How can I find out the results of the voting at the SpecialAnnual Meeting?

Preliminary voting results will be announced at the SpecialAnnual 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 SpecialAnnual 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-K8‑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. Additionally, if this Form 8-K does not include the Company’s decision regarding the results of the vote on Proposal 4 included in these Proxy Materials, then we will file a Form 8-K on this topic no more than 150 calendar days after the end of the Annual Meeting, but in no event later than 60 calendar days prior to the deadline for submissions of stockholders proposals under Rule 14a-8 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”).

What proxy materials are available on the internet?internet?

We will make all of the Proxy Materials available on the Internet athttp://www.investorvote.com/ABIO, beginning on or about October 28, 2018,2019, and permit voting via the Internet and by telephone as of that date.

WhatNO PERSON IS AUTHORIZED TO GIVE ANY INFORMATION OR TO MAKE ANY REPRESENTATION OTHER THAN THOSE CONTAINED IN THIS PROXY STATEMENT, AND, IF GIVEN OR MADE, SUCH INFORMATION MUST NOT BE RELIED UPON AS HAVING BEEN AUTHORIZED. THE DELIVERY OF THIS PROXY STATEMENT SHALL, UNDER NO CIRCUMSTANCES, CREATE ANY IMPLICATION THAT THERE HAS BEEN NO CHANGE IN THE AFFAIRS OF ARCA SINCE THE DATE OF THIS PROXY STATEMENT.

Proposal No. 1

Election of Board of Directors

The Company’s Amended and Restated Certificate of Incorporation provides that the Board of Directors is divided into three classes to provide for staggered terms and that each director will serve for a term of three years or less, depending on the class to which the Board of Directors has assigned a director not previously elected by the stockholders. There are currently no vacancies on the deadlines for submitting stockholder proposalsBoard of Directors. Vacancies on the Board of Directors may be filled only by persons elected by a majority of the remaining directors. A director elected by the Board of Directors to fill a vacancy in a class, including vacancies created by an increase in the number of directors, shall serve for the remainder of the full term of that class and until the director’s successor is duly elected and qualified. The Company may reduce or increase the size of the Board of Directors by resolution adopted by the affirmative vote of a majority of the directors.

There are currently two Class I directors whose terms expire at the annual stockholders’ meeting in 2019, two Class II directors whose terms expire at the annual meeting?stockholders’ meeting in 2020 and two Class III directors whose terms expire at the annual meeting in 2021. The Board of Directors has nominated two Class I directors, Drs. Linda Grais and Anders Hove, for election to the Board of Directors, for a three-year term ending on the date of the annual stockholders meeting in 2022 or until their successors are duly elected and qualified or appointed.

ToIf elected at the Annual Meeting, Drs. Grais and Hove would serve until the 2022 annual stockholders meeting and until their successors have been duly elected and qualified, or, if sooner, until the director’s death, resignation or removal. It is the Company’s policy to encourage directors and nominees for director to attend the Annual Meeting. Five of the Company’s directors then on the Board of Directors attended the 2018 Annual Meeting of Stockholders in person, and one attended by telephone.

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 two nominees receiving the highest number of affirmative votes will be elected. Each person nominated for election has agreed to serve if elected. The Company’s management has no reason to believe that either nominee will be unable to serve.

Director Qualifications and Diversity

The below paragraphs provide information, as of the date of this proxy statement, about each nominee and current members of the Board of Directors, including age, all positions currently held, principal occupation and business experience for the past five years. In addition to the information presented regarding each nominee’s specific experience, qualifications, attributes and skills that led the Board of Directors to conclude that such director or nominee should be able to serve as a director, the Board of Directors also believes that all of the directors and nominees have a reputation of integrity, honesty and adherence to high ethical standards. They each have demonstrated business acumen and an ability to exercise sound judgment as well as a commitment to service to ARCA and the Board of Directors.

Our Nominating and Corporate Governance Committee of the Board of Directors (the “Nominating and Corporate Governance Committee”) considers diversity in the director identification and nomination process. The Nominating and Corporate Governance Committee seeks nominees with a broad diversity of experience, professions, skills, geographic representation and backgrounds. The Nominating and Corporate Governance Committee does not assign specific weights to particular criteria and no particular criterion is necessarily applicable to all prospective nominees. We believe that the backgrounds and qualifications of the directors, considered as a group, should provide a significant composite mix of experience, knowledge and abilities that will allow the Board of Directors to fulfill its responsibilities. Nominees are not discriminated against on the basis of race, religion, national origin, sexual orientation, disability or any other basis proscribed by law.

Nominee for inclusionElection for a Three-year Term Expiring at the 2022 Annual Meeting

The Board Of Directors Recommends

A Vote In Favor Of The Named Nominees.

Linda Grais, M.D.

Dr. Grais, age 63, has served as a member of the Board of Directors since May 2007. Dr. Grais has been a director of Ocera Therapeutics, Inc., a public biopharmaceutical company, since January 2008 and became President and Chief Executive Officer of Ocera in next year’s proxy materials, your proposalJune 2012, and served in that role until Ocera’s acquisition by Mallinckrodt Pharmaceuticals in December 2017. Dr. Grais served as a Managing Member at InterWest Partners, a venture capital firm from May 2005 until February 2011. From July 1998 to July 2003, Dr. Grais was a founder and executive vice president of SGX Pharmaceuticals Inc., a drug discovery company. Prior to that, she was a corporate attorney at Wilson Sonsini Goodrich & Rosati, where she practiced in such areas as venture financings, public offerings and strategic partnerships. Before practicing law, Dr. Grais worked as an assistant clinical professor of Internal Medicine and Critical Care at the University of California, San Francisco. Dr. Grais received a B.A. from Yale University, magna cum laude, and Phi Beta Kappa, an M.D. from Yale Medical School and a J.D. from Stanford Law School. Since September 2015, Dr. Grais has served on the board of PRA Health Sciences, a public contract research organization. Dr. Grais also joined the boards of Corvus Pharmaceuticals and Zosano Pharma Corp., both publicly traded pharmaceutical companies, in January 2019. We believe Dr. Grais is an appropriate member of the Board of Directors because of her diverse training and experience as both a medical doctor and a lawyer, her experience as a founder and senior executive of a pharmaceutical company, and her experience as an investor in new life sciences companies. She also has extensive experience with and knowledge of the Company's business from her service on the Board of Directors of the Company since 2007.

Anders Hove, M.D.

Dr. Hove, age 53, has served as a member of the Board of Directors since February 2017. Dr. Hove is the manager of Acorn Bioventures, a partnership focusing on long-term investments in biotech, specialty pharma and medical device companies. Dr. Hove was most recently a managing partner at Amzak Health from 2017 to 2019 and before that, a general partner of Venrock Associates, a venture capital firm, which he joined in 2004 and remained at through 2016. In 2008, Dr. Hove was a founder of Venrock Healthcare Capital Partners, Venrock’s public funds focused on small capitalization biotech companies and late-stage private companies. From 1996 to 2004, Dr. Hove was a fund manager at BB Biotech Fund, an investment firm, and from 2002 to 2003 he also served as Chief Executive Officer of Bellevue Asset Management, LLC, an investment company. Dr. Hove previously held senior level positions in the medical, clinical and business operations of the pharmaceuticals division of Ciba-Geigy and Novartis. Mr. Hove was a member of the boards of directors of Anacor Pharmaceuticals, a publicly traded pharmaceutical company, from 2005 until its acquisition by Pfizer in June 2016, and Edge Therapeutics, a publicly traded biotechnology company, from 2015 to 2016. In addition, Dr. Hove is a member of the board of directors of MC2 Therapeutics. He received a M.Sc. in Biotechnology Engineering from the Technical University of Denmark, an M.D. from the University of Copenhagen and an M.B.A. from the Institut Européen d'Administration des Affaires. We believe Dr. Hove is an appropriate member of the Company’s Board of Directors, given his extensive training and experience as a medical doctor and masters of business administration, an executive in the pharmaceutical industry, and as an investor in biotechnology companies.

Directors Continuing in Office Until the 2020 Annual Meeting

Michael R. Bristow, M.D., Ph.D.

Dr. Bristow, age 74, was one of the founders of ARCA in September 2004, and has served as a Director since that time. Dr. Bristow has also served as the Company’s President and Chief Executive Officer since July 2009. Previously, Dr. Bristow served as the President and Chief Executive Officer of the Company from September 2004 to November 2006, and as the Company’s Chief Science and Medical Officer from November 2006 to July 2009. Dr. Bristow is a Professor of Medicine and the former Head of Cardiology at the University of Colorado Health Sciences Center, where he has been since October 1991. Dr. Bristow was one of the founders of Myogen, Inc. and served as Myogen’s Chief Science and Medical Officer from October 1996 to February 2006 and as a Scientific Advisor to Myogen from February 2006 until the acquisition of Myogen by Gilead Sciences, Inc. in November 2006. We believe Dr. Bristow is an appropriate member of the Company’s Board of Directors given his extensive experience and expertise as a cardiologist, medical researcher and drug developer in the field of cardiovascular medicine, and heart failure specifically, and his experience as a founder and manager of cardiovascular-focused, public pharmaceutical company. Dr. Bristow also has extensive experience with, and knowledge of, ARCA’s business, as the founder and former Chief Science and Medical Officer of the Company, and the current President and Chief Executive Officer of ARCA, and as a member of the Board of Directors of ARCA since the founding of the Company. Dr. Bristow holds a M.D. and Ph.D. from the University of Illinois.

Robert E. Conway

Mr. Conway, age 65, was appointed to the Board of Directors in September 2013, and has served as the Chairman of our Board of Directors since 2014. Mr. Conway served as the Chief Executive Officer and member of the board of directors of Array Biopharma, a publicly traded pharmaceutical company, from 1999 to 2012. Prior to joining Array, Mr. Conway was the Chief Operating Officer and Executive Vice President of Hill Top Research, Inc., from 1996 to 1999. From 1979 until 1996, Mr. Conway held various executive positions for Corning Inc. including Corporate Vice President and General Manager of Corning Hazleton, Inc., a contract research organization. From 2004 to 2013, he served on the board of directors of PRA International, Inc., which was a public company for a portion of his tenure there, from 2012 to the present, he has served on the board of directors of eResearch Technology, Inc., a private company, and from 2015 to July 2017, he has served on the board of directors of Nivalis Therapeutics, Inc. a public, clinical stage pharmaceutical company. In July 2017, Nivalis Therapeutics, Inc. combined with Alpine Immune Sciences, Inc., a public, clinical stage pharmaceutical company, and Mr. Conway continues to serve on the board of directors following such combination. In addition, Mr. Conway is a member of the Strategic Advisory Committee of Genstar Capital, LLC and is a member of the board of directors of Signant Health and Adverra, Inc. Mr. Conway received a B.S. in accounting from Marquette University in 1976. We believe Mr. Conway is an appropriate member of the Board of Directors given his experience and expertise in the pharmaceutical industry, in pharmaceutical development and clinical trials, and in corporate finance, governance, accounting and public company compliance.

Directors Continuing in Office Until the 2021 Annual Meeting

Raymond L. Woosley, M.D., Ph.D.

Dr. Woosley, age 76, was appointed to the Board of Directors in July 2013. Since 2012, Dr. Woosley is the Director of the Arizona Center for Education and Research on Therapeutics, an independent, nonprofit research and education organization. Dr. Woosley is currently the President Emeritus of the Critical Path Institute, a non-profit, public-private partnership with the Federal Food and Drug Administration, of which he was a founder in November 2004, and where he served as President, Chief Executive Officer and Chairman of the board of directors from 2005 to 2011. Since 2001, Dr. Woosley has also been a Professor of Medicine and Pharmacology at The University of Arizona Health Sciences Center, and, since 2012, Professor Emeritus, where he was also Vice President for Health Sciences from 2001 to 2005, and Dean of the College of Medicine from 2001 to 2002. Since 2015, he has been Professor of Medicine in the University of Arizona, College of Medicine-Phoenix. From 1988 to 2001, Dr. Woosley was a professor of medicine at the Georgetown University School of Medicine, where he was also Director of the Institute of Cardiovascular Sciences from 1994 to 2000, and Division Chief, Clinical Pharmacology, in the Department of Medicine from 1988 to 1994. Dr. Woosley earned his Ph.D. in Pharmacology from the University of Louisville and his M.D. from the University of Miami. We believe Dr. Woosley is an appropriate member of the Board of Directors, given his expertise and experience in cardiovascular clinical pharmacology, anti-arrhythmic therapeutics, pharmacogenetic drug development and therapeutic regulatory approval.

Dan J. Mitchell

Mr. Mitchell, age 62, was appointed to the Board of Directors in February 2014. He founded, and is a manager of Sequel Venture Partners, L.L.C., a venture capital firm formed in January 1997. Prior to founding Sequel Venture Partners, Mr. Mitchell was a founder of Capital Health Venture Partners, a health care focused venture capital firm, where he was a General Partner from October 1986 until 2006, and he was in the Venture Capital Division of the Trust Department of the First National Bank of Chicago from 1983 to 1985. He currently serves on the board of directors of several private companies. Mr. Mitchell holds a B.S. from the University of Illinois and an M.B.A. from the University of California at Berkeley. We believe Mr. Mitchell is an appropriate member of the Board of Directors given his expertise and experience in the pharmaceutical industry, pharmaceutical development, and in corporate finance and governance.

Information Regarding the Board of Directors and Corporate Governance

Independence of The Board of Directors

As required under the Nasdaq Stock Market (“Nasdaq”) listing standards, a majority of the members of a listed company’s board of directors must be submittedqualify as “independent,” as affirmatively determined by the board of directors. Our Board of Directors consults with the Company’s counsel to ensure that the Board of Directors’ determinations are consistent with relevant securities and other laws and regulations regarding the definition of “independent,” including those set forth in writing by December 19, 2018,pertinent listing standards of the Nasdaq, as in effect from time to ARCA’s Secretary at 11080 CirclePoint Road, Suite 140, Westminster, Colorado, 80020. If you wish to submittime.

Consistent with these considerations, after review of all relevant identified transactions or relationships between each director, or any of his or her family members, and the Company, its senior management and its independent registered public accounting firm, the Board of Directors has affirmatively determined that the following five directors are independent directors within the meaning of the applicable Nasdaq listing standards: Mr. Conway, Dr. Grais, Mr. Mitchell, Dr. Hove and Dr. Woosley. In making this determination, the Board of Directors found that none of the directors or nominees for director had a proposal thatmaterial or other disqualifying relationship with the Company. Dr. Bristow, the Company’s President and Chief Executive Officer, is not an independent director by virtue of his employment relationship with the Company.

Board Leadership Structure

The Company has structured its Board of Directors in a way that the Company believes effectively serves its objectives of corporate governance and management oversight. The Company separates the roles of Chief Executive Officer and Chairman of the Board of Directors in recognition of the differences between the two roles. The Company believes that the Chief Executive Officer should be responsible for the day to be includedday leadership and performance of the Company, while the Chairman of the Board of Directors should work with the Chief Executive Officer and the rest of the Board of Directors to set the strategic direction for the Company and provide guidance to, and oversight of the Chief Executive Officer. The Chairman also sets the agenda for meetings of the Board of Directors and presides over them.

Mr. Conway, who is an independent director, was elected Chairman of the Board of Directors in next year’s proxy materials2014. In this capacity, Mr. Conway, among other things, calls and presides over Board meetings, including meetings of the independent directors, and sets meeting agendas. In this role, Mr. Conway can effectively coordinate between the Board of Directors and management regarding risk management issues and the implementation of appropriate responses, and can help ensure the effective independent functioning of the Board of Directors in its oversight responsibilities. Accordingly, the Chairman has substantial ability to shape the work of the Board of Directors.

Role of the Board of Directors in Risk Oversight and Risk Management

One of the Board of Directors’ key functions is informed oversight of the Company’s 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 the Board of Directors that address risks inherent in their respective areas of oversight. In particular, while the Board of Directors is responsible for monitoring and assessing strategic risk exposure, the Audit Committee has the responsibility to consider and discuss the major financial risk exposures and the steps 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, in addition to oversight of the performance of ARCA’s accounting and financial reporting processes. The Nominating and Corporate Governance Committee monitors the effectiveness of the corporate governance guidelines, including whether they are successful in preventing illegal or nominateimproper liability-creating conduct. The Compensation Committee of the Board of Directors (the “Compensation Committee”) assesses and monitors whether any compensation policies and programs have the potential to encourage excessive risk-taking. The entire Board of Directors and its committees address risk management issues from time-to-time and at least annually meet with the employees responsible for risk management in the committees’ respective areas of oversight. Both the Board of Directors as a whole and the various standing committees receive periodic reports from the employees responsible for risk management, as well as incidental reports as matters may arise. It is the responsibility of the committee chairs to report findings regarding material risk exposures to the Board of Directors as quickly as possible.

Meetings of The Board of Directors

The Board of Directors met eight times during the 2018 fiscal year. The independent members of the Board of Directors met separately as a group at four of the board meetings in 2018. All members of the Board of Directors attended at least 75% of the meetings of the Board of Directors and at least 75% the meeting of the committees of the Board of Directors of which each director you must do sowas a member.

Information Regarding Committees of the Board of Directors

The Board of Directors has three standing committees: The Audit Committee, the Compensation Committee, and the Nominating and Corporate Governance Committee. The following table provides membership and meeting information for the fiscal year ended December 31, 2018, for each of the committees of the Board of Directors:

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. The Board of Directors has determined that each member of each committee meets the applicable Nasdaq 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 regarding the Company.

Audit Committee

The Audit Committee was established by no earlier than March 2, 2019,the Board of Directors in accordance with Section 3(a)(58)(A) of the Exchange Act, to oversee the Company’s corporate accounting and no later than April 1, 2019. You are also advisedfinancial reporting processes and audits of its financial statements. For this purpose, the Audit Committee performs several functions. The Audit Committee evaluates the performance of and assesses the qualifications of the independent registered public accounting firm; determines and approves the engagement of the independent registered public accounting firm; determines whether to retain or terminate the existing independent registered public accounting firm or to appoint and engage a new independent registered public accounting firm; reviews and approves the retention of the independent registered public accounting firm to perform any proposed permissible non-audit services; monitors the rotation of partners of the independent registered public accounting firm 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 registered public accounting firm 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, 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 Bylaws, which contain additional requirements about advance noticeannual audited financial statements and quarterly financial statements with management and the independent registered public accounting firm, including a review of stockholder proposalsthe Company’s disclosures under the “Management’s Discussion and director nominations.

5

PROPOSAL NO. 1

APPROVAL OF CERTIFICATES OF AMENDMENT TO THE COMPANY’S

RESTATED CERTIFICATE OF INCORPORATION TO EFFECT A REVERSE STOCK SPLIT

Introduction

Analysis of Financial Condition and Results of Operations” discussion in its Annual Reports on Form 10-K and Quarterly Reports on Form 10-Q. The Audit Committee is composed of three directors: Mr. Conway (chair), Mr. Mitchell and Dr. Grais. The Audit Committee met four times during the fiscal year. The Board of Directors has adopted a resolution approving,written charter of the Audit Committee that is available to stockholders on the Company’s website at www.arcabio.com.

The Board of Directors reviews the Nasdaqlisting standards definition of independence for audit committee members on an annual basis and has determined that all members of the Audit Committee are independent (as independence is currently defined in Rule 5605(c)(2)(A)(i) and (ii) of the Nasdaqlisting standards).The Board of Directors has also determined that Mr. Conway qualifies as an “audit committee financial expert,” as defined in applicable SEC rules.The Board of Directors made a qualitative assessment of Mr. Conway’s level of knowledge and experience based on several factors, including his prior experience, business acumen and independence.

Report of the Audit Committee of the Board of Directors¹

The Audit Committee has reviewed and discussed the audited financial statements for the fiscal year ended December 31, 2018, with management of the Company. The Audit Committee has discussed with the independent registered public accounting firm the matters required to be discussed by Public Company Accounting Oversight Board (“PCAOB”) Auditing Standard No. 1301, Communications with Audit Committees. 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 registered public accounting firm’s communications with the Audit Committee concerning independence, and has discussed with the 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 on Form 10-K for the fiscal year ended December 31, 2018.

Mr. Robert Conway

Mr. Dan Mitchell

Dr. Linda Grais

Compensation Committee

The Compensation Committee is currently composed of three directors: Mr. Conway, Dr. Grais (chair) and Dr. Woosley. All members of the Compensation Committee are independent, as independence is currently defined in Rule 5605(a)(2) of the Nasdaq listing standards. The Compensation Committee met one time during the fiscal year. The Compensation Committee has adopted a written charter that is available to stockholders on the Company’s website at www.arcabio.com.

The Compensation Committee of the Board of Directors acts on behalf of the Board of Directors to review, adopt and oversee the Company’s compensation strategy, policies, plans and programs, including:

Compensation Committee Processes and Procedures

The Compensation Committee meets on a regular basis as it deems appropriate. The agenda for each meeting is usually developed by the Chair of the Compensation Committee. The Compensation Committee meets regularly in executive session. However, from time to time, various members of management and other employees as well as outside 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 or individual performance objectives. 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. In general, the Compensation Committee has set executive compensation to be in line with peer companies identified by the Compensation Committee and to incentivize the Company’s executive officers in achieving the Company’s short- and long-term corporate goals.

In setting 2017 and 2018 base salary and cash bonus award amounts for the Named Executive Officers (as defined below), the Compensation Committee considered peer group data and factors specific to the Company, and targeted cash compensation to be consistent with these metrics. For the fiscal year ended December 31, 2017, the Compensation Committee recommended, and the Board of Directors approved, a base salary of $295,359 for Dr. Bristow, the Company’s President and Chief Executive Officer, a base salary of $294,170 for Mr. Keuer, the Company’s Chief Operating Officer, and a base salary of $288,683 for Mr. Ozeroff, the Company’s Senior Vice President and General Counsel. In March 2018, the Compensation Committee recommended, and the Board of Directors approved cash bonuses based on previous performance for the Named Executive Officers for their performance in the fiscal year ended December 31, 2017. There were no changes to the Named Executive Officers’ salaries for 2018 or 2019. Additionally, the Compensation Committee recommended that no bonuses be paid to the Named Executive Officers for performance in the fiscal year ended December 31, 2018 and has not approved a cash bonus plan for performance in the fiscal year ended December 31, 2019.

In May 2019, the Named Executive Officers agreed to a voluntary 10% salary reduction for the remainder of 2019. As a result of this reduction, the base salary to be paid to the Named Executive Officer’s for 2019 is as follows:

The foregone portion of any salary otherwise owed to each Named Executive Officer shall not be paid without the prior approval of the Board of Directors, provided, that such foregone amounts shall be included in each Named Executive Officer’s base salary for purposes of calculating any severance amounts which may be owed in the future under the terms of such Named Executive Officer’s employment agreement with the Company.

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 first 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.

The Compensation Committee reviews and approves the compensation of the Chief Executive Officer and the other executive officers of the Company, including annual base salaries, annual and long-term incentive or bonus awards, employment agreements, and severance and change in control agreements/provisions, in each case as, when and if appropriate, and any special or supplemental benefits. For executives other than the Chief Executive Officer, the Compensation Committee solicits and considers evaluations and recommendations submitted to the Compensation Committee by the Chief Executive Officer. The Compensation Committee evaluates the performance of the Chief Executive Officer in light of Company and individual goals and objectives, and makes appropriate recommendations for improving performance. In performing the evaluation, the Chair of the Compensation Committee may solicit comments from the other non-employee members of the Board of Directors and lead the Board of Directors in an overall review of the Chief Executive Officer’s performance in an executive session of non-employee members of the Board of Directors. If the compensation for the Chief Executive Officer or any other executive officer is governed by an employment agreement, the Compensation Committee approves such employment agreement and any amendments thereto.

For all executives 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.

The Compensation Committee also considers the results of any “say-on-pay” vote of the Company’s stockholders bothwith regard to select the specific exchange ratio withincompensation of the designated rangeCompany’s executive officers when making compensation decisions. At the 2016 annual meeting of between1-for-3 and1-for-20, inclusive,stockholders, the Company’s stockholders approved, on an advisory basis, the compensation of the Company’s named executive officers as described in the proxy statement for such annual meeting. The Compensation Committee believes that this advisory vote supports that the Company’s current compensation practices are aligned with the best interests of stockholders and anticipates taking into account the results of the advisory vote included as Proposal 3 in these Proxy Materials (and any subsequent advisory vote on executive compensation) when making compensation decisions in the future.

Nominating and Corporate Governance Committee

The Nominating and Corporate Governance Committee is responsible for identifying, reviewing and evaluating candidates to serve as directors of the Company (consistent with criteria approved by the Board of Directors), reviewing and evaluating incumbent directors, recommending to the Board of Directors candidates for election to the Board of Directors, making recommendations to the Board of Directors regarding compensation for service on the Board of Directors and the committees thereof, making recommendations to the Board of Directors regarding the membership of the committees of the Board of Directors, assessing the performance of the Board of Directors and developing a set of corporate governance principles for the Company. The Nominating and Corporate Governance Committee is composed of three directors: Dr. Hove, Mr. Mitchell and Dr. Woosley (chair). All members of the Nominating and Corporate Governance Committee in 2018 were independent (as independence is currently defined in Rule 5605(a)(2) of the Nasdaq listing standards). The Nominating and Corporate Governance Committee met three times during the 2018 fiscal year. The Nominating and Corporate Governance Committee has adopted a written charter that is available to stockholders on the Company’s website at www.arcabio.com.

The Nominating and Corporate Governance Committee periodically reviews the compensation of non-employee Directors for service on the Board of Directors and committees thereof. In 2015, the Nominating and Corporate Governance Committee began a review of its Director compensation levels considering general market conditions in the life science industry, and in comparison to other clinical stage biopharmaceutical companies, and in early 2016, the Committee recommended, and the Board of Directors approved, revised compensation for non-employee Directors, discussed in “Director Compensation” below. Since adoption of this policy, the Nominating and Corporate Governance Committee has reviewed Director compensation on an annual basis and has not made any changes.

The Board of Directors has adopted a process for identifying and evaluating director nominees, including stockholder nominees. Before recommending an individual to the Board of Directors for membership on the Board of Directors, the Nominating and Corporate Governance Committee canvasses its members and the Company’s management team for potential candidates for the Board of Directors. The Nominating and Corporate Governance Committee also uses its network of contacts to decide whether or notidentify potential candidates and, if it deems appropriate, may also engage a professional search firm. The Nominating and Corporate Governance Committee will consider stockholders’ recommendations for nominees to proceed to effect a Reverse Stock Split or instead to abandon the proposed certificates of amendment altogether. If a certificate of amendmentserve as director if notice is filed withtimely received by the Secretary of Statethe Company. Candidates nominated by stockholders will be evaluated in the same manner as other candidates. The Nominating and Corporate Governance Committee keeps the Board of Directors apprised of its discussions with potential nominees, and the names of potential nominees received from its current directors, management, and stockholders, if the stockholder notice of nomination is timely made.

Although the Board of Directors has not adopted a fixed set of minimum qualifications for candidates for membership on the Board of Directors, the Nominating and Corporate Governance Committee generally considers several factors in its evaluation of a potential member, such as the candidate’s education, professional background and field of expertise including industry or academic experience in the pharmaceutical and biotechnology fields, experience in corporate governance and management, the reasonable availability of the State of Delaware, the certificate of amendmentpotential member to devote time to the Restated Certificate of Incorporation will effect the Reverse Stock Split by reducing the outstanding number of sharesaffairs of the Company’s Common Stock by the ratio to be determinedCompany, as well as any other criteria deemed relevant by the Board but will not increaseof Directors or the par valueNominating and Corporate Governance Committee. 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 of Directors, 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 of Directors and the Company, to maintain a balance of knowledge, experience and capability. The Nominating and Corporate Governance Committee believes it is essential that Board of Directors members come from a variety of backgrounds and experiences.

In the case of incumbent directors whose terms of office are set to expire, the Nominating and Corporate Governance Committee reviews these directors’ overall contributions to the Company and the Board of Directors during their terms, including level of attendance, level of participation, quality of performance and contribution to the Board of Directors’ responsibilities and actions, and any 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 Nasdaq and SEC purposes, which determination is based upon applicable Nasdaqlisting standards, applicable SEC rules and regulations and the advice of counsel, if necessary. 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 of Directors. The Nominating and Corporate Governance Committee meets to discuss and consider the candidates’ qualifications and then determines whether to recommend a nominee to the Board of Directors by majority vote.

Stockholders who wish to recommend individuals for consideration by the Nominating and Corporate Governance Committee to become nominees for election to the Board of Directors may do so by delivering a written recommendation to the Nominating and Corporate Governance Committee addressed to the Corporate Secretary, between 60 and 90 days before the one year anniversary date of ARCA’s last annual meeting of stockholders. Recommendations must include the full name of the proposed nominee, a description of the proposed nominee’s business experience for at least the previous five years, complete biographical information, a description of the proposed nominee’s qualifications as a director, and a representation that the recommending stockholder is a beneficial or record owner of ARCA’s stock. Any such submission must be accompanied by the written consent of the proposed nominee to be named as a nominee and to serve as a director if elected. To date, the Nominating and Corporate Governance Committee has not rejected a timely director nominee from a stockholder.

In 2018, the Nominating and Corporate Governance Committee did not pay any fees to assist in the process of identifying or evaluating director candidates.

Stockholder Communications With The Board Of Directors

Stockholders who wish to communicate with the Board of Directors may do so by e-mail by using the following email address: directors@arcabio.com; or by mail by following the directions as set forth on ARCA’s website at www.arcabio.com, under the section titled “Corporate Governance” and the subsection titled “Governance Documents”.

Code of Business Conduct and Ethics

The Company has adopted the ARCA biopharma, Inc. Code of Business Conduct and Ethics that applies to all officers, directors and employees. The Code of Business Conduct and Ethics is available on the Company’s Common Stock,website at www.arcabio.com. If the Company makes any substantive amendments to the Code of Business Conduct and Ethics or grants any waiver from a provision of the Code of Business Conduct and Ethics to any executive officer or director, the Company will promptly disclose the nature of the amendment or waiver on its website and file any current report on Form 8-K required by applicable law or Nasdaq listing standards.

Proposal 2

Ratification of Selection of the Independent Registered Public Accounting Firm

The Audit Committee has selected KPMG as the Company’s independent registered public accounting firm for the fiscal year ending December 31, 2019, and has further directed that management submit the selection of the independent registered public accounting firm for ratification by the stockholders at the Annual Meeting. KPMG has audited the Company’s fiscal year financial statements since 2006. Representatives of KPMG are expected to be present at the Annual Meeting. They will have an opportunity to make a statement if they so desire and will not changebe available to respond to appropriate questions.

Neither the number of authorized sharesCompany’s Bylaws nor other governing documents or law require stockholder ratification of the selection of KPMG as the Company’s Common Stock.independent registered public accounting firm. However, the Board of Directors is submitting the selection of KPMG to the stockholders for ratification as a matter of good corporate practice. If the Board does not implement an approved Reverse Stock Split priorstockholders fail to theone-year anniversary of this meeting,ratify the Boardselection, the Audit Committee will seek stockholder approval before implementing any Reverse Stock Split afterreconsider whether to retain that time.

By approving Proposal No. 1 andfirm. Even if the Reverse Stock Split, stockholders will approve eachselection is ratified, the Audit Committee in its discretion may direct the appointment of a series of certificates of amendment todifferent independent registered public accounting firm at any time during the Restated Certificate of Incorporation pursuant to which any whole number of outstanding shares, between and including three and twenty,year if they determine that such a change would be combined into one share of the Company’s Common Stock, and authorize the Board to file only one such certificate of amendment, as determined by the Board in the manner described herein, and to abandon each certificate of amendment not selected by the Board. If approved, the Board may also elect not to effect any Reverse Stock Split and consequently not to file any certificate of amendment to the Restated Certificate of Incorporation. The Board believes that stockholder approval of the series of certificates of amendment granting the Board this discretion, rather than approval of a specified exchange ratio, provides the Board with maximum flexibility to react to then-current market conditions and, therefore, is in the best interests of the Company and its stockholders.

The Company’s Nasdaq Listing Compliance

The Company’s Common Stock is listed on the Nasdaq Capital Market under the symbol “ABIO.” To maintain a listing on the Nasdaq Capital Market, the Company must satisfy the applicable listing maintenance standards established by Nasdaq Stock Market LLC (“Nasdaq”). Among other things, the Company is required to comply with the continued listing requirements of the Nasdaq Capital Market (the “Nasdaq Capital Requirements”). To comply with the Nasdaq Capital Requirements, the Company must meet each of the following requirements:

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To comply with the Nasdaq Capital Requirements, the Company must also meet at least one of the following requirements:

Currently, the Company meets the Nasdaq Capital Requirements, except the $1.00 minimum bid price. Assuming the stockholders approve Proposal No. 1, the Board will determine whether to effect a Reverse Stock Split in the range of between1-for-3 and1-for-20, inclusive, at the ratio determined by the Board to be most likely sufficient to allow the Company to meet and maintain the $1.00 minimum bid price requirement.

Reasons for the Reverse Stock Split

On April 11, 2018, Nasdaq notified us that the bid price of our Common Stock had closed below the required $1.00 per share for 30 consecutive trading days, and, accordingly, that we did not comply with the applicable Nasdaq minimum bid price requirement. We have been provided 180 calendar days by Nasdaq to regain compliance with this requirement. We may be eligible for an additional 180 day extension from Nasdaq.

The Board has considered the potential harm to us of a delisting of our Common Stock and has determined that, if our Common Stock continues to trade below $1.00 per share, the consummation of the Reverse Stock Split is the best way to maintain liquidity by achieving compliance with the Nasdaq Capital Requirements. Approval of Proposal No. 1 will permit us to file one certificate of amendment to the Restated Certificate of Incorporation and the certificate of amendment filed thereby will contain the number of shares selected by the Board within the limits set forth in Proposal No. 1 to be combined into one share of Common Stock.

The Board also believes that the current low per share market price of our Common Stock has a negative effect on the marketability of our existing shares. The Board believes there are several reasons for this effect. First, certain institutional investors have internal policies preventing the purchase oflow-priced stocks. Second, a variety of policies and practices of broker-dealers discourage individual brokers within those firms from dealing inlow-priced stocks. Third, because the brokers’ commissions onlow-priced stocks generally represent a higher percentage of the stock price than commissions on higher priced stocks, the current share price of our Common Stock can result in individual stockholders paying transaction costs (commissions, markups or markdowns) that are a higher percentage of their total share value than would be the case if the share price of the Common Stock were substantially higher. This factor is also believed to limit the willingness of some institutions to purchase the Common Stock. The Board anticipates that a Reverse Stock Split will result in a higher bid price for our Common Stock, which may help to alleviate some of these problems.

If Proposal No. 1 is approved by the holders of our Common Stock and the Board decides to implement the Reverse Stock Split, the Board will determine the ratio of the Reverse Stock Split, in the range of between1-for-3 and1-for-20, inclusive, as determined in the judgment of the Board to be most likely sufficient to allow us to achieve and maintain compliance with the minimum $1.00 per share requirement for listing on the Nasdaq Capital Market for the longest period of time while retaining sufficient number of outstanding, tradeable shares to facilitate an adequate market. By way of illustration, assuming a per share price of $                , which represents the closing price of our Common Stock on the Nasdaq Capital Market on the Record Date, immediately prior to the filing of the appropriate certificate of amendment to the Restated Certificate of Incorporation, the Board may determine that we should effect a1-for-3 or1-for-20 reverse stock split, with the goal of achieving a bid price of $                 or $                 per share, respectively. Please refer to the section entitled “Effects of the Reverse Stock Split” below for more

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detailed examples of the effects of the range of ratios.

We believe that maintaining listing on the Nasdaq Capital Market will provide us with a market for the Common Stock that is more accessible than if our Common Stock were traded on the OTC Bulletin Board or in the “pink sheets” maintained by the OTC Markets Group, Inc. Such alternative markets are generally considered to be less efficient than, and not as broad as, the Nasdaq Capital Market. Among other factors, trading on the Nasdaq Capital Market increases liquidity and may potentially minimize the spread between the “bid” and “asked” prices quoted by Market Makers (as defined in Nasdaq Rule 5005). Further, a Nasdaq Capital Market listing may enhance our access to capital, increase our flexibility in responding to anticipated capital requirements and facilitate the use of our Common Stock in any strategic or financing transactions that it may undertake. We believe that prospective investors will view an investment in us more favorably if our shares qualify for listing on the Nasdaq Capital Market as compared with the OTC markets.

We expect that a Reverse Stock Split of our Common Stock will increase the market price of the Common Stock so that we are able to maintain compliance with the Nasdaq minimum bid price listing standard. However, the effect of a Reverse Stock Split on the market price of the Common Stock cannot be predicted with any certainty, and the history of similar stock split combinations for companies in like circumstances is varied. It is possible that the per share price of the Common Stock after the Reverse Stock Split will not rise in proportion to the reduction in the number of shares of the Common Stock outstanding resulting from the Reverse Stock Split, effectively reducing our market capitalization, and there can be no assurance that the market price per post-reverse split share will either exceed or remain in excess of the $1.00 minimum bid price for a sustained period of time. The market price of our Common Stock may vary based on other factors that are unrelated to the number of shares outstanding, including our future performance.

In order to maintain the listing on the Nasdaq Capital Market, we must maintain compliance with the Nasdaq Capital Requirements. As of June 30, 2018, the Company’s Market Value (as defined in Nasdaq Rule 5005) of Listed Securities (as defined in Nasdaq Rule 5005) was $7,741,647, our market value of Publicly Held Shares (as defined in Nasdaq Rule 5005) was $7,650,869 and our stockholders’ equity was $8,998,000. Even if we meet the bid price requirement, if we are unable to comply with the other Nasdaq Capital Requirements, Nasdaq may determine to delist the Company’s Common Stock from the Nasdaq Capital Market.

The Board does not intend for this transaction to be the first step in a series of plans or proposals of a “going private transaction” within the meaning ofRule 13e-3 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”).

Board Discretion to Implement the Reverse Stock Split

If the Board determines to effect the Reverse Stock Split, it will consider certain factors in selecting the specific exchange ratio, including prevailing market conditions, the trading price of the Common Stock and the steps that we will need to take in order to achieve compliance with the bid price requirement and other listing regulations of the Nasdaq Capital Market. Based in part on the price of the Common Stock on the days leading up to the filing of the certificate of amendment to the Restated Certificate of Incorporation effecting the Reverse Stock Split, the Board will determine the ratio of the Reverse Stock Split, in the range of1-for-3 to1-for-20, inclusive, that, in the judgment of the Board, is the reverse split ratio most likely to allow us to achieve and maintain compliance with the minimum $1.00 per share requirement for listing on the Nasdaq Capital Market for the longest period of time, while retaining a sufficient number of outstanding, tradeable shares to facilitate an adequate market.

Notwithstanding approval of the Reverse Stock Split by the stockholders, the Board may, in its sole discretion, abandon all of the proposed certificates of amendment and determine prior to the effectiveness of any filing with the Secretary of State of the State of Delaware not to effect the Reverse Stock Split prior to the one year anniversary of this Special Meeting of stockholders, as permitted under Section 242(c) of the DGCL. If the Board fails to implement any of the certificates of amendment prior to the one year anniversary of this meeting of stockholders, stockholder approval would again be required prior to implementing any Reverse Stock Split.

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Consequences if Stockholder Approval for Proposal Is Not Obtained

If stockholder approval for Proposal No. 1 is not obtained, we will not be able to file a certificate of amendment to the Restated Certificate of Incorporation to effect the Reverse Stock Split. Unless the bid price for the Common Stock increases to greater than $1.00 for ten consecutive business days prior to October 8, 2018, then we will not meet the listing requirements for the Nasdaq Capital Market. If compliance is not achieved by October 8, 2018, and Nasdaq does not grant us an additional 180 day extension, then our stock would be delisted from the Nasdaq Capital Market. If we were unable to qualify for the additional compliance period, or if we were unable to regain compliance during any such period, the Common Stock would likely be transferred to the OTC Bulletin Board or OTC Market.

If we fail to meet all applicable Nasdaq Capital Requirements and Nasdaq determines to delist the Common Stock, the delisting could adversely affect the market liquidity of the Common Stock and the market price of the Common Stock could decrease. Delisting could also adversely affect our ability to obtain financing for the continuation of our operations and/or result in the loss of confidence by investors, suppliers, commercial partners and employees. In addition, the limited number of authorized shares of the Common Stock that are neither outstanding nor reserved for issuance could adversely affect the ability of us to raise capital through equity financings.

Effects of the Reverse Stock Split

The following table sets forth the number of shares of our Common Stock that would be outstanding immediately after the Reverse Stock Split at various exchange ratios, based on the 13,923,825 shares of Common Stock outstanding as of June 30, 2018. The table does not account for fractional shares that will be paid in cash.

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If a stockholder owns 10,000 shares of Common Stock prior to the Reverse Stock Split, after the Reverse Stock Split that same stockholder would own 3,333 shares in the case of a Reverse Stock Split at the ratio of1-for-3, 2,500 shares in the case of a Reverse Stock Split at the ratio of1-for-4, 2,000 shares in the case of a Reverse Stock Split at the ratio of1-for-5, 1,666 shares in the case of a Reverse Stock Split at the ratio of1-for-6, 1,428 shares in the case of a Reverse Stock Split at the ratio of1-for-7, 1,250 shares in the case of a Reverse Stock Split at the ratio of1-for-8, 1,111 shares in the case of a Reverse Stock Split at the ratio of1-for-9, 1,000 shares in the case of a Reverse Stock Split at the ratio of1-for-10, 909 shares in the case of a Reverse Stock Split at the ratio of1-for-11, 833 shares in the case of a Reverse Stock Split at the ratio of1-for-12, 769 shares in the case of a Reverse Stock Split at the ratio of1-for-13, 714 shares in the case of a Reverse Stock Split at the ratio of1-for-14, 666 shares in the case of a Reverse Stock Split at the ratio of1-for-15, 625 shares in the case of a Reverse Stock Split at the ratio of1-for-16, 588 shares in the case of a Reverse Stock Split at the ratio of1-for-17, 555 shares in the case of a Reverse Stock Split at the ratio of1-for-18, 526 shares in the case of a Reverse Stock Split at the ratio of1-for-19, and 500 shares in the case of a Reverse Stock Split at the ratio of1-for-20.

The lasting effect of the proposed Reverse Stock Split upon the market price for our Common Stock cannot be predicted, and the history of similar reverse stock splits for companies in like circumstances is varied. We cannot assure you that the market price per new share of our Common Stock after the Reverse Stock Split (which we refer to as “New Shares”) will rise in proportion to the reduction in the number of old shares of our Common Stock outstanding (which we refer to as “Old Shares”) as a result of the Reverse Stock Split. We also cannot assure you that the market price per New Share will either exceed or remain in excess of the $1.00 minimum bid price as required by the Nasdaq Capital Requirements, or that we will otherwise continue to meet the Nasdaq Capital Requirement, including, for example, the applicable minimum Market Value (as defined in Nasdaq Rule 5005) of Listed Securities (as defined in Nasdaq Rule 5005) requirements. For instance, in 2015 and 2013 we executed a reverse split of our Common Stock in order to maintain compliance with the Nasdaq Capital Requirements. We cannot assure you that another reverse split of our Common Stock will not be necessary in the future. The market price of our Common Stock is dependent on our financial condition, performance, prospects and a number of other factors, many of which are unrelated to the number of shares outstanding. If our efforts to meet the Nasdaq Capital Requirements are unsuccessful, our Common Stock would remain subject to delisting.

The liquidity of our Common Stock could be adversely affected by the reduced number of shares that would be outstanding after the Reverse Stock Split, and the reduced number of shares may make it more difficult to trade shares of the Common Stock. In addition, the Reverse Stock Split will increase the number of our stockholders who own odd lots (less than 100 shares). Stockholders who hold odd lots typically will experience an increase in the cost of selling their shares, as well as possible greater difficulty in effecting those sales.

The Reverse Stock Split will affect all of our holders of Common Stock uniformly and will not affect any stockholder’s percentage ownership interests in the Company or proportionate voting power, except to the extent that the Reverse Stock Split results in any of our stockholders owning a fractional share, in which case such stockholders will receive a cash payment in lieu of such fractional share. The Company’s issued Common Stock will remain fully paid andnon-assessable.

The Reverse Stock Split will not affect the par value of our Common Stock. As a result, upon the effectiveness of the Reverse Stock Split, the stated capital on our balance sheet attributable to our Common Stock will be reduced proportionately based on the exchange ratio selected by the Board for the Reverse Stock Split, and the additionalpaid-in capital account will be credited with the amount by which the stated capital is reduced. The per share net income or loss and net book value of our Common Stock will be increased because there will be fewer shares of our Common Stock outstanding. In addition, proportionate adjustments will be made to the per share exercise price and the number of shares issuable upon the exercise or settlement of all outstanding options, restricted stock units and warrants to purchase or acquire, as applicable, shares of Common Stock of the Company, and the number of shares reserved for issuance pursuant to our existing equity incentive, stock option and employee stock purchase plans will be reduced proportionately based on the exchange ratio selected by the Board for the Reverse Stock Split.

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The Reverse Stock Split will have no effect on the total number of shares of Common Stock we are authorized to issue under the Restated Certificate of Incorporation. Therefore, upon effectiveness of the Reverse Stock Split, the number of shares of Common Stock that are authorized and unissued will increase relative to the number of issued and outstanding shares. We may use the additional authorized and unissued shares of our Common Stock resulting from the Reverse Stock Split to issue additional shares of our Common Stock from time to time in equity financings, under our equity compensation plans or in connection with other matters. The Board currently has no plans, arrangements or understandings regarding the issuance of such additional authorized and unissued shares of the Company’s Common Stock.

Our Common Stock is currently registered under Section 12(b) of the Exchange Act, and we are subject to the periodic reporting and other requirements of the Exchange Act. The proposed Reverse Stock Split will not affect the registration of the Common Stock under the Exchange Act. If the proposed Reverse Stock Split is implemented, the Common Stock will continue to be reported on the Nasdaq Capital Market under the symbol “ABIO.”

Potential Anti-Takeover Effect of the Reverse Stock Split

Upon effectiveness of the Reverse Stock Split, the number of authorized shares of Common Stock that are not issued or outstanding will increase relative to the number of shares of Common Stock that are issued and outstanding prior to the Reverse Stock Split. Although this increase could, under certain circumstances, have an anti-takeover effect (for example, by permitting issuances that would dilute the stock ownership of a person seeking to effect a change in the composition of the Board or contemplating a tender offer or other transaction for the combination of the Company with another company), Proposal No. 1 is not being proposed in response to any effort of which we are aware to accumulate shares of our Common Stock or to obtain control of the Company.

Effective Date

The Reverse Stock Split will be effected at 5:01 p.m. Eastern time, on the date that the certificate of amendment to the Restated Certificate of Incorporation is filed with the Secretary of State of the State of Delaware. Beginning at the effective time of the Reverse Stock Split, each certificate representing Old Shares will be deemed for all corporate purposes to represent New Shares. The texts of the proposed certificates of amendment to the Restated Certificate of Incorporation are in the forms annexed to this proxy statement asAnnexes A-1 throughA-18.

Exchange of Stock Certificates

The transfer agent for the Company will act as the “exchange agent” for purposes of implementing the exchange of stock certificates. Holders of Old Shares will be asked to surrender to the exchange agent certificates representing Old Shares in exchange for certificates representing New Shares in accordance with the procedures to be set forth in a letter of transmittal to be sent by the exchange agent. No new certificates will be issued to a stockholder until the stockholder has surrendered the stockholder’s outstanding certificate(s) together with the properly completed and executed letter of transmittal to the exchange agent. Stockholders should not destroy any stock certificates and should not submit any certificates until requested to do so.

Fractional Shares

No fractional shares of Common Stock will be issued as a result of the proposed Reverse Stock Split. Instead, stockholders who otherwise would be entitled to receive fractional shares will, upon surrender to the exchange agent of certificates representing their fractional shares, be entitled to receive cash in an amount equal to the product obtained by multiplying (i) the closing sales price of our Common Stock as reported on the Nasdaq Capital Market on the effective date of the certificate of amendment to the Restated Certificate of Incorporation by (ii) the number of shares of our Common Stock held by such stockholder before the Reverse Stock Split that would otherwise have been exchanged for such fractional share interest. Holders of as many as nineteen shares (if we were to implement a1-for-20 Reverse Stock Split) of our Common Stock would be eliminated as a result of the cash payment in lieu of any issuance of fractional shares or interests in connection with the Reverse Stock Split. The exact number by which the number of

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holders of our Common Stock would be reduced will depend on the Reverse Stock Split ratio adopted and the number of stockholders that hold less than the Reverse Stock Split ratio as of the effective date of the Reverse Stock Split. As of the Record Date, there were approximately         holders of record of our Common Stock, of which                 were holders of less than 20 shares of our Common Stock. As a result of the Reverse Stock Split, assuming the maximum Reverse Stock Split ratio of1-for-20 were selected, we estimate that cashing out fractional stockholders would potentially reduce that number of stockholders of record to         .

Federal Income Tax Consequences of the Reverse Stock Split

The following is a summary of certain material federal income tax consequences of the Reverse Stock Split to certain holders of Old Shares, but does not purport to be a complete discussion of all of the potential tax considerations relating thereto. This summary is based on the provisions of the United States federal income tax law (including the Internal Revenue Code of 1986, as amended (the “Code”), Treasury Regulations promulgated thereunder, and judicial and administrative interpretations thereof) as of the date hereof, all of which are subject to change retroactively as well as prospectively. Our views regarding the tax consequences of the Reverse Stock Split are not binding upon the Internal Revenue Service or the courts, and there can be no assurance that the Internal Revenue Service or the courts will accept the positions expressed below. This summary assumes that the Old Shares were, and the New Shares will be, held as a “capital asset,” as defined in the Code (i.e., generally, property held for investment). Further, it does not discuss any state, local, foreign or other tax consequences. In addition, this summary does not address the tax consequences applicable to a holder’s particular circumstances or to holders that are subject to special tax rules, including without limitation banks, insurance companies, regulated investment companies, personal holding companies, foreign entities, nonresident alien individuals, broker-dealers, traders,tax-exempt entities and persons who hold Old Shares as a position in a hedging transaction, “straddle,” “conversion transaction” or other risk reduction transaction. THIS SUMMARY OF CERTAIN MATERIAL U.S. FEDERAL TAX CONSIDERATIONS IS FOR GENERAL INFORMATION ONLY AND IS NOT TAX ADVICE. EACH STOCKHOLDER IS URGED TO CONSULT WITH SUCH STOCKHOLDER’S OWN TAX ADVISOR WITH RESPECT TO THE TAX CONSEQUENCES OF THE REVERSE STOCK SPLIT.

Other than the cash payments, if any, received by a stockholder in lieu of fractional shares as discussed below, no gain or loss should be recognized by a stockholder upon such stockholder’s exchange of Old Shares for New Shares pursuant to the Reverse Stock Split. The aggregate tax basis of the New Shares received pursuant to the Reverse Stock Split will be the same as the stockholder’s aggregate tax basis in the Old Shares exchanged therefor, less any basis attributable to fractional share interests. Stockholders who receive cash in lieu of fractional share interests in the New Shares as a result of the Reverse Stock Split will be treated as having received the fractional shares pursuant to the Reverse Stock Split and then as having exchanged the fractional shares for cash in a redemption by the Company, and will generally recognize gain or loss equal to the difference between the amount of cash received in lieu of a fractional share and their adjusted basis allocable to the fractional share interests redeemed. Such gain or loss will be long term capital gain or loss if the Old Shares were held for more than one year. The stockholder’s holding period for the New Shares will include the period during which the stockholder held the Old Shares surrendered in the Reverse Stock Split.

No gain or loss will be recognized by us as a result of the Reverse Stock Split.

No Dissenters’ Rights

Under applicable Delaware law, the Company’s stockholders are not entitled to dissenters’ or appraisal rights with respect to the proposed amendment to the Restated Certificate of Incorporation to effect the Reverse Stock Split. We will not independently provide our stockholders with any such right.

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Vote Required

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 KPMG. Broker non-votes are counted towards a quorum, but are not counted for any purpose in determining whether this matter has been approved.

Principal Accountant Fees and Services

The following table represents aggregate fees billed, or expected to be billed, to us for the fiscal years ended December 31, 2018 and December 31, 2017, by KPMG LLP, our independent registered public accounting firm.

All fees described above were approved by the Audit Committee.

Pre-Approval Policies and Procedures

The above services performed by the independent registered public accounting firm were pre-approved in accordance with the pre-approval policy and procedures adopted by the Audit Committee. This policy describes the permitted audit, audit-related, tax, and other services that our independent registered public accounting firm may perform. The policy also requires that our independent registered public accounting firm provide in writing:

The services expected to be performed by our independent registered public accounting firm during the subsequent fiscal year are presented to the Audit Committee for pre-approval. Any pre-approval must describe, in writing, the particular service or category of services.

Requests for audit, audit-related, tax, and other services not contemplated by those pre-approved services must be submitted to the Audit Committee for specific pre-approval. Generally, pre-approval is considered at the Audit Committee’s regularly scheduled meetings. However, the authority to grant specific pre-approval between meetings, as necessary, has been delegated to the chairman of the Audit Committee. If the chairman is not available, the other two Audit Committee members together have the authority to grant specific pre-approval between meetings. The chairman or the other members must update the Audit Committee at the next regularly scheduled meeting of any services that were granted specific pre-approval.

The Audit Committee pre-approved all audit related services rendered in 2018 and did not rely on the waiver of pre-approval requirement provided by paragraph (c)(7)(i)(C) of Rule 2-01 of Regulation S-X promulgated under the Exchange Act.

The Board Of Directors Recommends

A Vote In Favor Of Proposal 2.

Proposal 3

Advisory Vote on Executive Compensation

Under the Dodd-Frank Wall Street Reform and Consumer Protection Act (the “Dodd-Frank Act”), and Section 14A of the Exchange Act, the Company’s stockholders are entitled to vote to approve, on an advisory basis, the compensation of the Named Executive Officers as disclosed in this proxy statement in accordance with SEC rules. This vote is not intended to address any specific item of compensation, but rather the overall compensation of the Named Executive Officers and the philosophy, policies and practices described in this proxy statement.

At the 2013 annual meeting of stockholders, the stockholders indicated their preference that the Company solicit a non-binding advisory vote on the compensation of the Named Executive Officers, commonly referred to as a “say-on-pay vote,” every three years. The Board of Directors has adopted a policy that is consistent with that preference.

The Company has designed its executive compensation program to attract, motivate, reward and retain the senior management talent required to achieve our corporate objectives and to increase long-term stockholder value.

The compensation of the Named Executive Officers subject to the vote is disclosed in the Executive Compensation discussion below, the compensation tables, and the related narrative disclosure contained in this proxy statement.

Accordingly, the Board of Directors is asking the stockholders to indicate their support for the compensation of the Named Executive Officers as described in this proxy statement by casting a non-binding advisory vote “FOR” the following resolution:

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

This vote is advisory, it is not binding on the Board of Directors. Nevertheless, the views expressed by the stockholders, whether through this vote or otherwise, are important to management and the Board of Directors and, accordingly, the Board of Directors and the Compensation Committee intend to consider the results of this vote in making determinations in the future regarding executive compensation arrangements.

Advisory approval of this proposal requires the 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. Unless the Board of Directors decides to modify its policy regarding the frequency of soliciting say-on-pay votes, the next scheduled say-on-pay vote will be at the 2022 annual meeting of stockholders.

The Board Of Directors Unanimously Recommends

A Vote In Favor Of Proposal 3

Proposal4

Advisory Vote on the Frequency of Solicitation of
the Advisory Vote on Executive Compensation

The Dodd-Frank Act and Section 14A of the Exchange Act enable the Company’s stockholders to indicate their preference regarding how frequently the Company should solicit a non-binding advisory vote on the compensation of the Company’s Common Stocknamed executive officers as disclosed in the Company’s proxy statements. Currently, consistent with the preference expressed by the stockholders at the Company’s 2013 annual meeting of stockholders, the policy of the Board of Directors is to solicit a say-on-pay vote every three years. Accordingly, the Company is asking stockholders to indicate whether they would prefer an advisory vote every year, every other year or every three years or abstaining from voting.

After considering the benefits and consequences of each alternative, the Board of Directors recommends that the advisory vote on the record datecompensation of the Company’s named executive officers be submitted to the stockholders every year.

The Board of Directors believes that an annual advisory vote on the compensation of the Company’s named executive officers is requiredmost consistent with its approach to compensation. These reasons include our beliefs that:

The Board of Directors intends that the compensation program be responsive to stockholder concerns, and believes that annual advisory votes best facilitates this.

Accordingly, the Board of Directors is asking stockholders to indicate their preferred voting frequency by voting for one, two or three years or abstaining from voting on the resolution below:

“RESOLVED, that the alternative of soliciting advisory stockholder approval of the proposed certificatescompensation of amendment to the Restated CertificateCompany’s named executive officers once every one, two or three calendar years that receives the highest number of Incorporation set forthvotes from the holders of shares present in Proposal No. 1person or represented by proxy and included as AnnexesA-1 throughA-18. Brokernon-votes with respect to Proposal No. 1 will be treated as votes “against” the proposal because they represent shares entitled to vote at the annual meeting shall be considered the frequency preferred by the stockholders.”

While the Board of Directors believes that haveits recommendation is appropriate at this time, the stockholders are not been votedvoting to approve or disapprove that recommendation, but are instead asked to indicate their preferences, on an advisory basis, as to whether the non-binding advisory vote on the approval of the Company’s executive officer compensation practices should be held every year, every other year or every three years. The option among those choices that receives the highest number of votes from the holders of shares present in the affirmative. Abstentions will also have the same effect as votes “against” the proposal because they represent sharesperson or represented by proxy and entitled to vote that have not been votedat the annual meeting will be deemed to be the frequency preferred by the stockholders.

The Board of Directors and the Compensation Committee value the opinions of the stockholders in this matter, and the Board of Directors intends to hold say-on-pay votes in the affirmative.future in accordance with the alternative that receives the most stockholder support, even if that alternative does not receive the support of a majority of the shares present and entitled to vote.

THE BOARD UNANIMOUSLY RECOMMENDS The Board Of Directors Unanimously Recommends

A VOTE “FOR” THIS PROPOSALVote In Favor Of “Every Year” on Proposal 4

SECURITY OWNERSHIP OF

CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

13

SECURITY OWNERSHIPOF

CERTAIN BENEFICIAL OWNERSAND MANAGEMENT

Principal Stockholders

The following table sets forth certain information regarding the ownership of the Company’s Common Stock as of the August 31, 2018,record date, October 14, 2019, by: (i) each director and nominee for director, (ii) each of our named executive officers, (iii) all executive officers and directors of the Company as a group and (iv) all those known by the Company to be beneficial owners of more than five percent of its Common Stock.Stock, if any. Unless otherwise noted below, the address of each beneficial owner listed on the table is c/o ARCA biopharma, Inc., 11080 CirclePoint Road, Suite 140, Westminster, Colorado, 80020.

We have determined beneficial ownership in accordance with the rules of the SEC. Except as indicated by the footnotes below, we believe, based on the information furnished to us, that the persons and entities named in the table below have sole voting and investment power with respect to all shares of Common Stock that they beneficially own, subject to applicable community property laws. The table is based upon information supplied by officers, directors and principal stockholders and Schedules 13G or 13D, Form 4s or other ownership reports filed with the SEC. For purposes of this table, certain of our outstanding warrants that may be exercisable for fractional shares have been rounded down to the nearest whole number.

In computing the number of shares of Common Stock beneficially owned by a person and the percentage ownership of that person, we deemed outstanding shares of Common Stock subject to options, restricted stock units, or warrants held by that person that are currently exercisable or exercisable within 60 days of August 31, 2018.October 14, 2019. We did not deem these shares outstanding, however, for the purpose of computing the percentage ownership of any other person.

The percentages below are based on 13,923,8251,594,070 shares of our Common Stock outstanding as of August 31, 2018.October 14, 2019.

HOUSEHOLDINGOF PROXY MATERIALSCertain Transactions With or Involving Related Persons

The following is a summary of transactions since January 1, 2017, to which we have been a party in which the amount involved exceeded the lesser of $120,000 or one percent of the average of our total assets at fiscal yearend for 2017 and 2018, and in which any of our executive officers, directors or holders of more than 5% of our capital stock, or any member of the immediate family of any of the foregoing persons, had or will have a direct or indirect material interest, other than compensation arrangements disclosed above under the heading “Executive Compensation”.

Transactions With the Company’s President and Chief Executive Officer

The Company has entered into unrestricted research grants with the academic research laboratory of Dr. Bristow, the Company’s President and Chief Executive Officer, at the University of Colorado. Funding of any unrestricted research grants is contingent upon the Company’s financial condition, and can be deferred or terminated at the Company’s discretion. Total expense under these arrangements for the six months ended June 30, 2019 and the years ended December 31, 2018 and 2017 was approximately $141,000, $325,000 and $418,000, respectively, of which $111,000 was unpaid and included in Accrued expenses and other liabilities as of December 31, 2018 in the financial statements included in our Annual Report on Form 10-K filed with the SEC on February 27, 2019.

Policies and Procedures for Related Party Transactions

In accordance with its charter, our Audit Committee reviews and approves all related party transactions. This review covers any material transaction, arrangement or relationship, or any series of similar transactions, arrangements or relationships, in which we were or are to be a participant, and a related party had or will have a direct or indirect material interest, including, purchases of goods or services by or from the related party or entities in which the related party has a material interest, indebtedness, guarantees of indebtedness and employment by us of a related party. In evaluating any related party transaction, the Audit Committee considers, among other things, the relative benefits of the transaction to the Company, what, if any, alternatives may be available from persons not affiliated to the Company, if the terms of the transaction have been negotiated on an arm’s length basis and any other matters that the Audit Committee may deem relevant in determining whether such related party transaction is in the best interests of the Company and its stockholders.

Householding of Proxy Materials

The SEC has adopted rules that permit companies and intermediaries (e.g., brokers) to satisfy the delivery requirements for the Proxy Materials with respect to two or more stockholders sharing the same address by delivering a single set of the Proxy Materials addressed to those stockholders. This process, which is commonly referred to as “householding,” potentially means extra convenience for stockholders and cost savings for companies.

In connection with the SpecialAnnual Meeting, a number of brokers with account holders who are ARCA stockholders will be “householding” the Proxy Materials. A single set of the Proxy Materials will be delivered to multiple stockholders sharing an address unless contrary instructions have been received from the affected stockholders. Once you have received notice from your broker that they will be “householding” communications to your address, “householding” will continue until you are notified otherwise or until you revoke your consent. If, at any time, you no longer wish to participate in “householding” and would prefer to receive a separate set of the Proxy Materials, please notify your broker or ARCA. Direct your written request to Secretary, ARCA biopharma, Inc., 11080 CirclePoint Road, Suite 140, Westminster, Colorado, 80020 or contact Investor Relations at 720-940-2100720-940-2100.. The Company undertakes to promptly deliver a separate offsetset of the Proxy Materials promptly upon receiving your written request. Stockholders who currently receive multiple copies of the Proxy Materials at their addresses and would like to request “householding” of their communications should contact their brokers.

OTHER MATTERSOther Matters

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

By Order of the Board of Directors

Christopher Ozeroff

Christopher Ozeroff

Secretary, Senior Vice President and General Counsel

October 28, 2018 2019

We will provide without charge to each person, including any beneficial owner of our Common Stock to whom a copy of this proxy statement hasProxy Materials have been delivered, upon written or oral request, a copy of any or all of the documents referred to above that have been or may be incorporated in this proxy statementinto these Proxy Materials by reference.reference, including a copy of our Annual Report on Form 10-K as filed with the SEC on February 27, 2019. Requests for copies should be directed to: Corporate Secretary, ARCA biopharma, Inc., 11080 CirclePoint Road, Suite 140, Westminster, Colorado 80020.80020 or contact Investor Relations at 720‑940‑2100.

16

ANNEXA-1

CERTIFICATE OF AMENDMENT

OF

AMENDEDMMMMMMMMMMMM   MMMMMMMMMMMMMMM C123456789  MMMMMMMMM   000004  ENDORSEMENT_LINE______________ SACKPACK_____________   MR ASAMPLE DESIGNATION (IF ANY) ADD 1 ADD 2 ADD 3 ADD 4 ADD 5 ADD 6  Using a black ink pen, mark your votes with an X as shown in this example. Please do not write outside the designated areas.    000000000.000000 ext 000000000.000000 ext 000000000.000000 ext 000000000.000000 ext 000000000.000000 ext 000000000.000000 ext  Your vote matters – here’s how to vote!  You may vote online or by phone instead of mailing this card.   Votes submitted electronically must be received by 1:00 a.m., Mountain Time, on December 10, 2019.   Online Go to www.investorvote.com/ABIO or scan the QR code — login details are located in the shaded bar below.  Phone  Call toll free 1-800-652-VOTE (8683) within the USA, US territories and Canada  Save paper, time and money! Sign up for electronic delivery at www.investorvote.com/ABIO   • IF VOTING BY MAIL, SIGN, DETACH AND RESTATED CERTIFICATE OF INCORPORATION

OF

ARCA BIOPHARMA, INC.

ARCABIOPHARMA, INC., a corporation organized and existing under and by virtue of the General Corporation Law of the State of Delaware (the “DGCL”), does hereby certify:

FIRST:               The name of the corporation is ARCA biopharma, Inc. (the “Corporation”).

SECOND:           The date of filing of its original Certificate of Incorporation with the Secretary of State of the State of Delaware was March 16, 2004 under the name “Nuvelo Merger Sub, Inc.”

THIRD:RETURN THE BOTTOM PORTION IN THE ENCLOSED ENVELOPE. •   Proposals — The Board of Directors (the “Board”)recommend a vote FOR all the nominees listed, FOR Proposals 2-3 and ONE YEAR for Proposal 4.  1. Election of Directors:  + For Withhold For Withhold  01 – Dr. Linda Grais   02 – Dr. Anders Hove   For  Against Abstain  For  Against Abstain   2. To ratify the selection by the Audit Committee of the Corporation, actingBoard of  3. To approve, on an advisory basis, the compensation of the   Directors of KPMG LLP as independent registered public  Company’s named executive officers, as disclosed in accordancethe   accounting firm of the Company for its fiscal year ending  proxy statement.   December 31, 2019.   1 Year  2 Years 3 Years Abstain   4. To indicate, on an advisory basis, the preferred   frequency of stockholder advisory votes on the   compensation of the Company’s named   executive officers.     Please sign exactly as name(s) appears hereon. Joint owners should each sign. When signing as attorney, executor, administrator, corporate officer, trustee, guardian, or custodian, please give full title. Date (mm/dd/yyyy) — Please print date below. Signature 1 — Please keep signature within the box. Signature 2 — Please keep signature within the box.   MR A SAMPLE (THIS AREA IS SET UPTOACCOMMODATE  C 1234567890                  JNT  140 CHARACTERS) MR A SAMPLE AND MR A SAMPLE AND MR ASAMPLE AND MR ASAMPLE AND MR ASAMPLE AND 1UPX 434956 MR ASAMPLE AND MR ASAMPLE AND MR ASAMPLE AND    MMMMMMM +  0351ZB

Small steps make an impact.  Help the environment by consenting to receive electronic delivery, sign up at www.investorvote.com/ABIO    • IF VOTING BY MAIL, SIGN, DETACH AND RETURN THE BOTTOM PORTION IN THE ENCLOSED ENVELOPE. •  Proxy — ARCA biopharma, Inc.  +  Notice of 2019 Annual Meeting of Shareholders Proxy Solicited by Board of Directors for Annual Meeting — December 10, 2019  Michael R. Bristow, Brian L. Selby and Christopher D. Ozeroff (the “Proxies”), or any of them, each with the provisionspower of Sections 141substitution, are hereby authorized to represent and 242 of the DGCL, adopted resolutions amending its Amended and Restated Certificate of Incorporation, as amended, as follows:

1.                         Article IV of the Amended and Restated Certificate of Incorporation of the Corporation is hereby amended to add the following provisions in their entirety to the existing provisions of Article IV:

“Effective at 5:01 p.m. Eastern time, on the date of the filing of this Certificate of Amendment to the Amended and Restated Certificate of Incorporation with the Secretary of State of the State of Delaware (the “Effective Time”),vote the shares of the Corporation’s Common Stock, par value $0.001 per share, issued and outstanding immediately priorundersigned, with all the powers which the undersigned would possess if personally present, at the Annual Meeting of Shareholders of ARCA biopharma, Inc. to be held on December 10, 2019 or at any postponement or adjournment thereof.  Shares represented by this proxy will be voted as directed herein. If no such directions are indicated, the Effective Time andProxies will have authority to vote FOR the shareselection of Common Stock issued and held in the treasury of the Corporation immediately prior to the Effective Time shall be combined into a smaller number of shares such that each 3 shares of issued and outstanding Common Stock immediately prior to the Effective Time are combined into one validly issued, fully paid and nonassessable share of Common Stock, par value $0.001 per share. Notwithstanding the immediately preceding sentence, no fractional shares shall be issued and, in lieu thereof, upon surrender after the Effective Time of a certificate which formerly represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time, any person who would otherwise be entitled to a fractional share of Common Stock as a result of the combination, following the Effective Time (after taking into account all fractional shares of Common Stock otherwise issuable to such holder), shall be entitled to receive a cash payment equal to the fraction to which such holder would otherwise be entitled multiplied by the fair value of the Common Stock on the date of the Effective Time, as determined by the Board of Directors.

Each stock certificate that, immediately priorDirectors and FOR Proposals 2-3 and ONE YEAR for Proposal 4.  In their discretion, the Proxies are authorized to vote upon such other business as may properly come before the Effective Time, represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time shall, from and after the Effective Time, automatically and without the necessity of presenting the same for exchange, represent that number of whole shares of Common Stock after the Effective Time into which the shares of Common Stock formerly represented by such certificate shall have been combined (as well as the right to receive cash in lieu of fractional shares of Common Stock after the Effective Time), provided however, that each person of record holding a certificate that represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time shall receive, upon surrender of such certificate, a new certificate evidencing and representing the number of whole shares of Common Stock after the Effective Time into which the shares of Common Stock formerly represented by such certificate shall have been combined.”

FOURTH:           Thereafter, pursuant to a resolution by the Board, this Certificate of Amendment was submitted to the stockholders of the Corporation for their approval in accordance with the provisions of Section 211 and 242 of the DGCL. Accordingly, said proposed amendment has been adopted in accordance with Section 242 of the DGCL.

IN WITNESS WHEREOF,ARCABIOPHARMA, INC. has caused this Certificate of Amendmentmeeting.  (Items to be signed by its duly authorized officer this ______ dayvoted appear on reverse side)   Change of ________, 2018.Address — Please print new address below. Comments — Please print your comments below.  +  

ANNEXA-2

CERTIFICATE OF AMENDMENT

OF

AMENDED AND RESTATED CERTIFICATE OF INCORPORATION

OF

ARCA BIOPHARMA, INC.

ARCABIOPHARMA, INC., a corporation organized and existing under and by virtue of the General Corporation Law of the State of Delaware (the “DGCL”), does hereby certify:

FIRST:               The name of the corporation is ARCA biopharma, Inc. (the “Corporation”).

SECOND:           The date of filing of its original Certificate of Incorporation with the Secretary of State of the State of Delaware was March 16, 2004 under the name “Nuvelo Merger Sub, Inc.”

THIRD:              The Board of Directors (the “Board”) of the Corporation, acting in accordance with the provisions of Sections 141 and 242 of the DGCL, adopted resolutions amending its Amended and Restated Certificate of Incorporation, as amended, as follows:

1.                         Article IV of the Amended and Restated Certificate of Incorporation of the Corporation is hereby amended to add the following provisions in their entirety to the existing provisions of Article IV:

“Effective at 5:01 p.m. Eastern time, on the date of the filing of this Certificate of Amendment to the Amended and Restated Certificate of Incorporation with the Secretary of State of the State of Delaware (the “Effective Time”), the shares of the Corporation’s Common Stock, par value $0.001 per share, issued and outstanding immediately prior to the Effective Time and the shares of Common Stock issued and held in the treasury of the Corporation immediately prior to the Effective Time shall be combined into a smaller number of shares such that each 4 shares of issued and outstanding Common Stock immediately prior to the Effective Time are combined into one validly issued, fully paid and nonassessable share of Common Stock, par value $0.001 per share. Notwithstanding the immediately preceding sentence, no fractional shares shall be issued and, in lieu thereof, upon surrender after the Effective Time of a certificate which formerly represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time, any person who would otherwise be entitled to a fractional share of Common Stock as a result of the combination, following the Effective Time (after taking into account all fractional shares of Common Stock otherwise issuable to such holder), shall be entitled to receive a cash payment equal to the fraction to which such holder would otherwise be entitled multiplied by the fair value of the Common Stock on the date of the Effective Time, as determined by the Board of Directors.

Each stock certificate that, immediately prior to the Effective Time, represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time shall, from and after the Effective Time, automatically and without the necessity of presenting the same for exchange, represent that number of whole shares of Common Stock after the Effective Time into which the shares of Common Stock formerly represented by such certificate shall have been combined (as well as the right to receive cash in lieu of fractional shares of Common Stock after the Effective Time), provided however, that each person of record holding a certificate that represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time shall receive, upon surrender of such certificate, a new certificate evidencing and representing the number of whole shares of Common Stock after the Effective Time into which the shares of Common Stock formerly represented by such certificate shall have been combined.”

FOURTH:           Thereafter, pursuant to a resolution by the Board, this Certificate of Amendment was submitted to the stockholders of the Corporation for their approval in accordance with the provisions of Section 211 and 242 of the DGCL. Accordingly, said proposed amendment has been adopted in accordance with Section 242 of the DGCL.

IN WITNESS WHEREOF,ARCABIOPHARMA, INC.has caused this Certificate of Amendment to be signed by its duly authorized officer this ______ day of ________, 2018.

ANNEXA-3

CERTIFICATE OF AMENDMENT

OF

AMENDED AND RESTATED CERTIFICATE OF INCORPORATION

OF

ARCA BIOPHARMA, INC.

ARCABIOPHARMA, INC.,a corporation organized and existing under and by virtue of the General Corporation Law of the State of Delaware (the “DGCL”), does hereby certify:

FIRST:               The name of the corporation is ARCA biopharma, Inc. (the “Corporation”).

SECOND:           The date of filing of its original Certificate of Incorporation with the Secretary of State of the State of Delaware was March 16, 2004 under the name “Nuvelo Merger Sub, Inc.”

THIRD:              The Board of Directors (the “Board”) of the Corporation, acting in accordance with the provisions of Sections 141 and 242 of the DGCL, adopted resolutions amending its Amended and Restated Certificate of Incorporation, as amended, as follows:

1.                         Article IV of the Amended and Restated Certificate of Incorporation of the Corporation is hereby amended to add the following provisions in their entirety to the existing provisions of Article IV:

“Effective at 5:01 p.m. Eastern time, on the date of the filing of this Certificate of Amendment to the Amended and Restated Certificate of Incorporation with the Secretary of State of the State of Delaware (the “Effective Time”), the shares of the Corporation’s Common Stock, par value $0.001 per share, issued and outstanding immediately prior to the Effective Time and the shares of Common Stock issued and held in the treasury of the Corporation immediately prior to the Effective Time shall be combined into a smaller number of shares such that each 5 shares of issued and outstanding Common Stock immediately prior to the Effective Time are combined into one validly issued, fully paid and nonassessable share of Common Stock, par value $0.001 per share. Notwithstanding the immediately preceding sentence, no fractional shares shall be issued and, in lieu thereof, upon surrender after the Effective Time of a certificate which formerly represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time, any person who would otherwise be entitled to a fractional share of Common Stock as a result of the combination, following the Effective Time (after taking into account all fractional shares of Common Stock otherwise issuable to such holder), shall be entitled to receive a cash payment equal to the fraction to which such holder would otherwise be entitled multiplied by the fair value of the Common Stock on the date of the Effective Time, as determined by the Board of Directors.

Each stock certificate that, immediately prior to the Effective Time, represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time shall, from and after the Effective Time, automatically and without the necessity of presenting the same for exchange, represent that number of whole shares of Common Stock after the Effective Time into which the shares of Common Stock formerly represented by such certificate shall have been combined (as well as the right to receive cash in lieu of fractional shares of Common Stock after the Effective Time), provided however, that each person of record holding a certificate that represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time shall receive, upon surrender of such certificate, a new certificate evidencing and representing the number of whole shares of Common Stock after the Effective Time into which the shares of Common Stock formerly represented by such certificate shall have been combined.”

FOURTH:           Thereafter, pursuant to a resolution by the Board, this Certificate of Amendment was submitted to the stockholders of the Corporation for their approval in accordance with the provisions of Section 211 and 242 of the DGCL. Accordingly, said proposed amendment has been adopted in accordance with Section 242 of the DGCL.

IN WITNESS WHEREOF,ARCABIOPHARMA, INC. has caused this Certificate of Amendment to be signed by its duly authorized officer this ______ day of ________, 2018.

ANNEXA-4

CERTIFICATE OF AMENDMENT

OF

AMENDED AND RESTATED CERTIFICATE OF INCORPORATION

OF

ARCA BIOPHARMA, INC.

ARCABIOPHARMA, INC., a corporation organized and existing under and by virtue of the General Corporation Law of the State of Delaware (the “DGCL”), does hereby certify:

FIRST:               The name of the corporation is ARCA biopharma, Inc. (the “Corporation”).

SECOND:           The date of filing of its original Certificate of Incorporation with the Secretary of State of the State of Delaware was March 16, 2004 under the name “Nuvelo Merger Sub, Inc.”

THIRD:              The Board of Directors (the “Board”) of the Corporation, acting in accordance with the provisions of Sections 141 and 242 of the DGCL, adopted resolutions amending its Amended and Restated Certificate of Incorporation, as amended, as follows:

1.                         Article IV of the Amended and Restated Certificate of Incorporation of the Corporation is hereby amended to add the following provisions in their entirety to the existing provisions of Article IV:

“Effective at 5:01 p.m. Eastern time, on the date of the filing of this Certificate of Amendment to the Amended and Restated Certificate of Incorporation with the Secretary of State of the State of Delaware (the “Effective Time”), the shares of the Corporation’s Common Stock, par value $0.001 per share, issued and outstanding immediately prior to the Effective Time and the shares of Common Stock issued and held in the treasury of the Corporation immediately prior to the Effective Time shall be combined into a smaller number of shares such that each 6 shares of issued and outstanding Common Stock immediately prior to the Effective Time are combined into one validly issued, fully paid and nonassessable share of Common Stock, par value $0.001 per share. Notwithstanding the immediately preceding sentence, no fractional shares shall be issued and, in lieu thereof, upon surrender after the Effective Time of a certificate which formerly represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time, any person who would otherwise be entitled to a fractional share of Common Stock as a result of the combination, following the Effective Time (after taking into account all fractional shares of Common Stock otherwise issuable to such holder), shall be entitled to receive a cash payment equal to the fraction to which such holder would otherwise be entitled multiplied by the fair value of the Common Stock on the date of the Effective Time, as determined by the Board of Directors.

Each stock certificate that, immediately prior to the Effective Time, represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time shall, from and after the Effective Time, automatically and without the necessity of presenting the same for exchange, represent that number of whole shares of Common Stock after the Effective Time into which the shares of Common Stock formerly represented by such certificate shall have been combined (as well as the right to receive cash in lieu of fractional shares of Common Stock after the Effective Time), provided however, that each person of record holding a certificate that represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time shall receive, upon surrender of such certificate, a new certificate evidencing and representing the number of whole shares of Common Stock after the Effective Time into which the shares of Common Stock formerly represented by such certificate shall have been combined.”

FOURTH:           Thereafter, pursuant to a resolution by the Board, this Certificate of Amendment was submitted to the stockholders of the Corporation for their approval in accordance with the provisions of Section 211 and 242 of the DGCL. Accordingly, said proposed amendment has been adopted in accordance with Section 242 of the DGCL.

IN WITNESS WHEREOF,ARCABIOPHARMA, INC. has caused this Certificate of Amendment to be signed by its duly authorized officer this ______ day of ________, 2018.

ANNEXA-5

CERTIFICATE OF AMENDMENT

OF

AMENDED AND RESTATED CERTIFICATE OF INCORPORATION

OF

ARCA BIOPHARMA, INC.

ARCABIOPHARMA, INC., a corporation organized and existing under and by virtue of the General Corporation Law of the State of Delaware (the “DGCL”), does hereby certify:

FIRST:               The name of the corporation is ARCA biopharma, Inc. (the “Corporation”).

SECOND:           The date of filing of its original Certificate of Incorporation with the Secretary of State of the State of Delaware was March 16, 2004 under the name “Nuvelo Merger Sub, Inc.”

THIRD:              The Board of Directors (the “Board”) of the Corporation, acting in accordance with the provisions of Sections 141 and 242 of the DGCL, adopted resolutions amending its Amended and Restated Certificate of Incorporation, as amended, as follows:

1.                         Article IV of the Amended and Restated Certificate of Incorporation of the Corporation is hereby amended to add the following provisions in their entirety to the existing provisions of Article IV:

“Effective at 5:01 p.m. Eastern time, on the date of the filing of this Certificate of Amendment to the Amended and Restated Certificate of Incorporation with the Secretary of State of the State of Delaware (the “Effective Time”), the shares of the Corporation’s Common Stock, par value $0.001 per share, issued and outstanding immediately prior to the Effective Time and the shares of Common Stock issued and held in the treasury of the Corporation immediately prior to the Effective Time shall be combined into a smaller number of shares such that each 7 shares of issued and outstanding Common Stock immediately prior to the Effective Time are combined into one validly issued, fully paid and nonassessable share of Common Stock, par value $0.001 per share. Notwithstanding the immediately preceding sentence, no fractional shares shall be issued and, in lieu thereof, upon surrender after the Effective Time of a certificate which formerly represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time, any person who would otherwise be entitled to a fractional share of Common Stock as a result of the combination, following the Effective Time (after taking into account all fractional shares of Common Stock otherwise issuable to such holder), shall be entitled to receive a cash payment equal to the fraction to which such holder would otherwise be entitled multiplied by the fair value of the Common Stock on the date of the Effective Time, as determined by the Board of Directors.

Each stock certificate that, immediately prior to the Effective Time, represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time shall, from and after the Effective Time, automatically and without the necessity of presenting the same for exchange, represent that number of whole shares of Common Stock after the Effective Time into which the shares of Common Stock formerly represented by such certificate shall have been combined (as well as the right to receive cash in lieu of fractional shares of Common Stock after the Effective Time), provided however, that each person of record holding a certificate that represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time shall receive, upon surrender of such certificate, a new certificate evidencing and representing the number of whole shares of Common Stock after the Effective Time into which the shares of Common Stock formerly represented by such certificate shall have been combined.”

FOURTH:           Thereafter, pursuant to a resolution by the Board, this Certificate of Amendment was submitted to the stockholders of the Corporation for their approval in accordance with the provisions of Section 211 and 242 of the DGCL. Accordingly, said proposed amendment has been adopted in accordance with Section 242 of the DGCL.

IN WITNESS WHEREOF,ARCABIOPHARMA, INC. has caused this Certificate of Amendment to be signed by its duly authorized officer this ______ day of ________, 2018.

ANNEXA-6

CERTIFICATE OF AMENDMENT

OF

AMENDED AND RESTATED CERTIFICATE OF INCORPORATION

OF

ARCA BIOPHARMA, INC.

ARCABIOPHARMA, INC., a corporation organized and existing under and by virtue of the General Corporation Law of the State of Delaware (the “DGCL”), does hereby certify:

FIRST:               The name of the corporation is ARCA biopharma, Inc. (the “Corporation”).

SECOND:           The date of filing of its original Certificate of Incorporation with the Secretary of State of the State of Delaware was March 16, 2004 under the name “Nuvelo Merger Sub, Inc.”

THIRD:              The Board of Directors (the “Board”) of the Corporation, acting in accordance with the provisions of Sections 141 and 242 of the DGCL, adopted resolutions amending its Amended and Restated Certificate of Incorporation, as amended, as follows:

1.                         Article IV of the Amended and Restated Certificate of Incorporation of the Corporation is hereby amended to add the following provisions in their entirety to the existing provisions of Article IV:

“Effective at 5:01 p.m. Eastern time, on the date of the filing of this Certificate of Amendment to the Amended and Restated Certificate of Incorporation with the Secretary of State of the State of Delaware (the “Effective Time”), the shares of the Corporation’s Common Stock, par value $0.001 per share, issued and outstanding immediately prior to the Effective Time and the shares of Common Stock issued and held in the treasury of the Corporation immediately prior to the Effective Time shall be combined into a smaller number of shares such that each 8 shares of issued and outstanding Common Stock immediately prior to the Effective Time are combined into one validly issued, fully paid and nonassessable share of Common Stock, par value $0.001 per share. Notwithstanding the immediately preceding sentence, no fractional shares shall be issued and, in lieu thereof, upon surrender after the Effective Time of a certificate which formerly represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time, any person who would otherwise be entitled to a fractional share of Common Stock as a result of the combination, following the Effective Time (after taking into account all fractional shares of Common Stock otherwise issuable to such holder), shall be entitled to receive a cash payment equal to the fraction to which such holder would otherwise be entitled multiplied by the fair value of the Common Stock on the date of the Effective Time, as determined by the Board of Directors.

Each stock certificate that, immediately prior to the Effective Time, represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time shall, from and after the Effective Time, automatically and without the necessity of presenting the same for exchange, represent that number of whole shares of Common Stock after the Effective Time into which the shares of Common Stock formerly represented by such certificate shall have been combined (as well as the right to receive cash in lieu of fractional shares of Common Stock after the Effective Time), provided however, that each person of record holding a certificate that represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time shall receive, upon surrender of such certificate, a new certificate evidencing and representing the number of whole shares of Common Stock after the Effective Time into which the shares of Common Stock formerly represented by such certificate shall have been combined.”

FOURTH:           Thereafter, pursuant to a resolution by the Board, this Certificate of Amendment was submitted to the stockholders of the Corporation for their approval in accordance with the provisions of Section 211 and 242 of the DGCL. Accordingly, said proposed amendment has been adopted in accordance with Section 242 of the DGCL.

IN WITNESS WHEREOF,ARCABIOPHARMA, INC. has caused this Certificate of Amendment to be signed by its duly authorized officer this ______ day of ________, 2018.

ANNEXA-7

CERTIFICATE OF AMENDMENT

OF

AMENDED AND RESTATED CERTIFICATE OF INCORPORATION

OF

ARCA BIOPHARMA, INC.

ARCABIOPHARMA, INC., a corporation organized and existing under and by virtue of the General Corporation Law of the State of Delaware (the “DGCL”), does hereby certify:

FIRST:               The name of the corporation is ARCA biopharma, Inc. (the “Corporation”).

SECOND:           The date of filing of its original Certificate of Incorporation with the Secretary of State of the State of Delaware was March 16, 2004 under the name “Nuvelo Merger Sub, Inc.”

THIRD:              The Board of Directors (the “Board”) of the Corporation, acting in accordance with the provisions of Sections 141 and 242 of the DGCL, adopted resolutions amending its Amended and Restated Certificate of Incorporation, as amended, as follows:

1.                         Article IV of the Amended and Restated Certificate of Incorporation of the Corporation is hereby amended to add the following provisions in their entirety to the existing provisions of Article IV:

“Effective at 5:01 p.m. Eastern time, on the date of the filing of this Certificate of Amendment to the Amended and Restated Certificate of Incorporation with the Secretary of State of the State of Delaware (the “Effective Time”), the shares of the Corporation’s Common Stock, par value $0.001 per share, issued and outstanding immediately prior to the Effective Time and the shares of Common Stock issued and held in the treasury of the Corporation immediately prior to the Effective Time shall be combined into a smaller number of shares such that each 9 shares of issued and outstanding Common Stock immediately prior to the Effective Time are combined into one validly issued, fully paid and nonassessable share of Common Stock, par value $0.001 per share. Notwithstanding the immediately preceding sentence, no fractional shares shall be issued and, in lieu thereof, upon surrender after the Effective Time of a certificate which formerly represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time, any person who would otherwise be entitled to a fractional share of Common Stock as a result of the combination, following the Effective Time (after taking into account all fractional shares of Common Stock otherwise issuable to such holder), shall be entitled to receive a cash payment equal to the fraction to which such holder would otherwise be entitled multiplied by the fair value of the Common Stock on the date of the Effective Time, as determined by the Board of Directors.

Each stock certificate that, immediately prior to the Effective Time, represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time shall, from and after the Effective Time, automatically and without the necessity of presenting the same for exchange, represent that number of whole shares of Common Stock after the Effective Time into which the shares of Common Stock formerly represented by such certificate shall have been combined (as well as the right to receive cash in lieu of fractional shares of Common Stock after the Effective Time), provided however, that each person of record holding a certificate that represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time shall receive, upon surrender of such certificate, a new certificate evidencing and representing the number of whole shares of Common Stock after the Effective Time into which the shares of Common Stock formerly represented by such certificate shall have been combined.”

FOURTH:           Thereafter, pursuant to a resolution by the Board, this Certificate of Amendment was submitted to the stockholders of the Corporation for their approval in accordance with the provisions of Section 211 and 242 of the DGCL. Accordingly, said proposed amendment has been adopted in accordance with Section 242 of the DGCL.

IN WITNESS WHEREOF,ARCABIOPHARMA, INC. has caused this Certificate of Amendment to be signed by its duly authorized officer this ______ day of ________, 2018.

ANNEXA-8

CERTIFICATE OF AMENDMENT

OF

AMENDED AND RESTATED CERTIFICATE OF INCORPORATION

OF

ARCA BIOPHARMA, INC.

ARCABIOPHARMA, INC., a corporation organized and existing under and by virtue of the General Corporation Law of the State of Delaware (the “DGCL”), does hereby certify:

FIRST:               The name of the corporation is ARCA biopharma, Inc. (the “Corporation”).

SECOND:           The date of filing of its original Certificate of Incorporation with the Secretary of State of the State of Delaware was March 16, 2004 under the name “Nuvelo Merger Sub, Inc.”

THIRD:              The Board of Directors (the “Board”) of the Corporation, acting in accordance with the provisions of Sections 141 and 242 of the DGCL, adopted resolutions amending its Amended and Restated Certificate of Incorporation, as amended, as follows:

1.                         Article IV of the Amended and Restated Certificate of Incorporation of the Corporation is hereby amended to add the following provisions in their entirety to the existing provisions of Article IV:

“Effective at 5:01 p.m. Eastern time, on the date of the filing of this Certificate of Amendment to the Amended and Restated Certificate of Incorporation with the Secretary of State of the State of Delaware (the “Effective Time”), the shares of the Corporation’s Common Stock, par value $0.001 per share, issued and outstanding immediately prior to the Effective Time and the shares of Common Stock issued and held in the treasury of the Corporation immediately prior to the Effective Time shall be combined into a smaller number of shares such that each 10 shares of issued and outstanding Common Stock immediately prior to the Effective Time are combined into one validly issued, fully paid and nonassessable share of Common Stock, par value $0.001 per share. Notwithstanding the immediately preceding sentence, no fractional shares shall be issued and, in lieu thereof, upon surrender after the Effective Time of a certificate which formerly represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time, any person who would otherwise be entitled to a fractional share of Common Stock as a result of the combination, following the Effective Time (after taking into account all fractional shares of Common Stock otherwise issuable to such holder), shall be entitled to receive a cash payment equal to the fraction to which such holder would otherwise be entitled multiplied by the fair value of the Common Stock on the date of the Effective Time, as determined by the Board of Directors.

Each stock certificate that, immediately prior to the Effective Time, represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time shall, from and after the Effective Time, automatically and without the necessity of presenting the same for exchange, represent that number of whole shares of Common Stock after the Effective Time into which the shares of Common Stock formerly represented by such certificate shall have been combined (as well as the right to receive cash in lieu of fractional shares of Common Stock after the Effective Time), provided however, that each person of record holding a certificate that represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time shall receive, upon surrender of such certificate, a new certificate evidencing and representing the number of whole shares of Common Stock after the Effective Time into which the shares of Common Stock formerly represented by such certificate shall have been combined.”

FOURTH:           Thereafter, pursuant to a resolution by the Board, this Certificate of Amendment was submitted to the stockholders of the Corporation for their approval in accordance with the provisions of Section 211 and 242 of the DGCL. Accordingly, said proposed amendment has been adopted in accordance with Section 242 of the DGCL.

IN WITNESS WHEREOF,ARCABIOPHARMA, INC. has caused this Certificate of Amendment to be signed by its duly authorized officer this ______ day of ________, 2018.

ANNEXA-9

CERTIFICATE OF AMENDMENT

OF

AMENDED AND RESTATED CERTIFICATE OF INCORPORATION

OF

ARCA BIOPHARMA, INC.

ARCABIOPHARMA, INC., a corporation organized and existing under and by virtue of the General Corporation Law of the State of Delaware (the “DGCL”), does hereby certify:

FIRST:               The name of the corporation is ARCA biopharma, Inc. (the “Corporation”).

SECOND:           The date of filing of its original Certificate of Incorporation with the Secretary of State of the State of Delaware was March 16, 2004 under the name “Nuvelo Merger Sub, Inc.”

THIRD:              The Board of Directors (the “Board”) of the Corporation, acting in accordance with the provisions of Sections 141 and 242 of the DGCL, adopted resolutions amending its Amended and Restated Certificate of Incorporation, as amended, as follows:

1.                         Article IV of the Amended and Restated Certificate of Incorporation of the Corporation is hereby amended to add the following provisions in their entirety to the existing provisions of Article IV:

“Effective at 5:01 p.m. Eastern time, on the date of the filing of this Certificate of Amendment to the Amended and Restated Certificate of Incorporation with the Secretary of State of the State of Delaware (the “Effective Time”), the shares of the Corporation’s Common Stock, par value $0.001 per share, issued and outstanding immediately prior to the Effective Time and the shares of Common Stock issued and held in the treasury of the Corporation immediately prior to the Effective Time shall be combined into a smaller number of shares such that each 11 shares of issued and outstanding Common Stock immediately prior to the Effective Time are combined into one validly issued, fully paid and nonassessable share of Common Stock, par value $0.001 per share. Notwithstanding the immediately preceding sentence, no fractional shares shall be issued and, in lieu thereof, upon surrender after the Effective Time of a certificate which formerly represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time, any person who would otherwise be entitled to a fractional share of Common Stock as a result of the combination, following the Effective Time (after taking into account all fractional shares of Common Stock otherwise issuable to such holder), shall be entitled to receive a cash payment equal to the fraction to which such holder would otherwise be entitled multiplied by the fair value of the Common Stock on the date of the Effective Time, as determined by the Board of Directors.

Each stock certificate that, immediately prior to the Effective Time, represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time shall, from and after the Effective Time, automatically and without the necessity of presenting the same for exchange, represent that number of whole shares of Common Stock after the Effective Time into which the shares of Common Stock formerly represented by such certificate shall have been combined (as well as the right to receive cash in lieu of fractional shares of Common Stock after the Effective Time), provided however, that each person of record holding a certificate that represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time shall receive, upon surrender of such certificate, a new certificate evidencing and representing the number of whole shares of Common Stock after the Effective Time into which the shares of Common Stock formerly represented by such certificate shall have been combined.”

FOURTH:           Thereafter, pursuant to a resolution by the Board, this Certificate of Amendment was submitted to the stockholders of the Corporation for their approval in accordance with the provisions of Section 211 and 242 of the DGCL. Accordingly, said proposed amendment has been adopted in accordance with Section 242 of the DGCL.

IN WITNESS WHEREOF,ARCABIOPHARMA, INC. has caused this Certificate of Amendment to be signed by its duly authorized officer this ______ day of ________, 2018.

ANNEXA-10

CERTIFICATE OF AMENDMENT

OF

AMENDED AND RESTATED CERTIFICATE OF INCORPORATION

OF

ARCA BIOPHARMA, INC.

ARCABIOPHARMA, INC., a corporation organized and existing under and by virtue of the General Corporation Law of the State of Delaware (the “DGCL”), does hereby certify:

FIRST:               The name of the corporation is ARCA biopharma, Inc. (the “Corporation”).

SECOND:           The date of filing of its original Certificate of Incorporation with the Secretary of State of the State of Delaware was March 16, 2004 under the name “Nuvelo Merger Sub, Inc.”

THIRD:              The Board of Directors (the “Board”) of the Corporation, acting in accordance with the provisions of Sections 141 and 242 of the DGCL, adopted resolutions amending its Amended and Restated Certificate of Incorporation, as amended, as follows:

1.                         Article IV of the Amended and Restated Certificate of Incorporation of the Corporation is hereby amended to add the following provisions in their entirety to the existing provisions of Article IV:

“Effective at 5:01 p.m. Eastern time, on the date of the filing of this Certificate of Amendment to the Amended and Restated Certificate of Incorporation with the Secretary of State of the State of Delaware (the “Effective Time”), the shares of the Corporation’s Common Stock, par value $0.001 per share, issued and outstanding immediately prior to the Effective Time and the shares of Common Stock issued and held in the treasury of the Corporation immediately prior to the Effective Time shall be combined into a smaller number of shares such that each 12 shares of issued and outstanding Common Stock immediately prior to the Effective Time are combined into one validly issued, fully paid and nonassessable share of Common Stock, par value $0.001 per share. Notwithstanding the immediately preceding sentence, no fractional shares shall be issued and, in lieu thereof, upon surrender after the Effective Time of a certificate which formerly represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time, any person who would otherwise be entitled to a fractional share of Common Stock as a result of the combination, following the Effective Time (after taking into account all fractional shares of Common Stock otherwise issuable to such holder), shall be entitled to receive a cash payment equal to the fraction to which such holder would otherwise be entitled multiplied by the fair value of the Common Stock on the date of the Effective Time, as determined by the Board of Directors.

Each stock certificate that, immediately prior to the Effective Time, represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time shall, from and after the Effective Time, automatically and without the necessity of presenting the same for exchange, represent that number of whole shares of Common Stock after the Effective Time into which the shares of Common Stock formerly represented by such certificate shall have been combined (as well as the right to receive cash in lieu of fractional shares of Common Stock after the Effective Time), provided however, that each person of record holding a certificate that represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time shall receive, upon surrender of such certificate, a new certificate evidencing and representing the number of whole shares of Common Stock after the Effective Time into which the shares of Common Stock formerly represented by such certificate shall have been combined.”

FOURTH:           Thereafter, pursuant to a resolution by the Board, this Certificate of Amendment was submitted to the stockholders of the Corporation for their approval in accordance with the provisions of Section 211 and 242 of the DGCL. Accordingly, said proposed amendment has been adopted in accordance with Section 242 of the DGCL.

IN WITNESS WHEREOF,ARCABIOPHARMA, INC. has caused this Certificate of Amendment to be signed by its duly authorized officer this ______ day of ________, 2018.

ANNEXA-11

CERTIFICATE OF AMENDMENT

OF

AMENDED AND RESTATED CERTIFICATE OF INCORPORATION

OF

ARCA BIOPHARMA, INC.

ARCABIOPHARMA, INC., a corporation organized and existing under and by virtue of the General Corporation Law of the State of Delaware (the “DGCL”), does hereby certify:

FIRST:               The name of the corporation is ARCA biopharma, Inc. (the “Corporation”).

SECOND:           The date of filing of its original Certificate of Incorporation with the Secretary of State of the State of Delaware was March 16, 2004 under the name “Nuvelo Merger Sub, Inc.”

THIRD:               The Board of Directors (the “Board”) of the Corporation, acting in accordance with the provisions of Sections 141 and 242 of the DGCL, adopted resolutions amending its Amended and Restated Certificate of Incorporation, as amended, as follows:

1.                     Article IV of the Amended and Restated Certificate of Incorporation of the Corporation is hereby amended to add the following provisions in their entirety to the existing provisions of Article IV:

“Effective at 5:01 p.m. Eastern time, on the date of the filing of this Certificate of Amendment to the Amended and Restated Certificate of Incorporation with the Secretary of State of the State of Delaware (the “Effective Time”), the shares of the Corporation’s Common Stock, par value $0.001 per share, issued and outstanding immediately prior to the Effective Time and the shares of Common Stock issued and held in the treasury of the Corporation immediately prior to the Effective Time shall be combined into a smaller number of shares such that each 13 shares of issued and outstanding Common Stock immediately prior to the Effective Time are combined into one validly issued, fully paid and nonassessable share of Common Stock, par value $0.001 per share. Notwithstanding the immediately preceding sentence, no fractional shares shall be issued and, in lieu thereof, upon surrender after the Effective Time of a certificate which formerly represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time, any person who would otherwise be entitled to a fractional share of Common Stock as a result of the combination, following the Effective Time (after taking into account all fractional shares of Common Stock otherwise issuable to such holder), shall be entitled to receive a cash payment equal to the fraction to which such holder would otherwise be entitled multiplied by the fair value of the Common Stock on the date of the Effective Time, as determined by the Board of Directors.

Each stock certificate that, immediately prior to the Effective Time, represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time shall, from and after the Effective Time, automatically and without the necessity of presenting the same for exchange, represent that number of whole shares of Common Stock after the Effective Time into which the shares of Common Stock formerly represented by such certificate shall have been combined (as well as the right to receive cash in lieu of fractional shares of Common Stock after the Effective Time), provided however, that each person of record holding a certificate that represented shares of Common Stock that were issued and outstanding immediately prior to the Effective Time shall receive, upon surrender of such certificate, a new certificate evidencing and representing the number of whole shares of Common Stock after the Effective Time into which the shares of Common Stock formerly represented by such certificate shall have been combined.”

FOURTH:           Thereafter, pursuant to a resolution by the Board, this Certificate of Amendment was submitted to the stockholders of the Corporation for their approval in accordance with the provisions of Section 211 and 242 of the DGCL. Accordingly, said proposed amendment has been adopted in accordance with Section 242 of the DGCL.

IN WITNESS WHEREOF,ARCABIOPHARMA, INC. has caused this Certificate of Amendment to be signed by its duly authorized officer this ______ day of ________, 2018.