What changed in this filing

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Item 9A. Controls and Procedures

2024-03-13 compared with 2023-03-30 · 421 added, 330 removed, 626 unchanged (55% of the section changed)

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Our management, with the participation of our Chief Executive Officer and Chief Financial Officer (our principal executive officer and principal financial officer, respectively), evaluated the effectiveness of our disclosure controls and procedures as of December 31, 2023.

The term “disclosure controls and procedures,”

as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), means controls and other procedures of a company that are designed to ensure that information required to be disclosed by a company in the reports that it files or submits under the Exchange Act is recorded, processed, summarized and reported, within the time periods specified in the SEC’s rules and forms.

Disclosure controls and procedures include, without limitation, controls and procedures designed to ensure that information required to be disclosed by a company in the reports that it files or submits under the Exchange Act is accumulated and communicated to the company’s management, including its principal executive and principal financial officers, as appropriate to allow timely decisions regarding required disclosure.

The term “disclosure controls and procedures,” as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), means controls and other procedures of a company that are designed to ensure that information required to be disclosed by a company in the reports that it files or submits under the Exchange Act is recorded, processed, summarized and reported, within the time periods specified in the SEC’s rules and forms.

Management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving their objectives and management necessarily applies its judgment in evaluating the cost-benefit relationship of possible controls and procedures.

Based on the evaluation of our disclosure controls and procedures as of December 31, 2023, our Chief Executive Officer and Chief Financial Officer concluded that, as of such date, our disclosure controls and procedures were effective at the reasonable assurance level.

Management’s Annual Report on Internal Controls Over Financial Reporting

Our management is responsible for establishing and maintaining adequate internal control over financial reporting as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act.

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Projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

Under the supervision and with the participation of our management, including our principal executive officer and principal financial officer, we conducted an evaluation of the effectiveness of our internal control over financial reporting based on the Internal Control –

Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission.

Based on our evaluation under that framework, our management concluded that our internal control over financial reporting was effective as of December 31, 2023.

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Directors, Executive Officers and Corporate Governance.

Set forth below are the names of our directors, their ages, their offices, if any, their principal occupations or employment for at least the past five years, the length of their tenure as directors and the names of other public companies in which such persons hold or have held directorships during the past five years.

Additionally, information about the specific experience, qualifications, attributes or skills that led to our Board of Directors’

conclusion that each person listed below should serve as a director is set forth below:

Set forth below are the names of our directors as of March 8, 2024, their ages, their offices, if any, their principal occupations or employment for at least the past five years, the length of their tenure as directors and the names of other public companies in which such persons hold or have held directorships during the past five years.

Additionally, information about the specific experience, qualifications, attributes or skills that led to our Board of Directors’ conclusion that each person listed below should serve as a director is set forth below:

Position with the Company

Milind Deshpande, Ph.D.

Chairman of the Board of Directors

Scott Jackson

Ankit Mahadevia, M.D.

Chief Executive Officer, President and Director

Pottage, Jr., M.D.

Satyavrat Shukla

Chief Executive Officer, President and Director

Cynthia Smith

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Patrick Vink, M.D.

Lead Director

Our Board of Directors has reviewed the materiality of any relationship that each of our directors has with Spero Therapeutics, Inc., either directly or indirectly.

Based upon this review, our Board of Directors has determined that the following members of the Board of Directors are “independent directors”

as defined by The Nasdaq Stock Market:

Based upon this review, our Board of Directors has determined that the following members of the Board of Directors are “independent directors” as defined by The Nasdaq Stock Market:

Milind Deshpande, Ph.D., Scott Jackson, John C.

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Thomas, Kathleen Tregoning and Patrick Vink, M.D.

See “Item 13.

Certain Relationships and Related Transactions, and Director Independence.”

See “Item 13.

Certain Relationships and Related Transactions, and Director Independence.”

Milind Deshpande, Ph.D.

has served on our Board of Directors since January 2014 and currently serves as chairman of our Board of Directors.

has served on our Board of Directors since January 2014 and previously served as Chairman of our Board of Directors from January 2014 to August 2023.

Deshpande is the President and Chief Executive Officer at Nayan Therapeutics since February 2019, and previously served as President and Chief Executive Officer of Avilar Therapeutics from January 2020 to June 2021.

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We believe that Mr.

Jackson’s extensive executive leadership experience in the pharmaceutical industry and his experience as a member of the board of directors of other publicly traded biotechnology companies, as well as his broad life sciences industry knowledge qualifies him to serve on our Board of Directors.

Ankit Mahadevia, M.D.

has served as our Chief Executive Officer and President since March 2015 and has been a member of our Board of Directors since September 2013.

has been a member of our Board of Directors since September 2013 and currently serves as Chairman of our Board of Directors, a position he has held since August 2023.

Mahadevia formerly served as our Chief Executive Officer and President from March 2015 until August 2023.

He was formerly a Venture Partner in the life sciences group at Atlas Venture, located in Cambridge, Massachusetts.

In that capacity, he supported the formation of eight companies focused on novel drug discovery platforms and therapeutic products, including Nimbus Therapeutics, Arteaus Therapeutics (acquired by Lilly), and Translate Bio (Nasdaq:

He led three of these companies as acting CEO, including Synlogic (Nasdaq:

In that capacity, he supported the formation of eight companies focused on novel drug

discovery platforms and therapeutic products, including Nimbus Therapeutics, Arteaus Therapeutics (acquired by Lilly), and Translate Bio (Nasdaq:

He led three of these companies as acting chief executive officer, including Synlogic (Nasdaq:

Prior to joining Atlas Venture in 2008, Dr.

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and at Vanda Pharmaceuticals Inc.

Previously, he worked in the health

care groups of McKinsey & Company and Monitor Group.

Previously, he worked in the health care groups of McKinsey & Company and Monitor Group.

Mahadevia began his career in health care policy, with roles in the U.S.

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Pottage served as Medical Director of Vertex Pharmaceuticals (Nasdaq:

VRTX) (“Vertex”).

Pottage currently serves on the board of directors of Pardes Biosciences.

VRTX) (“Vertex”).

Pottage currently serves on the board of directors of Pardes Biosciences, Inc.

We believe that Dr.

Pottage’s extensive industry and executive experience, his broad experience within the biopharmaceutical sector and his knowledge of the life sciences industry qualifies him to serve on our Board of Directors.

Satyavrat Shukla has served as our Chief Executive Officer and President since August 2023 and has been a member of our Board of Directors since August 2023.

He previously served as our Chief Financial Officer and Treasurer from January 2021 to August 2023.

He has over 20 years of strategic and financial leadership experience.

He was most recently Chief Financial Officer at Ziopharm Oncology, Inc.

from July 2019 to December 2020, where he directed all of Ziopharm’s financial aspects, including financial planning, analysis and reporting, treasury and tax functions, capital strategy and investor relations.

Prior to Ziopharm, Mr.

Shukla was Vice President and Global Head of Corporate Finance for Vertex.

from July 2012 to July 2019, where he managed financial planning, analysis and budgeting, and led the annual long-range planning process encompassing Vertex’s entire portfolio and operations across more than 30 countries.

Previously, Mr.

Shukla was a Principal at Cornerstone Research, where he led teams providing consulting services for life science clients ranging from start-ups to multi-billion-dollar corporations.

Prior to Cornerstone, he worked for finance consulting firms LECG Corporation and Putnam, Hayes & Bartlett, Inc.

Shukla earned a B.A.

in Economics from Harvard University and an M.B.A.

in Finance and Strategy from Yale University.

He also holds the Chartered Financial Analyst designation.

Cynthia Smith has served on our Board of Directors since March 2019.

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We believe that Ms.

Smith’s extensive management experience in the healthcare industry and her experience as a member of the board of directors of other publicly traded biotechnology companies, as well as her broad life sciences industry knowledge, qualifies her to serve on our Board of Directors.

Thomas has served on our Board of Directors since July 2017.

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Prior to Orchard, Mr.

Thomas served as the President and Chief Operating Officer of AMAG Pharmaceuticals, Inc., a commercial-stage pharmaceutical company, which was a publicly traded company that was subsequently acquired by Covis Pharma, from April 2015 to April 2017, as AMAG’s Executive Vice President and Chief Operating Officer from May 2012 through April 2015 and as Executive Vice President, Chief Financial Officer and Treasurer from August 2011 through May 2012.

Prior to AMAG, he served as Senior Vice President, Chief Operating Officer and Chief Financial Officer for Molecular Biometrics, Inc., a commercial-stage medical diagnostics company, from October 2008 to July 2011.

Thomas served as the President and Chief Operating Officer of AMAG Pharmaceuticals, Inc., a commercial-stage pharmaceutical company, which was a publicly traded company that was subsequently acquired by Covis Pharmaceuticals, Inc., from April 2015 to April 2017, as AMAG’s Executive Vice President and Chief Operating Officer from May 2012 through April 2015 and as Executive Vice President, Chief Financial Officer and Treasurer from August 2011 through May 2012.

Prior to AMAG, he served as Senior Vice President, Chief Operating Officer and Chief Financial Officer for Molecular Biometrics, Inc., a commercial-stage medical diagnostics company,

from October 2008 to July 2011.

Prior to Molecular Biometrics, Mr.

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We believe that Mr.

Thomas’

extensive commercial and operational management experience at biopharmaceutical companies and with financial matters qualifies him to serve on our Board of Directors.

Thomas’ extensive commercial and operational management experience at biopharmaceutical companies and with financial matters qualifies him to serve on our Board of Directors.

Kathleen Tregoning has served on our Board of Directors since October 2021.

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Prior to joining Sanofi, Ms.

Tregoning spent more than a decade at Biogen Inc., a multinational biotechnology company, first as Vice President, Public Policy & Government Affairs, from

2006 to 2015, and then as Senior Vice President, Corporate Affairs, from December 2015 to February 2017.

Tregoning spent more than a decade at Biogen Inc., a multinational biotechnology company, first as Vice President, Public Policy & Government Affairs, from 2006 to 2015, and then as Senior Vice President, Corporate Affairs, from December 2015 to February 2017.

Previously, Ms.

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Patrick Vink, M.D.

has served on our Board of Directors since September 2015.

has served on our Board of Directors since September 2015 and currently serves as our Lead Director, a position he has held since August 2023.

Vink has been an advisor to the pharmaceutical industry since 2015 and board member of several companies.

Previously, Dr.

Vink was employed at Cubist Pharmaceuticals, Inc (“Cubist”).

Most recently, he served as Executive Vice-President and Chief Operating Officer, overseeing all worldwide commercial and technical operations as well as global alliance management and managing the company’s profit and loss.

Vink was employed at Cubist Pharmaceuticals, Inc.

He joined Cubist in 2012 as Senior Vice President and Head of all International Business Operations.

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Vice President International Business for Biogen, Inc.;

and Head of Worldwide Marketing, Cardiovascular and Thrombosis for Sanofi-Synthélabo SA.

Vink served as a member of the Executive Committee of the European Federation of Pharmaceutical Industries and Associations (EFPIA) between 2013 and 2015.

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Term of Office of Directors

Our amended and restated By-Laws provide that our business is to be managed by or under the direction of our Board of Directors.

Our Amended and Restated Bylaws provide that our business is to be managed by or under the direction of our Board of Directors.

Our Board of Directors is divided into three classes for purposes of election.

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Our Board of Directors currently consists of eight members, classified into three classes as follows:

Milind Deshpande, Ph.D., Ankit Mahadevia, M.D.

and Kathleen Tregoning constitute our Class III directors with a term ending at the 2023 annual meeting;

Cynthia Smith, John C.

Cynthia Smith, Scott Jackson and John C.

Pottage, Jr., M.D.

and Scott Jackson constitute our Class I directors with a term ending at the 2024 annual meeting;

Patrick Vink, M.D.

Thomas constitute our Class II directors with a term ending at the 2025 annual meeting.

constitute our Class I directors with a term ending at the 2024 annual meeting of stockholders;

Patrick Vink, M.D., Frank E.

Thomas and Satyavrat Shukla constitute our Class II directors with a term ending at the 2025 annual meeting of stockholders;

Milind Deshpande, Ph.D., Ankit Mahadevia, M.D.

and Kathleen Tregoning constitute our Class III directors with a term ending at the 2026 annual meeting of stockholders.

Committees of the Board of Directors and Meetings

Meeting Attendance.

During the fiscal year ended December 31, 2022, there were 11 meetings of our Board of Directors, and the various committees of the Board of Directors met a total of 15 times.

During the fiscal year ended December 31, 2023, there were five meetings of our Board of Directors, and the various committees of the Board of Directors met a total of 12 times.

No director attended fewer than 75% of the total number of meetings of the Board of Directors and of committees of the Board of Directors on which such director served during the fiscal year ended December 31, 2023.

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Audit Committee.

Our Audit Committee met four times during the fiscal year ended December 31, 2022.

This committee currently has four members, Frank E.

Thomas (Chairman), Scott Jackson, John C.

Pottage, Jr., M.D., and Patrick Vink, M.D.

Our Audit Committee’s role and responsibilities are set forth in the Audit Committee’s written charter and include the authority to retain and terminate the services of our independent registered public accounting firm.

Our Audit Committee met six times during the fiscal year ended December 31, 2023.

This committee currently has three members, Frank E.

Thomas (Chair), Scott Jackson and John C.

Pottage, Jr., M.D.

During the period of January 1, 2023 through September 15, 2023, our Audit Committee consisted of Mr.

Thomas (Chair), Mr.

Pottage, and Dr.

In addition, the Audit Committee reviews annual financial statements, considers matters relating to accounting policy and internal controls and reviews the scope of annual audits.

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The Board of Directors has determined that Mr.

Thomas is an “audit committee financial expert,”

as the SEC has defined that term in Item 407 of Regulation S-K.

Thomas is an “audit committee financial expert,” as the SEC has defined that term in Item 407 of Regulation S-K.

Please also see the report of the Audit Committee set forth elsewhere in this proxy statement.

A copy of the Audit Committee’s written charter is publicly available on our website at www.sperotherapeutics.com.

Compensation Committee.

Our Compensation Committee (formerly, our Human Capital Management Committee) met five times during the fiscal year ended December 31, 2022.

This committee currently has four members, Patrick Vink, M.D.

(Chairman), Milind Deshpande, Ph.D., Cynthia Smith and Kathleen Tregoning.

Our Compensation Committee’s role and responsibilities are set forth in the Compensation Committee’s written charter and include reviewing, approving and making recommendations regarding our compensation policies, practices and procedures to ensure that legal and fiduciary responsibilities of the Board of Directors are carried out and that such policies, practices and procedures contribute to our success.

Our Compensation Committee met four times during the fiscal year ended December 31, 2023.

This committee currently has three members, Cynthia Smith (Chair), Patrick Vink, M.D., and Kathleen Tregoning.

During the period of January 1, 2023 through September 15, 2023, our Compensation Committee consisted of Dr.

Vink (Chair), Dr.

Deshpande, Ms.

Smith, and Ms.

Our Compensation Committee also administers the Spero Therapeutics, Inc.

2017 Stock Incentive Plan, as amended (the “2017 Plan”), and our 2019 Inducement Equity Incentive Plan, as amended (the “2019 Inducement Plan”).

The Compensation Committee is responsible for the determination of the compensation of our chief executive officer and shall conduct its decision-making process with respect to that issue without the chief executive officer present.

All members of the Compensation Committee qualify as independent under the definition promulgated by The Nasdaq Stock Market

The Compensation Committee retains Meridian Compensation Partners, LLC (“Meridian”) as an independent advisor to the Compensation Committee to provide executive compensation consulting services.

Meridian did not provide any services to us other than executive compensation consulting services during the fiscal year ended December 31, 2023.

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Their responses affirm the independence of Meridian and the partners, consultants, and employees who service the Compensation Committee on executive compensation matters and governance issues.

A copy of the Compensation Committee’s written charter is publicly available on our website at www.sperotherapeutics.com.

Nominating and Corporate Governance Committee .

Our Nominating and Corporate Governance Committee (“Nominating Committee”) met three times during the fiscal year ended December 31, 2022 and has three members, Milind Deshpande, Ph.D.

(Chairman), Scott Jackson and Frank E.

Our Nominating and Corporate Governance Committee (“Nominating Committee”) met two times during the fiscal year ended December 31, 2023 and has three members, Patrick Vink, M.D.

(Chair), Milind Deshpande, Ph.D., and Scott Jackson.

During the period of January 1, 2023 through September 15, 2023, our Nominating Committee consisted of Dr.

Deshpande (Chair), Mr.

Our Board of Directors has determined that all members of the Nominating Committee qualify as independent under the definition promulgated by The Nasdaq Stock Market.

The Nominating Committee’s responsibilities are set forth in the Nominating Committee’s written charter and include:

• identifying and recommending candidates for membership on our Board of Directors;

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Generally, our Nominating Committee considers candidates recommended by stockholders as well as from other sources such as other directors or officers, third party search firms or other appropriate sources.

Once identified, the Nominating Committee will evaluate a candidate’s qualifications in accordance with the criteria set forth in our Corporate Governance Guidelines.

Our Nominating Committee has not adopted a formal diversity policy in connection with the consideration of director nominations or the selection of nominees.

However, the Nominating Committee will consider issues of diversity among its members in identifying and considering nominees for director, and strive where appropriate to achieve a diverse balance of backgrounds, perspectives, experience, age, gender, ethnicity and country of citizenship on the Board of Directors and its committees.

If a stockholder wishes to propose a candidate for consideration as a nominee for election to the Board of Directors, it must follow the procedures described in our amended and restated By-Laws and in “Stockholder Proposals and Nominations For Director”

at the end of this proxy statement.

If a stockholder wishes to propose a candidate for consideration as a nominee for election to the Board of Directors, it must follow the procedures described in our Amended and Restated Bylaws and in “Stockholder Proposals and Nominations For Director” at the end of this proxy statement.

Any such recommendation should be made in writing to the Nominating and Governance Committee, care of our Secretary at our principal office and should be accompanied by the following information concerning each recommending stockholder and the beneficial owner, if any, on whose behalf the nomination is made:

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• a description of all relationships between the proposed nominee and the recommending stockholder or any beneficial owner, including any agreements or understandings regarding the nomination;

additional disclosures relating to stockholder nominees for directors, including completed questionnaires and disclosures required by our amended and restated By-Laws.

• additional disclosures relating to stockholder nominees for directors, including completed questionnaires and disclosures required by our Amended and Restated Bylaws.

Development Committee .

Our Development Committee met one time during the fiscal year ended December 31, 2023 and has three members, John C.

Pottage, Jr., M.D.

(Chair), Milind Deshpande, Ph.D., and Ankit Mahadevia, M.D.

Our Development Committee provides additional Board of Directors oversight and engagement with respect to the ongoing development of our product candidates and our research and development programs.

Corporate Governance Guidelines.

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The guidelines provide that:

our Board of Directors’

principal responsibility is to oversee our management;

• our Board of Directors’ principal responsibility is to oversee our management;

• except as required by Nasdaq rules, a majority of the members of our Board of Directors must be independent directors;

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• our nominating and corporate governance committee will oversee periodic self-evaluations of the Board of Directors to determine whether it and its committees are functioning effectively.

We have no formal policy regarding diversity of our board members, but our Corporate Governance Guidelines provide that the background and qualifications of the members of our Board of Directors considered as a group should provide a significant breadth of experience, knowledge, and ability to assist our Board of Directors in fulfilling its responsibilities.

Our priority in selection of board members is identification of members who will further the interests of our stockholders through their established records of professional accomplishment, the ability to contribute positively to the collaborative culture among our board members, knowledge of our business, understanding of the competitive landscape in which we operate and adherence to high ethical standards.

Copies of the Nominating Committee’s written charter and our Corporate Governance Guidelines are publicly available on our website at www.sperotherapeutics.com.

While we have no formal policy regarding diversity of our board members, our Corporate Governance Guidelines provide that the background and qualifications of the members of our Board of Directors considered as a group should provide a significant breadth of experience, knowledge, and ability to assist our Board of Directors in fulfilling its responsibilities.

Our priority in selection

of board members is the identification of members who will further the interests of our stockholders through their established records of professional accomplishment, the ability to contribute positively to the collaborative culture among our board members, knowledge of our business, understanding of the competitive landscape in which we operate and adherence to high ethical standards.

Copies of the Nominating Committee’s written charter and our Corporate Governance Guidelines are publicly available on our website at www.sperotherapeutics.com.

Code of Business Conduct and Ethics.

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None of our executive officers currently serves, or in the past fiscal year has served, as a member of our Board of Directors or Compensation Committee of any entity that has one or more executive officers serving on our Board of Directors or Compensation Committee.

For a description of transactions between us and members of our Compensation Committee and affiliates of such members, see “Certain Relationships and Related Person Transactions.”

Board Leadership Structure and Role in Risk Oversight

Our Board of Directors is currently chaired by Milind Deshpande, Ph.D.

As a general policy, our Board of Directors believes that separation of the positions of chairman and chief executive officer reinforces the independence of our Board of Directors from management, creates an environment that encourages objective oversight of management’s performance and enhances the

effectiveness of our Board of Directors as a whole.

Mahadevia serves as our Chief Executive Officer while Dr.

Deshpande serves as the chairman of our Board of Directors but is not an officer.

Our Board of Directors is currently chaired by Ankit Mahadevia, M.D.

As a general policy, our Board of Directors believes that separation of the positions of Chairman and Chief Executive Officer reinforces the independence of our Board of Directors from management, creates an environment that encourages objective oversight of management’s performance and enhances the effectiveness of our Board of Directors as a whole.

Shukla serves as our Chief Executive Officer, while Dr.

Mahadevia serves as the Chairman of our Board of Directors but is not an officer and Patrick Vink, M.D.

serves as Lead Director as he is an “independent” director.

Our Board of Directors oversees the management of risks inherent in the operation of our business and the implementation of our business strategies.

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In addition, our Board of Directors reviews the risks associated with our business strategies periodically throughout the year as part of its consideration of undertaking any such business strategies.

Each of our board committees also oversees the management of our risk that falls within the committee’s areas of responsibility.

In performing this function, each committee has full access to management, as well as the ability to engage advisors.

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Executive Officers

The following table sets forth certain information regarding our executive officers who are not also directors.

The following table sets forth certain information regarding our executive officers who are not also directors as of March 8, 2024.

We have employment agreements or consulting agreements with each of our executive officers.

Kamal Hamed, M.D.

Chief Medical Officer

Tamara Joseph

Chief Legal Officer

Timothy Keutzer

Chief Operating Officer

Satyavrat Shukla

Chief Financial Officer

Kamal Hamed has served as our Chief Medical Officer since September 2022.

Esther Rajavelu

Chief Financial Officer and Chief Business Officer

Kamal Hamed, M.D.

has served as our Chief Medical Officer since September 2022.

Hamed has over 20 years of experience leading various anti-infective clinical development programs in antibacterials, antivirals, antimalarials, and antifungals.

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degree from the University of South Florida.

Hamed completed a residency in Internal Medicine at UMDNJ–Robert Wood Johnson Medical School and a fellowship in Infectious Diseases at Stanford University School of Medicine.

He is a fellow of both the American College of Physicians and the Infectious Diseases Society of America and has published over 120 manuscripts in peer-reviewed journals.

Tamara Joseph has served as our Chief Legal Officer since December 2020.

She has over 20 years of leadership roles in the biotechnology sector, overseeing legal, public and government affairs, compliance and risk management.

Joseph most recently served as General Counsel at Millendo Therapeutics, Inc.

and previously served as General Counsel at Enzyvant Therapeutics Ltd., InVivo Therapeutics Holdings Corp., Cubist Pharmaceuticals, Inc., Mayne Pharma Ltd., and Transkaryotic Therapies, Inc.

Her experience also includes establishing and leading the international legal and public affairs departments of Biogen Idec Inc.

received her B.A.

in economics from Duke University, her J.D.

from the University of Michigan Law School and her L.L.M.

degrees from the College of Europe in Belgium and the University of Paris.

Timothy Keutzer has served as our Chief Operating Officer since February 2023 and previously served as our Chief Development Officer from June 2019 until February 2023 and as our Senior Vice President, Development from September 2015 to June 2019.

He has over 20 years’

experience in the pharmaceutical industry, spanning multiple functional and therapeutic areas.

He has over 20 years’ experience in the pharmaceutical industry, spanning multiple functional and therapeutic areas.

Prior to joining Spero, Mr.

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Keutzer was the program leader for ceftolozane/tazobactam, which progressed rapidly from Phase 1 to Phase 3, and was approved in the FDA in December of 2014.

Prior to that role, he also led several of Cubist’s inlicensed development programs, and also led the commercial supply chain for Cubicin.

His experience before Cubist spans multiple drug classes and includes preclinical PK/PD and clinical operations at Genetics Institute, as well as global strategic marketing and program management at Wyeth.

Tim began his career in contract toxicology labs.

Keutzer earned his bachelor’s degree from the University of Kentucky.

Satyavrat Shukla has served as our Chief Financial Officer since January 2021.

He has over 20 years of strategic and financial leadership experience.

He was most recently Chief Financial Officer at Ziopharm Oncology, Inc.

Prior to Ziopharm, Mr.

Shukla was Vice President and Global Head of Corporate Finance for Vertex Pharmaceuticals, Inc.

Previously, Mr.

Shukla was a Principal at Cornerstone Research, where he led teams providing consulting services for life science clients ranging from start-ups to multi-billion-dollar corporations.

Prior to Cornerstone, he worked for finance consulting firms LECG Corporation and Putnam, Hayes & Bartlett, Inc.

Shukla earned a B.A.

in Economics from Harvard University and an M.B.A.

in Finance and Strategy from Yale University.

He also holds the Chartered Financial Analyst designation.

Keutzer earned his bachelor’s degree from the University of Kentucky.

Esther Rajavelu has served as our Chief Financial Officer and Chief Business Officer since November 2023.

Rajavelu most recently served as Chief Financial Officer of Fulcrum Therapeutics, Inc.

(“Fulcrum”) from January 2022 to April 2023.

Prior to joining Fulcrum, Ms.

Rajavelu’s career in the biotechnology sector includes her time as an equities research analyst, investment banker, and strategy consultant.

She served as a senior equities research analyst at UBS Securities ("UBS”) from July 2020 to December 2021.

Prior to joining UBS, Ms.

Rajavelu served as a senior equities research analyst at Oppenheimer & Co.

("Oppenheimer”) from June 2018 to July 2020.

Prior to joining Oppenheimer, Ms.

Rajavelu served as an equities research analyst at Deutsche Bank from June 2014 to June 2018.

Prior to joining Deutsche Bank, she served as vice president, life sciences M&A and capital & debt advisory at Ernst & Young Capital Advisors, LLC ("EY Capital Advisors”) from 2011 to 2014.

Prior to joining EY Capital Advisors, she worked at Bank of America Merrill Lynch from 2006 to 2011 in the healthcare investment banking group where she focused on financing and strategic transactions in the biotechnology and medical devices sectors.

Rajavelu received a MBA from The Wharton School of the University of Pennsylvania and a B.A.

in Economics and International Relations from Wesleyan University

Director or Officer Involvement in Certain Legal Proceedings

Our directors and executive officers have not been involved in any legal proceedings as described in Item 401(f) of Regulation S-K in the past ten years.

Executiv e Compensation.

The following table shows the total compensation paid or accrued during the last two fiscal years ended December 31, 2022 and 2021 to our President and Chief Executive Officer and our two next most highly compensated executive officers who earned more than $100,000 during the fiscal year ended December 31, 2022 and were serving as executive officers as of such date.

Executive Compensation.

The following table shows the total compensation paid or accrued during the last two fiscal years ended December 31, 2023 and 2022 to our current President and Chief Executive Officer, our former President and Chief Executive Officer, and our two next most highly compensated executive officers who earned more than $100,000 during the fiscal year ended December 31, 2023 and were serving as executive officers as of such date (the “named executive officers”).

Name and Principal Position

Incentive Plan

Ankit Mahadevia, M.D.

Chief Executive Officer

Satyavrat Shukla

Chief Financial Officer

Chief Executive Officer and President

Ankit Mahadevia, M.D.

Former Chief Executive Officer and President (6)

Tamara Joseph

Chief Legal Officer

(1) Consists of retention bonuses paid to Dr.

Mahadevia, Mr.

Shukla and Ms.

Joseph during the year ended December 31, 2022 and a sign-on bonus to Mr.

Shukla in connection with his commencement of employment during the year ended December 31, 2021.

Former Chief Legal Officer (7)

Timothy Keutzer

Chief Operating Officer

Consists of retention bonuses paid to Mr.

Mahadevia, Ms.

Joseph and Mr.

Keutzer during the years ended December 31, 2023 and 2022.

These amounts represent the aggregate grant date fair value for RSU awards computed in accordance with ASC 718.

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The annual cash bonuses are paid in the first quarter of the calendar year following the year to which the cash bonus relates.

(5) Amounts in this column include for the year ended December 31, 2022 (i) in the case of Dr.

Mahadevia, $583 consists of the dollar value of life insurance premiums we paid with respect to term life insurance and $9,150 in a matching contribution under our 401(k) plan, (ii) in the case of Mr.

Shukla, $583 consists of the dollar value of life insurance premiums we paid with respect to term life insurance and $3,550 in a matching contribution under our 401(k) plan and (iii) in the case of Ms.

Joseph, $583 consists of the dollar value of life insurance premiums we paid with respect to term life insurance and $6,731 in a matching contribution under our 401(k) plan.

(6) Amounts in this column include for the year ended December 31, 2021 (i) in the case of Dr.

Mahadevia, $740 consists of the dollar value of life insurance premiums we paid with respect to term life insurance and $5,505 in a matching contribution under our 401(k) plan, (ii) in the case of Mr.

Shukla, $740 consists of the dollar value of life insurance premiums we paid with respect to term life insurance and $7,555 in a matching contribution under our 401(k) plan and (iii) in the case of Ms.

Joseph, $740 consists of the dollar value of life insurance premiums we paid with respect to term life insurance and $5,259 in a matching contribution under our 401(k) plan.

Amounts in this column include for the year ended December 31, 2023 (i) in the case of Mr.

Shukla, $583 consists of the dollar value of life insurance premiums we paid with respect to term life insurance and $9,900 in a matching contribution under our 401(k) plan, (ii) in the case of Dr.

Mahadevia, $340 consists of the dollar value of life insurance premiums we paid with respect to term life insurance, and $9,419 in a matching contribution under our 401(k) plan, $225,719 consists of the pro-rata bonus for calendar year 2023, paid pursuant to the Mahadevia Separation Agreement (as defined below), $11,509 consists of COBRA payments pursuant to the Mahadevia Separation Agreement, $197,250 consists of compensation earned during the year ended December 31, 2023 pursuant to the Mahadevia Consulting Agreement (as defined below), and $31,250 consists of cash compensation earned for his services as a member of our board of directors during the year ended December 31, 2023, and $23,200 consists of RSUs granted for service on our board of directors, each as further described below under “Director Compensation,” (iii) in the case of Ms.

Joseph, $583 consists of the dollar value of life insurance premiums we paid with respect to term life insurance and $6,874 in a matching contribution under our 401(k) plan and (iv) in the case of Mr.

Keutzer, $583 consists of the dollar value of life insurance premiums we paid with respect to term life insurance and $9,900 in a matching contribution under our 401(k) plan.

Mahadevia served as our Chief Executive Officer and President until August 2023.

Thereafter, Dr.

Mahadevia continued to serve as a member of the Board and serves as a consultant to the Company.

Joseph’s employment as our Chief Legal Officer ended effective March 6, 2024.

Narrative Disclosure to Summary Compensation Table

Our employment arrangements with our named executive officers are described below.

Our employment and consulting arrangements with the named executive officers are described below.

Satyavrat Shukla

On December 9, 2020, we entered into an employment agreement with Mr.

Shukla with respect to his employment as our Chief Financial Officer, as amended on November 10, 2022.

The terms of Mr.

Shukla’s agreement provided for an annual base salary of $425,000 prorated for fiscal year 2021, and eligibility for an annual incentive bonus, with a target bonus opportunity of 40% of his

then-current base salary, subject to adjustment by the Board of Directors or Compensation Committee.

Shukla’s annual base salary has been subsequently increased over time.

As of July 1, 2021, Mr.

Shukla's base salary was increased to $460,000, with a target bonus opportunity of 40% of his base salary.

In December 2021, Mr.

Shukla’s base salary was increased, effective February 1, 2022, to $480,000 with a target bonus opportunity of 40% of his base salary.

In January 2023, Mr.

Shukla’s base salary was increased, effective February 1, 2023, to $489,600 with a target bonus opportunity of 40% of his base salary.

On June 13, 2023, we entered into an Amended and Restated Employment Agreement with Mr.

Shukla with connection with his appointment as our Chief Executive Officer and President (the “Shukla Amended Employment Agreement”).

Under the terms of the Shukla Amended Employment Agreement, (i) the Company shall pay Mr.

Shukla an annual base salary (the “Base Salary”) of $575,000;

Shukla shall be eligible to receive an annual cash bonus (the “Annual Performance Bonus”), with the target amount of such Annual Performance Bonus equal to 50% of Mr.

Shukla’s Base Salary in the year to which the Annual Performance Bonus relates;

provided that the actual amount of the Annual Performance Bonus may be greater or less than such target amount;

provided further that Mr.

Shukla’s Annual Performance Bonus for the 2023 performance year shall be pro-rated such that it shall be based on a Base Salary of $489,600 for the period from January 1, 2023 to July 31, 2023 and on a Base Salary of $575,000 for the period from the Transition Date to December 31, 2023;

and (iii) the Company awarded Mr.

Shukla 266,000 restricted stock units (the “Shukla RSUs”) under the Plan on the Transition Date;

the Shukla RSUs are subject to the terms and conditions of the Plan and the restricted stock unit agreement between Mr.

Shukla and Company entered into pursuant thereto (the “Shukla RSU Agreement”);

and the Shukla RSUs shall vest in four equal annual installments beginning on the first anniversary of the Transition Date, except as otherwise provided in the Shukla RSU Agreement.

In January 2024, Mr.

Shukla’s base salary was increased, effective January 1, 2024, to $603,750 with a target bonus opportunity remaining at 50% of his base salary.

The Shukla Amended Employment Agreement also provides for the following severance payments upon termination by the Company without Cause (as defined in the Shukla Amended Employment Agreement) or by Mr.

Shukla for Good Reason (as defined in the Shukla Amended Employment Agreement):

(i) payment of his then-current Base Salary for a period of 12 months following termination;

(ii) a pro-rated target bonus for the period during which Mr.

Shukla was employed in the year of termination;

and (iii) continued coverage under the Company’s group health insurance plan until the earlier of 12 months from termination or the date Mr.

Shukla becomes eligible for medical benefits with another employer.

Further, the Shukla Amended Employment Agreement provides that upon termination by the Company without Cause or by Mr.

Shukla for Good Reason within (i) 90 days prior to the earlier to occur of a Change of Control (as defined in the Shukla Amended Employment Agreement) or the execution of a definitive agreement, the consummation of which would result in a Change of Control or (ii) one year following a Change of Control, Mr.

Shukla will be entitled to receive:

(i) a lump sum payment equal to 18 months of his then-current Base Salary plus an amount equal to one-and-one-half times the target amount of his Annual Performance Bonus;

(ii) acceleration of all unvested equity awards as of the date of termination;

and (iii) continued coverage under the Company’s group health insurance plan until the earlier of 18 months from termination or the date Mr.

Shukla becomes eligible for medical benefits with another employer.

Payment in each case is subject to Mr.

Shukla’s execution of a release satisfactory to the Company following such termination.

In addition, if Mr.

Shukla’s employment terminates as a result of disability or death, he will be entitled to receive a pro-rated target bonus for the period during which he was employed in the year of termination.

Ankit Mahadevia, M.D.

On October 20, 2017, we entered into an employment agreement with Dr.

Mahadeiva with respect to his employment as our Chief Executive Officer, as amended on November 10, 2022.

Mahadevia with respect to his employment as our Chief Executive Officer, as amended on November 10, 2022.

The terms of Dr.

Mahadeiva’s agreement provide for an annual base salary of $400,000, and eligibility for an annual incentive bonus, with a target bonus opportunity of 30% of his then-current base salary, subject to adjustment by the Board of Directors or Compensation Committee.

Mahadeiva’s annual base salary and target bonus opportunity have been subsequently increased over time.

In December 2020, Dr.

Mahadevia’s base salary was increased, effective February 1, 2021, to $565,000, with a target bonus opportunity of 50% of his base salary.

As of July 1, 2021, Dr.

Mahadevia’s base salary was increased to $620,000, with a target bonus opportunity of 60% of his base salary.

Mahadevia’s agreement provided for an annual base salary of $400,000, and eligibility for an annual incentive bonus, with a target bonus opportunity of 30% of his then-current base salary, subject to adjustment by the Board of Directors or Compensation Committee.

Mahadevia’s annual base salary and target bonus opportunity were subsequently increased over time.

In December 2021, Dr.

Mahadevia’s base salary was increased, effective February 1, 2022, to $635,000, with a target bonus opportunity of 60% of his base salary.

In January 2023, Dr.

Mahadevia’s base salary was increased, effective February 1, 2023, to $647,700, with a target bonus opportunity of 60% of his base salary.

This agreement provides for the following increased severance payments upon termination by us without Cause (as defined below) or by Dr.

Mahadevia’s base salary was increased, effective February 1, 2023, to $647,700, with a target bonus opportunity of 60% of his base salary.

Mahadevia stepped down as Chief Executive Officer effective August 1, 2023.

On June 13, 2023, we entered into a (i) Transition and Separation Agreement with Dr.

Mahadevia (the “Mahadevia Separation Agreement”) and (ii) Consulting Agreement with Dr.

Mahadevia (the “Mahadevia Consulting Agreement”), each as described below.

Mahadevia’s employment agreement provided for the following increased severance payments upon termination by us without Cause (as defined below) or by Dr.

Mahadevia for Good Reason (as defined below):

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Mahadevia becomes eligible for medical benefits with another employer.

Further, the agreement provides that upon termination by us without Cause or by Dr.

Mahadevia for Good Reason within 90 days prior to the earlier to occur of a Change of Control (as defined below) or the execution of a definitive agreement the consummation of which would result in a Change of Control or one year following a Change of Control (a “Change of Control Termination”), Dr.

Mahadevia will be entitled to receive (i) a lump sum payment equal to 18 months of his then-current base salary plus the amount of his then-current target performance bonus;

Further, the agreement provided that upon termination by us without Cause or by Dr.

Mahadevia was entitled to

receive (i) a lump sum payment equal to 18 months of his then-current base salary plus the amount of his then-current target performance bonus;

(ii) acceleration of all unvested equity awards as of the date of termination;

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Mahadevia becomes eligible for medical benefits with another employer.

Payment in each case is subject to Dr.

Mahadevia’s execution of a release satisfactory to us following such termination.

Payment in each case was subject to Dr.

Mahadevia’s execution of a release satisfactory to us following such termination.

In addition, if Dr.

Mahadevia’s employment terminates as a result of disability or death, he shall be entitled to receive a pro-rated target bonus for the period during which Dr.

Mahadevia’s employment terminated as a result of disability or death, he was entitled to receive a pro-rated target bonus for the period during which Dr.

Mahadevia was employed in the year of termination.

The agreement also provides that Dr.

The agreement also provided that Dr.

Mahadevia shall serve as a member of our Board of Directors during his employment with us until the term of his directorship expires and he is not re-elected or his earlier resignation or removal from our Board of Directors.

Satyavrat Shukla

On December 9, 2020, we entered into an employment agreement with Mr.

Shukla with respect to his employment as our Chief Financial Officer, as amended on November 10, 2022.

The terms of Mr.

Shukla’s agreement provide for an annual base salary of $425,000 prorated for fiscal year 2021, and eligibility for an annual incentive bonus, with a target bonus opportunity of 40% of his then-current base salary, subject to adjustment by the Board of Directors or Compensation Committee.

Shukla’s annual base salary has been subsequently increased over time.

As of July 1, 2021, Mr.

Shukla's base salary was increased to $460,000, with a target bonus opportunity of 40% of his base salary.

In December 2021, Mr.

Shukla’s base salary was increased, effective February 1, 2022, to $480,000 with a target bonus opportunity of 40% of his base salary.

In January 2023, Mr.

Shukla’s base salary was increased, effective February 1, 2023, to $489,600 with a target bonus opportunity of 40% of his base salary.

The agreement also provides for the following severance payments upon termination by us without Cause or by Mr.

Shukla for Good Reason:

(i) payment of his then-current base salary for a period of nine months following termination;

(ii) a pro-rated target bonus for the period during which Mr.

Shukla was employed in the year of termination;

and (iii) continued coverage under our group health insurance plan until the earlier of 12 months from termination or the date Mr.

Shukla becomes eligible for medical benefits with another employer.

Further, the agreement provides that upon termination by us without Cause or by Mr.

Shukla for Good Reason within 90 days prior to the earlier to occur of a Change of Control or a Change of Control Termination, Mr.

Shukla will be entitled to receive:

(i) a lump sum payment equal to 12 months of his then-current base salary plus the amount of his then-current target performance bonus;

(ii) acceleration of all unvested equity awards as of the date of termination;

and (iii) continued coverage under our group health insurance plan until the earlier of 12 months from termination or the date Mr.

Shukla becomes eligible for medical benefits with another employer.

Payment in each case is subject to Mr.

Shukla’s execution of a release satisfactory to us following such termination.

In addition, if Mr.

Shukla’s employment terminates as a result of disability or death, he shall be entitled to receive a pro-rated target bonus for the period during which Mr.

Shukla was employed in the year of termination.

On June 13, 2023, we entered into the Mahadevia Separation Agreement.

Pursuant to the terms of the Mahadevia Separation Agreement, (i) Dr.

Mahadevia remained eligible to receive a bonus amount representing a pro-rata bonus for calendar year 2023, subject to the discretion of the Board, calculated through August 1, 2023 (the “Transition Date”), which was paid within ten days following the Transition Date;

Mahadevia is eligible for and elects to continue his health insurance coverage under the Consolidated Omnibus Budget Reconciliation Act (“COBRA”) following the Transition Date, then the Company shall pay his monthly premium under COBRA until the earliest of (A) January 31, 2024;

(B) the expiration of his continuation coverage under COBRA;

or (C) the date when he becomes eligible to receive health insurance coverage in connection with new employment or self-employment;

(iii) that the Company enter into the Mahadevia Consulting Agreement;

(iv) notwithstanding any terms of the Company’s 2017 Plan, or any award agreements to the contrary, in the event of a Change of Control (as defined in the Mahadevia Consulting Agreement) and provided Dr.

Mahadevia is a member of the Board on the effective date of the Change of Control, Dr.

Mahadevia shall become fully vested in any and all equity awards outstanding as of the effective date of the Change of Control;

Mahadevia was appointed by the Board of Directors to serve as Chairman of the Board, effective as of the Transition Date.

On June 13, 2023, we entered into the Mahadevia Consulting Agreement.

Pursuant to the terms of the Mahadevia Consulting Agreement, Dr.

Mahadevia will perform certain consulting services for the Company which commenced on the Transition Date and continues through July 31, 2025, including advising the Company on general operational and strategic matters (the “Mahadevia Services”).

Under the Mahadevia Consulting Agreement, the Company shall pay Dr.

Mahadevia (i) $54,000 per month for the Mahadevia Services from the Transition Date through January 31, 2024 and (ii) an hourly rate of $310.00 per hour beginning on February 1, 2024 and continuing through July 31, 2025.

Further, the equity that Dr.

Mahadevia received under the 2017 Plan and any Stock Option Agreement or Restricted Stock Unit Agreement executed pursuant thereto prior to the Transition Date (collectively, the “Mahadevia Award Agreements”) shall continue to vest in accordance with the terms of the Plan and the Mahadevia Award Agreements during the term of the Mahadevia Consulting Agreement.

Mahadevia may exercise any vested options during the term of the Mahadevia Consulting Agreement and for 90 days following a termination event triggering an exercise period applicable to same (but no later than the date such award expires) in accordance with the terms of the Plan and the applicable Mahadevia Award Agreements.

In addition, in the event of a Change of Control (as defined in Mahadevia Consulting Agreement) on or before July 31, 2025, Dr.

Mahadevia shall become fully vested in any and all equity awards outstanding as of the effective date of such Change of Control, provided that the Mahadevia Consulting Agreement remains in effect as of the effective date of such Change of Control.

Tamara Joseph

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The terms of Ms.

Joseph’s agreement provide for an annual base salary of $385,000 prorated for fiscal year 2020, and eligibility for an annual incentive bonus, with a target bonus opportunity of 40% of her then-current base salary, subject to adjustment by the Board of Directors or Compensation Committee.

Joseph’s annual base salary has been subsequently increased over time.

Joseph’s agreement provided for an annual base salary of $385,000 prorated for fiscal year 2020, and eligibility for an annual incentive bonus, with a target bonus opportunity of 40% of her then-current base salary, subject to adjustment by the Board of Directors or Compensation Committee.

Joseph’s annual base salary has been subsequently increased over time.

As of July 1, 2021, Ms.

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In December 2021, Ms.

Joseph’s base salary was increased, effective February 1, 2022, to $450,000 with a target bonus opportunity of 40% of her base salary.

In January 2023, Ms.

Joseph’s base salary was increased, effective February 1, 2023, to $459,000 with a target bonus opportunity of 40% of her base salary.

In January 2024, Ms.

Joseph’s base salary was increased, effective January 1, 2024, to $475,065 with a target bonus opportunity of 40% of her base salary.

The agreement also provides for the following severance payments upon termination by us without Cause or by Ms.

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Payment in each case is subject to Ms.

Joseph’s execution of a release satisfactory to us following such termination.

Joseph’s execution of a release satisfactory to us following

such termination.

In addition, if Ms.

Joseph’s employment terminates as a result of disability or death, she shall be entitled to receive a pro-rated target bonus for the period during which Ms.

Joseph was employed in the year of termination.

Under each of the employment agreements, Cause means (i) the executive’s conviction of (A) a felony or (B) any misdemeanor involving moral turpitude, deceit, dishonesty or fraud;

(ii) the executive’s willful failure or refusal to comply with lawful directions of our Board of Directors (or, for Mr.

Shukla and Ms.

Joseph, the lawful directions of Dr.

Mahadevia), which failure or refusal continues for more than thirty days after written notice is given to the executive by our Board of Directors (or, for Mr.

Shukla and Ms.

Joseph, by Dr.

Mahadevia), which notice sets forth in reasonable detail the nature of such failure or refusal;

(iii) willful and material breach by the executive of a written company policy applicable to the executive or the executive’s covenants and/or obligations under his or her employment agreement or the material breach of the executive’s proprietary information and inventions assignment agreement;

Effective as of March 6, 2024, Ms.

Joseph’s employment as our Chief Legal Officer ended.

In connection with Ms.

Joseph stepping down, she is entitled to receive severance pay in the amount of $356,298.75, payable as continued salary in accordance with the our regular payroll dates and a pro rated cash bonus equal to $34,266.98 for the year ending December 31, 2024, which will be paid to Ms.

Joseph when we pay the 2024 annual bonuses to our employees in 2025, but in any event no later than March 15, 2025.

To implement the foregoing, we and Ms.

Joseph entered into a Separation Agreement.

We also entered into the Joseph Consulting Agreement, effective as of March 6, 2024, pursuant to which Ms.

Joseph will provide consulting services to us on an hourly, as needed basis, for a term of nine months following March 6, 2024 at a rate of $395.00 per hour.

Joseph’s employee stock options and RSUs will continue to vest during the term of the Joseph Consulting Agreement and after the term of the Joseph Consulting Agreement ends, all of Ms.

Joseph’s then vested and unexercised options and RSUs will be exercisable for 90 days in accordance with the terms of such options and RSUs and the 2017 Plan and the 2019 Inducement Plan, as applicable.

Timothy Keutzer

On January 1, 2020, we entered into an employment agreement with Mr.

Keutzer with respect to his employment as our Chief Development Officer, as amended on November 10, 2022.

The terms of Mr.

Keutzer’s agreement provided for an annual base salary of $ 330,000 and eligibility for an annual incentive bonus, with a target bonus opportunity of 40% of his then-current base salary, subject to adjustment by the Board of Directors or Compensation Committee.

Keutzer’s annual base salary has been subsequently increased over time.

In December 2021, Mr.

Keutzer’s base salary was increased, effective February 1, 2022, to $425,000 with a target bonus opportunity of 40% of his base salary.

On February 1, 2023, we entered into an Amended and Restated Employment Agreement with Mr.

Keutzer with connection with his appointment as our Chief Operating Officer (the “Keutzer Amended Employment Agreement”).

Under the terms of the Keutzer Amended Employment Agreement, the Company shall pay Mr.

Keutzer an annual base salary of $459,000, with a target bonus opportunity of 40% of his base salary.

In January 2024, Mr.

Keutzer’s base salary was increased, effective January 1, 2024, to $475,065 with a target bonus opportunity remaining at 40% of his base salary.

The agreement also provides for the following severance payments upon termination by us without Cause or by Mr.

Keutzer for Good Reason:

(i) payment of his then-current base salary for a period of nine months following termination;

(ii) a pro-rated target bonus for the period during which Mr.

Keutzer was employed in the year of termination;

and (iii) continued coverage under our group health insurance plan until the earlier of 12 months from termination or the date Mr.

Keutzer becomes eligible for medical benefits with another employer.

Further, the agreement provides that upon termination by us without Cause or by Mr.

Keutzer for Good Reason within 90 days prior to the earlier to occur of a Change of Control or a Change of Control Termination, Mr.

Keutzer will be entitled to receive:

(i) a lump sum payment equal to 12 months of his then-current base salary plus the amount of his then-current target performance bonus;

(ii) acceleration of all unvested equity awards as of the date of termination;

and (iii) continued coverage under our group health insurance plan until the earlier of 12 months from termination or the date Mr.

Keutzer becomes eligible for medical benefits with another employer.

Payment in each case is subject to Mr.

Keutzer ‘s execution of a release satisfactory to us following such termination.

In addition, if Mr.

Keutzer’s employment terminates as a result of disability or death, he shall be entitled to receive a pro-rated target bonus for the period during which Mr.

Keutzer was employed in the year of termination.

Under each of the employment agreements, Cause means (i) the executive’s conviction of (A) a felony or (B) any misdemeanor involving moral turpitude, deceit, dishonesty or fraud;

(ii) the executive’s willful failure or refusal to comply with lawful directions of our Board of Directors (or, for Mr.

Keutzer and Ms.

Joseph, the lawful directions of the Chief Executive Officer), which failure or refusal continues for more than thirty days after written notice is given to the executive by our Board of Directors (or, for Mr.

Keutzer and Ms.

Joseph, by the Chief Executive Officer), which notice sets forth in reasonable detail the nature of such failure or refusal;

and/or (iv) material misconduct by the executive that seriously discredits or damages us or any of our affiliates.

Under each of the employment agreements, Good Reason means (i) relocation of the executive’s principal business location to a location more than thirty (30) miles from the executive’s then-current business location;

(ii) a material diminution in the executive’s duties, authority or responsibilities;

(iii) a material reduction in the executive’s base salary;

(iv) willful and material breach by us of our covenants and/or obligations under the executive’s employment agreement;

or (v) within one year following a Change of Control, the executive is not an executive of the parent company, provided that the executive’s roles responsibilities and scope of authority within the subsidiary is not comparable to the executive’s roles, responsibilities and scope of authority with us prior to the Change of Control.

Under each of the employment agreements, Change of Control means (i) any person (as such term is used in Sections 13(d) and 14(d) of the Exchange Act) becomes the beneficial owner, directly or indirectly, of securities of the Company representing fifty percent (50%) or more of the total voting power represented by the Company’s then outstanding voting securities (excluding for this purpose any such voting securities held by the Company, or any affiliate, parent or subsidiary of the Company, or by any employee benefit plan of the Company) pursuant to a transaction or a series of related transactions;

(ii) a merger or consolidation of the Company other than a merger or consolidation which would result in the voting securities of the Company outstanding immediately

prior thereto continuing to represent (either by remaining outstanding or by being converted into voting securities of the surviving entity or the parent of such corporation) at least fifty percent (50%) of the total voting power represented by the voting securities of the Company or such surviving entity or parent of such corporation, as the case may be, outstanding immediately after such merger or consolidation;

(ii) a material diminution in the executive’s duties, authority or responsibilities;

(iii) a material reduction in the executive’s base salary;

(iv) willful and material breach by us of our covenants and/or obligations under the executive’s employment agreement;

(ii) a merger or consolidation of the Company other than a merger or consolidation which would result in the voting securities of the Company outstanding immediately prior thereto continuing to represent (either by remaining outstanding or by being converted into voting securities of the surviving entity or the parent of such corporation) at least fifty percent (50%) of the total voting power represented by the voting securities of the Company or such surviving entity or parent of such corporation, as the case may be, outstanding immediately after such merger or consolidation;

(iii) our stockholders approve an agreement for the sale or disposition by the Company of all or substantially all of our assets;

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Outstanding Equity Awards at 2023 Fiscal Year-End

The following table shows grants of stock options and awards outstanding on the last day of the fiscal year ended December 31, 2022 to each of the executive officers named in the Summary Compensation Table.

The following table shows grants of stock options and awards outstanding on the last day of the fiscal year ended December 31, 2023 to each of the named executive officers.

Option Awards

Unexercisable

Ankit Mahadevia, M.D.

Satyavrat Shukla

Ankit Mahadevia, M.D.

Tamara Joseph

Timothy Keutzer

The market value of the stock awards is based on the closing price of our common stock of $1.47 per share on December 29, 2023.

(2) 100% of these options vested on August 24, 2019.

(3) These options vested on April 28, 2020.

(4) 100% of these options vested on July 6, 2017.

(5) 100% of these options vested on July 6, 2021.

(6) 100% of these options vested on December 13, 2021.

25% of the options vested on January 4, 2022 and an additional 1/36th of the remaining shares vest monthly until the option is fully vested.

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In addition, in the event of a Change of Control Termination, the vesting of these options will accelerate in accordance with the terms of the option and his or her employment agreement.

(9) 25% of the options vested on February 1, 2022 and an additional 1/36th of the remaining shares vest monthly until the option is fully vested.

In addition, in the event of a Change of Control Termination, the vesting of these options will accelerate in accordance with the terms of the option and his or her employment agreement.

(10) 25% of the options vested on February 1, 2023 and an additional 1/36th of the remaining shares vest monthly until the option is fully vested.

In addition, in the event of a Change of Control Termination, the vesting of these options will accelerate in accordance with the terms of the option and his or her employment agreement.

Consists of RSUs.

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The RSUs vest in four equal annual installments beginning on February 1, 2023, subject to the individual's continued service through the applicable vesting date.

Consists of RSUs.

Each RSU represents the right to receive one share of common stock upon vesting.

The RSUs vest in four equal annual installments beginning on February 1, 2024, subject to the individual's continued service through the applicable vesting date.

Consists of RSUs.

Each RSU represents the right to receive one share of common stock upon vesting.

The RSUs vest in four equal annual installments beginning on August 1, 2024 subject to the individual's continued service through the applicable vesting date.

100% of these options vested on August 24, 2019.

100% of these options vested on April 28, 2020.

100% of these options vested on July 6, 2017.

100% of these options vested on July 6, 2021.

100% of these options vested on December 13, 2021.

100% of these options vested on January 2, 2023.

25% of the options vested on February 3, 2021 and an additional 1/36th of the remaining shares vest monthly until the option is fully vested.

In addition, in the event of a Change of Control Termination, the vesting of these options will accelerate in accordance with the terms of the option and his or her employment agreement.

25% of the options vested on February 1, 2022 and an additional 1/36th of the remaining shares vest monthly until the option is fully vested.

In addition, in the event of a Change of Control Termination, the vesting of these options will accelerate in accordance with the terms of the option and his or her employment agreement.

25% of the options vested on December 2, 2021 and an additional 1/36th of the remaining shares vest monthly until the option is fully vested.

In addition, in the event of a Change of Control Termination, the vesting of these options will accelerate in accordance with the terms of the option and his or her employment agreement.

During the year ended December 31, 2022, the executive officers named in the Summary Compensation Table did not exercise any stock options.

During the year ended December 31, 2023, the named executive officers did not exercise any stock options.

2022 Retention Cash Bonus and Performance Awards

On July 1, 2022, upon recommendation of the Compensation Committee, the Board of Directors approved a cash and RSU retention award for the Company’s executive officers, including awards to Dr.

Mahadevia, M.D., Mr.

Shukla and Ms.

Joseph consisting of the following:

Subject to Dr.

Mahadevia remaining actively employed with us through May 31, 2023, Dr.

Mahadevia will receive:

(i) a cash bonus of $254,000, which was paid on November 30, 2022 and (ii) if certain performance criteria are achieved, a number of shares of common stock to be issued to him on May 31, 2023 having a value of $508,000 based on the common stock price at such time, subject to the discretion of the Board or the Compensation Committee to pay in cash or a combination of cash and stock.

Subject to Mr.

Shukla remaining actively employed with us through May 31, 2023, Mr.

Shukla shall receive:

(i) a cash bonus of $168,000, which was paid on November 30, 2022 and (ii) if certain performance criteria are achieved, a number of shares of common stock to be issued to him on May 31, 2023 having a value of $336,000 based on the common stock price at such time, subject to the discretion of the Board or the Compensation Committee to pay in cash or a combination of cash and stock.

Subject to Ms.

Joseph remaining actively employed with us through May 31, 2023, Ms.

Joseph shall receive:

(i) a cash bonus of $157,500, which was paid on November 30, 2022 and (ii) if certain performance criteria are achieved, a number of shares of common stock to be issued to her on May 31, 2023 having a value of $315,000 based on the common stock price at such time, subject to the discretion of the Board or the Compensation Committee to pay in cash or a combination of cash and stock.

The RSUs are eligible for vesting based on the achievement of certain performance criteria by May 31, 2023 relating to pipeline execution, business development, and financial stewardship.

RSUs for which the performance criteria have not been achieved as specified by May 31, 2023 will lapse and be forfeited.

The RSUs will be subject to acceleration of vesting in the event of termination of employment without cause by us or by the executive for good reason (each as defined in the executive’s employment agreement).

On July 1, 2022, upon recommendation of the Compensation Committee, the Board of Directors approved a cash and RSU retention award for the Company’s executive officers, including awards to Mr.

Mahadevia, Ms.

Joseph and Mr.

Keutzer consisting of the following:

Shukla received:

(i) a cash bonus of $168,000, which was paid on November 30, 2022, and (ii) upon the achievement of certain performance criteria as of May 31, 2023, a cash payment of $336,000, which was paid in June 2023.

Mahadevia received:

(i) a cash bonus of $254,000, which was paid on November 30, 2022, and (ii) upon the achievement of certain performance criteria as of May 31, 2023, a cash payment of $508,000, which was paid in June 2023.

Joseph received:

(i) a cash bonus of $157,500, which was paid on November 30, 2022, and (ii) upon the achievement of certain performance criteria as of May 31, 2023, a cash payment of $315,000, which was paid in June 2023.

Keutzer received:

(i) a cash bonus of $148,785, which was paid on November 30, 2022, and (ii) upon the achievement of certain performance criteria as of May 31, 2023, a cash payment of $297,500, which was paid in June 2023.

The payments were based on the achievement of certain performance criteria by May 31, 2023 relating to pipeline execution, business development, and financial stewardship.

Potential Payments upon Termination or Change-In-Control

The employment agreements provide for the following severance payments upon termination by us without Cause or by the employee for Good Reason:

(i) payment of the employee’s then-current base salary for a period of nine months following termination (12 months in the case of the Chief Executive Officer);

(ii) a pro-rated target bonus for the period during which the employee was employed in the year of termination;

and (iii) continued coverage under our group health insurance plan until the earlier of 12 months from termination or the date the employee becomes eligible for medical benefits with another employer.

Further, the agreements provide that upon termination by us without Cause or by the employee for Good Reason within 90 days prior to or one year following the earlier to occur of a Change of Control (as defined in the executive’s employment agreements) or the execution of a definitive agreement the consummation of which would result in a Change of Control, the employee will be entitled to receive:

(i) a lump sum payment equal to 12 months of the employee’s then-current base salary plus a pro-rated target bonus for the period during which the employee was employed in the year of termination;

Payment in each case is subject to the employee’s execution of a release satisfactory to us following such termination.

In addition, if the employee’s employment terminates as a result of disability or death, he or she shall be entitled to receive a pro-rated target bonus for the period during which the employee was employed in the year of termination.

(i) a lump sum payment equal to 12 months of the employee’s then-current base salary plus a pro-rated target bonus for the period during which the employee was employed in the year of termination;

(ii) acceleration of unvested equity awards as of the date of termination in accordance with the terms of the executive’s employment agreement, as described above under “Narrative Disclosure to Summary Compensation Table;” and (iii) continued coverage under our group health insurance plan until the earlier of 12 months from termination or the date the employee becomes eligible for medical benefits with another employer.

Payment in each case is subject to the employee’s execution of a release satisfactory to us following such termination.

Director Compensation

7 unchanged sentences

Scott Jackson

Ankit Mahadevia, M.D.

Pottage, Jr., M.D.

6 unchanged sentences

A discussion of the assumptions used in determining grant date fair value may be found in Note 8 to our consolidated financial statements, included in this Annual Report on Form 10-K for the fiscal year ended December 31, 2023.

Mahadevia served as our President and Chief Executive Officer for part of 2023;

as such, his compensation earned as a director is disclosed in the Summary Compensation Table above.

Represents an option to purchase 30,942 shares of common stock at an exercise price of $1.74.

7 unchanged sentences

Scott Jackson

Ankit Mahadevia, M.D.

Pottage, Jr., M.D.

3 unchanged sentences

Non-Employee Director Compensation Policy

Under our Non-Employee Director Compensation Policy as amended (the “Non-Employee Director Compensation Policy”), each non-employee director is eligible to receive compensation for his or her service consisting of annual cash retainers and equity awards.

Under our Non-Employee Director Compensation Policy, as amended (the “Non-Employee Director Compensation Policy”), each non-employee director is eligible to receive compensation for his or her service consisting of annual cash retainers and equity awards.

Our non-employee directors received the following annual retainers for their service as of December 31, 2023:

4 unchanged sentences

Nominating and Governance Committee Chair

Development Committee Chair

Audit Committee Member

1 unchanged sentence

Nominating and Governance Committee Member

Development Committee Member

Our Non-Employee Director Compensation Policy provides the following with respect to equity awards to non-employee directors:

(i) the initial equity award consisting of a non-qualified stock option to purchase shares of our common stock upon first appointment to our Board of Directors and vesting in equal monthly installments until the third anniversary of the grant date subject to the non-employee director’s continued service in the amount of 15,000 shares, and (ii) annual equity awards consisting of a non-qualified stock option to purchase shares of our common stock vesting on the first anniversary of the grant date subject to the non-employee director’s continued service in the amount of 7,500 shares.

(i) the initial equity award consisting of a non-qualified stock option to purchase shares of our common stock upon first appointment to our Board of Directors and vesting in equal monthly installments until the third anniversary of the grant date subject to the non-employee director’s continued service in the amount of 15,000 shares, and (ii) annual equity awards consisting of a grant of 20,000 RSUs (each RSU relating to one share of our common stock) on the date of our annual meeting of stockholders.

The RSUs vest on the first anniversary of the grant date, subject to the director’s continued service, and are issued under, and are subject to the terms of, the 2017 Plan.

The policy also provides that, prior to the beginning of each calendar year, a non-employee director may elect to receive all or a portion of his or her base annual fee for service on our Board of Directors in the form of a non-qualified stock option to purchase a number of shares of our common stock based on the Black-Scholes value of such option, which option will be granted on the first business day of the calendar year.

These options vest in four quarterly installments on the last day of each calendar quarter during the calendar year, subject to the continued service of the non-employee director.

In July 2022, upon the recommendation of the Compensation Committee, the Board of Directors approved an RSU grant representing 15,000 shares of common stock to be issued to each director on the date of the 2022 annual meeting of stockholders in lieu of the annual equity award consisting of a stock option to purchase 7,500 shares of our common stock as described in the current Non-Employee Director Compensation Policy.

The RSUs will vest on the first anniversary of the grant date, subject to the director’s continued service, and were issued under, and are subject to the terms of, our 2017 Plan.

Directors may be reimbursed for travel, food, lodging and other expenses directly related to their service as directors.

Directors are also entitled to the protection provided by their indemnification agreements and the indemnification provisions in our amended and restated certificate of incorporation and amended and restated By-Laws.

Security Ownership of Certain Beneficial Own ers and Management and Related Stockholder Matters.

Directors are also entitled to the protection provided by their indemnification agreements and the indemnification provisions in our Amended and Restated Certificate of Incorporation, as amended, and Amended and Restated Bylaws.

Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters.

The following table sets forth certain information with respect to the beneficial ownership of our common stock as of March 8, 2024 for (a) the executive officers named in the Summary Compensation Table on Item 11 of this Amendment, (b) each of our directors and director nominees, (c) all of our current directors and executive officers as a group and (d) each stockholder known by us to own beneficially more than 5% of our common stock.

9 unchanged sentences

GSK Equity Investments, Limited (1)

Anson Funds Management, LP (2)

Named Executive Officers and Directors

Ankit Mahadevia, M.D.

Satyavrat Shukla (3)

Timothy Keutzer (4)

Tamara Joseph (5)

1 unchanged sentence

Scott Jackson (7)

Ankit Mahadevia, M.D.

Pottage, Jr., M.D.

8 unchanged sentences

This information is based solely on a Schedule 13D/A filed by GlaxoSmithKline plc with the SEC on January 20, 2023, which reported ownership as of November 14, 2022.

(2) Consists of (i) 65,817 shares of common stock held by Mahadevia-Mehta Family Trust, of which Dr.

Mahadevia is the trustee, and (ii) 40,811 shares of common stock and (iii) 1,086,273 shares of common stock underlying options that are exercisable as of March 1, 2023 or will become exercisable within 60 days after such date held by Dr.

Consists of shares of common stock owned by Anson Funds Management LP.

The address for Anson Funds Management LP is 16000 Dallas Parkway, Suite 800, Dallas, Texas 75248.

This information is based solely on a Schedule 13G filed by Anson Funds Management LP with the SEC on February 14, 2024, which reported ownership as of December 31, 2023.

Consists of 92,419 shares of common stock underlying options that are exercisable as of March 8, 2024 or will become exercisable within 60 days after such date held by Mr.

Consists of (i) 63,813 shares of common stock and (ii) 237,542 shares of common stock underlying options that are exercisable as of March 8, 2024 or will become exercisable within 60 days after such date held by Mr.

Consists of (i) 61,378 shares of common stock and (ii) 93,982 shares of common stock underlying options that are exercisable as of March 8, 2024 or will become exercisable within 60 days after such date held by Ms.

Joseph, our former Chief Legal Officer.

Consists of (i) 16,454 shares of common stock and (ii) 83,664 shares of common stock underlying options that are exercisable as of March 8, 2024 or will become exercisable within 60 days after such date held by Dr.

Consists of 30,000 shares of common stock underlying options that are exercisable as of March 8 , 2024 or will become exercisable within 60 days after such date held by Mr.

Consists of (i) 65,817 shares of common stock held by Mahadevia-Mehta Family Trust, of which Dr.

Mahadevia is the trustee, and (ii) 154,052 shares of common stock and (iii) 1,223,183 shares of common stock underlying options that are exercisable as of March 8, 2024 or will become exercisable within 60 days after such date held by Dr.

Consists of 33,219 shares of common stock underlying options that are exercisable as of March 8, 2024 or will become exercisable within 60 days after such date held by Dr.

3 unchanged sentences

Consists of 82,067 shares of common stock underlying options that are exercisable as of March 8, 2024 or will become exercisable within 60 days after such date held by Dr.

(12) See 2 through 11 above;

also includes shares of common stock underlying options that are exercisable as of March 1, 2023 or will become exercisable within 60 days after such date held by Mr.

Keutzer and Dr.

Hamed, who are executive officers but not named executive officers.

See 3 and 4 and 6 through 13 above;

also includes shares of common stock underlying options that are exercisable as of March 8, 2024 or will become exercisable within 60 days after such date held by Dr.

Hamed, who is an executive officer but not a named executive officer.

Equity Compensation Plan Information

8 unchanged sentences

options, warrants and

rights ($) (4)

Number of securities

8 unchanged sentences

This plan category consists of our 2017 Plan.

(2) This plan category consists of our 2019 Plan.

This plan category consists of our 2019 Inducement Plan.

Represents shares of common stock issuable upon the exercise of outstanding stock options and vesting of outstanding RSUs.

Represents the weighted-average exercise price of outstanding options to purchase shares of common stock issued under our plans.

Benefits Programs

Each named executive employee is eligible to participate in our benefits programs, which include health, life, disability and dental insurance and a 401(k) retirement savings plan.

Spero Therapeutics, Inc.’s 2017 Stock Incentive Plan

We adopted the Spero Therapeutics, Inc.

2017 Plan on June 28, 2017, as amended on October 18, 2017 and August 17, 2021 and September 15, 2022.

2017 Plan on June 28, 2017, as amended on October 18, 2017 and August 17, 2021, September 15, 2022 and October 5, 2023.

The 2017 Plan will expire on June 30, 2027.

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• provide that outstanding options will be assumed or substituted for options of the successor corporation;

provide that the outstanding options must be exercised within a certain number of days, either to the extent the options are then exercisable, or at our Board of Directors’

discretion, any such options being made partially or fully exercisable;

terminate outstanding options in exchange for a cash payment of an amount equal to the difference between (a) the consideration payable upon consummation of the corporate transaction to a holder of the number of shares into which such option would have been exercisable to the extent then exercisable, or in our Board of Directors’

discretion, any such options being made partially or fully exercisable, and (b) the aggregate exercise price of those options;

• provide that the outstanding options must be exercised within a certain number of days, either to the extent the options are then exercisable, or at our Board of Directors’ discretion, any such options being made partially or fully exercisable;

• terminate outstanding options in exchange for a cash payment of an amount equal to the difference between (a) the consideration payable upon consummation of the corporate transaction to a holder of the number of shares into which such option would have been exercisable to the extent then exercisable, or in our Board of Directors’ discretion, any such options being made partially or fully exercisable, and (b) the aggregate exercise price of those options;

• provide that outstanding stock grants will be substituted for shares of the successor corporation or consideration payable with respect to our outstanding stock in connection with the corporate transaction;

terminate outstanding stock grants in exchange for payment of an amount equal to the consideration payable upon consummation of the corporate transaction to a holder of the same number of shares comprising the stock grant, to the extent the stock grant is no longer subject to any forfeiture or repurchase rights, or at our Board of Directors’

discretion, all forfeiture and repurchase rights being waived upon the corporate transaction.

• terminate outstanding stock grants in exchange for payment of an amount equal to the consideration payable upon consummation of the corporate transaction to a holder of the same number of shares comprising the stock grant, to the extent the stock grant is no longer subject to any forfeiture or repurchase rights, or at our Board of Directors’ discretion, all forfeiture and repurchase rights being waived upon the corporate transaction.

For purposes of determining such payments, in the case of a corporate transaction the consideration for which, in whole or in part, is other than cash, the consideration other than cash shall be valued at the fair market value thereof as determined in good faith by our Board of Directors.

Spero Therapeutics, Inc.’s 2019 Inducement Equity Incentive Plan

On March 11, 2019, the Board of Directors adopted Spero Therapeutics, Inc.’s 2019 Plan, as amended on June 23, 2020 and December 22, 2022.

The Board of Directors initially reserved 331,500 shares of our common stock under the 2019 Inducement Plan to be used exclusively for grants of awards to individuals that were not previously our employees or directors, as an inducement to the individual’s entry into employment with us within the meaning of Rule 5635(c)(4) of the Nasdaq Listing Rules.

Spero Therapeutics, Inc.’s 2019 Inducement Equity Incentive Plan

On March 11, 2019, the Board of Directors adopted Spero Therapeutics, Inc.’s 2019 Inducement Plan, as amended on June 23, 2020, December 22, 2022, July 27, 2023, and October 30, 2023.

As previously disclosed, in June 2020, the Board of Directors approved an amendment to the 2019 Inducement Plan to increase the number of shares of common stock authorized for issuance thereunder by 700,000 shares.

In December 2022, the Board of Directors approved an amendment to the 2019 Inducement Plan to increase the number of shares of common stock authorized for issuance thereunder by 875,000 shares.

In July 2023, the Board of Directors approved an amendment to the 2019 Inducement Plan to increase the number of shares of common stock authorized for issuance thereunder by 250,000 shares.

In October 2023, the Board of Directors approved an amendment to the 2019 Inducement Plan to increase the number of shares of common stock authorized for issuance thereunder by 500,000 shares.

The 2019 Inducement Plan was adopted without stockholder approval pursuant to Rule 5635(c)(4).

9 unchanged sentences

The following is a description of transactions since January 1, 2022, to which we have been a party, in which the amount involved exceeds $120,000, and in which any of our directors, executive officers or holders of more than 5% of our capital stock, or an affiliate or immediate family member thereof, had or will have a direct or indirect material interest.

We refer to such transactions as “related party transactions”

and such persons as “related parties.”

With the approval of our Board of Directors, we have engaged in the related party transactions described below.

We refer to such transactions as “related party transactions” and such persons as “related parties.” With the approval of our Board of Directors, we have engaged in the related party transactions described below.

We believe the terms obtained or consideration that we paid or received, as applicable, in connection with the transactions described below were comparable to terms available or the amounts that would be paid or received, as applicable, from unaffiliated third parties.

2 unchanged sentences

On September 21, 2022, we entered into the GSK License Agreement with GSK.

Pursuant to the terms of the GSK License Agreement, we granted GSK an exclusive royalty-bearing license, with the right to grant sublicenses, under our intellectual property and regulatory documents and a sublicense under certain intellectual property of Meiji and Meiji’s regulatory documents to develop, manufacture and commercialize the GSK Licensed Products in the GSK Territory.

Under the terms of the GSK License Agreement, we received an upfront payment of $66.0 million for GSK to secure rights to the medicine and are eligible to receive up to $525.0 million in development, sales, and commercial milestones payments, as well as low single-digit to low double-digit tiered royalties on net product sales.

Royalties are subject to reduction in the event of third-party licenses, entry of a generic product or expiration of patent and regulatory exclusivity prior to the tenth anniversary of the first commercial sale of a GSK Licensed Product in a particular country.

The terms of the License Agreement are described further above under “Business - Collaboration, License and Service Agreements - Tebipenem HBr Agreements - GSK License Agreement.”

In July 2023, we entered into Amendment 1 to the GSK License Agreement, which updated the technology transfer terms of the GSK License Agreement.

In December 2023, we entered into Amendment 2 to the GSK License Agreement, which added a country to the locations for PIVOT-PO.

Under the terms of Amendment 2, we may receive up to an additional $4.3 million in tranched milestones based on activities in such country.

The terms of the License Agreement are described further above under “Business - Collaboration, License and Service Agreements - Tebipenem HBr Agreements - GSK License Agreement.”

Share Purchase Agreement

1 unchanged sentence

The GSK SPA contains certain standstill, lock-up and registration rights provisions.

Indemnification Agreements with Officers and Directors and Directors’

and Officers’

Liability Insurance

Indemnification Agreements with Officers and Directors and Directors’ and Officers’ Liability Insurance

We have entered into indemnification agreements with each of our executive officers and directors.

The indemnification agreements, our amended and restated certificate of incorporation and our amended and restated By-Laws require us to indemnify our directors to the fullest extent not prohibited by Delaware law.

Subject to certain limitations, our amended and restated certificate of incorporation also requires us to advance expenses incurred by our directors and officers, subject to limited exceptions.

The indemnification agreements, our Amended and Restated Certificate of Incorporation, as amended, and our Amended and Restated Bylaws require us to indemnify our directors to the fullest extent not prohibited by Delaware law.

Subject to certain limitations, our Amended and Restated Certificate of Incorporation, as amended, also requires us to advance expenses incurred by our directors and officers, subject to limited exceptions.

We also maintain a general liability insurance policy which covers certain liabilities of our directors and officers arising out of claims based on acts or omissions in their capacities as directors or officers.

2 unchanged sentences

Any request for such a transaction must first be presented to our Audit Committee for review, consideration and approval.

In approving or rejecting any such proposal, our Audit Committee is to consider the relevant facts and circumstances available and deemed relevant to the Audit Committee, including, but not limited to, the extent of the related party’s interest in the transaction, and whether the transaction is on terms no less favorable to us than terms we could have generally obtained from an unaffiliated third party under the same or similar circumstances.

transaction is on terms no less favorable to us than terms we could have generally obtained from an unaffiliated third party under the same or similar circumstances.

Director Independence

3 unchanged sentences

Thomas, Kathleen Tregoning and Patrick Vink, M.D.

would qualify as “independent”

as that term is defined by Nasdaq Listing Rule 5605(a)(2).

Ankit Mahadevia, M.D.

would not qualify as “independent”

under applicable Nasdaq Listing Rules applicable to the Board of Directors generally or to separately designated Board committees because he currently serves as our Chief Executive Officer.

would qualify as “independent” as that term is defined by Nasdaq Listing Rule 5605(a)(2).

Satyavrat Shukla would not qualify as “independent” under applicable Nasdaq Listing Rules applicable to the Board of Directors generally or to separately designated Board committees because he currently serves as our Chief Executive Officer.

Additionally, Ankit Mahadevia, M.D.

would not qualify as “independent” under applicable Nasdaq Listing Rules applicable to the Board of Directors generally or to separately designated Board committees because he previously served as our Chief Executive Officer within the past three years.

In making such determinations, our Board of Directors considered the relationships that each of our non-employee directors has with our company and all other facts and circumstances deemed relevant in determining independence, including the beneficial ownership of our capital stock by each non-employee director.

Subject to some exceptions, Nasdaq Listing Rule 5605(a)(2) provides that a director will only qualify as an “independent director”

if, in the opinion of our Board of Directors, that person does not have a relationship that would interfere with the exercise of independent judgment in carrying out the responsibilities of a director, and that a director cannot be an “independent director”

if (a) the director is, or in the past three years has been, an employee of ours;

(b) a member of the director’s immediate family is, or in the past three years has been, an executive officer of ours;

(c) the director or a member of the director’s immediate family has received more than $120,000 per year in direct compensation from us within the preceding three years, other than for service as a director or benefits under a retirement plan or non-discretionary compensation (or, for a family member, as an employee);

(d) the director or a member of the director’s immediate family is a current partner of our independent public accounting firm, or has worked for such firm in any capacity on our audit at any time during the past three years;

(e) the director or a member of the director’s immediate family is, or in the past three years has been, employed as an executive officer of a company where one of our executive officers serves on the compensation committee;

or (f) the director or a member of the director’s immediate family is an executive officer, partner or controlling stockholder of a company that makes payments to, or receives payments from, us in an amount which, in any period during our past three fiscal years, exceeds the greater of 5% of the recipient’s consolidated gross revenues for that year or $200,000 (except for payments arising solely from investments in our securities or payments under charitable contribution matching programs).

Additionally, in order to be considered an independent member of an audit committee under Rule 10A-3 under the Exchange Act, a member of an audit committee may not, other than in his or her capacity as a member of the audit committee, the Board of Directors, or any other committee of the Board of Directors, accept, directly or indirectly, any consulting, advisory, or other compensatory fee from the applicable company or any of its subsidiaries or otherwise be an affiliated person of the applicable company or any of its subsidiaries.

To be considered an independent member of the compensation committee under Rule under the Exchange Act, the Board must consider and determine whether a director has a relationship to such company which is material to that director’s ability to be independent from management in connection with the duties of a compensation committee member, including, but not limited to:

the source of compensation of the director, including any consulting advisory or other compensatory fee paid by such company to the director;

and whether the director is affiliated with the company or any of its subsidiaries or affiliates.

Principal Accoun tant Fees and Services.

Principal Accountant Fees and Services.

PricewaterhouseCoopers LLP was our independent registered public accounting firm for the fiscal years ended December 31, 2023 and 2022.

37 unchanged sentences

(Exhibit 4.1)

Description of Registrant’s Securities

(Exhibit 4.2)

2017 Stock Incentive Plan, as amended

6 unchanged sentences

Form of Stock Option Agreement under the 2019 Inducement Equity Incentive Plan, as amended

(Exhibit 4.6)

Form of Restricted Stock Unit Agreement under the 2019 Inducement Equity Incentive Plan, as amended

(Exhibit 4.7)

Form of Director and Officer Indemnification Agreement

1 unchanged sentence

Non-Employee Director Compensation Policy, as amended

(Exhibit 10.7)

Employment Agreement, dated October 20, 2017, by and between the Registrant and Ankit Mahadevia, M.D.

(Exhibit 10.5)

Amendment to Employment Agreement, dated November 10, 2022, by and between the Registrant and Ankit Mahadevia, M.D.

(Exhibit 10.6)

Employment Agreement, dated December 9, 2020, by and between the Registrant and Satyavrat Shukla

Consulting Agreement, dated June 13, 2023, by and between the Registrant and Ankit Mahadevia, M.D.

(Exhibit 10.2)

Amendment to Employment Agreement, dated November 10, 2022, by and between the Registrant and Satyavrat Shukla

Amended and Restated Employment Agreement, dated June 13, 2023, by and between the Registrant and Satyavrat Shukla

(Exhibit 10.3)

1 unchanged sentence

(Exhibit 10.5)

Amendment to Employment Agreement, dated November 10, 2022, by and between the Registrant and Kamal Hamed, M.D., M.P.H., M.B.A.

Amendment to Employment Agreement, dated November 10, 2022, by and between the Registrant and Kamal Hamed, M.D.

(Exhibit 10.8)

3 unchanged sentences

(Exhibit 10.9)

Second Amendment to Employment Agreement, dated as of February 1, 2023, by and between the Registrant and Timothy Keutzer

(Exhibit 10.1)

Employment Agreement, dated November 6, 2020, by and between the Registrant and Tamara Joseph

2 unchanged sentences

(Exhibit 10.10)

Separation Agreement, dated May 3, 2022, by and between the Registrant and Cristina Larkin

(Exhibit 10.1)

Consulting Agreement, dated May 3, 2022, by and between the Registrant and Cristina Larkin

(Exhibit 10.3)

Amendment 1 to Consulting Agreement, dated August 4, 2022, by and between the Registrant and Cristina Larkin

(Exhibit 10.1)

Separation Agreement, dated May 3, 2022, by and between the Registrant and David Melnick, M.D.

(Exhibit 10.2)

Consulting Agreement, dated May 3, 2022, by and between the Registrant and David Melnick, M.D.

(Exhibit 10.4)

Separation Agreement, dated February 9, 2024, by and between the Registrant and Tamara Joseph

Consulting Agreement, dated February 9, 2024, by and between the Registrant and Tamara Joseph

Lease Agreement, dated August 24, 2015, by and between the Registrant and U.S.

22 unchanged sentences

(Exhibit 10.25)

Exchange Agreement, dated November 15, 2018, by and among Spero Therapeutics, Inc.

and Biotechnology Value Fund, L.P., Biotechnology Value Fund II, L.P., Biotechnology Value Trading Fund OS, L.P.

Exchange Agreement, dated November 15, 2018, by and among the Registrant and Biotechnology Value Fund, L.P., Biotechnology Value Fund II, L.P., Biotechnology Value Trading Fund OS, L.P.

and MSI BVF SPV LLC

4 unchanged sentences

(Exhibit 10.2)

License Agreement, dated September 21, 2022, by and between the Registrant and GlaxoSmithKline Intellectual Property (No.

Exclusive License Agreement, dated September 21, 2022, by and between the Registrant and GlaxoSmithKline Intellectual Property (No.

(Exhibit 10.3)

Amendment 1 to Exclusive License Agreement, dated July 4, 2023, by and between the Registrant and GlaxoSmithKline Intellectual Property (No.

Amendment 2 to Exclusive License Agreement, dated December 20, 2023, by and between the Registrant and GlaxoSmithKline Intellectual Property (No.

Share Purchase Agreement, dated September 21, 2022, by and between the Registrant and Glaxo Group Limited

2 unchanged sentences

(Exhibit 10.28)

Securities Purchase Agreement, dated June 12, 2019, by and between the Registrant and Novo Holdings A/S

(Exhibit 10.1)

Form of Proprietary Information and Inventions Assignment Agreement

7 unchanged sentences

Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, by Principal Executive Officer and Principal Financial Officer

Clawback Policy, effective as of November 12, 2023

XBRL Instance Document - the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document

7 unchanged sentences

Confidential materials omitted and filed separately with the SEC.

Certain confidential portions of this Exhibit were omitted by means of marking such portions with brackets (“[***]”) because the identified confidential portions (i) are not material and (ii) is the type that the Registrant treats as private or confidential.

# Management contract or compensatory plan.

5 unchanged sentences

March 13, 2024

/s/ Ankit Mahadevia, M.D.

Ankit Mahadevia, M.D.

/s/ Satyavrat Shukla

Satyavrat Shukla

President and Chief Executive Officer

POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints each of Ankit Mahadevia, M.D.

and Satyavrat Shukla his or her true and lawful attorney-in-fact and agent, with full power of substitution, for him or her and in his or her name, place and stead, in any and all capacities, to sign any and all amendments to this Annual Report on Form 10-K, and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorney-in-fact and agent, full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorney-in-fact and agent, or his substitutes or substitute, may lawfully do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, each of the undersigned has executed this Power of Attorney as of the date indicated opposite his name.

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints each of Satyavrat Shukla and Esther Rajavelu his or her true and lawful attorney-in-fact and agent, with full power of substitution, for him or her and in his or her name, place and stead, in any and all capacities, to sign any and all amendments to this Annual Report on Form 10-K, and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorney-in-fact and agent, full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorney-in-fact and agent, or his substitutes or substitute, may lawfully do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, each of the undersigned has executed this Power of Attorney as of the date indicated opposite his or her name.

Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed below by the following persons on behalf of the registrant in the capacities and on the dates indicated.

/s/ Ankit Mahadevia, M.D.

/s/ Satyavrat Shukla

President, Chief Executive Officer and Director

March 13, 2024

Ankit Mahadevia, M.D.

Satyavrat Shukla

(Principal Executive Officer)

/s/ Satyavrat Shukla

Chief Financial Officer and Treasurer

/s/ Esther Rajavelu

Chief Financial Officer, Chief Business Officer and Treasurer

March 13, 2024

Satyavrat Shukla

Esther Rajavelu

(Principal Financial Officer and Principal Accounting Officer)

5 unchanged sentences

Scott Jackson

/s/ Ankit Mahadevia, M.D.

March 13, 2024

Ankit Mahadevia, M.D.

Pottage, M.D.

12 unchanged sentences

Compared sentence by sentence after normalising whitespace, quotation marks, case and digits, so re-formatting and restated figures do not read as changed language. Wording changes appear as one removal and one addition. The current filing and the prior one are authoritative.

What changed 10-K

Item 9A. Controls and Procedures