Exhibit 10.21


 


RITTER PHARMACEUTICALS,
INC.


 


AMENDMENT NO. 4 TO


 


RESEARCH AND DEVELOPMENT
AGREEMENT & LICENSE


 


This Amendment No. 4 (the
“Amendment”) to the Research and Development Agreement & License, dated as of November 17, 2010, and amended
on July 6, 2011, September 30, 2011 and February 6, 2012 (as amended to date, the “Original Agreement”), is
made and entered into as of November 4, 2013, pursuant to Section 13.4 of the Original Agreement, by and among KOLU POHAKU TECHNOLOGIES,
LLC, a Delaware limited liability company (together with its successors and assigns, “Kolu Pohaku”);
KOLU POHAKU MANAGEMENT, LLC, a Delaware limited liability company (together with its successors and assigns, “KPM”);
and RITTER PHARMACEUTICALS, INC., a Delaware corporation (together with its successors and assigns., the “Company”).
Capitalized terms used in this Amendment that are not otherwise defined herein shall have the respective meanings assigned to them
in the Original. Agreement.


 


RECITALS


 


WHEREAS, the Company,
Kolu Pohaku and KPM are parties to the Original Agreement;


 


WHEREAS, the parties
wish to amend the Original Agreement in the manner set forth below in order to fund additional activities in accordance with the
terms of [he Original Agreement; and


 


WHEREAS, the Original
Agreement may be amended by written agreement of the parties thereto.


 


NOW, THEREFORE,
the parties hereto hereby agree as follows:


 


AGREEMENT


 


1.
       Section 2.15 is hereby amended and restated to read as follows:


 


   2.15   “R&D
Fee” means the installment payments by Kolu Pohaku described in Section 7, other than Section 7.4.


 


2.
       A new Section 7.4 shall be added to the Original Agreement reading as follows:


 


  7.4   2014
Fee. Kolu Pohaku shall pay to Researcher a fee (the “2014 Fee”) of One Hundred Fifty Thousand Dollars
($150,000.00) for activities that may include, but shall not limited to, KP Research, provided, however, that Researcher may not
utilize the 2014 Fee, or any portion thereof, prior to January 1, 2014, without Kolu Pohaku’s express written consent. Researcher
agrees that the 2014 Fee has been disbursed to Researcher in accordance with the Agreement (such amount, the “2014
Disbursement”) and shall be included, for all purposes, in the definition of Class 1 R&D Disbursements


 




    	 



    	 



    




 


set forth above.
Researcher further agrees that the payments set forth in the Agreement shall be full and complete compensation for all obligations
and deliverables by Researcher under this Agreement and for all inventions, developments and improvements assigned under this Agreement,
if any. Researcher specifically agrees that Kolu Pohaku shall not be responsible for any costs of overhead, salaries, materials
or other expenses, except as set forth herein.


 


3.
       Except as expressly set forth in this Amendment, the Original Agreement shall
continue in full force and effect in accordance with its terms.


 


4.
       This Amendment may be executed in one or more counterparts, each of which shall
be deemed an original, but all of which together shall constitute one and the same instrument,


 


5.
       All corporate action on the part of the Company and its directors, officers, and
stockholders necessary for the authorization, execution, and delivery of this Amendment by the Company has been taken as of the
date hereof.


 


6.
       This Amendment shall be governed by and construed and enforced in accordance with
the laws of the State of Hawaii, without reference to the conflict of laws provisions thereof.


 


(Signature pages follow)


 




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IN WITNESS WHEREOF, the
parties hereto have duly executed this Amendment as of the date first above written.


 


	 	KOLU POHAKU TECHNOLOGIES, LLC
	 	 
	 	By	/s/ Thomas Adamek
	 	 	Thomas Adamek, President
	 	 	 
	 	KOLU POHAKU MANAGEMENT, LLC
	 	 
	 	By	/s/ Thomas Adamek
	 	 	Thomas Adamek, President
	 	 	 
	 	RITTER PHARMACEUTICALS, INC.
	 	 
	 	By	/s/ Andrew J. Ritter
	 	 	Andrew Ritter, President and CEO