CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
We consent to the inclusion in this Pre-Effective Amendment No. 2 to the Registration Statement of Onconova Therapeutics, Inc. on Form S-1 (No. 333-189358) to be filed on or about July 17, 2013 of our report dated May 2, 2013, except for the third paragraph of Note 18, as to which the date is July 17, 2013, on our audit of the financial statements as of December 31, 2011 and for year ended December 31, 2011. We also consent to the reference to our firm under the caption "Experts" in the Registration Statement on Form S-1.
/s/ EISNERAMPER LLP
Iselin, New Jersey
July 17, 2013
