Exhibit 10.17


 


CANCER PREVENTION PHARMACEUTICALS,
INC.


 


AMENDMENT TO Right
of First Refusal and Co-Sale Agreement


 


This Amendment to Right
of First Refusal and Co-Sale Agreement (“Amendment”) is made as of September 27, 2012 by and between Cancer Prevention
Pharmaceuticals, Inc., a Delaware corporation (the “Company”) and the undersigned Investors and Founders. Capitalized
terms used but not otherwise defined herein shall have the meanings assigned to such terms in that certain Right
of First Refusal and Co-Sale Agreement dated as of September 17, 2012 between the Company and the Investors and Founders
(the “Agreement”).


 


WHEREAS, together, the
undersigned Investors and Founders and the Company are authorized and desire to amend the Agreement in the manner herein provided.


 


NOW THEREFORE, in consideration
of the mutual covenants, promises and agreements of the Company and the undersigned Investors and other good and valuable consideration,
the receipt and sufficiency of which are hereby acknowledged, the parties hereby agree as follows:


 


		1.	Amendment of Agreement. The Company and the undersigned Investors hereby amend the Agreement
in the manner set forth herein. Except as specifically provided herein, the terms of the Agreement shall remain in full force and
effect.



 


		2.	Recitals.



 


		A.	Recitals B, C, D, and E are hereby amended to read as
follows:



 


B.         Certain holders (“Note
Holders”) of the Company’s Convertible Promissory Notes (“Notes”) are desirous of converting,
or have converted, the principal amount of and accrued interest on the Notes into the Company’s Series A-1 Convertible Preferred
Stock (“Series A-1 Preferred”) in accordance with the terms of the Series A-1 Preferred Stock Purchase Agreement
(the “Conversion”).


 


C.         The Company proposes to
sell (“Financing”) shares of its Series A-2 Convertible Preferred Stock (“Series A-2 Preferred”)
to the purchasers identified on Series A-2 Preferred Stock Purchase Agreement (the “Purchase Agreement”).


 


D.        The Investors are, or
will be, either (i) former Note Holders which have been converted pursuant to the Conversion or (ii) purchasers of Series A-2 Preferred
listed in the Purchase Agreement.


 


		B.	The following Recital E is hereby added:



 


E.        As a condition to the
Financing and the Conversion, the Investors, Founders, and Company have agreed to enter into this Agreement.


 




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		3.	Section 1.1(l). Section 1.1(l) is hereby amended to read as follows:



 


(l)        “Series A
Preferred” means all shares of the Series A-1 Convertible Preferred Stock and Series A-2 Convertible Preferred Stock..


 


		4.	Section 8.4 Amendment. Section 8.4 is hereby amended to read as follows:



 


8.4        Amendment. Except
as expressly provided herein, neither this Agreement nor any term hereof may be amended, waived, discharged or terminated other
than by a written instrument referencing this Agreement and signed by the Company and the Investors holding a majority of the Common
Stock issued or issuable upon conversion of the Preferred Stock (excluding any of such shares that have been sold to the public
or pursuant to Rule 144); provided, however, that Investors purchasing Shares in a Closing after the Initial Closing (as such terms
are defined in the Purchase Agreement) may become parties to this Agreement by executing a counterpart of this Agreement, without
any amendment of this Agreement pursuant to this paragraph or any consent or approval of any other Investor; and provided, further,
that if any amendment, waiver, discharge or termination operates in a manner that treats any Investor materially different from
other Investors, the consent of such Investor shall also be required for such amendment, waiver, discharge or termination; and
provided, further, that if any such amendment or waiver shall be to the material detriment of a Seller (when compared to the obligations
as to which Seller is already subject to under this Agreement), the consent of such Seller shall also be required. Any such amendment,
waiver, discharge or termination effected in accordance with this paragraph shall be binding upon each Seller, each Investor and
each future holder of shares of Preferred Stock with rights under this Agreement. Each Investor acknowledges that by the operation
of this paragraph, the holders of a majority of the Common Stock issued or issuable upon conversion of the Preferred Stock (excluding
any of such shares that have been sold to the public or pursuant to Rule 144) will have the right and power to diminish or eliminate
all rights of such Investor under this Agreement.


 


The parties are signing this Amendment to
Right of First Refusal and Co-Sale Agreement as of the date stated in the introductory clause.


 


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blank)


 




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Signature page to Amendment to
Right of First Refusal and Co-Sale Agreement of 


Cancer Prevention Pharmaceuticals,
Inc.


 


	Cancer Prevention Pharmaceuticals, Inc.	 
	 	 	 
	By:	/s/ Jeffrey Jacob     	 
	 	Jeffrey Jacob, CEO	 


 


	Stockholder	 	Signature	 	Series A-1

Preferred

Shares Held
	 	 	 	 	 
	Frank and Linda Meyskens	 	/s/ Frank Meyskens	 	61,045
	 	 	Frank Meyskens	 	 
	 	 	 	 	 
	Eugene and Sandra Gerner	 	/s/ Eugene Gerner	 	60,963
	 	 	Eugene Gerner	 	 
	 	 	 	 	 
	Jeffrey E. Jacob	 	/s/ Jeffrey Jacob	 	122,009
	 	 	Jeffrey Jacob	 	 
	 	 	 	 	 
	GDB Investments, LLP	 	/s/ Daniel Donovan	 	672,643
	 	 	Daniel Donovan	 	 
	 	 	 	 	 
	Translational Accelerator, LLC	 	/s/ Eric Tooker	 	2,021,853
	 	 	Eric Tooker	 	 


 


 


	Founder	 	Signature
	 	 	 
	Meyskens Pharmaceutical Investors, LLC	 	/s/
    Frank Meyskens
	 	 	Frank Meyskens
	 	 	 
	Gerner Pharmaceutical Investors, LLC	 	/s/
    Eugene Gerner
	 	 	Eugene Gerner
	 	 	 
	Jeffrey E. Jacob	 	/s/
    Jeffrey Jacob
	 	 	Jeffrey Jacob
	 	 	 
	Tierney Family Trust	 	/s/
    Thomas Tierney
	 	 	Thomas Tierney


 




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