Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
ROSENWALD LINDSAY A MD
   2. Issuer Name and Ticker or Trading Symbol
ZIOPHARM ONCOLOGY INC [ZIOP] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
787 SEVENTH AVENUE, 48TH FLOOR		 3. Date of Earliest Transaction (Month/Day/Year)
05/03/2006
(Street)

NEW YORK, NY 10019		 4. If Amendment, Date 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
(City)
(State)
(Zip)
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               476,678 D  

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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 Underlying Securities
(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 of Derivative Security: 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
Warrants $ 4.75             05/31/2005 05/31/2012 Common Stock 221,011   221,011 D  
Warrants $ 4.75             12/23/2004 12/23/2011 Common Stock 62,621   62,621 I Owned by Paramount Biocapital Investments, LLC (1)
Common Stock $ 0.01             02/13/2006   (3) Common Stock 563,296   563,296 I Owned by individuals and pledged to Lindsay A. Rosenwald, M.D. to secure certain obligations (2)
Warrants $ 5.09 05/03/2006   J(4)   250,188   05/03/2006 05/03/2013 Common Stock 250,188 $ 0 250,188 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
ROSENWALD LINDSAY A MD
787 SEVENTH AVENUE
48TH FLOOR
NEW YORK, NY 10019		     X    

Signatures

 /s/ Lindsay A. Rosenwald, M.D.   05/05/2006
**Signature of Reporting Person Date

Explanation of Responses:

* 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).
(1) These Warrants are held by Paramount Biocapital Investments, LLC, of which Dr. Rosenwald is managing member. Dr. Rosenwald disclaims beneficial ownership of these Warrants, except to the extent of his pecuniary interest therein, if any.
(2) These Shares are held by certain individuals and with respect to which Dr. Rosenwald has certain call rights pursuant to pledge agreements to secure certain obligations. Dr. Rosenwald disclaims beneficial ownership of these 563,296 pledged Shares, except to the extent of his pecuniary interest therein, if any.
(3) These call rights expire upon satisfaction of certain obligations of Dr. Rosenwald to a third party and may be extended indefinitely, although such obligations are currently contemplated to be satisfied (or not satisfied) by December 31, 2007.
(4) Paramount BioCapital, Inc. ("Paramount"), an NASD member broker dealer, acted as co-placement agent for the Issuer in a private placement of the Issuer's securities consummated on May 3, 2006. In connection with such activities, Paramount has designated to Dr. Rosenwald, among other compensation, warrants to purchase 250,188 shares of common stock, par value $.001 per share, of the Issuer. Dr. Rosenwald is chairman, Chief Executive Officer and sole stockholder of Paramount.

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