Exhibit 4.9


 


STOCKHOLDERS AGREEMENT


 


THIS STOCKHOLDERS AGREEMENT
(the “Agreement”) is made effective as of December 31, 2009, by and among the individuals listed on the signature page
and Exhibit A, and such other persons who shall become parties pursuant to the terms hereof (collectively, the “Stockholders”;
individually, a “Stockholder”) and Cancer Prevention Pharmaceuticals, Inc., a Delaware corporation (the “Corporation”).


 


RECITALS


 


The Stockholders and
the Corporation desire for their mutual benefit and protection to enter into an agreement for the continuity and stability of the
business and policies of the Corporation, and to that end, the Corporation and the Stockholders hereby set forth their agreement
with respect to the Stockholder Shares (as defined below) that are owned or may be acquired by the Stockholders.


 


NOW, THEREFORE, in
consideration of the mutual covenants contained herein, and other good and valuable consideration, the receipt and sufficiency
of which are hereby acknowledged, the Stockholders and the Corporation hereby agree as follows:


 


Section 1.            Definitions.


 


As used in this Agreement,
the following terms shall have the meanings ascribed to them below:


 


“Agreement”
means this Stockholders Agreement.


 


“Board”
means, with respect to the Corporation, the board of directors of the Corporation.


 


“Common Stock”
means, collectively the Common Stock, and any other class of capital stock of the Corporation authorized after the date hereof,
that is not entitled to at least a fixed sum or stated value in respect of the rights of the holders thereof to participate in
dividends or in the distribution of assets upon any liquidation, dissolution or winding up of the Corporation.


 


“Corporation”
has the meaning set forth in the caption to this Agreement.


 


“Convertible
Securities” means any stock or securities convertible, directly or indirectly, into or exchangeable for Common Stock.


 


“Equity Securities”
means all shares of capital stock of the Corporation, all securities convertible into or exchangeable for shares of capital stock
of the Corporation, and all options, warrants, and other rights to purchase or otherwise acquire from the Corporation shares of
such capital stock, or securities convertible into or exchangeable for shares of such capital stock.


  




     

     


    

  


“Permitted
Transferee” shall mean and include (i) another Stockholder, (i) a Stockholder’s spouse, (iii) a Stockholder’s
lineal descendants or ancestors (and their spouses), (iv) a trustee of a trust for the principal benefit of a Stockholder or a
person described in (ii) or (iii), (v) upon death of the Stockholder or of a Permitted Transferee of a Stockholder, his or her
respective heirs, administrators and executors, or (vi) an entity a majority of the outstanding equity interests of which are owned
by such Stockholder or Permitted Transferee.


 


“Person”
shall be construed broadly and shall include, without limitation, an individual, a partnership, an investment fund, a limited liability
company, a corporation, an association, a joint stock company, a trust, a joint venture, an unincorporated organization and a governmental
entity or any department, agency or political subdivision thereof.


 


“Public Offering”
means, with respect to any Person, the sale, in an underwritten public offering registered under the Securities Act, of shares
of the capital stock of such Person.


 


“Qualified
Public Offering” shall mean an initial Public Offering of Common Stock underwritten on a firm commitment basis which
results in aggregate net cash proceeds to the Corporation of not less than $30,000,000 and based upon a valuation of the Corporation
(prior to the consummation of such transaction) of at least $60,000,000.


 


“Securities
Act” means the Securities Act of 1933, as the same may be amended or supplemented from time to time, or any successor
statute, and the rules and regulations thereunder, as the same are from time to time in effect.


 


“Stockholder”
means any Person (whether as of the date hereof or hereafter) who executes this Agreement as a Stockholder, or any other person
which or who has executed a Stockholder Joinder.


 


“Stockholder
Joinder” means a joinder agreement, substantially in the form of Exhibit B hereto, by which a Person may have become
or may in the future become a Stockholder on or after the date hereof.


 


“Stockholder
Shares” means (i) any Common Stock purchased or otherwise acquired by any Stockholder, (ii) any Common Stock issued upon
the exercise or conversion of any Convertible Securities, and (iii) any Equity Securities issued or issuable directly or indirectly
with respect to the Common Stock referred to in clause (i) and clause (ii) above by way of stock dividend or stock split or in
connection with a combination of shares, recapitalization, merger, consolidation or other reorganization. For purposes of this
Agreement, holders of any portion of any Convertible Securities shall be deemed to be holders of Stockholder Shares issuable upon
exercise of such Convertible Securities and therefore shall be subject to the provisions and restrictions of this Agreement. As
to any particular shares constituting Stockholder Shares, such shares will cease to be Stockholder Shares when they have been effectively
registered under the Securities Act and disposed of in accordance with the registration statement covering them.


 


“Termination
Date” means the date of consummation of any Qualified Public Offering or liquidation of the Corporation.


 




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“Transfer”
means the sale, transfer, assignment, pledge or other disposal (whether with or without consideration and whether voluntarily or
involuntarily or by operation of law) of any interest in any Stockholder Shares.


 


Section 2.           Limitations
on Transfers


 


No Transfer of any
Stockholder Shares before the Termination Date shall become effective unless and until the transferee executes and delivers to
the Corporation a counterpart to this Agreement in the form of a Stockholder Joinder, agreeing to be treated in the same manner
as the transferring Stockholder. Upon such Transfer and such execution and delivery, the transferee shall be bound by, and entitled
to the benefits of, this Agreement with respect to the transferred Stockholder Shares.


 


Section 3.           Transfer
of Stockholder Shares


 


3.1         Right
of First Refusal. In addition to any requirements set forth below, Transfers of Stockholder Shares will be subject to a right
of first refusal as follows: before any Stockholder Shares may be sold or transferred (including transfer by operation of law),
the holder of such Stockholder Shares (“Selling Stockholder”) shall first offer such Stockholder Shares to the Corporation
and the other Stockholders in accordance with the following terms and conditions:


 


A.        The
Selling Stockholder shall deliver a notice (the “Notice”) to the Board and the other Stockholders stating (i) its bona
fide intention to sell or transfer such Stockholder Shares; (ii) the price for which its proposes to sell or transfer such Stockholder
Shares; and (iii) the name of the proposed purchaser or transferee. A copy of a written offer from the proposed purchaser or transferee
shall be attached to the Notice.


 


B.        Within
thirty (30) days after receipt of the Notice, the Board may elect to cause the Corporation to purchase all or any portion of the
Stockholder Shares to which the Notice refers on the same terms and conditions specified in the Notice.


 


C.        If
the Corporation does not elect to purchase the Stockholder Shares in question, then within sixty (60) days after receipt of the
Notice, the other Stockholders may elect to purchase all or any portion of the Stockholder Shares to which the Notice refers, on
the same terms and conditions specified in the Notice. In the event that more than one Stockholder wishes to purchase the Stockholder
Shares being offered, each of the Stockholders desiring to purchase the Stockholder Shares shall be entitled to purchase a proportionate
share of the Stockholder Shares in the same ratio as the number of shares of Common Stock owned by each of them bears to the number
of shares of Common Stock owned by all of them.


 


D.        If
all of the Stockholder Shares to which the Notice refers are not purchased as provided in Paragraphs B and C immediately above,
the Selling Stockholder may sell the Stockholder Shares that were not purchased to the person named in the Notice at the price
specified in the Notice or at a higher price, provided that:


 




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(1)         such
sale or transfer is consummated within ninety (90) days of the date of the Notice;


 


(2)         any
such sale is in accordance with all the terms and conditions hereof;


 


(3)         the
Stockholder Shares sold pursuant hereto will remain subject to the terms hereof to the same extent as if such Stockholder Shares
had not been sold by the Selling Stockholder; and


 


(4)         Unless
waived by the Corporation, the Selling Stockholder shall deliver to the Corporation an opinion of counsel, in form acceptable to
counsel to the Corporation that:


 


(a)       The
proposed Transfer of the Stockholder Shares will comply with all federal and state laws and regulations, including the Securities
Act; and


 


(b)       The
proposed Transfer will not affect the availability to the Corporation of the exemption from registration of the Stockholder Shares
provided by Regulation D promulgated by the Securities and Exchange Commission under Section 4(2) of the Securities Act or any
similar exemption from registration under federal law or any applicable state blue sky laws.


 


(c)       The
proposed purchaser or transferee shall deliver to the Corporation an investment letter, in form acceptable to the Board, stating
that such proposed purchaser or transferee is acquiring the Stockholder Shares in the Corporation for investment purposes only
and not for the purpose of reselling or otherwise distributing such Stockholder Shares to the public.


 


E.         An
offer shall be accepted by giving notice of acceptance to the party giving notice of the offer. If acceptance is by the Corporation,
notice of acceptance shall be given concurrently to the Stockholders. If the acceptance is by one or more of the Stockholders other
than the Selling Stockholder, notice of the acceptance shall be given concurrently to the Corporation and to all Stockholders.


 


F.         Reimbursement
of Expenses. The Selling Stockholder shall reimburse the Corporation for all expenses, including, without limitation, legal
fees, connected with such Transfer.


 


3.2        Permitted
Transferee. The provisions of Section 3.1 shall not apply to a proposed Transfer to a Permitted Transferee.


 


Section 4.           Involuntary
Transfer


 


If Stockholder Shares
are to be purchased pursuant to an offer that is the result of a proposed transfer pursuant to a judicial or private sale under
writ of execution or foreclosure of a security in the Stockholder Shares, the price to be paid shall be the total amount required
to redeem the Stockholder Shares and discharge or satisfy the judicial process or security agreement. If the Corporation or the
Stockholders purchase the Stockholder Shares under the circumstances described in this subsection, the Selling Stockholder shall
have a period of sixty (60) days after such purchase within which to redeem the shares by repayment to the Corporation or the Stockholders
of the amount paid for the Stockholder Shares plus any other costs, including attorney’s fees, incurred by the Corporation
or the Stockholders in the making of such purchase, plus Stockholder Shares on the amount paid and costs incurred at the rate of
ten percent (10%) per annum from the date of payment.


  




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Section 5.           Additional
Restrictions on Transfer of Stockholder Shares


 


5.1         Legend.
The certificates representing the Stockholder Shares shall bear a legend substantially in the following form:


 


THE SECURITIES REPRESENTED BY
THIS CERTIFICATE HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, THE ARIZONA SECURITIES ACT OR THE SECURITIES LAWS OF
ANY OTHER STATE OR JURISDICTION. THEY MAY NOT BE PURCHASED WITH A VIEW FOR DISTRIBUTION OR RESALE, AND MAY ONLY BE OFFERED, SOLD,
MORTGAGED, PLEDGED, HYPOTHECATED, OR OTHERWISE TRANSFERRED IN COMPLIANCE WITH EITHER AN EFFECTIVE REGISTRATION STATEMENT FOR SUCH
SECURITY UNDER THE SECURITIES ACT OF 1933 OR ANY APPLICABLE STATE SECURITIES ACT, OR AN OPINION OF COUNSEL FOR THE CORPORATION
THAT REGISTRATION IS NOT REQUIRED UNDER SUCH ACT OR THE LAWS OF ANY OTHER JURISDICTION. THIS CERTIFICATE SHALL BE REGISTERED ON
THE BOOKS OF THE CORPORATION WITH “STOP TRANSFER” INSTRUCTIONS, THUS PRECLUDING FUTURE UNREGISTERED TRANSFER.


 


THE HOLDER OF THESE SECURITIES
IS SUBJECT TO A STOCKHOLDERS AGREEMENT DATED DECEMBER 31, 2009 BETWEEN THE CORPORATION AND CERTAIN STOCKHOLDERS OF THE CORPORATION
AND, EXCEPT AS PROVIDED IN SUCH AGREEMENT, THE TRANSFEREE OF THE SECURITIES REPRESENTED BY THIS CERTIFICATE MUST AGREE TO BE BOUND
BY THE TERMS OF SUCH STOCKHOLDERS AGREEMENT AS A CONDITION OF TRANSFER.


 


5.2         Transfers
in Violation of Agreement. Any Transfer or attempted Transfer of any Stockholder Shares in violation of any provision of this
Agreement shall be void, and the Corporation shall not record such Transfer on its books or treat any purported transferee of such
Stockholder Shares as the owner of such Stockholder Shares for any purpose.


 


5.3         Pledges.
Notwithstanding any provision in this Agreement to the contrary, no holder of Stockholder Shares may pledge any Stockholder Shares
on or after the date hereof.


 


 




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Section 6.           Binding
Effect; Joinders; Additional Shares


 


6.1        Any
transferee of Stockholder Shares from a Stockholder (other than the Corporation or another Stockholder) shall, as a condition to
such Transfer, be deemed a Stockholder for purposes of this Agreement and be bound by and subject to the terms and provisions of
this Agreement applicable to Stockholders, and if not already a signatory to this Agreement as a Stockholder, such Person shall
execute and deliver to the Corporation a Stockholder Joinder.


 


6.2        In
the event additional Stockholder Shares are issued by the Corporation to a Stockholder at any time during the term of this Agreement,
such additional Stockholder Shares shall, as a condition to such issuance, be deemed subject to the terms and provisions of this
Agreement.


 


Section 7.           No
Conflicting Agreements


 


No Stockholder shall
enter into any stockholder agreements or arrangements of any kind with any Person with respect to any Stockholder Shares on terms
inconsistent with the provisions of this Agreement (whether or not such agreements or arrangements are with other Stockholders
or with Persons that are not parties to this Agreement), including, but not limited to, agreements or arrangements with respect
to the acquisition or disposition of Stockholder Shares in a manner that is inconsistent with this Agreement.


 


Section 8.           Further
Assurances


 


Each party hereto shall
do and perform or cause to be done and performed all such further acts and things and shall execute and deliver all such other
agreements, certificates, instruments and documents as any other party hereto reasonably may request in order to carry out the
provisions of this Agreement and the consummation of the transactions contemplated hereby.


 


Section 9.           Termination



 


9.1        All
of the provisions of this Agreement shall terminate and, except as otherwise expressly provided herein, shall be of no further
force or effect and shall not be binding upon any party hereto, upon the first to occur of (A) the consummation of a Qualified
Public Offering and (B) the approval of such termination by the Corporation and the holders of seventy-five percent (75%) of the
Stockholder Shares.


 


9.2        As
to any particular Stockholder, this Agreement shall no longer be binding or of further force or effect as to such Stockholder,
except as otherwise expressly provided herein, as of the date such Stockholder has transferred all such Stockholder's Stockholder
Shares and each transferee of such Stockholder Shares shall have become a party hereto; provided, however, that no such termination
shall be effective if such Stockholder is in breach of this Agreement immediately before or after giving effect to such Transfer(s).


 




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Section 10.           General
Provisions


 


10.1        Amendment;
Waiver and Release. Except as otherwise provided herein, no modification, amendment or waiver of any provision of this Agreement
shall be effective unless such modification, amendment or waiver is approved in writing by all of the Stockholders of the Corporation.
The failure of any party to enforce any of the provisions of this Agreement shall in no way be construed as a waiver of such provisions
and shall not affect the right of such party thereafter to enforce each and every provision of this Agreement in accordance with
its terms.


 


Notwithstanding the above,
amendments may be made to this Agreement from time to time by the Board without the consent of the Stockholders only to cure any
ambiguity or correct or supplement any provision hereunder which may be inconsistent with any other provision hereunder provided
that such amendment is for the benefit of the Stockholders.


 


10.2        Severability.
It is the desire and intent of the parties hereto that the provisions of this Agreement be enforced to the fullest extent permissible
under the laws and public policies applied in each jurisdiction in which enforcement is sought. Accordingly, if any particular
provision of this Agreement shall be adjudicated by a court of competent jurisdiction to be invalid, prohibited or unenforceable
for any reason, such provision, as to such jurisdiction, shall be ineffective, without invalidating the remaining provisions of
this Agreement or affecting the validity or enforceability of this Agreement or affecting the validity or enforceability of such
provision in any other jurisdiction. Notwithstanding the foregoing, if such provision could be more narrowly drawn so as not to
be invalid, prohibited or unenforceable in such jurisdiction, it shall, as to such jurisdiction, be so narrowly drawn, without
invalidating the remaining provisions of this Agreement or affecting the validity or enforceability of such provision in any other
jurisdiction.


 


10.3        Entire
Agreement.    Except as otherwise expressly set forth herein, this document embodies the complete agreement and understanding
among the parties hereto with respect to the subject matter hereof and supersedes and preempts any prior understandings, agreements
or representations by or among the parties, written or oral, which may have related to the subject matter hereof in any way.


 


10.4        Successors
and Assigns.    Except as otherwise provided herein, this Agreement shall bind and inure to the benefit of and be
enforceable by the Corporation and, so long as Stockholder Shares are held by such Person, each Person which or who was a Stockholder
on the date hereof and each Person which or who was or in the future becomes a Stockholder, subsequent to that date, shall not
assign or transfer Stockholder Shares unless such Stockholder shall comply with this Agreement. None of the provisions hereof shall
create, or be construed or deemed to create, any right of employment in favor of any Person by the Corporation or any of its Subsidiaries.
This Agreement is not intended to create any third party beneficiaries.


 


10.5        Counterparts. 
This Agreement may be executed in separate counterparts each of which shall be an original and all of which taken together shall
constitute one and the same agreement.


 




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10.6        Remedies.
The Corporation and the Stockholders shall be entitled to enforce their rights under this Agreement specifically to recover damages
by reason of any breach of any provision of this Agreement and to exercise all other rights existing in their favor. The Corporation
and the Stockholders agree and acknowledge that money damages may not be an adequate remedy for any breach of the provisions of
this Agreement and that the Corporation and any Stockholder may in its sole discretion apply to any court of law or equity of competent
jurisdiction for specific performance and/or injunctive relief (without posting a bond or other security) in order to enforce or
prevent any violation of the provisions of this Agreement.


 


10.7        Notices.
All notices, requests, demands, claims, and other communications hereunder shall be in writing and shall be deemed to have been
duly given if delivered personally, by facsimile, sent by nationally recognized overnight courier or mailed by registered or certified
mail (return receipt requested), postage prepaid, to the parties at the following addresses (or at such other address for a party
as shall be specified by like notice):


 


(i)       If
to the Corporation, to:


Cancer Prevention Pharmaceuticals,
Inc.


1760 E. River
Road, Suite 250


Tucson, AZ 
85718


 


with a copy to:


Hecker & Muehlebach, PLLC


Rockwell Building


405 West
Franklin Street


Tucson, AZ
85701-8209


Attention: Lawrence M. Hecker


Telephone: (520) 798-3803


Fax: (520) 620-0405


 


(ii)     If
to a Stockholder set forth on Schedule A hereto, to the related address or facsimile number set forth on Schedule A hereto.


 


(iii)     If
to a Stockholder not set forth on Schedule A hereto, to the related address or facsimile number set forth in the Stockholder Joinder
executed and delivered by such Stockholder to the Corporation.


 


All such notices and
other communications shall be deemed to have been given and received (a) in the case of personal delivery or delivery by facsimile,
on the date of such delivery, (b) in the case of delivery by nationally recognized overnight courier, on the third (3rd)
business day following such dispatch and (c) in the case of mailing, on the seventh (7th) business day following such
mailing.





 




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10.8        GOVERNING
LAW.    THIS AGREEMENT WILL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE DOMESTIC LAWS OF THE STATE OF ARIZONA,
WITHOUT GIVING EFFECT TO ANY CHOICE OF LAW OR CONFLICTING PROVISION OR RULE (WHETHER OF THE STATE OF ARIZONA, OR ANY OTHER JURISDICTION)
THAT WOULD CAUSE THE LAWS OF ANY JURISDICTION OTHER THAN THE STATE OF ARIZONA TO BE APPLIED, EXCEPT TO THE EXTENT THAT THIS AGREEMENT
RELATES TO THE INTERNAL AFFAIRS OF THE CORPORATION, WHICH SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE
STATE OF ARIZONA WITHOUT GIVING EFFECT TO ANY CHOICE OF LAW OR CONFLICTING PROVISION OR RULE (WHETHER OF THE STATE OF ARIZONA OR
ANY OTHER JURISDICTION) THAT WOULD CAUSE THE LAWS OF ANY JURISDICTION OTHER THAN THE STATE OF ARIZONA TO BE APPLIED TO SUCH MATTERS.
IN FURTHERANCE OF THE FOREGOING, THE INTERNAL LAW OF THE STATE OF ARIZONA WILL CONTROL THE INTERPRETATION AND CONSTRUCTION OF THIS
AGREEMENT, EVEN IF UNDER SUCH JURISDICTION'S CHOICE OF LAW OR CONFLICT OF LAW ANALYSIS, THE SUBSTANTIVE LAW OF SOME OTHER JURISDICTION
WOULD ORDINARILY APPLY.


 


10.9        Descriptive
Headings. The descriptive headings of this Agreement are inserted for convenience only and do not constitute a part of this
Agreement.


 


10.10        Construction
  Where specific language is used to clarify by example a general statement contained herein, such specific language shall
not be deemed to modify, limit or restrict in any manner the construction of the general statement to which it relates. The language
used in this Agreement shall be deemed to be the language chosen by the parties to express their mutual intent, and no rule of
strict construction shall be applied against any party.


 


10.11       Waiver
of Jury Trial. EACH OF THE PARTIES HERETO HEREBY IRREVOCABLY WAIVES ALL RIGHT TO TRIAL BY JURY IN ANY ACTION, PROCEEDING OR
COUNTERCLAIM ARISING OUT OF OR RELATING TO THIS AGREEMENT.


 


10.12       Nouns
and Pronouns. Whenever the context may require, any pronouns used herein shall include the corresponding masculine, feminine
or neuter forms, and the singular form of nouns and pronouns shall include the plural and vice-versa.


 


IN WITNESS WHEREOF,
the parties hereto have executed this Stockholders Agreement on the day and year first above written.


 


[signature page follows]





 




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[signature page to Cancer Prevention
Pharmaceuticals Stockholders Agreement


of December 31, 2009]


 


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


 


Stockholders:


 


	Meyskens Pharmaceutical Investors, LLC	 	Gerner Pharmaceutical Investors, LLC,
	 	 	 
	/s/ Frank Meyskens	 	/s/ Eugene Gerner
	Frank Meyskens	 	Eugene Gerner
	Co-Founder	 	 
	Title	 	Title
	 	 	 
	 	 	 
	The Tierney Family Trust	 	 
	 	 	 
	/s/ Thomas T. Tierney	 	/s/ Jeffrey Jacob
	Thomas T. Tierney, Trustee	 	Jeffrey Jacob
	 	 	 
	/s/
    Elizabeth C. Tierney	 	/s/
    Deborah Jacob
	Elizabeth C. Tierney, Trustee	 	Spouse


 




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EXHIBIT
A


 


STOCKHOLDERS


 


	1.	Meyskens Pharmaceutical Investors, LLC, an Arizona limited liability company
	2.	Gerner Pharmaceutical Investors, LLC, an Arizona limited liability company
	3.	The Tierney Family Trust, Thomas T. or Elizabeth C. Tierney as Trustees, (“Tierney”)
	4.	Jeffrey Jacob (“Jacob”).


 




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EXHIBIT B


 


STOCKHOLDER JOINDER


 


By execution of this
Stockholder Joinder, the undersigned agrees to become a party to that certain Stockholders Agreement dated as of December 31, 2009
(as the same may be amended, supplemented or otherwise modified from time to time, the “Stockholders Agreement”), among
Cancer Prevention Pharmaceuticals, Inc., a Delaware corporation, and certain of its stockholders. The undersigned shall have all
the rights, and shall observe all the obligations, applicable to a Stockholder (as defined in the Stockholders Agreement).


 


	Name:  	 	 


 


 


	Address for Notices:	 	With copies to:
	 	 	 
	 	 	 
	 	 	 
	 	 	 
	 	 	 
	 	 	 
	 	 	 
	 	 	 


 


	Signature:	 	 


 


	Date:	 	 


  




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