Washington, D.C. 20549


Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940
OMB Number: 3235-0287
Estimated average burden
hours per response: 0.5
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
1. Name and Address of Reporting Person*

(Last) (First) (Middle)
SUITE 1104


(City) (State) (Zip)
2. Issuer Name and Ticker or Trading Symbol
Onconova Therapeutics, Inc. [ ONTX ]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
Director X 10% Owner
Officer (give title below) Other (specify below)
3. Date of Earliest Transaction (Month/Day/Year)
4. If Amendment, Date of Original Filed (Month/Day/Year)
6. Individual or Joint/Group Filing (Check Applicable Line)
X Form filed by One Reporting Person
Form filed by More than One Reporting Person
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 02/08/2018 P 1,100,000 A $1.01 2,097,022 I See Note(1)
Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3) 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code (Instr. 8) 5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 6. Date Exercisable and Expiration Date (Month/Day/Year) 7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4) 8. Price of Derivative Security (Instr. 5) 9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4) 10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 11. Nature of Indirect Beneficial Ownership (Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Series A Convertible Preferred Stock Purchase Warrant $1.01(2) 02/08/2018 P 1,100,000 02/08/2018 (3) Series A Preferred Stock 110,000(2)(3) $0(2)(4) 1,100,000 I See Note(1)
Explanation of Responses:
1. Tyndall Capital Partners, L.P. ("Tyndall Capital") is the general partner of Tyndall Partners, L.P. ("Tyndall"), and possesses the sole power to vote and the sole power to direct the disposition of all securities held by Tyndall. Tyndall Capital's interest in the securities reported herein is limited to the extent of its pecuniary interest in such securities, if any.
2. Each warrant ("Warrant") is exercisable into 0.1 share of Series A Convertible Preferred Stock, par value $0.01 per share ("Preferred Stock") at an exercise price of $1.01 per 0.1 share of Preferred Stock. Each 0.1 share of Preferred Stock will be convertible into one share of common stock, par value $0.01 per share (the "Common Stock"). The Company does not currently have a sufficient number of authorized shares of Common Stock to cover the shares issuable upon the conversion of Series A Preferred Stock. As a result, before any shares of Preferred Stock can be converted, the Issuer must obtain stockholder approval of an amendment (the "Charter Amendment") to its Tenth Amended and Restated Certificate of Incorporation, as amended, to sufficiently increase its authorized shares of Common Stock to cover the conversion of all outstanding shares of Preferred Stock into Common Stock.
3. The Warrants are exercisable immediately and will expire on the later of (i) the one-year anniversary of the date (the "Charter Amendment Date") on which Issuer publicly announces through the filing of a Current Report on Form 8-K that the amendment to their certificate of incorporation to sufficiently increase their authorized shares of Common Stock to cover the conversion of all outstanding shares of Series A Preferred Stock into Common Stock has been filed with the Secretary of State of the State of Delaware and (ii) the earlier of (A) the one-month anniversary of the date on which Issuer publicly releases their top-line results of the INSPIRE Pivotal phase 3 that compare the overall survival (OS) of patients in the rigosertib group vs the Physician's Choice group, in all patients and in a subgroup of patients with IPSS-R very high risk and (B) December 31, 2019.
4. 1,100,000 Units purchased for $1.01 per Unit. Each Unit consists of one share of Common Stock and one Warrant.
/s/ Jeffery S. Halis, Manager of Jeffrey Management, LLC, General Partner of Tyndall Capital Partners, L.P. 02/12/2018
** Signature of Reporting Person Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
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