October 29, 2013	EXHIBIT 10.5







 


OPKO Health, Inc.


4400 Biscayne Boulevard


Miami, Florida 33137


Attention: Mr. Steven Rubin


 


	Re:	Subscription to Purchase Common Stock and Warrants of Arno 
	 	Therapeutics, Inc. (“Arno” or the “Company”)


 


Dear Mr. Rubin:


 


In connection with the offering (the “Offering”)
of shares of common stock, par value $0.0001 per share, (the “Common Stock”); Class C Warrants and Class D Warrants
(the “Warrants” and collectively with the Common Stock, the “Securities”) of Arno, we understand that OPKO
Health, Inc. (“OPKO”) will invest a minimum of $2.0 million, (the “OPKO Investment”) upon the terms and
conditions set forth in the Offering Documents (as defined below). We further understand that the Frost Group, LLC (“Frost
Group”), together with certain of its affiliates and associates, intends to invest an additional approximately $3 million
pursuant to the Offering (collectively with the OPKO Investment, the “Investment”). As such, in order to induce the
Frost Group and OPKO to make the Investment, and in addition to the representations, warranties and covenants contained in the
Offering Documents, Arno has agreed to enter into this Letter Agreement (the “Letter”). Capitalized terms used herein
but not otherwise defined in this Letter shall have the definition ascribed to such term in the Securities Purchase Agreement,
Registration Rights Agreement and form of Warrant (collectively, the “Offering Documents”).


 


1.          Following
the closing of the Offering and continuing until the date that OPKO shall collectively beneficially own less than 3% of the total
outstanding shares of Arno’s common stock calculated on a fully-diluted basis (i.e., assuming the issuance of all shares
underlying outstanding options, warrants and other rights to acquire common stock), subject to the Frost Group (or its affiliates
and associates) and OPKO making the Investment, Arno hereby agrees as follows:


 


(a)          Board
Observation Rights. OPKO shall have the right to designate one individual to serve as an observer to all meetings of the Board
of Directors of Arno. The observer nominee will be entitled to notice of meetings of the board, but shall not otherwise have any
rights of a director and shall have no right to vote on any matter presented to the Board for consideration. Such nominee shall
be required to enter into a written confidentiality agreement and shall be subject to Arno’s insider trading and other applicable
corporate policies, including without limitation, any communications policy in effect from time to time. Notwithstanding the foregoing,
the Board of Directors of Arno reserves the right to withhold any information and to exclude such designee from any meeting of
the board (or any portion thereof, including without limitation any executive sessions) if access to such information or attendance
at such meeting could adversely affect the attorney-client privilege between the Company and its counsel, present a conflict of
interest between the OPKO (and its affiliates) and the Company, or result in disclosure of a trade secret.


 


200 Route 31 North, Suite 104, Flemington,
NJ 08822


Tel: 862-703-7170 / Fax: 973-267-0101


 




    	 



    	 



    

 





 


(b)          Right
of First Negotiation. 


 


(i)          In
the event that the Board of Directors of Arno elects to pursue a Strategic Transaction (as defined below), Arno will provide written
notice to OPKO of such intent (the “Negotiation Notice”). Similarly, OPKO may initiate an Exclusivity Period by providing
a Negotiation Notice to the Chief Executive officer of Arno stating its desire to engage in negotiations with Arno relating to
a Strategic Transaction. Following delivery of any Negotiation Notice, OPKO shall have a period of 45 days (the “Exclusivity
Period”) during which OPKO shall have the exclusive right to negotiate a Strategic Transaction with Arno. During the Exclusivity
Period, Arno agrees not to solicit or propose terms to a third party regarding a Strategic Transaction, provided, however,
that Arno may engage lawyers, bankers and other consultants and advisors to assist it negotiating with OPKO. If by the expiration
of the Exclusivity Period, the parties have not entered into definitive agreements relating to a Strategic Transaction, then neither
party will have any further obligations to the other with respect to a Strategic Transaction and Arno shall be free to pursue a
Strategic Transaction with any third party as it may deem appropriate, with no further obligation to OPKO.


 


(ii)         During
any Exclusivity Period, and for a period of 90 days thereafter, the Frost Group will not sell, offer for sale, sell short, “short
against the box” or otherwise dispose of or enter into any agreement to dispose of any of the equity security of the Company
that it then owns or has the right to acquire, including without limitation the Common Stock, the Warrants and the shares of Common
Stock issuable upon exercise of the Warrants.


 


(iii)        For
purposes of this Letter, a “Strategic Transaction” shall mean (A) the sale or transfer of 50% of more of the outstanding
voting capital stock of the Company, (B) the sale, lease, transfer, exclusive license or other disposition, in a single transaction
or series of related transactions, by the Company of all or substantially all the assets of the Company, or the sale or disposition
(whether by merger or otherwise) of one or more subsidiaries of the Company if substantially all of the assets of the Company and
its subsidiaries taken as a whole are held by such subsidiary or subsidiaries, except where such sale, lease, transfer, exclusive
license or other disposition is to a wholly owned subsidiary of the Company, (C) the consolidation, merger or reorganization of
the Company into or with any other entity, in which the Company is not the surviving or resulting entity and in which the stockholders
of the Company existing prior to the transaction hold less than fifty percent (50%) of the outstanding voting capital stock of
the Company or the surviving or resulting entity, as applicable, immediately following such transaction, or (D) the sale, lease,
transfer, exclusive license or other disposition to a third party of any one or more of the Company’s existing products and/or
technologies, including without limitation; (i) onapristone, (ii) any companion diagnostic to onapristone; (iii) AR-12; and (iv)
AR-42.


 


2.          Access
to Information. The Company shall afford the officers, employees and authorized representatives of the OPKO reasonable access
to the senior management, business and financial records of the Company and its subsidiaries (including quarterly and annual financial
statements, but only to the extent such information is not available via the United States Securities and Exchange Commission’s
EDGAR system). In addition, at least twice each fiscal year representatives of OPKO shall be afforded the opportunity to meet with
the senior management of the Company at a mutually agreeable time and place to review the Company’s business and financial
condition. As a condition to OPKO’s rights under this paragraph and to the extent any material non-public information is
disclosed to it, OPKO and its affiliates, including without limitation, the Frost Group, shall agree in writing to maintain such
information in confidence and not to engage in any transactions involving the Company’s securities until the public disclosure
of such information.


 


200 Route 31 North, Suite 104, Flemington,
NJ 08822


Tel: 862-703-7170 / Fax: 973-267-0101


 




    	 



    	 



    

 





 


3.          Amendments
and Waivers. This Letter may be amended and the observance of any provision may be waived (either generally or in a particular
instance and either retroactively or prospectively) only with the mutual written consent of each of the parties hereto.


 


4.          Governing
Law. This Letter shall be governed by and construed under the laws of the State of Delaware.


 


5.          Counterparts.
This Letter may be executed in two or more counterparts, each of which shall be deemed an original, but all of which together shall
constitute one and the same instrument.


 


If the foregoing accurately reflects your
understanding of the proposed additional conditions to your Investment in the Offering, please countersign in the space below and
return a fully-executed copy of this Letter to my attention.


 


	 	Yours truly,
	 	Arno Therapeutics, Inc.
	 	 
	 	  /s/ Glenn R. Mattes
	 	Glenn R. Mattes
	 	President and Chief Executive Officer


 


	Agreed and accepted as of this __	 	Agreed and accepted as of this __
	day of October, 2013:	 	day of October, 2013:
	 	 	 
	FROST GROUP, LLC	 	OPKO Health, Inc. 
	 	 	 
	By:	/s/ Steven D. Rubin	 	By:	/s/ Kate Inman
	Name: Steven D. Rubin	 	Name: Kate Inman
	Title: Member	 	Title: Secretary
	Date: 10/29/2013	 	Date 10/29/2013


 


200 Route 31 North, Suite 104, Flemington,
NJ 08822


Tel: 862-703-7170 / Fax: 973-267-0101