DEFA14A

The Board of Directors recommends that you vote FOR the following:

To elect five members to the Board
of Directors to hold office until
the 2019 annual meeting of
stockholders and until their
successors are duly elected and
qualified.

Nominees

01 DAVID J. CHAPLIN 02 SIMON C. PEDDER 03 DONALD R. REYNOLDS 04 BOBBY W. SANDAGE, JR. 05 WILLIAM D. SCHWIETERMAN

To approve the amended and restated Mateon Therapeutics, Inc. 2015 Equity Incentive Plan, which includes an increase in the number of shares available for the grant of awards from 4,725,781 to 7,250,000 shares.

To approve an amendment to the Company’s Restated Certificate of Incorporation, as amended, to increase the number of authorized shares of common stock from 70,000,000 to 150,000,000.

LOGO

To ratify the appointment of OUM & CO. LLP as the Company’s independent registered public accounting firm for the fiscal year ending December 31, 2018.

NOTE: If any other matters properly come before the annual meeting, or any adjournments thereof, the persons named in this proxy will vote on such matters in their discretion.

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						Proxy Materials Available to VIEW or RECEIVE:
						1. Notice & Proxy Statement 2. Form 10-K How to View Online: Have the information that is printed in the box marked by the arrow (located on the following page) and visit: www.proxyvote.com. How to Request and Receive a PAPER or E-MAIL Copy: If you want to receive a paper or e-mail copy of these documents, you must request one. There is NO charge for requesting a copy. Please choose one of the following methods to make your request: 1) BY INTERNET: www.proxyvote.com 2) BY TELEPHONE: 1-800-579-1639 3) BY E-MAIL: sendmaterial@proxyvote.com If requesting materials by e-mail, please send a blank e-mail with the information that is printed in the box marked by the arrow (located on the following page) in the subject line. Requests, instructions and other inquiries sent to this e-mail address will NOT be forwarded to your investment advisor. Please make the request as instructed above on or before June 06, 2018 to facilitate timely delivery.



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