A record holder holds shares in his or her name. Shares held in “street name” means shares that are held in the name of a bank or broker on a person’s behalf. If your shares are held by a bank or a brokerage firm, you are considered the “beneficial owner” of those shares held in “street name.”

If, on March 12, 2021,24, 2024, your ordinary shares were held in an account at a brokerage firm, bank or other similar organization and you are the beneficial owner of shares, these proxy materials should be forwarded to you by that organization. The organization holding your account is considered the shareholder of record

We will solicit proxies and will bear the entire cost of this solicitation. The initial solicitation of proxies may be supplemented by additional mail communications and by telephone, fax, e-mail, internet and personal solicitation by our directors, officers or other employees. No additional compensation for soliciting proxies will be paid to our directors, officers or other employees for their proxy solicitation efforts. We also will reimburse Citibank, N.A. for their expenses in sending materials, including ADS voting instructions, to ADS holders of record.

If you hold your ordinary shares in more than one account, you will receive a form of proxy for each account. To ensure that all of your shares are voted, please sign, date and return all forms of proxy. Please be sure to vote all of your shares.

At the AGM, our Board of Directors will present our U.K. statutory Directors’ Remuneration Report for the year ended December 31, 2020,2023, as set out on pages 28[  ] to 46[  ] of the 20202023 U.K. Annual Report appended as Annex A to this proxy statement. The U.K. statutory Directors’ Remuneration Report includes the annual report on remuneration. This document describes in detail our remuneration policies and procedures and explains how these policies and procedures help to achieve our compensation objectives with regard to our directors and the retention of high-quality directors. Our Board of Directors and the Remuneration Committee of the Board of Directors (the “Remuneration Committee”) believe that the policies and procedures as articulated in the directors’ remuneration report are effective and that as a result of these policies and procedures we have and will continue to have high-quality directors. Our Board of Directors has approved and signed the report in accordance with English law.

At the AGM, the shareholders will vote on the Director’sDirectors’ Remuneration Report. This vote is advisory and non-binding. Although non-binding, our Board of Directors and Remuneration Committee will review

Based on its discussions with management and the independent registered public accounting firm, and its review of the representations and information provided by management and the independent registered public accounting firm, the Audit Committee recommended to the Board of Directors that the audited consolidated financial statements be included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2020.2023.

As a U.K.-incorporated company, the Company’s ordinary shareholders are entitled, under Section 561(1) of the Companies Act, to pre-emption rights, whereby, in the event that the Company wishes to allot new equity securities for cash, those securities must first be offered to existing shareholders in proportion to the number of ordinary shares they each hold before they can be offered to new shareholders.

Subject to and conditioned upon the passing of Proposal 1013 above, this Proposal 1114 authorizes the Board of Directors pursuant to Section 570 and 573 of the Companies Act to allot equity securities (as defined in Section 560 of the Companies Act) for cash pursuant to the authority conferred by Proposal 1013 above and/or to sell ordinary shares held by the Company as treasury shares for cash, as if Section 561(1) of the Companies Act did not apply to any such allotment or sale, provided that this power will be limited to

In accordance with our Articles of Association, one-third (or such number nearest to but not exceeding one-third) of the Company’s directors retire from office at every annual general meeting of shareholders. Retiring directors are eligible for re-election and, if no other director is elected to fill his or her position and the director is willing, shall be re-elected by default. The directors to retire at the annual generalAGM in every year shall include (so far as necessary to obtain the number required) any director who wishes to retire and not to offer himself or herself for re-election. Any further directors so to retire shall be the directors who have been longest in office since their last election. As between directors of equal seniority, the directors to retire shall in the absence of agreement be selected from among them by lot. Of the nine directors subject to retirement by rotation, David Ebsworth, Ph.D.,Lisa Deschamps, Martin Edwards, M.D. and Anders Ullman, M.D., Ph.D. will, on this occasion, retire from office and stand for re-election by our shareholders.

Having carried out an evaluation of the individual performance of each of Lisa Deschamps, David Ebsworth, Ph.D., Martin Edwards, M.D. and, Anders Ullman, M.D., Ph.D., Christina Ackermann and Michael Austwick with the support of the Nomination and Corporate Governance Committee, our Board of Directors is satisfied that their performance continues to be effective and that they continue to demonstrate commitment to their roles. The Board of Directors considers that it is entirely appropriate for each of Ms.Lisa Deschamps, Dr. Ebsworth, Dr.Martin Edwards, M.D., Anders Ullman, M.D., Ph.D., Christina Ackermann and Dr. UllmanMichael Austwick to seek re-election at the AGM.

Each of the above directors has been nominated for re-election and no other nominees for directors have been presented. Therefore, it is anticipated that following the AGM, if all of the above directors are re-elected, the Board of Directors will be comprised of teneleven members, including one executive director and nineten non-executive directors.

All of our directors, other than David Zaccardelli, Pharm.D., qualify as “independent” in accordance with Nasdaq listing requirements. The Nasdaq independence definition includes a series of objective tests, including that the director is not, and has not been for at least three years, one of our employees and that neither the director nor any of his or her family members has engaged in various types of business dealings with us. In addition, as required by Nasdaq rules, our Board of Directors has made a subjective determination as to each independent director that no relationships exist, which, in the opinion of our Board of Directors, would interfere with the exercise of independent judgment in carrying out the responsibilities of a director. In making these determinations, our Board of Directors reviewed and discussed information provided by the directors and us with regard to each director’s business and personal activities and relationships as they may relate to us and our management, including that Mr. Gupta and Dr. Shah are affiliated with certain of our significant stockholders.shareholders. The Board of Directors previously determined that Mr. Rishi Gupta qualified as an independent director prior to his resignation on January 31, 2024. Dr. Zaccardelli is not independent because he is the President and Chief Executive Officer of our Company. Jan-Anders Karlsson, Ph.D, our former President and Chief Executive Officer, did not qualify as independent during the period he served on our Board in 2020 until his departure on February 2, 2020.

The Nomination and Corporate Governance Committee is primarily responsible for searching for qualified director candidates for election to the Board and filling vacancies on the Board of Directors. To

In evaluating the suitability of individual candidates (both new candidates and current Board members), the Nomination and Corporate Governance Committee, in recommending candidates for election, and the Board of Directors, in approving (and, in the case of vacancies, appointing) such candidates, may take into account many factors, including but not limited to: personal and professional integrity, ethics and values; experience in corporate management, such as serving as an officer or former officer of a publicly held company; strong finance experience; relevant social policy concerns; experience relevant to the Company’s industry; experience as a board member or executive officer of another publicly held company; relevant academic expertise or other proficiency in an area of the Company’s operations; diversity of expertise and experience in substantive matters pertaining to the Company’s business relative to other board members; diversity of background and perspective, including, but not limited to, with respect to age, gender, race, place of residence and specialized experience; practical and mature business judgment, including, but not limited to, the ability to make independent analytical inquiries; and any other relevant qualifications, attributes or skills. The Board of Directors evaluates each individual in the context of the Board of Directors as a whole, with the objective of assembling a group that can best perpetuate the success of the business and represent shareholder interests through the exercise of sound judgment using its diversity of experience in these various areas. In determining whether to recommend a director for re-election, the Nomination and Corporate Governance Committee may also consider the director’s past attendance at meetings and participation in and contributions to the activities of the Board of Directors.

The Nomination and Corporate Governance Committee and the Board have not established a formal policy with regard to the consideration of director candidates recommended by shareholders. This is due to the following factors: (i) the limited number of such recommendations, (ii) the need to evaluate such recommendations on a case-by-case basis, and (iii) the expectation that recommendations from shareholders would be considered in the same manner as recommendations by directors, officers, outside advisors or search firms in the event of a vacancy on the Board.

Shareholders who desire to nominate persons directly for election to the Board of Directors at an annual general meeting of shareholders must meet the deadlines and other requirements set forth under “Additional Information — Shareholder Proposals for 20222025 Annual General Meeting.” Any vacancies on the Board of Directors occurring between our annual general meetings of shareholders may be filled by a majority of the directors then in office, in which case any director so elected will serve until the next annual general meeting of shareholders when such director will offer himself or herself for re-election, or by ordinary resolution of the shareholders of the Company.

The Board of Directors will give appropriate attention to written communications that are submitted by shareholders, and will respond if and as appropriate. Our Company Secretary and General Counsel are primarily responsible for monitoring communications from shareholders and for providing copies or summaries to the directors as they consider appropriate.

Based on the Company’s present circumstances, the Board believes that the Company and its shareholders are best served by having Dr. Ebsworth serve as its ChairmanChairperson of the Board and Dr. Zaccardelli serve as its Chief Executive Officer. Our current leadership structure permits Dr. Zaccardelli to focus his attention on managing our Company and permits Dr. Ebsworth to manage the Board of Directors. Accordingly, we believe our current leadership structure is the optimal structure for us at this time. However, our Board of Directors will continue to periodically review our leadership structure and may make such changes in the future as it deems appropriate.

Risk assessment and oversight are an integral part of our governance and management processes. Our Board of Directors encourages management to promote a culture that incorporates risk management into our corporate strategy and day-to-day business operations. Management discusses strategic and operational risks at regular management meetings and conducts specific strategic planning and review sessions during the year that include a focused discussion and analysis of the risks facing us. Throughout the year, senior management reviews these risks with the Audit Committee or Board of Directors at regular meetings as part of management presentations that focus on particular business functions, operations or strategies, and presents the steps taken by management to mitigate or eliminate such risks. As provided in the terms of reference of the Audit Committee, the Audit Committee is responsible for discussing the Company’s policies with respect to risk assessment and risk management, including guidelines and policies to govern the process by which the Company’s exposure to risk is handled. In accordance with those policies, the Board and the Board committees have an active role in overseeing management of the Company’s risks inherent in their respective areas of oversight. In particular, our Board of Directors is responsible for monitoring and assessing strategic risk exposure, including business continuity risks, such as risks relating to the COVID-19 pandemic.risks. The Audit Committee monitors compliance with legal and regulatory requirements, discusses the Company’s policies with respect to risk assessment and risk management, including guidelines and policies to govern the process by which the Company’s exposure to risk is handled, oversees management of the Company’s financial and cybersecurity risks, and considers and approves or disapproves any related person transactions. Our Nomination and Corporate Governance Committee monitors the risks relating to our corporate governance framework and succession planning for our Board of Directors and senior management. Our Remuneration Committee assesses and monitors whether any of our remuneration policies and programs has the potential to encourage excessive risk-taking. While each committee is responsible for evaluating certain risks and overseeing the management of such risks, the entire Board has an active role in overseeing management of the Company’s risks and is regularly informed through committee reports about such risks. The Board does not believe that its role in the oversight of our risks adversely affects the Board’s leadership.

Our Corporate Governance Guidelines require the Nomination and Corporate Governance Committee to oversee a periodic assessment of the Board and its committees.

The current members of the Audit Committee are Christina Ackermann, James Brady, David Ebsworth, Ph.D., Andrew Sinclair, Ph.D., and Vikas Sinha. Mr. Sinha serves as the Chairperson of the Audit Committee. The members of our Audit Committee meet the requirements for financial literacy under the applicable rules of the SEC and Nasdaq. Our Board of Directors has determined that each of Vikas Sinha and James Brady is an “audit committee financial expert” as defined by Item 407(d)(5)(ii) of Regulation S-K.

The Audit Committee meets as often as one or more members of the Audit Committee deem necessary, but in any event, meets at least four times per year. The Audit Committee meets at least once per year with our independent accountant, without our management being present. The Audit Committee met five6 times in 2020.2023.

The Remuneration Committee has the authority to retain or obtain the advice of remuneration consultants, legal counsel and other advisors to assist in carrying out its responsibilities, including being directly responsible for the appointment, oversight and compensation of such consultant, counsel or advisor and the ability to cause us, without further action by the Board of Directors, to pay the compensation of such consultant, counsel or advisor as approved by the Remuneration Committee, provided, however, that in retaining or obtaining the advice of such consultant, counsel or advisor, other than in-house legal counsel, the Remuneration Committee shall take into consideration the factors affecting independence required by applicable SEC rules and Nasdaq rules. The Remuneration Committee also has the authority to conduct or authorize investigations into any matters within the scope of its responsibilities as it shall deem appropriate, including the authority to request any officer, employee or advisor of us to meet with the Remuneration Committee or any advisors engaged by the Remuneration Committee.

The current members of our Remuneration Committee are Ken Cunningham, M.D., David Ebsworth, Ph.D. and Rishi Gupta.Mahendra Shah, Ph.D. Dr. Cunningham serves as the Chairperson of the Remuneration Committee.

The named executive officers receive a base salary to compensate them for services rendered to our company.Company. The base salary payable to each named executive officer is intended to provide a fixed component of compensation reflecting the executive’s skill set, experience, role and responsibilities.