UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section Section��14(a) of the

Securities Exchange Act of 1934

(Amendment No.    )

Filed by the Registrant  x☒                             Filed by a Party other than the Registrant  ¨☐

Check the appropriate box:

Regulus Therapeutics Inc.

(Name of Registrant as Specified In Its Charter)

Payment of Filing Fee (Check the appropriate box)

REGULUS THERAPEUTICS INC.

1061410628 Science Center Drive, Suite 225

San Diego, California 92121

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

To Be Held On June 2, 201617, 2020

Dear Stockholder:

You are cordially invited to attend the 20162020 Annual Meeting of Stockholders of Regulus Therapeutics Inc., a Delaware corporation (the “Company”). The meeting will be held on Thursday, June 2, 201617, 2020 at 9:00 a.m. local time at the Company’s principal executive offices located at 1061410628 Science Center Drive, Suite 225, San Diego, CA 92121 for the following purposes:

These items of business are more fully described in the Proxy Statement accompanying this notice.

In light of the ongoingCOVID-19 pandemic and applicable government guidelines, we are planning for the possibility that the annual meeting may be held solely by means of remote communication. If we take this step, we will announce the decision to do so in advance in a press release and details on how to participate will be available at http://ir.regulusrx.com/financial-information/annual-reports as soon as practicable before the annual meeting.

The record date for the annual meeting is April 8, 2016.20, 2020. Only stockholders of record at the close of business on that date may vote at the meeting or any adjournment thereof.

By Order of the Board of Directors

Christopher Aker

Corporate Secretary

San Diego, California

April 22, 201629, 2020

REGULUS THERAPEUTICS INC.

1061410628 Science Center Drive, Suite 225

San Diego, California 92121

PROXY STATEMENT

FOR THE 20162020 ANNUAL MEETING OF STOCKHOLDERS

To be held onBe Held On June 2, 201617, 2020

QUESTIONS AND ANSWERS ABOUT THESE PROXY MATERIALS AND VOTING

Why did I receive a notice regarding the availability of proxy materials on the internet, rather than a full set of proxy materials?

Pursuant to rules adopted by the Securities and Exchange Commission (the “SEC”), we have elected to provide access to our proxy materials over the internet. Accordingly, we have sent you a Notice of Internet Availability of Proxy Materials (a “Notice”) because the Board of Directors (sometimes referred to as the “Board”) of Regulus Therapeutics Inc. (sometimes referred to as “we,” “us,” the “Company” or “Regulus”) is soliciting your proxy to vote at our 20162020 Annual Meeting of Stockholders, including at any adjournments or postponements of the meeting. All stockholders will have the ability to access the proxy materials on the website referred to in the Notice or request to receive a printed set of the proxy materials. Instructions on how to access the proxy materials over the internet or to request a printed copy may be found in the Notice.

The Notice waswill be first mailed to our stockholders of record entitled to vote at the annual meeting on April 22, 2016.29, 2020.

Will I receive any other proxy materials by mail?

We may send you a proxy card, along with a second Notice, on or after May 9, 2020.

How do I attend the annual meeting?

The meeting will be held on Thursday, June 2, 201617, 2020 at 9:00 a.m. local time at 1061410628 Science Center Drive, Suite 225, San Diego, California 92121. Directions to the annual meeting may be found at www.regulusrx.com. Information on how to vote in person at the annual meeting is discussed below.

In light of the ongoingCOVID-19 pandemic and applicable government guidelines, we are planning for the possibility that the annual meeting may be held solely by means of remote communication. If we take this step, we will announce the decision to do so in advance in a press release and details on how to participate will be available at http://ir.regulusrx.com/financial-information/annual-reports as soon as practicable before the annual meeting.

Who can vote at the annual meeting?

Only stockholders of record at the close of business on April 8, 201620, 2020 will be entitled to vote at the annual meeting. On this record date, there were 52,781,00927,608,783 shares of common stock outstanding and entitled to vote.

Stockholder of Record: Shares Registered in Your Name

If on April 8, 201620, 2020 your shares were registered directly in your name with the Company’s transfer agent, Computershare, then you are a stockholder of record. As a stockholder of record, you may vote in person at the meeting or vote by proxy. Whether or not you plan to attend the meeting, we urge you to vote by proxy to ensure your vote is counted.

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Beneficial Owner: Shares Registered in the Name of a Broker or Bank

If on April 8, 201620, 2020 your shares were held, not in your name, but rather in an account at a brokerage firm, bank, dealer or other similar organization, then you are the beneficial owner of shares held in “street name” and received athis Notice from that organization. The organization holding your account is considered to be the stockholder of record for purposes of voting at the annual meeting. As a beneficial owner, you have the right to direct your broker or other agent regarding how to vote the shares in your account. You are also invited to attend the annual meeting. However, since you are not the stockholder of record, you may not vote your shares in person at the meeting unless you request and obtain a valid proxy from your broker or other agent.

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What am I voting on?

There are three matters scheduled for a vote:

What if another matter is properly brought before the meeting?

The Board of Directors knows of no other matters that will be presented for consideration at the annual meeting. If any other matters are properly brought before the meeting, it is the intention of the persons named in the proxy to vote on those matters in accordance with their best judgment.

How do I vote?

You may either vote “For” all the nominees to the Board of Directors or you may “Withhold” your vote for any nominee you specify. For Proposals 2 and 3,all other matters, you may vote “For” or “Against” or abstain from voting.

The procedures for voting are fairly simple:

Stockholder of Record: Shares Registered in Your Name

If you are a stockholder of record, you may vote in person at the annual meeting, by proxy over the telephone, by proxy through the internet or vote by proxy using a proxy card that you may request.request or that we may elect to deliver at a later time. Whether or not you plan to attend the meeting, we urge you to vote by proxy to ensure your vote is counted. You may still attend the meeting and vote in person even if you have already voted by proxy.

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Beneficial Owner: Shares Registered in the Name of Broker or Bank

If you are a beneficial owner of shares registered in the name of your broker, bank, or other agent, you should have received a Notice containing voting instructions from that organization rather than from Regulus. Simply follow the voting instructions in the Notice to ensure that your vote is counted. To vote in person at the annual meeting, you must obtain a valid proxy from your broker, bank or other agent. Follow the instructions from your broker or bank included with these proxy materials, or contact your broker or bank to request a proxy form.

How many votes do I have?

On each matter to be voted upon, you have one vote for each share of common stock you owned as of April 8, 2016.20, 2020.

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What happens if I do not vote?

Stockholder of Record: Shares Registered in Your Name

If you are a stockholder of record and do not vote by completing a proxy card, or by telephone, through the internet, or in person at the annual meeting, your shares will not be voted.

Beneficial Owner: Shares Registered in the Name of Broker or Bank

If you are a beneficial owner and do not instruct your broker, bank, or other agent how to vote your shares, the question of whether your broker or nominee will still be able to vote your shares depends on whether the particular proposal is considered to be a routine matter under applicable rules. Brokers and nominees can use their discretion to vote uninstructed shares with respect to matters that are considered to be routine under applicable rules, but not with respect tonon-routine matters. Under applicable rules and interpretations,non-routine matters are matters that may substantially affect the rights or privileges of stockholders, such as mergers, stockholder proposals, elections of directors (even if not contested), executive compensation (including any advisory stockholder votes on executive compensation and on the frequency of stockholder votes on executive compensation), and certain corporate governance proposals, even if management-supported. Accordingly, your broker or nominee may not vote your shares on ProposalProposals 1 or Proposal 2, without your instructions, but may vote your shares on Proposal 3.

What if I return a proxy card or otherwise vote but do not make specific choices?

If you return a signed and dated proxy card or otherwise vote without marking voting selections, your shares will be voted, as applicable, “For” the election of all sevennine nominees for director named herein, “For” the amendmentapproval of the stockholder advisory vote on the compensation of our Certificate of IncorporationNamed Executive Officers as provideddescribed in Proposal 2, and “For” ratification of the selection by the Audit Committee of the Board of Ernst & Young LLP as the independent registered public accounting firm of the Company for its fiscal year ending 2016.December 31, 2020 as described in Proposal 3. If any other matter is properly presented at the meeting, your proxyholder (one of the individuals named on your proxy card) will vote your shares using his or her best judgment.

Who is paying for this proxy solicitation?

We will pay for the entire cost of soliciting proxies. In addition to these proxy materials, our directors and employees and Broadridge may also solicit proxies in person, by telephone, or by other means of communication. Directors and

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employees will not be paid any additional compensation for soliciting proxies, but Broadridge will be paid its customary fee of approximately $3,000.00 plus out-of-pocket expenses if it solicits proxies. We may also reimburse brokerage firms, banks and other agents for the cost of forwarding proxy materials to beneficial owners.

What does it mean if I receive more than one set of proxy materials?Notice?

If you receive more than one set of proxy materials,Notice, your shares may be registered in more than one name or in different accounts. Please follow the voting instructions on the proxy cardsNotices in the proxy materials to ensure that all of your shares are voted.

Can I change my vote after submitting my proxy?

Stockholder of Record: Shares Registered in Your Name

Yes. You can revoke your proxy at any time before the final vote at the meeting. If you are the record holder of your shares, you may revoke your proxy in any one of the following ways:

What are “brokernon-votes”?

As discussed above, when a beneficial owner of shares held in “street name” does not give instructions to the broker or nominee holding the shares as to how to vote on matters deemed to benon-routine under applicable rules, the broker or nominee may not vote the shares. These unvoted shares are counted as “brokernon-votes.”

How many votes are needed to approve each proposal?

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What is the quorum requirement?

A quorum of stockholders is necessary to hold a valid meeting. A quorum will be present if stockholders holding at least a majority of the shares outstanding shareson the record date and entitled to vote are present at the meeting in person or represented by proxy. On the record date, there were 52,781,00927,608,783 shares outstanding and entitled to vote. Thus, the holders of 26,390,50513,804,392 shares must be present in person or represented by proxy at the meeting to have a quorum.

Your shares will be counted towards the quorum only if you submit a valid proxy (or one is submitted on your behalf by your broker, bank or other nominee) or if you vote in person at the meeting. Abstentions and brokernon-votes will be counted towards the quorum requirement. If there is no quorum, the holders of a majority of shares present at the meeting in person or represented by proxy may adjourn the meeting to another date.

How can I find out the results of the voting at the annual meeting?

Preliminary voting results will be announced at the annual meeting. In addition, final voting results will be published in a current report onForm 8-K that we expect to file within four business days after the completion of the annual meeting. If final voting results are not available to us in time to file aForm 8-K within four business days after the meeting, we intend to file aForm 8-K to publish preliminary results and, within four business days after the final results are known to us, file an additionalForm 8-K to publish the final results.

What proxy materials are available on the internet?

The letter to stockholders, proxy statement, Form 10-K and annual report to stockholders are available at www.regulusrx.com.5

PROPOSAL 1

ELECTION OFOF DIRECTORS

Our Board of Directors currently consists of sixnine directors. There are sevennine nominees for director this year, consisting of our six incumbent directors, and Hugh Rosen, M.D., Ph.D., who our Nominating and Corporate Governance Committee has nominated for election at the annual meeting but does not currently serve on our Board of Directors.directors. Each director to be elected and qualified will hold office until the next annual meeting of stockholders and until his or her successor is elected, or, if sooner, until the director’s death, resignation or removal. Each of the nominees listed below is currently a director of the Company who was previously elected by the stockholders, other than Dr. Rosen.stockholders. Directors are elected by a plurality of the votes of the holders of shares present in person or represented by proxy and entitled to vote on the election of directors. The sevennine nominees receiving the highest number of affirmative votes will be elected. Pursuant to the Company’s Corporate Governance Principles, if the number of votes “For” any of the nine nominees does not exceed a majority of the total number of votes cast (excluding abstentions and brokernon-votes) with respect to such nominee’s election (from the holders of votes of shares either present in person or represented by proxy and entitled to vote), such nominee will promptly tender his or her resignation as a director, and the Nominating and Corporate Governance Committee of the Board will make a recommendation to the Board as to whether to accept or reject such director’s resignation. The Board may accept or reject the resignation in its discretion. Shares represented by executed proxies will be voted, if authority to do so is not withheld, for the election of the nine nominees named below. If any nominee becomes unavailable for election as a result of an unexpected occurrence, your shares may be voted for the election of a substitute nominee proposed by Regulus. Each person nominated for election has agreed to serve if elected. The Company’s management has no reason to believe that any nominee will be unable to serve.

It is the Company’s policy to invite nominees for directors to attend the annual meeting. None of our current directors attended our 20152019 Annual Meeting of Stockholders, except for Dr. Grint.Mr. Hagan.

Nominees

The following is a brief biography of each nominee for director and a discussion of the specific experience, qualifications, attributes or skills of each nominee that led the Nominating and Corporate Governance Committee to recommend that person as a nominee for director, as of the date of this proxy statement.

The Nominating and Corporate Governance Committee seeks to assemble a Board that, as a whole, possesses the appropriate balance of professional and industry knowledge, financial expertise and high-level management experience necessary to oversee and direct the Company’s business. To that end, the Nominating and Corporate Governance Committee has identified and evaluated nominees in the broader context of the

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Board’s overall composition, with the goal of recruiting members who complement and strengthen the skills of other members and who also exhibit integrity, collegiality, sound business judgment and other qualities that the Nominating and Corporate Governance Committee views as critical to effective functioning of the Board. The brief biographies below include information, as of the date of this proxy statement, regarding the specific and particular experience, qualifications, attributes or skills of each director or nominee that led the Nominating and Corporate Governance Committee to recommend that person as a nominee. However, each of the members of the Nominating and Corporate Governance Committee may have a variety of reasons why he or she believes a particular person would be an appropriate nominee for the Board, and these views may differ from the views of other members.

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Stelios Papadopoulos, Ph.D. Chairman of the Board, has served on our Board of Directors since our conversion to a corporation in January 2009 and as our Chairman since June 2013, and prior to that was a director of Regulus Therapeutics LLC since July 2008. Since 1994, Dr. Papadopoulos has served as a director and, since 1998, as Chairman of the Board for Exelixis, Inc., a publicly-heldpublicly held biotechnology company, which heco-founded. Since July 2008, Dr. Papadopoulos has served as a member of the board of directors of Biogen Inc. (formerly Biogen Idec Inc.), a publicly-heldpublicly held biopharmaceutical company, and has served as its chairman of the board of directors since June 2014. From 20002003 to 2011,2018, Dr. Papadopoulos served as a member of the board of directors of Anadys Pharmaceuticals, Inc. prior to its acquisition by F. Hoffman-La Roche, or Roche. Since 2003, Dr. Papadopoulos has served as a member of the board of directors of BG Medicine, Inc., a publicly-held life sciences company. From 2000 to 2006, Dr. Papadopoulos served as Vice Chairman with Cowen and Co., LLC, an investment banking firm. From 1987 to 2000, Dr. Papadopoulos served in several positions with PaineWebber, Incorporated, most recently as Chairman of PaineWebber Development Corp., a PaineWebber subsidiary focusing on biotechnology. Dr. Papadopoulos holds an M.S. in Physics, a Ph.D. in Biophysics and an M.B.A.MBA in Finance from New York University. Our Nominating and Corporate Governance Committee believes that Dr. Papadopoulos is qualified to serve on our Board of Directors due to his knowledge and expertise regarding the biotechnology and healthcare industries, his broad leadership experience on various boards and his experience with financial matters.

David Baltimore, Ph.D. has served on our Board of Directors since our conversion to a corporation in January 2009, and prior to that was a director of Regulus Therapeutics LLC since November 2007. Since 2006, Dr. Baltimore has served as President Emeritus and Robert Andrews Millikan Professor of Biology at the California Institute of Technology, and before that from 1997 to 2006, Dr. Baltimore served as President of the California Institute of Technology. From 1968 to 1972, Dr. Baltimore served as an associate professor at the Massachusetts Institute of Technology, and from 1972 to 1997 was a professor at the Massachusetts Institute of Technology. From 1990 to 1994, Dr. Baltimore served as professor at The Rockefeller University where he also served as the President from July 1990 to December 1991. Since 1997, Dr. Baltimore has served as a director of Amgen Inc., a publicly-heldpublicly held biotechnology company from 1997 to May 2018, and also servesserved as a director of Immune Design Corp., a privately-heldpublicly held biotechnology company, and as chairman of the board of directors of Calimmune,from 1997 until its acquisition by Merck & Co., Inc., a privately-held biotechnology company. in February 2019. In 1975, Dr. Baltimore received the Nobel Prize in Medicine as aco-recipient. Dr. Baltimore holds a Ph.D. in Biology from The Rockefeller University and a B.A. with High Honors in Chemistry from Swarthmore College. Our Nominating and Corporate Governance Committee believes that Dr. Baltimore is qualified to serve on our Board of Directors due to the many years Dr. Baltimore has spent in scientific academia, which has provided him with a deep understanding of our industry and our activities.

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Mark G. FolettaKathryn J. Collier has served on our Board of Directors since January 2013.April 2018. Since August 2015, Mr. FolettaJuly 2019, Ms. Collier has served as the interim Chief Financial Officervice president for audit services of Biocept, Inc.,Sempra Energy, a publicly-traded diagnostics company. Heenergy services holding company whose subsidiaries provide electricity, natural gas and value-added products and services. In this position, Ms. Collier oversees the internal audit function for Sempra Energy, including the Financial Leadership Program and audit oversight of Sempra’s operating companies. From March 2019 to July 2019, Ms. Collier served as the chief strategy and origination officer for Sempra LNG, a wholly-owned subsidiary of Sempra Energy. From August 2018 to March 2019, Ms. Collier served as chief financial officer and chief administrative officer for Sempra North America Infrastructure. Ms. Collier also previously served as Senior Vice President, Financevice president and Chief Financial Officer of Amylin Pharmaceuticals, Inc.treasurer for Sempra Energy from March 2006 through Amylin’s acquisition by Bristol Myers-Squibb Company inApril 2012 to August 2012.2018. Prior to joining AmylinSempra Energy in 2000, Mr. Foletta2012, Ms. Collier held several executive positions within global corporate and investment banking at Bank of America Merrill Lynch. Ms. Collier holds a number of management positions with Intermark, Inc. and Triton Group Ltd. and served as an Audit Manager with Ernst & Young. Mr. Foletta served as a director of Anadys Pharmaceuticals, Inc., a publicly-held biopharmaceutical company,bachelor’s degree in accounting from September 2005 through November 2011 (acquired by Roche) and of Ambit Biosciences during 2014 until its acquisition by Daiicho Sankyo. He is currently a member of the Board of Directors and Audit Committee of AMN Healthcare Services, Inc., a publicly-traded health services company, DexCom, Inc., a publicly-held healthcare company, and ViaCyte Inc., a privately-held biotechnology company. Mr. Foletta received a B.A. in Business Economics from theValparaiso University, of California, Santa Barbara. He is a Certified Public Accountant and a member of the Corporate Directors Forum.Valparaiso, Indiana. Our Nominating and Corporate Governance Committee believes that Mr. Foletta’s extensive financial and operational experience in the biotechnology industry qualifies himMs. Collier is qualified to serve on our Board of Directors.Directors due to her extensive financial and operational experience, her experience in investment banking and her corporate governance experience with various boards.

Paul C. Grint, M.D.Joseph P. Haganhas served as our President and Chief Executive Officer and on our Board of Directorsprincipal executive officer since June 2015, and prior to that wasMay 2017. Mr. Hagan previously served as our Chief MedicalOperating Officer, sinceprincipal financial officer and principal accounting officer from January 2016 to May 2017. From June 2014. From February 2011 to June 2014, Dr. Grintthrough December 2015, Mr. Hagan served as the Executive Vice President, Chief Financial Officer and Chief Business Officer of Cerexa,Orexigen Therapeutics, Inc., a wholly owned subsidiary of Forest Laboratories, Inc., a pharmaceutical company, where he was responsible for the oversight of anti-infective product development. Before that, Dr. Grint From May 2009 to June 2011, Mr. Hagan served as Orexigen’s Senior Vice President, Corporate Development, Strategy and Communications. From September 1998 to April 2008,

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Mr. Hagan served as Managing Director of ResearchAmgen Ventures. Prior to starting the Amgen Ventures Fund, Mr. Hagan served as Head of corporate development for Amgen Inc. Before joining Amgen, Mr. Hagan spent five years in the bioengineering labs at Forest Research Institute, Inc., the scientific development subsidiary of Forest Laboratories, Inc., from January 2009 to February 2011, as Chief Medical Officer of Kalypsys, Inc., a biopharmaceutical company, from 2006 to 2008,Genzyme and as Senior Vice President and Chief Medical Officer of Zephyr Sciences, Inc., a biopharmaceutical company, during 2006. Dr. Grint also previously served in similar executive level positions at Pfizer Inc., IDEC Pharmaceuticals Corporation, and Schering-Plough Corporation. Dr. GrintAdvanced Tissue Sciences. Mr. Hagan has served on the board of directors of Synedgen,Zosano Pharma, a privately-held bio-pharmaceuticalpublicly-traded biotechnology company, since December 2014May 2015 and AmpliPhi Biosciences Corporation, a publicly-held biopharmaceutical company, since November 2014. Dr. Grint also served on the Boardboard of Directors of Illumina,Aurinia Pharmaceuticals, Inc., since February 2018. He received an M.B.A. from April 2005 to May 2013. Dr. Grint receivedNortheastern University and a B.S. in Medical SciencePhysiology and Neuroscience from St. Mary’s Hospital in London and his medical degree from St. Bartholomew’s Hospital Medical College at the University of London. Dr. Grint is a Fellow of the Royal College of Pathologists, a member of numerous professional and medical societies, and the author or co-author of over 50 scientific publications.California, San Diego. Our Nominating and Corporate Governance Committee believes that Dr. Grint’sMr. Hagan’s expertise in clinicalbusiness development, commercialization and commercializationfinancing of novel therapeuticspublic companies qualify him to serve on our Board of Directors.

Jake R. Nunn has served on our Board of Directors since June 2019. Mr. Nunn is currently a venture advisor at New Enterprise Associates, Inc., a venture capital firm, where he was a partner from June 2006 until January 2019. Prior to joining NEA, he served as a partner and an analyst for the MPM BioEquities Fund, a life sciences fund at MPM Capital, L.P., a private equity firm. Previously, he was a healthcare research analyst and portfolio manager at Franklin Templeton Investments and an investment banker with Alex. Brown & Sons. Mr. Nunn has served on the board of directors of Trevena, Inc., a publicly-held biotechnology company focused on CNS since July 2013 and Addex Therapeutics Ltd., a publicly-held biopharmaceutical company focused on allosteric modulators for neurological disorders since June 2019. Mr. Nunn served on the board of directors of Dermira, Inc., a publicly-held biopharmaceutical company focused on dermatology, from May 2011 until its acquisition by Eli Lilly and Company in February 2020. From 2009 to May 2015, Mr. Nunn served on the board of directors of Hyperion Therapeutics, Inc. and from 2008 to February 2016, Mr. Nunn served on the board of directors of TriVascular Technologies, Inc. Mr. Nunn received his A.B. in economics from Dartmouth College and his M.B.A. from the Stanford Graduate School of Business. He also holds the Chartered Financial Analyst designation and is a member of the CFA Society of San Francisco. Our Nominating and Corporate Governance Committee believes that Mr. Nunn is qualified to serve on our Board of Directors due to his extensive financial experience, his experience in investment banking and his corporate governance experience with various boards.

William H. Rastetter, Ph.D. has served on our Board of Directors since April 2013. From 2006 to February 2013, Dr. Rastetter served as a partner in the venture capital firm, Venrock. He served as Chief Executive Officer of IDEC Pharmaceuticals from December 1986 through November 2003, and as Chairman from May 1996 to November 2003. Upon the merger of IDEC Pharmaceuticals and Biogen in November 2003, Dr. Rastetter served as Executive Chairman of Biogen Idec until the end of 2005. Dr. Rastetter served as chairman of the board of Illumina, Inc., a publicly held biotechnology company, from 2005 to January 2016 and served on its board of directors from 1998 to January 2016. He was a founder of Receptos, Inc. in 2009 and served as its chairman until the sale of the publicly held company to Celgene in 2015. Currently, he serveshas served as the chairman of the board of directors of Fate Therapeutics, Inc., a publicly-heldpublicly held biotechnology company, since November 2011; chairman of the board of directors of Neurocrine Biosciences, Inc., a publicly-heldpublicly held biotechnology company, lead outside directorsince May 2011 and on its board of Cerulean Pharma Inc., a publicly-held biotechnology company anddirectors since February 2010; on the board of directors of Grail, Inc,Inc., a majority-owned subsidiaryprivately-held company, since January 2016, and as its chairman from August 2017 to November 2018. Dr. Rastetter served on the board of Illumina, Inc..directors of Cerulean Pharma Inc., a publicly held biotechnology company since January 2014, as its lead independent director from April 2014 to June 2016, and as its chairman from June 2016 until July 2017 when Cerulean and Daré Bioscience Inc. completed a reverse merger and he currently serves on the board of the surviving company, Daré Bioscience Inc., a publicly-traded company. In addition, he serves as an advisor to Leerink Partners, a healthcare-focused investment bank, and on the board of trustees of Caltech.as an advisor to Illumina Ventures. He is the author of numerous scientific papers and patent applications in the fields of organic and bioorganic chemistry, protein and enzyme engineering, and biotechnology. Dr. Rastetter holds an S.B. in Chemistry from the Massachusetts Institute of Technology and received his M.A. and Ph.D. in Chemistry from Harvard University. Our Nominating and Corporate Governance Committee believes that Dr. Rastetter’s knowledge and expertise regarding the biotechnology industry and his leadership experience on various biotechnology company boards of directors qualifies him to serve on our Board of Directors.

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Hugh Rosen, M.D., Ph.D. is a nominee tohas served on our Board of Directors.Directors since June 2016. Since 2002,April 2017, Dr. Rosen has beenserved as the President and Chairman of the Board of Activx Biosciences, Inc., a wholly owned

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biopharmaceutical subsidiary of Kyorin Pharmaceutical Co., Ltd. From 2002 until March 2017, Dr. Rosen served as a Professor of Chemical Physiology at The Scripps Research Institute (TSRI) in La Jolla, California where he focusesfocused on pursuing his primary interests in lymphocyte trafficking and barrier regulation by signaling lipids, and contributing towards the development of translational infrastructure at TSRI. He also servesserved as Chairman of the Committee for Advanced Human Therapeutics of TSRI. Prior to joining The Scripps Research Institute, Dr. Rosen served in various capacities with Merck Research Laboratories most recently serving as Executive Director in Immunology, Rheumatology and Infectious Diseases and Chair of the Worldwide Business Strategy Team for Antibacterials and Antifungals, reporting to the Management Committee. Dr. Rosen was a scientific founder of Receptos, Inc., now a wholly owned biopharmaceutical subsidiary of Celgene Corporation, and currently serves on the Receptos Scientific Advisory Board. He also serves on the Scientific Advisory Board of ActivX Biosciences Inc., a wholly owned biopharmaceutical subsidiary of Kyorin Pharmaceuticals Co., Ltd.Blackthorn Therapeutics. He received his M.D. from the University of Cape Town, South Africa and his Ph.D. in Physiological Sciences from Oxford. Our Nominating and Corporate Governance Committee believes that Dr. Rosen is qualified to serve on our Board of Directors due to the many years Dr. Rosen has spent in scientific academia as well as the biopharmaceutical industry, which has provided him with a deep understanding of our industry and our activities.

Douglas E. Williams,Simos Simeonidis, Ph.D. has served on our Board of Directors since November 2012. HeJune 2019. Since June 2017, Dr. Simeonidis has served as a Partner at Sarissa Capital. Prior to joining Sarissa Capital, he was a Managing Director and Senior Biotechnology Analyst at the Chief Executive OfficerRoyal Bank of Canada (RBC) in New York from July 2014 to June 2017. Dr. Simeonidis spent more than a decade covering the biotechnology sector as an analyst at a number of investment banks, including Cowen and President of Codiak Biosciences, Inc. since November 2015. HeCompany, First Albany Capital and Morgan Stanley. In addition to his investment management and financial expertise, Dr. Simeonidis combines both biopharmaceutical industry and biomedical research expertise, having worked at Novartis in Business Development and Strategic Planning, and prior to his corporate career, having served as Executive Vice Presidenta faculty member at Harvard Medical School. Dr. Simeonidis received his BS in Biology from Loyola University Chicago, and his MA, MPhil and PhD degrees in Cellular, Molecular and Biophysical Sciences from Columbia University’s College of ResearchPhysicians & Surgeons. He completed his Postdoctoral Fellowship at the laboratory of Professor Tucker Collins at Harvard Medical School and Development at Biogen, a publicly-held biopharmaceutical company, from January 2011 to July 2015. Dr. Williams was the Chief Executive OfficerBrigham and member of the Board of Directors of ZymoGenetics, Inc., a publicly-held biopharmaceutical company, from January 2009 until November 2010 (acquired by Bristol-Myers Squibb). He also served as President of ZymoGenetics, Inc. from 2007 to 2009 and as Chief Scientific Officer and Executive Vice President from 2004 to 2007. Previously,Women’s Hospital, where he was the Chief Scientific Officer and Executive Vice President of Research and Development at Seattle Genetics Inc., a publicly-held biotechnology company, Head of Health and Strategic Development at Genesis Research & Development Corp. Ltd, and Senior Vice President and Washington Site Leader at Amgen Inc., a publicly-held biopharmaceutical company. Dr. Williams also served in a series of scientific and senior leadership positions over a decade at Immunex Corp., a publicly held biopharmaceutical company (acquired by Amgen, Inc.) including Executive Vice President and Chief Technology Officer, Senior Vice President of Discovery Research and Vice President of Research and Development. Before entering the biotechnology industry, Dr. Williams servedworked on the facultytranscriptional regulation of the Indiana University School of Medicine and the Department of Laboratory Medicinegene expression. Dr. Simeonidis also holds an MBA in Healthcare Management at the Roswell Park Memorial Institute in Buffalo, New York. He holds a Ph.D. in Physiology from the State UniversityWharton School of New York at Buffalo, Roswell Park Memorial Institute Division and a B.S. magna cum laude in Biological Sciences from the University of Massachusetts, Lowell.Pennsylvania. Our Nominating and Corporate Governance Committee believes that Dr. WilliamsSimeonidis is qualified to serve on our Board of Directors due to his extensive operational and leadership experience in investment banking and as an analyst covering the biotechnology industry.life sciences industry, his prior employment in the biopharmaceutical industry, and his medical and scientific background.

Pascale Witz, MBA, MSc has served on our Board of Directors since June 2017. From September 2015 through May 2016, Ms. Witz served as the Executive Vice President, Diabetes & Cardiovascular for Sanofi, S.A. Prior to that position, Ms. Witz served as the Executive Vice President, Global Divisions and Strategic Development, commencing in July 2013. Commencing in 1996, Ms. Witz was employed in positions of increasing responsibility with GE Healthcare, most recently serving as the President and CEO of Medical Diagnostics from March 2009 through June 2013. Ms. Witz has served on the board of Perkin Elmer, a publicly-held global scientific technology and life science research company, since October 2017, Horizon Pharma, a publicly-held pharmaceutical company, since August 2017 and Fresenius Medical Care AG & Co. KGaA, a publicly-held world leader dialysis company since May 2016. Ms. Witz also served on the board of TESARO, Inc., a publicly-held biopharmaceutical company from May 2018 until its acquisition by GlaxoSmithKline plc in January 2019 and from May 2016 to April 2018, served on the board of Savencia SA, a publicly held global food and dairy company. Ms. Witz received her MSc in Life Sciences & Engineering from the Institut National des Sciences Appliquées de Lyon, France and an MBA from INSEAD, Fontainebleau, France. She was also a Ph.D. student in Molecular Biology at the Centre National de la Recherche Scientifique, Strasbourg, France. Our Nominating and Corporate Governance Committee believes that Ms. Witz is qualified to serve on our Board of Directors due to the many years she has spent in the biopharmaceutical industry, which has provided her with a deep understanding of our industry and our activities.

THE BOARDOF DIRECTORS RECOMMENDS

A VOTEFORFOR EACH NAMED NOMINEE

INDEPENDENCE

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INDEPENDENCE OF THE BOARD THE BOARD OF DIRECTORS DIRECTORS

As required under the NASDAQNasdaq Stock Market (“NASDAQ”Nasdaq”) listing standards, a majority of the members of a listed company’s Board of Directors must qualify as “independent,” as affirmatively determined by the Board of Directors. The Board consults with the Company’s counsel to ensure that the Board’s determinations are consistent with relevant securities and other laws and regulations regarding the definition of “independent,” including those set forth in pertinent listing standards of NASDAQ,Nasdaq, as in effect from time to time.

Consistent with these considerations, after review of all relevant identified transactions or relationships between each director, or any of his family members, and the Company, its senior management and its independent auditors, the Board has affirmatively determined that the following foureight directors are independent

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directors within the meaning of the applicable NASDAQNasdaq listing standards: Dr. Baltimore, Ms. Collier, Mr. Foletta,Nunn, Dr. Papadopoulos, Dr. Rastetter, Dr. Rosen, Dr. Simeonidis and Dr. Rastetter.Ms. Witz. In making this determination, the Board found that none of these directors or nominees for director had a material or other disqualifying relationship with the Company.

BOARD LEADERSHIP STRUCTUREBOARD LEADERSHIP STRUCTURE

Our Board of Directors is currently chaired by Stelios Papadopoulos, 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 the Board of Directors from management, creates an environment that encourages objective oversight of management’s performance and enhances the effectiveness of the Board of Directors as a whole. As such, Dr. GrintMr. Hagan serves as our President and Chief Executive Officer while Dr. Papadopoulos serves as our Chairman of the Board of Directors but is not an officer. We expect and intend the positions of Chairman of the Board of Directors and Chief Executive Officer to continue to be held by separate individuals in the future.

ROLEROLE OFTHE BOARD BOARD IN RISK OVERSIGHT RISK OVERSIGHT

One of the key functions of our Board of Directors is informed oversight of our risk management process. The Board of Directors does not have a standing risk management committee, but rather administers this oversight function directly through the Board of Directors as a whole, as well as through various standing committees of our Board of Directors that address risks inherent in their respective areas of oversight. In particular, our Board of Directors is responsible for monitoring and assessing strategic risk exposure, and our Audit Committee has the responsibility to consider and discuss our major financial risk exposures and the steps our management has taken to monitor and control these exposures, including guidelines and policies to govern the process by which risk assessment and management is undertaken. The Audit Committee also monitors compliance with legal and regulatory requirements. Our Nominating and Corporate Governance Committee monitors the effectiveness of our corporate governance practices, including whether they are successful in preventing illegal or improper liability-creating conduct. Our Compensation Committee assesses and monitors whether any of our compensation policies and programs has the potential to encourage excessive risk-taking.

MEETINGSAs a result of theCOVID-19 pandemic, we have and may in the future experience disruptions that could severely impact our business, preclinical studies and clinical trials. Given the evolving nature of the pandemic, our senior management and our Board of Directors are communicating and meeting more frequently to monitor potential business impacts and further strategic planning.

MEETINGS OF THE BOARD THE BOARD OF DIRECTORS DIRECTORS

The Board of Directors met fivenine times during the last fiscal year and four times in executive session. All directors who served in 20152019 attended at least 75% of the aggregate number of meetings of the Board and of the committees on which they served, held during the portion of the last fiscal year for which they were directors or committee members, respectively.

INFORMATION REGARDING COMMITTEES

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INFORMATION REGARDING COMMITTEES OF THE BOARD THE BOARD OF DIRECTORS DIRECTORS

The Board has three committees:maintains an Audit Committee, a Compensation Committee and a Nominating and Corporate Governance Committee. The following table provides membership and meeting information for the year ended December 31, 20152019 for each of the Board committees:

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Below is a description of each committee of the Board of Directors. Each of the committees has authority to engage legal counsel or other experts or consultants, as it deems appropriate to carry out its responsibilities. Our Board of Directors has determined that each member of each committee meets the applicable NASDAQNasdaq rules and regulations regarding “independence” and that each member is free of any relationship that would impair his or her individual exercise of independent judgment with regard to the Company.

Audit Committee

The Audit Committee of our Board of Directors was established by our Board of Directors in accordance with Section 3(a)(58)(A) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), to oversee the Company’s corporate accounting and financial reporting processes and audits of its financial statements. For this purpose, our Audit Committee performs several functions. Our Audit Committee evaluates the performance of and assesses the qualifications of the independent auditors; determines and approves the engagement of the independent auditors; determines whether to retain or terminate the existing independent auditors or to appoint and engage new independent auditors; reviews and approves the retention of the independent auditors to perform any proposed permissiblenon-audit services; monitors the rotation of partners of the independent auditors on the Company’s audit engagement team as required by law; reviews and approves or rejects transactions between the Company and any related persons; confers with management and the independent auditors regarding the effectiveness of internal controls over financial reporting; establishes procedures, as required under applicable law, for the receipt, retention and treatment of complaints received by the Company regarding accounting,

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internal accounting controls or auditing matters and the confidential and anonymous submission by employees of concerns regarding questionable accounting or auditing matters; and meets to review the Company’s annual audited financial statements and quarterly financial statements with management and the independent auditor, including a review of the Company’s disclosures under “Management’s Discussion and Analysis of Financial Condition and Results of Operations.”

Our Audit Committee is currently composed of three directors: Ms. Collier, Mr. Foletta, Dr. PapadopoulosNunn and Dr. Rastetter.Papadopoulos. The Audit Committee met five times during the last fiscal year. Our Board of Directors has adopted a written charter of the Audit Committee that is available to stockholders on the Company’s website at www.regulusrx.com. Our Board of Directors reviews the NASDAQNasdaq listing standards definition of independence for Audit Committee members on an annual basis and has determined that all members of our Audit Committee are independent (as independence is currently defined in Rule 5605(c)(2)(A) of the NASDAQNasdaq listing standards). Our Board of Directors has determined that each member of our Audit Committee meets the requirements for independence under the NASDAQ listing standards.

Our Board of Directors has determined that Mr. FolettaMs. Collier qualifies as an “audit committee financial expert,” as defined in applicable SEC rules. Our Board of Directors has made a qualitative assessment of Mr. Foletta’sMs. Collier’s level of knowledge and experience based on a number of factors, including hisher formal education, hisher experience in the investment banking industry and as the holder of various positions with responsibility for finance of a chief financial officer forsubsidiary of a public company and his service as an Audit Manager with Ernst & Young. In addition to the Audit Committee, Mr. Foletta also serves on the audit committee of AMN Healthcare Services and during 2014 served on the Audit Committee of Ambit Biosciences. Our Board of Directors has determined that this simultaneous service does not impair Mr. Foletta’s ability to effectively serve on our Audit Committee.major publicly-traded energy services holding company.

Report of the Audit Committee of the Board of Directors*

The Audit Committee has reviewed and discussed the audited financial statements for the fiscal year ended December 31, 20152019 with management of the Company. The Audit Committee has discussed with the independent registered public accounting firm the matters required to be discussed by Auditing Standard No. 16,Communications with Audit Committees, as adopted bythe applicable requirements of the Public Company Accounting Oversight Board (“PCAOB”). and the SEC. The Audit Committee has also received the written disclosures and the letter from the independent registered public accounting firm required by applicable requirements of the PCAOB regarding the independent accountants’ communications with the Audit Committee concerning independence, and has discussed with the

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independent registered public accounting firm the accounting firm’s independence. Based on the foregoing, the Audit Committee has recommended to the Board of Directors that the audited financial statements be included in the Company’s Annual Report onForm 10-K for the fiscal year ended December 31, 2015.2019.

Mr. Mark G. FolettaMs. Kathryn J. Collier (Chair)

Dr. Stelios Papadopoulos

Dr. William H. RastetterJake Nunn

Compensation Committee

The Compensation Committee is currently composed of twothree directors: Dr. BaltimoreRastetter, Dr. Rosen and Dr. Rastetter.Ms. Witz. The Board of Directors reviews the NASDAQNasdaq listing standards definition of independence for Compensation Committee members on an annual basis and has determined that all members of the Company’s Compensation Committee are independent (as independence is currently defined in Rule 5605(d)(2)(A of the NASDAQNasdaq listing standards). The Compensation Committee met eight times during the last fiscal year. The Compensation Committee has adopted a written charter that is available to stockholders on the Company’s website at www.regulusrx.com.

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The Compensation Committee acts on behalf of the Board to review, adopt and/or recommend for adoption and oversee the Company’s compensation strategy, policies, plans and programs, including:programs. The functions of the Compensation Committee include, among other things:

Compensation Committee Processes and Procedures

Typically, the Compensation Committee meets at least twice annually and with greater frequency if necessary. The agenda for each meeting is usually developed by the Chair of the Compensation Committee, in consultation with the Chief Executive Officer. The Compensation Committee meets regularly in executive session. However, from time to time, various members of management and other employees as well as outside

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advisors or consultants may be invited by the Compensation Committee to make presentations, to provide financial or other background information or advice or to otherwise participate in Compensation Committee meetings. The Chief Executive Officer may not participate in, or be present during, any deliberations or determinations of the Compensation Committee regarding his compensation. The charter of the Compensation Committee grants the Compensation Committee full access to all books, records, facilities and personnel of the Company, as well as authority to obtain, at the expense of the Company, advice and assistance from internal and external legal, accounting or other advisors and consultants and other external resources that the Compensation Committee considers necessary or appropriate in the performance of its duties. In particular, the Compensation Committee has the sole authority to retain compensation consultants to assist in its evaluation of executive and director compensation, including the authority to approve the consultant’s reasonable fees and other retention terms.

During the past fiscal year 2019, the Compensation Committee engaged Aon/Radford as a compensation consultant. The Committee engaged Aon/Radford to provide a competitive assessment of the Company’s

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executive compensation program compared to executive compensation paid to executives at selected publicly-tradedpublicly traded peer companies. Following a gap analysis of the peer companies, Aon/Radford made certain recommendations to the Compensation Committee to make modest increases in the level of equity grants to the Company’s executive team and to increase annual cash compensation for certain Company executives and Board Committee members who were paid below the median compared to the peer companies. The Compensation Committee analyzed whether the work of Aon/Radford as a compensation consultant raised any conflict of interest, taking into consideration the following factors: (i) the provision of other services to the Company by the compensation consultant; (ii) the amount of fees from the Company paid to the compensation consultant as a percentage of the firm’s total revenue; (iii) the policies and procedures of the compensation consultant that are designed to prevent conflicts of interest; (iv) any business or personal relationship of the compensation consultant or the individual compensation advisors employed by this firm with an executive officer of the Company; (v) any business or personal relationship of the individual compensation advisors with any member of the Compensation Committee; and (vi) any stock of the Company owned by the compensation consultant or the individual compensation advisors employed by this firm. The Compensation Committee concluded, based on its analysis of the above factors, that the work of Aon/Radford and the individual compensation advisors employed by this firm as a compensation consultant to the Company has not created any conflict of interest.

Under its charter, the Compensation Committee may form, and delegate authority to, subcommittees as appropriate. In 2012, the Compensation Committee formed aNon-Management Stock Option Committee, currently composed of Dr. Grint,Mr. Hagan, to which it delegated authority to grant, without any further action required by the Compensation Committee, stock optionsawards to employees who are not officers of the Company. The purpose of this delegation of authority is to enhance the flexibility of option administration within the Company and to facilitate the timely grant of options tonon-management employees, particularly new employees, within specified limits approved by the Compensation Committee. In particular, the subcommittee may grant options only withinpre-approved guidelines and not to any employee who will have a vice president title or higher. Typically, as part of its oversight function, the Committee will review on a regular basis the list of grants made by the subcommittee. During fiscal year 2015,2019, the subcommittee exercised its authority to grant options and stock awards to purchase an aggregate of 786,000578,850 shares of the Company’s common stock tonon-officer employees.

Historically, the Compensation Committee has made most of the significant adjustments to annual compensation, determined bonus and equity awards and established new performance objectives at one or more meetings held during the last quarter of the year. However, the Compensation Committee also considers matters related to individual compensation, such as compensation for new executive hires, as well as high-level strategic issues, such as the efficacy of the Company’s compensation strategy, potential modifications to that strategy and new trends, plans or approaches to compensation, at various meetings throughout the year. Generally, the Compensation Committee’s process comprises two related elements: the determination of compensation levels and the establishment of performance objectives for the current year. For executives other than the Chief Executive Officer, the Compensation Committee solicits and considers evaluations and recommendations

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submitted to the Committee by the Chief Executive Officer. In the case of the Chief Executive Officer, the evaluation of his performance is conducted by the Compensation Committee, which determines any adjustments to his compensation as well as awards to be granted. For all executives and directors as part of its deliberations, the Compensation Committee may review and consider, as appropriate, materials such as financial reports and projections, operational data, tax and accounting information, tally sheets that set forth the total compensation that may become payable to executives in various hypothetical scenarios, executive and director stock ownership information, company stock performance data, analyses of historical executive compensation levels and current Company-wide compensation levels and recommendations of the Company’s Senior Vice President, Human Capital,Legal Affairs, including analyses of executive and director compensation paid at other companies identified by the Company’s Senior Vice President, Human Capital.Legal Affairs.

Nominating and Corporate Governance Committee

The Nominating and Corporate Governance Committee of the Board of Directors is responsible for identifying, reviewing and evaluating candidates to serve as directors of the Company (consistent with criteria

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approved by the Board), reviewing and evaluating incumbent directors, recommending to the Board for selection candidates for election to the Board of Directors, making recommendations to the Board regarding the membership of the committees of the Board, assessing the performance of the Board, and monitoring the Company’s adherence to its Code of Business Conduct and Ethics.

The Nominating and Corporate Governance Committee is composed of three directors: Dr. Baltimore, Mr. FolettaDr. Papadopoulos and Dr. Rastetter.Simeonidis. All members of the Nominating and Corporate Governance Committee are independent (as independence is currently defined in Rule 5605(a)(2) of the NASDAQNasdaq listing standards). The Nominating and Corporate Governance Committee met twiceonce during 2015.2019. The Nominating and Corporate Governance Committee has adopted a written charter that is available to stockholders on the Company’s website and www.regulusrx.com.

The Nominating and Corporate Governance Committee believes that candidates for director, both individually and collectively, can and do provide the integrity, experience, judgment, commitment (including having sufficient time to devote to the Company and level of participation), skills, diversity and expertise appropriate for the Company. In assessing the directors, both individually and collectively, the Nominating and Corporate Governance Committee may consider the current needs of the Board and the Company to maintain a balance of knowledge, experience and capability in various areas. However, the Nominating and Corporate Governance Committee retains the right to modify these qualifications from time to time. Candidates for director nominees are reviewed in the context of the current composition of the Board, the operating requirements of the Company and the long-term interests of stockholders. In conducting this assessment, the Nominating and Corporate Governance Committee typically considers diversity, age, skills and such other factors as it deems appropriate given the current needs of the Board and the Company, to maintain a balance of knowledge, experience and capability. In the case of incumbent directors whose terms of office are set to expire, the Nominating and Corporate Governance Committee reviews these directors’ overall service to the Company during their terms, including the number of meetings attended, level of participation, quality of performance and any other relationships and transactions that might impair the directors’ independence. In the case of new director candidates, the Nominating and Corporate Governance Committee also determines whether the nominee is independent for NASDAQNasdaq purposes, which determination is based upon applicable NASDAQNasdaq listing standards, applicable SEC rules and regulations and the advice of counsel, if necessary. The Nominating and Corporate Governance Committee then uses its network of contacts to compile a list of potential candidates, but may also engage, if it deems appropriate, a professional search firm. The Nominating and Corporate Governance Committee conducts any appropriate and necessary inquiries into the backgrounds and qualifications of possible candidates after considering the function and needs of the Board. The Nominating and Corporate Governance Committee meets to discuss and consider the candidates’ qualifications and then selects a nominee for recommendation to the Board by majority vote.

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The Nominating and Corporate Governance Committee will consider director candidates recommended by stockholders. The Nominating and Corporate Governance Committee does not intend to alter the manner in which it evaluates candidates, including the minimum criteria set forth above, based on whether or not the candidate was recommended by a stockholder. Stockholders who wish to recommend individuals for consideration by the Nominating and Corporate Governance Committee to become nominees for election to the Board may do so by delivering a written recommendation to the Nominating and Corporate Governance Committee at the Company’s principal executive offices, Attn: Secretary, no later than the 90th day and no earlier than the 120th day prior to the one year anniversary of the preceding year’s annual meeting. Submissions must include (1) the name and address of the Company stockholder on whose behalf the submission is made; (2) the number of Company shares that are owned beneficially by such stockholder as of the date of the submission; (3) the full name of the proposed candidate; (4) a description of the proposed candidate’s business experience for at least the previous five years; (5) the complete biographical information for the proposed candidate; (6) a description of the proposed candidate’s qualifications as a director; and (7) any other information required by the Company Bylaws. The Company may require any proposed nominee to furnish such other information as it may reasonably require to determine the eligibility of such proposed nominee to serve as an independent director of the Company or that could be material to a reasonable stockholder’s understanding of the independence, or lack thereof, of such proposed nominee.

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Stockholder Communications with the Board of Directors

The Company’s Board has adopted a formal process by which stockholders may communicate with the Board or any of its directors. Stockholders who wish to communicate with the Board may do so by sending written communications addressed to the Secretary of Regulus Therapeutics Inc. at the Company’s principal executive offices. Each communication must set forth: the name and address of the Company stockholder on whose behalf the communication is sent; and the number of Company shares that are owned beneficially by such stockholder as of the date of the communication. Each communication will be reviewed by the Company’s Secretary to determine whether it is appropriate for presentation to the Board or relevant directors.

Communications determined by the Company’s Secretary to be appropriate for presentation to the Board or any relevant directors are submitted to the Board or relevant directors on a periodic basis.

Code of Ethics

The Company has adopted a Code of Business Conduct and Ethics that applies to all directors, officers (including our principal executive officer, principal financial officer and principal accounting officer) and employees. The Code of Business Conduct and Ethics is available on the Company’s website at www.regulusrx.com under the Corporate Governance section of our Investor Relations page. If the Company makes any substantive amendments to the Code of Business Conduct and Ethics that applies to our principal executive officer, principal financial officer, principal accounting officer, controller or persons performing similar functions, or grants any waiver from a provision of the Code of Business Conduct and Ethics to any of these specified individuals that is required to be disclosed pursuant to SEC rules and regulations, the Company will promptly disclose the nature of the amendment or waiver on its website.

Section 16(a) Beneficial Ownership Reporting ComplianceHedging Policy

Section 16(a)The Company’s insider trading and window period policy provides that no officer, director, other employee or consultant of the Exchange Act requiresCompany may engage in short sales, transactions in put or call options, hedging transactions or other inherently speculative transactions with respect to the Company’s directors and executive officers, and persons who own more than ten percentstock at any time. In addition, no officer, director, other employee or consultant of a registered classthe Company may margin, or make any offer to margin, any of the Company’s equity securities, to file with the SEC initial reports of ownership and reports of changes in ownership of common stock, and other equity securities of the Company. Officers, directors and greater than ten percent stockholders are required by SEC regulation to furnish the Company with copies of all Section 16(a) forms they file.

To the Company’s knowledge, based solely on a review of the copies ofincluding without limitation, borrowing against such reports furnished to the Company and written representations that no other reports were required, during the fiscal year ended December 31, 2015, all Section 16(a) filing requirements applicable to its officers, directors and greater than ten percent beneficial owners were complied with; except that each of Drs. Baltimore, Papadopoulos, Carter, Grint, Rastetter, Williams and Mr. Foletta failed to timely file one report each, each report covering one transaction.

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PROPOSAL 2

APPROVALDVISORY VOTEOFON AEMENDMENTTO AMENDEDAND RESTATEDXECUTIVE CERTIFICATEOF INCORPORATIONOMPENSATION

At the 2018 Annual Meeting of Stockholders, the stockholders indicated their preference that the Company solicit anon-binding advisory vote on the compensation of the named executive officers, commonly referred to as a“say-on-pay vote,” every year. The Board has adopted a policy that is consistent with that preference.

This vote is not intended to address any specific item of compensation, but rather the overall compensation of the Company’s Amendednamed executive officers and Restated Certificatethe philosophy, policies and practices described in this proxy statement. The compensation of Incorporation (the “Certificate of Incorporation”) currently providesthe Company’s named executive officers subject to the vote is disclosed in the “Executive Compensation” section, including the compensation tables and the related narrative disclosure, contained in this proxy statement. As discussed in those disclosures, the Company believes that neitherits compensation policies and decisions are focused onpay-for-performance principles and strongly aligned with our stockholders’ interests.

Accordingly, the Board of Directors nor any individual director may be removed without cause, and that any individual director or directors may be removed with cause byis asking the affirmative votestockholders to indicate their support for the compensation of the holders of at least 66 ²⁄₃% of the voting power of all then-outstanding shares of capital stock of the Company entitled to vote generally at an election of directors, voting togetherCompany’s named executive officers as a single class.

On December 21, 2015, the Delaware Chancery Court issued an opiniondescribed inIn re VAALCO Energy, Inc. Stockholder Litigation, Consol. C.A. No. 11775-VCL, invalidating as a matter of law provisions of the certificate of incorporation and bylaws of VAALCO Energy, Inc., a Delaware corporation that permitted the removal of VAALCO’s directors by its stockholders only for cause. The Chancery Court held that, in the absence of a classified board of cumulative voting, VAALCO’s “only for-cause” director removal provisions conflict with Section 141(k) of the Delaware General Corporation Law and are therefore invalid.

Section C of Article V of the Certificate of Incorporation contains a similar “only for-cause” director removal provision, and we do not have a classified board of directors or cumulative voting. As such, and in light of theVAALCO decision, the Board of Directors is requesting stockholder approval of the amendment and restatement of the Certificate of Incorporation (the “Charter Amendment”) to provide that any of our directors or our entire Board of Directors may be removed, with or without cause, by the holders of a majority of the shares then entitled to vote at an election of directors. The Charter Amendment is attached to this proxy statement by casting anon-binding advisory vote “FOR” the following resolution:

“RESOLVED, that the compensation paid to the Company’s named executive officers, as Appendix A.disclosed pursuant to Item 402 of RegulationS-K, including the compensation tables and narrative discussion is hereby APPROVED.”

IfBecause the Charter Amendmentvote is adopted by our stockholders,advisory, it will become effective upon the filing thereof with the Secretary of State of the State of Delaware. If the Charter Amendment is not approved by our stockholders, Section C of Article V of the Certificate of Incorporation will continue to be in conflict with Section 141(k) of the Delaware General Corporation Law.

Section 20 of our Amended and Restated Bylaws (the “Bylaws”) also contains a similar “only for-cause” director removal provision. On March 22, 2016,binding on the Board of Directors approved, subject to stockholder approval ofor the Charter Amendment,Company. Nevertheless, the amendment and restatement of the Bylaws in order to provide that, consistent with Section 141(k) of the Delaware General Corporation Law, any of our directors or our entire Board of Directors may be removed, with or without cause,views expressed by the holdersstockholders, whether through this vote or otherwise, are important to management and the Board and, accordingly, the Board and the Compensation Committee intend to consider the results of a majority of our shares of common stock then entitled tothis vote at an election of directors. No stockholder approval is being requested nor is required with respect to such amendment and restatement ofin making determinations in the Bylaws.future regarding executive compensation arrangements.

Vote Required

Approval of this Proposalproposal requires the affirmative vote of at least 66 ²⁄₃% of the shares of our common stock that are outstanding on the record date for the annual meeting. Abstentions and broker non-votes will be counted toward the tabulation of votes cast on the proposal and will have the same effect as “Against” votes.

Our Board of Directors believes that approval of this Proposal is advisable and in the best interests of our stockholders.

THE BOARDOF DIRECTORS RECOMMENDS

A VOTEFOR PROPOSAL 2

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PROPOSAL 3

RATIFICATIONOF SELECTIONOF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

The Audit Committee has selected Ernst & Young LLP as the Company’s independent registered public accounting firm for the fiscal year ending December 31, 2016 and has further directed that management submit the selection of independent registered public accounting firm for ratification by the stockholders at the annual meeting. Ernst & Young has audited the Company’s financial statements since its incorporation in 2009. Representatives of Ernst & Young are expected to be present at the annual meeting. They will have an opportunity to make a statement if they so desire and will be available to respond to appropriate questions.

Neither the Company’s Bylaws nor other governing documents or law require stockholder ratification of the selection of Ernst & Young as the Company’s independent registered public accounting firm. However, the Audit Committee is submitting the selection of Ernst & Young to the stockholders for ratification as a matter of good corporate practice. If the stockholders fail to ratify the selection, the Audit Committee will reconsider whether or not to retain that firm. Even if the selection is ratified, the Audit Committee in its discretion may direct the appointment of different independent auditors at any time during the year if they determine that such a change would be in the best interests of the Company and its stockholders.

The affirmative vote of the holders of a majority of the shares present in person or represented by proxy and entitled to vote on this matter at the annual meetingmeeting. Abstentions andbroker non-votes will be required to ratify the selection of Ernst & Young. Abstentions will be counted toward the tabulation of votes on proposals presented to the stockholdersa quorum for Proposal 2, and abstentions will have the same effect as negative“Against” votes. Broker non-votes (if any) are counted towards a quorum, but are not counted for any purpose in determining whether this matter has been approved.

PRINCIPAL ACCOUNTANT FEESAND SERVICES

The following table represents aggregate fees billed to the Company for the fiscal years ended December 31, 2015 and December 31, 2014, by Ernst & Young LLP, the Company’s principal accountant. All fees described below were pre-approved by the Audit Committee.

All fees described above were pre-approved by the Audit Committee.

In connection with the audit of each of the 2015 and 2014 financial statements, the Company entered into an engagement agreement with Ernst & Young which sets forth the terms by which Ernst & Young will perform audit services for the Company. Such agreements are subject to alternative dispute resolution procedures.

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During the fiscal years ended December 31, 2015 and December 31, 2014, none of the total hours expended on the Company’s financial audit by Ernst & Young were provided by persons other than Ernst & Young full-time permanent employees.

PRE -APPROVAL POLICIESAND PROCEDURES.

The Audit Committee must pre-approve the audit and non-audit services rendered by the Company’s independent registered public accounting firm.

THE BOARDOF DIRECTORS RECOMMENDS

A VOTEFORFOR PROPOSAL 32

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EXECUTIVE OFFICERS

The following table sets forth our current executive officers, their ages, and the positions held by each such person with the Company:

Dr. Grint’s biographical information is set forth above under Proposal 1.

Joseph “Jay” Hagan has served as our Chief Operating Officer, principal financial officer and principal accounting officer since January 2016. From June 2011 through December 2015, Mr. Hagan served as the Executive Vice President, Chief Financial Officer and Chief Business Officer of Orexigen Therapeutics, Inc. From May 2009 to June 2011, Mr. Hagan served as Orexigen’s Senior Vice President, Corporate Development, Strategy and Communications. From September 1998 to April 2008, Mr. Hagan served as Managing Director of Amgen Ventures. Prior to starting the Amgen Ventures Fund, Mr. Hagan served as Head of corporate development for Amgen Inc. Before joining Amgen, Mr. Hagan spent five years in the bioengineering labs at Genzyme and Advanced Tissue Sciences. Mr. Hagan has served on the board of directors of Zosano Pharma, a publicly traded biotechnology company, since May 2015. He received an M.B.A. from Northeastern University and a B.S. in Physiology and Neuroscience from the University of California, San Diego.

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SECURITY OWNERSHIPOF CERTAIN BENEFICIAL OWNERSAND MANAGEMENT

The following table sets forth certain information regarding the ownership of the Company’s common stock as of March 31, 2016 by: (i) each of our directors; (ii) each of our Named Executive Officers as defined below under the heading “Executive Compensation”; (iii) each person known by us to beneficially own more than 5% of our common stock and (iv) all of our current executive officers and directors as a group.

Beneficial ownership is determined in accordance with the rules of the SEC and includes voting and investment power with respect to the securities. This table is based upon information supplied by officers, directors and principal stockholders and Schedules 13D and 13G filed with the SEC. Except as indicated by footnote, and subject to applicable community property laws, we believe the persons named in the table have sole voting and investment power with respect to all shares of common stock shown as beneficially owned by them.

Percentage of beneficial ownership is based on 52,774,550 shares of common stock outstanding as of March 31, 2016. The number of shares of common stock used to calculate the percentage ownership of each listed person includes the shares of common stock underlying options held by such persons that are exercisable within 60 days following March 31, 2016. Unless otherwise indicated, the address for the following stockholders is c/o Regulus Therapeutics Inc., 3545 John Hopkins Court, Suite 210, San Diego, CA 92121.

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EXECUTIVEXECUTION COMPENSATION

This “Executive Compensation” section describesThe Company is a “smaller reporting company” under Item 10 ofRegulation S-K promulgated under the compensation decisions forExchange Act and the following compensation disclosure is intended to comply with the requirements applicable to smaller reporting companies. Although the rules allow the Company to provide less detail about its executive compensation program, the Compensation Committee is committed to providing the information necessary to help stockholders understand its executive compensation-related decisions. Accordingly, this section includes supplemental narratives that describe the 2019 executive compensation program for our Named Executive Officers.

Named Executive Officers. The following individuals who are our “Named Executive Officers” or “NEOs” for the year ended December 31, 2015:2019:

Dr. Grint was our only executive officer serving as of December 31, 2015. This section includes certain compensation information for Mr. Hagan, who commenced employment as our Chief Operating Officer in January 2016, to the extent such information may be helpful to an understanding of our executive compensation program.

SUMMARY COMPENSATION TABLESummary Compensation Table

The following table shows, for the fiscal years ended December 31, 20152019 and December 31, 2014,2018, compensation awarded to, paid to, or earned by, the Named Executive Officers.

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Narrative Disclosure to Summary Compensation Table

The three principal components of our executive compensation program for our Named Executive Officers in 2019 were base salary, annual performance-based bonus opportunity and equity compensation. We do not have any formal policies for allocating compensation among salary, performance bonus awards and equity grants, short-term and long-term compensation or among cash andnon-cash compensation. Instead, the Compensation Committee uses its judgment to establish a total compensation program for each named executive officer that is a mix of current, short-term and long-term incentive compensation, and cash andnon-cash compensation, that it believes appropriate to achieve the goals of our executive compensation program and our corporate objectives. In line with our pay for performance philosophy, we structured a significant portion of our Named Executive Officers’ 2019 compensation to be variable, at risk and tied directly to our measurable performance in the form of performance-based bonuses and equity incentives.

Base Salary

In December 2018, the Compensation Committee reviewed the base salaries for our then-current Named Executive Officers, the market data from Radford, our 3% Company-wide corporate merit increase target for base salaries, the scope of each executive’s responsibilities for 2019, each executive’s prior experience and internal pay equity in order to determine 2019 base salaries of our NEOs. In addition, in January 2019 in connection with Mr. Aker’s promotion to the position of SVP and General Counsel, Mr. Aker’s base salary was adjusted commensurate with his new title.

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The Named Executive Officers’ 2019 annual base salaries (effective January 1, 2019 for Mr. Hagan and Mr. Chevallard) and increases from 2018 annual base salaries approved by the Compensation Committee were as follows:

Annual Base Salary

The compensation of our Named Executive Officers is generally determined and approved by our Compensation Committee, who recommends its decisions to our Board of Directors. Our Board of Directors, without members of management present, ultimately ratifies and approves all compensation decisions. On December 2, 2014, our Board of Directors, upon the recommendation of our Compensation Committee, approved the following 2015 annual base salaries for our Named Executive Officers, which became effective on January 1, 2015, with the exception of Dr. Grint whose base salary became effective upon his elevation to President and Chief Executive Officer on June 1, 2015:

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On February 4, 2016, our Board of Directors, upon recommendation from the Compensation Committee approved the 2016 annual base salary for Dr. Grint, in the amount of $515,000, which was effective as of January 1, 2016. Our Board of Directors, upon the recommendation of our Compensation Committee, approved a 2016 annual base salary for Mr. Hagan of $415,000 effective upon Mr. Hagan’s commencement of employment on January 4, 2016.

Annual Performance-Based Bonus Opportunity

In addition to base salaries, our Named Executive Officers are eligible to receive annual performance-based cash bonuses, which are designed to provide appropriate incentives to our executives to achieve defined annual corporate goals and to reward our executives for individual achievement towards these goals.

The annual performance-based bonus each Named Executive Officer is eligible to receive is based on (1) the individual’s target bonus, as a percentage of base salary, (2) a Company-based performance factor (“CPF”), and (3) an individual performance factor (“IPF”). The actual performance-based bonus paid, if any, is calculated by taking into consideration the executive officer’s annual base salary, target bonus percentage, percentage attainment of the CPF and percentage attainment of the IPF. There is no designated proportion ofExcept for the Chief Executive Officer whose entire annual bonus attributed todepends upon the CPF, and the IPF and there20% of each other NEO’s annual bonus is no maximum bonus percentage or amount established for the Named Executive Officer and, as a result, the bonus amounts vary from year to year based on corporate and individual performance.also dependent upon such individual’s IPF. At the end of the year, our Compensation Committee approves the extent to which we achieved the CPF.CPF based on achievement of the corporate goals. The extent to which each individual Named Executive Officer achieves his or her IPF is determined based on our Chief Executive Officer’s and management’s review and recommendation to our Compensation Committee, except our Chief Executive Officer and our other Named Executive Officers do not make recommendations with respect to their own achievement, and our Compensation Committee makes the final decisions with respect to each IPF. Additionally, our Compensation Committee has the discretion to determine the weighting of each of the goals that comprise the CPF and IPF. Our Compensation Committee may award a bonus in an amount above or below the amount resulting from the calculation described above, based on other factors that our Compensation Committee determines, in its sole discretion, are material to our corporate performance and provide appropriate incentives to our executives, for example based on events or circumstances that arise after the original CPF and IPF goals are set. Our Compensation Committee did not exercise thisany such discretion in awarding the bonuses in 2015.2019.

Pursuant to their employment agreements, eachEach Named Executive Officer had aOfficer’s target bonus for 20152019, represented as a percentage of base salary, or a target bonus percentage, was 50% of base salary, with the exception of Mr. Hagan’s target bonus percentage, which is subject to modification from time to time inwas 60% of base salary.

The Compensation Committee determined the discretiontarget bonuses of each of our Board of Directors. Our NamedNEOs other than our Chief Executive Officers’ target bonus percentages for 2015 were as follows:Officer should be consistent to promote internal equity and reinforce teamwork across our leadership team.

The CPF and IPF goals are determined by our Compensation Committee and communicated to our Named Executive Officers each year, prior to or shortly following the beginning of the year to which they relate. The CPF is composed of several goals that relate to our annual corporate goals and various business accomplishments which vary from time to time depending on our overall strategic objectives, but relate generally to achievement of discovery, clinical, regulatory and manufacturing milestones for clinical development candidates, financial factors such as raising or preserving capital and performance against our operating budget and business

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development goals related tomicroRNA therapeutics.objectives. The IPF is composed of factors that relate to each Named Executive Officer’s ability to drive his or her own performance and the performance of his or her direct employee reports towards reaching our corporate goals. The proportional emphasis placed on each goal within the CPF and IPF may vary from time to time depending on our overall strategic objectives and our Compensation Committee’s subjective determination of which goals have more impact on our performance.

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For 2015,2019, the CPF overall goals related to the conservation of our cash while continuing to advance our most promising programs. The specific CPF goals were as follows:

During 2015, we achieved our key goals under the Clinical Map Initiative to advance our clinical development of RG-101 and RG012, further advanced ourmicroRNA pipeline, concluded the year with over $100 million in cash and succeeded in limiting our turnover. We also made significant achievements in the development of new initiatives during 2015, including our filing of multiple regulatory documents to initiate clinical trials in RG-101 and RG-012, the establishment of a global supply chain for RG-101, commencement of a collaboration with GSK to investigate RG-101 in combination with a GSK compound, and entry into a lease agreement for new premises which will allow the Company’s future growth. In February 2016,December 2019, after careful review, our Board of Directors, upon the recommendation of our Compensation Committee, approved aconcluded that we had achieved 85% of our CPF achievement of 100% which our Board believed was appropriategoals, based on the following:

The IPF goals varied by individual and included individual performance contributions towards maintaining a leading position in micro RNA research, accelerating efforts in micro RNA therapeutic development, supporting our growth with additional capital, fostering a culture of value creation, attracting and retaining key talent and building good processes and policies. Our Chief Executive Officer did not have IPF goals as his bonus is entirely dependent on our CPF goals, because our Chief Executive Officer has a direct impact on, and responsibility for, our corporate performance.

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Based on Human Resources’our Chief Executive Officer’s recommendations with respect to each other Named Executive Officer, and our Compensation Committee’s deliberations with respect to each Named Executive Officer’s individual performance against the IPF, in February 2016 our Compensation Committee and Board of Directors approved a performance-based bonus in the amount of $250,000 for Dr. Grint, in recognition of his ability to lead and develop the organization towards progressing our clinical portfolio, exploring different possible combinations of RG-101 with other antivirals and exceeding our year-end cash projections. Our other Named Executive Officers did not receive performance-based bonuses due to their resignations.

For 2016, upon recommendation by the Compensation Committee, the Board of Directors approved a 2016 target bonus for Mr. Hagan of 40% of his annual base salary. Dr. Grint’s 2016 target bonus remains the same as his 2015 target bonus.

Long-Term Incentive Compensation

Our long-term, equity-based incentive awards are designed to align the interestseach of our Named Executive Officers as set forth in the table below based on a 85% CPF and IPF as indicated, weighted 80% and 20%, respectively, except for our other employees, non-employee directors and consultants with the interestsChief Executive Officer, whose bonus was weighted 100% on CPF goals:

Equity-Based Incentive Awards

Equity incentives are a key component of our stockholders. Because vesting isexecutive compensation program that the Compensation Committee believes motivate executive officers to achieve our business objectives by tying incentives to the appreciation of our common stock and, in the case of performance-vesting awards, measurable performance goals. In the past, we have primarily granted equity awards in the form of stock options that vest based on achievement of specific Company performance goals and/or continued service and, more recently, RSU stock awards that vest based on continued service, our equity-based incentives also encourage the retentionservice.

Stock Awards. In 2019, each of our Named Executive Officers throughreceived time-vesting RSUs and performance-based stock options in the vesting periodamounts listed below. In addition, after approval of the awards.

We use stock options as the primary incentive for long-term compensation to our Named Executive Officers because they are able to profit from stock options only if our stock price increases relative to the stock option’s exercise price. We generally provide initial grants in connection with the commencement of employment of our Named Executive Officers and annual retention grants at or shortly following the end of each year.

Prior to 2012, we granted all stock options pursuant to our 20092019 Equity Incentive Plan (the “2009 Plan”),by our stockholders in August 2019, the terms of which are described below under “Equity Compensation PlansCommittee determined that our employees, including our NEOs, did not hold sufficient stock awards to retain and Other Benefit Plans—2009 Equity Incentive Plan.” All options granted under the 2009 Plan were granted with an exercise price per share equal to no less than the fair market valueincentivize our employees. Consequently each of our commonemployees, including our NEOs, received a time-based stock on the date ofoption grant of each award. Since October 2012,

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allThe performance-vesting stock options have been granted pursuantvest and can be earned only if performance goals key to our 2012 Equity Incentive Plan (the “2012 Plan”) or the 2015 Inducement Plan (“2015 Inducement Plan”)future success are achieved (in addition to continued service), the terms of which are described below under “Equity Compensation Plans and Other Benefits Plans—2012 Equity Incentive Plan” and “Equity Compensation Plans and Other Benefits Plans—2015 Inducement Plan” respectively. All options granted under the 2012 Plan or the 2015 Inducement Plan are granted with an exercise price per share equal to the fair market value of our common stock on the date of grant.

Most of our stock option grants vest over a four-year period and may be granted with an early exercise feature allowing the holder to exercise and receive unvested shares of our stock, so that the employee may exercise and have a greater opportunity for gains on the shares to be taxed at long-term capital gains rates rather than ordinary income rates. Beginning in late 2013, our Compensation Committee also decided to grant options that vest based on our achievement of specific Company goals, which we believethereby further aligns our Named Executive Officers’ interests with our Company goals and the interests of our stockholders. In addition, our Compensation Committee has approved certain grants of options to our Named Executive Officers containing accelerated vesting provisions upon an involuntary termination (both termination without cause and resignation for good reason) as well as upon certain material change in control transactions. Our Compensation Committee believes these accelerated vesting provisions reflect current market practices, based on the collective knowledge and experiences of our Compensation Committee members (and without reference to specific peer group data), and allow us to attract and retain highly qualified executive officers. In addition, we believe these accelerated vesting provisions will allowincentivizing our Named Executive Officers to focus on closing a transaction that may beachieve these goals to drive increases in the best interest of our stockholders even though the transaction may otherwise result in a termination of their employment and, absent such accelerated vesting, a forfeiture of their unvested equity awards. Additional information regarding accelerated vesting provisionslong-term value for our Named Executive Officers is discussed below under “Employment Agreements with Executive Officers.”

On January 5, 2015, our Compensation Committee granted performance-based stock option awards to purchase 72,625 shares to Dr. Grint, 152,267 shares of common stock to Dr. Xanthopoulos, 62,631 shares to Dr. Gibson, and 46,154 shares to Mr. Szekeres, each of which options were granted with an exercise price of $16.24 per share. The terms of the options specify that vesting commences only upon achievement, by June 30, 2016, of a future corporate goal that relates to specified outcomes concerning our current and future clinical development plans. The extent to which we achieve each goal will be determined by our Compensation Committee and upon such determination, if the goal is achieved, 50% of the shares attributable to such goal will vest and the remaining shares attributable to the goal shall vest in equal installments on a monthly basis thereafter such that all shares shall be vested within two years of the achievement of the goal, provided that the option holder continues to provide services to us through such dates. Each of Dr. Xanthopoulos, Dr. Gibson and Mr. Szekeres forfeited the foregoing options upon their resignations in 2015.

On June 25, 2015, in connection with his appointment as President and CEO, we granted Dr. Grint an option to purchase 500,000 shares of common stock with an exercise price of $10.22 per share. Twenty-five percent of the total number of shares subject to the option vested on June 24, 2016, and the remainder will vest in equal monthly installments thereafter for the following three years, provided that Dr. Grint continues to provide services to us through such dates.

On February 4, 2016, we awarded an annual retention grant to Dr. Grint in the form of an option to purchase 265,000 shares of common stock which option has an exercise price of $6.35 per share. Twenty-five percent of the total number of shares subject to the option vests on January 1, 2017, and the remainder will vest in equal monthly installments thereafter over the following three years, provided that Dr. Grint continues to provide services to us through such dates. In addition, on February 4, 2016, we granted Dr. Grint a performance-based stock option to purchase 130,000 shares of common stock which option also has an exercise price of $6.35 per share. The option will commence vesting only upon achievement of a future corporate goal that relates to specified outcomes concerning our future clinical development plans and must be achieved by the end of 2016.

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On January 4, 2016, in connection with his commencement of employment as our Chief Operating Officer, we granted Mr. Hagan a stock option exercisable for up to 420,000 shares of common stock, 25% of which shares will vest one year after the grant date and the balance of which will vest in equal monthly installments over the following three years, subject to Mr. Hagan’s continuous service with us. On January 4, 2016 we also granted Mr. Hagan a performance-based stock option exercisable for up to 122,631 shares of common stock. The stock option will vest upon the achievement of specified performance-based development milestones. Fifty percent of the shares subject to any particular performance-based milestone will vest upon the determination by the Board or Compensation Committee that such milestone has been achieved, and the balance of the shares subject to such milestone will vest in equal monthly installments over the following two years, subject to Mr. Hagan’s continuous service with us.stockholders.

Perquisites, Health, Welfare and Retirement BenefitsOther Compensation

Our Named Executive Officers are eligible to participate in all of our employee benefit plans, including our medical, dental, vision, group life and disability insurance plans, in each case on the same basis as other employees. We provide 401(k) matching contributions as discussed in the section below entitled “Equity Compensation Plans and Other Benefit Plans—401(k) Plan.”

We do not provide perquisites or personal benefits to our Named Executive Officers. We do, however,also pay the premiums for term life insurance and long-term disability for all of our employees, including our Named Executive Officers. None of our Named Executive Officers participate in or have account balances in qualified ornon-qualified defined benefit plans sponsored by us.

We generally do not provide perquisites or personal benefits to our Named Executive Officers, although we may from time to time provide signing bonuses or other reasonable benefits as our Compensation Committee Interlocks and Insider Participationdetermines appropriate.

As indicated above,All of our full-time employees in the Compensation Committee currently consists of Dr. Baltimore and Dr. Rastetter. No memberUnited States, including our Named Executive Officers, are eligible to participate in our 401(k) plan, which is a retirement savings defined contribution plan established in accordance with Section 401(a) of the Compensation Committee has ever been an officer or employeeCode. Pursuant to our 401(k) plan, employees may elect to defer their eligible compensation into the plan on apre-tax basis, up to the statutorily prescribed annual limit of ours. None of our executive officers currently serves, or has served during the last completed fiscal year, on the compensation committee or board of directors of any other entity that has one or more executive officers serving as a member of our Board of Directors or Compensation Committee.

Outstanding Equity Awards at Fiscal Year-End.

The following table shows certain information regarding outstanding equity awards as of December 31, 2015 for the Named Executive Officers.

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During 2015,(additional salary deferrals not to exceed $6,000 are available to those employees 50 years of age or older) and to have the amount of this reduction contributed to our 401(k) plan. In 2019, we made modifications under ASC 718provided a $0.50 match for every dollar our employees elect to outstanding equity awards of Dr. Xanthopoulos and Dr. Gibson in connection with eachdefer up to 6% of their resignations.eligible compensation. In general, eligible compensation for purposes of the 401(k) plan includes an employee’s wages, salaries, fees for professional services and other amounts received for personal services actually rendered in the course of employment with us to the extent the amounts are includible in gross income, and subject to certain adjustments and exclusions required under the Code. The modifications are described above under “Summary Compensation Table” and below under “Employment Agreements with Named Executive Officers.”401(k) plan currently does not offer the ability to invest in our securities.

Employment Agreements with Named Executive Officers

Employment Agreements.We entered into employment agreements with each of our Named Executive Officers. The agreements provide for at will employment and for certain base salary, target bonus and severance payments to our Named Executive Officers.

Employment Agreement with Dr. Grint.Mr.In September 2014, we entered into an amended and restated employment agreement with Dr. Grint, which replaced and superseded his previous agreement entered into in June 2014. Pursuant to his employment agreement, Dr. Grint is entitled to an initial annual base salary of $360,500 (increased most recently to $500,000) and in 2015 was eligible to receive an annual performance bonus

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based on a target amount of 35% (increased most recently to 50%) of his annual base salary. Dr. Grint’s base salary and target bonus percentage are subject to modification from time to time in the discretion of our Board of Directors or any authorized committee thereof.

Under the terms of his employment agreement, if we terminate Dr. Grint’s employment without cause (other than due to his death or complete disability) or if Dr. Grint resigns for good reason at any time other than during the period beginning one month before and ending 12 months following a change in control, we are obligated to pay Dr. Grint, subject to receiving an effective release and waiver of claims from him, (1) a lump sum severance payment equal to 12 months of base salary in effect at the time of termination (ignoring any decrease that forms the basis for a resignation for good reason), (2) a lump sum cash amount equal to 229.56% multiplied by the total cost of the projected premiums for group medical, dental and vision insurance for a period of 12 months and (3) vesting acceleration of all outstanding time-based options or other equity incentive awards held by Dr. Grint as of such termination.

If we terminate Dr. Grint’s employment without cause (other than due to his death or complete disability) or if Dr. Grint resigns for good reason, in each case during the period beginning one month before and ending 12 months following a change in control, in lieu of the severance payment described above, we are obligated to pay Dr. Grint, subject to receiving an effective release and waiver of claims from him (1) a lump sum severance payment equal to 12 months of his base salary in effect at the time of termination (ignoring any decrease that forms the basis for a resignation for good reason), (2) a lump sum payment equal to the target amount of Dr. Grint’s annual performance bonus payable for the year of termination, (3) a lump sum cash amount equal to 229.56% multiplied by the total cost of the projected premiums for group medical, dental and vision insurance for a period of 12 months and (4) vesting acceleration of all outstanding time-based options or other equity incentive awards held by Dr. Grint as of such termination.

Employment Agreement with Dr. Xanthopoulos.In September 2014, we entered into an amended and restated employment agreement with Dr. Xanthopoulos, which replaced and superseded his previous employment agreement entered into in June 2012. Pursuant to his employment agreement, Dr. Xanthopoulos was entitled to receive an initial annual base salary (increased most recently to $637,158) and in 2015 was eligible to receive an annual performance bonus based on a target amount of 60% of his annual base salary. Dr. Xanthopoulos’s base salary and target bonus percentage were subject to modification from time to time in the discretion of our Board of Directors or any authorized committee thereof.

In June of 2015, Dr. Xanthopoulos resigned from the Company. In connection with his resignation, and in exchange for our receipt of an effective release and waiver of claims from Dr. Xanthopoulos, Dr. Xanthopoulos received (1) a severance payment equal to 18 months of his base salary in effect at the time of his resignation, (2) a lump sum cash amount equal to 229.56% multiplied by the total cost of the projected premiums for group medical, dental and vision insurance for a period of 18 months and (3) vesting acceleration of all outstanding options held by Dr. Xanthopoulos that were subject to time-based vesting as of the time of his resignation. In addition, the post-termination exercise period of all outstanding options held by Dr. Xanthopoulos was extended to 180 days following the date of his resignation. Half of the total amount of the severance payment described in (1) above was paid in a lump sum payment and half of the total amount of the severance payment will be paid in equal installments over a 12-month period following Dr. Xanthopoulos’ resignation.

Employment Agreement with Dr. Gibson.In September 2014, we entered into an amended and restated employment agreement with Dr. Gibson, which replaced and superseded his previous employment agreement entered into in June 2012. Pursuant to his employment agreement, Dr. Gibson was entitled to an initial annual base salary of $360,500 (increased most recently to $371,676) and in 2015 was eligible to receive an annual performance bonus based on a target amount of 35% of his annual base salary. Dr. Gibson’s base salary and target bonus percentage were subject to modification from time to time in the discretion of our Board of Directors or any authorized committee thereof.

In June of 2015, Dr. Gibson resigned from the Company. In connection with his resignation, and in exchange for our receipt of an effective release and waiver of claims from Dr. Gibson, Dr. Gibson received (1) a

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lump-sum severance payment equal to 12 months of his base salary in effect at the time of his resignation, (2) a lump sum cash amount equal to 229.56% multiplied by the total cost of the projected premiums for group medical, dental and vision insurance for a period of 12 months and (3) vesting acceleration of all outstanding options held by Dr. Gibson that were subject to time-based vesting as of the time of his resignation. In addition, the post-termination exercise period of all outstanding options held by Dr. Gibson was extended to 180 days following the date of his resignation.

Employment Agreement with Mr. Szekeres.In September 2014, we entered into an amended and restated employment agreement with Mr. Szekeres, which replaced and superseded his previous agreement entered into in February 2014. Pursuant to his employment agreement, Mr. Szekeres was entitled to an initial annual base salary of $295,000 (increased most recently to $303,267) and in 2015 was eligible to receive an annual performance bonus based on a target amount of 35% of his annual base salary. Mr. Szekeres’s base salary and target bonus percentage were subject to modification from time to time in the discretion of our Board of Directors or any authorized committee thereof.

In December of 2015, Mr. Szekeres resigned from the Company. In connection with his resignation, and in exchange for our receipt of an effective release and waiver of claims from Mr. Szekeres, Mr. Szekeres received (1) a lump-sum severance payment equal to 12 months of his base salary in effect at the time of his resignation, (2) a lump sum cash amount equal to 229.56% multiplied by the total cost of the projected premiums for group medical, dental and vision insurance for a period of 12 months and (3) vesting acceleration of all outstanding options held by Mr. Szekeres that were subject to time-based vesting as of the time of his resignation.

Employment Agreement with Mr. Hagan.In December 2015, we entered into an employment agreement with Mr. Hagan, with an effective date of January 1, 2016. Pursuant to his employment agreement, Mr. Hagan is entitled to receive an annual base salary of $415,000 and is eligible to receive an annual performance bonus, with a target bonus amount of 40% of his annual base salary. Mr. Hagan’s base salary and target bonus are subject to periodic review and adjustment from time to time in the discretion of our Board of Directors or the Compensation Committee.Committee and have been subsequently increased. In May 2017, Mr. Hagan was appointed as our President and Chief Executive Officer. At that time, his base salary was increased to $500,000 and his target bonus was increased to 50%. Additionally, Mr. Hagan’s employment agreement provides for the grant of stock option awards, which were made in January 2016. Pursuant to Mr. Hagan’s employment agreement, we agreedall outstanding stock options subject to payvesting based on Company performance that are held by Mr. Hagan immediately before a signing bonuschange in control shall become fully vested and exercisable as of $100,000, payableimmediately before, and contingent upon, the change in a lump sum uponcontrol, provided that Mr. Hagan remains employed by us as of such date. In 2019, Mr. Hagan’s commencement of employment with us. All or a portion of the signingbase salary was increased to $535,600 and his target bonus is repayable in the event Mr. Hagan is terminated for cause or if he voluntarily resigns without good reason within the first three yearswas increased to 60% of his employment.annual base salary.

If we terminate Mr. Hagan’s employment without cause (other than due to his death or complete disability) or if Mr. Hagan resigns for good reason at any time other than during the period beginning one month before and ending 12 months following a change in control, weMr. Hagan will be obligated to pay Mr. Hagan,receive, subject to receiving an effective release and waiver of claims from him, (1) a lump sum severance payment equal to 12 months of his then-current base salary in effect at the time of such termination or resignation (disregarding any decrease that forms the basis for a resignation for good reason), (2) a lump sum cash amount equal to 229.56% multiplied by the total cost of the projected premiums for group medical, dental and vision insurance for a period of 12 months and (3) vesting acceleration of all outstanding options and other equity incentive awards subject to time-based vesting held by Mr. Hagan as of such termination or resignation.

If we terminate Mr. Hagan’s employment without cause (other than due to his death or complete disability) or if Mr. Hagan resigns for good reason, in each case during the period beginning one month before and ending 12 months following a change in control, in addition to the severance payment described above, we will also be obligated to pay Mr. Hagan, subject to receiving an effective release and waiver of claims from him, a lump sum payment equal to the target amount of Mr. Hagan’s annual performance bonus for the year of termination or resignation.

Employment Agreement with Mr. Aker. In July 2018, we entered into an amended and restated employment agreement with Mr. Aker. Pursuant to his amended and restated employment agreement, on January 4, 2016, we granted Mr. HaganAker is entitled to receive an optionannual base salary of $246,376 and is eligible to purchase up to 420,000 sharesreceive an annual performance bonus, with a target bonus amount of common stock, 25%50% of which shares will vest one year after the grant datehis annual base salary. Mr. Aker’s base salary and the balance of which will vest in equal monthly installments over the following three years,target bonus are subject to Mr. Hagan’s continuous service with us. Pursuantperiodic review and adjustment from time to his employment agreement, on January 4, 2016 we also granted Mr. Hagan a performance-based stock option exercisable for up to 122,631 sharestime in the discretion of common stock. The stock

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option will vest upon the achievement of specified performance-based development milestones. Fifty percent of the shares subject to any particular performance-based milestone will vest upon the determination by our Board of Directors or the Compensation Committee that such milestoneand his base salary has been achieved,subsequently increased. Pursuant to Mr. Aker’s amended and restated employment agreement, all outstanding stock options subject to vesting based on Company performance that are

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held by Mr. Aker immediately before a change in control shall become fully vested and exercisable as of immediately before, and contingent upon, the balancechange in control, provided that Mr. Aker remains employed by us as of such date. In 2019, Mr. Aker’s base salary was increased to $290,000 and his target bonus remained at 50% of his annual base salary.

If we terminate Mr. Aker’s employment without cause (other than due to his death or complete disability) or if Mr. Aker resigns for good reason at any time other than during the period beginning one month before and ending 12 months following a change in control, Mr. Aker will receive, subject to receiving an effective release and waiver of claims from him, (1) a lump sum severance payment equal to 12 months of his then-current base salary (disregarding any decrease that forms the basis for a resignation for good reason), (2) a lump sum cash amount equal to 229.56% multiplied by the total cost of the sharesprojected premiums for group medical, dental and vision insurance for a period of 12 months and (3) vesting acceleration of all outstanding options and other equity incentive awards subject to time-based vesting held by Mr. Aker as of such milestonetermination or resignation.

If we terminate Mr. Aker’s employment without cause (other than due to his death or complete disability) or if Mr. Aker resigns for good reason, in each case during the period beginning one month before and ending 12 months following a change in control, in addition to the severance payment described above, we will vest in equal monthly installments over the following two years,also be obligated to pay Mr. Aker, subject to receiving an effective release and waiver of claims from him, a lump sum payment equal to the target amount of Mr. Hagan’s continuous serviceAker’s annual performance bonus for the year of termination or resignation.

Employment Agreement with us.Ms. Calsada. In August 2019, we entered into an employment agreement with Ms. Calsada with an effective date of August 30, 2019 upon her commencement of employment as our Chief Financial Officer. Pursuant to her employment agreement, Ms. Calsada is entitled to receive an annual base salary of $310,000 and is eligible to receive an annual performance bonus, with a target bonus amount of 50% of her annual base salary. Ms. Calsada’s base salary and target bonus are subject to periodic review and adjustment from time to time in the discretion of our Board of Directors or the Compensation Committee and her base salary has been subsequently increased. At the time she commenced her employment with us, Ms. Calsada also received an initial stock option grant of 100,000 shares. Pursuant to Ms. Calsada’s employment agreement, all outstanding stock options subject to vesting based on Company performance that are held by Ms. Calsada immediately before a change in control shall become fully vested and exercisable as of immediately before, and contingent upon, the change in control, provided that Ms. Calsada remains employed by us as of such date.

If we terminate Ms. Calsada’s employment without cause (other than due to her death or complete disability) or if Ms. Calsada resigns for good reason at any time other than during the period beginning one month before and ending 12 months following a change in control, Ms. Calsada will receive, subject to receiving an effective release and waiver of claims from her, (1) a lump sum severance payment equal to 12 months of her then-current base salary (disregarding any decrease that forms the basis for a resignation for good reason), (2) a lump sum cash amount equal to 229.56% multiplied by the total cost of the projected premiums for group medical, dental and vision insurance for a period of 12 months and (3) vesting acceleration of all outstanding options and other equity incentive awards subject to time-based vesting held by Ms. Calsada as of such termination or resignation.

If we terminate Ms. Calsada’s employment without cause (other than due to her death or complete disability) or if Ms. Calsada resigns for good reason, in each case during the period beginning one month before and ending 12 months following a change in control, in addition to the severance payment described above, we will also be obligated to pay Ms. Calsada, subject to receiving an effective release and waiver of claims from her, a lump sum payment equal to the target amount of Ms. Calsada’s annual performance bonus for the year of termination or resignation.

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Employment Agreement with Mr. Chevallard.

Mr. Chevallard voluntary terminated his employment with us effective July 26, 2019. Prior to his termination, if we had terminated Mr. Chevallard’s employment without cause (other than due to his death or complete disability) or if Mr. Chevallard resigned for good reason at any time other than during the period beginning one month before and ending 12 months following a change in control, Mr. Chevallard was eligible to receive, subject to receiving an effective release and waiver of claims from him, (1) a lump sum severance payment equal to 12 months of his then-current base salary (disregarding any decrease that forms the basis for a resignation for good reason), (2) a lump sum cash amount equal to 229.56% multiplied by the total cost of the projected premiums for group medical, dental and vision insurance for a period of 12 months and (3) vesting acceleration of all outstanding options and other equity incentive awards subject to time-based vesting held by Mr. Chevallard as of such termination or resignation.

If we terminated Mr. Chevallard’s employment without cause (other than due to his death or complete disability) or if Mr. Chevallard resigned for good reason, in each case during the period beginning one month before and ending 12 months following a change in control, in addition to the severance payment described above, we were also obligated to pay Mr. Chevallard, subject to receiving an effective release and waiver of claims from him, a lump sum payment equal to the target amount of Mr. Chevallard’s annual performance bonus for the year of termination or resignation. As a result of his voluntary termination, Mr. Chevallard did not receive any severance benefits and is no longer entitled to any severance benefits under his employment agreement.

Upon Mr. Chevallard’s resignation, effective July 26, 2019, the Company entered into a consulting agreement with Mr. Chevallard to assist with the transition of duties to our new Chief Financial Officer. Pursuant to the consulting agreement, Mr. Chevallard was paid $300.00 per hour for his services. The consulting agreement superseded all prior agreements between us and Mr. Chevallard. The term of the consulting agreement was through March 31, 2020 at which time Mr. Chevallard ceased providing services to the Company.

None of the Named Executive Officers’ or Mr. Hagan’s employment agreementagreements provide for the gross upgross-up of any excise taxes imposed by Section 4999 of the Code. If any of the payments under the employment agreements would constitute a “parachute payment” within the meaning of Section 280G of the Code, subject to the excise tax imposed by Section 4999 of the Code, the employment agreements provide for a best-after tax analysis with respect to such payments, under which the executive will receive whichever of the following two alternative forms of payment would result in the executive officer’s receipt, on anafter-tax basis, of the greater amount of the transaction payment notwithstanding that all or some portion of the transaction payment may be subject to the excise tax: (i) payment in full of the entire amount of the transaction payment, or (ii) payment of only a part of the transaction payment so that the executive receives the largest payment possible without the imposition of the excise tax.

For purposesChange in Control and Severance Benefits

Under the terms of the employment agreements other than duringwith each of our Named Executive Officers described above, either we or the period beginning one month before and ending 12 months followingexecutive may terminate the executive’s employment at any time. Each of our Named Executive Officers is eligible, under the terms of his or her respective employment agreement, to receive, in exchange for a release of claims, severance benefits upon the termination of employment either by us without cause or by the executive for good reason, with additional severance benefits provided in the event the termination is in connection with a change in control, “cause” generally means the executive officer’s: (i) commission of any felony or crime involving fraud, dishonesty or moral turpitude under the laws of the United States or any state thereof; (ii) attempted commission of, or participation in, a fraud or act of dishonesty against us; (iii) intentional, material violation of any contract or agreement between the executive officer and us or of any statutory duty owed to us; (iv) unauthorized use or disclosure of our confidential information or trade secrets; or (v) gross misconduct. During the period beginning one month before and ending 12 months following a change in control, “cause” generally means the executive officer’s: (I) conviction of any felony or any crime involving fraud, dishonesty or moral turpitude under the laws of the United States or any state thereof; (II) commission of an intentional act of fraud, embezzlement or theft by the executive officer in the course of the executive officer’s employment by us; (III) intentional, material violation of any contract or agreement between the executive officer and us (including the employment agreement) or of any statutory duty owed to us which is not remedied within 30 days’ written notice from us specifying such failure; (IV) intentional and unauthorized use or disclosure of our confidential information or trade secrets which is materially and demonstrably injurious to us; or (V) gross misconduct.

For purposes of the employment agreements, “good reason” means the occurrence of one or more of the following events (at a time other than within one month before or 12 months following a change in control), subject to the executive providing us with at least 90 days of his intent to terminate for such “good reason” and our failure to remedy the condition within a 30-day cure period (provided, any subsequent proposed voluntary resignation for “good reason” will not be curable): (i) our material breach of the executive officer’s employment agreement; (ii) a material reduction of the executive officer’s base salary; (ii) a material reduction of the executive officer’s authority, duties or responsibilities; or (iii) a relocation of the facility that is the executive officer’s principal place of business to a location that requires an increase in the executive officer’s one-way driving distance by more than 35 miles. Within one month before or 12 months following a change in control, “good reason” means the occurrence of one of the following without the executive officer’s express, written consent: (I) a significant reduction of the executive officer’s duties, position or responsibilities (including, without limitation, any negative change in reporting hierarchy involving the executive or the person to whom the executive directly reports, or the executive no longer being a Section 16 reporting officer immediately following the change in control), or the executive officer’s removal from such position and responsibilities; (II) our change to the timing associated with long-term incentive awards granted to the executive officer; (III) a reduction by us in the executive officer’s (A) base salary or target annual bonus as in effect immediately prior to such reduction, or (B) annual grant date fair value of any long-term incentive awards held by the executive officer relative to the highest fair value award granted to the executive during the three-year period prior to a change in control; (IV) a material reduction by us in the kind or aggregate level of employee benefits to which the executive officer is entitled immediately prior to such reduction with the result that the executive officer’s overall benefits package is

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significantly reduced; (V) the executive officer is requested to relocate (except for office relocations that would not increase the executive officer’s one way commute by more than 35 miles); or (VI) our failure to obtain the assumption of the employment agreement by the acquiror in the change in control transaction.

For purposes of the employment agreements, “change in control” generally means one or more of the following events (i) the acquisition of more than 50% of our combined voting power other than by Alnylam or Ionis (formerly Isis) (although this exception does not apply to Mr. Hagan’s employment agreement); (ii) a consummation of a merger, consolidation or similar transaction in which our stockholders cease to own outstanding voting securities representing more than 50% of the voting power of the parent or the surviving entity immediately following the merger; or (iii) a consummated sale, lease, exclusive license or other disposition of all or substantially all of our consolidated assets (other than to an entity of which more than 50% of the voting power is owned immediately following such disposition by our stockholders).

Compensation Recovery Policies

The Board of Directors and the Compensation Committee have not determined whether they would attempt to recover bonuses from our executive officers if the performance objectives that led to the bonus determination were to be restated, or found not to have been met to the extent originally believed by the Board of Directors or the Compensation Committee. However, as a public company subject to the provisions of Section 304 of the Sarbanes-Oxley Act of 2002, if we are required as a result of misconduct to restate our financial results due to our material noncompliance with any financial reporting requirements under the federal securities laws, our Chief Executive Officer and our principal financial officer may be legally required to reimburse us for any bonus or other incentive-based or equity-based compensation they receive.control. In addition, we will comply with the requirements of the Dodd-Frank Wall Street Reform and Consumer Protection Act and will adopt a compensation recovery policy once final regulations on the subject have been adopted.

Equity Compensation Plans and Other Benefits Plans

2009 Equity Incentive Plan.

Our Board of Directors adopted and our stockholders approved the 2009 Plan in January 2009 for eligible employees, directors and consultants. The terms of the stock option agreements, including vesting requirements, were determined by our Board of Directors, subject to the provisions of the 2009 Plan. Options granted under the 2009 Plan generally vest over four years and are exercisable after they have been granted and up to ten years from the date of grant. The exercise price of the incentive stock options must equal at least 100% of the fair market value of our common stock on the date of grant. Following our initial public offering in October 2012, no additional awards have been or will be granted under the 2009 Plan, and all awards granted under the 2009 Plan that are repurchased, forfeited, expire or are cancelled become available for grant under the 2012 Plan in accordance with its terms. However, all stock options granted under the 2009 Plan prior to our initial public offering continue to be governed by the terms of the 2009equity awards granted to our Named Executive Officers are subject to the terms of our equity plans and award agreements thereunder, which includes accelerated vesting provisions upon certain material change in control transactions. We do not provide any excise taxgross-ups onchange-in-control benefits.

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Outstanding Equity Awards at FiscalYear-End

The following table shows certain information regarding outstanding equity awards as of December 31, 2019 for the Named Executive Officers:

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Equity Compensation Plans.

From October 2012 until August 2019, all equity awards (other than inducement awards) were granted pursuant to our 2012 Equity Incentive Plan (the “2012 Plan”). Beginning in August 2019, all equity awards (other than inducement awards) will be granted pursuant to our 2019 Equity Incentive Plan (the “2019 Plan”). In addition, we may grant inducement awards to new employees under our 2015 Inducement Plan (“2015 Inducement Plan”). The terms of these plans are described below.

20122019 Equity Incentive Plan.

The 20122019 Plan, which became effective in connection with our initial public offering in October 2012,August 2019, provides for the grant of incentive stock options, or ISOs, within the meaning of Section 422 of the Code, nonstatutory stock options, or NSOs, stock appreciation rights, restricted stock awards, restricted stock unit awards, performance-based stock awards, and other forms of equity compensation, or collectively, stock awards. Additionally, the 20122019 Plan provides for the grant of performance cash awards. ISOs may be granted only to employees, subject to certain limitations. All other awards may be granted to employees, including officers, and tonon-employee directors and consultants.

Our Board of Directors, or a duly authorized committee thereof, has the authority to administer the 20122019 Plan. Our Board of Directors has delegated its authority to administer the 20122019 Plan to our Compensation

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Committee under the terms of our Compensation Committee’s charter. Our Board of Directors may also delegate certain authority to one or more of our officers. Our Board of Directors or its authorized committee is referred to herein as the plan administrator.

Initially, the aggregate number of shares of our common stock that may be issued pursuant to stock awards under the 2012 Plan was the sum of (i) 1,500,000 shares, plus (ii) the 731,781 shares reserved for issuance under our 2009 Plan at the time our 2012 Plan became effective, plus (iii) any shares subject to stock options or other stock awards granted under our 2009 Plan that would have otherwise returned to our 2009 Plan (such as upon the expiration or termination of a stock award prior to vesting). Additionally, the number of shares of our common stock reserved for issuance under our 2012 Plan automatically increases on January 1 of each calendar year, beginning on January 1, 2013 and continuing through and including January 1, 2022, by 4% of the total number of shares of our capital stock outstanding on December 31 of the preceding calendar year, or a lesser number of shares determined by our Board of Directors. The maximum number of shares that may be issued upon the exercise of ISOs under our 2012 Plan is 3,000,000 shares. As of December 31, 2015, there were 1,549,163 shares available for future grants under the 2012 Plan. On January 1, 2016, pursuant to the terms of the 2012 Plan, the number of shares available for issuance under the 2012 Plan automatically increased by 2,106,770 shares.

Stock options are generally granted with an exercise price equal to the fair market value of our common stock on the date of grant, vest at the rate specified by the plan administrator (often over a four-year period) and may have a term up to a maximum of 10 years. The exercise price for an ISO or NSO generally cannot be less than 100% of the fair market value of our common stock on the date of grant. Unless the terms of an optionee’s stock option agreement provides otherwise, if an optionee’s service relationship with us, or any of our affiliates, ceases for any reason other than disability, death or cause, the optionee may generally exercise any vested options for a period of three months following the cessation of service. The option term may be extended in the event that exercise of the option following such a termination of service is prohibited by applicable securities laws or our insider trading policy. If an optionee’s service relationship with us, or any of our affiliates, ceases due to disability or death, or an optionee dies within a certain period following cessation of service, the optionee or a beneficiary may generally exercise any vested options for a period of 12 months in the event of disability and 18 months in the event of death. In the event of a termination for cause, options generally terminate immediately upon the termination of the individual. In no event may an option be exercised beyond the expiration of its term.

UnlessRestricted stock units generally stop vesting upon the plan administrator providesholder’s termination of service with us and any unvested restricted stock units are forfeited, unless otherwise options generally are not transferable except by will,provided in an agreement with the laws of descent and distribution, or pursuant to a domestic relations order. An optionee may designate a beneficiary, however, who may exercise the option following the optionee’s death.holder.

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Corporate transactions. In the event of certain specified significant corporate transactions (as defined in the 2019 Plan), the plan administrator has the discretion to take any of the following actions with respect to stock awards:

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Under the 2012 Plan, a corporate transaction is generally the consummation of (i) a sale or other disposition of all or substantially all of our consolidated assets, (ii) a sale or other disposition of at least 90% of our outstanding securities, (iii) a merger, consolidation or similar transaction following which we are not the surviving corporation, or (iv) a merger, consolidation or similar transaction following which we are the surviving corporation but the shares of our common stock outstanding immediately prior to such transaction are converted or exchanged into other property by virtue of the transaction.

Change in control. The plan administrator may provide, in an individual award agreement or in any other written agreement between a participant and us, that the stock award will be subject to additional acceleration of vesting and exercisability in the event of a change in control.control (as defined in the 2019 Plan). For example, a stock award may provide for accelerated vesting upon the participant’s termination without cause or resignation for good reason in connection with a change in control. In the absence of such a provision, no such acceleration of the stock award will occur. Under

Repricings. The plan administrator may not: (i) reduce the 2012 Plan, a change in control is generally (i)exercise price of any outstanding options, or (ii) cancel any outstanding options that have an exercise price greater than the acquisition by a person or entity of more than 50% of our combined voting power other than by merger, consolidation or similar transaction; (ii) a consummated merger, consolidation or similar transaction immediately after which our stockholders cease to own more than 50%current fair market value of the combined voting powerCompany’s common stock in exchange for cash or other stock awards under the 2019 Plan, unless the stockholders of the surviving entity; (iii) a consummated sale, leaseCompany have approved such an action within twelve months prior to such an event.

Amendment and termination.The Board has the authority to amend, suspend, or exclusive license or other dispositionterminate the 2019 Plan, provided that such action does not materially impair the existing rights of all or substantially of our consolidated assets; or (iv) individuals who were Board members onany participant without such participant’s written consent. No ISOs may be granted after the date the 2012 Plan was adopted (the “Incumbent Board”) cease to constitute a majoritytenth anniversary of the Board, provided that if the appointment, election or nomination of any new Board member was approved by a majority of the members of the Incumbent Board then still in office, such new member will be considered to be a member of the Incumbent Board.

2015 Inducement Plan.

The 2015 Inducement Plan, which was adopted bydate our Board of Directors adopted the 2019 Plan.

2012 Equity Incentive Plan.

The 2012 Plan, which became effective in Julyconnection with our initial public offering in October 2012, and was in effect until the approval by our stockholders of 2015, providesour 2019 Plan in August 2019. The 2012 Plan provided for the grant of ISOs, NSOs, which maystock appreciation rights, restricted stock awards, restricted stock unit awards, performance-based stock awards, and other forms of equity compensation, or collectively, stock awards. Additionally, the 2012 Plan provided for the grant of performance cash awards. ISOs were to be granted only to persons as a material inducementemployees, subject to their commencement of employment with us, pursuantcertain limitations. All other awards could be granted to Rule 5635(c)(4) of the NASDAQ Listing Rules.employees, including officers, and tonon-employee directors and consultants.

Our Board of Directors, or a duly authorized committee thereof, hasadministered the authority to administer the 2015 Inducement2012 Plan. Our Board of Directors hashad delegated its authority to administer the 2015 Inducement2012 Plan to our Compensation Committee under the terms of our Compensation Committee’s charter. Grants under the 2015 Inducement Plan must be approved by the Compensation Committee (comprisedOur Board of independent directors)Directors also delegated certain authority to one or a majoritymore of our independent directors (as defined in Rule 5605(a)(2)officers. Our Board of Directors or its authorized committee is referred to herein as the NASDAQ Listing Rules) in orderplan administrator.

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Stock options are generally granted with an exercise price equal to comply with the exemption from the stockholder approval requirement for “inducement grants” provided under Rule 5635(c)(4) of the NASDAQ Listing Rules.

Initially, the aggregate number of sharesfair market value of our common stock thaton the date of grant, vest at the rate specified by the plan administrator (often over a four-year period) and may have a term up to a maximum of 10 years. The exercise price for an ISO or NSO generally cannot be issued pursuant to NSOs underless than 100% of the 2015 Inducement Plan was 1,000,000 shares. Asfair market value of December 31, 2015, there were 958,052 shares available for future grants underour common stock on the 2015 Inducement Plan. The termsdate of Inducement Plan and NSOs granted thereunder are generally the same asgrant. Unless the terms of an optionee’s stock option agreement provides otherwise, if an optionee’s service relationship with us, or any of our affiliates, ceases for any reason other than disability, death or cause, the optionee may generally exercise any vested options for a period of three months following the cessation of service. The option term may be extended in the event that exercise of the option following such a termination of service is prohibited by applicable securities laws or our insider trading policy. If an optionee’s service relationship with us, or any of our affiliates, ceases due to disability or death, or an optionee dies within a certain period following cessation of service, the optionee or a beneficiary may generally exercise any vested options for a period of 12 months in the event of disability and 18 months in the event of death. In the event of a termination for cause, options generally terminate immediately upon the termination of the individual. In no event may an option be exercised beyond the expiration of its term. Restricted stock units generally stop vesting upon the holder’s termination of service with us and any unvested restricted stock units are forfeited, unless otherwise provided in an agreement with the holder.

Corporate transactions. In the event of certain specified significant corporate transactions (as defined in the 2012 PlanPlan), the plan administrator has the discretion to take any of the following actions with respect to stock awards:

Change in control. The plan administrator may provide, in an individual award agreement or in any other written agreement between a participant and us, that the stock award will be subject to additional acceleration of vesting and exercisability in the event of a change in control (as defined in the 2012 Plan.Plan). For example, a stock award may provide for accelerated vesting upon the participant’s termination without cause or resignation for good reason in connection with a change in control. In the absence of such a provision, no such acceleration of the stock award will occur.

2012 Employee Stock Purchase Plan.

Additional long-term equity incentives are provided through the 2012 Employee Stock Purchase Plan (the “ESPP”), which became effective in connection with our initial public offering in October 2012. The ESPP is intended to qualify as an “employee stock purchase plan” within the meaning of Section 423 of the Code. Our Board of Directors has delegated its authority to administer the ESPP to our Compensation Committee. Under the ESPP, generally all of our regular employees (including our Named Executive Officers during their employment with us) may participate and may contribute, normally through payroll deductions, up to 15% of their earnings for the purchase of our common stock. The ESPP is implemented through a series of offerings of purchase rights to eligible employees. Under the ESPP, we may specify offerings with a duration of not more than six months,

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and may specify shorter purchase periods within each offering. Each offering will have one or more purchase

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dates on which our common stock will be purchased for employees participating in the offering. Unless otherwise determined by our Compensation Committee, shares are purchased for accounts of employees participating in the ESPP at a price per share equal to the lower of (a) 85% of the fair market value of our common stock on the first date of an offering or (b) 85% of the fair market value of our common stock on the date of purchase. As

DIRECTOR COMPENSATION

The following table shows certain information with respect to the compensation of allnon-employee directors of the Company for the fiscal year ended December 31, 2015, there2019:

Directors who are also employees do not receive cash or equity compensation for service on our Board of Directors in addition to the compensation payable for their service as our employees. We have anon-employee director compensation policy, or our director compensation policy, that became effective following our initial public offering. Under our director compensation policy, our Compensation Committee determines individualnon-employee members of our Board of Directors who will be eligible to receive compensation and who we refer to as our Eligible Directors. All of ournon-employee directors were 1,260,136Eligible Directors for 2019 compensation under our director compensation policy. Pursuant to our director compensation policy in effect in 2019, we provide cash compensation in the form of an annual retainer of $40,000 to each of our Eligible Directors and $70,000 to our Chairman of the Board. We also pay an additional annual retainer of $20,000 to the chairman of our Audit Committee, $10,000 to other independent Eligible Directors who serve on our Audit Committee, $12,000 to the chairman of our Compensation Committee, $6,000 to other independent Eligible Directors who

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serve on our Compensation Committee, $8,000 to the chairman of our Nominating and Corporate Governance Committee and $4,000 to other independent Eligible Directors who serve on our Nominating and Corporate Governance Committee. We have reimbursed and will continue to reimburse ournon-employee directors for travel, lodging and other reasonable expenses incurred in attending meetings of our Board of Directors and committees of our Board of Directors.

Pursuant to our director compensation policy, each Eligible Director who is first elected to our Board of Directors is granted an option to purchase shares available for future issuance underof the ESPP. On January 1, 2016, pursuantCompany’s common stock on the date of his or her initial election to our Board of Directors. The number of options is usually determined in December of the prior year. In addition, the Board of Directors also determines the number of stock options to be awarded to each directorre-elected at our next annual stockholder meeting.

Notwithstanding the terms of our director compensation policy, newly appointed and serving Eligible Directors did not receive a stock option grant at the ESPP,time of our annual stockholder meeting in August 2019, as our 2019 Plan was pending approval by our stockholders. Instead, in October 2019, following the numberapproval of the 2019 Plan by our stockholders, the Board of Directors, upon the recommendation of the Compensation Committee, approved (i) an initial option grant of 46,500 shares available for issuance under the ESPP automatically increased by 500,000to new Eligible Directors (Mr. Nunn and Dr. Simeonidis) and (ii) in order to properly incentivize and retain our serving Eligible Directors, an annual option grant to each Eligible Directorre-elected at our annual meeting of stockholders in 2019 of 46,500 shares.

401(k) Plan.

All of our full-time employees in the United States, including our Named Executive Officers, are eligibleEach initial option granted to participate in our 401(k) plan, which is a retirement savings defined contribution plan established in accordancesuch Eligible Directors described above will vest and become exercisable with Section 401(a)respect toone-third of the Code. Pursuant to our 401(k) plan, employees may elect to defer their eligible compensation into the plan on a pre-tax basis, upshares subject to the statutorily prescribed annual limit of $18,000 in 2015 (additional salary deferrals not to exceed $6,000 are available to those employees 50 years of age or older) and to haveoption on the amount of this reduction contributed to our 401(k) plan. We provide a $0.25 match for every dollar our employees elect to defer up to 6% of their eligible compensation. In general, eligible compensation for purposesfirst anniversary of the 401(k) plan includes an employee’s wages, salaries, fees for professional servicesdate of grant and other amounts received for personal services actually renderedthe balance of the shares will vest and become exercisable in a series of 24 equal monthly installments thereafter, such that the courseoption is fully vested on the third anniversary of employment with usthe date of grant, subject to the extentEligible Director continuing to provide services to us through such dates. Each annual option granted to such Eligible Directors described above will vest and become exercisable in 12 equal monthly installments such that the amounts are includible in gross income,option will be fully vested on the first anniversary of the date of grant, or as of the date of the next annual meeting of the Company’s stockholders, whichever occurs first and subject to certain adjustments and exclusions requiredthe Eligible Director continuing to provide services to us through such dates. The term of each option granted to an Eligible Director is 10 years.

The options granted to ournon-employee directors are granted under the Code. The 401(k) plan currently does not offer the ability to invest in our securities.

Potential Payments Upon Termination or Change in Control

Dr. Grint eligible to receive severance and change in control benefits under2019 Plan, the terms of his employment agreement, and each of Dr. Xanthopoulos, Dr. Gibson and Mr. Szekeres received severance paymentswhich are described in connection with their resignations, each as describedmore detail above under “—Employment Agreements with Named Executive Officers.” Additionally, stock options granted to Dr. Grint are subject to the change in control provisions set forth in the 2012 Plan as further described above under “—Equity“Equity Compensation Plans and Other Benefit Plans.Plans-2019 Equity Incentive Plan.”

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PROPOSAL 3

RATIFICATIONOF SELECTIONOF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

The Audit Committee has selected Ernst & Young LLP as the Company’s independent registered public accounting firm for the fiscal year ending December 31, 2020 and has further directed that management submit the selection of independent registered public accounting firm for ratification by the stockholders at the annual meeting. Ernst & Young has audited the Company’s financial statements since its incorporation in 2009. Representatives of Ernst & Young are expected to be present at the annual meeting. They will have an opportunity to make a statement if they so desire and will be available to respond to appropriate questions.

Neither the Company’s Bylaws nor other governing documents or law require stockholder ratification of the selection of Ernst & Young as the Company’s independent registered public accounting firm. However, the Audit Committee is submitting the selection of Ernst & Young to the stockholders for ratification as a matter of good corporate practice. If the stockholders fail to ratify the selection, the Audit Committee will reconsider whether or not to retain that firm. Even if the selection is ratified, the Audit Committee in its discretion may direct the appointment of different independent auditors at any time during the year if they determine that such a change would be in the best interests of the Company and its stockholders.

The affirmative vote of the holders of a majority of the shares present in person or represented by proxy and entitled to vote at the annual meeting will be required to ratify the selection of Ernst & Young. Abstentions will be counted toward the tabulation of votes on proposals presented to the stockholders and will have the same effect as negative votes.

Principal Accountant Fees and Services

The following table represents aggregate fees billed to the Company for the fiscal years ended December 31, 2019 and December 31, 2018, by Ernst & Young LLP, the Company’s principal accountant. All fees described below werepre-approved by the Audit Committee.

In connection with the audit of each of the 2019 and 2018 financial statements, the Company entered into engagement agreements with Ernst & Young, which sets forth the terms by which Ernst & Young will perform audit services for the Company. Such agreements are subject to alternative dispute resolution procedures.

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Pre-approval Policies and Procedures

The Audit Committee mustpre-approve the audit andnon-audit services rendered by the Company’s independent registered public accounting firm.

THE BOARDOF DIRECTORS RECOMMENDS

A VOTEFOR PROPOSAL 3

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EXECUTIVE OFFICERS

The following table sets forth our current executive officers, their ages, and the positions held by each such person with the Company:

Mr. Hagan’s biographical information is set forth above under Proposal 1.

Christopher Aker has served as our Senior Vice President and General Counsel since January 2019, and before that served as our Senior Director, Legal Affairs since February 2011. Prior to joining us, Mr. Aker served as the Senior Director, Administration and Senior Corporate Counsel for Phenomix Corporation, a privately-held biopharmaceutical company, and was responsible for operational and legal oversight. Prior to Phenomix, Mr. Aker was Senior Corporate Counsel at SUGEN, Inc., a wholly-owned subsidiary of Pharmacia, until its acquisition by Pfizer. Prior to SUGEN, Mr. Aker was in private practice with various law firms. Mr. Aker received his Bachelor of Arts degree in International Relations from the University of California, Davis and his J.D. from Santa Clara University.

Cris Calsada joined Regulus in August 2019 and currently serves as our Chief Financial Officer. Prior to joining us, she served as Chief Financial Officer for Sanifit Therapeutics, S.A. since December 2017. Prior to her employment with Sanifit, Ms. Calsada was self-employed as a finance consultant to various life sciences companies. From 2004 until its acquisition in 2015, she served in positions of increasing responsibility with Ambrx, Inc., most recently serving as its Chief Operating Officer and Vice President of Finance. Prior to Ambrx, she worked for Sony Online Entertainment as its Executive Director of Finance and Controller. Earlier in her career, she practiced as a certified public accountant. Ms. Calsada received a B.S. in Business Administration with emphasis in Accounting from San Diego State University and an M.B.A. from the University of Southern California Marshall School of Business.

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SECURITY OWNERSHIPOF CERTAIN BENEFICIAL OWNERSAND MANAGEMENT

The following table sets forth certain information regarding the ownership of the Company’s common stock as of March 31, 2020 by: (i) each of our directors; (ii) each of our Named Executive Officers as defined above under the heading “Executive Compensation”; (iii) each person known by us to beneficially own more than 5% of our common stock and (iv) all of our current executive officers and directors as a group.

Beneficial ownership is determined in accordance with the rules of the SEC and includes voting and investment power with respect to the securities. This table is based upon information supplied by officers, directors and principal stockholders and Schedules 13D and 13G filed with the SEC. Except as indicated by footnote, and subject to applicable community property laws, we believe the persons named in the table have sole voting and investment power with respect to all shares of common stock shown as beneficially owned by them.

Percentage of beneficial ownership is based on 27,608,783 shares of common stock outstanding as of March 31, 2020. The number of shares of common stock used to calculate the percentage ownership of each listed person includes the shares of common stock underlying options held by such persons that are exercisable, or restricted stock units which will vest, within 60 days following March 31, 2020. Unless otherwise indicated, the address for the persons and entities listed in the table below is c/o Regulus Therapeutics Inc., 10628 Science Center Drive, Suite 225, San Diego, CA 92121.

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Equity Compensation Plan Information

The following table provides information as of December 31, 2015,2019, with respect to shares of our common stock that may be issued under our existing equity compensation plans: