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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934 (Amendment No. )

Filed by the Registrant ☒ Filed by a party other than the Registrant ☐

Check the appropriate box:

FUSION PHARMACEUTICALS INC.

(Name of Registrant as Specified in its Charter)

Not applicable.

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check all boxes that apply):

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FUSION PHARMACEUTICALS INC.

270 LONGWOOD ROAD SOUTH

HAMILTON, ONTARIO, CANADA L8P 0A6

(289) 799-0891

NOTICE OF 2023 ANNUAL MEETING OF

SHAREHOLDERS

To Be Held on June 14, 2023

To Our Shareholders:

You are cordially invited to attend the 2023 Annual Meeting of Shareholders of Fusion Pharmaceuticals Inc. (the “Annual Meeting”). The Annual Meeting will be held online on Wednesday, June 14, 2023 at 10:00 a.m., Eastern Time. You may attend the meeting virtually by registering at https://www.proxydocs.com/FUSN, where you will be able to vote electronically and submit questions, subject to the registration procedures set forth below.

Only shareholders who owned common shares at the close of business on April 18, 2023 can vote at the Annual Meeting or any adjournment that may take place. At the Annual Meeting, the shareholders will consider and vote on the following matters:

As noted above, our Annual Meeting will be a “virtual meeting” of shareholders, which will be conducted exclusively via the Internet. There will not be a physical meeting location, and shareholders will not be able to attend the Annual Meeting in person. You may attend the Annual Meeting via the Internet, vote your shares during the Annual Meeting and submit questions before the Annual Meeting by registering at https://www.proxydocs.com/FUSN.

In order to attend the meeting online, vote your shares electronically during the meeting and submit questions before the meeting, registered shareholders must register in advance at https://www.proxydocs.com/FUSN using the control number located in the box in the upper right-hand corner of your proxy card or in the body of the e-mail notification you received. Most of our shareholders do not hold shares directly in their own name but instead are non-registered shareholders who beneficially own shares that are held by an intermediary, such as their bank, trust company, securities broker, trustee or other nominee. If you are a non-registered shareholder and wish to attend the meeting online, vote your shares electronically during the meeting and submit questions before the meeting, you must appoint yourself as your proxyholder following the procedures provided to you by your intermediary and register in advance at https://www.proxydocs.com/FUSN. Upon completing your registration, you will receive further instructions via email, including your unique links that will allow you to access the meeting and will permit you to submit questions. Further information about how to attend the Annual Meeting online, vote your shares and submit questions is included in the accompanying proxy statement.

You can find more information, including the nominees for director, in the proxy statement for the Annual Meeting, which is attached and also available for viewing, printing and downloading at https:// www.proxydocs.com/FUSN. As outlined in the attached proxy statement, the board of directors recommends that you vote in favor of each director nominee in Proposal 1 and in favor of Proposal 2.

Instead of mailing a paper copy of our proxy materials to all of our shareholders, we are providing access to our proxy materials via the Internet under Canadian and U.S. securities laws. As a result, we are sending to our shareholders a Notice of Internet Availability of Proxy Materials (the “Notice”), instead of a paper copy of this proxy statement and our Annual Report on Form 10-K for the fiscal year ended December 31, 2022 (the “2022 Annual Report”). This Notice is dated April 27, 2023 and we plan to mail the Notice on or about April 28, 2023. The Notice contains instructions on how to access our proxy materials over the Internet. The Notice also contains instructions on how each of our shareholders can receive a paper copy of our proxy materials, including the proxy statement, our 2022 Annual Report, and a form of proxy card.

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Shareholders of record at the close of business on April 18, 2023, the record date for the Annual Meeting, are entitled to notice of, and to vote at, the Annual Meeting or any adjournment or postponement of the Annual Meeting. A complete list of registered shareholders will be available to shareholders of record during the Annual Meeting.

Your vote is very important, regardless of the number of shares you own. Whether or not you expect to attend the Annual Meeting, please vote your shares by proxy in advance of the Annual Meeting to ensure your representation and the presence of a quorum at the Annual Meeting. To ensure that your vote is recorded promptly, please vote as soon as possible, even if you plan to attend the Annual Meeting.

If you are a shareholder of record, you may vote your shares by proxy in advance of the Annual Meeting on the Internet by visiting https://www.proxydocs.com/FUSN, by telephone by calling 866-834-5856 and following the recorded instructions or by completing, signing, dating, and returning a proxy card. If you mail your proxy card or vote by telephone or the Internet and then decide to vote your shares online during the Annual Meeting, you may still do so provided you register in advance at https://www.proxydocs.com/FUSN. Your proxy is revocable in accordance with the procedures set forth in the proxy statement.

If you are a non-registered shareholder, you will receive instructions from the holder of record that you must follow in order to vote your shares by proxy in advance of the Annual Meeting.

Thank you for your ongoing support and continued interest in Fusion Pharmaceuticals Inc.

The content and sending of the proxy statement has been authorized by order of the Board of Directors,

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270 LONGWOOD ROAD SOUTH

HAMILTON, ONTARIO, CANADA L8P 0A6

(289) 799-0891

PROXY STATEMENT

2023 ANNUAL MEETING OF SHAREHOLDERS

To Be Held on June 14, 2023

This proxy statement contains information about the 2023 Annual Meeting of Shareholders of Fusion Pharmaceuticals Inc. (the “Annual Meeting”), to be held on Wednesday, June 14, 2023 at 10:00 a.m., Eastern Time. The Annual Meeting will be held online via live webcast. In order to attend the Annual Meeting, you must register at https:www.proxydocs.com/FUSN. Upon completing your registration, you will receive further instructions via email, including a unique link that will allow you access to the Annual Meeting and to vote and submit questions during the Annual Meeting. There will not be a physical meeting location, and shareholders will not be able to attend the Annual Meeting in person. Further information about how to attend the Annual Meeting online is included in this proxy statement below. Except where the context otherwise requires, references to “Fusion Pharmaceuticals,” “Fusion,” “company,” “we,” “us,” “our” and similar terms refer to Fusion Pharmaceuticals Inc. and its consolidated subsidiaries.

This proxy statement summarizes information about the proposals to be considered at the meeting and other information you may find useful in determining how to vote. We are making this proxy statement, the related proxy card and our Annual Report on Form 10-K for the fiscal year ended December 31, 2022 (the “2022 Annual Report”), available to shareholders for the first time on or about April 28, 2023.

Pursuant to rules adopted by the Securities and Exchange Commission (the “SEC”), we are providing access to our proxy materials over the Internet instead of printing and mailing our proxy materials. As a result, we are mailing to our shareholders a Notice of Internet Availability of Proxy Materials (the “Notice”), instead of a paper copy of this proxy statement and the 2022 Annual Report. We plan to send the Notice on or about April 28, 2023. The Notice contains instructions on how each of our shareholders may access and review the proxy materials, including the Notice of Annual Meeting, proxy statement, proxy card and 2022 Annual Report, on the website referred to in the Notice. The Notice also contains instructions on how each of our shareholders may request that a paper copy of our proxy materials, including this proxy statement, our 2022 Annual Report, and a form of proxy card, be sent to such shareholder by mail.

Important Notice Regarding the Availability of Proxy Materials for

the Annual Meeting of Shareholders to be Held on June 14, 2023:

This proxy statement and our 2022 Annual Report are

available for viewing, printing and downloading at https://www.proxydocs.com/FUSN.

A copy of our 2022 Annual Report, as filed with the SEC and with Canadian securities regulators, except for exhibits, will be furnished without charge to any shareholder upon written request to Fusion Pharmaceuticals Inc., 270 Longwood Road South, Hamilton, Ontario. Canada L8P 0A6, Attention: Investor Relations. Exhibits will be provided upon written request and payment of an appropriate processing fee. This proxy statement and our Annual Report on Form 10-K for the fiscal year ended December 31, 2022 are also available on the SEC’s website at www.sec.gov and on the System of Electronic Document Analysis and Retrieval (“SEDAR”) at www.sedar.com.

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QUESTIONS AND ANSWERS ABOUT THE ANNUAL MEETING AND VOTING

Online registration will begin at 5:00 p.m., Eastern Time on April 28, 2023, and you should allow ample time for the online registration.

Upon completing your registration, you or your proxyholder will receive further instructions via email, including a unique link that will allow access to the meeting and enable you or your proxyholder to have the ability to submit questions. Please be sure to follow instructions found on your proxy card and/or voting authorization form and subsequent instructions that will be delivered to you via email.

You or your proxyholder may log on to the virtual meeting starting one hour before it begins. If you or your proxyholder encounter any difficulties accessing the virtual meeting during check-in or at the time of the virtual meeting, please contact technical support, whose contact information will be included in the email containing the

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unique link granting access into the meeting. There will be technicians standing by and ready to assist you with any technical difficulties you may have accessing the virtual meeting starting at 9:00 a.m., Eastern Time, on June 14, 2023.

Please note that you or your proxyholder can only access the virtual Annual Meeting via your unique link to the Annual Meeting that will be emailed to you or your proxyholder at 9:00 a.m., Eastern Time, on June 14, 2023 if registration was properly submitted.

If you are a shareholder of record and do not vote through the internet, by telephone, by completing the proxy card that may be delivered to you or online during the Annual Meeting, your shares will not be voted.

If you are a non-registered shareholder because your shares are held in “street name”, meaning they are held for your account by an intermediary, such as a broker, bank or other nominee, then your intermediary that actually holds the shares for you is the record holder and is required to vote the shares it holds on your behalf according to your instructions. You will receive the proxy materials, as well as voting and revocation instructions, from your

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intermediary or its agent. You may vote your shares at the meeting by proxy by following the instructions that your broker, bank or other nominee provides you. If you wish to vote your shares virtually at the Annual Meeting, you must:

If you do not give instructions to your broker, bank or other nominee, and your intermediary does not have discretionary authority to vote the non-registered shareholder’s shares on the matter, or elects not to vote in the absence of instructions from the non-registered shareholder, no votes will be cast on your behalf with respect to such item (a “broker non-vote”). If you are a non-registered shareholder whose common shares are held of record by a broker authorized to trade on Nasdaq, Nasdaq rules permit your broker to exercise discretionary voting authority with respect to certain “discretionary” items. The appointment of PricewaterhouseCoopers LLP as our independent registered public accounting firm (Proposal 2) is considered a discretionary item under such rules. All of the other matters being put to a vote are “non-discretionary” items. Accordingly, under Nasdaq rules your broker may not vote your shares with respect to these other matters.

If you have not completed the steps outlined above, you may still attend the meeting as a guest. However, you will not be able to vote your shares at the meeting.

Since the Annual Meeting will take place virtually, the process for appointing another person as your proxyholder (other than the board nominated proxies named in the proxy card) to access the Annual Meeting and vote on your behalf is different than it would be for an in-person meeting. If you would like your proxyholder to attend and vote at the virtual Annual Meeting on your behalf, you must:

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Upon completing your registration, your proxyholder will receive instructions via email, including a unique link that will allow your proxyholder to access the meeting and will permit your proxyholder to submit questions. Your proxyholder may attend the Annual Meeting virtually and vote online by logging into the virtual meeting platform using the unique link provided to them via email.

If your shares are held in “street name” and you are a non-registered shareholder, you may submit new voting instructions with a later date by contacting your broker, bank or other nominee. You must provide any new voting instructions prior to the deadline specified by your intermediary to ensure your shares are voted in the way you prefer.

You may:

The Company does not expect there will be more nominees for director than positions to be filled. However, should that occur, the nine nominees for director who receive the highest number of votes FOR election will be elected as directors. “Broker non-votes” will not be included in the vote tally for the election of directors and will not affect the results of the vote.

Proposal 2—Appointment of Our Independent Registered Public Accounting Firm

The affirmative vote of the holders of common shares representing a majority of the votes cast on the matter is required to appoint PricewaterhouseCoopers LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2023.

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Shares which abstain from voting and “broker non-votes” with respect to a matter will not be counted as votes in favor of such matter, and will also not be counted as shares voting on such matter. Accordingly, abstentions and “broker non-votes” will have no effect on the voting on the proposals referenced above.

FOR the election of each director; and

FOR the appointment of PricewaterhouseCoopers LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2023.

If you appoint the persons we have designated in the proxy card as your proxyholder, your shares will be voted for, against or withheld from voting in accordance with your instructions on any ballot that may be called for and, if no instructions are provided will be voted as recommended by the board of directors.

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OWNERSHIP OF OUR COMMON SHARES

Unless otherwise provided below, the following table sets forth information regarding beneficial ownership of our common shares as of February 17, 2023 by:

Beneficial ownership is determined in accordance with SEC rules. These rules generally attribute beneficial ownership of securities to persons who possess sole or shared voting power or investment power with respect to those securities and include common shares issuable upon the exercise of stock options that are immediately exercisable or exercisable within 60 days after February 17, 2023. Except as otherwise indicated, all of the shares reflected in the table are common shares and all persons listed below have sole voting and investment power with respect to the shares beneficially owned by them, subject to applicable community property laws. The information is not necessarily indicative of beneficial ownership for any other purpose.

The column entitled “Percentage of Shares Beneficially Owned” is based on a total of 62,724,555 of our common shares outstanding as of February 17, 2023. Except as otherwise indicated in the footnotes below, the address of the beneficial owner is c/o Fusion Pharmaceuticals, Inc., 270 Longwood Road South, Hamilton, Ontario. Canada L8P 0A6.

* Represents beneficial ownership of less than 1% of our outstanding common shares.

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PROPOSAL 1

ELECTION OF DIRECTORS

Our board of directors is elected each year at the annual meeting of shareholders. Each director elected to hold office will do so until the 2024 annual meeting of shareholders (the “2024 Annual Meeting”) and until his or her successor is elected and qualified, or until such director’s earlier death, resignation or removal.

The board of directors, upon the recommendation of the nominating and corporate governance committee, has nominated Donald Bergstrom, M.D., Ph.D., Pablo Cagnoni, M.D., Johan Christenson, M.D., Ph.D., Barbara Duncan, Steve Gannon, Philina Lee, Ph.D., Chau Khuong, Heather Preston, M.D., and John Valliant, Ph.D. for election as a director. Each person nominated for election to our board of directors is currently serving as a director of Fusion.

Each nominee has agreed to serve if elected, and we do not know any reason why any nominee would be unable to serve. In the event that any nominee should be unavailable for election, proxies will be voted for the election of a substitute nominee designated by the board of directors or for election of only the remaining nominees.

Unless authority to do so is withheld, shares represented by executed proxies will be voted for the election of the nine nominees named below. Proxies cannot be voted for a greater number of persons than the number of nominees standing for election.

Vote Required

The election of directors requires a majority vote of our common shares present in person or by proxy at the Annual Meeting and entitled to vote thereon to be approved. Broker non-votes will have no effect on this proposal.

OUR BOARD OF DIRECTORS UNANIMOUSLY RECOMMENDS THAT THE SHAREHOLDERS VOTE “FOR” THE ELECTION OF EACH DIRECTOR NOMINEE TO SERVE UNTIL THE 2024 ANNUAL MEETING.

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DIRECTOR BIOGRAPHIES

Below are the names, ages and certain other information for each member of the board. Information with respect to the number of common shares beneficially owned by each director as of April 27, 2023 appears above under the heading “Ownership of Our Common Shares.” There are no familial relationships among any of our directors, nominees for director and executive officers. In addition to the detailed information presented below for each of our directors, we also believe that each of our directors is qualified to serve on our board and has the integrity, business acumen, knowledge and industry experience, diligence, freedom from conflicts of interest and the ability to act in the interests of our shareholders.

Donald Bergstrom, M.D., Ph.D., age 51, has served as a member of our board of directors since April 2021. Since April 2018, Dr. Bergstrom has served as President of Research and Development at Relay Therapeutics, Inc., a publicly-traded clinical-stage precision medicines company deploying cutting-edge experimental and computational tools to discover medicines against intractable targets. Prior to joining Relay Therapeutics in 2018, Dr. Bergstrom was Chief Medical Officer at Mersana Therapeutics, Inc., a publicly-traded clinical-stage biopharmaceutical company discovering and developing novel antibody-drug-conjugates for the treatment of cancer, from January 2014 through March 2018. Prior to Mersana, Dr. Bergstrom was Global Head of Translational Medicine at Sanofi Oncology from May 2010 to January 2014. Prior to Sanofi, he held roles of increasing responsibility in oncology translational medicine and early clinical development at Merck Research Laboratories. Dr. Bergstrom currently serves on the board of directors of Cellectus S.A., a clinical-stage biopharmaceutical public company. Dr. Bergstrom holds an M.D. and a Ph.D. from the University of Washington, Seattle and a B.A. from the Johns Hopkins University. Dr. Bergstrom resides in the United States. We believe Dr. Bergstrom is qualified to serve on our board of directors because of his experience in the biotechnology industry.

Pablo Cagnoni, M.D., age 60, has served as a member of our board of directors since December 2019. Since November 2022, Dr. Cagnoni has served as Chief Executive Officer of Laronde, a Flagship Pioneering Company, and Executive Partner at Flagship Pioneering, the bioplatform innovation company. Prior to joining Laronde and Flagship, he was Chief Executive Officer of Rubius Therapeutics, Inc., a biotechnology company, from June 2018 until November 2022 where he remains Chairman of the Board of Directors. From May 2015 until June 2018, Dr. Cagnoni served as President and Chief Executive Officer of Tizona Therapeutics, Inc., a privately held biotechnology company, and as a member of its board of directors from May 2015 to March 2021. Dr. Cagnoni previously served as President of Onyx Pharmaceuticals, Inc., a biopharmaceutical company, from October 2013 to April 2015 and Executive Vice President, Global Research and Development and Technical Operations from March 2013 to October 2013. Prior to Onyx, Dr. Cagnoni was Senior Vice President and Global Head of Clinical Development at Novartis Oncology from October 2009 to March 2013. From 2007 to 2009, Dr. Cagnoni was Senior Vice President and Chief Medical Officer at Allos Therapeutics (acquired by Spectrum Pharmaceuticals) and, prior to that, Chief Medical Officer of OSI Pharmaceuticals (acquired by Astellas Pharma Inc.). Dr. Cagnoni has previously served as a member of the board of directors of CRISPR Therapeutics AG, Harpoon Therapeutics, Inc. and Tango Therapeutics, Inc. Dr. Cagnoni received an M.D. from the University of Buenos Aires School of Medicine and completed post-doctoral work in Hematology and Oncology at the Mount Sinai Medical Center in New York and in Stem Cell Transplantation at the University of Colorado Health Sciences Center. Dr. Cagnoni resides in the United States. We believe Dr. Cagnoni is qualified to serve on our board of directors because of his experience in the biotechnology industry.

Johan Christenson, M.D., Ph.D., age 64, has served as a member of our board of directors since February 2017. Dr. Christenson is a Partner of HealthCap Advisor AB. Prior to joining HealthCap Advisor AB in 2001, Dr. Christenson was with SEB Företagsinvest (the venture capital arm of SEB) to supervise its healthcare portfolio. He has senior management experience from Astra Pain Control as Project Director and AstraZeneca as Global Product Director and member of the global therapy area management team of pain and inflammation. Dr. Christenson previously served as a member of the directors of Aprea Therapeutics, Inc., a clinical-stage oncology company from October 2019 to November 2021. Dr. Christenson received his medical training at the Karolinska Institute and received his Ph.D. in Neuroscience in 1991. He served as a lecturer in Neuroscience and also held a position as Assistant Dean at the Karolinska Institute Graduate School for two years. Dr. Christenson resides in Sweden. Dr. Christenson has four years of clinical specialist training in pediatrics and pediatric neurology. We believe that Dr. Christenson is qualified to serve on our board of directors because of his extensive investment experience in the life sciences industry.

Barbara Duncan, age 58, has served as a member of our board of directors since November 2020. Ms. Duncan served at Intercept Pharmaceuticals, Inc. as Chief Financial Officer and Treasurer from May 2009 to June 2016. Prior to Intercept, Ms. Duncan served as Chief Financial Officer of DOV Pharmaceutical, Inc. from 2001 to 2006 and as its Chief Executive

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Officer and a member of its Board of Directors from 2007 to 2009. Ms. Duncan serves on the board of directors of Halozyme Therapeutics, Inc. since February 2023, Atea Pharmaceuticals, Inc. since November 2020, Jounce Therapeutics, Inc. since June 2016, Adaptimmune Therapeutics plc since June 2016, and Ovid Therapeutics, Inc. since June 2017. Previously, Ms. Duncan served on the boards of directors of Immunomedics, Inc. from March 2019 to October 2020, Innoviva, Inc., from November 2016 through April 2018, ObsEva S.A. from November 2016 to May 2019 and Aevi Genomic Medicine, Inc., from June 2015 through January 2020. Ms. Duncan received her B.A. from Louisiana State University and her M.B.A. from the Wharton School, University of Pennsylvania. Ms. Duncan resides in the United States. We believe Ms. Duncan is qualified to serve on our board of directors due to her experience in the biotechnology industry and with public companies.

Steve Gannon, CA/CPA, age 61, has served as a member of our board of directors since January 2020. Mr. Gannon has served on the board of directors of Xenon Pharmaceutics Inc., a biotechnology company, since May 2015, the board of directors of enGene Inc., a biotechnology company, since February 2017, the board of directors of Laborie Médical Technologies, a private Medtech company, since 2016, Alta Sciences, a private research services company, since April 2021, and AeroGen, a private Medtech company, from November 2018 to July 2020. From June 2014 to March 2018, Mr. Gannon served on the board of directors of Advanced Accelerator Applications SA, a healthcare company acquired by Novartis in January 2018. Mr. Gannon was Chief Financial Officer, Senior Vice President of Finance and Treasurer at Aptalis Pharma Inc. until February 2014, after which it was sold to Forest Laboratories. Prior to joining Aptalis in 2006, Mr. Gannon served as the Chief Financial Officer for Cryocath Technologies Inc. from 1999 to 2006, as the Director of Finance and Administration of the Research Division of AstraZeneca Canada Inc. from 1996 to 1999, and as the Chief Financial Officer of Mallinckrodt Medical Inc.’s Canadian operations from 1989 to 1995. He received a BComm in Accounting and Business Systems from Concordia University in Montreal, Canada in 1983, and completed the Executive Program at the Richard Ivey School of Business at the University of Western Ontario in Ontario, Canada in 1995. He has been a Chartered Accountant since 1985. Mr. Gannon resides in Canada. We believe that Mr. Gannon is qualified to serve on our board of directors because of his financial expertise and senior management expertise in the pharmaceutical industry.

Chau Q. Khuong, age 47, has served as a member of our board of directors since March 2019. Mr. Khuong is a biotechnology entrepreneur and venture capital investor. He served as a Private Equity Partner at OrbiMed from 2003 until his retirement in August 2021. Mr. Khuong currently serves as a director of two publicly traded life sciences companies: Galecto, Inc. since October 2018 and NextCure, Inc. since December 2015, and previously served as a director of Aerpio Pharmaceuticals, Inc., BELLUS Health Inc., Inspire Medical Systems, Inc., Nabriva Therapeutics plc (formerly Nabriva Therapeutics AG), Otonomy, Inc., Synlogic, Inc. from, and as chairman of the board of directors of Pieris Pharmaceuticals, Inc.. Mr. Khuong received a B.S. in Molecular Biology with a concentration in Biotechnology and a M.P.H. with a concentration in Infectious Diseases from Yale University. Mr. Khuong resides in the United States. We believe that Mr. Khuong is qualified to serve as a member of our board of directors due to his extensive directorship and healthcare industry experience.

Philina Lee, Ph.D., age 46, has served as a member of our board of directors since February 2021. Dr. Lee currently serves as Chief Commercial Officer at Blueprint Medicines Corporation, a publicly traded global precision therapy company. Since joining Blueprint Medicines in 2014, Dr. Lee has served in positions of increasing responsibility, including most recently as Senior Vice President and Head of Portfolio Strategy until April 2022. Prior to joining Blueprint Medicines, Dr. Lee served as Head of U.S. Marketing at Algeta ASA, where she contributed to building the fully integrated organization that successfully launched Xofigo® (radium-223 dichloride), a first in class alpha-emitting radiopharmaceutical. Algeta was acquired by Bayer AG in 2014. Prior to Algeta, Dr. Lee held oncology marketing roles at Sanofi and Genzyme, and was a Healthcare Strategy Consultant at Health Advances. Dr. Lee does not currently serve on any other public company board of directors. Dr. Lee holds a Ph.D. from the Massachusetts Institute of Technology and a B.S. from the University of Alberta. Dr. Lee resides in the United States. We believe that Dr. Lee is qualified to serve as a member of our board of directors due to her extensive healthcare industry experience.

Heather Preston, M.D., age 57, has been a member of our board of directors since March 2019. Dr. Preston has served as a Managing Partner at Pivotal bioVenture Partners, a venture capital firm, and as a Senior Advisor at TPG Biotech, a biotechnology venture capital firm, since July 2018. Dr. Preston was previously a Partner and Managing Director at TPG Biotech from May 2005 to July 2018. Dr. Preston currently serves on the board of directors of Oxford BioMedica PLC. Dr. Preston also served on the board of directors of Akouos, Inc. until acquired by Eli Lilly and Company in December 2022, the board of directors of Entasis Therapeutics Holdings, Inc. until acquired by Innoviva, Inc. in July 2022, the board of directors of Alder Biopharmaceuticals, Inc. until acquired by Lundbeck A/S in October 2019, the board of directors of Albireo Pharma, Inc. from 2008 to 2018, and the board of directors of Otonomy, Inc. from January 2010 until February 2020. Dr.

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Preston received her M.D. from the University of Oxford and a BS in Biochemistry from the University of London. Dr. Preston resides in the United States. We believe that Dr. Preston is qualified to serve on our board of directors because of her extensive experience in the biopharmaceutical investment industry and her scientific background.

John Valliant, Ph.D., age 53, is our founder and has served as Chief Executive Officer and as a member of our board of directors since December 2014. From March 2008 to October 2018, Dr. Valliant was the Chief Executive Officer at the Centre for Probe Development and Commercialization, (the “CPDC”), a radiopharmaceutical research and development center, which he also founded. Since 1999, Dr. Valliant has also served as a Professor in the Department of Chemistry and Chemical Biology at McMaster University. Dr. Valliant completed his Ph.D. at McMaster University, and also completed a post-doctoral fellowship under the joint supervision of professors Alun G. Jones of Harvard Medical School and Alan Davison of the Massachusetts Institute of Technology. Dr. Valliant resides in Canada. We believe that Dr. Valliant is qualified to serve on our board of directors because of his considerable qualifications, attributes and skills, including his distinguished scientific background and experience in leadership roles in the biopharmaceutical industry.

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DIRECTOR COMPENSATION

Under our director compensation program, we pay our non-employee directors both cash and equity retainers. During fiscal year 2022, John Valliant, Ph.D., our Chief Executive Officer, served as a member of our board of directors, as well as an employee, and received no additional compensation for his services as a director. See the section entitled “Executive Compensation” for more information about Dr. Valliant’s compensation for fiscal year 2022.

Each non-employee director receives a cash retainer for service on the board of directors and for service on each committee of which the director is a member. The chairperson of the board and of each committee receives a higher retainer for such service. These fees are payable quarterly in arrears. The fees paid in 2022 to non-employee directors for service on the board of directors and for service on each committee of the board of directors on which the director is a member were as follows:

For 2022, the annual board of directors fee was increased from $35,000 (which was in effect in 2021) to $40,000. No other changes were made to the fees paid for service on our board of directors in 2022 or any committee thereof.

Under our director compensation program, upon their initial election to the board of directors, each non-employee director receives an option to purchase 34,000 common shares, which initial option vests ratably in 36 equal monthly installments, subject to continued service as a director through the applicable vesting dates, and becomes exercisable in full upon a change in control of our company. Further, on the date of the first board meeting held after each annual meeting of shareholders, each non-employee director receives an option to purchase 17,000 common shares. Each of these options vests on the earlier of: (i) the first anniversary of the grant date or the next annual meeting of shareholders, or (ii) upon a change in control of our company, both subject to the non-employee director’s continued service as a director. The exercise price of these options equals the fair market value of our common shares on the date of grant.

This program is intended to provide a total compensation package that enables us to attract and retain qualified and experienced individuals to serve as directors and to align our directors’ interests with those of our shareholders.

We reimburse our non-employee directors for reasonable travel and out-of-pocket expenses incurred in connection with attending board of director and committee meetings. The following table sets forth information regarding compensation earned by our non-employee directors during the year ended December 31, 2022.

Director Compensation for 2022

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CORPORATE GOVERNANCE

General

We believe that good corporate governance is important to ensure that our company is managed for the long-term benefit of our shareholders. We periodically review our corporate governance policies and practices and compare them to those suggested by various authorities in corporate governance and the practices of other public companies. As a result, we have adopted policies and procedures that we believe are in the best interests of our company and our shareholders.

Corporate Governance Guidelines

Our corporate governance guidelines assist our board of directors in the exercise of its duties and responsibilities and to serve the best interests of our company and our shareholders. These guidelines, which provide a framework for the conduct of our board’s business, provide that:

Our board of directors is responsible for managing or supervising the management of our business and affairs. This includes appointing our chief executive officer, advising management on strategic issues, approving our business and other plans and monitoring our performance against those plans and against our operating and capital budgets. In addition, our board also receives and considers recommendations from our various committees with respect to matters such as the following:

Our board of directors does not have a written mandate.

Code of Business Conduct and Ethics

We have also adopted a written code of business conduct and ethics that applies to our directors, officers and employees, including our principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions. A copy of the code is posted on the “Investors & Media— Corporate Governance” section of our website, which is located at https://ir.fusionpharma.com/documents-charters. If we make any substantive amendments to, or grant any waivers from, the code of business conduct and ethics for any officer or director, we will disclose the nature of such amendment or waiver on our website or in a Current Report on Form 8-K to be filed with the SEC and will file a copy of any amendment with Canadian securities regulators on www.sedar.com. Employees are required to annually certify compliance with the code.

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Removal of Directors

The Canada Business Corporation Act (the “CBCA”) provides that our directors may be removed by the affirmative vote of the holders of at least a majority of the votes cast at an annual or special meeting of our shareholders, and that certain vacancies on our board of directors, including a vacancy resulting from an enlargement of our board of directors that is permitted by the CBCA, may be filled by a quorum of our directors. In accordance with the terms of the Articles of the Corporation (as amended, the “articles”), and our general by-laws (as amended, the “by-laws”), we expect that our board of directors will be elected to hold office until the next annual shareholders meeting.

Advance Notice Provisions

Our by-laws provide that, subject to the CBCA and the articles, only persons who are nominated in accordance with our “advance notice” provisions will be eligible for election as directors at any annual meeting of our shareholders, or at any special meeting if one of the purposes for which the special meeting was called was election of directors. These provisions are intended to: (1) facilitate orderly and efficient annual general meetings or, where the need arises, special meetings; (2) ensure that all our shareholders receive adequate notice of board nominations and sufficient information with respect to all nominees; and (3) allow our shareholders to vote on an informed basis.

Under our advance notice provisions, a shareholder wishing to nominate a director would be required to provide us with notice, in a prescribed form and within prescribed time periods as specified in our by-laws. These time periods include, (1) in the case of an annual meeting of shareholders, not less than 30 days prior to the date of the annual meeting of shareholders; provided that if the first public announcement of the date of the annual meeting of shareholders, the Notice Date, is less than 50 days before the meeting date, not later than the close of business on the 10th day following the Notice Date, and (2) in the case of a special meeting (which is not also an annual meeting) of shareholders called for any purpose which includes electing directors, not later than the close of business on the 15th day following the Notice Date; provided that, in either instance, if “notice-and-access” provisions under applicable Canadian laws are used for delivery of proxy related materials in respect of a meeting described above, and the notice date in respect of the meeting is not less than 50 days prior to the date of the applicable meeting, the notice must be received not later than the close of business on the 40th day before the applicable meeting.

A shareholder wishing to nominate a director must provide notice to our corporate secretary by email (at such email address that is set in our issuer profile on the System for Electronic Document Analysis and Retrieval (“SEDAR”) at www.sedar.com) or by personal delivery at Fusion Pharmaceuticals Inc., 270 Longwood Road South, Hamilton, Ontario, Canada L8P 0A6.

Determination of Independence

Our board of directors has determined that each of our directors, with the exception of Dr. Valliant, who serves as our Chief Executive Officer, is an “independent director” within the meaning of the director independence standards established by the SEC and the Nasdaq Stock Market (“Nasdaq”) and Canadian securities laws. Our board of directors also determined that Steve Gannon, Chau Khuong and Heather Preston, M.D. who comprise our audit committee, Pablo Cagnoni, M.D., Steve Gannon and Heather Preston, M.D., who comprise our compensation committee, and Barbara Duncan, Chau Khuong and Philina Lee, who comprise our nominating and corporate governance committee, satisfy the independence standards for such committees established by the SEC, the Nasdaq, and Canadian securities laws, as applicable. In making such determinations, our board of directors evaluated, and will evaluate at least on an annual basis, all relationships that each such non-employee director has with our company in light of all facts and circumstances our board of directors deemed relevant in determining independence, including the beneficial ownership of our common shares by each non-employee director.

The non-management directors meet at regularly scheduled executive sessions without management participation, and at least twice each year an executive session with only independent directors present is held. In 2022, there were seven executive sessions at which only the independent directors were present.

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Board Self-Assessment; Director Candidates; and Criteria

Our board performs an annual self-assessment. During this self-assessment, the board considers many factors, including, but not limited to, the expertise of existing board members and the expertise of directors we need in our transition from a clinical development stage company to becoming a commercial enterprise. The board’s annual self-assessment is conducted by a written survey in which each director is asked to comment on the effectiveness and contribution of the board as a whole. The assessment of this potential expertise consists of a review of the business expertise of our current directors.

Our board of directors is responsible for selecting its own members. The board of directors delegates the selection and nomination process to our nominating and corporate governance committee, with the expectation that other members of the board of directors, and of management, will be requested to take part in the process as appropriate.

Generally, our nominating and corporate governance committee identifies candidates for director nominees in consultation with management, through the use of independent director search firms, through recommendations submitted by shareholders or through such other methods as the nominating and corporate governance committee deems to be helpful to identify candidates. Once candidates have been identified, the nominating and corporate governance committee confirms that the candidates meet the minimum qualifications for director nominees established by the nominating and corporate governance committee. These criteria include the candidate’s personal and professional ethics and integrity, achievement and competence in our field and ability to exercise sound business judgment, skills that are complementary to those of our existing board of directors, ability to assist and support management and make significant contributions to our success, and an understanding of the fiduciary responsibilities that are required of a director and the and the ability to act in the interests of all shareholders.

The nominating and corporate governance committee may gather information about the candidates through meetings from time to time, questionnaires or background checks to evaluate biographical information and background material relating to potential candidates, and interviews of selected candidates by members of the committee and our board. The nominating and corporate governance committee then meets as a group to discuss and evaluate the qualities and skills of each candidate, both on an individual basis and taking into account the overall composition and needs of our board of directors. Based on the results of the evaluation process, the nominating and corporate governance committee recommends candidates for the board of directors’ approval as director nominees for election to the board of directors.

The board does not believe that limits on the number of consecutive terms a director may serve or on the directors’ ages are appropriate at this stage. Instead, each director’s performance and their continued service is assessed by the nominating and corporate governance committee in light of the needs of the board of directors and other relevant factors.

Shareholders may recommend individuals to our nominating and corporate governance committee for consideration as potential director candidates by providing timely notice and meeting the other requirements set forth in our by-laws, including our advanced notice provision, and the rules and regulations of the SEC, applicable Canadian securities laws and the CBCA. Assuming such requirements have been met, the nominating and corporate governance committee will evaluate shareholder-recommended candidates by following substantially the same process, and applying substantially the same criteria, as it follows for candidates submitted by others. If the board determines to nominate a shareholder-recommended candidate and recommends his or her election, then his or her name will be included in our proxy card for the next annual meeting.

Shareholders also have the right under our bylaws to directly nominate director candidates, without any action or recommendation on the part of the committee or our board, by following the procedures set forth under “Shareholder Proposals for the 2024 Annual Meeting.”

The company conducts an orientation program for each new director, which generally includes conversations with individual members of management. The orientation is designed to familiarize the new director with the company’s business and strategic plans, key policies and practices, principal officers and management structure, auditing and compliance processes and its code of business conduct and ethics. New directors have access to historical published information about the company, its articles and by-laws, the corporate governance guidelines and the charters of the board’s committees and other relevant information. The nominating and corporate governance committee is responsible for providing materials or

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briefing sessions for continuing directors on topics that will assist them in discharging their duties. In addition, management makes regular presentations to the Board on the main areas of the company’s business and new developments in the industry.

Board Diversity

Our nominating and corporate governance committee has a written board diversity policy and believes that our board, taken as a whole, should embody a diverse set of skills, experience, knowledge and backgrounds, including an appropriate number of women directors. The board has not adopted targets for the number or proportion of female directors as the company is committed to a merit-based system for board composition, which reflects a diverse and inclusive culture where directors believe that their views are heard, their concerns are attended to and they serve in an environment where bias, discrimination and harassment on any matter are not tolerated. When identifying suitable candidates for appointment to the board, the company considers candidates on merit against objective criteria and the needs of the board and considers the need to increase the number of women directors on the board to meet the company’s goal. When recruiting new candidates for appointment, search protocols will go beyond the networks of existing board members and will incorporate diversity, including identification of female candidates, as a component. Any search firm engaged to assist the board or the nominating and corporate governance committee in identifying candidates for appointment to the board shall be directed to include women candidates and women candidates will be included in the board’s evergreen list of potential board nominees.

The company has not adopted targets for the number or proportion of directors who are members of a visible minority, Indigenous peoples or persons with a disability (the “designated groups”) or for other diversity characteristics at this time. For now, the board has chosen to focus on gender in exclusion to other diversity characteristics and the nominating and corporate governance committee does not specifically consider the level of representation of members of designated groups on the board in identifying and nominating candidates for election or re-election to the board. If all nominees proposed for election for the meeting are elected, there will be three women on the Board, representing 33% of the directors.

The below board diversity matrix reports self-identified diversity statistics for the board.

Board Diversity Matrix (As of April 27, 2023)

The company does not consider the level of representation of women or other designated groups in executive officer positions and has not adopted targets for the number or proportion of directors who are women or members of other designated groups as the company seeks to promote individuals solely based on merit. Currently two (or 25%) of the executive officers are women, none (or 0%) of the executive officers are visible minorities and none (or 0%) of the executive officers are Indigenous peoples or persons with a disability.

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Communication from Shareholders

The board will give appropriate attention to written communications that are submitted by shareholders and will respond if and as appropriate. The chairman of the board of directors is primarily responsible for monitoring communications from shareholders and for providing copies or summaries to the other directors as he considers appropriate.

Communications are forwarded to all directors if they relate to important substantive matters and include suggestions or comments that the chairman of the board considers to be important for the directors to know. In general, communications relating to corporate governance and corporate strategy are more likely to be forwarded than communications relating to ordinary business affairs, personal grievances and matters as to which we receive repetitive or duplicative communications.

Board and Committee Meetings

Our board of directors held eight meetings during 2022. During 2022, each of the directors then in office attended at least 75% of the aggregate of all meetings of the board of directors and all meetings of the committees of the board of directors on which such director then served. A director’s attendance rate is considered by the nominating and corporate governance committee when making recommendations for re-appointment of the director. Continuing directors and nominees for election as directors in a given year are required to attend the annual meeting of shareholders, barring significant commitments or special circumstances. Fusion held a 2022 annual meeting of shareholders. The board meeting attendance record for each director who served at the end of 2022 is as follows:

Our board has established an audit committee, a compensation committee and a nominating and corporate governance committee. Each of these committees operates under a charter that has been approved by our board of directors. A copy of each charter can be found under the “Investors & Media—Corporate Governance” section of our website, which is located at www.fusionpharma.com. The board has not adopted position descriptions for the chairperson of each committee. However, each committee chairperson understands that the responsibilities of the committee chairperson include responsibility for providing leadership to the committee, including chairing meetings in a manner that facilitates open discussions and expressions of competing views, and reporting to the board on the work of the committee and any recommendations for approval by the board. The committee chairperson also ensures that the committee receives the information required for the performance of its responsibilities. In March 2021, our board of directors also established a research and development committee to assist the board in its oversight of our research and development activities.

Audit Committee

The audit committee, which has been established in accordance with Section 3(a)(58) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), currently consists of Steve Gannon, Chau Khuong and Heather Preston, M.D. Mr. Gannon is the chair of the audit committee. Our board of directors has determined that each member of the audit committee meets the independence requirements established by the SEC, the applicable listing standards of Nasdaq and applicable Canadian laws. Our board of directors has determined that Mr. Gannon qualifies as an “audit committee financial expert” within the meaning of SEC regulations. Our audit committee assists our board of directors in its oversight of our accounting

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and financial reporting process and the audits and quarterly reviews of our financial statements. We currently do not have an internal audit function. The audit committee held four meetings during 2022. The audit committee’s responsibilities include:

All audit services to be provided to us and all non-audit services, other than de minimis non-audit services, to be provided to us by our independent registered public accounting firm must be approved in advance by our audit committee.

Compensation Committee

The current members of our compensation committee are Pablo Cagnoni, M.D., Steve Gannon and Heather Preston, M.D. Dr. Cagnoni is the current chair of the compensation committee. Our compensation committee assists our board of directors in the discharge of its responsibilities relating to the compensation of our executive officers. The compensation committee held five meetings and acted by written consent sixteen times during 2022. The compensation committee’s responsibilities include:

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Our Compensation Committee makes most of the significant adjustments to annual compensation, determines bonus and equity awards and establishes new performance objectives. However, our Compensation Committee also considers matters related to individual compensation, such as compensation for new executive hires, as well as high-level strategic issues, such as the efficacy of the Company’s compensation strategy, potential modifications to that strategy and new trends, plans or approaches to compensation. Generally, the Compensation Committee’s process comprises two related elements: the determination of compensation levels and the establishment of performance objectives for the current year. For executives other than the Chief Executive Officer, our Compensation Committee solicits and considers evaluations and recommendations submitted to the Compensation Committee by the Chief Executive Officer. In the case of the Chief Executive Officer, the evaluation of his performance is conducted by the Compensation Committee, which determines any adjustments to his compensation as well as awards to be granted. For all executives and directors, as part of its deliberations, the Compensation Committee may review and consider, as appropriate, materials such as financial reports and projections, operational data, tax and accounting information, tally sheets that set forth the total compensation that may become payable to executives in various hypothetical scenarios, executive and director share ownership information, company stock performance data, analyses of historical executive compensation levels and current company-wide compensation levels and analyses of executive and director compensation paid at a peer group of other companies approved by our Compensation Committee. In 2022, the Compensation Committee retained the services of Pay Governance LLC (“Pay Governance”), as its external, independent compensation consultant and considered Pay Governance’s input on certain compensation matters as they deemed appropriate.

Nominating and Corporate Governance Committee

The current members of our nominating and corporate governance committee are Barbara Duncan, Philina Lee, Ph.D. and Chau Khuong. Ms. Duncan is the chair of the nominating and corporate governance committee. The nominating and corporate governance committee held three meetings during 2022. The nominating and corporate governance committee’s responsibilities include:

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Research and Development Committee

The current members of our research and development committee are Donald Bergstrom, M.D., Pablo Cagnoni, M.D., Johan Christenson, M.D., Ph.D. and Philina Lee, Ph.D. Dr. Bergstrom is the chair of the research and development committee. The research and development committee held four meetings during 2022. The research and development committee’s responsibilities include:

Our board of directors may from time to time establish other committees.

Limitations on Liability and Indemnification Agreements

We are governed by the CBCA. Under the CBCA, and under our by-laws, we may (or must, in the case of our by-laws) indemnify our current or former directors and officers or any other individuals who act or have acted at our request as a director or officer of a related entity, against all costs, charges and expenses, including an amount paid to settle an action or satisfy a judgment, reasonably incurred by such individual in respect of any civil, criminal, administrative, investigative or other proceeding in which such individual is involved because of his or her association with us or a related entity. The CBCA also provides that we may also make an advance payment to such individual for costs, charges and expenses reasonably incurred in connection with such a proceeding, provided, however, that such individual shall repay such payment if he or she does not fulfill the conditions described below. The CBCA also provides that we may, with the approval of the court, indemnify the individual or make an advance payment in respect of certain derivative actions by or on behalf of us or the other entity to procure a judgement in our or its favor.

Indemnification is prohibited under the CBCA unless the individual:

The CBCA also provides that the individual is entitled to indemnification from us in respect of all costs, charges and expenses reasonably incurred by the individual in connection with the defense of any civil, criminal, administrative, investigative or other proceeding to which the individual is subject because of his or her association with us or a related entity if the individual (i) was not judged by the court or other competent authority to have committed any fault or omitted to do anything that the individual ought to have done, and (ii) fulfils the conditions described above.

The CBCA and our by-laws authorize us to purchase and maintain insurance for the benefit of each of our current or former directors or officers and other agents and each person who acts or acted at our request as a director, officer or other agent or an individual acting in a similar capacity, of another entity.

In addition, we have entered into separate indemnity agreements with each of our directors and officers pursuant to which we agree to indemnify and hold harmless our directors and officers against any and all liability, loss, damage, cost or expense in accordance with the terms and conditions of the CBCA and our by-laws.

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We maintain a directors’ and officers’ insurance policy pursuant to which our directors and officers are insured against liability for actions taken in their capacities as directors and officers. We believe that these provisions in our by-laws and these indemnity agreements are necessary to attract and retain qualified persons as directors and officers. There is no pending litigation or proceeding naming any of our directors or officers as to which indemnification is being sought, nor are we aware of any pending or threatened litigation that may result in claims for indemnification by any director or officer.

Insofar as indemnification for liabilities arising under the Securities Act of 1933, as amended (the “Securities Act”), may be permitted to our directors, officers and controlling persons pursuant to the foregoing provisions, or otherwise, we have been advised that, in the opinion of the SEC, such indemnification is against public policy as expressed in the Securities Act, and is, therefore, unenforceable.

Compensation Committee Interlocks and Insider Participation

For the 2022 fiscal year, Pablo Cagnoni, M.D., Steve Gannon and Heather Preston, M.D., served as members of our Compensation Committee. None of our executive officers serves, or in the past has served, as a member of the board of directors or compensation committee, or other committee serving an equivalent function, of any entity that has one or more executive officers who serve as members of our board of directors or our compensation committee. None of the members of our compensation committee is an officer or employee of our company, nor have they ever been an officer or employee of our company.

Board Leadership Structure

Our board of directors is currently chaired by Barbara Duncan, an independent director. Currently, the role of chairman of the board of directors is separated from the role of chief executive officer. Separating these positions allows our chief executive officer to focus on our day-to-day business, while allowing the chairperson of the board to lead the board of directors in its fundamental role of providing advice to and independent oversight of management. The board has not adopted a position description for the chairperson. However, there is a shared understanding on the board of the chairperson’s responsibilities. The chairperson’s primary role is to provide leadership to the board and its committees, including chairing meetings in a manner that facilitates open discussions and expressions of competing views. The chairperson is also responsible for, among other things, assisting the board in obtaining information required for the performance of their duties, retaining appropriately qualified and independent advisors as needed, working with the board to support board development and to ensure a proper committee structure is in place, providing a link between the board and management and acting in an advisory capacity to the chief executive officer in all matters concerning the interests and management of the company. Our board of directors recognizes the time, effort and energy that the chief executive officer must devote to his position in the current business environment, as well as the commitment required to serve as the chairperson of the board, particularly as the board of directors’ oversight responsibilities continue to grow. Our board of directors also believes that this structure ensures a greater role for the non-management directors in the oversight of our company and active participation of the independent directors in setting agendas and establishing priorities and procedures for the work of our board of directors. Our board of directors believes its administration of its risk oversight function has not affected its leadership structure. Although our by-laws do not require our chairperson of the board and chief executive officer positions to be separate, our board of directors believes that having separate positions is the appropriate leadership structure for us at this time. The board has not adopted a separate position description for our chief executive officer. The role and responsibilities of the chief executive officer is delineated by frequent discussion and interaction between the board chairperson and the chief executive officer.

Oversight of Risk

Risk is inherent with every business, and how well a business manages risk can ultimately determine its success. We face a number of risks, including risks relating to our financial condition, development and commercialization activities, operations, strategic direction and intellectual property as more fully discussed under “Risk Factors” in our Annual Report on Form 10-K. Management is responsible for the day-to-day management of risks we face, while our board of directors, as a whole and through its committees, has responsibility for the oversight of risk management. In its risk oversight role, our board of directors has the responsibility to satisfy itself that the risk management processes designed and implemented by management are adequate and functioning as designed.

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Our board of directors regularly discusses with management our major risk exposures, the potential impact of these risks on our business and the steps we take to manage them. The risk oversight process includes receiving regular reports from board committees and members of senior management to enable our board to understand the company’s risk identification, risk management and risk mitigation strategies with respect to areas of potential material risk, including operations, finance, legal, regulatory, strategic and reputational risk.

The audit committee reviews information regarding liquidity and operations, and oversees our management of financial risks. Periodically, the audit committee reviews our policies with respect to risk assessment, risk management, loss prevention and regulatory compliance. Oversight by the audit committee includes direct communication with our external auditors, and discussions with management regarding significant risk exposures and the actions management has taken to limit, monitor or control such exposures. The compensation committee is responsible for assessing whether any of our compensation policies or programs has the potential to encourage excessive risk-taking. The nominating and corporate governance committee manages risks associated with the independence of the board, corporate disclosure practices, and potential conflicts of interest. While each committee is responsible for evaluating certain risks and overseeing the management of such risks, the entire board is regularly informed through committee reports about such risks. Matters of significant strategic risk are considered by our board as a whole.

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CERTAIN RELATIONSHIPS AND RELATED PARTY TRANSACTIONS

Certain Relationships with Related Parties

Other than the compensation agreements and other arrangements described in “Executive Compensation” and elsewhere in this proxy statement and the relationships and transactions described below, since January 1, 2022, there was no transaction or series of transactions to which we were or will be a party in which:

Share Issuance in connection with Rainier Asset Purchase Agreement

In March 2020, we entered into an asset purchase agreement with Rainier Therapeutics, Inc. (f/k/a BioClin Therapeutics, Inc.) (“Rainier”) (as amended, the “APA”) and a share purchase agreement with Rainier (the “SPA”), pursuant to which we acquired substantially all the assets of Rainier. As partial consideration for the transaction, we paid an upfront cash payment of $1.0 million. As a result of the closing of the transaction, in July 2021, we paid an additional $3.5 million and issued 313,359 of our common shares to certain of Rainier’s shareholders, including 22,303 of our common shares to HealthCap IV LP. In the future, we may owe HealthCap IV LP additional cash and equity consideration upon the achievement of specified development and regulatory milestones as set forth in the APA. Dr. Christenson who is a member of our board of directors, serves as a partner of HealthCap Advisor AB, which oversees several funds, including HealthCap IV LP.

Agreements with CPDC

We have entered into a Master Services Agreement and a Supply Agreement with CPDC under which CPDC provides products and services to us, including preclinical and manufacturing services, administrative support services, access to laboratory facilities and laboratory technicians and products for human safety and efficacy clinical trials. In connection with the Supply Agreement, we pay CPDC $0.2 million per quarter, plus fees for production, packaging and distribution of products supplied to us. In connection with the Master Services Agreement, we pay CPDC periodically pursuant to the amounts set forth in each work order. During the years ended December 31, 2021 and 2022, we made payments to CPDC in connection with the services described above of $1.7 million and $1.8 million, respectively. We also entered into a transition services agreement with CPDC on June 1, 2021 in connection with our manufacturing facility in Hamilton, Ontario pursuant to which we have paid the CPDC $2.5 million for services relating to certain aspects of the validation of the manufacturing facility which is currently under construction. John Valliant, our Chief Executive Officer, is the founder and a member of the board of directors of CPDC. In August 2022, CPDC transferred and assigned the Master Services Agreement and the Supply Agreement to a third-party commercial development and manufacturing organization known as AtomVie, which is not a related party. Dr. Valliant received non-voting shares in AtomVie, but has no control over AtomVie nor is in any other way affiliated with AtomVie.

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Policies and Procedures for Related Person Transactions

Our board of directors reviews and approves transactions with directors, officers and holders of five percent or more of our voting securities and their affiliates, each a related party. In connection with our initial public offering, we adopted a formal written policy that our executive officers, directors, holders of more than five percent of any class of our voting securities, and any member of the immediate family of and any entity affiliated with any of the foregoing persons, are not permitted to enter into a related party transaction with us without the prior consent of our audit committee, or other independent members of our board of directors in the event it is inappropriate for our audit committee to review such transaction due to a conflict of interest. Any request for us to enter into a transaction with an executive officer, director, holders of more than five percent of any class of our voting securities, or any of their immediate family members or affiliates, in which the amount involved exceeds $120,000 must first be presented to our audit committee for review, consideration and approval. In approving or rejecting any such proposal, our audit committee will consider the relevant facts and circumstances available and deemed relevant to our audit committee, including, but not limited to, whether the transaction will be on terms no less favorable than terms generally available to an unaffiliated third party under the same or similar circumstances and the extent of the related party’s interest in the transaction. All of the transactions described in this section were entered into prior to the adoption of this policy.

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EXECUTIVE COMPENSATION

Overview

The following discussion contains forward-looking statements that are based on our current plans, considerations, expectations and determinations regarding future compensation programs. The actual amount and form of compensation and the compensation policies and practices that we adopt in the future may differ materially from currently planned programs as summarized in this discussion.

As an “emerging growth company,” we have opted to comply with the executive compensation disclosure rules applicable to “smaller reporting companies,” as such term is defined in the rules promulgated under the Securities Act. This section provides an overview of the compensation awarded to, earned by, or paid to each individual who served as our principal executive officer for the year ended December 31, 2022, or fiscal year 2022, and our next two most highly compensated executive officers in respect of their service to our company for fiscal year 2022. We refer to these individuals as our named executive officers. Our named executive officers for fiscal year 2022 are:

Compensation for our executive officers is composed primarily of the following main components: base salary; bonus; and equity incentives in the form of stock options. Our executive officers, like all full-time employees, are eligible to participate in our health and welfare benefit plans.

Our compensation committee reviews compensation annually for our executive officers. In setting executive base salaries and bonuses and granting equity incentive awards, we consider compensation for comparable positions in the market, the historical compensation levels of our executives, individual performance as compared to our expectations and objectives, our desire to motivate our employees to achieve short- and long-term results that are in the best interests of our shareholders, and a long-term commitment to our company. We target a general competitive position, based on independent third-party benchmark analytics to inform the mix of compensation of base salary, annual incentives or long-term incentives.

Our compensation committee is responsible for approving the compensation for all of our executive officers. Our compensation committee typically reviews and discusses management’s proposed compensation with the Chief Executive Officer for all executives officers other than the Chief Executive Officer. Based on those discussions and its discretion, taking into account the factors noted above, the compensation committee approves the compensation for the executive officers.

Our compensation committee is authorized to retain the services of one or more executive compensation advisors, as it sees fit, in connection with the establishment of our executive compensation programs and related policies. In 2022, the compensation committee retained the services of Pay Governance as its external independent compensation consultant. During 2022, Pay Governance did not provide services to us other than the services to our compensation committee described herein. Our compensation committee performs an annual assessment of its compensation consultants’ independence to determine whether the consultants are independent. Based on its evaluation, the compensation committee has determined that Pay Governance is independent and that its work has not raised any conflicts of interest.

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2022 Summary Compensation Table

The following table presents information regarding the total compensation that was awarded to, earned by or paid to our named executive officers for services rendered during fiscal year 2022.

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Narrative to Summary Compensation Table

The primary elements of compensation for our named executive officers are base salary, bonus, and equity incentives in the form of stock options. These elements (and the amounts of compensation and benefits under each element) were selected because we believe they are necessary to help us attract and retain executive talent in a very competitive market, which is fundamental to our success. Below is a more detailed summary of the current executive compensation program as it relates to our named executive officers.

Annual Base Salary

We use base salaries to recognize the experience, skills, knowledge and responsibilities required of all our employees, including our named executive officers. Our compensation committee and board of directors, in the case of Dr. Valliant, annually reviews base salaries for trends in the market of the salaries paid to public company employees as well as for exogenous factors such as inflation. For the year ended December 31, 2022, the annual base salaries for each of Dr. Valliant, Dr. Burak and Mr. Crowley were reviewed and adjusted upward for merit increases. For the year ending December 31, 2023, the annual base salaries for each of Dr. Valliant, Dr. Burak and Mr. Crowley are $805,543 CAD ($619,172 USD), $624,643 CAD ($480,125 USD) and $478,896, respectively. Drs. Valliant and Burak’s salary increases in local Canadian currency were 4.0% and 4.5% respectively. Due to fluctuations in the twelve-month trailing United States and Canadian dollar exchange rate, in some years Drs. Valliant and Burak’s salaries may appear to decrease rather than increase when compared to the prior year when viewed only in U.S. dollars.

Cash Bonus

We also believe that a significant portion of our executives’ cash compensation should be based on the attainment of business goals established by our board of directors or compensation committee. Each of our named executive officers participated in our Senior Executive Cash Incentive Bonus Plan (the “Bonus Plan”). The Bonus Plan provides for formula-based incentive payments based upon the achievement of certain corporate and individual performance goals and objectives approved by our board of directors and compensation committee, respectively. We typically establish bonus targets for our named executive officers and conduct an annual performance review process to serve as the basis for determining eligibility for any such bonuses. Among the key parameters that typically are the basis for such bonus determinations are our achievement of overall corporate goals and the achievement of specified goals and objectives by each individual employee. For the year ended December 31, 2022, Dr. Valliant was eligible to receive an annual target cash bonus equal to 50% of his base salary, based on company performance. Dr. Burak and Mr. Crowley were eligible to receive an annual target cash bonus equal to 40% of their respective salaries, based on company and individual performance.

All final bonus payments to our named executive officers (other than for Dr. Valliant) are approved by our compensation committee. Any final bonus payment to Dr. Valliant is recommended by our compensation committee and approved by our board of directors. The actual bonuses, if any, awarded in a given year may vary from target, depending on individual performance and the achievement of corporate objectives and may also vary based on other factors at the discretion of our compensation committee (or board of directors, in the case of Dr. Valliant’s bonus).

For 2022, the corporate performance objectives generally fell into the following five categories: (1) advancing our FPI-1434 clinical program; (2) advancing our pipeline by progressing our FPI-1966 clinical program and our FPI-2059 program; (3) delivering on our partnerships, particularly our existing collaboration with AstraZeneca plc; (4) strengthening and leveraging our platform; and (5) strengthening our culture. In evaluating management’s performance relative to corporate performance for 2021, our compensation committee determined to award a corporate achievement level of 85% to executives (other than Dr. Valliant). This corporate achievement level along with each individual’s performance (other than Dr. Valliant) was then used to determine each named executive officer’s bonus. Our board of directors determined to award a corporate achievement level of 80% to Dr. Valliant. For 2022, we awarded bonuses to Dr. Valliant, Dr. Burak and, Mr. Crowley in the amounts of $309,824 CAD ($238,119 USD), $210,406 CAD ($161,710 USD) and $163,146, respectively.

Equity Compensation

Although we do not have a formal policy with respect to the grant of equity incentive awards to our named executive officers, we believe that equity grants provide our executives with a strong link to our long-term performance, create an ownership culture and help to align the interests of our executives and our shareholders. In addition, we believe that equity

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grants with a time-based vesting feature promote executive retention because this feature incentivizes our executive officers to remain in our employment during the vesting period. During the year ended December 31, 2022, we granted options to purchase common shares to each of our named executive officers, as described in more detail in the “Outstanding Equity Awards at 2022 Fiscal Year-End” table. In January 2023, as part of our annual compensation review, Dr. Valliant, Dr. Burak and Mr. Crowley were granted time-based stock options for 500,000 shares, 250,000 and 250,000 shares, respectively. These options vest in 48 equal monthly installments.

Employment Agreements with Our Named Executive Officers

We have entered into executive compensation arrangements, offer letters and an employment agreement, with each of our named executive officers. Except as noted below, these employment arrangements provide for “at will” employment.

John Valliant, Ph.D.—In June 2020 we entered into a new employment agreement with Dr. Valliant, replacing his existing employment agreement upon the completion of our initial public offering. The new employment agreement provides for Dr. Valliant’s continued employment and sets forth his 2020 annual base salary at $542,400, the terms of his discretionary annual bonus, certain expense reimbursements, his eligibility for accrued paid vacation, his obligation to cooperate with us in litigation and regulatory matters both during and after his employment, and his non-disparagement obligations both during and after his employment.

Pursuant to a Memorandum of Understanding (the “MOU”) between us, Dr. Valliant, and McMaster University (the “University”), dated July 1, 2018, Dr. Valliant will continue his employment with the University while also continuing in his appointment as our Chief Executive Officer. Pursuant to the terms of the MOU, Dr. Valliant remains on the University’s payroll and remains eligible for University benefits. In addition, we reimburse the University for 75% of the University’s payment of Dr. Valliant’s salary and benefits annually (including as Dr. Valliant’s base salary is increased) and correspondingly deduct such payments of base salary from us to Dr. Valliant. In the event Dr. Valliant’s services to us are terminated, we and Dr. Valliant will provide the University with not less than six weeks of advance written notice and we are responsible for reimbursing the University for 75% of the University’s payment of Dr. Valliant’s salary and benefits during such six-week notice period, including any associated costs, fees and expenses.

In addition, Dr. Valliant has entered into and is subject to our confidential information, assignment of inventions, and non-solicitation and non-competition agreements.

Eric Burak, Ph.D.—In June 2020 we entered into a new employment agreement with Dr. Burak, which replaced his existing employment agreement upon the completion of our initial public offering. The new employment agreement provides for Dr. Burak’s continued employment and sets forth his 2020 annual base salary at $413,500, the terms of his discretionary annual bonus, certain expense reimbursements, his eligibility for accrued paid vacation, his obligation to cooperate with us in litigation and regulatory matters both during and after his employment, and his non-disparagement obligations both during and after his employment.

In addition, Dr. Burak has entered into an agreement with us which contains protections of confidential information, requires assignment of inventions, restricts Dr. Burak from certain solicitation and competition activities during his employment and for a period thereafter.

John Crowley—In June 2020 we entered into a new employment agreement with Mr. Crowley, which replaced his existing employment agreement upon the completion of our initial public offering. The new employment agreement provides for Mr. Crowley’s continued employment and sets forth his 2020 annual base salary of $423,700, the terms of his discretionary annual bonus, certain expense reimbursements, his eligibility to participate in our benefit plans generally, his eligibility for accrued paid vacation, his obligation to cooperate with us in litigation and regulatory matters both during and after his employment, and his non-disparagement obligations both during and after his employment.

Benefits Provided Upon Termination Without Cause

Under the terms of the employment agreements we have entered into with each of Drs. Valliant and Burak and Mr. Crowley, if such executive’s employment is terminated by us without cause or by the executive for good reason (as defined in each executive’s employment agreement), subject to the executive’s signing a separation agreement that will include,

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among other things, a general release of potential claims against us, (1) he will be entitled to continue to receive his monthly base salary for a period of 12 months; (2) he will be entitled to any incentive compensation pursuant the employment agreement awarded in the year preceding the year of termination but not yet paid and a pro-rated annual bonus up to the date of termination (or, in the case of Dr. Valliant, his target annual bonus for the then-current year); (3) we will continue to make payments of group insurance benefits for Drs. Valliant and Burak for 12 months; and (4) for Mr. Crowley, subject to the respective copayment of employee premiums and respective proper election to receive benefits under the Consolidated Omnibus Budget Reconciliation Act of 1985, as amended (“COBRA”), the monthly employer contribution that we would have made to provide Mr. Crowley health insurance if either had remained employed by us until the earliest of (i) the 12 month anniversary of his date of termination, (ii) his eligibility for group medical plan benefits under any other employer group medical plan, or (iii) the cessation of his rights under COBRA.

Benefits Provided Upon a Change in Control

We have designed our change-in-control policies to provide income continuity after a change-in-control of the company that results in the executive being separated from the company. Our policy in the case of change-in-control benefits has been to structure these as “double trigger” benefits. In other words, the change-in-control does not itself trigger benefits; rather, benefits are paid only if the employment of the executive is terminated or the executive terminates his employment for good reason during a specified period after the change-in-control. We believe a “double trigger” benefit maximizes shareholder value because it prevents an unintended windfall to executives in the event of a friendly change-in-control, while still providing them appropriate incentives to cooperate in negotiating any change-in-control in which they believe they may lose their jobs. Under the terms of their respective employment arrangements, if, within one year following a change in control, each of our named executive officer’s employment is terminated by us or the succeeding company, as applicable, without cause or he terminates his employment for good reason (as defined in the applicable employment agreement), subject to the executive’s signing a separation agreement that will include a general release of potential claims against us:

In addition, Mr. Crowley has entered into an agreement with us which contains protections of confidential information, requires assignment of inventions, restricts him from certain solicitation activities during his employment and for a period thereafter, and restricts him from certain competitive activities during his employment and for a period thereafter. Pursuant to the agreement, Mr. Crowley is eligible to receive 50% of his respective highest annualized base salary paid by us within the

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two-year period preceding the last day of his employment during the post-employment non-competition period (but for not more than 12 months following the end of his employment) if we enforce the respective non-competition covenant, or garden leave pay. If Mr. Crowley is eligible to receive either any other severance or change in control payments as described above, such payment(s) shall be reduced by the amount of the garden leave pay.

Other Benefits and Perquisites

We offer participation in broad-based retirement, health and welfare plans to all of our colleagues, including our named executive officers. All of our full-time colleagues, including our named executive officers, are eligible to participate in a standard suite of health and welfare benefit plans, including those set forth below.

401(k) Plan

We maintain a tax-qualified retirement plan that provides eligible U.S. employees with an opportunity to save for retirement on a tax-advantaged basis. Plan participants are able to defer eligible compensation subject to applicable annual Internal Revenue Code limits. We provide a matching contribution of 100 percent of employee contributions up to 3.5% percent of compensation, which vests after two years of service. The 401(k) plan is intended to be qualified under Section 401(a) of the Internal Revenue Code with the 401(k) plan’s related trust intended to be tax exempt under Section 501(a) of the Internal Revenue Code. As a tax-qualified retirement plan, contributions to the 401(k) plan and earnings on those contributions are not taxable to the employees until distributed from the 401(k) plan.

RRSP

We maintain a Canadian registered retirement savings plan (the “RRSP”) that provides eligible Canadian employees with an opportunity to save for retirement on a tax-advantaged basis. We provide a matching contribution of 100 percent of employee contributions up to 3 percent of compensation.

Other

We also provide all employees, including executive officers, with a flexible spending account plan, health savings account, the right to purchase common shares under an employee share purchase plan and paid time off benefits, including vacation, sick time and holidays. We do not offer or provide any additional perquisites (other than those noted here) to the chief executive officer or any other executive officer of the company.

Compensation Risk Assessment

We believe that although a portion of the compensation provided to our executive officers and other employees is performance-based, our executive compensation program does not encourage excessive or unnecessary risk-taking. This is primarily due to the fact that our compensation programs are designed to encourage our executive officers and other employees to remain focused on both short-term and long-term strategic goals, in particular in connection with our pay-for-performance compensation philosophy. As a result, we do not believe that our compensation programs are reasonably likely to have a material adverse effect on the company.

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Outstanding Equity Awards at 2022 Fiscal Year-End

The following table summarizes the number of common shares that were underlying outstanding equity incentive plan awards for each named executive officer as of December 31, 2022.

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Other Compensation Agreements and Policies

Other Agreements

We have also entered into non-competition, non-solicitation and non-disclosure agreements with each of our named executive officers. Under the non-competition, non-solicitation and non-disclosure agreements, each named executive officer has agreed (i) not to compete with us during his employment and for a period of one year after the termination of his employment, (ii) not to solicit our employees during his employment and for a period of one year after the termination of his employment, (iii) to protect our confidential and proprietary information, and (iv) to assign to us related intellectual property developed during the course of his employment.

Insider Trading Policy Prohibitions and Hedging Policy

Our company maintains an Insider Trading Policy that prohibits our officers, directors, employees and designated consultants and contractors who in the course of the performance of their duties have access to material, nonpublic information regarding the Company from engaging in the following transactions:

Executive Officers

The following table lists the positions, names and ages of our executive officers as of April 27, 2023:

John Valliant, Ph.D. is a continuing member of our board of directors. See “Directors” above for more information about Dr. Valliant.

Dmitri Bobilev, M.D., age 56, has served as Chief Medical Officer since November 2022. Dr. Bobilev was most recently Vice President, Head of Clinical Development at Checkmate Pharmaceuticals, Inc. until Checkmates’ acquisition by Regeneron in May 2022. Prior to Checkmate, Dr. Bobilev was Vice President, Head of Clinical Development at Vedanta Biosciences from June 2018 to August 2020. He previously held clinical development leadership roles with Tesaro and Sanofi. Dr. Bobilev spent more than 10 years as a practicing medical and radiation oncologist. Dr. Bobilev received an M.D. from Omsk State Medical Academy.

Eric Burak, Ph.D., age 58, has served as our Chief Technology Officer since November 2021. Prior to that Dr. Burak served as our Chief Scientific Officer from February 2017 to October 2021. From October 2012 to February 2017, Dr. Burak served as the Chief Scientific Officer at CPDC. Prior to that, from June 2011 to October 2012, Dr. Burak served as Vice President, Development at Theracos, Inc., a pharmaceutical research and development company. Dr. Burak holds a Ph.D. in Analytical Chemistry from Temple University and a BS in Chemistry from Drexel University.

John Crowley, CPA, age 49, has served as our Chief Financial Officer since February 2019. From November 2016 to January 2019, Mr. Crowley served as Executive Vice President and Chief Financial Officer at Merus, Inc., a clinical-stage immuno-oncology company. From September 2013 to November 2016, Mr. Crowley served as the Corporate Senior Vice

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President, Corporate Controller and Chief Accounting Officer at Charles River Laboratories, Inc., a contract research organization. Mr. Crowley is a Certified Public Accountant and received a BS from Babson College in both Economics and Accountancy.

Christopher Leamon, Ph.D., age 57, has served as our Chief Scientific Officer since November 2021. Prior to joining Fusion, Dr. Leamon served as Executive Director, Radioligand Drug Discovery at Novartis AG, a pharmaceutical company, from December 2018 to October 2021 following the acquisition of Endocyte, Inc., a biopharmaceutical company, by Novartis. Dr. Leamon also served as Vice President, Discovery Research at Advanced Accelerator Applications, a subsidiary acquired by Novartis, from December 2018 to December 2020. At Endocyte, Dr. Leamon served as Vice President of Research from April 2000 to December 2018 and as Director of Biology and Biochemistry from February 1999 to April 2000. Prior to joining Endocyte, Dr. Leamon held various research and development roles at Ionis Pharmaceuticals, a biomedical pharmaceutical company, and GlaxoSmithKline, a healthcare company. Dr. Leamon holds a B.S. in chemistry from Baldwin Wallace University and a Ph.D. in biochemistry from Purdue University.

Mohit Rawat, age 43, has served as our President and Chief Business Officer since September 2021. Prior to joining Fusion, Mr. Rawat served in various positions at Novartis Oncology, a subsidiary of Novartis AG, a pharmaceutical company, from April 2015 to September 2021, most recently as Vice President, Global Disease Lead CML franchise. Prior to Novartis, Mr. Rawat served as Chief of Staff at Shire Pharmaceuticals, a pharmaceutical company, from June 2014 to October 2014. Prior to that, Mr. Rawat serves as Senior Director, Asset Team Lead, Senior Director Immunology and Neuroscience at Abbvie Pharmaceuticals, a pharmaceutical company, from August 2013 to May 2014. Mr. Rawat was an Engagement Manager at McKinsey & Company from July 2009 to August 2013. Mr. Rawat holds an M.B.A. from Harvard Business School, and M.S. in chemical engineering from Massachusetts Institute of Technology, a certificate in finance from the Sloane School of Management at Massachusetts Institute of Technology and M. Tech and B. Tech degrees in chemical engineering from Indian Institute of Technology.

There are no family relationships between or among any of our executive officers.

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Equity Compensation Plan Information

The following table contains information about our equity compensation plans as of December 31, 2022. In addition, from time to time, we may grant “inducement grants” pursuant to Nasdaq Listing Rule 5635(c)(4).

Equity Compensation Plan Information

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AUDIT COMMITTEE REPORT

Report of the Audit Committee of the Board of Directors

This report is submitted by the audit committee of the board of directors (the “board”). The audit committee currently consists of the three directors whose names appear below. None of the members of the audit committee is an officer or employee of the Company, and the board has determined that each member of the audit committee is “independent” for audit committee purposes as that term is defined under Rule 10A-3 of the Exchange Act, and the applicable rules of the Nasdaq Stock Market LLC (“Nasdaq”). Each member of the audit committee meets the requirements for financial literacy under the applicable rules and regulations of the SEC and Nasdaq. The board has designated Steve Gannon as an “audit committee financial expert,” as defined under the applicable rules of the SEC. The audit committee operates under a written charter adopted by the board.

The audit committee’s general role is to assist the board in monitoring our financial reporting process and related matters. Its specific responsibilities are set forth in its charter.

The audit committee has reviewed the Company’s financial statements for the fiscal year ended December 31, 2022, and met with management, as well as with representatives of PricewaterhouseCoopers LLP, the Company’s independent registered public accounting firm, to discuss the consolidated financial statements. The audit committee also discussed with members of PricewaterhouseCoopers LLP the matters required to be discussed by the Auditing Standard No. 1301, “Communication with Audit Committees,” as adopted by the Public Company Accounting Oversight Board.

In addition, the audit committee received the written disclosures and the letter from PricewaterhouseCoopers LLP required by applicable requirements of the Public Company Accounting Oversight Board and the SEC regarding the independent accountant’s communications with the audit committee concerning independence, and has discussed with members of PricewaterhouseCoopers LLP its independence.

Based on these discussions, the financial statement review and other matters it deemed relevant, the audit committee recommended to the board that the Company’s audited consolidated financial statements for the fiscal year ended December 31, 2022, be included in its 2022 Annual Report.

The information contained in this audit committee report shall not be deemed to be “soliciting material,” “filed” or incorporated by reference into any past or future filing under the Securities Exchange Act of 1934 or the Securities Act of 1933 unless and only to the extent that the Company specifically incorporates it by reference.

By the audit committee of the board of directors,

Steve Gannon, Chair

Chau Khuong

Heather Preston, M.D.

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PROPOSAL 2

APPOINTMENT OF OUR INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

In August 2019, we engaged PricewaterhouseCoopers LLP to serve as our independent registered public accounting firm. Our engagement partner rotates every five years, with the next rotation expected after the completion of our 2023 audit. Our board of directors recommend the re- appointment of PricewaterhouseCoopers LLP as auditors of Fusion to hold office until the termination of the next annual meeting of shareholders. Representatives of PricewaterhouseCoopers LLP are expected to be present at the Annual Meeting and will have the opportunity to make a statement, if they desire to do so, and will be available to respond to appropriate questions from our shareholders.

Principal Accounting Fees and Services

PricewaterhouseCoopers LLP audited our financial statements for the year ended December 31, 2022. Our shareholders are being asked to confirm at the annual meeting the appointment of PricewaterhouseCoopers LLP to serve as our independent registered public accounting firm for the fiscal year ending December 31, 2023.

The following table summarizes the fees of PricewaterhouseCoopers LLP billed or expected to be billed to us for each of the last two fiscal years.

All such accountant services and fees were pre-approved by our audit committee in accordance with the “Audit Committee Pre-Approval Policies and Procedures” described below.

Audit Committee Pre-Approval Policies and Procedures

Our audit committee has adopted procedures requiring the pre-approval of all audit and non-audit (including tax) services that are to be performed by our independent registered public accounting firm in order to assure that these services do not impair the auditor’s independence. These procedures generally approve the performance of specific services subject to a cost limit for all such services. This general approval is to be reviewed, and if necessary modified, at least annually. Management must obtain the specific prior approval of the audit committee for each engagement of our independent registered public accounting firm to perform any other audit or non-audit services. The audit committee does not delegate its responsibility to approve services performed by our independent registered public accounting firm to any member of management.

The standard applied by the audit committee in determining whether to grant approval of any type of non-audit service, or of any specific engagement to perform a non-audit service, is whether the services to be performed, the compensation to be paid therefor and other related factors are consistent with the independent registered public accounting firm’s independence

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under guidelines of the SEC and applicable professional standards. Relevant considerations include whether the work product is likely to be subject to, or implicated in, audit procedures during the audit of our financial statements, whether the independent registered public accounting firm would be functioning in the role of management or in an advocacy role, whether the independent registered public accounting firm’s performance of the service would enhance our ability to manage or control risk or improve audit quality, whether such performance would increase efficiency because of the independent registered public accounting firm’s familiarity with our business, personnel, culture, systems, risk profile and other factors, and whether the amount of fees involved, or the non-audit services portion of the total fees payable to the independent registered public accounting firm in the period would tend to reduce the independent registered public accounting firm’s ability to exercise independent judgment in performing the audit.

All of the services rendered by PricewaterhouseCoopers LLP with respect to the 2022 and 2021 fiscal years were pre-approved by the audit committee in accordance with this policy.

Vote Required

The appointment of PricewaterhouseCoopers LLP requires the affirmative vote of a majority of the common shares present in person or by proxy at the Annual Meeting and entitled to vote thereon. Abstentions will have the effect of a vote AGAINST this proposal.

OUR BOARD OF DIRECTORS UNANIMOUSLY RECOMMENDS THAT THE SHAREHOLDERS VOTE “FOR” THE APPOINTMENT OF PRICEWATERHOUSECOOPERS LLP AS OUR INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM FOR THE FISCAL YEAR ENDING DECEMBER 31, 2023.

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OTHER INFORMATION

Other Matters

Our board of directors does not know of any other matters which may come before the meeting. However, if any other matters are properly presented to the meeting, it is the intention of the persons named in the proxy card to vote, or otherwise act, in accordance with their judgment on such matters.

Section 16(a) Beneficial Ownership Reporting Compliance

Section 16(a) of the Exchange Act requires our directors and officers and holders of more than 10% of our common shares to file with the SEC, initial reports of ownership of our common shares and other equity securities on a Form 3 and reports of changes in such ownership on a Form 4 or Form 5. Directors and officers and holders of 10% of our common shares are required by SEC regulations to furnish us with copies of all Section 16(a) forms they file. The SEC has designated specific deadlines for these reports, and we must identify in this Proxy Statement those persons who did not file these reports when due. To our knowledge, based solely on a review of copies of such forms furnished to us, and written representations made by our directors and officers regarding their filing obligations, we believe all Section 16(a) filing requirements were satisfied on a timely basis with respect to the year ended December 31, 2022, except that forms for all of our independent director annual grants were not timely filed.

Shareholder Proposals for the 2024 Annual Meeting

A shareholder who is entitled to vote at the annual meeting of shareholders to be held in 2024 (the “2024 Annual Meeting”) may raise a proposal for consideration at the 2024 Annual Meeting. We will consider such proposal for inclusion in our proxy statement and form of proxy relating to our 2024 Annual Meeting only if:

In addition, in the event the Company does not receive a shareholder proposal by January 29, 2024, the proxy to be solicited by the board for the 2024 Annual Meeting will confer discretionary authority on the holders of the proxy to vote the Common Shares if the proposal is presented at the 2024 Annual Meeting without any discussion of the proposal in the proxy materials for that meeting.

To comply with the universal proxy rules (once effective), shareholders who intend to solicit proxies in support of director nominees other than the Company’s nominees must provide notice that sets forth the information required by Rule 14a-19 under the Exchange Act no later than April 15, 2024.

In addition, our by-laws establish an advance notice procedure for nominations for election to our board of directors and other matters that shareholders wish to present for action at an annual meeting other than those to be included in our proxy statement. In general, notice must be received at our principal executive offices not less than 30 calendar days before the annual meeting of shareholders. However, if the date of the annual meeting is less than 50 days after the date on which disclosure is first made in a press release reported by a national news service in Canada, or in a document publicly filed by the Company under its profile on the SEDAR at www.sedar.com, notice must be received not later than the close of business 10 calendar following such date. If the shareholder fails to give notice by these dates, then the persons named as proxies in the proxies solicited by the board of directors for the 2024 Annual Meeting may exercise discretionary voting power regarding any such proposal. Shareholders are advised to review our by-laws which also specify requirements as to the form and content of a shareholder’s notice.

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Shareholders also have the right under our by-laws to nominate director candidates directly, without any action or recommendation on the part of the nominating and corporate governance committee or the board of directors, by following the procedures set forth in our by-laws, including advance notice requirements. Candidates nominated by shareholders in accordance with the procedures set forth in our by-laws will not be included in our proxy card for the next annual meeting.

Any proposals, notices or information about proposed director candidates should be sent to:

Where You Can Find More Information

The Company files reports, proxy statements, and other information with the SEC, which is all publicly available on the SEC’s website, http://www.sec.gov, and with the Canadian securities administrators, which is all publicly available on SEDAR, www.sedar.com. Financial information is provided in the Company’s comparative annual financial statements and management’s discussion and analysis for the year ended December 31, 2022 in the Company’s annal filing on Form 10-K. You may also find any document we file with the SEC or Canadian securities regulators (and more) on our website at http://www.fusionpharma.com under the “Investors & Media” menu. References to our website are inactive textual references only and the contents of our website should not be deemed to be incorporated by reference into this proxy statement.

You should rely on the information contained in this document to vote your shares at the Annual Meeting. The Company has not authorized anyone to provide you with information that is different from what is contained in this document. This document is dated April 27, 2023. You should not assume that the information contained in this document or incorporated by reference in this document is accurate as of any later date, and the mailing of this document to shareholders at any time after that date does not suggest otherwise. This proxy statement does not constitute a solicitation of a proxy in any jurisdiction where, or to or from any person to whom, it is unlawful to make such proxy solicitations.

Important Notice Regarding Delivery of Shareholder Documents

Intermediaries are permitted to adopt a procedure called “householding,” which has been approved by the SEC. Under this procedure, you intermediary may deliver a single notice and, if applicable, the proxy materials, will be delivered to multiple shareholders who share the same address, unless contrary instructions have been received. Once you have received notice from your intermediary that they will be “householding” communications to your address, “householding” will continue until you are notifies otherwise or until you revoke your consent. If you prefer to receive separate multiple copies of the proxy materials at the same address you can request additional copies by contacting your broker or contacting us at our principal executive offices, Fusion Pharmaceuticals, Inc., 270 Longwood Road South, Hamilton, Ontario, Canada L8P 0A6, (289) 799-0891, Attn: Investor Relations, telephone (289) 799-0891. The Company will deliver those documents to such shareholder promptly upon receiving the request. Any such shareholder may also contact our Investor Relations department using the above contact information if he or she would like to receive separate proxy statements, notice of internet availability and annual reports in the future. If you are receiving multiple copies of our annual reports, notice of internet availability and proxy statements, you may request householding in the future by contacting our Investor Relations department.

Other Business

The board of directors knows of no business to be brought before the Annual Meeting which is not referred to in the accompanying Notice of Annual Meeting. Should any such matters be presented, the persons named in the proxy shall have the authority to take such action in regard to such matters as in their judgment seems advisable. If you hold shares through a broker, bank, or other nominee as described above, they will not be able to vote your shares on any other business that comes before the Annual Meeting unless they receive instructions from you with respect to such matter.

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YOUR VOTE IS IMPORTANT! PLEASE VOTE BY: P.O. BOX 8016, CARY, NC 27512-9903 INTERNET Go To: www.proxypush.com/FUSN Cast your vote online Have your Proxy Card ready Follow the simple instructions to record your vote PHONE Call 1-866-834-5856 Use any touch-tone telephone Have your Proxy Card ready Follow the simple recorded instructions MAIL Mark, sign and date your Proxy Card Fold and return your Proxy Card in the postage-paid envelope provided You must register to attend the meeting online and/or participate at www.proxydocs.com/FUSN Fusion Pharmaceuticals Inc. Annual Meeting of Shareholders For Shareholders of record as of April 18, 2023 TIME: Wednesday, June 14, 2023 10:00 AM, Eastern Time PLACE: Annual Meeting to be held live via the Internet - please visit www.proxydocs.com/FUSN for more details. This proxy is being solicited on behalf of the Board of Directors The undersigned hereby appoints John Crowley, Maria Stahl and John Valliant, or (print the name of the person the undersigned is appointing if this person is someone other than the management nominees listed), and each or either of them, as the true and lawful attorneys of the undersigned, with full power of substitution and revocation, and authorizes them, and each of them, to vote all the shares of common stock of Fusion Pharmaceuticals Inc. which the undersigned is entitled to vote at said meeting and any adjournment or postponement thereof upon the matters specified and upon such other matters as may be properly brought before the meeting or any adjournment or postponement thereof, conferring authority upon such true and lawful attorneys to vote in their discretion on such other matters as may properly come before the meeting and revoking any proxy heretofore given. THE SHARES REPRESENTED BY THIS PROXY WILL BE VOTED AS DIRECTED OR, IF NO DIRECTION IS GIVEN, SHARES WILL BE VOTED IDENTICAL TO THE BOARD OF DIRECTORS RECOMMENDATION. This proxy, when properly executed, will be voted in the manner directed herein. The securities represented by this proxy will be voted for or withheld from voting in respect of each of the matters described herein in accordance with the instructions of the holder, on any ballot that may be called for and, if the holder has specified a choice with respect to any matter to be acted on, the securities will be voted accordingly. This proxy confers discretionary authority in respect of amendments or variations to matters identified in the notice of meeting or other matters that may properly come before the meeting or any adjournment or postponement thereof. You are encouraged to specify your choice by marking the appropriate box (SEE REVERSE SIDE) but you need not mark any box if you wish to vote in accordance with the Board of Directors’ recommendation. The listed management nominees cannot vote your shares unless you sign (on the reverse side) and return this card. If at the meeting more than nine individuals are nominated for election, an instruction to vote "Against" a nominee will be treated as an instruction to "Withhold" from voting for that nominee. Every holder has the right to appoint some other person or company of their choice, who need not be a holder, to attend and act on their behalf at the meeting or any adjournment or postponement thereof. If you wish to appoint a person or company other than the listed management nominees printed above please insert the name of your chosen proxyholder in the space provided above. PLEASE BE SURE TO SIGN AND DATE THIS PROXY CARD AND MARK ON THE REVERSE SIDE

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Fusion Pharmaceuticals Inc. Annual Meeting of Shareholders Please make your marks like this: THE BOARD OF DIRECTORS RECOMMENDS A VOTE: FOR ON PROPOSALS 1 AND 2 PROPOSAL YOUR VOTE BOARD OF DIRECTORS RECOMMENDS 1. To elect nine directors, each to serve until the next annual meeting of shareholders and until his or her respective successors is duly elected and qualified, or such director's earlier death, resignation or removal. FOR AGAINST FOR FOR FOR FOR FOR FOR FOR FOR FOR 1.01 Donald Bergstrom, M.D., Ph.D. 1.02 Pablo Cagnoni, M.D. 1.03 Johan Christenson, M.D., Ph.D. 1.04 Barbara Duncan 1.05 Steve Gannon 1.06 Chau Khuong 1.07 Philina Lee, Ph.D. 1.08 Heather Preston, M.D. 1.09 John Valliant, Ph.D. 2. To appoint PricewaterhouseCoopers LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2023. FOR WITHHOLD FOR 3. To transact any other business that may properly come before the Annual Meeting or any adjournment thereof. You must register to attend the meeting online and/or participate at www.proxydocs.com/FUSN Authorized Signatures - Must be completed for your instructions to be executed. Please sign exactly as your name(s) appears on your account. If held in joint tenancy, all persons should sign. Trustees, administrators, etc., should include title and authority. Corporations should provide the full name of corporation and the name and title of the authorized officer signing this proxy. Signature (and Title if applicable) Date Signature (if held jointly) Date