Attached files

file filename
EX-10.33 - EX-10.33 - Oncotelic Therapeutics, Inc.d387311dex1033.htm
EX-10.32 - EX-10.32 - Oncotelic Therapeutics, Inc.d387311dex1032.htm
EX-5.1 - EX-5.1 - Oncotelic Therapeutics, Inc.d387311dex51.htm
EX-4.12 - EX-4.12 - Oncotelic Therapeutics, Inc.d387311dex412.htm
EX-4.11 - EX-4.11 - Oncotelic Therapeutics, Inc.d387311dex411.htm
EX-4.10 - EX-4.10 - Oncotelic Therapeutics, Inc.d387311dex410.htm
S-1/A - S-1/A - Oncotelic Therapeutics, Inc.d387311ds1a.htm

Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We hereby consent to the incorporation by reference, in the Prospectus constituting a part of this Amendment No. 1 to the Registration Statement on Form S-1 (No. 333-217904), of our report dated March 30, 2017 (which report expresses an unqualified opinion and includes an explanatory paragraph expressing substantial doubt about the Company’s ability to continue as a going concern), relating to the financial statements of Mateon Therapeutics, Inc. included in the Annual Report on Form 10-K for the year ended December 31, 2016.

We also consent to the reference to us under the caption “Experts” in the Prospectus.

/s/ OUM & CO. LLP

San Francisco, California

June 12, 2017