Exhibit
4.13

     
 

    
      

    

    
        

      Company

        

      and

        

      Computershare
Trust Company, N.A.,

        

      Warrant
Agent

        

        
   

    

    Series B
Warrant Agreement

      


    Dated as
of _________, 2011
  

    
      
         


      

      
         


        
          

        

      

      
         


      

    

      

    TABLE OF
CONTENTS

      

    
      
        
          	 
      	 
      	 
      	 
      	
                  Page

                
	 
      	 
      	 
      	 
      	 
      
	
                  Section
      1.

                	 
      	
                  Certain
      Definitions

                	 
      	
                  1

                
	 
      	 
      	 
      	 
      	 
      
	
                  Section
      2.

                	 
      	
                  Appointment
      of Warrant Agent

                	 
      	
                  2

                
	 
      	 
      	 
      	 
      	 
      
	
                  Section
      3.

                	 
      	
                  Form
      of Warrant Certificates

                	 
      	
                  2

                
	 
      	 
      	 
      	 
      	 
      
	
                  Section
      4.

                	 
      	
                  Countersignature
      and Registration

                	 
      	
                  3

                
	 
      	 
      	 
      	 
      	 
      
	
                  Section
      5.

                	 
      	
                  Transfer,
      Split Up, Combination and Exchange of Warrant Certificates; Mutilated,
      Destroyed, Lost or Stolen Warrant Certificates

                	 
      	
                  3

                
	 
      	 
      	 
      	 
      	 
      
	
                  Section
      6.

                	 
      	
                  Exercise
      of Warrants; Exercise Price; Expiration Date

                	 
      	
                  4

                
	 
      	 
      	 
      	 
      	 
      
	
                  Section
      7.

                	 
      	
                  Cancellation
      and Destruction of Warrant Certificates

                	 
      	
                  7

                
	 
      	 
      	 
      	 
      	 
      
	
                  Section
      8.

                	 
      	
                  Certain
      Representations; Reservation and Availability of Shares of Common Stock or
      Cash

                	 
      	
                  8

                
	 
      	 
      	 
      	 
      	 
      
	
                  Section
      9.

                	 
      	
                  Common
      Stock Record Date

                	 
      	
                  9

                
	 
      	 
      	 
      	 
      	 
      
	
                  Section
      10.

                	 
      	
                  Adjustment
      of Exercise Price, Number of Shares of Common Stock or Number of the
      Company Warrants

                	 
      	
                  10

                
	 
      	 
      	 
      	 
      	 
      
	
                  Section
      11.

                	 
      	
                  Certification
      of Adjusted Exercise Price or Number of Shares of Common
    Stock

                	 
      	
                  13

                
	 
      	 
      	 
      	 
      	 
      
	
                  Section
      12.

                	 
      	
                  Reclassification,
      Consolidation, Purchase, Combination, Sale or Conveyance

                	 
      	
                  13

                
	 
      	 
      	 
      	 
      	 
      
	
                  Section
      13.

                	 
      	
                  Fractional
      Shares of Common Stock.

                	 
      	
                  14

                
	 
      	 
      	 
      	 
      	 
      
	
                  Section
      14.

                	 
      	
                  Agreement
      of Warrant Certificate Holders

                	 
      	
                  15

                
	 
      	 
      	 
      	 
      	 
      
	
                  Section
      15.

                	 
      	
                  Warrant
      Certificate Holder Not Deemed a Shareholder

                	 
      	
                  15

                
	 
      	 
      	 
      	 
      	 
      
	
                  Section
      16.

                	 
      	
                  Concerning
      the Warrant Agent.

                	 
      	
                  15

                
	 
      	 
      	 
      	 
      	 
      
	
                  Section
      17.

                	 
      	
                  Purchase
      or Consolidation or Change of Name of Warrant Agent

                	 
      	
                  17

                
	 
      	 
      	 
      	 
      	 
      
	
                  Section
      18.

                	 
      	
                  Duties
      of Warrant Agent

                	 
      	
                  17

                
	 
      	 
      	 
      	 
      	 
      
	
                  Section
      19.

                	 
      	
                  Change
      of Warrant Agent

                	 
      	
                  19

                


        

      

    

     

    
      
         


      

      
         


        
          

        

      

      
         


      

    

    


    
      
        
          
            
              
                
                  	 
      	 
      	 
      	 
      	
                          Page

                        
	 	 	 	 	 
	
                          Section
      20.

                        	 
      	
                          Issuance
      of New Warrant Certificates

                        	 
      	
                          20

                        
	 
      	 
      	 
      	 
      	 
      
	
                          Section
      21.

                        	 
      	
                          Covenants.

                        	 
      	
                          20

                        
	 
      	 
      	 
      	 
      	 
      
	
                          Section
      22.

                        	 
      	
                          Notices

                        	 
      	
                          20

                        
	 
      	 
      	 
      	 
      	 
      
	
                          Section
      23.

                        	 
      	
                          Supplements
      and Amendments

                        	 
      	
                          21

                        
	 
      	 
      	 
      	 
      	 
      
	
                          Section
      24.

                        	 
      	
                          Successors

                        	 
      	
                          22

                        
	 
      	 
      	 
      	 
      	 
      
	
                          Section
      25.

                        	 
      	
                          Benefits
      of this Agreement

                        	 
      	
                          22

                        
	 
      	 
      	 
      	 
      	 
      
	
                          Section
      26.

                        	 
      	
                          Governing
      Law

                        	 
      	
                          22

                        
	 
      	 
      	 
      	 
      	 
      
	
                          Section
      27.

                        	 
      	
                          Counterparts

                        	 
      	
                          22

                        
	 
      	 
      	 
      	 
      	 
      
	
                          Section
      28.

                        	 
      	
                          Captions

                        	 
      	
                          22

                        
	 
      	 
      	 
      	 
      	 
      
	
                          Section
      29.

                        	 
      	
                          Information

                        	 
      	
                          22

                        
	 
      	 
      	 
      	 
      	 
      
	
                          Section
      30.

                        	 
      	
                          Force
      Majeure

                        	 
      	
                          22

                        


                

              

            

          

        

      

    

    

      
        
           


        

        
           


          
            

          

        

        
           


        

      


      SERIES B WARRANT
AGREEMENT

       

      This
SERIES B WARRANT AGREEMENT (this “Agreement”), dated as of ____________, 2011,
is entered into among Repros Therapeutics Inc., a Delaware corporation (the
“Company”), Computershare, Inc., a Delaware corporation and its fully owned
subsidiary Computershare Trust Company, N.A., a national banking association
(collectively, the “Warrant Agent” or individually “Computershare” and the
“Trust Company,” respectively).

      


      W I T N E S S E T
H

       

      WHEREAS,
the Company, at or about the time that it is entering into this Agreement,
proposes to issue and sell to public investors Series B Warrants (the
“Warrants”) entitling the holder or holders thereof to purchase an aggregate of
1,690,500 shares of common stock, par value $.001 per share, of the Company (the
“Common Stock”) upon the terms and subject to the conditions hereinafter set
forth;

       

      WHEREAS,
the Company has filed with the Securities and Exchange Commission (the “SEC”) a
Registration Statement on Form S-1, No. 333-171196 (“Registration Statement”),
for the registration, under the Securities Act of 1933, as amended, of, among
other securities, the Warrants and the shares of Common Stock issuable upon
exercise of the Warrants (the “Warrant Shares”); and

      


       

      WHEREAS,
the Company wishes the Warrant Agent to act on behalf of the Company, and the
Warrant Agent is willing so to act, in connection with the issuance, transfer,
exchange and exercise of the Warrants;

       

      NOW,
THEREFORE, in consideration of the premises and the mutual agreements herein set
forth, the parties hereby agree as follows:

       

      Section
1.         Certain
Definitions.    For purposes of this
Agreement, the following terms have the meanings indicated:

       

      (a)          “Affiliate”
has the meaning ascribed to it in Rule 12b-2 under the Securities Exchange Act
of 1934, as amended (the “Exchange Act”).

       

      (b)          “Business
Day” means any day other than a Saturday, Sunday or a day on which the New York
Stock Exchange is authorized or obligated by law or executive order to
close.

       

      (c)          “Close
of Business” on any given date means 5:00 p.m., New York City time, on such
date; provided,
however, that
if such date is not a Business Day it means 5:00 p.m., New York City time, on
the next succeeding Business Day.


      
        
           


        

        
          1

          
            

          

        

        
           


        

      


      (d)          “Current
Market Price”, as of any date, with respect to a share of Common Stock, shall be
deemed to be the average closing price for the ten consecutive trading days
immediately preceding such date on the principal national securities exchange or
Nasdaq system on which the shares of Common Stock are listed or admitted to
trading or, if not listed or admitted to trading on any national securities
exchange or Nasdaq system, the average of the reported bid and asked prices
during such 10 trading day period in the over-the-counter market as furnished by
the Pink Sheets LLC, or, if such firm is not then engaged in the business of
reporting such prices, as furnished by any similar firm then engaged in such
business selected by the Company, or, if there is no such firm, as furnished by
any member of the Financial Industry Regulatory Authority selected by the
Company or, if the shares of Common Stock are not publicly traded, the Current
Market Price shall be determined in good faith by the Board of Directors of the
Company.

       

      (e)          “Effective
Date” means ________, 2011.

       

      (f)          
“Exercise Price” means the Initial Exercise Price as adjusted from time to time
pursuant to Section 10 hereof.

       

      (g)          “Initial
Exercise Price” means $_______ per share of Common Stock.

       

      (h)          “Person”
means an individual, corporation, association, partnership, limited liability
company, joint venture, trust, unincorporated organization, government or
political subdivision thereof or governmental agency or other
entity.

       

      (i)          
“Warrant Certificate” means a certificate in substantially the form attached as
Exhibit 1 hereto representing such number of Warrants as is indicated on the
face thereof.

       

      Section
2.         Appointment of Warrant
Agent.   The Company
hereby appoints the Warrant Agent to act as agent for the Company in accordance
with the terms and conditions hereof, and the Warrant Agent hereby accepts such
appointment.  The Company may from time to time appoint such
Co-Warrant Agents as it may, in its sole discretion, deem necessary or
desirable.  In no event will the Warrant Agent be liable for the acts
or omissions of any such Co-Warrant Agent.

       

      Section
3.         Form of Warrant
Certificates.   The
Warrant Certificates (together with the form of election to purchase Common
Stock (the “Exercise Notice”) and the form of assignment to be printed on the
reverse thereof) shall be substantially in the form of Exhibit 1 hereto and
may have such marks of identification or designation and such legends, summaries
or endorsements printed thereon as the Company may deem appropriate and as are
not inconsistent with the provisions of this Agreement or as may be required to
comply with any law or with any rule or regulation made pursuant thereto, or to
conform to usage.


      
        
           


        

        
          2

          
            

          

        

        
           


        

      


      Section
4.         Countersignature and
Registration.   The
Warrant Certificates shall be executed on behalf of the Company by its Chairman,
its President or a Vice President, either manually or by facsimile signature,
and have affixed thereto the Company’s seal or a facsimile thereof which shall
be attested by the Secretary or an Assistant Secretary of the Company, either
manually or by facsimile signature.  The Warrant Certificates shall be
countersigned by the Warrant Agent either manually or by facsimile signature and
shall not be valid for any purpose unless so countersigned.  In case
any officer of the Company who shall have signed any of the Warrant Certificates
shall cease to be such officer of the Company before countersignature by the
Warrant Agent and issuance and delivery by the Company, such Warrant
Certificates, nevertheless, may be countersigned by the Warrant Agent, issued
and delivered with the same force and effect as though the person who signed
such Warrant Certificate had not ceased to be such officer of the Company; and
any Warrant Certificate may be signed on behalf of the Company by any person
who, at the actual date of the execution of such Warrant Certificate, shall be a
proper officer of the Company to sign such Warrant Certificate, although at the
date of the execution of this Warrant Agreement any such person was not such an
officer.

       

      The
Warrant Agent will keep or cause to be kept, at one of its offices in Canton,
Massachusetts, or at the office of one of its agents, books for registration and
transfer of the Warrant Certificates issued hereunder.  Such books
shall show the names and addresses of the respective holders of the Warrant
Certificates, the number of warrants evidenced on the face of each of such
Warrant Certificate and the date of each of such Warrant
Certificate.

       

      The
Warrant Agent will create a special account for the issuance of Warrants and the
Warrant Shares.  The Company shall provide an opinion of counsel dated
as of the Effective Date to set up reserve of Warrants and reserve of shares of
Common Stock for issuance upon exercise of the Warrants, upon which opinion the
recipients of the Warrants and Warrant Shares shall be entitled to
rely.  The opinion shall state that:

       

      (1)           The
Warrants and Warrant Shares are registered under the Securities Act of 1933, as
amended;

       

      (2)           The
Warrants, when issued in accordance with the terms of the Warrant
Agreement, will be valid and binding obligations of the Company, enforceable
against the Company in accordance with their terms and are free and clear of all
liens and encumbrances; and

       

       (3)           Upon
the valid exercise in accordance with the terms of the Warrants and payment of
the consideration required in connection therewith, the Warrant Shares will be
validly issued, fully paid and non-assessable, free and clear of all liens and
encumbrances.

       

      Section
5.         Transfer, Split Up,
Combination and Exchange of Warrant Certificates; Mutilated, Destroyed, Lost or
Stolen Warrant Certificates.   Subject to the provisions of
Section 13 hereof and the last sentence of this first paragraph of
Section 5 and subject to applicable law, rules or regulations, restrictions
on transferability that may appear on Warrant Certificates in accordance with
the terms hereof or any “stop transfer” instructions the Company may give to the
Warrant Agent, at any time after the Close of Business on the date hereof, at or
prior to the Close of Business on the Expiration Date (as such term is
hereinafter defined), any Warrant Certificate or Warrant Certificates may be
transferred, split up, combined or exchanged for another Warrant Certificate or
Warrant Certificates, entitling the registered holder to purchase a like number
of shares of Common Stock as the Warrant Certificate or Warrant Certificates
surrendered then entitled such holder to purchase.  Any registered
holder desiring to transfer, split up, combine or exchange any Warrant
Certificate shall make such request in writing delivered to the Warrant Agent,
and shall surrender the Warrant Certificate or Warrant Certificates to be
transferred, split up, combined or exchanged at the principal office of the
Warrant Agent.  Thereupon the Warrant Agent shall, subject to the last
sentence of this first paragraph of Section 5, countersign and deliver to
the person entitled thereto a Warrant Certificate or Warrant Certificates, as
the case may be, as so requested.  The Company may require payment of
a sum sufficient to cover any tax or governmental charge that may be imposed in
connection with any transfer, split up, combination or exchange of Warrant
Certificates, together with reimbursement to the Company and the Warrant Agent
of all reasonable expenses incidental thereto.


      
        
           


        

        
          3

          
            

          

        

        
           


        

      


      Upon
receipt by the Company and the Warrant Agent of evidence reasonably satisfactory
to them of the loss, theft, destruction or mutilation of a Warrant Certificate,
and, in case of loss, theft or destruction, of indemnity or security in
customary form and amount which shall include a corporate bond of indemnity
satisfactory to the Warrant Agent, and reimbursement to the Company and the
Warrant Agent of all reasonable expenses incidental thereto, and upon surrender
to the Warrant Agent and cancellation of the Warrant Certificate if mutilated,
the Company will make and deliver a new Warrant Certificate of like tenor to the
Warrant Agent for delivery to the registered holder in lieu of the Warrant
Certificate so lost, stolen, destroyed or mutilated.

       

      Section
6.     Exercise of Warrants;
Exercise Price; Expiration Date

       

      (a)          The
Warrants shall be exercisable in whole or in part immediately upon and after
issuance.  The Warrants shall cease to be exercisable and shall
terminate and become void, and all rights thereunder and under this Agreement
shall cease, at the Close of Business on the date which is the five year
anniversary of the Effective Date (the “Expiration Date”).  Subject to
the foregoing and to Section 6(b) below, the registered holder of any
Warrant Certificate may exercise the Warrants evidenced thereby in whole or in
part upon surrender of the Warrant Certificate, with the Exercise Notice duly
executed, to the Warrant Agent, or Computershare, as applicable, at the
principal office of the Warrant Agent in Canton, Massachusetts or to the office
of one of its agents as may be designated by the Warrant Agent from time to
time, together with payment of the Exercise Price, which may be made, at the
option of the holder, (i) in cash in United States dollars or by certified or
official bank check, (ii) in the event that the Current Market Price exceeds the
Exercise Price, by a Cashless Exercise (as defined below) or (iii) by any
combination of (i) and (ii), to the principal office of the Warrant Agent where
the Warrant Certificate is being surrendered.  A "Cashless Exercise"
shall mean an exercise of a Warrant in accordance with the immediately following
two sentences.  To effect a Cashless Exercise, the holder may exercise
a Warrant or Warrants without payment of the Exercise Price in cash by
surrendering such Warrant or Warrants (represented by one or more Warrant
Certificates) and, in exchange therefor, receiving such number of shares of
Common Stock equal to the product of (1) that number of shares of Common Stock
for which such Warrants are exercisable and which would be issuable in the event
of an exercise with payment in cash of the Exercise Price and (2) the Cashless
Exercise Ratio (as defined below).  The "Cashless Exercise Ratio"
shall equal a fraction, the numerator of which is the excess of the Current
Market Price (calculated as set forth in this agreement) per share of Common
Stock on the date of exercise over the Exercise Price per share of Common Stock
as of the date of exercise and the denominator of which is the Current Market
Price per share of Common Stock on the date of exercise.  Upon
surrender of a Warrant Certificate representing more than one Warrant in
connection with a holder's option to elect a Cashless Exercise, such holder must
specify the number of Warrants for which such Warrant Certificate is to be
exercised (without giving effect to such Cashless Exercise).  All
provisions of this Agreement shall be applicable with respect to a Cashless
Exercise of a Warrant Certificate of less than the full number of Warrants
represented thereby.  No payment or adjustment shall be made on
account of any distributions or dividends on the Common Stock issued upon
exercise of a Warrant.


      
        
           


        

        
          4

          
            

          

        

        
           


        

      


      The
Company shall calculate and transmit to the Warrant Agent, and the Warrant Agent
shall have no obligation under this section to calculate, the Cashless Exercise
Ratio (and the basis for such calculation (which the Warrant Agent shall have no
obligation under this section to recalculate)).

       

      (b)          Upon
receipt of a Warrant Certificate at or prior to the Close of Business on the
Expiration Date, with the form of election to purchase duly executed,
accompanied by payment of the Exercise Price for the shares to be purchased (or
election of the Cashless Exercise option) and an amount equal to any applicable
tax or governmental charge referred to in Section 5 in cash, or by
certified check or bank draft payable to the order of the Company, the Warrant
Agent shall thereupon promptly (i) requisition from any transfer agent of
the Common Stock certificates for the number of whole shares of Common Stock to
be purchased, and the Company hereby irrevocably authorizes its transfer agent
to comply with all such requests and (ii)  after receipt of such
certificates, use its best efforts to cause the same to be delivered to or upon
the order of the registered holder of such Warrant Certificate, registered in
such name or names as may be designated by such holder, within three (3) trading
days following exercise of such Warrants (the “Delivery Date”).  Upon
receipt by the Company of a Warrant Certificate at the principal office of the
Warrant Agent, with the form of election to purchase duly executed, and payment
of the applicable Exercise Price as required hereby, the holder of such Warrant
Certificate shall be deemed to be the holder of record of the shares of Common
Stock issuable upon such exercise, notwithstanding that the stock transfer books
of the Company shall then be closed or that certificates representing such
shares of Common Stock shall not then be actually delivered to the holder of
such Warrant Certificate.

       

      (c)          In
case the registered holder of any Warrant Certificate shall exercise fewer than
all Warrants evidenced thereby, a new Warrant Certificate evidencing the number
of Warrants equivalent to the number of Warrants remaining unexercised shall be
issued by the Warrant Agent to the registered holder of such Warrant Certificate
or to his duly authorized assigns, subject to the provisions of Sections 5,
6(b) and 13 hereof.

       

      (d)          In
addition to a holder’s other available remedies, the Company shall pay to such a
holder, in cash, as liquidated damages and not as a penalty, for non-delivery by
the Delivery Date, an amount equal to the difference between the closing price
of the Common Stock on the Delivery Date and the closing price of the Common
Stock on the date the Common Stock is actually delivered multiplied by the
number of Warrant Shares so exercised.


      
        
           


        

        
          5

          
            

          

        

        
           


        

      


      (e)          The registered holder shall not have the right to
exercise any portion of such
holder’s Warrants, pursuant to Section 6 or otherwise, to the extent that after giving effect
to such issuance after exercise as set forth on the applicable Exercise Notice
duly executed, such holder (together with such holder’s Affiliates,
and
any other person or entity acting as a group together with such holder or any of
such holder’s Affiliates), would beneficially own in excess of the
Beneficial Ownership Limitation (as defined below).  For purposes of
the foregoing sentence, the number of shares of
Common Stock beneficially owned by such holder and its Affiliates shall include
the number of shares of Common Stock issuable upon exercise of such
holder’s Warrants with respect to which such determination is
being made, but shall exclude the number of shares of
Common Stock which would be issuable upon (A) exercise of the remaining,
nonexercised portion of such holder’s Warrants
beneficially owned by such holder or any of its Affiliates and (B) exercise or
conversion of the unexercised or nonconverted portion of
any other securities of the Company (including, without limitation, any other
Common Stock equivalents) subject to a limitation on conversion or exercise
analogous to the limitation contained herein beneficially owned by such holder
or any
of its Affiliates.  Except as set forth in the preceding sentence, for
purposes of this Section 6(e), beneficial ownership shall be calculated in
accordance with Section 13(d) of the Exchange Act and the rules and regulations
promulgated thereunder, it being acknowledged by such holder that the Company is not
representing to such holder that such calculation is in compliance with Section
13(d) of the Exchange Act and such holder is solely responsible for any
schedules required to be filed in accordance therewith.   To the extent that the
limitation contained in this Section 6(e) applies, the determination of whether
such holder’s Warrants are exercisable (in relation to other
securities owned by such holder together with any Affiliates) and of which
portion of such holder’s Warrants are
exercisable shall be in the sole discretion of such holder, and the submission
of an Exercise Notice shall be deemed to be such holder’s determination of
whether its Warrants are exercisable (in relation to other
securities owned by such holder together with any Affiliates) and
of which portion of such holder’s Warrants are
exercisable, in each case subject to the Beneficial Ownership Limitation, and
the Company shall have no obligation to verify or confirm the accuracy of
such
determination or any liability under this Section 6(e).  In
addition, a determination as to any group status as contemplated above shall be
determined in the sole discretion of such holder in accordance with Section
13(d) of the Exchange Act and the rules and regulations
promulgated thereunder, and the acquisition by any or all holders of the Common
Stock and the Warrants and the execution of this Agreement shall not, by itself,
cause any such holders to be considered a group for purposes of the
Exchange Act.  For purposes of determining the
Beneficial Ownership Limitation, in determining the number of outstanding shares
of Common Stock, a holder may rely on the number of outstanding shares of Common
Stock as reflected in (x) the Company’s most recent
Annual
Report on Form 10-K or Quarterly Report on Form 10-Q, or such similar form, as
the case may be, or (y) any other written notice by the Company or the
Company’s transfer agent setting forth the number of shares of
Common Stock outstanding.  In any case, the number of
outstanding shares of Common Stock shall be determined after giving effect to
the conversion or exercise of securities of the Company, including such
holder’s Warrants, by such holder or its Affiliates since the
date as of which such number of
outstanding shares of Common Stock was reported.  The “Beneficial Ownership Limitation” shall be 9.999% of the number of shares of the Common
Stock outstanding immediately after giving effect to the issuance of shares of
Common Stock (net of the effects of any Cashless
Exercise) issuable upon exercise of such holder’s
Warrants.  Subject to the 20% Limitation (as defined below), the
Beneficial Ownership Limitation provisions of this Section 6(e) may be waived by
such holder, at the election of such holder, upon not less
than sixty-one (61) days’ prior notice to the Company to waive the Beneficial
Ownership Limitation.  So long as the Beneficial Ownership Limitation
has not been waived by such holder, the shares of Common Stock underlying such
holder’s Warrants in excess of the Beneficial Ownership Limitation
shall not be deemed to be beneficially owned by such holder for purposes of
Section 16 of the Exchange Act.  Notwithstanding anything contained
herein to the contrary, in no event may a holder have the right to
exercise such holder’s Warrants (or otherwise have the right to acquire
capital stock of the Company as a result of holding Warrants or Warrant Shares)
to the extent (and only to the extent) that, following such exercise or
acquisition, such holder would own or beneficially own 20% or more of the
outstanding shares of Common Stock or would otherwise cause such holder to be an
“Acquiring Person” (as defined under that certain Rights Agreement dated
September 1, 1999, as amended through the date hereof (the
“Rights Agreement”), by and between the Company and Computershare
Trust Company, N.A.) after giving effect to such
exercise or acquisition (the “20%
Limitation”), and any such exercise or
acquisition in excess of the 20% Limitation or attempt to so exercise or acquire shall be void ab initio.  Each holder of Warrants covenants that such
holder will not exercise such holder’s Warrant in
violation of the 20% Limitation and, in the event any holder violates such
covenant by so exercising or attempting to
so exercise its Warrants, such holder shall indemnify and hold the Company
harmless from and against any and all losses, damages, costs, charges, counsel
fees, payments, expenses and liability arising out of such violation of such
covenant.  The limitations contained in
this paragraph shall apply to a successor holder of Warrant
Certificates.


      
        
           


        

        
          6

          
            

          

        

        
           


        

      


      


      (f)          On
any Mandatory Exercise Date (as defined below), subject to Section 6(e) hereof
(including the 20% Limitation), the Company may, at its option and upon at least
sixty (60) days prior written notice to any registered holder of Warrants, elect
to require such holder to exercise its Warrants, in whole or in part, by
surrendering its Warrant Certificate, with the Exercise Notice duly executed by
or on behalf of such holder, to the Warrant Agent at the principal office of the
Warrant Agent in Canton, Massachusetts or to the office of one of its agents as
may be designated by the Warrant Agent from time to time, together with payment
of the Exercise Price payable in respect of the number of shares of Common Stock
purchased upon such exercise and/or the holder’s exercise of its Cashless
Exercise rights, in whole or in part.  In the event that a registered
holder is restricted from exercising such Warrants pursuant to Section
6(e), such holder shall use its commercially reasonable efforts to sell shares
of Common Stock held by such holder to the extent necessary to exercise the
number of Warrants as elected by the Company without restriction under Section
6(e).  The “Mandatory Exercise Date” means a date, any time after the
Effective Date, on which the last closing sales price of the Common Stock is at
least $_______ per share (as adjusted for stock splits, stock dividends, stock
combinations or similar transactions) for at least twenty (20) trading days over
a consecutive thirty (30) day trading period.

       

      Section
7.         Cancellation and Destruction
of Warrant Certificates.  
All Warrant Certificates surrendered for the purpose of exercise, transfer,
split up, combination or exchange shall, if surrendered to the Company or to any
of its agents, be delivered to the Warrant Agent for cancellation or in canceled
form, or, if surrendered to the Warrant Agent, shall be canceled by it, and no
Warrant Certificates shall be issued in lieu thereof except as expressly
permitted by any of the provisions of this Warrant Agreement.  The
Company shall deliver to the Warrant Agent for cancellation and retirement, and
the Warrant Agent shall so cancel and retire, any other Warrant Certificate
purchased or acquired by the Company otherwise than upon the exercise
thereof.  The Warrant Agent shall deliver all canceled Warrant
Certificates to the Company, or shall, at the written request of the Company,
destroy such canceled Warrant Certificates, and in such case shall deliver a
certificate of destruction thereof to the Company, subject to any applicable
law, rule or regulation requiring the Warrant Agent to retain such canceled
certificates.


      
        
           


        

        
          7

          
            

          

        

        
           


        

      


      Section
8.         Certain Representations;
Reservation and Availability of Shares of Common Stock or
Cash.

       

      (a)          The
Company represents and warrants that this Agreement has been duly authorized,
executed and delivered by the Company and, assuming due authorization, execution
and delivery hereof by the Warrant Agent, constitutes a valid and legally
binding obligation of the Company enforceable against the Company in accordance
with its terms, and the Warrants and, when issued, the Warrant Shares, in each
case, are free and clear of all liens and encumbrances, are fully paid and
non-assessable and have been duly authorized, executed and issued by the Company
and, assuming due authentication of the Warrants by the Warrant Agent pursuant
hereto, constitute valid and legally binding obligations of the Company
enforceable against the Company in accordance with their terms and entitled to
the benefits hereof; in each case except as enforceability may be limited by
bankruptcy, insolvency, reorganization, moratorium and other similar laws
relating to or affecting creditors’ rights generally or by general equitable
principles (regardless of whether such enforceability is considered in a
proceeding in equity or at law).

       

      (b)          The
Company represents and warrants that, immediately prior to the consummation of
the offering described in the Registration Statement, the authorized capital
stock of the Company consists of (i) 75,000,000 shares of Common Stock, of which
9,216,209 shares of Common Stock are issued and outstanding, 2,070,000 shares of
Common Stock are reserved for issuance upon exercise of the Series A Warrants,
1,690,500 shares of Common Stock upon exercise of Series B Warrants and not more
than 827,004 shares of Common Stock are reserved for issuance upon exercise of
employee or other stock options and (ii) 5,000,000 shares of preferred stock,
$.001 par value per share, of which no shares are
outstanding.   The Company represents and warrants that the
shares of Common Stock issued to the holder under the Registration Statement,
when issued, were free and clear of all liens and encumbrances, fully paid and
non-assessable and were duly authorized by the Company.

       

      (c)          The
Company covenants and agrees that it will cause to be reserved and kept
available out of its authorized and unissued shares of Common Stock or its
authorized and issued shares of Common Stock held in its treasury, free from
preemptive rights, the number of shares of Common Stock that will be sufficient
to permit the exercise in full of all outstanding Warrants and all other
convertible securities, options and other instruments of the
Company.

      


      (d)          The
Company further covenants and agrees that it will pay when due and payable any
and all federal and state transfer taxes and charges which may be payable in
respect of the original issuance or delivery of the Warrant Certificates or
certificates evidencing Common Stock upon exercise of the
Warrants.  The Company shall not, however, be required to pay any tax
or governmental charge which may be payable in respect of any transfer involved
in the transfer or delivery of Warrant Certificates or the issuance or delivery
of certificates for Common Stock in a name other than that of the registered
holder of the Warrant Certificate evidencing Warrants surrendered for exercise
or to issue or deliver any such certificate for such shares of Common Stock to
such other person upon the exercise of any Warrants until any such tax or
governmental charge shall have been paid (any such tax or governmental charge
being payable by the holder of such Warrant Certificate at the time of
surrender) or until it has been established to the Company’s reasonable
satisfaction that no such tax or governmental charge is due.


      
        
           


        

        
          8

          
            

          

        

        
           


        

      


      (e)          The
Company acknowledges that the bank accounts maintained by Computershare in
connection with the services provided under this Agreement will be in its name
and that Computershare may receive investment earnings in connection with the
investment at Computershare risk and for its benefit of the funds held in those
accounts from time to time.  Neither the Company nor the Holders will
receive interest on any deposits or Exercise Price payments.

       

      (f)          For
purposes of determining whether a holder is an “Acquiring Person” under the
Rights Agreement, the Company acknowledges, and the Company represents and
warrants that it has taken all necessary action, if any, to ensure, that, as a
result of the provisions of Section 6(e), holders shall not be deemed the
“Beneficial Owner” (as defined in the Rights Agreement) of such holder’s
Warrants (and shares of Common Stock issuable upon exercise thereof) to the
extent that such Warrants (and shares of Common Stock issuable upon exercise
thereof) would exceed the 20% Limitation.  The Company represents and
warrants that the Board of Directors of the Company has taken all necessary
action in order to ensure that, notwithstanding any holder becoming an
“interested person” under Delaware General Corporation Law Section 203 or other
similar anti-takeover provision under the Company’s certificate of incorporation
(or similar charter documents) or the laws of its state of incorporation that is
or could become applicable to the holders as a result of the execution and
delivery of this Agreement, such holder shall not be prohibited from exercising such holder’s Warrants (or
otherwise having the right to acquire
capital stock of the Company as a result of holding Warrants or Warrant
Shares), except to the extent that exercising such Warrants or otherwise
acquiring capital stock of the Company as a result of holding Warrants or
Warrant Shares would cause such holder to exceed the 20%
Limitation.

       

      Section
9.         Common Stock Record
Date.   Each person in
whose name any certificate for shares of Common Stock is issued upon the
exercise of Warrants shall for all purposes be deemed to have become the holder
of record for the Common Stock represented thereby on, and such certificate
shall be dated, the date upon which the Warrant Certificate evidencing such
Warrants was duly surrendered and payment of the Exercise Price (and any
applicable transfer taxes) was made; provided, however, that,
subject to Section 6(b) of this Agreement, if the date of such surrender and
payment is a date upon which the Common Stock transfer books of the Company are
closed, such person shall be deemed to have become the record holder of such
shares on, and such certificate shall be dated, the next succeeding day on which
the Common Stock transfer books of the Company are open.


      
        
           


        

        
          9

          
            

          

        

        
           


        

      


       
Section 10.         Adjustment of Exercise
Price, Number of Shares of Common Stock or Number of the Company
Warrants.   The Exercise
Price, the number of shares covered by each Warrant and the number of Warrants
outstanding are subject to adjustment from time to time as provided in this
Section 10.

       

      (a)          In
the event the Company shall at any time after the date of this Agreement
(i) declare a dividend on shares of Common Stock payable in shares of any
class of capital stock of the Company, (ii) subdivide the outstanding
shares of Common Stock into a greater number of shares of Common Stock,
(iii) combine the outstanding shares of Common Stock into a smaller number
of shares, or (iv) issue any shares of capital stock in a reclassification
of shares of the Common Stock (including any such reclassification in connection
with a consolidation or merger in which the Company is the continuing
corporation), the Exercise Price in effect at the time of the record date for
such dividend or distribution or of the effective date of such subdivision,
combination or reclassification, and the number and kind of shares of capital
stock issuable on such date, shall be proportionately adjusted so that the
holder of any Warrant exercised after such time shall be entitled to receive the
aggregate number and kind of shares of capital stock which, if such Warrant had
been exercised immediately prior to such date and at a time when the Common
Stock transfer books of the Company were open, such holder would have owned upon
such exercise and been entitled to receive by virtue of such dividend,
subdivision, combination or reclassification.

       

      (b)          In
the event the Company shall fix a record date for the issuance of rights,
options or warrants to all holders of Common Stock (such rights, options or
warrants not being available to holders of Warrants) entitling them (for a
period expiring within 45 calendar days after such date of issue) to subscribe
for or purchase Common Stock (or securities convertible into or exercisable or
exchangeable for Common Stock), at a price per share of Common Stock (or having
a conversion, exercise or exchange price per share of Common Stock, in the case
of a security convertible into or exercisable or exchangeable for Common Stock)
less than the Current Market Price per share of Common Stock on such record date
(or, if there has been no such determination, then the Company must promptly
cause such determination to be made as contemplated by the definition of
“Current Market Price” set forth herein, and any proposed record date must be
postponed until after such determination has been made), the Exercise Price to
be in effect after such record date shall be determined by multiplying the
Exercise Price in effect immediately prior to such record date by a fraction of
which the numerator shall be the number of shares of Common Stock outstanding on
such record date plus the number of shares of Common Stock which the aggregate
offering price of the total number of shares of Common Stock so to be offered
(or the aggregate initial conversion, exercise or exchange price of the
convertible, exercisable or exchangeable securities so to be offered) would
purchase at such Current Market Price and of which the denominator shall be the
number of shares of Common Stock outstanding on such record date plus the number
of additional shares of Common Stock to be offered for subscription or purchase
(or into which the convertible, exercisable or exchangeable securities so to be
offered are initially convertible, exercisable or exchangeable).  In
case such subscription price may be paid in a consideration part or all of which
shall be in a form other than cash, the value of such consideration shall be as
determined in good faith by the Board of Directors of the
Company.  Such adjustment shall be made successively whenever such a
record date is fixed, and in the event that such rights or warrants are not so
issued the Exercise Price shall be adjusted to be the Exercise Price which would
then be in effect if such record date had not been fixed. 


      
        
           


        

        
          10

          
            

          

        

        
           


        

      


      (c)          In
the event the Company shall fix a record date for the making of a dividend or
distribution to all holders of Common Stock of any evidences of indebtedness or
assets or subscription rights or warrants (excluding those referred to in
Section 10(a) or (b) or other dividends paid out of retained earnings), the
Exercise Price to be in effect after such record date shall be determined by
multiplying the Exercise Price in effect immediately prior to such record date
by a fraction of which the numerator shall be the Current Market Price per share
of Common Stock on such record date, less the fair market value (as determined
in good faith by the Board of Directors of the Company) of such distribution
applicable to one share of Common Stock, and of which the denominator shall be
such Current Market Price per share of Common Stock.  Such adjustment
shall be made successively whenever such a record date is fixed, and in the
event that such distribution is not so made, the Exercise Price shall again be
adjusted to be the Exercise Price which would then be in effect if such record
date had not been fixed.

       

      (d)          In
the event the Company shall consummate a tender offer for or otherwise
repurchase or redeem Common Stock, to the extent that the cash and value of any
other consideration included in such payment per share of Common Stock exceeds
the Current Market Price per share of Common Stock on the trading day next
succeeding the Expiration Time (as defined below), unless the Company tenders
for the Warrants on terms which give effect to such excess consideration, the
Exercise Price shall be reduced so that the same shall equal the price
determined by multiplying the Exercise Price in effect immediately prior to the
last time tenders or repurchases or redemptions may be made pursuant to such
tender or repurchase or redemption (the “Expiration Time”) by a fraction of
which the numerator shall be the number of shares of Common Stock outstanding
(including any tendered, repurchased or redeemed shares) at the Expiration Time
multiplied by the Current Market Price per share of the Common Stock on the
trading day next succeeding the Expiration Time, and the denominator shall be
the sum of (A) the fair market value of the aggregate consideration payable
to shareholders based on the acceptance of all shares validly tendered,
repurchased or redeemed and not withdrawn as of the Expiration Time (the shares
deemed so accepted being referred to as the “Purchased Shares”) and (B) the
product of the number of shares of Common Stock outstanding (less any Purchased
Shares) at the Expiration Time and the Current Market Price per share of the
Common Stock on the trading day next succeeding the Expiration Time, such
reduction to become effective immediately prior to the opening of business on
the day following the Expiration Time.  For purposes of this
paragraph (d), the value of non cash-consideration shall be as determined
in good faith by the Board of Directors of the Company.

       

      (e)          Notwithstanding
the foregoing paragraphs (a), (b), (c) and (d), no adjustment in the
Exercise Price pursuant to such paragraphs shall be required unless such
adjustment would require an increase or decrease of at least 1% in such price;
provided, however, that any
adjustments which by reason of this Section 10(e) are not required to be
made shall be carried forward and taken into account in any subsequent
adjustment.  All calculations under this Section 10 shall be made
to the nearest cent or the nearest hundredth of a share, as the case may
be.


      
        
           


        

        
          11

          
            

          

        

        
           


        

      


      (f)          In
the event that at any time, as a result of an adjustment made pursuant to
Section 10(a), the holder of any Warrant thereafter exercised shall become
entitled to receive any shares of capital stock of the Company other than shares
of Common Stock, thereafter the number of such other shares so receivable upon
exercise of any Warrant shall be subject to adjustment from time to time in a
manner and on terms as nearly equivalent as practicable to the provisions with
respect to the shares contained in Section 10(a), (b), (c) and (d), and the
provisions of Sections 6, 8, 9 and 12 with respect to the shares of Common
Stock shall apply on like terms to any such other shares.

       

      (g)          All
Warrants originally issued by the Company subsequent to any adjustment made to
the Exercise Price hereunder shall evidence the right to purchase, at the
adjusted Exercise Price, the number of shares of Common Stock purchasable from
time to time hereunder upon exercise of the Warrants, all subject to further
adjustment as provided herein.

       

      (h)          Unless
the Company shall have exercised its election as provided in Section 10(i),
upon each adjustment of the Exercise Price as a result of the calculations made
in Section 10(b), (c) and (d), each Warrant outstanding immediately prior
to the making of such adjustment shall thereafter evidence the right to
purchase, at the adjusted Exercise Price, that number of shares (calculated to
the nearest hundredth) obtained by (i) multiplying (x) the number of
shares covered by a Warrant immediately prior to such adjustment by (y) the
Exercise Price in effect immediately prior to such adjustment of the Exercise
Price and (ii) dividing the product so obtained by the Exercise Price in
effect immediately after such adjustment of the Exercise Price.

       

      (i) The
Company may elect on or after the date of any adjustment of the Exercise Price
to adjust the number of Warrants, in substitution for any adjustment in the
number of shares of Common Stock purchasable upon the exercise of a Warrant.
Each of the Warrants outstanding after such adjustment of the number of Warrants
shall be exercisable for one share of Common Stock. Each Warrant held of record
prior to such adjustment of the number of Warrants shall become that number of
Warrants (calculated to the nearest hundredth) obtained by dividing the Exercise
Price in effect prior to adjustment of the Exercise Price by the Exercise Price
in effect after adjustment of the Exercise Price. The Company shall instruct the
Warrant Agent to notify each of the record holders of Warrants of its election
to adjust the number of Warrants, indicating the record date for the adjustment,
and, if known at the time, the amount of adjustment to be made. Such record date
may be the date on which the Exercise Price is adjusted or any day thereafter,
but shall be at least 10 days later than the date of the public announcement.
Upon each adjustment of the number of Warrants pursuant to this Section 10(i),
the Company shall instruct the Warrant Agent to distribute, as promptly as
practicable, to holders of record of Warrant Certificates on such record date
Warrant Certificates evidencing, subject to Section 13, the additional Warrants
to which such holders shall be entitled as a result of such adjustment, or, at
the option of the Company, instruct the Warrant Agent to distribute to such
holders of record in substitution and replacement for the Warrant Certificates
held by such holders prior to the date of adjustment, and upon surrender
thereof, if required by the Company, new Warrant Certificates evidencing all the
Warrants to which such holders shall be entitled after such adjustment. Warrant
Certificates so to be distributed shall be issued, executed and countersigned in
the manner provided for herein (and may bear, at the option of the Company, the
adjusted Exercise Price) and shall be registered in the names of the holders of
record of Warrant Certificates on the record date specified in the public
announcement.


      
        
           


        

        
          12

          
            

          

        

        
           


        

      


      (j)          Irrespective
of any adjustment or change in the Exercise Price or the number of shares of
Common Stock issuable upon the exercise of the Warrants, the Warrant
Certificates theretofore and thereafter issued may continue to express the
Exercise Price per share and the number of shares which were expressed upon the
initial Warrant Certificates issued hereunder.

       

      (k)          The
Company agrees that it will not, by amendment of its Certificate of
Incorporation or through reorganization, consolidation, merger, dissolution or
sale of assets, or by any other voluntary act, avoid or seek to avoid the
observance or performance of any of the covenants, stipulations or conditions to
be observed or performed hereunder by the Company.  

       

      (l)
          In any case in which
this Section 10 shall require that an adjustment in the Exercise Price be
made effective as of a record date for a specified event, if any holder of a
Warrant exercises such Warrant after such record date, the Company may elect to
defer, until the occurrence of such event, the issuance of the shares of Common
Stock and other capital stock of the Company in excess of the shares of Common
Stock and other capital stock of the Company, if any, issuable upon such
exercise on the basis of the Exercise Price in effect prior to such adjustment;
provided, however, that the
Company shall deliver to such holder a due bill or other appropriate instrument
evidencing such holder’s right to receive such additional shares and/or other
capital securities upon the occurrence of the event requiring such
adjustment.

       

       
Section 11.         Certification of Adjusted
Exercise Price or Number of Shares of Common Stock.   Whenever the Exercise Price or the
number of shares of Common Stock issuable upon the exercise of each Warrant is
adjusted as provided in Section 10 or 12, the Company shall
(a) promptly prepare a certificate setting forth the Exercise Price and
number of shares of Common Stock issuable upon exercise of each Warrant as so
adjusted, and a brief statement of the facts accounting for such adjustment,
(b) promptly file with the Warrant Agent and with each transfer agent for
the Common Stock a copy of such certificate and (c) instruct the Warrant
Agent to mail a brief summary thereof to each holder of a Warrant
Certificate.

       

       
Section 12.         Reclassification,
Consolidation, Purchase, Combination, Sale or Conveyance.   In case any of the following shall
occur while any Warrants are outstanding: (i)  any reclassification of the
Common Stock or any compulsory share exchange pursuant to which the Common Stock
is effectively converted into or exchanged for other securities, cash or
property, or (ii) any consolidation, merger or combination of the Company
with or into another corporation as a result of which holders of Common Stock
shall be entitled to receive stock, securities or other property or assets
(including cash) with respect to or in exchange for such Common Stock, or
(iii) any sale or conveyance of the property or assets of the Company as,
or substantially as, an entirety to any other entity as a result of which
holders of Common Stock shall be entitled to receive stock, securities or other
property or assets (including cash) with respect to or in exchange for such
Common Stock, then the Company, or such successor corporation or transferee, as
the case may be, shall make appropriate provision by amendment of this Agreement
or by the successor corporation or transferee executing with the Warrant Agent
an agreement so that the holders of the Warrants then outstanding shall have the
right at any time thereafter, upon exercise of such Warrants (in lieu of the
number of shares of Common Stock theretofore deliverable) to receive the kind
and amount of securities, cash and other property receivable upon such
reclassification, change, consolidation, merger, combination, sale or conveyance
as would be received by a holder of the number of shares of Common Stock
issuable upon exercise of such Warrant immediately prior to such
reclassification, change, consolidation, merger, sale or
conveyance.


      
        
           


        

        
          13

          
            

          

        

        
           


        

      


      If the
holders of the Common Stock may elect from choices the kind or amount of
securities or cash receivable upon such reclassification, change, consolidation,
merger, combination, sale or conveyance, then for the purpose of this
Section 12 the kind and amount of securities or cash receivable upon such
reclassification, change, consolidation, merger, combination, sale or conveyance
shall be deemed to be the choice specified by the holder of the Warrant, which
specification shall be made by the holder of the Warrant by the later of
(A) 20 calendar days after the holder of the Warrant is provided with a
final version of all information required by law or regulation to be furnished
to holders of Common Stock concerning such choice, or if no
such  information is required, 20 days after the Company notified the
holder of the Warrant of all material facts concerning such specification and
(B) the last time at which holders of Common Stock are permitted to make
their specification known to the Company.  If the holder of the
Warrant fails to make any specification, the holder’s choice shall be deemed to
be whatever choice is made by a plurality of holders of Common Stock not
affiliated with the Company or any other party to the reclassification, change,
consolidation, merger, combination, sale or conveyance.  Such adjusted
Warrants shall provide for adjustments which, for events subsequent to the
effective date of such new Warrants, shall be as nearly equivalent as may be
practicable to the adjustments provided for in Section 10 and this
Section 12.  The above provisions of this Section 12 shall
similarly apply to successive reclassifications, changes, consolidations,
mergers, combinations, sales and conveyances of the kind described
above.

       

      The
Company shall instruct the Warrant Agent to mail by first class mail, postage
prepaid, to each registered holder of a Warrant, written notice of the execution
of any such amendment, supplement or agreement.  Any supplemented or
amended agreement entered into by the successor corporation or transferee shall
provide for adjustments, which shall be as nearly equivalent as may be
practicable to the adjustments provided for in Section 10 and this Section
12.  The Warrant Agent shall be under no responsibility to determine
the correctness of any provisions contained in such agreement relating either to
the kind or amount of securities or other property receivable upon exercise of
warrants or with respect to the method employed and provided therein for any
adjustments and shall be entitled to rely upon the provisions contained in any
such agreement.  The provisions of this Section 12 shall
similarly apply to successive reclassifications, changes, consolidations,
mergers, sales and conveyances of the kind described above.

       

       
Section 13.         Fractional Shares of Common
Stock.

       

      (a)          The
Company shall not issue fractions of Warrants or distribute Warrant Certificates
which evidence fractional Warrants.  Whenever any fractional Warrant
would otherwise be required to be issued or distributed, the actual issuance or
distribution shall reflect a rounding of such fraction down to the nearest whole
Warrant.


      
        
           


        

        
          14

          
            

          

        

        
           


        

      


      (b)          The
Company shall not issue fractions of shares of Common Stock upon exercise of
Warrants or distribute stock certificates which evidence fractional shares of
Common Stock.  Whenever any fraction of a share of Common Stock would
otherwise be required to be issued or distributed, the actual issuance or
distribution made shall reflect a rounding of such fraction down to the nearest
whole share.

       

      (c)          The
holder of a Warrant by the acceptance of the Warrant expressly waives his right
to receive any fractional Warrant or any fractional share of Common Stock upon
exercise of a Warrant.

        

       
Section 14.         Agreement of Warrant
Certificate Holders.  
Every holder of a Warrant Certificate by accepting the same consents and agrees
with the Company and the Warrant Agent and with every other holder of a Warrant
Certificate that:

       

      (a)          the
Warrant Certificates are transferable only on the registry books of the Warrant
Agent if surrendered at the principal office of the Warrant Agent, duly endorsed
or accompanied by a proper instrument of transfer and any reasonable evidence of
authority that may be required by the Warrant Agent. Such evidence shall include
a signature guarantee from an eligible guarantor institution participating in a
signature guarantee program approved by the Securities Transfer Association;
and

       

      (b)          the
Company and the Warrant Agent may deem and treat the person in whose name the
Warrant Certificate is registered as the absolute owner thereof and of the
Warrants evidenced thereby (notwithstanding any notations of ownership or
writing on the Warrant Certificates made by anyone other than the Company or the
Warrant Agent) for all purposes whatsoever, and neither the Company nor the
Warrant Agent shall be affected by any notice to the contrary.

       

       
Section 15.         Warrant Certificate Holder
Not Deemed a Shareholder.   No holder, as such, of any Warrant
Certificate shall be entitled to vote, receive dividends or distributions on, or
be deemed for any purpose the holder of Common Stock or any other securities of
the Company which may at any time be issuable on the exercise of the Warrants
represented thereby, nor shall anything contained herein or in any Warrant
Certificate be construed to confer upon the holder of any Warrant Certificate,
as such, any of the rights of a shareholder of the Company or any right to vote
for the election of directors or upon any matter submitted to shareholders at
any meeting thereof, or to give or withhold consent to any corporate action, or
to receive notice of meetings or other actions affecting shareholders, or to
receive dividends or distributions or subscription rights, or otherwise, until
the Warrant or Warrants evidenced by such Warrant Certificate shall have been
exercised in accordance with the provisions hereof

       

       
Section 16.         Concerning the Warrant
Agent.

       

      (a)          The
Company agrees to pay to the Warrant Agent reasonable compensation for all
services rendered by it hereunder and, from time to time, on demand of the
Warrant Agent, its reasonable expenses and counsel fees and other disbursements
incurred in the administration and execution of this Agreement and the exercise
and performance of its duties hereunder.


      
        
           


        

        
          15

          
            

          

        

        
           


        

      


      (b)          The
Company covenants and agrees to indemnify and to hold the Warrant Agent harmless
against any costs, expenses (including reasonable fees of its legal counsel),
losses or damages, which may be paid, incurred or suffered by or to which it may
become subject, arising from or out of, directly or indirectly, any claims or
liability resulting from its actions as Warrant Agent pursuant hereto; provided,
that such covenant and agreement does not extend to, and the Warrant Agent shall
not be indemnified with respect to, such costs, expenses, losses and damages
incurred or suffered by the Warrant Agent as a result of, or arising out of, its
gross negligence, bad faith, or willful misconduct.

       

      (c)          Promptly
after the receipt by the Warrant Agent of notice of any demand or claim or the
commencement of any action, suit, proceeding or investigation, the Warrant Agent
shall, if a claim in respect thereof is to be made against the Company, notify
the Company thereof in writing.   The Company shall be entitled
to participate at its own expense in the defense of any such claim or
proceeding, and, if it so elects at any time after receipt of such notice, it
may assume the defense of any suit brought to enforce any such claim or of any
other legal action or proceeding. For the purposes of this Section 16, the term
“expense or loss” means any amount paid or payable to satisfy any claim, demand,
action, suit or proceeding settled with the express written consent of the
Warrant Agent, and all reasonable costs and expenses, including, but not limited
to, reasonable counsel fees and disbursements, paid or incurred in investigating
or defending against any such claim, demand, action, suit, proceeding or
investigation.

       

      (d)          The
Warrant Agent shall be responsible for and shall indemnify and hold the Company
harmless from and against any and all losses, damages, costs, charges, counsel
fees, payments, expenses and liability arising out of or attributable to the
Warrant Agent’s refusal or failure to comply with the terms of this Agreement,
or which arise out of Warrant Agent’s negligence or willful misconduct or which
arise out of the breach of any representation or warranty of the Warrant Agent
hereunder, for which the Warrant Agent is not entitled to indemnification under
this Agreement; provided, however, that Warrant Agent’s aggregate liability
during any term of this Agreement with respect to, arising from, or arising in
connection  with  this  Agreement, or from all
services provided or omitted to be provided under this Agreement, whether in
contract, or in tort, or otherwise, is limited to, and shall not exceed, the
amounts paid under this Agreement by the Company to Warrant Agent as fees and
charges, but not including reimbursable expenses.

       

      (e)          Promptly
after the receipt by the Company of notice of any demand or claim or the
commencement of any action, suit, proceeding or investigation, the Company
shall, if a claim in respect thereof is to be made against the Warrant Agent,
notify the Warrant Agent thereof in writing.  The Warrant Agent shall
be entitled to participate at its own expense in the defense of any such claim
or proceeding, and, if it so elects at any time after receipt of such notice, it
may assume the defense of any suit brought to enforce any such claim or of any
other legal action or proceeding.  For the purposes of this Section
16, the term “expense or loss” means any amount paid or payable to satisfy any
claim, demand, action, suit or proceeding settled with the express written
consent of the Company, and all reasonable costs and expenses, including, but
not limited to, reasonable counsel fees and disbursements, paid or incurred in
investigating or defending against any such claim, demand, action, suit,
proceeding or investigation.


      
        
           


        

        
          16

          
            

          

        

        
           


        

      


      (f)          Neither
party to this Agreement shall be liable to the other party for any
consequential, indirect, special or incidental damages under any provision of
this Agreement or for any consequential, indirect, penal, special or incidental
damages arising out of any act or failure to act hereunder even if that party
has been advised of or has foreseen the possibility of such
damages.

      


       
Section 17.         Purchase or Consolidation or
Change of Name of Warrant Agent.   Any corporation into which the
Warrant Agent or any successor Warrant Agent may be merged or with which it may
be consolidated, or any corporation resulting from any merger or consolidation
to which the Warrant Agent or any successor Warrant Agent shall be party, or any
corporation succeeding to the corporate trust business of the Warrant Agent or
any successor Warrant Agent, shall be the successor to the Warrant Agent under
this Agreement without the execution or filing of any paper or any further act
on the part of any of the parties hereto, provided that such corporation would
be eligible for appointment as a successor Warrant Agent under the provisions of
Section 19.  In case at the time such successor Warrant Agent
shall succeed to the agency created by this Agreement any of the Warrant
Certificates shall have been countersigned but not delivered, any such successor
Warrant Agent may adopt the countersignature of the predecessor Warrant Agent
and deliver such Warrant Certificates so countersigned; and in case at that time
any of the Warrant Certificates shall not have been countersigned, any successor
Warrant Agent may countersign such Warrant Certificates either in the name of
the predecessor Warrant Agent or in the name of the successor Warrant Agent; and
in all such cases such Warrant Certificates shall have the full force provided
in the Warrant Certificates and in this Agreement.

       

      In case
at any time the name of the Warrant Agent shall be changed and at such time any
of the Warrant Certificates shall have been countersigned but not delivered, the
Warrant Agent may adopt the countersignature under its prior name and deliver
Warrant Certificates so countersigned; and in case at that time any of the
Warrant Certificates shall not have been countersigned, the Warrant Agent may
countersign such Warrant Certificates either in its prior name or in its changed
name; and in all such cases such Warrant Certificates shall have the full force
provided in the Warrant Certificates and in this Agreement.

       

       
Section 18.         Duties of Warrant
Agent.   The Warrant Agent
undertakes the duties and obligations imposed by this Agreement upon the
following terms and conditions, by all of which the Company and the holders of
Warrant Certificate, by their acceptance thereof, shall be bound:

       

      (a)          The
Warrant Agent may consult with legal counsel (who may be legal counsel for the
Company), and the opinion of such counsel shall be full and complete
authorization and protection to the Warrant Agent as to any action taken or
omitted by it in good faith and in accordance with such
opinion.


      
        
           


        

        
          17

          
            

          

        

        
           


        

      


      (b)          Whenever
in the performance of its duties under this Agreement the Warrant Agent shall
deem it necessary or desirable that any fact or matter be proved or established
by the Company prior to taking or suffering any action hereunder, such fact or
matter (unless other evidence in respect thereof be herein specifically
prescribed) may be deemed to be conclusively proved and established by a
certificate signed by the Chairman, President or any Vice President of the
Company and by the Treasurer or any Assistant Treasurer or the Secretary of the
Company and delivered to the Warrant Agent; and such certificate shall be full
authentication to the Warrant Agent for any action taken or suffered in good
faith by it under the provisions of this Agreement in reliance upon such
certificate.

       

      (c)          The
Warrant Agent shall be liable hereunder only for its own gross negligence, bad
faith or willful misconduct, pursuant to Section 16, above.

       

      (d)          The
Warrant Agent shall not be liable for or by reason of any of the statements of
fact or recitals contained in this Agreement or in the Warrant Certificates
(except its countersignature thereof) or be required to verify the same, but all
such statements and recitals are and shall be deemed to have been made by the
Company only.

       

      (e)          The
Warrant Agent shall not be under any responsibility in respect of the validity
of this Agreement or the execution and delivery hereof (except the due execution
hereof by the Warrant Agent) or in respect of the validity or execution of any
Warrant Certificate (except its countersignature thereof); nor shall it be
responsible for any breach by the Company of any covenant or condition contained
in this Agreement or in any Warrant Certificate; nor shall it be responsible for
the adjustment of the Exercise Price or the making of any change in the number
of shares of Common Stock required under the provisions of Sections 10 or
12 or responsible for the manner, method or amount of any such change or the
ascertaining of the existence of facts that would require any such adjustment or
change (except with respect to the exercise of Warrants evidenced by Warrant
Certificates after actual notice of any adjustment of the Exercise Price); nor
shall it by any act hereunder be deemed to make any representation or warranty
as to the authorization or reservation of any shares of Common Stock to be
issued pursuant to this Agreement or any Warrant Certificate or as to whether
any shares of Common Stock will, when issued, be duly authorized, validly
issued, fully paid and nonassessable.

       

      (f)          The
Company agrees that it will perform, execute, acknowledge and deliver or cause
to be performed, executed, acknowledged and delivered all such further and other
acts, instruments and assurances as may reasonably be required by the Warrant
Agent for the carrying out or performing by the Warrant Agent of the provisions
of this Agreement.

       

      (g)          The
Warrant Agent is hereby authorized to accept instructions with respect to the
performance of its duties hereunder from the Chairman or the President or any
Vice President or the Secretary of the Company, and to apply to such officers
for advice or instructions in connection with its duties, and it shall not be
liable and shall be indemnified and held harmless for any action taken or
suffered to be taken by it in good faith in accordance with instructions of any
such officer, provided Warrant Agent carries out such instructions without gross
negligence, bad faith or willful misconduct.


      
        
           


        

        
          18

          
            

          

        

        
           


        

      


      (h)          The
Warrant Agent and any shareholder, director, officer or employee of the Warrant
Agent may buy, sell or deal in any of the Warrants or other securities of the
Company or become pecuniarily interested in any transaction in which the Company
may be interested, or contract with or lend money to the Company or otherwise
act as fully and freely as though it were not Warrant Agent under this
Agreement.  Nothing herein shall preclude the Warrant Agent from
acting in any other capacity for the Company or for any other legal
entity.

       

      (i)          The
Warrant Agent may execute and exercise any of the rights or powers hereby vested
in it or perform any duty hereunder either itself or by or through its attorney
or agents, and the Warrant Agent shall not be answerable or accountable for any
act, default, neglect or misconduct of any such attorney or agents or for any
loss to the Company resulting from any such act, default, neglect or misconduct,
provided reasonable care was exercised in the selection and continued employment
thereof.

       

       
Section 19.         Change of Warrant
Agent.   The Warrant Agent
may resign and be discharged from its duties under this Agreement upon 30 days’
notice in writing mailed to the Company and to each transfer agent of the Common
Stock by registered or certified mail, and to the holders of the Warrant
Certificates by first-class mail.  The Company may remove the Warrant
Agent or any successor Warrant Agent upon 30 days’ notice in writing, mailed to
the Warrant Agent or successor Warrant Agent, as the case may be, and to each
transfer agent of the Common Stock by registered or certified mail, and to the
holders of the Warrant Certificates by first-class mail.  If the
Warrant Agent shall resign or be removed or shall otherwise become incapable of
acting, the Company shall appoint a successor to the Warrant
Agent.  If the Company shall fail to make such appointment within a
period of 30 days after such removal or after it has been notified in writing of
such resignation or incapacity by the resigning or incapacitated Warrant Agent
or by the holder of a Warrant Certificate (who shall, with such notice, submit
his Warrant Certificate for inspection by the Company), then the registered
holder of any Warrant Certificate may apply to any court of competent
jurisdiction for the appointment of a new Warrant Agent.  Any
successor Warrant Agent, whether appointed by the Company or by such a court,
shall be a corporation organized and doing business under the laws of the United
States or of a state thereof, in good standing, which is authorized under such
laws to exercise corporate trust powers and is subject to supervision or
examination by federal or state authority and which has at the time of its
appointment as Warrant Agent a combined capital and surplus of at least
$50,000,000.  After appointment, the successor Warrant Agent shall be
vested with the same powers, rights, duties and responsibilities as if it had
been originally named as Warrant Agent without further act or deed; but the
predecessor Warrant Agent shall deliver and transfer to the successor Warrant
Agent any property at the time held by it hereunder, and execute and deliver any
further assurance, conveyance, act or deed necessary for the
purpose.  Not later than the effective date of any such appointment,
the Company shall file notice thereof in writing with the predecessor Warrant
Agent and each transfer agent of the Common Stock, and mail a notice thereof in
writing to the registered holders of the Warrant
Certificates.  However, failure to give any notice provided for in
this Section 19, or any defect therein, shall not affect the legality or
validity of the resignation or removal of the Warrant Agent or the appointment
of the successor Warrant Agent, as the case may be.


      
        
           


        

        
          19

          
            

          

        

        
           


        

      


       
Section 20.         Issuance of New Warrant
Certificates.  
Notwithstanding any of the provisions of this Agreement or of the Warrants to
the contrary, the Company may, at its option, issue new Warrant Certificates
evidencing Warrants in such form as may be approved by its Board of Directors to
reflect any adjustment or change in the Exercise Price per share and the number
or kind or class of shares of stock or other securities or property purchasable
under the several Warrant Certificates made in accordance with the provisions of
this Agreement.

       

       
Section 21.         Covenants.

       

      (a)          For
so long as any of the Warrants remain outstanding, the Company shall use its
best efforts to maintain the effectiveness of the Registration Statement for the
issuance thereunder of the Warrant Shares.  If at any time following
the date hereof the Registration Statement is not effective or is not otherwise
available for the issuance of the Warrant Shares, the Company shall immediately
notify the holders of the Warrants in writing that the Registration Statement is
not then effective and thereafter shall promptly notify such holders when the
Registration Statement is effective again and available for the issuance of the
Warrant Shares.

       

      (b)          During
the period from the Effective Date until the date on which no Warrants are
outstanding, the Company shall timely file all reports required to be filed with
the SEC pursuant to the Exchange Act, and the Company shall not terminate its
status as an issuer required to file reports under the Exchange Act even if the
Exchange Act or the rules and regulations thereunder would no longer require or
otherwise permit such termination.

       

      (c)          So
long as any Warrants remain outstanding, the Company shall use its reasonable
best efforts to at all times have authorized, and reserved for the purpose of
issuance, no less than 100% of the maximum number of shares of Common Stock
issuable upon exercise of all the Warrants (without regard to any limitations on
the exercise of the Warrants set forth therein), less the number of Warrant
Shares represented by any such Warrants that have been exercised, and all other
convertible securities, options and other instruments of the
Company.

       

       
Section 22.         Notices.   Notices or demands authorized by
this Agreement to be given or made (i) by the Warrant Agent or by the
holder of any Warrant Certificate to or on the Company, (ii) subject to the
provisions of Section 19, by the Company or by the holder of any Warrant
Certificate to or on the Warrant Agent or (iii) by the Company or the
Warrant Agent to the holder of any Warrant Certificate, shall be deemed given
(x) on the date delivered, if delivered personally, (y) on the first
Business Day following the deposit thereof with Federal Express or another
recognized overnight courier, if sent by Federal Express or another recognized
overnight courier, and (z) on the fourth Business Day following the mailing
thereof with postage prepaid, if mailed by registered or certified mail (return
receipt requested), in each case to the parties at the following addresses (or
at such other address for a party as shall be specified by like
notice):


      
        
           


        

        
          20

          
            

          

        

        
           


        

      


      (a)         If
to the Company, to:

       

        Repros
Therapeutics, Inc.

       
2408 Timberloch Place. B-7

       
The Woodlands, Texas 77380

       
Attention: Joseph S. Podolski

       
Telecopy: (281) 719-3446

        

      (b)         If
to the Warrant Agent, to:

       

       
Computershare Trust Company, N.A.

       
250 Royall Street

       
Canton, Massachusetts 02021

       
Attention: Client Administration

       
Telecopy:  (781) 575-2549

        

      (c)          If
to the holder of any Warrant Certificate, to the address of such holder as shown
on the registry books of the Company.  Any notice required to be
delivered by the Company to the registered holder of any Warrant may be given by
the Warrant Agent on behalf of the Company.

       

       
Section 23.         Supplements and
Amendments

      
         


      

      (a)          The
Company and the Warrant Agent may from time to time supplement or amend this
Agreement without the approval of any holders of Warrant Certificates in order
to cure any ambiguity, to correct or supplement any provision contained herein
which may be defective or inconsistent with any other provisions herein, or to
make any other provisions with regard to matters or questions arising hereunder
which the Company and the Warrant Agent may deem necessary or desirable and
which shall not adversely affect the interests of the holders of Warrant
Certificates.

       

      (b)          In
addition to the foregoing, with the consent of holders of Warrants entitled,
upon exercise thereof, to receive not less than 66 2/3% of the shares of Common
Stock issuable thereunder, the Company and the Warrant Agent may modify this
Agreement for the purpose of adding any provisions to or changing in any manner
or eliminating any of the provisions of this Warrant Agreement or modifying in
any manner the rights of the holders of the Warrant Certificates; provided, however, that no
modification of the terms (including but not limited to the adjustments
described in Section 10) upon which the Warrants are exercisable or
reducing the percentage required for consent to modification of this Agreement
may be made without the consent of the holder of each outstanding Warrant
Certificate affected thereby.


      
        
           


        

        
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Section 24.         Successors.   All covenants and provisions of
this Agreement by or for the benefit of the Company or the Warrant Agent shall
bind and inure to the benefit of their respective successors and assigns
hereunder.

       

       
Section 25.         Benefits of this
Agreement.  Nothing
in this Agreement shall be construed to give any Person, other than the Company,
the Warrant Agent and the registered holders of the Warrant Certificates, any
legal or equitable right, remedy or claim under this Agreement; but this
Agreement shall be for the sole and exclusive benefit of the Company, the
Warrant Agent and the registered holders of the Warrant
Certificates.

       

       
Section 26.         Governing Law.   This Agreement and each Warrant
Certificate issued hereunder shall be governed by, and construed in accordance
with, the laws of New York without giving effect to the conflicts of law
principles thereof.

       

       
Section 27.         Counterparts.   This Agreement may be executed in
any number of counterparts and each of such counterparts shall for all purposes
be deemed to be an original, and all such counterparts shall together constitute
but one and the same instrument.

       

       
Section 28.         Captions.   The captions of the sections of
this Agreement have been inserted for convenience only and shall not control or
affect the meaning or construction of any of the provisions hereof.

       

       
Section 29.         Information.   The Company agrees to promptly
provide the registered holders of the Warrants the information it is required to
provide to the holders of the Common Stock.

       

       
Section 30.         Force Majeure.   Notwithstanding anything to the
contrary contained herein, Warrant Agent shall not be liable for any delays or
failures in performance resulting from acts beyond its reasonable control
including, without limitation, acts of God, terrorist acts, shortage of supply,
breakdowns or malfunctions, interruptions or malfunction of computer facilities,
or loss of data due to power failures or mechanical difficulties with
information storage or retrieval systems, labor difficulties, war, or civil
unrest.

       

       
Section 31.         Confidentiality.  The Warrant Agent (or Co-Warrant
Agent, if any) and the Company agree that all books, records, information and
data pertaining to the business of the other party, including inter alia,
personal, non-public warrant holder information, which are exchanged or received
pursuant to the negotiation or the carrying out of this Agreement including the
fees for services set forth in the attached schedule shall remain confidential,
and shall not be voluntarily disclosed to any other person, except as may be
required by law.

        

      [Remainder
of Page Intentionally Left Blank]

        

      
        
           


        

        
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      IN
WITNESS WHEREOF, the parties hereto have caused this Agreement to be duly
executed as of the day and year first above written.

       

      
        
          	
                  REPROS
      THERAPEUTICS INC.

                
	 
      
	
                  By:

                	
                      

                
	 
      	
                  Name:

                
	 
      	
                  Title:

                
	 
      
	
                  COMPUTERSHARE
      TRUST COMPANY, N.A.

                
	 
      	 
      
	
                  By:

                	
                      

                
	 
      	
                  Name:

                
	 
      	
                  Title:

                
	 
      
	
                  COMPUTERSHARE
      INC.

                
	 
      	 
      
	
                  By:

                	
                      

                
	 
      	
                  Name:

                
	 
      	
                  Title:

                


        

      

       

      
        
           


        

        
          23