Exhibit 4.3


 


RITTER PHARMACEUTICALS, INC. 



AMENDMENT NO. 1 TO



AMENDED AND RESTATED INVESTORS’ RIGHTS AGREEMENT


 


This Amendment No. 1 (the
“Amendment”) to the Amended and Restated Investors’ Rights Agreement dated as of November 17, 2010 (the
“Original Agreement”), is made and entered into as of January 13, 2011, pursuant to Section 6.1 of the Original
Agreement by and among Ritter Pharmaceuticals, Inc., a Delaware corporation (the “Company”), and the investors
listed on Exhibit A thereto (the “Investors”) holding a majority of the Company’s Registrable Securities
(as defined in the Original Agreement). 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
is a party to that certain Research and Development Agreement & License and that certain Put and Call Option Agreement, each
dated as of November 17, 2010 (together, the “R&D Agreement”), pursuant to which the Company must provide
Kolu Pohaku Management, LLC (“KPM”), with the right to designate one of the Company’s “Series B
Designees” (as defined in the IRA) upon “Disbursements” (as defined in the R&D Agreement) to the Company
of at least $750,000;


 


WHEREAS, the Company
anticipates that it shall receive the requisite Disbursements in January 2011;


 


WHEREAS, the Board
of Directors of the Company (the “Board”) has determined that it would be in the best interests of the Company
and its stockholders to amend the IRA in the manner set forth below; and


 


WHEREAS, the undersigned
represent the Company and stockholders holding at least a majority of the outstanding Registrable Securities of the Company as
of the date hereof;


 


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


 


AGREEMENT


 


1.      
Effective immediately upon the Company’s receipt of at least $750,000 in Disbursements pursuant to the R&D
Agreement, Section 541(b)(iii) of the Original Agreement shall be amended and restated to read as follows:


 


“(iii)   the
one “Series B Designee” shall be nominated by Kolu Pohaku Management, LLC, or an affiliate thereof (“KPM”),
and chosen by a majority-in-interest of the holders of outstanding shares of the Company’s Series B Preferred.”


 


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


 




    	 



    	 



    

 


3.
      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.


 


4.
      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.


 


5.
      This Amendment shall be governed by and construed and enforced in accordance with the
laws of the state of California, 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.


 


	 	“COMPANY”
	 	 
	 	RITTER PHARMACEUTICALS, INC.
	 	 
	 	By:	/s/ Andrew Ritter
	 	 	Andrew Ritter, Chief Executive Officer


 


Signature Page to Amendment No. 1 to


Amended and Restated Investors’
Rights Agreement


 




    	 



    	 



    

 


	 	“INVESTORS”
	 	 
	 	STONEHENGE PARTNERS, LLC
	 	 
	 	By:	/s/ Ira Ritter
	 	 	Ira Ritter, its Managing Member


 


Signature Page to Amendment No. 1 to


Amended and Restated Investors’
Rights Agreement