Unassociated Document


    Exhibit
10.1

     

    AMENDMENT
TO

    STOCK
PURCHASE AGREEMENT

     

    This
Amendment, dated as of February 1, 2011 (this “Amendment”), to the
Stock Purchase Agreement, dated as of January 6, 2011 (the “Purchase Agreement”),
by and between ZIOPHARM Oncology, Inc., a Delaware corporation (the “Company”), and
Intrexon Corporation, a Virginia corporation (“Intrexon”).  Capitalized
terms used in this Amendment and not otherwise defined shall have the respective
meanings ascribed to such terms in the Purchase Agreement.

     

    WHEREAS,
Section 10.2 of the Purchase Agreement permits the amendment of the
Purchase Agreement by execution of an instrument in writing signed by each of
the parties to be bound; and

     

    WHEREAS,
the Company and Intrexon desire to amend the Purchase Agreement as provided
herein.

     

    NOW,
THEREFORE, in consideration of the mutual agreements specified in this
Amendment, the parties hereby agree as follows:

     

    1. Amendment of
Section 7.1 of the Purchase Agreement.  Section 7.1 of
the Purchase Agreement is hereby amended to add subsection (c) as
follows:

     

    “7.1           Intrexon
Commitment.  ....

     

    (c)           In
the event that Intrexon voluntarily elects to purchase securities in a Qualified
Financing for which the Company does not request that Intrexon participate, as
contemplated by this Section 7.1, the aggregate purchase price paid by Intrexon
for such securities shall nonetheless be applied against and reduce the then
remaining maximum amount of Intrexon’s $50,000,000 commitment
hereunder.”

     

    2. Representations and
Warranties.  Each of the Company and Intrexon represents and
warrants that (i) it has the corporate power and authority to execute and
deliver this Amendment, (ii) this Amendment has been duly and validly
authorized by all necessary action of its board of directors, and
(iii) this Amendment has been duly and validly executed and delivered and,
assuming due authorization and execution by the other parties hereto,
constitutes its legal, valid and binding obligation enforceable against it in
accordance with its terms.

     

    3. No Other
Modification.  The Purchase Agreement shall not be modified by
this Amendment in any respect except as expressly set forth herein.

     

    4. Governing
Law.  This Amendment and the rights and obligations of the
parties hereto shall be governed by and construed in accordance with the laws of
the State of New York as applied to contracts entered into and performed
entirely in the State of New York by New York residents, without regard to
conflicts of law principles.

     

    5. Counterparts.  This
Amendment may be executed in two or more counterparts, each of which shall
constitute an original, but all of which, when taken together, shall constitute
but one instrument, and shall become effective when one or more counterparts
have been signed by each party hereto and delivered to the other
parties.

     

    
      
         

      

      
         

        
          

        

      

      
         

      

    

    


     

    IN
WITNESS WHEREOF, the parties hereto have caused this Amendment to be executed by
their duly authorized respective officers as of the date first written
above.

     

    


     

    
      
        	
                COMPANY:

                 

              	
                INTREXON:

                 

              
	
                ZIOPHARM
      ONCOLOGY, INC.

                 

                 

                 

                By:           /s/ Jonathan
      Lewis                                        

                Name:
      Jonathan Lewis, MD, PhD

                Title:
      Chief Executive Officer

              	
                INTREXON
      CORPORATION

                 

                 

                By:           /s/ Randal J.
      Kirk                                

                Name:
      Randal J. Kirk

                Title:
      Chief Executive Officer