Exhibit 3.3

AMENDED AND RESTATED

CERTIFICATE OF INCORPORATION

Reata Pharmaceuticals, Inc.

(a Delaware Corporation)

ARTICLE ONE

The name of the corporation (hereinafter called the “Corporation”) is Reata Pharmaceuticals, Inc.

ARTICLE TWO

The address, including street, number, city, and county, of the registered office of the Corporation in the State of Delaware is 3411 Silverside Road Rodney Building #104, Wilmington, 19810, County of New Castle, Delaware and the name of the registered agent of the Corporation in the State of Delaware at such address is Corporate Creations Network Inc.

ARTICLE THREE

The purpose of the Corporation is to engage in any lawful act or activity for which a corporation may now or hereafter be organized under the General Corporation Law of the State of Delaware (the “DGCL”).

ARTICLE FOUR

The aggregate number of shares which the Corporation shall have authority to issue is 1,000 shares of Common Stock, par value $0.001 per share.

ARTICLE FIVE

In furtherance and not in limitation of the powers conferred upon it by law, the Board of Directors of the Corporation is expressly authorized to adopt, amend or repeal the By-laws of the Corporation.

ARTICLE SIX

A director of this Corporation shall not be personally liable to the Corporation or its stockholders for monetary damages for breach of fiduciary duty as a director, except for liability (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. If the DGCL is amended to authorize the further elimination or limitation of the liability of directors, then the liability of a director of the Corporation, in addition to the limitation on personal liability provided in this Certificate, shall be eliminated or limited to the fullest extent permitted by the DGCL as so amended. No amendment to or repeal of this Article Eleven shall apply to or have any effect on the liability or alleged liability of any director of the Corporation for or with respect to any acts or omissions of such director occurring prior to such amendment or repeal.

ARTICLE SEVEN

The Corporation shall indemnify any person who was, is or is threatened to be made a party to a proceeding (as hereinafter defined) by reason of the fact that he or she (i) is or was a director or officer of the Corporation or (ii) while a director or officer of the Corporation, is or was serving at the request of the Corporation as a director, officer, partner, venturer, proprietor, trustee, employee, agent, or similar functionary of another foreign or domestic corporation, partnership, joint venture, sole proprietorship, trust, employee benefit plan, or other enterprise, to the fullest extent permitted under the DGCL, as the same exists or may hereafter be amended. Such right shall be a contract right and as such shall inure to the benefit of any director or officer who is elected and accepts the position of director or officer of the Corporation or elects to continue to serve as a director or officer of the Corporation while this Article Thirteen is in effect. Any repeal or amendment of this Article Thirteen shall be prospective only and shall not limit the rights of any such director or officer or the obligations of the Corporation with respect to any claim arising from or related to the services of such director or officer in any of the foregoing capacities prior to any such repeal or amendment to this Article Thirteen. Such right shall include the right to be paid by the Corporation expenses (including without limitation attorneys’ fees) actually and reasonably incurred by him in defending any such proceeding in advance of its final disposition to the maximum extent permitted under the DGCL, as the same exists or may hereafter be amended. If a claim for indemnification or advancement of expenses hereunder is not paid in full by the Corporation within sixty (60) days after a written claim has been received by the Corporation, the claimant may at any time thereafter bring suit against the Corporation to recover the unpaid amount of the claim, and if successful in whole or in part, the claimant shall also be entitled to be paid the expenses of prosecuting such claim. It shall be a defense to any such action that such indemnification or advancement of costs of defense is not permitted under the DGCL, but the burden of proving such defense shall be on the Corporation. Neither the failure of the Corporation (including its Board or any committee thereof, independent legal counsel, or stockholders) to have made its determination prior to the commencement of such action that indemnification of, or advancement of costs of defense to, the claimant is

permissible in the circumstances nor any actual determination by the Corporation (including its Board or any committee thereof, independent legal counsel, or stockholders) that such indemnification or advancement is not permissible shall be a defense to the action or create a presumption that such indemnification or advance is not permissible. In the event of the death of any person having a right of indemnification under the foregoing provisions, such right shall inure to the benefit of his or her heirs, executors, administrators, and personal representatives. The rights conferred above shall not be exclusive of any other right which any person may have or hereafter acquire under any statute, bylaw, resolution of stockholders or directors, agreement or otherwise.

ARTICLE EIGHT

Unless and except to the extent that the By-laws of the Corporation shall so require, the election of directors of the Corporation need not be by written ballot.

REATA PHARMACEUTICALS INC 8-K