Exhibit 3.1

CERTIFICATE OF AMENDMENT TO THE

AMENDED AND RESTATED CERTIFICATE OF INCORPORATION

OF

TELIK, INC.

TELIK, INC., a corporation organized and existing under the General Corporation law of the State of Delaware (the “Corporation”) does hereby certify:

ONE: The original name of this Company is Terrapin Diagnostics, Inc. and the date of filing of its original Certificate of Incorporation with the Secretary of State of the State of Delaware was on October 20, 1988.

TWO: The Board of Directors of the Corporation, acting in accordance with the provision of Sections 141 and 242 of the General Corporation Law of the State of Delaware adopted resolutions to amend Paragraph A of Article IV of the Amended and Restated Certificate of Incorporation of the Corporation to read in its entirety as follows:

“This corporation is authorized to issue two classes of stock to be designated, respectively, “Common Stock” and “Preferred Stock.” The total number of shares which the corporation is authorized to issue is one hundred five million (105,000,000) shares. One hundred million (100,000,000) shares shall be Common Stock, each having a par value of one cent ($0.01). Five million (5,000,000) shares shall be Preferred Stock, each having a par value of one cent ($0.01). Effective as of 11:00 a.m., Eastern time, on the date this Certificate of Amendment to the Amended and Restated Certificate of Incorporation is filed with the Secretary of State of the State of Delaware, each thirty (30) shares of the Corporation’s Common Stock, par value $0.01 per share, issued and outstanding shall, automatically and without any action on the part of the respective holders thereof, be combined and converted into one (1) share of Common Stock, par value $0.01 per share, of the Corporation. No fractional shares shall be issued and, in lieu thereof, any holder of less than one share of Common Stock will be entitled to receive cash for such holder’s fractional share based upon the closing sales price of the Corporation’s Common Stock as reported on the NASDAQ Capital Market as of the date this Certificate of Amendment is filed with the Secretary of State of the State of Delaware.”

THREE: Thereafter, pursuant to a resolution by the Board of Directors of the Corporation, this Certificate of Amendment was submitted to the stockholders of the corporation for their consideration and was duly adopted and approved in accordance with the provisions of Sections 228 and 242 of the General Corporation Law of the State of Delaware at a annual meeting of the stockholders.

IN WITNESS WHEREOF, Telik, Inc. has caused this CERTIFICATE OF AMENDMENT TO THE AMENDED AND RESTATED CERTIFICATE OF INCORPORATION to be signed by its Chief Executive Officer this 28^th day of March, 2012.