STOCKHOLDER PROPOSALS

Stockholder proposals intended to be included in the 2017 annual meeting proxy materials must be received by the Secretary of the Company no later than February 1, 2017, or otherwise as permitted by applicable law (the “ Proxy Deadline ”). The form and substance of these proposals must satisfy the requirements established by the Company’s Bylaws and the SEC, and the timing for the submission of any such proposals may be subject to change as a result of changes in SEC rules and regulations.

Additionally, stockholders who intend to present a stockholder proposal at the 2017 annual meeting must provide the Secretary of the Company with written notice of the proposal not fewer than 90 nor more than 120 days prior to the anniversary date of the 2016 annual meeting,  provided, however , that if the 2017 annual meeting date is more than 30 days before or after the anniversary date of the 2016 annual meeting, then stockholders must provide notice on or before 10 days after the day on which the date of the 2017 annual meeting is first disclosed in a public announcement. Notice must be tendered in the proper form prescribed by our Bylaws. Proposals not meeting the requirements set forth in our Bylaws will not be entertained at the meeting.

Additionally, any stockholder seeking to recommend a director candidate or any director candidate who wishes to be considered by the Nominating and Governance Committee, the committee that recommends a slate of nominees to the Board for election at each annual meeting, must provide the Secretary of the Company with a completed and signed biographical questionnaire on or before the Proxy Deadline. Stockholders can obtain a copy of this questionnaire from the Secretary of the Company upon written request. The Nominating and Governance Committee is not required to consider director candidates received after this date or without the required questionnaire. The Nominating and Governance Committee will consider all director candidates who comply with these requirements and will evaluate these candidates using the criteria described above under the caption, “Nomination of Directors.” Director candidates who are then approved by the Board will be included in the Company’s proxy statement for that annual meeting.

DELIVERY OF PROXY MATERIALS

Our Annual Report to stockholders for the fiscal year ended December 31, 2015, including audited financial statements and the notes thereto, accompanies this Proxy Statement. Copies of our Annual Report on Form 10-K for fiscal 2015 and the exhibits thereto are available from the Company without charge upon written request of a

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stockholder. Copies of these materials are also available online through the SEC at  www.sec.gov . The Company may satisfy SEC rules regarding delivery of proxy materials, including the Proxy Statement, Annual Report and Notice, by delivering a single Notice and, if applicable, a single set of proxy materials to an address shared by two or more Company stockholders. This delivery method can result in meaningful cost savings for the Company. In order to take advantage of this opportunity, the Company may deliver only one Notice and, if applicable, a single set of proxy materials to multiple stockholders who share an address, unless contrary instructions are received prior to the mailing date. Similarly, if you share an address with another stockholder and have received multiple copies of our Notice and/or other proxy materials, you may write or call us at the address and phone number below to request delivery of a single copy of the Notice and, if applicable, other proxy materials in the future. We undertake to deliver promptly upon written or oral request a separate copy of the Notice and, if applicable, other proxy materials, as requested, to a stockholder at a shared address to which a single copy of the Notice and/or other proxy materials was delivered. If you hold stock as a record stockholder and prefer to receive separate copies of a Notice and, if applicable, other proxy materials either now or in the future, please contact the Company’s Investor Relations department at 257 Simarano Drive, Suite 101, Marlborough, MA 01752 or by telephone at (508) 929-3646. If your stock is held through a brokerage firm or bank and you prefer to receive separate copies of a Notice and, if applicable, other proxy materials either now or in the future, please contact your brokerage firm or bank.

EACH STOCKHOLDER IS URGED TO COMPLETE, DATE, SIGN AND PROMPTLY RETURN

THE ENCLOSED PROXY.

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APPENDIX A

RXi PHARMACEUTICALS CORPORATION

EMPLOYEE STOCK PURCHASE PLAN

SECTION 1.  PURPOSE OF PLAN

The RXi Pharmaceuticals Corporation Employee Stock Purchase Plan (the “Plan”) is intended to enable eligible employees of RXi Pharmaceuticals Corporation (“RXi”) and such of its Subsidiaries as the Board of Directors of RXi (the “Board”) may from time to time designate (RXi and such Subsidiaries being hereinafter referred to as the “Company”) to use payroll deductions to purchase shares of common stock, $0.0001 par value of RXi (such common stock being hereafter referred to as “Stock”), and thereby acquire an interest in the future of RXi. For purposes of the Plan, a “Subsidiary” is any corporation that would be treated as a subsidiary of RXi under Section 424(f) of the Internal Revenue Code of 1986, as amended (the “Code”). The Plan is intended to qualify under Section 423 of the Code and will be construed accordingly.

SECTION 2.  RIGHT TO PURCHASE STOCK

Subject to adjustment pursuant to Section 16 of this Plan, the maximum aggregate number of shares of Stock available for sale pursuant to the exercise of options (“Stock Rights”) granted under the Plan to employees of the Company (“Employees”) who meet the eligibility requirements set forth in Section 3 hereof (“Eligible Employees”) is the lesser of (a) 5,000 shares increased on each anniversary of the adoption of the Plan by one percent (1%) of the total shares of Common Stock then outstanding and (b) 11,333 shares. The Stock to be delivered upon exercise of Stock Rights under the Plan may be either shares of authorized but unissued Stock or shares of reacquired Stock, as the Board may determine. If any Stock Right granted under the Plan shall expire or terminate for any reason without having been exercised in full or shall cease for any reason to be exercisable in whole or in part, the unpurchased Stock subject to such Stock Right shall again be available for sale pursuant to the exercise of Stock Rights under the Plan.

SECTION 3.  ELIGIBLE EMPLOYEES

Subject to the exceptions and limitations set forth below, each Employee will be eligible to participate in the Plan on or after the first day of the month following his or her date of hire with respect to an Purchase Period beginning on or after such date.

(a) Any Employee who immediately after the grant of a Stock Right would own (or pursuant to Section 423(b)(3) of the Code would be deemed to own) stock possessing 5% or more of the total combined voting power or value of all classes of stock of the employer corporation or of its parent or subsidiary corporation, as defined in Section 424 of the Code, will not be eligible to receive a Stock Right to purchase Stock pursuant to the Plan.

(b) No Employee will be granted a Stock Right under the Plan that would permit his or her rights to purchase shares of stock under all employee stock purchase plans of the employer corporation and parent and subsidiary corporations to accrue at a rate that exceeds $25,000 (or such other maximum as may be prescribed from time to time under Section 423 of the Code or any successor provision) in fair market value of such stock (determined at the time the Stock Right is granted) for any calendar year during which any such Stock Right granted to such Employee is outstanding, as provided in Section 423 of the Code.

SECTION 4.  METHOD OF PARTICIPATION

Unless otherwise determined by the Compensation Committee of the Board (the “Committee”), the “Purchase Periods” shall be the six-month periods commencing January 1 and ending June 30 and commencing July 1 and ending December 31 of each year. Except as provided in Section 11, each person who will be an Eligible Employee on the first day of any Purchase Period may elect to participate in the Plan by executing and delivering, by such deadline prior thereto as the Committee may specify (the “Enrollment Deadline”), a payroll

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deduction authorization in accordance with Section 5. Such Employee will thereby become a participant (“Participant”) on the first day of such Purchase Period and will remain a Participant until his or her participation is terminated as provided in the Plan.

SECTION 5.  PAYROLL DEDUCTION

Each payroll deduction authorization will request withholding at a percentage of Compensation per payroll period within a range specified by the Committee for the applicable Purchase Period. Withholding will be accomplished by means of payroll deductions from payroll periods ending in the Purchase Period. For purposes of the Plan, “Compensation” means wages, tips and other compensation reported on a Participant’s Form W-2, plus compensation that is not currently includible in the Participant’s gross income by reason of the application of Code Sections 125, 132(f)(4), 402(e)(3), 401(k), 402(h)(1)(B), 414(h), 403(b), or 457(b), and excluding reimbursements or other expense allowances, fringe benefits (cash or non-cash), moving expenses, deferred compensation (other than deferrals permitted by reason of one of the Code sections mentioned above), welfare benefits. Compensation shall include only that compensation that is actually paid to the Participant during the applicable Plan Year and while the employee is a Participant in the Plan. A Participant may not change his or her withholding rate once during a Purchase Period. However, a Participant may change his or her withholding rate for subsequent Purchase Periods by filing a new payroll deduction authorization with the Company on or before the Enrollment Deadline for the Purchase Period for which the change is to be effective. In addition, a Participant may cancel his or her participation in a Purchase Period as set forth in Section 11. All amounts withheld in accordance with a Participant’s payroll deduction authorization will be credited to a withholding account maintained in the Participant’s name on the books of the Company. Amounts credited to the withholding account will not be required to be set aside in trust or otherwise segregated from the Company’s general assets.

SECTION 6.  GRANT OF STOCK RIGHTS

Each person who is a Participant on the first day of a Purchase Period will be granted, as of such day and for such Purchase Period, a Stock Right entitling the Participant to acquire shares of Stock equal in number to the lesser of:

(a) the whole number (disregarding any fractional share amount) determined by dividing $12,500 by the fair market value of one share of Stock on the first day of the Purchase Period; and

(b) the whole number (disregarding any fractional share amount) determined by dividing (i) the balance credited to the Participant’s withholding account on the last day of the Purchase Period, by (ii) the purchase price per share of the Stock determined under Section 7.

The Committee will reduce, on a substantially proportionate basis, the number of shares of Stock purchasable by each Participant upon exercise of his or her Stock Right for a Purchase Period in the event that the number of shares then available under the Plan is insufficient. Stock Right grants under this Section 6 will be automatic and need not be separately documented.

SECTION 7.  PURCHASE PRICE

The purchase price of Stock issued pursuant to the exercise of a Stock Right will be 90% of the fair market value of the Stock on (a) the date of grant of the Stock Right or (b) the date on which the Stock Right is deemed exercised, whichever is less. If the shares of Stock are traded on a national exchange or trading system (including the NASDAQ National Market System and the OTC Markets Group), the fair market value for any day will mean the reported closing price of the Stock for such day; provided , that if such day is not a trading day, fair market value will mean the reported closing price of the Stock for the next preceding day which is a trading day. If the shares of Stock are not traded on an exchange or trading system, the fair market value of such Stock on such date will be established in a manner determined in good faith by the Board.

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SECTION 8.  EXERCISE OF STOCK RIGHTS

If any Employee is a Participant in the Plan on the last day of a Purchase Period, he or she will be deemed to have exercised the Stock Right granted to him or her for that Purchase Period. Upon such exercise, the Company will apply the balance of the Participant’s withholding account to the purchase of the number of whole shares of Stock determined under Section 6 and as soon as practicable thereafter will evidence the transfer of shares of Stock or will deliver the shares of Stock to the Participant and will return to him or her the balance, if any, of his or her withholding account in excess of the total purchase price of the shares so issued; provided , that if the balance left in the account consists solely of an amount equal to the value of a fractional share it will be retained in the account and carried over to the next Purchase Period.

Notwithstanding anything herein to the contrary, the Company’s obligation to issue and deliver shares of Stock under the Plan will be subject to the approval required of any governmental authority in connection with the authorization, issuance, sale or transfer of said shares, to any requirements of any national securities exchange applicable thereto, and to compliance by the Company with other applicable legal requirements in effect from time to time.

SECTION 9.  INTEREST

No interest will be payable on withholding accounts.

SECTION 10.  TAXES

Payroll deductions are made on an after-tax basis. If the Company determines that the exercise of a Stock Right or the disposition of shares following the exercise of a Stock Right could result in employment tax liability, the Company may, as a condition of exercise, make such provision as it deems necessary to provide for the remittance by the Participant of employment taxes required to be paid in connection with such exercise or disposition of shares.

SECTION 11.  CANCELLATION AND WITHDRAWAL

A Participant who holds a Stock Right under the Plan may at any time prior to exercise thereof under Section 8 cancel all (but not less than all) of his or her Stock Right by written notice delivered to the Company. Upon such cancellation, the balance in the Participant’s withholding account will be returned to the Participant.

A Participant may terminate his or her payroll deduction authorization as of any date by written notice delivered to the Company and will thereby cease to be a Participant as of such date. Any Participant who voluntarily terminates his or her payroll deduction authorization prior to the last day of a Purchase Period will be deemed to have canceled his or her Stock Right.

A Participant who makes a hardship withdrawal from a Company savings plan qualifying under Section 401(k) of the Code (a “401(k) Plan”) will be deemed to have terminated his or her payroll deduction authorization as of the date of such hardship withdrawal, will cease to be a Participant as of such date, and will be deemed to have canceled his or her Stock Right. An Employee who has made a hardship withdrawal from a 401(k) Plan will not be permitted to participate in the Plan until the first Purchase Period that begins six months after the date of his or her hardship withdrawal.

SECTION 12.  RESTRICTIONS ON TRANSFER

All shares of Stock purchased under the Plan will be subject to a restriction prohibiting the transfer of such shares of Stock from the account where such shares of Stock are initially held until such shares are sold through the Plan’s administrator, custodian, or record keeper. For the avoidance of doubt, this restriction will remain in effect following the termination of a Participant’s employment with the Company.

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SECTION 13.  TERMINATION OF EMPLOYMENT

Except as otherwise provided in Section 14, upon the termination of a Participant’s employment with the Company for any reason, he or she will cease to be a Participant, any Stock Right held by him or her under the Plan will be deemed canceled, the balance of his or her withholding account will be returned, and he or she will have no further rights under the Plan.

SECTION 14.  DEATH OF PARTICIPANT

A Participant may elect that if death should occur during a Purchase Period the balance, if any, of the Participant’s withholding account at the time of death will be applied at the end of the Purchase Period to the exercise of the Participant’s Stock Right and the shares thereby purchased under the Stock Right (plus any balance remaining in the Participant’s withholding account) will be delivered to the Participant’s beneficiary or beneficiaries. Except as otherwise determined by the Committee (which may establish a procedure for the designation of beneficiaries under the Plan), a Participant’s beneficiary(ies) for purposes of the Plan will be the Participant’s estate.

SECTION 15.  EQUAL RIGHTS; PARTICIPANT’S RIGHTS NOT TRANSFERABLE

All Participants granted Stock Rights under the Plan with respect to any Purchase Period will have the same rights and privileges. Each Participant’s rights and privileges under any Stock Right granted under the Plan will be exercisable during the Participant’s lifetime only by him or her and except as provided in Section 14 above may not be sold, pledged, assigned, or transferred in any manner. In the event any Participant violates or attempts to violate the terms of this Section, any Stock Rights held by him or her may be terminated by the Company and, upon return to the Participant of the balance of his or her withholding account, all of the Participant’s rights under the Plan will terminate.

SECTION 16.  EMPLOYMENT RIGHTS

Nothing contained in the provisions of the Plan will be construed as giving to any Employee the right to be retained in the employ of the Company or as interfering with the right of the Company to discharge any Employee at any time.

SECTION 17.  CHANGE IN CAPITALIZATION, MERGER

In the event of any change in the outstanding Stock of RXi by reason of a stock dividend, split-up, recapitalization, merger, consolidation, reorganization, or other capital change, the aggregate number and type of shares available under the Plan, the number and type of shares under Stock Rights granted but not exercised, the maximum number and type of shares purchasable under a Stock Right, and the Stock Right price will be appropriately adjusted.

In the event of a sale of all or substantially all of the Stock or a sale of all or substantially all of the assets of RXi, or a merger or similar transaction in which RXi is not the surviving corporation or which results in the acquisition of RXi by another person, the Board will (a) if RXi is merged with or acquired by another corporation, provide that each outstanding Stock Right will be assumed or a substitute Stock Right granted by the acquiror or successor corporation or a parent or subsidiary of the acquiror or successor corporation, (b) cancel each Stock Right and return the balances in Participants’ withholding accounts to the Participants, or (c) pursuant to Section 19, end the Purchase Period on or before the date of the proposed sale or merger.

SECTION 18.  ADMINISTRATION OF PLAN

The Plan will be administered by the Committee, which will have the right to determine any questions which may arise regarding the interpretation and application of the provisions of the Plan and to make, administer, and interpret such rules and regulations as it will deem necessary or advisable. References in the Plan to the Committee will include the Committee’s delegates to the extent of any delegation by the Committee to such delegates of administrative responsibilities hereunder.

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The Committee may specify the manner in which employees are to provide notices and payroll deduction authorizations. Notwithstanding any requirement of “written notice” herein, the Committee may permit employees to provide notices and payroll deduction authorizations electronically.

SECTION 19.  AMENDMENT AND TERMINATION OF PLAN

RXi reserves the right at any time or times to amend the Plan to any extent and in any manner it may deem advisable, by vote of the Board; provided, that any amendment that would be treated as the adoption of a new plan for purposes of Section 423 of the Code and the regulations thereunder will have no force or effect unless approved by the stockholders of RXi within twelve months before or after its adoption.

The Plan may be suspended or terminated at any time by the Board. In connection therewith, the Board may either cancel outstanding Stock Rights or continue them and provide that they will be exercisable either at the end of the applicable Purchase Period as determined under Section 4 above or on such earlier date as the Board may specify (in which case such earlier date will be treated as the last day of the applicable Purchase Period).

SECTION 20.  APPROVAL OF STOCKHOLDERS

The Plan and the exercisability of Stock Rights granted hereunder will be subject to the approval of the stockholders of RXi obtained within twelve months before or after the date the Plan is adopted by the Board.

Proposed Amendment to RXi Pharmaceuticals Corporation Employee Stock Purchase Plan

Section 2 of the RXi Pharmaceuticals Corporation Employee Stock Purchase Plan is hereby amended and restated as follows and all related Plan information shall be amended accordingly:

SECTION 2.  RIGHT TO PURCHASE STOCK

Subject to adjustment pursuant to Section 16 of this Plan, the maximum aggregate number of shares of Stock available for sale pursuant to the exercise of options (“Stock Rights”) granted under the Plan to employees of the Company (“Employees”) who meet the eligibility requirements set forth in Section 3 hereof (“Eligible Employees”) is 511,333. The Stock to be delivered upon exercise of Stock Rights under the Plan may be either shares of authorized but unissued Stock or shares of reacquired Stock, as the Board may determine. If any Stock Right granted under the Plan shall expire or terminate for any reason without having been exercised in full or shall cease for any reason to be exercisable in whole or in part, the unpurchased Stock subject to such Stock Right shall again be available for sale pursuant to the exercise of Stock Rights under the Plan.

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APPENDIX B

RXi Pharmaceuticals Corporation

2012 LONG TERM INCENTIVE PLAN

1. DEFINED TERMS

Exhibit A, which is incorporated by reference, defines the terms used in the Plan and sets forth certain operational rules related to those terms.

2. PURPOSE

The Plan has been established to advance the interests of the Company by providing for the grant to Participants of Stock-based incentive Awards and other Awards.

3. ADMINISTRATION

The Administrator has discretionary authority, subject only to the express provisions of the Plan, to interpret the Plan; determine eligibility for and grant Awards; determine, modify or waive the terms and conditions of any Award; prescribe forms, rules and procedures; and otherwise do all things necessary to carry out the purposes of the Plan. In the case of any Performance Award intended to qualify as exempt performance-based compensation under Section 162(m), the Administrator will exercise its discretion consistent with qualifying the Award for that exemption. Determinations of the Administrator made under the Plan will be conclusive and will bind all parties.

4. LIMITS ON AWARDS UNDER THE PLAN

(a) Number of Shares . The maximum number of shares of Stock that may be delivered upon satisfaction of Equity Awards under the Plan shall be 300,000 shares of Stock. Up to the total number of shares of Stock set forth in the preceding sentence may be issued in satisfaction of ISOs, but nothing in this Section 4(a) shall be construed as requiring that any, or any fixed number of, ISOs be awarded under the Plan. The number of shares of Stock delivered in satisfaction of Equity Awards shall, for purposes of this Section 4(a), be determined net of shares of Stock withheld by the Company in payment of the exercise price of the Award or in satisfaction of tax withholding requirements with respect to the Award and, for the avoidance of doubt, without including any shares of Stock underlying Awards settled in cash or which otherwise expire or become unexercisable without having been exercised or are forfeited to or repurchased by the Company due to failure to vest. The limits set forth in this Section 4(a) shall be construed to comply with Section 422. To the extent consistent with the requirements of Section 422 and with other applicable legal requirements (including applicable stock exchange requirements, if any), Stock issued under Substitute Awards shall not reduce the number of shares available for Awards under the Plan. The shares which may be delivered under Substitute Awards shall be in addition to the limitations set forth in this Section 4(a) on the number of shares available for issuance under the Plan, and such Substitute Awards shall not be subject to the per Participant Award limits described in Section 4(c) below.

(b) Type of Shares . Shares of Stock delivered by the Company under the Plan may be authorized but unissued Stock or previously issued Stock acquired by the Company. No fractional shares of Stock will be delivered under the Plan.

(c) Section 162(m) Limits . Solely for purposes of Section 162(m), the maximum number of shares of Stock for which Stock Options may be granted to any person in any calendar year and the maximum number of shares of Stock subject to SARs granted to any person in any calendar year will each be one half of the total number of shares authorized for issuance pursuant to Section 4(a) of the Plan (the “162(m) Limit”). The maximum number of shares of Stock subject to other Equity Awards granted to any person in any calendar year will be equal to the 162(m) Limit. The maximum amount payable to any person in any twelve (12) month period under Cash Awards will be $1,000,000, which limitation, with respect to any Cash Awards for which payment is deferred in

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accordance with Section 6(c)(2), shall be applied by assuming that payment of the Award was made at the time it would have been paid absent the deferral. The foregoing provisions will be construed in a manner consistent with Section 162(m).

5. ELIGIBILITY AND PARTICIPATION

The Administrator will select Participants from among those key Employees and directors of, and consultants and advisors to, the Company or its Affiliates who, in the opinion of the Administrator, are in a position to make a significant contribution to the success of the Company and its Affiliates; provided , that, subject to such express exceptions, if any, as the Administrator may establish, eligibility for Equity Awards shall be further limited to those persons as to whom the use of a Form S-8 registration statement is permissible. Eligibility for ISOs is limited to employees of the Company or of a “parent corporation” or “subsidiary corporation” of the Company as those terms are defined in Section 424 of the Code. Eligibility for Stock Options other than ISOs is limited to individuals described in the first sentence of this Section 5 who are providing direct services on the date of grant of the Sock Option to the Company or to a subsidiary of the Company that would be described in the first sentence of Treas. Regs. §1.409A-1(b)(5)(iii)(E).

6. RULES APPLICABLE TO AWARDS

(a) In General

(1) Award Provisions . The Administrator will determine the terms of all Awards, subject to the limitations provided herein. By accepting (or, under such rules as the Administrator may prescribe, being deemed to have accepted) an Award, the Participant agrees to the terms of the Award and the Plan. The Administrator will determine whether Equity Awards are settled in shares of Stock or cash or whether the settlement or payment of Awards shall be subject to deferral. Notwithstanding any provision of this Plan to the contrary, Substitute Awards may contain terms and conditions that are inconsistent with the terms and conditions specified herein, as determined by the Administrator.

(2) Term of Plan . No Awards may be made after the tenth anniversary of the date that this Plan is first adopted by the Board of Directors of the Company, but previously granted Awards may continue beyond that date in accordance with their terms.

(3) Transferability . Neither ISOs nor, except as the Administrator otherwise expressly provides in accordance with the second sentence of this Section 6(a)(3), other Awards may be transferred other than by will or by the laws of descent and distribution, and during a Participant’s lifetime ISOs (and, except as the Administrator otherwise expressly provides in accordance with the second sentence of this Section 6(a)(3), other Equity Awards requiring exercise) may be exercised only by the Participant. The Administrator may permit Equity Awards other than ISOs to be transferred by gift, subject to applicable securities and other laws and such limitations as the Administrator may impose.

(4) Vesting, Etc. The Administrator shall determine the time or times at which an Equity Award will vest or become exercisable and the terms on which an Equity Award requiring exercise will remain exercisable. Without limiting the foregoing, the Administrator may at any time accelerate the vesting or exercisability of an Equity Award, regardless of any adverse or potentially adverse tax or other consequences resulting from such acceleration. Unless the Administrator expressly provides otherwise, however, the following rules will apply if a Participant’s Employment ceases: immediately upon the cessation of the Participant’s Employment, each Award requiring exercise that is then held by the Participant or by the Participant’s permitted transferees, if any, will cease to be exercisable and will terminate, and all other Awards that are then held by the Participant or by the Participant’s permitted transferees, if any, to the extent not already vested will be forfeited, except that:

(A) subject to (B) and (C) below, all Stock Options and SARs held by the Participant or the Participant’s permitted transferees, if any, immediately prior to the cessation of the Participant’s Employment, to the

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extent then exercisable, will remain exercisable for the lesser of (i) a period of three months or (ii) the period ending on the latest date on which such Stock Option or SAR could have been exercised without regard to this Section 6(a)(4), and will thereupon terminate;

(B) all Stock Options and SARs held by a Participant or the Participant’s permitted transferees, if any, immediately prior to the cessation of Participant’s Employment due to death, to the extent then exercisable, will remain exercisable for the lesser of (i) the one year period ending with the first anniversary of the Participant’s death or (ii) the period ending on the latest date on which such Stock Option or SAR could have been exercised without regard to this Section 6(a)(4), and will thereupon terminate; and

(C) all Stock Options and SARs held by a Participant or the Participant’s permitted transferees, if any, immediately prior to the cessation of the Participant’s Employment will immediately terminate upon such cessation if the Administrator in its sole discretion determines that such cessation of Employment has resulted for reasons which cast such discredit on the Participant as to justify immediate termination of the Award or are otherwise determined by the Administrator to constitute cause.

(5) Recovery of Compensation; Other Terms

(A) Awards (whether or not vested or exercisable) held by a Participant are subject to forfeiture, termination and rescission, and a Participant will be obligated to return to the Company the value received with respect to Awards (including payments made and/or Stock delivered under an Award, and any gain realized on a subsequent sale or disposition of an Award or Stock delivered under an Award), in each case (i) to the extent provided by the Administrator in an Award agreement in connection with (A) a breach by the Participant of a non-competition, non-solicitation, confidentiality or similar covenant or agreement or (B) an overpayment to the Participant of incentive compensation due to inaccurate financial data, (ii) in accordance with Company policy relating to the recovery of erroneously-paid incentive compensation, as such policy may be amended and in effect from time to time, or (iii) as otherwise required by law or applicable stock exchange listing standards, including, without limitation, the Dodd-Frank Wall Street Reform and Consumer Protection Act.

(B) Each Participant, by accepting an Award pursuant to the Plan, agrees to return the full amount required under this Section 6(a)(5) at such time and in such manner as the Administrator shall determine in its sole discretion and consistent with applicable law. Neither the Administrator nor the Company will be responsible for any adverse tax or other consequences to a Participant that may arise in connection with this Section 6(a)(5). For the avoidance of doubt, in addition to any forfeiture or other restrictions imposed by the terms of an Award agreement, every Award issued under the Plan will be subject to potential forfeiture or “claw back” to the fullest extent called for by applicable federal or state law. In addition, to the extent provided by the Administrator, Shares received upon settlement, vesting or exercise of an Award may be subject to stock ownership guidelines or policies established by the Company with respect to its employees, directors and/or other service providers.

(6) Taxes . The Administrator will make such provision for the withholding of taxes as it deems necessary. The Administrator may, but need not, hold back shares of Stock from an Award or permit a Participant to tender previously owned shares of Stock in satisfaction of tax withholding requirements (but not in excess of the minimum withholding required by law).

(7) Dividend Equivalents, Etc. The Administrator may provide for the payment of amounts (on terms and subject to conditions established by the Administrator) in lieu of cash dividends or other cash distributions with respect to Stock subject to an Equity Award. Any entitlement to dividend equivalents or similar entitlements shall be established and administered either consistent with exemption from, or in compliance with, the requirements of Section 409A. In addition, any amounts payable in respect of Restricted Stock (or any other Award subject to any vesting condition) may be subject to such limits or restrictions or alternative terms as the Administrator may impose.

(8) Rights Limited . Nothing in the Plan will be construed as giving any person the right to be granted an Award or to continued employment or service with the Company or its Affiliates, or any rights as a

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stockholder except as to shares of Stock actually issued under the Plan. The loss of existing or potential profit in Awards will not constitute an element of damages in the event of termination of Employment for any reason, even if the termination is in violation of an obligation of the Company or any Affiliate to the Participant.

(9) Section 162(m)

(A) Awards Intended to Qualify for Performance-Based Compensation Exception. This Section 6(a)(9) applies to any Performance Award intended to qualify as exempt performance-based compensation under Section 162(m), as determined by the Administrator. In the case of any Performance Award to which this Section 6(a)(9) applies, (i) the Plan and such Award will be construed and administered to the maximum extent permitted by law in a manner consistent with qualifying the Award for such exemption, notwithstanding anything to the contrary in the Plan; (ii) the Administrator will preestablish, in writing and no later than 90 days after the commencement of the period of service to which the performance relates (or at such earlier time as is consistent with qualifying the Award for such exemption), one or more Performance Criteria applicable to such Award, the amount or amounts that will be payable or earned (subject to reduction as described below) if the Performance Criteria are achieved, and such other terms and conditions as the Administrator deems appropriate with respect to such Award; (iii) at the close of the applicable Performance Period, the Administrator will certify whether the applicable Performance Criteria have been attained; (iv) no amount will be paid under such Award unless the Performance Criteria applicable to the payment of such amount have been so certified, except as provided by the Administrator consistent with such exemption; and (v) the Administrator may, in its sole and absolute discretion (either in individual cases or in ways that affect more than one Participant), reduce the actual payment, if any, to be made under such Award to the extent consistent with such exemption.

(B) Certain Transition Awards. Awards intended to be exempt from the limitations of Section 162(m) will not be required to comply with the provisions of Section 6(a)(9)(A) if and to the extent they are eligible (as determined by the Administrator) for exemption from such limitations by reason of the transition relief set forth in Treas. Regs. §1.162-27(f)(4).

(10) Coordination with Other Plans . Awards under the Plan may be granted in tandem with, or in satisfaction of or substitution for, other Awards under the Plan or awards made under other compensatory plans or programs of the Company or its Affiliates. For example, but without limiting the generality of the foregoing, awards under other compensatory plans or programs of the Company or its Affiliates may be settled in Stock (including, without limitation, Unrestricted Stock) if the Administrator so determines, in which case the shares delivered shall be treated as awarded under the Plan (and shall reduce the number of shares thereafter available under the Plan in accordance with the rules set forth in Section 4). In any case where an award is made under another plan or program of the Company or its Affiliates and such award is intended to qualify for the performance-based compensation exception under Section 162(m), and such award is settled by the delivery of Stock or another Award under the Plan, the applicable Section 162(m) limitations under both the other plan or program and under the Plan shall be applied to the Plan as necessary (as determined by the Administrator) to preserve the availability of the Section 162(m) performance-based compensation exception with respect thereto.

(11) Section 409A . Each Award shall contain such terms as the Administrator determines, and shall be construed and administered, such that the Award either (i) qualifies for an exemption from the requirements of Section 409A, or (ii) satisfies such requirements.

(12) Fair Market Value . Except as otherwise expressly provided herein, in determining the fair market value of any share of Stock under the Plan, the Administrator shall make the determination in good faith on such basis as it deems appropriate, taking into account the requirements of Section 422 and Section 409A, to the extent applicable; provided , that unless otherwise determined by the Administrator, if the Stock is admitted to trading on an established securities exchange, “fair market value” shall be the closing price of a share of Stock on such date (or, if the Stock was not traded on such day, then the next preceding day on which the Stock was traded).

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(13) Certain Requirements of Corporate Law . Equity Awards shall be granted and administered consistent with the requirements of applicable Delaware law relating to the issuance of stock and the consideration to be received therefor, and with the applicable requirements of the stock exchanges or other trading systems or national market on which the Stock is listed or entered for trading, in each case as determined by the Administrator.

(b) Awards Requiring Exercise . Equity Awards requiring exercise will be subject to the provisions of this Section 6(b).

(1) Time and Manner of Exercise . Unless the Administrator expressly provides otherwise, an Award requiring exercise by the holder will not be deemed to have been exercised until the Administrator receives a notice of exercise (in form acceptable to the Administrator), which may be an electronic notice, signed (including electronic signature in form acceptable to the Administrator) by the appropriate person and accompanied by any payment required under the Award. If the Award is exercised by any person other than the Participant, the Administrator may require satisfactory evidence that the person exercising the Award has the right to do so.

(2) Exercise Price . The exercise price (or the base value from which appreciation is to be measured) of each Award requiring exercise shall be 100% (in the case of an ISO granted to a ten-percent shareholder within the meaning of subsection (b)(6) of Section 422, 110%) of the fair market value of the Stock (as provided in Section 6(a)(12)) subject to the Award, determined as of the date of grant, or such higher amount as the Administrator may determine in connection with the grant or as otherwise determined by the Administrator with respect to a Substitute Award.

(3) Payment of Exercise Price . Where the exercise of an Award is to be accompanied by payment, payment of the exercise price shall be by cash or check acceptable to the Administrator, or, if so permitted by the Administrator and if legally permissible, (i) through the delivery of unrestricted shares of Stock that have a fair market value equal to the exercise price, subject to such holding requirements, if any, as the Administrator may prescribe, (ii) through a broker-assisted exercise program acceptable to the Administrator, (iii) through the withholding of shares of Stock otherwise to be delivered upon exercise of the Award whose fair market value is equal to the aggregate exercise price of the Award being exercised, (iv) by other means acceptable to the Administrator, or (v) by any combination of the foregoing permissible forms of payment. The delivery of shares in payment of the exercise price under clause (i) above may be accomplished either by actual delivery or by constructive delivery through attestation of ownership, subject to such rules as the Administrator may prescribe.

(4) Maximum Term . Awards requiring exercise will have a maximum term not to exceed ten (10) years from the date of grant (or five (5) years from the date of grant in the case of an ISO granted to a ten-percent shareholder described in Section 6(b)(2) above); provided , that if an Award requiring exercise (other than an ISO) would otherwise expire as a result of expiration of the maximum term of such Award (i.e., ten (10) years from the date of grant or such shorter time period as set forth in an Award agreement), and at such time the Participant holding such Award is prohibited by applicable law or written Company policy applicable to similarly situated employees from engaging in any open-market sales of Stock, the maximum term of such Award will automatically extend to thirty (30) days following the date the Participant is no longer prohibited from engaging in such open-market sales.

(c) Cash Awards

(1) A Participant who is granted a Cash Award shall be entitled to a payment, if any, under the Award only if all conditions to payment have been satisfied in accordance with the Plan and the terms of the Award. The Administrator will determine the actual payment, if any, under each Cash Award. The Administrator may, in its sole and absolute discretion (but subject, for the avoidance of doubt, to Section 6(a)(9) of the Plan), after determining the amount that would otherwise be payable for a Performance Period with respect to a Cash Award that is a Performance Award, adjust (including to zero) the payment, if any, to be made under such

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Award. Cash Awards granted as Performance Awards under the Plan will be with respect to a Performance Period greater than one year, except as otherwise determined by the Administrator.

(2) The Administrator shall determine the payment dates for Cash Awards under the Plan. Except as otherwise determined by the Administrator, no payment shall be made under a Cash Award unless the Participant’s Employment continues through the date such Cash Award is paid. Payments hereunder are intended to fall under the short-term deferral exception to Section 409A and shall be construed and administered accordingly. Notwithstanding the foregoing, (i) if the documentation establishing the Cash Award provides a specified and objectively determinable payment date or schedule that satisfies the requirements of Section 409A, payment under an Award may be made in accordance with such date or schedule, and (ii) the Administrator may, but need not, permit a Participant to defer payment of a Cash Award beyond the date that the Award would otherwise be payable, provided , that any such deferral shall be made in accordance with and subject to the applicable requirements of Section 409A, and that any amount so deferred shall be adjusted for notional interest or other notional earnings on a basis, determined by the Administrator, to the extent necessary to preserve the eligibility of the Award payment as exempt performance-based compensation under Section 162(m).

7. EFFECT OF CERTAIN TRANSACTIONS

(a) Mergers, Etc . Except as otherwise provided in an Award, the Administrator shall, in its sole discretion, determine the effect of a Covered Transaction on Awards, which determination may include, but is not limited to, the following actions:

(1) Assumption or Substitution . If the Covered Transaction is one in which there is an acquiring or surviving entity, the Administrator may provide for the assumption or continuation of some or all outstanding Awards or for the grant of new awards in substitution therefor by the acquiror or survivor or an affiliate of the acquiror or survivor.

(2) Cash-Out of Awards . If the Covered Transaction is one in which holders of Stock will receive upon consummation a payment (whether cash, non-cash or a combination of the foregoing), then subject to Section 7(a)(5) below the Administrator may provide for payment (a “cash-out”), with respect to some or all Awards or any portion thereof, equal in the case of each affected Equity Award or portion thereof to the excess, if any, of (A) the fair market value of one share of Stock times the number of shares of Stock subject to the Award or such portion, over (B) the aggregate exercise or purchase price, if any, under the Award or such portion (in the case of an SAR, the aggregate base value above which appreciation is measured), in each case on such payment terms (which need not be the same as the terms of payment to holders of Stock) and other terms, and subject to such conditions, as the Administrator determines; provided , that the Administrator shall not exercise its discretion under this Section 7(a)(2) with respect to an Award or portion thereof providing for “nonqualified deferred compensation” subject to Section 409A in a manner that would constitute an extension or acceleration of, or other change in, payment terms if such change would be inconsistent with the applicable requirements of Section 409A.

(3) Acceleration of Certain Awards . If the Covered Transaction (whether or not there is an acquiring or surviving entity) is one in which there is no assumption, continuation, substitution or cash-out, then subject to Section 7(a)(5) below, the Administrator may provide that each Equity Award requiring exercise will become fully exercisable, and the delivery of any shares of Stock remaining deliverable under each outstanding Award of Stock Units (including Restricted Stock Units and Performance Awards to the extent consisting of Stock Units) will be accelerated and such shares will be delivered, prior to the Covered Transaction, in each case on a basis that gives the holder of the Award a reasonable opportunity, as determined by the Administrator, following exercise of the Award or the delivery of the shares, as the case may be, to participate as a stockholder in the Covered Transaction; provided , that to the extent acceleration pursuant to this Section 7(a)(3) of an Award subject to Section 409A would cause the Award to fail to satisfy the requirements of Section 409A, the Award shall not be accelerated and the Administrator in lieu thereof shall take such steps as are necessary to ensure that payment of the Award is made in a medium

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other than Stock and on terms that as nearly as possible, but taking into account adjustments required or permitted by this Section 7, replicate the prior terms of the Award.

(4) Termination of Awards Upon Consummation of Covered Transaction . Each Award will terminate upon consummation of the Covered Transaction, other than the following: (i) Awards assumed pursuant to Section 7(a)(1) above; (ii) Awards converted pursuant to the proviso in Section 7(a)(3) above into an ongoing right to receive payment other than Stock; (iii) outstanding shares of Restricted Stock (which shall be treated in the same manner as other shares of Stock, subject to Section 7(a)(5) below); and (iv) Cash Awards that by their terms, or as a result of action taken by the Administrator, continue following such Covered Transaction.

(5) Additional Limitations . Any share of Stock and any cash or other property delivered pursuant to Section 7(a)(2) or Section 7(a)(3) above with respect to an Equity Award may, in the discretion of the Administrator, contain such restrictions, if any, as the Administrator deems appropriate to reflect any performance or other vesting conditions to which the Award was subject and that did not lapse (and were not satisfied) in connection with the Covered Transaction. For purposes of the immediately preceding sentence, a cash out under Section 7(a)(2) above or the acceleration of exercisability of an Award under Section 7(a)(3) above shall not, in and of itself, be treated as the lapsing (or satisfaction) of a performance or other vesting condition. In the case of Restricted Stock that does not vest in connection with the Covered Transaction, the Administrator may require that any amounts delivered, exchanged or otherwise paid in respect of such Stock in connection with the Covered Transaction be placed in escrow or otherwise made subject to such restrictions as the Administrator deems appropriate to carry out the intent of the Plan.

(b) Changes in and Distributions With Respect to Stock

(1) Basic Adjustment Provisions . In the event of a stock dividend, stock split or combination of shares (including a reverse stock split), recapitalization or other change in the Company’s capital structure that constitutes an equity restructuring within the meaning of FASB ASC Topic 718, the Administrator shall make appropriate adjustments to the maximum number of shares specified in Section 4(a) that may be delivered under the Plan and to the maximum share limits described in Section 4(c), and shall also make appropriate adjustments to the number and kind of shares of stock or securities subject to Equity Awards then outstanding or subsequently granted, any exercise prices relating to Equity Awards and any other provision of Awards affected by such change.

(2) Certain Other Adjustments . The Administrator may also make adjustments of the type described in Section 7(b)(1) above to take into account distributions to stockholders other than those provided for in Section 7(a) and 7(b)(1), or any other event, if the Administrator determines that adjustments are appropriate to avoid distortion in the operation of the Plan and to preserve the value of Awards made hereunder, having due regard for the qualification of ISOs under Section 422, the requirements of Section 409A, and the performance-based compensation rules of Section 162(m), to the extent applicable.

(3) Continuing Application of Plan Terms . References in the Plan to shares of Stock will be construed to include any stock or securities resulting from an adjustment pursuant to this Section 7.

8. LEGAL CONDITIONS ON DELIVERY OF STOCK

The Company will not be obligated to deliver any shares of Stock pursuant to the Plan or to remove any restriction from shares of Stock previously delivered under the Plan until: (i) the Company is satisfied that all legal matters in connection with the issuance and delivery of such shares have been addressed and resolved; (ii) if the outstanding Stock is at the time of delivery listed on any stock exchange or national market system, the shares to be delivered have been listed or authorized to be listed on such exchange or system upon official notice of issuance; and (iii) all conditions of the Award have been satisfied or waived. The Company may require, as a condition to exercise of the Award or delivery of shares of Stock under an Award, such representations or agreements as counsel for the Company may consider appropriate to avoid violation of such the Securities Act of

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1933, as amended, or any applicable state or non-U.S. securities law. Any Stock required to be issued to Participants under the Plan will be evidenced in such manner as the Administrator may deem appropriate, including book-entry registration or delivery of stock certificates. In the event that the Administrator determines that stock certificates will be issued to Participants under the Plan, the Administrator may require that certificates evidencing Stock issued under the Plan bear an appropriate legend reflecting any restriction on transfer applicable to such Stock, and the Company may hold the certificates pending lapse of the applicable restrictions.

9. AMENDMENT AND TERMINATION

The Administrator may at any time or times amend the Plan or any outstanding Award for any purpose which may at the time be permitted by law, and may at any time terminate the Plan as to any future grants of Awards; provided , that except as otherwise expressly provided in the Plan the Administrator may not, without the Participant’s consent, alter the terms of an Award so as to affect materially and adversely the Participant’s rights under the Award, unless the Administrator expressly reserved the right to do so at the time of the Award. Any amendments to the Plan shall be conditioned upon stockholder approval only to the extent, if any, such approval is required by law (including the Code and applicable stock exchange requirements), as determined by the Administrator. For the avoidance of doubt, no amendment to the Plan shall be effective unless approved by stockholders, to the extent stockholder approval is required under the rules of the applicable stock exchange on which the Stock is admitted to trading, if it would reduce the exercise price of any Stock Option previously granted hereunder or otherwise constitute a repricing and, without the receipt of such approval (to the extent so required), the Administrator shall not approve a repurchase by the Company for cash or other property of Stock Options or SARs for which the exercise price or base price, as applicable, exceeds the fair market value of a share of Stock as of the date of such repurchase.

10. OTHER COMPENSATION ARRANGEMENTS

The existence of the Plan or the grant of any Award will not in any way affect the Company’s right to award a person bonuses or other compensation in addition to Awards under the Plan.

11. MISCELLANEOUS

(a) Waiver of Jury Trial . By accepting an Award under the Plan, each Participant waives any right to a trial by jury in any action, proceeding or counterclaim concerning any rights under the Plan and any Award, or under any amendment, waiver, consent, instrument, document or other agreement delivered or which in the future may be delivered in connection therewith, and agrees that any such action, proceedings or counterclaim shall be tried before a court and not before a jury. By accepting an Award under the Plan, each Participant certifies that no officer, representative, or attorney of the Company has represented, expressly or otherwise, that the Company would not, in the event of any action, proceeding or counterclaim, seek to enforce the foregoing waivers.

(b) Limitation of Liability . Notwithstanding anything to the contrary in the Plan, neither the Company, nor any Affiliate, nor the Administrator, nor any person acting on behalf of the Company, any Affiliate, or the Administrator, shall be liable to any Participant or to the estate or beneficiary of any Participant or to any other holder of an Award by reason of any acceleration of income, or any additional tax (including any interest and penalties), asserted by reason of the failure of an Award to satisfy the requirements of Section 422 or Section 409A or by reason of Section 4999 of the Code, or otherwise asserted with respect to the Award; provided , that nothing in this Section 11(b) shall limit the ability of the Administrator or the Company, in its discretion, to provide by separate express written agreement with a Participant for a gross-up payment or other payment in connection with any such acceleration of income or additional tax.

12. ESTABLISHMENT OF SUB-PLANS

The Board may from time to time establish one or more sub-plans under the Plan for purposes of satisfying applicable blue sky, securities or tax laws of various jurisdictions. The Board will establish such sub-plans by

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adopting supplements to the Plan setting forth (i) such limitations on the Administrator’s discretion under the Plan as the Board deems necessary or desirable and (ii) such additional terms and conditions not otherwise inconsistent with the Plan as the Board deems necessary or desirable. All supplements adopted by the Board will be deemed to be part of the Plan, but each supplement will apply only to Participants within the affected jurisdiction and the Company will not be required to provide copies of any supplement to Participants in any jurisdiction that is not affected.

13. GOVERNING LAW

Except as otherwise provided by the express terms of an Award agreement or under a sub-plan described in Section 12, the provisions of the Plan and of Awards under the Plan and all claims or disputes arising out of our based upon the Plan or any Award under the Plan or relating to the subject matter hereof or thereof will be governed by and construed in accordance with the General Corporation Law of the State of Delaware as to matters within the scope thereof, and as to all other matters shall be governed by and construed in accordance with the domestic substantive laws of the State of Delaware without giving effect to any choice or conflict of laws provision or rule that would cause the application of the domestic substantive laws of any other jurisdiction.

EXHIBIT A

Definition of Terms

The following terms, when used in the Plan, will have the meanings and be subject to the provisions set forth below:

“Administrator”:  The Compensation Committee, except that the Compensation Committee may delegate (i) to one or more of its members (or one or more other members of the Board, including the full Board) such of its duties, powers and responsibilities as it may determine; (ii) to one or more officers of the Company the power to grant Awards to the extent permitted by Section 157(c) of the Delaware General Corporation Law; and (iii) to such Employees or other persons as it determines such ministerial tasks as it deems appropriate.

“Affiliate” : Any corporation or other entity that stands in a relationship to the Company that would result in the Company and such corporation or other entity being treated as one employer under Section 414(b) and Section 414(c) of the Code, except that in determining eligibility for the grant of a Stock Option or SAR by reason of service for an Affiliate, Sections 414(b) and 414(c) of the Code shall be applied by substituting “at least 50%” for “at least 80%” under Section 1563(a)(1), (2) and (3) of the Code and Treas. Regs. § 1.414(c)-2; provided , that to the extent permitted under Section 409A, “at least 20%” shall be used in lieu of “at least 50%”; and further provided , that the lower ownership threshold described in this definition (50% or 20% as the case may be) shall apply only if the same definition of affiliation is used consistently with respect to all compensatory stock options or stock awards (whether under the Plan or another plan). The Company may at any time by amendment provide that different ownership thresholds (consistent with Section 409A) apply but any such change shall not be effective for twelve (12) months.

“Award”:  Any or a combination of the following:

(i) Stock Options.

(ii) SARs.

(iii) Restricted Stock.

(iv) Unrestricted Stock.

(v) Stock Units, including Restricted Stock Units.

(vi) Performance Awards.

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(vii) Cash Awards.

(viii) Awards (other than Awards described in (i) through (vii) above) that are convertible into or otherwise based on Stock.

“Board”:  The Board of Directors of the Company; provided , however, that if the Company is a direct or indirect subsidiary of a publicly held corporation, it shall mean the Board of Directors of the publicly held corporation.

“Cash Award”:  An Award denominated in cash.

“Code”:  The U.S. Internal Revenue Code of 1986 as from time to time amended and in effect, or any successor statute as from time to time in effect.

“Compensation Committee”:  In the event that the Company is a direct or indirect subsidiary of a publicly held corporation, the Compensation Committee shall mean the Compensation Committee of the Board of the publicly held corporation; otherwise, Compensation Committee shall mean the Compensation Committee of the Board.

“Company”:  RXi Pharmaceuticals Corporation.

“Covered Transaction”:   Any of (i) a consolidation, merger, or similar transaction or series of related transactions, including a sale or other disposition of stock, in which the Company is not the surviving corporation or which results in the acquisition of all or substantially all of the Company’s then outstanding common stock by a single person or entity or by a group of persons and/or entities acting in concert, (ii) a sale or transfer of all or substantially all the Company’s assets, or (iii) a dissolution or liquidation of the Company. Where a Covered Transaction involves a tender offer that is reasonably expected to be followed by a merger described in clause (i) (as determined by the Administrator), the Covered Transaction shall be deemed to have occurred upon consummation of the tender offer.

“Employee”:  Any person who is employed by the Company or an Affiliate.

“Employment”:   A Participant’s employment or other service relationship with the Company and its Affiliates. Employment will be deemed to continue, unless the Administrator expressly provides otherwise, so long as the Participant is employed by, or otherwise is providing services in a capacity described in Section 5 to the Company or its Affiliates. If a Participant’s employment or other service relationship is with an Affiliate and that entity ceases to be an Affiliate, the Participant’s Employment will be deemed to have terminated when the entity ceases to be an Affiliate unless the Participant transfers Employment to the Company or its remaining Affiliates. Notwithstanding the foregoing and the definition of “Affiliate” above, in construing the provisions of any Award relating to the payment of “nonqualified deferred compensation” (subject to Section 409A) upon a termination or cessation of Employment, references to termination or cessation of employment, separation from service, retirement or similar or correlative terms shall be construed to require a “separation from service” (as that term is defined in Section 1.409A-1(h) of the Treasury Regulations) from the Company and from all other corporations and trades or businesses, if any, that would be treated as a single “service recipient” with the Company under Section 1.409A-1(h)(3) of the Treasury Regulations. The Company may, but need not, elect in writing, subject to the applicable limitations under Section 409A, any of the special elective rules prescribed in Section 1.409A-1(h) of the Treasury Regulations for purposes of determining whether a “separation from service” has occurred. Any such written election shall be deemed a part of the Plan.

“Equity Award” : Awards other than Cash Awards.

“ISO”:  A Stock Option intended to be an “incentive stock option” within the meaning of Section 422. Each option granted pursuant to the Plan will be treated as providing by its terms that it is to be a non-incentive stock option unless, as of the date of grant, it is expressly designated as an ISO.

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“Participant”:  A person who is granted an Award under the Plan.

“Performance Award” : An Award subject to Performance Criteria. The Committee in its discretion may grant Performance Awards that are intended to qualify as exempt performance-based compensation under Section 162(m) and Performance Awards that are not intended so to qualify.

“Performance Criteria” : For a Performance Period, specified criteria, other than the mere continuation of Employment or the mere passage of time, the satisfaction of which is a condition for the grant, exercisability, vesting or full enjoyment of an Award. For purposes of Awards that are intended to qualify for the performance-based compensation exception under Section 162(m), a Performance Criterion will mean an objectively determinable measure of performance relating to any or any combination of the following (measured either absolutely or by reference to an index or indices and determined either on a consolidated basis or, as the context permits, on a divisional, subsidiary, line of business, project or geographical basis or in combinations thereof): sales; revenues; assets; expenses; earnings before or after deduction for all or any portion of interest, taxes, depreciation, or amortization, whether or not on a continuing operations or an aggregate or per share basis; return on equity, investment, capital or assets; one or more operating ratios; borrowing levels, leverage ratios or credit rating; market share; capital expenditures; cash flow; stock price; stockholder return; sales of particular products or services; customer acquisition or retention; acquisitions and divestitures (in whole or in part); joint ventures and strategic alliances; spin-offs, split-ups and the like; reorganizations; or recapitalizations, restructurings, financings (issuance of debt or equity) or refinancings. A Performance Criterion and any targets with respect thereto determined by the Administrator need not be based upon an increase, a positive or improved result or avoidance of loss. To the extent consistent with the requirements for satisfying the performance-based compensation exception under Section 162(m), the Administrator may establish that in the case of any Award intended to qualify for such exception that one or more of the Performance Criteria applicable to such Award will be adjusted in an objectively determinable manner to reflect events (for example, the impact of charges for restructurings, discontinued operations, mergers, acquisitions, extraordinary items, and other unusual or non-recurring items, and the cumulative effects of tax or accounting changes, each as defined by U.S. generally accepted accounting principles) occurring during the Performance Period that affect the applicable Performance Criterion or Criteria.

“Plan”:  The RXi Pharmaceuticals Corporation 2012 Long Term Incentive Plan as from time to time amended and in effect.

“Restricted Stock”:  Stock subject to restrictions requiring that it be redelivered or offered for sale to the Company if specified conditions are not satisfied.

“Restricted Stock Unit”:  A Stock Unit that is, or as to which the delivery of Stock or cash in lieu of Stock is, subject to the satisfaction of specified performance or other vesting conditions.

“SAR”: A right entitling the holder upon exercise to receive an amount (payable in cash or in shares of Stock of equivalent value) equal to the excess of the fair market value (as defined in Section 6(b)) of the shares of Stock subject to the right over the base value from which appreciation under the SAR is to be measured.

“Section 409A”:  Section 409A of the Code.

“Section 422”:  Section 422 of the Code.

“Section 162(m)”:  Section 162(m) of the Code.

“Stock”:  Common stock of the Company, par value $0.0001 per share.

“Stock Option”:  An option entitling the holder to acquire shares of Stock upon payment of the exercise price.

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“Stock Unit” : An unfunded and unsecured promise, denominated in shares of Stock, to deliver Stock or cash measured by the value of Stock in the future.

Substitute Awards ”: Awards that are the result of converting, replacing, or adjusting equity awards of an acquired company in connection with the acquisition.

“Unrestricted Stock”: Stock not subject to any restrictions under the terms of the Award .

First Amendment to RXi Pharmaceuticals Corporation 2012 Long Term Incentive Plan

(Adopted June 7, 2013)

The reference in Section 4(a) of the RXi Pharmaceuticals Corporation 2012 Incentive Plan (the “Plan”) to the maximum number of shares of “Stock” (as defined) that may be delivered in satisfaction of “Awards” (as defined) under the Plan shall be 500,000 shares. All related Plan information shall also be amended accordingly.

Proposed Second Amendment to RXi Pharmaceuticals Corporation 2012 Long Term Incentive Plan

Section 4(a) of the RXi Pharmaceuticals Corporation 2012 Long Term Incentive Plan is hereby amended and restated as follows and all related Plan information shall be amended accordingly:

(a) Number of Shares . The maximum number of shares of Stock that may be delivered upon satisfaction of Equity Awards under the Plan shall be 1,250,000 shares of Stock. Up to the total number of shares of Stock set forth in the preceding sentence may be issued in satisfaction of ISOs, but nothing in this Section 4(a) shall be construed as requiring that any, or any fixed number of, ISOs be awarded under the Plan. The number of shares of Stock delivered in satisfaction of Equity Awards shall, for purposes of this Section 4(a), be determined net of shares of Stock withheld by the Company in payment of the exercise price of the Award or in satisfaction of tax withholding requirements with respect to the Award and, for the avoidance of doubt, without including any shares of Stock underlying Awards settled in cash or which otherwise expire or become unexercisable without having been exercised or are forfeited to or repurchased by the Company due to failure to vest. The limits set forth in this Section 4(a) shall be construed to comply with Section 422. To the extent consistent with the requirements of Section 422 and with other applicable legal requirements (including applicable stock exchange requirements, if any), Stock issued under Substitute Awards shall not reduce the number of shares available for Awards under the Plan. The shares which may be delivered under Substitute Awards shall be in addition to the limitations set forth in this Section 4(a) on the number of shares available for issuance under the Plan, and such Substitute Awards shall not be subject to the per Participant Award limits described in Section 4(c) below.

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Electronic Voting Instructions

Available 24 hours a day, 7 days a week!

Instead of mailing your proxy, you may choose one of the voting methods outlined below to vote your proxy.

VALIDATION DETAILS ARE LOCATED BELOW IN THE TITLE BAR.

Proxies submitted by the Internet or telephone must be received by 11:59 p.m., Eastern Time, on December 14, 2016.

 

		Vote by Internet   • Go to www.envisionreports.com/RXII   • Or scan the QR code with your smartphone   • Follow the steps outlined on the secure website

Vote by telephone

 

•

Call toll free 1-800-652-VOTE (8683) within the USA, US territories & Canada on a touch tone telephone

 

•

Follow the instructions provided by the recorded message

q IF YOU HAVE NOT VOTED VIA THE INTERNET OR TELEPHONE, FOLD ALONG THE PERFORATION, DETACH AND RETURN THE BOTTOM PORTION IN THE ENCLOSED ENVELOPE. q

Please sign exactly as your name(s) appear(s) hereon. When signing as attorney, executor, administrator, or other fiduciary, please give full title as such. Joint owners should each sign personally. All holders must sign. If a corporation or partnership, please sign in full corporate or partnership name, by authorized officer.

q IF YOU HAVE NOT VOTED VIA THE INTERNET OR TELEPHONE, FOLD ALONG THE PERFORATION, DETACH AND RETURN THE BOTTOM PORTION IN THE ENCLOSED ENVELOPE. q

Proxy — RXi PHARMACEUTICALS CORPORATION

Annual Meeting of Stockholders

December 15, 2016 10:00 a.m.

This proxy is solicited by the Board of Directors

The stockholder(s) hereby appoint Geert Cauwenbergh as proxy with the power to appoint his substitute, and hereby authorize him to represent and to vote, as designated on the reverse side of this ballot, all of the shares of Common Stock of RXi Pharmaceuticals Corporation that the stockholder(s) is/are entitled to vote at the 2016 Annual Meeting of Stockholders to be held on December 15, 2016 at 200 Park Avenue, New York, New York 10166 10:00 a.m. local time, and at any adjournment or postponement thereof.

This proxy, when properly executed, will be voted in the manner directed herein. If no such direction is made, this proxy will be voted in accordance with the Board of Directors’ recommendations and in the discretion of the proxy holders on all other matters that may come before the meeting.

Continued and to be signed on reverse side