Traws Pharma, Inc. — Director's Dealing 2018

May 1, 2018

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: Onconova Therapeutics, Inc. (ONTX)
CIK: 0001130598
Period of Report: 2018-04-27

Reporting Person: 683 Capital Management, LLC (10% Owner)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2018-04-27	Common Stock, $0.01 par value	P	11838235	$0.425	Acquired	14503169	Indirect

Footnotes

F1: This Form 4 is filed jointly by 683 Capital Management, LLC ("683 Management"), 683 Capital Partners, LP ("683 Partners") and Ari Zweiman (collectively, the "Reporting Persons"). Each of the Reporting Persons may be deemed to be a member of a Section 13(d) group that collectively owns more than 10% of the Issuer's outstanding shares of Common Stock. Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein except to the extent of his or its pecuniary interest therein.

F2: Represents securities held directly by 683 Partners. 683 Management is the investment manager of 683 Partners. Ari Zweiman is the Managing Member of 683 Management. As a result, each of 683 Management and Ari Zweiman may be deemed to beneficially own the securities held by 683 Partners.