Exhibit 10.25


 


AMENDMENT
NO. 1 TO


SECURITIES
PURCHASE AGREEMENT


 


This Amendment No. 1 (the
“Amendment”) is entered into as of December 13, 2012, by and between Arno Therapeutics, Inc., a Delaware
corporation (the “Company”), and the undersigned Purchasers.


 


WHEREAS, the Company and
the undersigned Purchasers are, together with certain other Purchasers, parties to that certain Securities Purchase Agreement dated
November 26, 2012 (the “Purchase Agreement”);


 


WHEREAS, Section 5.5 of
the Purchase Agreement provides that the provisions of the Purchase Agreement may only be waived, modified, supplemented or amended
by a written instrument signed by the Company and the Purchasers holding at least two-thirds of the Securities then outstanding;


 


WHEREAS, the undersigned
Purchasers collectively hold more than two-thirds of the Securities outstanding; and


 


WHEREAS, in accordance
with Section 5.5 of the Purchase Agreement, the Company and the undersigned Purchasers desire to (i) extend the deadline for completing
the Subsequent Closing, and (ii) expand the list of Additional Purchasers that may participate in the Subsequent Closing.


 


NOW, THEREFORE, in consideration
of the mutual covenants and agreements contained herein, the parties hereby agree as follows:


 


1.          Subsequent
Closings. Section 2.1(b) of the Purchase Agreement is hereby amended and restated in its entirety as follows:


 


“(b)    Subsequent
Closings. Following the Initial Closing Date and until December 18, 2012, the Company may sell, on the same terms and conditions
as those contained in this Agreement, an additional principal amount of Debentures equal to the Maximum Amount less the amount
sold to Purchasers in the Initial Closing, to one or more Purchasers, ROFR Purchasers and/or a new purchaser described from the
list set forth on Schedule 2.1(b) (each such ROFR Purchaser or other new purchaser, an “Additional Purchaser”);
provided, however, that each Purchaser participating in the Initial Closing shall have the right to purchase up to
its pro-rata share (based on the amounts of Debentures and Warrants that such Purchaser purchased at the Initial Closing) of the
portion of such Subsequent Closing not subscribed to by a ROFR Purchaser. Each Additional Purchaser that subscribes to the Subsequent
Closing shall be required to become a party to this Agreement and the Registration Rights Agreement by executing and delivering
a counterpart signature page thereto, and shall otherwise be deemed a “Purchaser” for purposes of this Agreement. The
Company shall provide Purchasers with at least 2 Trading Days’ notice (but not to exceed 4 Trading Days prior to the Subsequent
Closing) of the occurrence of the Subsequent Closing and, if a Purchaser wants to participate, it will provide the Company with
at least one Trading Day notice of such participation. There shall only be one Subsequent Closing.


 



    	 



    	 



    

 


2.          Amendment
and Restatement of Schedule 2.1(b). Schedule 2.1(b) is hereby amended and restated in its entirety as set forth on Exhibit
A hereto.


 


3.          Miscellaneous.
All capitalized terms used but not defined herein shall have the meanings ascribed to them in the Purchase Agreement. Except as
amended or modified by this Amendment, the parties hereby confirm all other terms and provisions of the Purchase Agreement. This
Amendment may be executed in any number of counterparts, each of which shall constitute an original, but all of which together
shall constitute one and the same instrument.


 


Signature Pages Follow


 



    	2



    	 



    

 


 


IN WITNESS WHEREOF, the
parties hereto have caused this Amendment No. 1 to be duly executed by their respective authorized signatories as of the date first
indicated above.


 


	 	Arno Therapeutics, inc.
	 	 	 
	 	By:	 
	 	 	Name:Glenn R. Mattes
	 	 	Title: President & Chief Executive Officer


 


[REMAINDER OF PAGE INTENTIONALLY LEFT BLANK


SIGNATURE PAGES FOR PURCHASERS FOLLOW]


 



    	 



    	 



    

 


[PURCHASER
SIGNATURE PAGES TO


amendment
no. 1 to ARNI SECURITIES PURCHASE AGREEMENT]


 


IN WITNESS WHEREOF,
the undersigned have caused this Amendment No. 1 to be duly executed by their respective authorized signatories as of the date
first indicated above.


 


	Name of Purchaser:	 


 


	Signature of Authorized Signatory of Purchaser:	 


 


	Name of Authorized Signatory:	 


 


	Title of Authorized Signatory:	 


 


[SIGNATURE PAGES CONTINUE]