As filed with the Securities and Exchange Commission on September 4, 2015June 1, 2016

RegistrationNo. 333-             

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORMForm S-3

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

ContraFect Corporation

(Exact name of registrant as specified in its charter)

28 Wells Avenue, Third Floor

Yonkers, New York 10701

(914) 207-2300

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

Julia P. Gregory, Chief Executive Officer

ContraFect CorporationNatalie Bogdanos, General Counsel and Corporate Secretary

28 Wells Avenue, Third Floor

Yonkers New York 10701

(914) 207-2300

(Name, address,Address, including zip code, and telephone number, including area code, of agent for service)

Copies to:

Christopher M. ForresterPeter N. Handrinos, Esq.

ShearmanGregory P. Rodgers, Esq.

Latham & SterlingWatkins LLP

1460 El Camino Real, 2^nd Floor885 Third Avenue

Menlo Park, California 94025New York, New York 10022

+1 (650) 838-3600(212) 906-1200

ApproximateAPPROXIMATE DATE OF COMMENCEMENT OF PROPOSED SALE TO THE PUBLIC:From time to time after the effective date of commencement of proposed sale to the public:

As soon as practicable after this registration statement is declared effective.statement.

If the only securities being registered on this formForm are being offered pursuant to dividend or interest reinvestment plans, please check the following box.  ¨

If any of the securities being registered on this formForm are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box.  x

If this formForm is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ¨

If this formForm is apost-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ¨

If this formForm is a registration statement pursuant to General Instruction I.D. or apost-effective amendment thereto that shall become effective uponon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box.  ¨

If this formForm is apost-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box.  ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, anon-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer,”filer” and “smaller reporting company” inRule 12b-2 of the Exchange Act. (Check one):

Calculation of Registration Fee:CALCULATION OF REGISTRATION FEE

The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 as amended, or until the registration statement shall become effective on such date as the Commission, acting pursuant to said Section 8(a), may determine.

The information in this prospectus is not complete and may be changed. WeThese securities may not sell these securitiesbe sold until the registration statement filed with the Securities and Exchange Commission is effective. This preliminary prospectus is not an offer to sell these securities and we are not soliciting offersnor does it seek an offer to buy these securities in any statejurisdiction where the offer or sale is not permitted.

Subject to completion,Completion, dated September 4, 2015June 1, 2016.

PROSPECTUS

ContraFect Corporation

$100,000,000

Common Stock

Preferred Stock

Debt Securities

Guarantees of Debt Securities

Warrants

Rights

Units

We may offer and sell from time to time common stock, preferred stock, debt securities, warrants, rights and units that include any of these securities. The preferred stock or warrants may be convertible into or exercisable or exchangeable for common or preferred stock or other of our securities. The debt securities may be convertible into, or exercisable or exchangeable for common stock. This prospectus also covers guarantees, if any, of our obligations under any debt securities, which may be given by one or more of our subsidiaries in the future. The shares of our common stock, Class A Warrants and Class B Warrants are listed on the NASDAQ Capital Market under the symbols “CFRX,” “CFRXW” and “CFRXZ,” respectively.

We or any selling stockholders may offer and sell these securities to or through one or more underwriters, dealers and agents, or directly to purchasers, on a continuous or delayed basis.

This prospectus describes some of the general terms that may apply to these securities and the general manner in which they may be offered. The specific terms of any securities to be offered, and the specific manner in which they may be offered, will be described in a supplement to this prospectus. You should read this prospectus and each applicable prospectus supplement carefully before you invest.

See the “Risk Factors” section of this prospectus on page 5, our filings with the SEC and the applicable prospectus supplement for certain risks that you should consider before investing in our securities.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities nor passed upon the accuracy of this prospectus. Any representation to the contrary is a criminal offense.

The date of this prospectus is             , 2015.

TABLE OF CONTENTS

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RISK FACTORS

Investing in our securities involves significant risks. You should review carefully the risks and uncertainties described under the heading “Risk Factors” contained in, or incorporated into, the applicable prospectus supplement and any related free writing prospectus, and under similar headings in the other documents that are incorporated by reference herein or therein. Each of the referenced risks and uncertainties could adversely affect our business, operating results and financial condition, as well as adversely affect the value of an investment in our securities.

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CONTRAFECT CORPORATION

We are a clinical-stage biotechnology company focused on discovering and developing therapeutic protein and antibody products for life-threatening, drug-resistant infectious diseases, particularly those treated in hospital settings. Due to drug-resistant and newly emerging pathogens, hospital acquired infections are currently the fourth leading cause of death in the United States, following heart disease, cancer and stroke. We intend to address drug-resistant infections using our therapeutic product candidates from our lysin and monoclonal antibody platforms to target conserved regions of either bacteria or viruses. Lysins are enzymes that are produced in the life cycle stage of a bacteriophage, a virus that infects and kills bacteria. Lysins digest bacterial cell walls and are fundamentally different than antibiotics because they kill bacteria immediately upon contact. We believe the properties of our lysins make them suitable for the treatment of antibiotic-resistant organisms that can cause serious infections such as Staph aureus bacteremia, pneumonia and osteomyelitis, and the treatment of biofilm-related indications for infected prosthetic joints, indwelling devices and catheters. In addition to our lysins, we are exploring therapies using mAbs that block and disarm virulence factors of bacteria and viruses, rendering them vulnerable to the body’s natural immune response.

We were incorporated under the laws of the State of Delaware in March 2008. Our principal executive offices are located at 28 Wells Avenue, 3^rd Floor, Yonkers, NY 10701, and our telephone number is (914) 207-2340. Our website address is www.contrafect.com. The information contained on our website is not incorporated by reference into this prospectus, and you should not consider any information contained on, or that can be accessed through, our website as part of this prospectus or in deciding whether to purchase our securities. Our securities trade on the NASDAQ Capital Market under the symbols “CFRX,” “CFRXW” and “CFRXZ.”

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DESCRIPTION OF SECURITIES WE MAY OFFER

We may issue from time to time, and we and/or any selling stockholder may offer from time to time, in one or more offerings, the following securities:

This prospectus contains a summary of the material general terms of the various securities that we may offer. The specific terms of the securities will be described in a prospectus supplement, information incorporated by reference or related free writing prospectus, which may be in addition to or different from the general terms summarized in this prospectus. Where applicable, the prospectus supplement, information incorporated by reference or related free writing prospectus will also describe any material United States federal income tax considerations relating to the securities offered and indicate whether the securities offered are or will be listed on any securities exchange. The summaries contained in this prospectus and in any prospectus supplements, information incorporated by reference or related free writing prospectus may not contain all of the information that you would find useful. Accordingly, you should read the actual documents relating to any securities sold pursuant to this prospectus. See “Available Information” and “Incorporation of Certain Information by Reference” for information about how to obtain copies of those documents.

The terms of any particular offering, the initial offering price and the net proceeds to us will be contained in the prospectus supplement, information incorporated by reference or free writing prospectus, relating to such offering.

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DESCRIPTION OF CAPITAL STOCK

The following description of our securities and provisions of our sixth amended and restated certificate of incorporation and second amended and restatedby-laws are summaries and are qualified by reference to such documents. We have filed copies of these documents with the SEC. See “Available Information.”

Common Stock

Preferred Stock

Debt Securities

Warrants

Units

We may offer and sell up to $100,000,000 in the aggregate of the securities identified above from time to time in one or more offerings. This prospectus provides you with a general description of the securities.

Each time we offer and sell securities, we will provide a supplement to this prospectus that contains specific information about the offering and the amounts, prices and terms of the securities. The supplement may also add, update or change information contained in this prospectus with respect to that offering. You should carefully read this prospectus and the applicable prospectus supplement before you invest in any of our securities.

We may offer and sell the securities described in this prospectus and any prospectus supplement to or through one or more underwriters, dealers and agents, or directly to purchasers, or through a combination of these methods. If any underwriters, dealers or agents are involved in the sale of any of the securities, their names and any applicable purchase price, fee, commission or discount arrangement between or among them will be set forth, or will be calculable from the information set forth, in the applicable prospectus supplement. See the sections of this prospectus entitled “About this Prospectus” and “Plan of Distribution” for more information. No securities may be sold without delivery of this prospectus and the applicable prospectus supplement describing the method and terms of the offering of such securities.

INVESTING IN OUR SECURITIES INVOLVES RISKS. SEE THE “RISK FACTORS” ON PAGE 5 OF THIS PROSPECTUS AND ANY SIMILAR SECTION CONTAINED IN THE APPLICABLE PROSPECTUS SUPPLEMENT CONCERNING FACTORS YOU SHOULD CONSIDER BEFORE INVESTING IN OUR SECURITIES.

Our common stock is listed on the Nasdaq Capital Market under the symbol “CFRX.” On May 31, 2016, the last reported sale price of our common stock on the Nasdaq Capital Market was $3.05 per share.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

The date of this prospectus is                      , 2016.

TABLE OF CONTENTS

ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement on Form S-3 that we filed with the U.S. Securities and Exchange Commission, or the SEC, using a “shelf” registration process. By using a shelf registration statement, we may sell securities from time to time and in one or more offerings up to a total dollar amount of $100,000,000 as described in this prospectus. Each time that we offer and sell securities, we will provide a prospectus supplement to this prospectus that contains specific information about the securities being offered and sold and the specific terms of that offering. We may also authorize one or more free writing prospectuses to be provided to you that may contain material information relating to these offerings. The prospectus supplement may also add, update or change information contained in this prospectus with respect to that offering. If there is any inconsistency between the information in this prospectus and the applicable prospectus supplement, you should rely on the prospectus supplement. Before purchasing any securities, you should carefully read both this prospectus and the applicable prospectus supplement, together with the additional information described under the heading “Where You Can Find More Information; Incorporation by Reference.”

We have not, and any underwriter has not, authorized anyone to provide you with any information or to make any representations other than those contained in this prospectus, any applicable prospectus supplement or any free writing prospectuses prepared by or on behalf of us or to which we have referred you. We take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. We will not make an offer to sell these securities in any jurisdiction where the offer or sale is not permitted. You should assume that the information appearing in this prospectus and the applicable prospectus supplement to this prospectus is accurate as of the date on its respective cover, and that any information incorporated by reference is accurate only as of the date of the document incorporated by reference, unless we indicate otherwise. Our business, financial condition, results of operations and prospects may have changed since those dates. This prospectus incorporates by reference, and any prospectus supplement or free writing prospectus may contain and incorporate by reference, market data and industry statistics and forecasts that are based on independent industry publications and other publicly available information. Although we believe these sources are reliable, we do not guarantee the accuracy or completeness of this information and we have not independently verified this information. Although we are not aware of any misstatements regarding the market and industry data presented in this prospectus and the documents incorporated herein by reference, these estimates involve risks and uncertainties and are subject to change based on various factors, including those discussed under the heading “Risk Factors” contained in this prospectus, the applicable prospectus supplement and any related free writing prospectus, and under similar headings in the other documents that are incorporated by reference into this prospectus. Accordingly, investors should not place undue reliance on this information.

When we refer to “ContraFect,” “we,” “our,” “us” and the “Company” in this prospectus, we mean ContraFect Corporation, unless otherwise specified. When we refer to “you,” we mean the holders of the applicable series of securities.

WHERE YOU CAN FIND MORE INFORMATION; INCORPORATION BY REFERENCE

Available Information

We file reports, proxy statements and other information with the SEC. Information filed with the SEC by us can be inspected and copied at the Public Reference Room maintained by the SEC at 100 F Street, N.E., Washington, D.C. 20549. You may also obtain copies of this information by mail from the Public Reference Room of the SEC at prescribed rates. Further information on the operation of the SEC’s Public Reference Room in Washington, D.C. can be obtained by calling the SEC at 1-800-SEC-0330. The SEC also maintains a web site that contains reports, proxy and information statements and other information about issuers, such as us, who file electronically with the SEC. The address of that website ishttp://www.sec.gov.

Our web site address ishttp://www.contrafect.com. The information on our web site, however, is not, and should not be deemed to be, a part of this prospectus.

This prospectus and any prospectus supplement are part of a registration statement that we filed with the SEC and do not contain all of the information in the registration statement. The full registration statement may be obtained from the SEC or us, as provided below. Forms of the indenture and other documents establishing the terms of the offered securities are or may be filed as exhibits to the registration statement. Statements in this prospectus or any prospectus supplement about these documents are summaries and each statement is qualified in all respects by reference to the document to which it refers. You should refer to the actual documents for a more complete description of the relevant matters. You may inspect a copy of the registration statement at the SEC’s Public Reference Room in Washington, D.C. or through the SEC’s website, as provided above.

Incorporation by Reference

The SEC’s rules allow us to “incorporate by reference” information into this prospectus, which means that we can disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is deemed to be part of this prospectus, and subsequent information that we file with the SEC will automatically update and supersede that information. Any statement contained in a previously filed document incorporated by reference will be deemed to be modified or superseded for purposes of this prospectus to the extent that a statement contained in this prospectus modifies or replaces that statement.

We incorporate by reference our documents listed below and any future filings made by us with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended, which we refer to as the “Exchange Act” in this prospectus, between the date of this prospectus and the termination of the offering of the securities described in this prospectus. We are not, however, incorporating by reference any documents or portions thereof, whether specifically listed below or filed in the future, that are not deemed “filed” with the SEC, including our Compensation Committee report and performance graph or any information furnished pursuant to Items 2.02 or 7.01 of Form 8-K or related exhibits furnished pursuant to Item 9.01 of Form 8-K.

This prospectus and any accompanying prospectus supplement incorporate by reference the documents set forth below that have previously been filed with the SEC:

All reports and other documents we subsequently file pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act prior to the termination of this offering, including all such documents we may file with the SEC after the date of the initial registration statement and prior to the effectiveness of the registration statement, but excluding any information furnished to, rather than filed with, the SEC, will also be incorporated by reference into this prospectus and deemed to be part of this prospectus from the date of the filing of such reports and documents.

You may request a free copy of any of the documents incorporated by reference in this prospectus (other than exhibits, unless they are specifically incorporated by reference in the documents) by writing or telephoning us at the following address:

ContraFect Corporation

28 Wells Avenue, Third Floor

Yonkers, New York 10701

(914) 207-2300

Exhibits to the filings will not be sent, however, unless those exhibits have specifically been incorporated by reference in this prospectus and any accompanying prospectus supplement.

THE COMPANY

We are a clinical-stage biotechnology company focused on discovering and developing therapeutic protein and antibody products for the treatment of life-threatening infectious diseases, including those caused by drug-resistant pathogens, particularly those treated in hospital settings. We intend to address drug-resistant infections using product candidates from our lysin and monoclonal antibody platforms that target conserved regions of either bacteria or viruses. Lysins are enzymes derived from naturally occurring bacteriophage which are viruses that infect bacteria. Lysins kill bacteria faster than conventional antibiotics, which typically require bacterial cell division and metabolism in order to kill or stop the growth of bacteria. We believe that the properties of our lysins will make them suitable for targeting antibiotic-resistant organisms, such as Staphylococcus aureus which causes serious infections such as bacteremia, pneumonia and osteomyelitis. In addition, our lysins have demonstrated the ability to clear biofilms in animal models, and we believe they may be useful for the treatment of biofilm-related infections in prosthetic joints, indwelling devices and catheters. Beyond our lysin programs, we are exploring therapies using monoclonal antibodies (“mAbs”) designed to bind to viral targets. Our approach to antibody therapy employs a combination of multiple mAbs to either achieve greater efficacy or provide broader coverage across pathogenic strains.

We were incorporated under the laws of the State of Delaware in March 2008. Our principal executive offices are located at 28 Wells Avenue, 3rd Floor, Yonkers, NY 10701, and our telephone number is (914) 207-2300.

RISK FACTORS

Investment in any securities offered pursuant to this prospectus and the applicable prospectus supplement involves risks. You should carefully consider the risk factors incorporated by reference to our most recent Quarterly Report on Form 10-Q for the period ended March 31, 2016 and any subsequent Annual Report on Form 10-K, Quarterly Reports on Form 10-Q or Current Reports on Form 8-K we file after the date of this prospectus, and all other information contained or incorporated by reference into this prospectus, as updated by our subsequent filings under the Exchange Act, and the risk factors and other information contained in the applicable prospectus supplement before acquiring any of such securities. The occurrence of any of these risks might cause you to lose all or part of your investment in the offered securities.

USE OF PROCEEDS

We intend to use the net proceeds from the sale of the securities as set forth in the applicable prospectus supplement.

RATIO OF EARNINGS TO FIXED CHARGES AND PREFERRED SHARE DIVIDENDS

The following table sets forth the historical ratios of earnings to fixed charges and preferred share dividends for ContraFect for the periods indicated.

For purposes of calculating the ratio above, earnings (loss) consist of income (loss) before income taxes plus fixed charges. Fixed charges include interest expense, non-cash interest expense and other, and an estimate of the interest expense within rental expense.

We did not record earnings for any of the years ended December 31, 2013, 2014 and 2015 and for the three months ended March 31, 2016. Accordingly, our earnings were insufficient to cover fixed charges and preferred stock dividends in such periods and we are unable to disclose a ratio of earnings to fixed charges and preferred stock dividends for such periods. The dollar amount of the deficiency in earnings available for fixed charges and preferred stock dividends for the fiscal years ended December 31, 2012, 2013, 2014 and 2015 and for the three months ended March 31, 2016 was approximately $19,283,000, $23,621,000, $34,618,000, $25,121,000, and $8,923,000, respectively.

DESCRIPTION OF CAPITAL STOCK

The following description of our capital stock is not complete and may not contain all the information you should consider before investing in our capital stock. This description is summarized from, and qualified in its entirety by reference to, our certificate of incorporation, which has been publicly filed with the SEC. See “Where You Can Find More Information; Incorporation by Reference.”

Our authorized capital stock consists of of:

Common Stock

Our common stock is listed on the NASDAQ Capital Market under the symbol “CFRX.” The Transfer Agent and Registrar for our common stock is American Stock Transfer & Trust Company, LLC.

Voting rightsRights.

The holdersHolders of shares ofour common stock are entitled to one vote for each share of common stock held aton all meetingsmatters submitted to a vote of stockholders and written actions in lieu of meetings.do not have cumulative voting rights. An election of directors by our stockholders shall be determined by a plurality of the votes cast by the stockholders entitled to vote on the election. Any matterSubject to the supermajority votes for some matters, other thanmatters shall be decided by the electionaffirmative vote of our stockholders having a majority in voting power of the votes cast by the stockholders present or represented and voting on such matter. Our certificate of incorporation and amended and restated bylaws also provide that our directors may be removed, with or without cause, by the affirmative vote of the holders of at least 75% in voting power of the outstanding shares of capital stock entitled to vote thereon. Subject to the rights of holder of any series of Preferred Stock, any vacancy on our board of directors, and as set forth below shallincluding a vacancy resulting from an enlargement of our board of directors, may be determinedfilled only by vote of a majority of our directors then in office. In addition, the votes cast.affirmative vote of the holders of at least 75% in voting power of the outstanding shares of capital stock entitled to vote thereon is required to amend or repeal, or to adopt any provision inconsistent with, several of the provisions of our certificate of incorporation. See below under “—Anti-Takeover Effects of Delaware Law and Our CharterCertificate of Incorporation and Bylaws—Amendment of Certificate of Incorporation and Bylaws.”

Dividend rights

Holders of common stock are entitled to receive proportionately any dividends as may be declared by our board of directors, subject to any preferential dividend rights of outstanding preferred stock.

Rights upon liquidationUpon Liquidation.

In the event of our liquidation or dissolution, the holders of common stock are entitled to receive proportionately all assets available for distribution to stockholders after the payment of all debts and other liabilities and subject to the prior rights of any outstanding preferred stock.

Other rightsRights.

Holders of common stock have no preemptive, subscription, redemption or conversion rights. The rights, preferences and privileges of holders of common stock are subject to and may be adversely affected by the rights of the holders of shares of any series of preferred stock that we may designate and issue in the future.

Transfer Agent

The transfer agent and registrar for our common stock is American Stock Transfer & Trust Company, LLC.

Dividend

Holders of common stock are entitled to receive proportionately any dividends as may be declared by our board of directors, subject to any preferential dividend rights of outstanding preferred stock. We have never declared or paid any cash dividends on our common stock. We do not intend to pay cash dividends for the foreseeable future. We currently expect to retain all future earnings, if any, for use in the development, operation and expansion of our business. Any determination to pay cash dividends in the future will depend upon, among other things, our results of operations, plans for expansion, tax considerations, available net profits and reserves, limitations under law, financial condition, capital requirements and other factors that our board of directors considers to be relevant.

Preferred Stock

Our authorized capital stock consists of 25,000,000 shares of our preferred stock, par value $0.0001 per share, all of which preferred stock is undesignated. Under the terms of our amended and restated certificate of incorporation, our board of directors is authorized to issue shares of preferred stock in one or more series without stockholder approval. Our board of directors has the discretion to determine the rights, preferences, privileges and restrictions, including voting rights, dividend rights, conversion rights, redemption privileges and liquidation preferences, of each series of preferred stock.

The purpose of authorizing our board of directors to issue preferred stock and determine its rights and preferences is to eliminate delays associated with a stockholder vote on specific issuances. The issuance of preferred stock, while providing flexibility in connection with possible acquisitions, future financings and other corporate purposes, could have the effect of making it more difficult for athird-party third party to acquire, or could discourage a third-partythird party from seeking to acquire, a majority of our outstanding voting stock. There are no

Options

As of May 31, 2016, options to purchase an aggregate of 4,804,227 shares of preferredour common stock were outstanding andunder our 2014 equity compensation plan.

Warrants

PIPE Warrants. In June 2015, in connection with a private placement of securities to institutional investors, we have no present plansissued warrants to issue anypurchase shares of preferred stock.common stock at an exercise price of $8.00 per share, which expire on June 11, 2018. As of May 31, 2016, there were an aggregate of 2,364,066 shares of common stock underlying these warrants. The placement agents in the private placement received warrants to purchase shares of common stock at an exercise price of $4.65 per share, which expire on June 11, 2020. As of May 31, 2016, there were an aggregate of 189,126 shares of common stock underlying these warrants.

IPO Warrants. On August 1, 2014, we closed our initial public offering of units. Each unit consisted of one share of common stock, one Class A Warrant to purchase one share of common stock at an exercise price of $4.80 per share and one Class B Warrant to purchase one-half share of common stock at an exercise price of $4.00 per full share. As of May 31, 2016, there were an aggregate of 6,880,333 shares of common stock underlying these Class A Warrants, which expire on February 1, 2017, and none of the Class B Warrants were outstanding. In connection with the initial public offering, The Maxim Group, LLC received a warrant to purchase 206,410 shares of common stock at an exercise price of $7.50 per share, which expires on July 28, 2019.

Note Warrants. We issued approximately $15.0 million in aggregate principal amount of convertible notes due May 31, 2015 from June 2013 through June 2014. Each purchaser of the convertible notes received a warrant. As of May 31, 2016, there were 3,315,878 shares of common stock underlying these warrants at an exercise price of $3.00 per share, which expire five years from the date of issuance, and none of the convertible notes were outstanding.

Other Warrants. In addition to the foregoing, as of May 31, 2016, we had an aggregate of 547,294 shares of common stock underlying outstanding warrants at a weighted average exercise price of $6.31 per share.

Registration Rights

The shares of common stock underlying the warrants and the shares of common stock issued in connection with our June 2015 private placement are currently registered under a registration statement that has been declared effective by the Securities and Exchange Commission, pursuant to a registration rights agreement entered into between us and the investors of the private placement. The shares of common stock underlying the Class A warrants issued in connection with our IPO are currently registered under a registration statement that has been declared effective by the Securities and Exchange Commission, pursuant to registration rights granted to the holders in accordance with the terms of the warrants.

Anti-Takeover Effects of Delaware Law and Our CharterCertificate of Incorporation and Bylaws

Some provisions of Delaware law, contains, and our certificate of incorporation and our bylaws contain, provisions that could havemake the effect of delaying, deferring or discouraging another party from acquiring control of us. These provisions, which are summarized below, are expected to discourage coercive takeover practices and inadequate takeover bids. These provisions are also designed to encourage persons seeking to acquire controlfollowing transactions more difficult: an acquisition of us to first negotiate with our boardby means of directors.

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Removala tender offer; an acquisition of Directors

A director may be removed only for cause and onlyus by means of a proxy contest or otherwise; or the affirmative vote of the holders of at least 75% of the votes that allremoval of our incumbent officers and directors. It is possible that these provisions could make it more difficult to accomplish or could deter transactions that stockholders wouldmay otherwise consider to be entitled to cast in an annual electiontheir best interest or in our best interests, including transactions which provide for payment of directors. Any vacancy ona premium over the market price for our board of directors, including a vacancy resulting from an enlargementshares.

Undesignated Preferred Stock.The ability of our board of directors, may be filled onlywithout action by votethe stockholders, to issue up to 25,000,000 shares of a majority of our directors then in office.

Stockholder Action by Written Consent; Special Meetings

Our certificate of incorporation provides that any action requiredundesignated preferred stock with voting or permitted to be taken by our stockholders must be effected at a duly called annualother rights or special meeting of such holders and may not be effected by any consent in writing by such holders. Our certificate of incorporation and bylaws also provide that, exceptpreferences as otherwise required by law, special meetings of our stockholders can only be calleddesignated by our board of directors Chairmancould impede the success of any attempt to change control of us. These and other provisions may have the effect of deferring hostile takeovers or delaying changes in control or management of our company.

Stockholder Meetings.Our bylaws provide that a special meeting of stockholders may be called only by our chairman of the board, the chief executive officer or by a resolution adopted by a majority of directors or our Chief Executive Officer.board of directors.

Advance Notice Requirements for Advance Notification of Stockholder ProposalsNominations and Proposals.

Our bylaws establish an advance notice procedure for stockholder proposals to be brought before an annual meeting of stockholders, including proposed nominations of persons for election to our board of directors. Stockholders at an annual meeting will only be able to consider proposals or nominations specified in the notice of meeting or brought before the meeting by or at the direction of our board of directors or by a stockholder of record on the record date for the meeting who is entitled to vote at the meeting and who has delivered timely written notice in proper form to our secretary of the stockholder’s intention to bring such business before the meeting. These provisions could have the effect of delaying until the next stockholder meeting stockholder actions that are favored by the holders of a majority of our outstanding voting securities.

Elimination of Stockholder Action by Written Consent. Our certificate of incorporation eliminates the right of stockholders to act by written consent without a meeting.

Removal of Directors. Our certificate of incorporation and amended and restated bylaws provide that our directors may be removed, with or without cause, by the affirmative vote of the holders of at least 75% in voting power of the outstanding shares of capital stock entitled to vote thereon. Subject to the rights of holder of any series of Preferred Stock, any vacancy on our board of directors, including a vacancy resulting from an enlargement of our board of directors, may be filled only by vote of a majority of our directors then in office.

Stockholders Not Entitled to Cumulative Voting.Our certificate of incorporation does not permit stockholders to cumulate their votes in the election of directors. Accordingly, the holders of a majority of the outstanding shares of our common stock entitled to vote in any election of directors can elect all of the directors standing for election, if they choose, other than any directors that holders of our preferred stock may be entitled to elect.

Delaware Business CombinationAnti-Takeover Statute

. We are subject to the provisions of Section 203 of the Delaware General Corporation Law. Subject to specified exceptions,Under Section 203, prevents apublicly-held Delaware corporationwe would generally be prohibited from engaging in a “business combination”any business combination with any “interested stockholder”interested stockholder for a period of three years following the datetime that the personthis stockholder became an interested stockholder unlessunless:

directors and also officers, and by employee stock plans in which employee participants do not have the right to determine confidentially whether shares held subject to the plan will be tendered in a tender or exchange offer; or

Under Section 203, a prescribed manner. A “business combination” includes, among other things, aincludes:

In general, Section 203 defines an “interested stockholder” is anyinterested stockholder as an entity or person beneficially owning 15% or more of ourthe outstanding voting stock of the corporation and any entity or person affiliated with or controlling or controlled by such entity or person.

Choice of Forum. Our amended and restated bylaws provide that, unless we consent in writing to the selection of an alternative form, the Court of Chancery of the State of Delaware or, if the Court of Chancery does not have jurisdiction, the federal district court for the District of Delaware or other state courts of the State of Delaware) will be the sole and exclusive forum for: (1) any derivative action or proceeding brought on our behalf; (2) any action asserting a claim of breach of a fiduciary duty owed by, or other wrongdoing by, any of our directors, officers, employees or agents to us or our stockholders, creditors or other constituents; (3) any action arising pursuant to any provision of the Delaware General Corporation Law or our certificate of incorporation or bylaws; (4) any action to interpret, apply, enforce or determine the validity of our certificate of incorporation or bylaws; or (5) any action asserting a claim against us governed by the internal affairs doctrine. Our amended and restated bylaws also provide, to the fullest extent permitted by applicable law, that any person or entity purchasing or otherwise acquiring any interest in shares of our capital stock will be deemed to have notice of and to have consented to this choice of forum provision. It is possible that a court of law could rule that the choice of forum provision contained in our amended and restated bylaws is inapplicable or unenforceable if it is challenged in a proceeding or otherwise.

Amendment of Certificate of Incorporation and Bylaws

. The Delaware General Corporation Law provides generally that the affirmative voteamendment of a majorityany of the shares entitled to vote on any matter is required to amend a corporation’s certificate of incorporation or bylaws, unless a corporation’s certificate of incorporation or bylaws, asabove provisions, except for the case may be, requires a greater percentage. Our bylaws may be amended or repealed by a majority vote ofprovision making it possible for our board of directors orto issue preferred stock and the provision prohibiting cumulative voting, would require approval by the affirmative vote of the holders of at least 75% in voting power of the votes that alloutstanding shares of our stockholders would bestock entitled to cast in any annual electionvote thereon.

The provisions of directors. In addition, the affirmative vote of the holders of at least 75% of the votes that all of our stockholders would be entitled to cast in any annual election of directors is required to amend or repeal or to adopt any provisions inconsistent with any of the provisions ofDelaware law, our certificate of incorporation described above under “—Removaland our bylaws could have the effect of Directors”discouraging others from attempting hostile takeovers and, “—Stockholder Action by Written Consent; Special Meetings.”as a consequence, they may also inhibit temporary fluctuations in the market price of our common stock that often result from actual or rumored hostile takeover attempts. These provisions may also have the effect of preventing changes in the composition of our board and management. It is possible that these provisions could make it more difficult to accomplish transactions that stockholders may otherwise deem to be in their best interests.

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DESCRIPTION OF DEBT SECURITIES

The following description, together with the additional information we include in any applicable prospectus supplement, summarizes certain general terms and provisions of the debt securities that we may offer under this prospectus. When we offer to sell a particular series of debt securities, we will describe the specific terms of the series in a supplement to this prospectus. We will also indicate in the supplement to what extent the general terms and provisions described in this prospectus apply to a particular series of debt securities.

We may issue debt securities either separately, or together with, or upon the conversion or exercise of or in exchange for, other securities described in this prospectus. Debt securities may be our senior, senior subordinated or subordinated obligations and, unless otherwise specified in a supplement to this prospectus, the debt securities will be our direct, unsecured obligations and may be issued in one or more distinct series. This

The debt securities will be issued under an indenture between us and a trustee. We have summarized select portions of the indenture below. The summary is not complete. The form of the indenture has been filed as an exhibit to the registration statement and you should read the indenture for provisions that may be important to you. In the summary below, we have included references to the section summarizesnumbers of the materialindenture so that you can easily locate these provisions. Capitalized terms used in the summary and not defined herein have the meanings specified in the indenture.

As used in this section only, “ContraFect,” “we,” “our” or “us” refer to ContraFect Corporation.

General

The terms of the debt securities that are common to all series. Most of the financial terms and other specific material terms of anyeach series of debt securities that we offerwill be established by or pursuant to a resolution of our board of directors and set forth or determined in the manner provided in a resolution of our board of directors, in an officer’s certificate or by a supplemental indenture. (Section 2.2) The particular terms of each series of debt securities will be described in a prospectus supplement or term sheetrelating to be attached to the front of this prospectus. Since the terms of specific debt securities may differ from the general information provided below, you should rely on information in the prospectussuch series (including any pricing supplement or term sheet that contradicts different information below.sheet).

As required by federal law for all bonds and notesWe can issue an unlimited amount of companies that are publicly offered, the debt securities will be governed by a document called an “indenture.” Anunder the indenture is a contract between us and a financial institution acting as trustee on your behalf. The trustee has two main roles. First, the trustee can enforce your rights against us if we default. There are some limitations on the extent to which the trustee acts on your behalf, described in the second paragraph under “Events of Default.” Second, the trustee performs certain administrative duties for us.

Senior and subordinated debt securities will be issued by us under an indenture dated as of             , 20     , as supplemented from time to time (the “indenture”), between us, as issuer, and                     , as trustee (the “trustee”). The debt securitiesthat may be guaranteed byin one or more series with the same or various maturities, at par, at a premium, or at a discount. (Section 2.1) We will set forth in a prospectus supplement (including any pricing supplement or term sheet) relating to any series of our subsidiaries.

The indenture will be subject todebt securities being offered, the aggregate principal amount and governed by the Trust Indenture Act of 1939, as amended (the “TIA”). Thefollowing terms “we,” “our” and “us,” when used to refer to an issuer of securities, means ContraFect Corporation.

Because this section is a summary, it does not describe every aspect of the debt securities, and the indenture. We urge you to read the indenture because it, and not this description, defines your rights as a holder of debt securities. For example, in this section, we use capitalized words to signify terms that are specifically defined in the indenture. Some of the definitions are repeated in this prospectus, but for the rest you will need to read the indenture. See “Where to Find More Information” for information on how to locate the indenture and any supplemental indentures that may be filed.

General Provisions of the Indenture

Each series of debt securities will be obligations of ContraFect Corporation. Any senior securities will rank equally with all other unsecured and unsubordinated indebtedness of ContraFect Corporation. Any subordinated securities will be subordinated in right of payment to the prior payment in full of the senior indebtedness of ContraFect Corporation as more fully described in a prospectus supplement or term sheet.

The indenture provides that any debt securities proposed to be sold under this prospectus and the attached prospectus supplement or term sheet (“offered debt securities”) and any debt securities issuable upon the exercise of debt warrants or upon conversion or exchange of other offered securities (“underlying debt securities”), as well as other unsecured debt securities, may be issued under the indenture in one or more series.

You should read the prospectus supplement or term sheet for the material terms of the offered debt securities and any underlying debt securities, including the following:if applicable:

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For purposes

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The indenture does not contain any provisions that give you protection in the event we issue a large amount

Payment

We may issue debt securities that provide for an amount less than their stated principal amount to be due and payable upon declaration of acceleration of their maturity pursuant to the terms of the indenture. We will provide you with information on the federal income tax considerations and other special considerations applicable to any of these debt securities in the applicable prospectus supplement.

If we denominate the purchase price of any of the debt securities must be made in immediately available funds.

The authorized denominationsa foreign currency or currencies or a foreign currency unit or units, or if the principal of and any premium and interest on any series of debt securities denominatedis payable in U.S. dollarsa foreign currency or currencies or a foreign currency unit or units, we will provide you with information on the restrictions, elections, general tax considerations, specific terms and other information with respect to that issue of debt securities and such foreign currency or currencies or foreign currency unit or units in the applicable prospectus supplement.

Transfer and Exchange

Each debt security will be represented by either one or more global securities registered in the name of The Depository Trust Company, or the Depositary, or a minimum denominationnominee of $2,000the Depositary (we will refer to any debt security represented by a global debt security as a “book-entry debt security”), or a certificate issued in definitive registered form (we will refer to any debt security represented by a certificated security as a “certificated debt security”) as set forth in the applicable prospectus supplement. Except as set forth under the heading “Global Debt Securities and integral multiplesBook-Entry System” below, book-entry debt securities will not be issuable in certificated form.

Certificated Debt Securities. You may transfer or exchange certificated debt securities at any office we maintain for this purpose in accordance with the terms of $1,000 above the minimum denomination. The authorized denominations of foreign currency notesindenture. (Section 2.4) No service charge will be made for any transfer or exchange of certificated debt securities, but we may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection with a transfer or exchange. (Section 2.7)

You may effect the transfer of certificated debt securities and the right to receive the principal of, premium and interest on certificated debt securities only by surrendering the certificate representing those certificated debt securities and either reissuance by us or the trustee of the certificate to the new holder or the issuance by us or the trustee of a new certificate to the new holder.

Global Debt Securities and Book-Entry System. Each global debt security representing book-entry debt securities will be deposited with, or on behalf of, the Depositary, and registered in the name of the Depositary or a nominee of the Depositary. Please see “Global Securities.”

Covenants

We will set forth in the applicable prospectus supplement or term sheet.any restrictive covenants applicable to any issue of debt securities. (Article IV)

Interest and Interest RatesNo Protection in the Event of a Change of Control

Each debt security will begin to accrue interest fromUnless we state otherwise in the date it is originally issued. The relatedapplicable prospectus supplement, or term sheet will describe the method of determining the interest rate.

Interest on the debt securities other than in global form denominated in U.S. dollars will be paid by check mailed on an Interest Payment Date to the persons entitled thereto to the addresses of suchnot contain any provisions which may afford holders as they appear in the security register or, at our option, by wire transfer to a bank account maintained by the holder. The principal of, and premium, if any, and, if other than an Interest Payment Date, interest on debt securities denominated in U.S. dollars, together with interest accrued and unpaid thereon, due on the Maturity Date will be paid in immediately available funds upon surrender of such debt securities at the corporate trust office of the trustee in The City of New York, or, at our option, by wire transfer of immediately available funds to an account with a bank designated at least 15 calendar days prior to the Maturity Date by the applicable registered holder, provided the particular bank has appropriate facilities to receive these payments and the particular note is presented and surrendered at the office or agency maintained by us for this purpose in the Borough of Manhattan, The City of New York, in time for the trustee to make these payments in accordance with its normal procedures.

Payment and Paying Agents

We will pay interest to the person listed in the trustee’s records as the owner of the debt security at the close of business on a particular day in advance of each regularly scheduled date for interest, even if that person no longer owns the debt security on the interest due date. That day, typically set at a date approximately two weeks prior to the interest due date, is called the “record date.” Because we will pay all the interest for an interest period to the holders on the record date, holders buying and selling debt securities must work out between themselves the appropriate purchase price. The most common manner is to adjust the sales price of the debt securities to prorate interest fairly between buyer and seller based on their respective ownership periods within the particular interest period. This prorated interest amount is called “accrued interest.”

Payments on Global Securities

We will make payments on a global security in accordance with the applicable policies of the depositary as in effect from time to time. Under those policies, we will make payments directly to the depositary, or its nominee, and not to any indirect holders who own beneficial interestsprotection in the global security. An indirect holder’s right to those payments will be governed by the rules and practices of the depositary and its participants.

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Payments on Certificated Debt Securities

We will make payments onevent we have a certificated debt security as follows. We will pay interest that is due on an interest payment date by check mailed on the interest payment date to the holder at hischange in control or her address shown on the trustee’s records as of the close of business on the regular record date. We will make payments of principal and premium, if any, duly and punctually to the office of the trustee.

Alternatively, if the holder asks us to do so, we may pay any amount that becomes due on the debt security by wire transfer of immediately available funds to an account at a bank in New York City, on the due date. To request payment by wire, the holder must give the trustee or other paying agent appropriate transfer instructions at least 15 calendar days before the requested wire payment is due. In the case of any interest payment due on an interest payment date, the instructions must be given by the person who is the holder on the relevant regular record date. Any wire instructions, once properly given, will remain in effect unless and until new instructions are given in the manner described above. In addition, see the description under “Interest and Interest Rates.”event of a highly leveraged transaction (whether or not such transaction results in a change in control) which could adversely affect holders of debt securities.

Material Covenants

Consolidation, Merger and Sale or Conveyance. The indenture provides that weof Assets

We may not consolidate with or merge with or into, any other entity or convey, transfer or lease itsall or substantially all of our properties and assets as an entirety or substantially as an entirety to any entity,person (a “successor person”) unless:

Notwithstanding the indenture, and no event which, after notice or lapseabove, any of time or both, would become an Event of Default, has happened and is continuing; and

In case of any such consolidation, merger, conveyancemerge into or transfer the successor entity will succeed to and be substituted for us as obligor on the debt securities with the same effect as if it had been named in the indenture as issuer.

Restrictions on Liens

We will not, and will not permit any Restricted Subsidiary to, create, incur, issue, assume or guarantee any indebtedness for money borrowed secured by a Mortgage (“Secured Debt”) upon any Operating Property or any shares of stock or indebtedness for borrowed money of any Restricted Subsidiary, whether owned at the date of the indenture or thereafter acquired, without effectively providing concurrently that the debt securities of each series then outstanding under the indenture are secured equally and ratably with or, at our option, prior to such Secured Debt so long as such Secured Debt shall be so secured.

The foregoing restriction shall not apply to, and there shall be excluded from Secured Debt in any computation under such restriction, Secured Debt secured by:

(1) mortgages on any property, shares of stock or indebtedness for borrowed money of any corporation existing at the time such corporation becomes a Restricted Subsidiary;

(2) mortgages on property or shares of stock existing at the time of acquisition of such property or stock by us or a Restricted Subsidiary or existing as of the original date of the applicable indenture;

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(3) mortgages to secure the payment of all or any part of the price of acquisition, construction or improvement of such property or stock by us or a Restricted Subsidiary, orits properties to secure any Secured Debt incurred by us or a Restricted Subsidiary, prior to, at the time of, or within 360 days after, the later of the acquisition or completion of construction (including any improvements on an existing property), which Secured Debt is incurred for the purpose of financing all or any part of the purchase price thereof or construction of improvements thereon;provided,however, that, in the case of any such acquisition, construction or improvement, the Mortgage shall not apply to any property theretofore owned by us or a Restricted Subsidiary, other than, in the case of any such construction or improvement, any theretofore substantially unimproved real property on which the property or improvement so constructed is located;us. (Section 5.1)

(4) mortgages securing Secured Debt of a Restricted Subsidiary owing to us or to another Restricted Subsidiary;

(5) mortgages on property of a corporation existing at the time such corporation is merged into or consolidated with us or a Restricted Subsidiary or at the time of a sale, lease or other disposition of the properties of a corporation or firm as an entirety or substantially as an entirety to us or a Restricted Subsidiary;

(6) mortgages on property of us or a Restricted Subsidiary in favor of the United States or any state thereof, or any department, agency or instrumentality or political subdivision of the United States or any state thereof, or in favor of any other country or any political subdivision thereof, or any department, agency or instrumentality of such country or political subdivision, to secure partial progress, advance or other payments pursuant to any contract or statute or to secure any indebtedness incurred for the purpose of financing all or any part of the purchase price or the cost of construction of the property subject to such Mortgages;

(7) any extension, renewal or replacement (or successive extensions, renewals or replacements) in whole or in part of any Mortgage referred to in clauses (1) through (6) above and (9) below; provided, however, that the principal amount of Secured Debt so secured shall not exceed the principal amount of Secured Debt so secured at the time of such extension, renewal or replacement, and that such extension, renewal or replacement shall be limited to all or a part of the property which secured the Mortgage so extended, renewed or replaced (plus improvements and construction on such property);

(8) mortgages upon any Operating Property, or any transfer or disposition of any Operating Property, that is created or implemented as a necessary component of a bond for title transaction, payment in lieu of tax agreement or other tax incentive vehicle designed to provide us or any Subsidiary with certain ad valorem property tax savings or other incentive savings; or

(9) mortgages to secure Hedging Obligations entered into the ordinary course of business to purchase any raw material or other commodity or to hedge risks or reduce costs with respect to the interest rate, currency or commodity exposure of us or any Restricted Subsidiary of ours and not for speculative purposes.

Notwithstanding the foregoing, we and any one or more our Restricted Subsidiaries may, however, without securing any debt securities, create, incur, issue, assume or guarantee Secured Debt secured by a Mortgage if, after giving effect to the transaction, the aggregate of the Secured Debt then outstanding (not including Secured Debt permitted under the above exceptions) does not exceed 15% of our Consolidated Net Tangible Assets as shown on our financial statements as of the end of the fiscal year preceding the date of determination.

“Commodity Agreement” means any forward contract, commodity swap, commodity option or other financial agreement or arrangement relating to, or the value of which is dependent upon. fluctuations in commodity prices.

“Consolidated Net Tangible Assets” means the total assets of ContraFect Corporation and its Restricted Subsidiaries (including, without limitation, any net investment in Subsidiaries that are not Restricted Subsidiaries) after deducting therefrom (a) all current liabilities (excluding any thereof constituting indebtedness for borrowed money) and (b) all goodwill, trade names, trademarks, franchises, patents, unamortized debt discount and expense, organization and developmental expenses and other like segregated intangibles, all as computed by us and our Restricted Subsidiaries in accordance with generally accepted accounting principles as of the end of the fiscal year preceding the date of determination;provided, that any items constituting deferred income taxes, deferred investment tax credit or other similar items shall not be taken into account as a liability or as a deduction from or adjustment to total assets.

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“Currency Agreement” means any foreign exchange contract, currency swap agreement or other similar agreement with respect to currency values.

“GAAP” means U.S. generally accepted accounting principles set forth in the opinions and pronouncements of the Accounting Principles Board of the American Institute of Certified Public Accountants and statements and pronouncements of the Financial Accounting Standards Board or in such other statements by such other entity as have been approved by a significant segment of the accounting profession that are applicable at the date of any relevant calculation or determination.

“Hedging Obligations” of any Person means the obligations of such Person pursuant to any Interest Rate Agreement, Currency Agreement, Commodity Agreement or derivative contract entered into to hedge interest rate risk, currency exchange risk and commodity price risk.

“Interest Rate Agreement” means any interest rate swap agreement, interest rate cap agreement or other financial agreement or arrangement with respect to exposure to interest rates.

“Mortgage” or “Mortgages” means any mortgage, pledge, lien, security interest or other encumbrances upon any Operating Property or any shares of stock or on indebtedness for borrowed money of any Restricted Subsidiary (whether such Operating Property, shares of stock or indebtedness for borrowed money are now owned or hereafter acquired).

“Operating Property” means each plant or facility of ContraFect Corporation or a Restricted Subsidiary located within the United States except any such plant or facility which the board of directors of ContraFect Corporation by resolution reasonably determines not to be of material importance to the total business conducted by us and our Restricted Subsidiaries.

“Person” means any individual, corporation, partnership, joint venture, trust, unincorporated organization or government or any agency or political subdivision thereof.

“Restricted Subsidiary” means any Subsidiary of us (i) substantially all of the property of which is located, or substantially all of the business of which is carried on, within the United States, and (ii) which owns or is the lessee of any Operating Property.

“Subsidiary” means (1) any corporation of which at least a majority of the outstanding stock having by the terms thereof ordinary voting power for the election of directors of such corporation (irrespective of whether or not at the time stock of any other class or classes of such corporation shall have or might have voting power by reason of the happening of any contingency) is at the time directly or indirectly owned by the us or by one or more other Subsidiaries and (2) any other Person in which we or one or more other Subsidiaries, directly or indirectly, at the date of determination, (x) own at least a majority of the outstanding ownership interests or (y) have the power to elect or direct the election of, or to appoint or approve the appointment of, at least the majority of the directors, trustees or managing members of, or other persons holding similar positions with, such Person.

Restrictions on Sale and Leaseback Transactions

We will not, and will not permit any Restricted Subsidiary to, enter into any Sale and Leaseback Transaction unless:

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“Attributable Debt” under the indenture means the present value (discounted at the interest rate inherent in the lease, compounded annually) of the obligation of a lessee for net rental payments during the remaining term of any lease (including any period for which such lease has been extended).

“Sale and Leaseback Transaction” means any arrangement with any person providing for the leasing by us or any Restricted Subsidiary of any Operating Property, whether such Operating Property is now owned or hereafter acquired (except for temporary leases for a term, including renewals at the option of the lessee, of not more than three years and except for leases between us and a Restricted Subsidiary or between Restricted Subsidiaries), which property has been or is to be sold or transferred by us or such Restricted Subsidiary to such person with the intention of taking back a lease of such property.

Events of Default

An“Event of Default” means with respect to any series of debt securities, any of the following:

No Event of Default with respect to a particular series of debt securities (except as to certain events of bankruptcy, insolvency or reorganization) necessarily constitutes an Event of Default with respect to any other series of debt securities. (Section 6.1) The occurrence of certain Events of Default or an acceleration under the indenture may constitute an event of default under certain indebtedness of ours or our subsidiaries outstanding from time to time.

We will provide the trustee written notice of any Default or Event of Default within 30 days of becoming aware of the occurrence of such Default or Event of Default, which notice will describe in reasonable detail the status of such Default or Event of Default and what action we are taking or propose to take in respect thereof. (Section 6.1)

If an Event of Default with respect to the debt securities of any series is defined inat the indenture as:

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The indenture provides that:

Under the indenture,expense which might be incurred by it in performing such duty or exercising such right or power. (Section 7.1(e)) Subject to certain rights of the trustee, must give to the holders of debt securities of any series notice of all uncured defaults known to it with respect to the debt securities of such series within 90 days after such a default occurs (the term default to include the events specified above without notice or grace periods); provided that, except in the case of default in the payments of principal of or any premium or interest on any of the debt securities of such series, the trustee will be protected in withholding such notice if it in good faith determines that the withholding of such notice is in the best interest of the holders of such debt securities.

No holder of any debt securities may institute any action under the indenture unless:

The holders of a majority in aggregate principal amount of the outstanding debt securities of any series will have the right subject to certain limitations, to direct the time, method and place of conducting any proceeding for any remedy available to the trustee or exercising any trust or power conferred on the trustee with respect to the debt securities of suchthat series. The(Section 6.12)

No holder of any debt security of any series will have any right to institute any proceeding, judicial or otherwise, with respect to the indenture provides that, if an eventor for the appointment of default occurs and is continuing, thea receiver or trustee, in exercising its rights and powersor for any remedy under the indenture, will be requiredunless:

Notwithstanding any other provision in the conductindenture, the holder of his own affairs. any debt security will have an absolute and unconditional right to receive payment of the principal of, premium and any interest on that debt security on or after the due dates expressed in that debt security and to institute suit for the enforcement of payment. (Section 6.8)

The indenture further provides that the trustee shall not be required to expend or risk its own funds or otherwise incur any financial liability in the performance of any of its duties under the indenture unless it has reasonable grounds for believing that repayment of such funds or adequate indemnity against such risk or liability is reasonably assured to it.

We must furnish to the trusteerequires us, within 120 days after the end of eachour fiscal year, to furnish to the trustee a statement signed by an officer thereofas to compliance with the indenture. (Section 4.3) If a Default or Event of Default occurs and is continuing with respect to the effect thatsecurities of any series and if it is known to a review of our activities during such year and our performance under the indenture and the termsresponsible officer of the trustee, the trustee shall mail to each Securityholder of the securities of that series notice of a Default or Event of Default within 90 days after it occurs or, if later, after a responsible officer of the trustee has knowledge of such Default or Event of Default. The indenture provides that the trustee may withhold notice to the holders of debt securities has been made, and,of any series of any Default or Event of Default (except in payment on any debt securities of that series) with respect to debt securities of that series if the knowledgetrustee determines in good faith that withholding notice is in the interest of the signatories based on such review, we have complied with all conditions and covenantsholders of the indenture or, if we are in default, specifying such default.those debt securities. (Section 7.5)

Modification of the Indentureand Waiver

We and the trustee may modify, amend or supplement the indenture or the debt securities of any series without the consent of the holdersany holder of theany debt securities issued under such indenture, enter into supplemental indentures for, among others, one or more of the following purposes:security:

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With certain exceptions,the SEC in order to effect or maintain the qualification of the indenture orunder the rights ofTrust Indenture Act. (Section 9.1)

We may also modify and amend the holders of the debt securities may be modified by us and the trusteeindenture with the consent of the holders of at least a majority in principal amount of the outstanding debt securities of each series affected by the modifications or amendments. We may not make any modification or amendment without the consent of the holders of each affected debt security then outstanding if that amendment will:

Except for certain specified provisions, the percentageholders of at least a majority in principal amount of the outstanding debt securities of any series may on behalf of the consent whose holders is required for any such modification, or the consent of whose holders is required for any waiverall debt securities of that series waive our compliance with certain provisions of the indenture or certain defaults thereunder and their consequences provided forindenture. (Section 9.2) The holders of a majority in the indenture; or

Defeasance

The following provisions will be applicable to eachof any series of debt securities unless we state in the applicable prospectus supplement or term sheet that the provisions of covenant defeasance and full defeasance will not be applicable to that series.

Covenant Defeasance

Under current United States federal tax law, we can make the deposit described below and be released from somemay on behalf of the restrictive covenants in the indenture under which the particular series was issued. This is called “covenant defeasance.” In that event, you would lose the protection of those restrictive covenants but would gain the protection of having money and government securities set aside in trust to repay your debt securities. In order to achieve covenant defeasance, we must do the following:

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If we accomplish covenant defeasance, you can still look to us for repayment of the debt securities if there were a shortfall in the trust deposit or the trustee is prevented from making payment. In fact, if one of the remaining Events of Default occurred (such as our bankruptcy) and the debt securities became immediately due and payable, there might be a shortfall. Depending on the event causing the default, you may not be able to obtain payment of the shortfall.

Full Defeasance

If there is a change in United States federal tax law, as described below, we can legally release ourselves from all payment and other obligations on the debt securities of a particular series (called “full defeasance”) if we put in place the following other arrangements for you to be repaid:

No Personal Liability of Directors, Officers, Employees or exchangeStockholders

None of thoseour past, present or future directors, officers, employees or stockholders, as such, will have any liability for any of our obligations under the debt securities duringor the period beginning 15 days before the day we mail the noticeindenture or for any claim based on, or in respect or by reason of, redemptionsuch obligations or their creation. By accepting a debt security, each holder waives and ending on the day of that mailing, in order to freeze the list of holders to prepare the mailing. We may also refuse to register transfers or exchanges of any certificated debt securities selected for redemption, except that we will continue to permit transfers

releases all such liability. This waiver and exchangesrelease is part of the unredeemed portion of any debt security that will be partially redeemed.

If a registered debt security is issued in book–entry form, onlyconsideration for the depositary will be entitled to transfer and exchange the debt security as described in this subsection, since it will be the sole holderissue of the debt security.securities. However, this waiver and release may not be effective to waive liabilities under U.S. federal securities laws, and it is the view of the SEC that such a waiver is against public policy.

Resignation of TrusteeGoverning Law

The trustee may resignindenture and the debt securities, including any claim or be removed at any time with respectcontroversy arising out of or relating to one or more series of indenture securities provided that a successor trustee is appointed to act with respect to these series. In the event that two or more persons are acting as trustee with respect to different series of indenture securities under the indenture eachor the securities, will be governed by the laws of the trustees will be a trusteeState of a trust separate and apart from the trust administered by any other trustee.

The Trustee Under the Indenture

The trustee may be one of a number of banks with which we maintain ordinary banking relationships and from which we may obtain credit facilities and lines of credit in the future. The trustee may also serve as trustee under other indentures under which we are the obligor in the future.New York. (Section 10.10)

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DESCRIPTION OF WARRANTS

General

We may issue warrants tofor the purchase of shares of our common stock or preferred stock or of debt securities, or any combination thereof.securities. We may issue the warrants independently or together with any underlyingother securities, and the warrants may be attached to or separate from the underlyingany offered securities. We may also issue aEach series of warrants will be issued under a separate warrant agreement to be entered into between us and the investors or a warrant agent. The warrant agent will act solely as our agent in connection with the warrants of such series and will not assume any obligation or relationship of agency for or with holders or beneficial owners of warrants.

The following description is a summary of selectedmaterial provisions relating to the warrants that we may issue. The summary is not complete. When warrants are offered in the future, a prospectus supplement, information incorporated by reference or related free writing prospectus, as applicable, will explain the particular terms of those securities and the extent to which these general provisions may apply. The specific terms of the warrants as described in a prospectus supplement information, incorporated by reference or related free writing prospectus will supplement and if applicable, may modify or replace the general terms described in this section.

This summary and any description of warrants in the applicable prospectus supplement, information incorporated by reference or related free writing prospectus iswarrant agreements are subject to, and is qualified in itstheir entirety by reference to, all the provisions of any specificthe warrant document or agreement which we will file with the SEC for incorporation by reference into this prospectus. See “Available Information” and “Incorporation of Certain Information by Reference” for information on how to obtain a copy of a warrant document when it is filed.

When we refercertificate applicable to a particular series of warrants. The terms of any warrants we mean all warrants issued as part ofoffered under a prospectus supplement may differ from the same series underterms described below. We urge you to read the applicable warrant agreement.

Terms

The applicable prospectus supplement information incorporated by reference orand any related free writing prospectus, as well as the complete warrant agreements and warrant certificates that contain the terms of the warrants.

The particular terms of any issue of warrants will be described in the prospectus supplement relating to the issue. Those terms may describe include:

We have obtained the information in this section and elsewhere in this prospectus concerning DTC and DTC’s book-entry system from sources that are believed to be reliable, but we take no responsibility for the accuracy of this information.

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PLAN OF DISTRIBUTION

We may distributesell the securities from time to time pursuant to underwritten public offerings, negotiated transactions, block trades or a combination of these methods or through underwriters or dealers, through agents and/or directly to one or more purchasers. The securities may be distributed from time to time in one or more transactions transactions:

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We may also make direct sales through subscription rights distributed to our existing stockholders on a pro rata basis, which may or may not be transferable. In any distribution of subscription rights to our stockholders, if all of the underlying securities are not subscribed for, we may then sell the unsubscribed securities directly to third parties or may engage the services of one or more underwriters, dealers or agents, including standby underwriters, to sell the unsubscribed securities to third parties.

Some or all of the securitiesEach time that we offer though this prospectus may be new issues of securities with no established trading market. Any underwriters to whom we sell our securities for public offering and sale may make a market in those securities, but they will not be obligated to do so and they may discontinue any market making at any time without notice. Accordingly, we cannot assure you of the liquidity of, or continued trading markets for, any securities that we offer.

We will indicate the extent to which we anticipate that a secondary market for the securities will be available in the prospectus supplement. Our common stock and warrants are listed on the NASDAQ Capital Market. Except as indicated in the applicable prospectus supplement, securities other than those are not expected to be listed on any securities exchange.

Agents may, from time to time, solicit offers to purchase the securities. If required, we will name in the applicable prospectus supplement, document incorporated by reference or related free writing prospectus, as applicable, any agent involved in the offer or sale of the securities and set forth any compensation payable to the agent. Unless otherwise indicated, any agent will be acting on a best efforts basis for the period of its appointment. Any agent selling the securities covered by this prospectus, may be deemed to be an underwriter, as that term is defined in the Securities Act, of the securities.

If underwriters are used in an offering, securitieswe will be acquired by the underwriters for their own account and may be resold, from time to time, in one or more transactions, including negotiated transactions, atprovide a fixed public offering price or at varying prices determined at the time of sale, or under delayed delivery contracts or other contractual commitments. Securities may be offered to the public either through underwriting syndicates represented by one or more managing underwriters or directly by one or more firms acting as underwriters. If an underwriter or underwriters are used in the sale of securities, an underwriting agreement will be executed with the underwriter or underwriters at the time an agreement for the sale is reached.

The accompanying prospectus supplement or supplements that will set forth the terms of the offering anddescribe the method of distribution and will identify any firms acting as underwriters, dealers or agents in connection withset forth the terms and conditions of the offering including:

If a dealer is usedutilized in the sale of the securities we or an underwriterbeing offered by this prospectus, the securities will sell the securitiesbe sold to the dealer, as principal. The dealer may then resell the securities to the public at varying prices to be determined by the dealer at the time of resale. To

If an underwriter is utilized in the extent required, wesale of the securities being offered by this prospectus, an underwriting agreement will set forthbe executed with the underwriter at the time of sale and the name of any underwriter will be provided in the prospectus supplement document incorporated by reference or related free writing prospectus, as applicable,that the nameunderwriter will use to make resales of the dealer andsecurities to the termspublic. In connection with the sale of the transactions.securities, we or the purchasers of securities for whom the underwriter may act as agent, may compensate the underwriter in the form of underwriting discounts or commissions. The underwriter may sell the securities to or through dealers, and those dealers may receive compensation in the form of discounts, concessions or commissions from the underwriters and/or commissions from the purchasers for which they may act as agent. Unless otherwise indicated in a prospectus supplement, an agent will be acting on a best efforts basis and a dealer will purchase securities as a principal, and may then resell the securities at varying prices to be determined by the dealer.

We may directly solicit offersAny compensation paid to purchaseunderwriters, dealers or agents in connection with the offering of the securities, and may make salesany discounts, concessions or commissions allowed by underwriters to participating dealers will be provided in the applicable prospectus supplement. Underwriters, dealers and agents participating in the distribution of the securities directly to institutional investors or others. These persons may be deemed to be underwriters within the meaning of the Securities Act with respect toof 1933, as amended, and any discounts and commissions received by them and any profit realized by them on resale of the securities. To the extent required, the prospectus supplement, document incorporated by reference or related free writing prospectus, as applicable, will describe the terms of any such sales, including the terms of any bidding or auction process, if used.

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Agents, underwriters and dealerssecurities may be entitled underdeemed to be underwriting discounts and commissions. We may enter into agreements which may be entered into with us to indemnificationindemnify underwriters, dealers and agents against specifiedcivil liabilities, including liabilities incurred under the Securities Act, or to contributioncontribute to payments they may be required to make in respect of such liabilities. If required, the prospectus supplement, documents incorporated by reference or related free writing prospectus, as applicable, will describe the termsthereof and conditions of such indemnification or contribution. Some of the agents, underwriters or dealers, or their affiliates may be customers of, engage in transactions with or perform servicesto reimburse those persons for us, our subsidiaries or affiliates in the ordinary course of business.

Under the securities laws of some states, the securities offered by this prospectus may be sold in those states only through registered or licensed brokers or dealers.certain expenses.

Any personcommon stock will be listed on the Nasdaq Capital Market, but any other securities may or may not be listed on a national securities exchange. To facilitate the offering of securities, certain persons participating in the distribution of common stock registered under the registration statement that includes this prospectus will be subject to applicable provisions of the Exchange Act, and the applicable SEC rules and regulations, including, among others, Regulation M, which may limit the timing of purchases and sales of any of our common stock by any such person. Furthermore, Regulation M may restrict the ability of any person engaged in the distribution of our common stock to engage in market-making activities with respect to our common stock. These restrictions may affect the marketability of our common stock and the ability of any person or entity to engage in market-making activities with respect to our common stock.

Certain persons participating in an offering may engage in over-allotment, stabilizing transactions short-covering transactions and penalty bids in accordance with Regulation M under the Exchange Act that stabilize, maintain or otherwise affect the price of the offered securities. This may include over-allotments or short sales of the securities, which involve the sale by persons participating in the offering of more securities than were sold to them. In these circumstances, these persons would cover suchover-allotments or short positions by making purchases in the open market or by exercising their over-allotment

option, if any. In addition, these persons may stabilize or maintain the price of the securities by bidding for or purchasing securities in the open market or by imposing penalty bids, whereby selling concessions allowed to dealers participating in the offering may be reclaimed if securities sold by them are repurchased in connection with stabilization transactions. The effect of these transactions may be to stabilize or maintain the market price of the securities at a level above that which might otherwise prevail in the open market. These transactions may be discontinued at any time.

We may engage in at the market offerings into an existing trading market in accordance with Rule 415(a)(4) under the Securities Act. In addition, we may enter into derivative transactions with third parties, or sell securities not covered by this prospectus to third parties in privately negotiated transactions. If the applicable prospectus supplement so indicates, in connection with those derivatives, the third parties may sell securities covered by this prospectus and the applicable prospectus supplement, including in short sale transactions. If so, the third party may use securities pledged by us or borrowed from us or others to settle those sales or to close out any related open borrowings of stock, and may use securities received from us in settlement of those derivatives to close out any related open borrowings of stock. The third party in such activitiessale transactions will occur, theybe an underwriter and, if not identified in this prospectus, will be named in the applicable prospectus supplement (or a post-effective amendment). In addition, we may otherwise loan or pledge securities to a financial institution or other third party that in turn may sell the securities short using this prospectus and an applicable prospectus supplement. Such financial institution or other third party may transfer its economic short position to investors in our securities or in connection with a concurrent offering of other securities.

The specific terms of any lock-up provisions in respect of any given offering will be described in the applicable prospectus supplement.

This prospectusIn compliance with the guidelines of the Financial Industry Regulatory Authority, Inc., or FINRA, the maximum consideration or discount to be received by any FINRA member or independent broker dealer may be amended or supplemented from time to time, if required, to describe a specific plannot exceed 8% of distribution.

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SELLING STOCKHOLDERS

Selling stockholders are persons or entities that, directly or indirectly, have acquired or will from time to time acquire from us, our securities. Such selling stockholdersThe underwriters, dealers and agents may be parties to registration rights agreementsengage in transactions with us, or we otherwise may have agreed or will agree to register their securitiesperform services for resale. The initial purchasersus, in the ordinary course of our securities, as well as their transferees, pledges, donees or successors, all of whom we refer to as “selling stockholders,” may from time to time offer and sell our securities pursuant to this prospectus and any applicable prospectus supplement.

The applicable prospectus supplement will set forth the name of each of the selling stockholders and the number of securities beneficially owned by such selling stockholder that are covered by such prospectus supplement. The applicable prospectus supplement will also disclose whether any of the selling stockholders has held any position or office with, has been employed by or otherwise has had a material relationship with us during the three years prior to the date of the applicable prospectus supplement.business for which they receive compensation.

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LEGAL MATTERS

ShearmanLatham & SterlingWatkins LLP will pass upon certain legal matters relating to the validityissuance and sale of the securities offered pursuant to thishereby on behalf of ContraFect Corporation. Additional legal matters may be passed upon for us or any underwriters, dealers or agents, by counsel that we will name in the applicable prospectus for us.supplement.

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EXPERTS

Ernst & Young LLP, an independent registered public accounting firm, has audited our financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2014,2015, as set forth in their report, which is incorporated by reference in this prospectus and elsewhere in the registration statement. Our financial statements are incorporated by reference in reliance on Ernst & Young LLP’s report, given on their authority as experts in accounting and auditing.

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PART II. II

INFORMATION NOT REQUIRED IN THE PROSPECTUS

The following table sets forth allis an estimate of the expenses (all of which are to be paid by the Registrant, other than estimated underwriting discounts and commissions,registrant) that we may incur in connection with this offering. All amounts shown are estimates except for the SEC registration fee and the FINRA filing fee.securities being registered hereby.

Section 102(b)(7)Subsection (a) of the Delaware General Corporation Law (the “DGCL”) allows a corporation to provide in its certificate of incorporation that a director of the corporation will not be personally liable to the corporation or its stockholders for monetary damages for breach of fiduciary duty as a director, except where the director breached the duty of loyalty, failed to act in good faith, engaged in intentional misconduct or knowingly violated a law, authorized the payment of a dividend or approved a stock repurchase in violation of Delaware corporate law or obtained an improper personal benefit.

Section 145 of the General Corporation Law of the State of Delaware, or the DGCL, (“Section 145”) provides thatempowers a Delaware corporation mayto indemnify any person who was or is a party or who is threatened to be made a party to any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative (other than an action by or in the right of suchthe corporation), by reason of the fact that suchthe person is or was ana director, officer, director, employee or agent of suchthe corporation, or is or was serving at the request of suchthe corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or enterprise. The indemnity may includeother enterprise, against expenses (including attorneys’ fees), judgments, fines and amounts paid in settlement actually and reasonably incurred by suchthe person in connection with such action, suit or proceeding provided suchif the person acted in good faith and in a manner hethe person reasonably believed to be in or not opposed to the corporation’s best interests of the corporation, and, with respect to any criminal action or proceeding, had no reasonable cause to believe that his or herthe person’s conduct was illegal. A Delawareunlawful.

Subsection (b) of Section 145 empowers a corporation mayto indemnify any personsperson who are, werewas or areis a party or is threatened to be made a party to any threatened, pending or completed action or suit by or in the right of the corporation to procure a judgment in its favor by reason of the fact that the person acted in any of the capacities set forth above, against expenses (including attorneys’ fees) actually and reasonably incurred by the person in connection with the defense or settlement of such action or suit if the person acted in good faith and in a manner the person reasonably believed to be in or not opposed to the best interests of the corporation, except that no indemnification shall be made in respect of any claim, issue or matter as to which such person shall have been adjudged to be liable to the corporation unless and only to the extent that the Court of Chancery or the court in which such action or suit was brought shall determine upon application that, despite the adjudication of liability but in view of all the circumstances of the case, such person is fairly and reasonably entitled to indemnity for such expenses which the Court of Chancery or wassuch other court shall deem proper.

Section 145 further provides that to the extent a director or officer employeeof a corporation has been successful on the merits or agentotherwise in the defense of another corporationany action, suit or enterprise. The indemnity may include proceeding referred to in subsections (a) and (b) of Section 145, or in defense of any claim, issue or matter therein, such person shall be indemnified against

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expenses (including attorneys’ fees) actually and reasonably incurred by such person in connection withtherewith; that indemnification provided for by Section 145 shall not be deemed exclusive of any other rights to which the defenseindemnified party may be entitled; and the indemnification provided for by Section 145 shall, unless otherwise provided when authorized or settlement of such action or suit, provided suchratified, continue as to a person acted in good faith and in a manner he reasonably believedwho has ceased to be in or not opposed to the corporation’s best interests, provided that no indemnification is permitted without judicial approval if thea director, officer, director, employee or agent is adjudged to be liableand shall inure to the corporation. Where an officer or director is successful on the merits or otherwise in the defensebenefit of any action referred to above, the corporation must indemnify him against the expenses which such officer or director has actuallyperson’s heirs, executors and reasonably incurred.

administrators. Section 145 further authorizes aalso empowers the corporation to purchase and maintain insurance on behalf of any person who is or was a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise against any liability asserted against himsuch person and incurred by himsuch person in any such capacity, or arising out of his status as such, whether or not the corporation would otherwise have the power to indemnify himsuch person against such liabilities under Section 145.

Section 102(b)(7) of the DGCL provides that a corporation’s certificate of incorporation may contain a provision eliminating or limiting the personal liability of a director to the corporation or its stockholders for monetary damages for breach of fiduciary duty as a director, provided that such provision shall not eliminate or limit the liability of a director (i) for any breach of the director’s duty of loyalty to the corporation or its stockholders, (ii) for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (iii) under Section 174 of the DGCL, or (iv) for any transaction from which the director derived an improper personal benefit.

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Our amended and restated certificate of incorporation provides that to the fullest extent permitted by the DGCL, none of our directors shall be liable to our company or our stockholders for monetary damages arising from a breach of fiduciary duty owed to our company or our stockholders. In addition, our amended and restated bylaws provide that we must indemnify our directors and officers to the fullest extent authorized by the DGCL and must also pay expenses incurred in defending any such proceeding in advance of its final disposition upon delivery of an undertaking, by or on behalf of an indemnified person, to repay all amounts so advanced if it should be determined ultimately that such person is not entitled to be indemnified under this section or otherwise.

We have entered into indemnification agreements with each of our directors and executive officers in which we have agreed to indemnify, defend and hold harmless, and also advance expenses as incurred, to the fullest extent permitted under applicable law, from damage arising from the fact that such person is or was an officer or director of our company or our subsidiaries.

The indemnification rights set forth above shall not be exclusive of any other right which an indemnified person may have or hereafter acquire under any statute, our amended and restated certificate of incorporation, our amended and restated bylaws, any agreement, any vote of stockholders or disinterested directors or otherwise.

We expect to maintain standard policies of insurance that provide coverage (1) to our directors and officers against loss rising from claims made by reason of breach of duty or other wrongful act and (2) to us with respect to indemnification payments that we may make to such directors and officers.

The Registrant hasWe have purchased and intendsintend to maintain insurance on behalf of the RegistrantContraFect and any person who is or was a director or officer against any loss arising from any claim asserted against him or her and incurred by him or her in that capacity, subject to certain exclusions and limits of the amount of coverage.

(a)Exhibits

A list of exhibits filed with this registration statement on Form S-3 is set forth on the Exhibit Index and is incorporated herein by reference.

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(a) The undersigned Registrantregistrant hereby undertakes:

(1) To file, during any period in which offers or sales are being made, apost-effective amendment to this registration statement:

(i) toTo include any prospectus required by Section 10(a)(3) of the Securities Act;Act of 1933;

(ii) toTo reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recentpost-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered)statement; and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20 percent change in the maximum aggregate offering price set forth in the “Calculation of Registration Fee” table in the effective registration statement;

(iii) toTo include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement;

provided,however, that paragraphs (a)(1)(i), (a)(1)(ii), and (a)(1)(iii) above do not apply if the information required to be included in apost-effective amendment by those paragraphs is contained in reports filed with or furnished to the Commission by the Registrantregistrant pursuant to Sectionsection 13 or Sectionsection 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is a part of the registration statement.

(2) That, for the purpose of determining any liability under the Securities Act of 1933, each suchpost-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initialbona fide offering thereof.

(3) To remove from registration by means of apost-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

(4)(5) That, for the purpose of determining liability under the Securities Act of 1933 to any purchaser:

(i) each(A) Each prospectus filed by the Registrantregistrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in the registration statement; and

(ii) each(B) Each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5), or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(1)(i), (vii), or (x) for the purpose of providing the information required by Sectionsection 10(a) of the Securities Act of 1933 shall be deemed to be part of and included in the registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which thethat prospectus relates, and the offering of such securities at that time shall be deemed to be the initialbona fide offering thereof.Provided,however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such effective date.

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(5)(6) That, for the purpose of determining liability of the Registrantregistrant under the Securities Act of 1933 to any purchaser in the initial distribution of the securities, thesecurities:

The undersigned Registrantregistrant undertakes that in a primary offering of securities of the undersigned Registrantregistrant pursuant to this registration statement, regardless of the underwriting method used to sell the

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securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned Registrantregistrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

(i) anyAny preliminary prospectus or prospectus of the undersigned Registrantregistrant relating to the offering required to be filed pursuant to Rule 424;

(ii) anyAny free writing prospectus relating to the offering prepared by or on behalf of the undersigned Registrantregistrant or used or referred to by the undersigned Registrant;registrant;

(iii) theThe portion of any other free writing prospectus relating to the offering containing material information aboutprepared by or on behalf of the undersigned Registrantregistrant or its securities provided by or on behalf of the undersigned Registrant;registrant; and

(iv) anyAny other communicationcommunications that is an offer in the offering made by the undersigned Registrantregistrant to the purchaser.

(6) That,(b) The undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act of 1933, each filing of the Registrant’sregistrant’s annual report pursuant to Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan’s annual report pursuant to Sectionsection 15(d) of the Securities Exchange Act of 1934) that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initialbona fide offering thereof.

(7) To supplement the prospectus, after the expiration of the subscription period to set forth the results of the subscription offer, the transactions by the underwriters during the subscription period, the amount of unsubscribed securities to be purchased by the underwriters, and the terms of any subsequent reoffering thereof. If any public offering by the underwriters is to be made on terms differing from those set forth on the cover page of the prospectus, apost-effective amendment will be filed to set forth the terms of such offering.

(8) (i) To use its best efforts to distribute prior to the opening of bids, to prospective bidders, underwriters, and dealers, a reasonable number of copies of a prospectus which at that time meets the requirements of Section 10(a) of the Act, and relating to the securities offered at competitive bidding, as contained in the registration statement, together with any supplements thereto, and (ii) to file an amendment to the registration statement reflecting the results of bidding, the terms of the reoffering and related matters to the extent required by the applicable form, not later than the first use, authorized by the issuer after the opening of bids, of a prospectus relating to the securities offered at competitive bidding, unless no further public offering of such securities by the issuer and no reoffering of such securities by the purchasers is proposed to be made.

(9) To file an application for the purpose of determining the eligibility of the trustee to act under subsection (a) of Section 310 of the Trust Indenture Act in accordance with the rules and regulations prescribed by the Commission under Section 305(b)(2) of the Trust Indenture Act.

(10) That, insofar(h) Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the Registrantregistrant pursuant to the foregoing provisions, or otherwise, the Registrantregistrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the Registrantregistrant of expenses incurred or paid by a director, officer or controlling person of the Registrantregistrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the Registrantregistrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.

(j) The undersigned registrant hereby undertakes to file an application for the purpose of determining the eligibility of the trustee to act under subsection (a) of Section 310 of the Trust Indenture Act (the “Act”) in accordance with the rules and regulations prescribed by the SEC under section 305(b)(2) of the Act.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of New York, State ofYonkers, New York, on September 4, 2015.the 1st day of June, 2016.

EachPOWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints JULIA P. GREGORYSteven C. Gilman and MICHAEL MESSINGER, and eachMichael H. Messinger, or either of them, any of whom may act without the joinder of the other, as his or her true and lawfulattorney-in-fact attorneys-in-fact and agent,agents, with full power of substitution and resubstitution, for him or her and in his or her name, place and stead, in any and all capacities, to file and sign any and all amendments, (includingincluding post-effective amendments) to this registration statement amendments and any registration statement (including any amendment thereto)for the same offering that is to be effective upon filing pursuant tounder Rule 462(b) underof the Securities Act, and to file the same, with all exhibits thereto, and all other documents in connection therewith,this registration statement, with the Securities and Exchange Commission, granting unto saidattorneys-in-fact and agents, full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith as fully to all intents and purposes as he or she might or wouldcould do in person, hereby ratifying and confirming all that saidattorneys-in-fact and agents, or any of them of their or his substitute andor substitutes may lawfully do or cause to be done by virtue hereof. This power of attorney shall be governed by and construed with the laws of the State of Delaware and applicable federal securities laws.

Pursuant to the requirements of the Securities Act of 1933, as amended, this registration statement has been signed below by the following persons on behalf of the registrant in the capacities and on the dates indicated.

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EXHIBIT INDEX

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