 and his target annual discretionary bonus remains at 45% of his annual base salary;

•Eligibility to participate in our employee benefit plans, policies and arrangements, as well as reimbursement for certain fees and costs related to membership in certain professional associations and professional development;

•Reimbursement of relocation expenses up to a maximum of $200,000, grossed-up to offset the impact of any taxes on such payment, for reasonable and customary moving expenses that Dr. Moore incurs within eighteen months of his July 18, 2022 start date in connection with his relocation to the Vancouver, British Columbia metropolitan area, as contemplated in the Initial Employment Agreement.

•A tax equalization payment if Dr. Moore is subject to income taxation in Canada in a given year equal to the difference between (i) the sum of total Canadian taxes plus any U.S. federal, state and local income taxes, that Dr. Moore is or would be obligated to pay for an applicable tax year, and (ii) the amount of U.S. federal, state and local tax liability had Dr. Moore worked in the United States for the entire tax year. Any tax equalization payment will be grossed-up to offset the impact of taxes on such payment.

•Provision of tax preparation support or reimbursement of up to $5,000 per year for additional tax preparation expenses of Dr. Moore for a period of two years from his July 18, 2022 start date.

•If we terminate Dr. Moore’s employment without cause during his first three years of employment, then Dr. Moore will be eligible to receive twelve months of notice or the equivalent of twelve months of base salary as of the date notice is given, or any combination thereof that totals twelve months of combined notice and base salary. Commencing in the fourth year of his employment, if we terminate Dr. Moore’s employment without cause, Dr. Moore will be eligible to receive an additional one month of notice or the equivalent of one month of base salary as of the date notice is given, or any combination thereof, for each additional completed year of service, up to a total maximum of eighteen months. Dr. Moore will also be eligible for continuation of group health and dental benefits through the applicable notice period to the extent permitted by any applicable benefit plan; Such payments will be subject to Dr. Moore entering into a valid separation and release agreement with us;

•If Dr. Moore’s employment is terminated by us without cause on or within twelve months following a change of control (as defined in the Moore Employment Agreement), Dr. Moore will be eligible to receive as severance (x) eighteen months continued base salary following termination, (y) group extended health and dental benefits as of the date of termination for eighteen months, and (z) full vesting acceleration of all unvested and outstanding stock options or other equity grants as of the date of termination. Such payments will be subject to Dr. Moore entering into a valid separation and release agreement with us; and

•In addition, the Moore Employment Agreement requires Dr. Moore, among other things, not to compete, either directly or indirectly, with us while employed by us and for up to six months following the termination of his employment with us. The Moore Employment Agreement also requires Dr. Moore not to solicit our employees to terminate their relationship with us while he is employed by us and for up to one year following the termination of his employment with us.

Equity Compensation Plan Information

Under our Original Plan, upon a transaction in which equity securities representing more than 66 2/3% of our common stock are sold (a “substantial sale”), if the purchaser offers to buy out options, the options must be sold to the purchaser at a purchase price equal to (x) the price per share in the transaction (calculated in accordance with the terms of the Original Plan) minus the exercise price per share, multiplied by (y) the number of shares then exercisable under the option. If the option holders do not sell their options to the purchaser, such options will terminate upon completion of the substantial sale.

Under our Equity Compensation Plan and our Inducement Plan, in connection with a change of control (as defined in the applicable plan), our board of directors or the committee to which our board of directors has delegated authority to administer the applicable plan (either, the “Administrator”) has the right to provide for the conversion or exchange of any outstanding awards into or for options, rights or other securities in any entity participating in or resulting from a change of control, cash or other property. If we enter into an agreement for a transaction that, if completed, would result in a change of control, or otherwise becomes aware of a pending change of control, we will give written notice to the award holders regarding the potential change of control and a description of the effect of the change of control on outstanding awards at least seven (7) days prior to the closing of change of control.

Under our Equity Compensation Plan and Inducement Plan, the Administrator may, in its discretion, accelerate the vesting and/or expiration date of any or all outstanding awards in connection with the change of control to provide that such designated awards shall be fully vested and any options not exercised within the specified period will be terminated after the completion of the change of control. If the change of control would also result in a capital reorganization, arrangement, amalgamation or reclassification of our share capital (and if the vesting and expiration of the awards has not been accelerated as contemplated by the prior sentence), upon completion of the change of control, the number and kind of shares subject to outstanding awards and, if applicable, the exercise price per share of options shall be appropriately adjusted (including by substituting the awards for awards with respect to securities in any successor entity to us) in such manner as the Administrator considers equitable to prevent substantial dilution or enlargement of the rights granted to Award holders. The Administrator also may make changes to the terms of the awards or the Equity Compensation Plan or Inducement Plan to the extent necessary or desirable to comply with any rules, regulations or policies of any stock exchange on which any of our securities may be listed, provided that the value of previously granted awards and the rights of award holders are not materially adversely affected by any such changes. In addition, in the event of a potential change of control, the Administrator may, in its sole discretion, modify the terms of the plan and/or the awards to assist the participants to tender into a take-over bid or other transaction leading to a change of control, including the authority to allow participants to conditionally exercise options.

Director Compensation Table

The following table presents the compensation awarded to, earned by or paid to our directors (other than Mr. Galbraith, whose compensation is provided in the Summary Compensation Table above) for the year ended December 31, 2023. Dr. Cesano and Mr. Platshon are not included in the table below as they did not join the board of directors until 2024. We do not currently have director compensation in the form of share-based awards (other than stock options), non-equity incentive plan compensation or non-qualified deferred compensation.

(1) The amounts set forth in this column reflect the aggregate grant date fair value for option awards computed in accordance with Financial Accounting Standards Board Accounting Standards Codification Topic 718, Compensation – Stock Compensation. See Note 2 to the “Notes to Consolidated Financial Statements – Summary of Significant Accounting Policies – Stock-Based Compensation” and Note 10(e) “Notes to Consolidated Financial Statements – Stockholders’ Equity Stock- Based Compensation” included in this Annual Report on Form 10-K for our year ended December 31, 2023.

(2) As of December 31, 2023, directors held the following number of options to purchase Company common shares: (i) Mr. Campoy, 87,000; (ii) Mr. Cox, 110,000; (iii) Dr. Davidson, 74,000; (iv) Dr. Hillan, 121,425; (v) Dr. Mahony, 110,000; (vi) Mr. Miller, 87,000; (vii) Dr. Neu, 71,000; (viii) Mr. Renton, 121,425; (ix) Dr. Sacks, 78,140; and (x) Ms. Zoth, 86,117.

(3) In 2023, cash compensation for non-employee directors was paid in advance for directors serving on the board of directors at the beginning of each of the first, second, third and fourth quarters of 2023. In the fourth quarter of 2023, the board of directors changed the cash compensation approach such that, going forward, cash compensation would be payable quarterly in arrears. As a result of this change, the amount included in this column for Dr. Davidson reflects the pro-rated cash compensation earned during the fiscal year ended December 31, 2023 by Dr. Davidson.

(4) Mr. Miller provided consulting services to us pursuant to the Consulting Agreement (as defined below) the Company entered into with Derek J Miller Consulting LLC, a limited liability company owned by Derek Miller in May 2022. The amounts set forth above reflect consulting fees paid to Mr. Miller for the year ended December 31, 2023. In total, we have paid Mr. Miller an aggregate of approximately $36,000 for such consulting services, of which (i) approximately $22,000 was paid for services rendered prior to Mr. Miller’s appointment to the board of directors and (ii) approximately $14,000 was paid for services rendered since Mr. Miller joined the board of directors. In October

2023, we entered into a Termination of Consulting Agreement and Further Amended and Restated Statement of Work #1 with Derek J Miller Consulting LLC, which provided for, among other things, the termination of the Consulting Agreement effective as of November 30, 2023.

(5) Dr. Neu joined the Company’s board of directors in March 2020. Dr. Neu was an employee of Baker Bros. Advisors LP until January 2021. Pursuant to the terms of Dr. Neu’s employment by Baker Brothers Advisors LP, the options granted to him in 2020 were, and will continue to be, beneficially owned by Baker Bros. Advisors LP.

Director Compensation

The written charter of our compensation committee provides that the compensation committee will review compensation for members of our board of directors on at least an annual basis, taking into account their responsibilities and time commitment and information regarding the compensation paid at peer companies. The compensation committee will make recommendations to our board of directors with respect to changes to our approach to director compensation as it considers appropriate.

In November 2022, the compensation committee worked with Aon to update prior competitive assessments of our board of director compensation program. Based on these findings, in November 2022, the compensation committee recommended, and the board of directors approved, the following changes to the cash and equity compensation of non-employee directors:

•The cash component for board of directors and committee membership was maintained at the 2022 levels, with the exception that the cash retainer fee for service as chair of the compensation committee was increased from $10,000 to $12,000, the cash retainer fee for service as a member of the compensation committee was increased from $5,000 to $6,000, the cash retainer fee for service as chair of the nominating and corporate governance committee increased from $7,500 to $8,500, and the cash retainer fee for service as a member of the nominating and corporate governance committee was increased from $3,750 to $4,250 (in each case effective January 2023);

•The initial option grant for new directors, to be granted on or about the time of the director joining the board of directors, was changed from 40,000 to 50,000 options, with the vesting schedule remaining as 1/36 th of the options vesting on each monthly anniversary of the grant date, subject to the director’s continued service (effective November 2022); and

•The annual equity grant to directors, to be granted at or about the time of our annual meeting of stockholders, was changed from 20,000 options to 25,000 options, with the vesting schedule remaining 100% of the options vesting on the date of the next year’s annual meeting of stockholders, subject to the director’s continued service through such date (effective November 2022).

In May 2023, the board of directors approved, with input from the compensation committee and nominating and corporate governance committee, certain amendments to our board of directors compensation program to provide for: (i) full acceleration of vesting of options granted as annual equity awards in connection with our 2022 annual meeting of stockholders for directors departing on or after the restatement of the policy on May 24, 2023 and at or prior to the 2023 annual meeting of stockholders, (ii) pro rata acceleration of vesting of options granted as annual equity awards in connection with the 2023 annual meeting of stockholders for directors departing after the 2023 annual meeting of stockholders but at or before our 2024 annual meeting of stockholders, with the pro rata acceleration determined based on the number of full or partial months served as a non-employee director on and after the 2023 annual meeting of stockholders date, and (iii) extension of the post-termination exercise period for vested options held by departing directors to three years following the director’s cessation of service (or, if earlier, upon the expiration of the option).

In November 2023, the compensation committees worked with Aon to again update prior competitive assessments of our board of director compensation program. Based on these findings, in November 2023, the compensation committee recommended certain changes to the non-employee director compensation program.

In December 2023, the board of directors approved, following its annual assessment of the director compensation program and including its consideration of the input and recommendations from the compensation committee, the following changes to the cash and equity compensation of non-employee directors (as amended, the “Amended and Restated Director Compensation Policy”), which changes adjust the director compensation program to more closely align with the non-employee director compensation practices of the Company’s peer group:

•Beginning January 1, 2024, the annual cash retainer fee for service as chair of the audit committee will be increased from $15,000 to $20,000, the annual cash retainer fee for service as a member of the audit committee will be increased from $7,500 to $10,000, the annual cash retainer fee for service as chair of the compensation committee will be increased from $12,000 to $15,000, the annual cash retainer fee for service as a member of the compensation committee will be increased from $6,000 to $7,500, the annual cash retainer fee for service as chair of the nominating and corporate governance committee will be increased from $8,500 to $10,000, the annual cash retainer fee for service as a member of the nominating and corporate governance committee will be increased from $4,250 to $5,000;

•Effective immediately, the initial option grants for new non-employee directors, to be granted on or about the time of the director joining the board of directors, were changed from options to purchase 50,000 shares of Company common stock to options to purchase 74,000 shares of Company common stock, with the vesting schedule remaining as 1/36th of the shares subject to the option vesting on each monthly anniversary of the grant date, subject to the director’s continued service; and

•Effective immediately, the annual equity grant to continuing non-employee directors, to be granted at or about the time of our annual meeting of stockholders, was changed from options to purchase 25,000 shares of Company common stock to 37,000 shares, with the vesting schedule remaining 100% of the shares subject to the option vesting on the date of the next year’s annual meeting of stockholders, subject to the optionee’s continued service through such date.

Following the recommendation of the compensation committee, the board of directors also determined to not implement stock ownership guidelines at this time. No other changes to board of director compensation were made for 2023.

Cash Compensation for Directors

In 2023, we provided the below annual cash retainer fees for service on our board of directors and committees. The fees for service on committees are in addition to the annual retainer fees for service on the board of directors.

Cash retainer fees were amended in December 2023 as discussed above.

Equity Compensation for Directors

Beginning from December 2023, new non-employee directors will be granted an initial option grant to purchase 74,000 shares of common stock, to be granted on or about the time such director joins the board of directors, with a vesting schedule of 1/36th of the options vesting on each monthly anniversary of the grant date, subject to the optionee’s continued service through such date.

In addition, non-employee directors will be granted an annual option grant to purchase 37,000 shares of common stock, to be granted at or about the time of the Company’s annual meeting of stockholders, with a vesting schedule of 100% of the options vesting on the date of the next year’s annual meeting of stockholders, subject to the optionee’s continued service through such date.

Upon cessation of a non-employee director’s continued service, each outstanding stock option held by such director is subject to (i) full acceleration of vesting of options granted as annual equity awards in connection with our 2022 annual meeting of stockholders for directors departing on or after May 24, 2023 and at or prior to the 2023 annual meeting of stockholders held on December 7, 2023 and (ii) pro rata acceleration of vesting of options granted as annual equity awards in connection with the 2023 annual meeting of stockholders for directors departing after the 2023 annual meeting of stockholders, but at or before our 2024 annual meeting of stockholders, with the pro rata acceleration determined based on the number of full or partial months served as a non-employee director on and after the 2023 annual meeting of stockholders date.

In addition, the post-termination exercise period for vested options held by departing directors is extended to three years following the director’s cessation of service (or, if earlier, upon the expiration of the option).

Expense Reimbursement

Each member of our board of directors is also entitled to reimbursement for reasonable travel and other expenses incurred in connection with attending board meetings and meetings for any committee on which he or she serves. These amounts are not included in the table above.

Risk Management

As part of its normal practice, the compensation committee evaluates the risk-taking incentives created by our compensation programs, policies and practices and has concluded that such programs, policies and practices are not reasonably likely to have a material adverse effect on the Company.