EXHIBIT
      10.21

     

    CONFIDENTIAL
      TREATMENT REQUESTED. Confidential portions of this document have been redacted
      and have been separately filed with the Commission.

     

    LICENSE
      AGREEMENT

     

    THIS
      LICENSE AGREEMENT
      (the “Agreement”), effective as of this 7th
      day of November 2005 (the “Effective Date”), by and between Panion & BF
      Biotech, Inc., with offices at 16F No. 3, Yuanqu Street, Nangang District,
      Taipei, Taiwan, ROC (hereinafter "Licensor"), and Keryx Biopharmaceuticals,
      Inc,
      with offices at 750 Lexington, 20th
      Floor, New York, NY 10022 (hereinafter "Licensee").

     

    WHEREAS,
      Dr. Chen Hsing Hsu (the "Inventor"), an employee of the University of Michigan
      (the "Institution"), is the named inventor on U.S. Patent No. 5,753,706, issued
      May 19, 1998 and entitled "Methods for Treating Renal Failure" (the "Licensed
      Patent Property"),

     

    WHEREAS,
      the Institution has transferred to the Inventor all of the Institution's right,
      title, and interest in and to the Licensed Patent Property (subject to certain
      non-commercial applications, specified below), by an Agreement for the
      Reassignment of Intellectual Property, with a last-signed date of August 16,
      2000,

     

    WHEREAS,
      the Inventor has granted the Licensor the exclusive license, throughout the
      world (except the People's Republic of China) to make, use, and sell products
      embodying the inventions described in the Licensed Patent Properties, as well
      as
      rights to the Patent Rights (as hereinafter defined) (as specified below) (the
      "Exclusive License"),

     

    WHEREAS,
      Licensor has developed certain Licensor Know-How (as hereinafter
      defined),

     

    WHEREAS,
      by operation of this exclusive license, Licensor is the sole and exclusive
      licensee of the entire right, title and interest in and to the Patent Rights
      (with the exception of the People's Republic of China) and Licensor
      Know-How,

     

    WHEREAS,
      Licensee desires to obtain an exclusive license under such Patent Rights and
      Licensor Know-How to develop, have developed, make, have made, use, have used,
      offer to sell, sell, have sold, import and export the Compound and Product
      in
      the Territory (as hereinafter defined), and

     

    WHEREAS,
      Licensor has the authority and is willing to grant such license to Licensee,
      and
      Licensee is willing to accept such license from Licensor, under the terms and
      conditions set forth in this Agreement.

     

    NOW
      THEREFORE,
      in consideration of the mutual promises and covenants set forth herein and
      other
      good and valuable consideration, the receipt of which is hereby acknowledged,
      the parties hereto agree as follows:

     

    
      
        
        

      

      
        
        

        
          

        

      

      
        
        

      

    

     

    ARTICLE
      1. DEFINITIONS

     

    As
      used in this Agreement, the following terms, whether used in the singular or
      the
      plural, shall have the following meanings:

     

    1.1
      "Affiliate"
      means any corporation or non-corporate business entity, which controls, is
      controlled by, or is under common control with a party to this Agreement. A
      corporation or non-corporate business entity shall be regarded as in control
      of
      another corporation if it owns or directly or indirectly controls at least
      fifty-one percent (51%) of the voting stock of the other corporation, or (i)
      in
      the absence of the ownership of at least fifty-one percent (51%) of the voting
      stock of a corporation, or (ii) in the case of a non-corporate business entity,
      if it possesses, directly or indirectly, the power to direct or cause the
      direction of the management and policies of the corporation or non-corporate
      business entity, as applicable.

     

    1.2
       “Combination
      Product”
      means a Product containing one or more therapeutically active ingredients in
      addition to the Compound.

     

    1.3 "Compound"
      means ferric citrate (PBF1681).

     

    1.4
       "FDA"
      means the United States Food and Drug Administration.

     

    1.5 “Field”
      means the field of nephrology.

     

    1.6 “First
      Commercial Sale”
      means with respect to a Product, the first sale for end use or consumption
      of
      such Product in a country after all Registrations in such country have been
      obtained.

     

    1.7
       "IND"
      means an Investigational New Drug Application in the United States.

     

    1.8
       "Indication"
      means any therapeutic application for a Product (i) for the treatment of
      hyperphosphatemia in end-stage renal disease, and (ii) for all other indications
      covered by the Patent Rights. 

     

    1.9 “Improvements”
      means any and all improvements, materials, technical data and information
      whether patented or unpatented, including but not limited to any changes to
      the
      Compound, to the Product or in the Licensor Know-How or Licensee Know-How
      including, but not limited to any analogues, or derivatives of the Compound,
      and
      changes in the manufacturing process for the Compound or the Product which
      are
      conceived or reduced to practice during the term of this Agreement.


     

    1.10
      “Licensee
      Development Data”
      means and includes all data relating to the Compound or the Product and all
      chemistry, manufacturing and control data relating to the development and
      manufacture of the Compound or the Product, results of pre-clinical and clinical
      studies and all other documentation containing or embodying any pre-clinical,
      clinical, chemistry, manufacturing and control data relating to any application
      for Registrations for a Product, which is generated by Licensee, its agents,
      or
      any Sublicensees during the term of this Agreement.

     

    1.11 “Licensee
      Know-How”
      means all information and materials, including but not limited to, discoveries,
      processes, instructions, formulas, data, inventions, know-how and trade secrets,
      patentable or otherwise, which arise out of the development, manufacture and
      commercialization by Licensee of the Compound or the Product, including, without
      limitation, all biological, chemical, pharmacological, toxicological,
      pharmaceutical, physical, analytical, clinical, safety, manufacturing and
      quality control data and information related thereto, and all applications,
      registrations, licenses authorizations, documents, approvals and correspondence
      relating to the Compound or the Product, including without limitation,
      correspondence submitted to Regulatory Authorities, and all information and
      data
      contained in Registrations. Licensee Know-How shall also include Licensee’s
      interest in Improvements.

     

    
      
        
        

      

      
        2

        
          

        

      

      
        
        

      

    

     

    1.12
      “Licensor
      Development Data”
      means and includes all data to which Licensor has rights relating to the
      Compound or the Product and all chemistry, manufacturing and control data
      relating to the development and manufacture of the Compound or the Product,
      results of pre-clinical and clinical studies and all other documentation
      containing or embodying any pre-clinical, clinical, chemistry, manufacturing
      and
      control data relating to any application for Registrations for the Product,
      whether such Licensor Development Data is in existence as of the Effective
      Date
      or generated by Licensor during the term of this Agreement.

     

    1.13
       "Licensor
      Know-How” means all information and materials to which Licensor has rights,
      including but not limited to, discoveries, processes, formulas, instructions,
      data, inventions, know-how and trade secrets, patentable or otherwise, in each
      case, which as of the Effective Date and during the term of this Agreement
      are
      necessary or useful to Licensee in connection with the development,
      registration, manufacture, marketing, use or sale of a Product. Licensor
      Know-How shall also include without limitation, all biological, chemical,
      pharmacological, toxicological, pharmaceutical, physical, analytical, clinical,
      safety, manufacturing and quality control data and information related thereto,
      and all applications, registrations, licenses, authorizations, documents,
      approvals and correspondence relating to a Licensed Compound or a
      Product. Licensor
      Know-How shall also include Licensor’s interest in Improvements. 

     

    1.
      14  "NDA"
      means a New Drug Application in the United States.

     

    1.15 "Net
      Sales"
      with respect to any Product other than a Combination Product means the gross
      sales (i.e. gross invoice prices) of such Product billed by Licensee and its
      Sublicenses to Third Party customers on all sales of a Product, and exclusive
      of
      inter-company transfer or sales, less the reasonable and customary deductions
      from such gross sales, including: 

     

    (i)
      actual credited allowances to such Third Party customers for spoiled, damaged,
      outdated and returned Product and for retroactive price reductions,


     

    (ii)
      the amounts of trade, cash discounts and rebates, to the extent such discounts
      and rebates were not deducted by Licensee or its Sublicensees at the time of
      invoice in order to arrive at the gross invoice prices, 

     

    (iii)
      all transportation, handling charges and freight insurance, sales taxes, excise
      taxes, use taxes or import/export duties paid, and 

     

    (iv)
      all other reasonable and customary allowances and adjustments actually credited
      to customers whether during the specific royalty period or not.

     

    
      
        
        

      

      
        3

        
          

        

      

      
        
        

      

    

     

    The
      sale of a Product between Licensee and any of its Sublicensees solely for the
      research or clinical testing of such Product shall be excluded from the
      computation of Net Sales of such Product, provided that Licensee's sale of
      the
      Product was at cost, and such Product was used for research or clinical testing.
       

     

    1.16
      "Net
      Sales"
      with respect to any Combination Product means the gross sales of such Product
      billed by Licensee and its Sublicensees to Third Party customers, on all sales
      of a Combination Product, and exclusive of inter-company transfer or sales,
      less
      all the allowances, adjustment, reductions, discounts, taxes, duties and other
      charges referred to in Section 1.15,
      multiplied by a fraction
      to be determined
      by Licensor and Licensee at such time when the Combination Product becomes
      available.   

     

    The
      sale of a Combination Product between Licensee and any of its Sublicensees
      solely for the research or clinical testing of such Product shall be excluded
      from the computation of Net Sales for such Combination Product, provided that
      Licensee's sale of the Combination Product was at cost, and such Combination
      Product was used for research or clinical testing.  

     

    1.17
      "Patent
      Rights"
      means the Licensed Patent Property,
      and the patents and patent applications set forth in Exhibit
      1
      (which shall be updated from time to time by Licensor), patents and patent
      applications in which Licensor holds rights and which are directed to Licensor’s
      interest in Improvements, and any and all patents in which Licensor holds rights
      and that may issue from all such patent applications, including any and all
      divisions, continuations, continuations-in-part, extensions, substitutions,
      renewals, registrations, supplementary protection certificates, revalidations,
      reissues or additions of or to any of the aforesaid patents and patent
      applications, and any additional patents or patent applications to which
      Licensor acquires rights during the term of this Agreement which pertain in
      any
      way to the use or manufacture of the Compound or the Product. 

     

    1.18 “Payment
      Default”
      means Licensee’s failure to pay Licensor the license fee and milestone payments
      under Article 4, and the royalties under Article 5 for more than 90 days past
      the date on which these amounts are due.

     

    1.19 "Product"
      means the Compound or any pharmaceutical product containing the Compound as
      an
      active ingredient, either alone or in combination with other active
      ingredients.

     

    1.20 “Proprietary
      Information”
      means all information, including without limitation all Licensee Know-How,
      Licensor Know-How, and all other scientific, clinical, regulatory, marketing,
      financial and commercial information or data, whether communicated in writing,
      orally or electronically which is provided by one party to the other party
      in
      connection with this Agreement. 

     

    1.21
       "Registration"
      in relation to any Product means such approvals by a Regulatory Authority in
      a
      country or community or association of countries as may be legally required
      before such Product may be commercialized in such country or community or
      association of countries.

     

    
      
        
        

      

      
        4

        
          

        

      

      
        
        

      

    

     

    1.22
       “Regulatory
      Authority”
      means the applicable government regulatory authority in each country in the
      Territory involved in granting regulatory approval for the Product. Such term
      includes, without limitation, the FDA and any successor agency thereto and
      Committee on Proprietary Medicinal Products of the European Community and any
      successor agency thereto

     

    1.23
       “Sublicensee”
      means a Third Party to which Licensee has granted sublicense rights under the
      license granted Licensee hereunder, which rights include at least the right
      to
      sell the Product. Third Parties that are permitted to manufacture the Compound
      or the Product for supply only to Licensee or only to Sublicensees are not
      “Sublicensees” and such transaction shall be deemed a transfer and not a sale of
      the Product. 

     

    1.24 "Territory"
      means the entire world, provided that (a) excluded from the Territory
      are
      China, Korea, and all other countries in the Asian Pacific Region, except that
      (b) included within the Territory is
      Japan.

     

    1.25
       "Third
      Party"
      means any party other than Licensor or Licensee or their respective Affiliates,
      or Sublicensees of Licensee or its Sublicensees.

     

    1.26
       "Valid
      Claim"
      means a claim of an issued and unexpired patent included within the Patent
      Rights which has not been held unenforceable or invalid in the applicable
      jurisdiction by a decision of a court or other governmental agency of competent
      jurisdiction, unappealable or unappealed within the time allowed for appeal,
      and
      which has not been admitted to be invalid or unenforceable through dedication,
      disclaimer or otherwise.

     

    ARTICLE
      2. REPRESENTATIONS AND WARRANTIES

     

    2.1 Each
      party represents and warrants to the other party that it has the full right
      and
      authority to enter into this Agreement, and that, to the best of its knowledge,
      there are no prior agreements, commitments or other obstacles which could
      prevent it from carrying out all of its obligations hereunder. 

     

    2.2 Licensor
      represents to Licensee that:

     

    (a) it
      is the exclusive licensee of the entire right, title and interest in and to
      the
      Patent Rights, and to the best of its knowledge, there
      are no charges, encumbrances, licenses, options,
      restrictions, liens, rights of others, disputes, proceedings or claims relating
      to, affecting, or limiting its rights or the rights of
      Licensee under this Agreement, with the exception of non-commercial uses of
      the
      Licensed Patent Properties reserved to the Institution; 

     

    (b) there
      is no claim, pending
      or threatened, of infringement, interference or invalidity regarding
any
      part or all of the Patent Rights and their use as contemplated in this
      Agreement, and it has no present knowledge from which it can be inferred that
      the Patent Rights are invalid or that their exercise would infringe the patent
      rights of any Third Party;

     

    
      
        
        

      

      
        5

        
          

        

      

      
        
        

      

    

     

    (c) it
      has the right to enter into this Agreement and to grant the licenses granted
      herein,
      and
      there is nothing in any Third Party agreement Licensor has entered into as
      of
      the Effective Date, which in any way, will limit the ability of Licensor to
      perform any and all of
      the obligations undertaken by Licensor hereunder, 

     

    (d) it
      will not enter into any agreement after the Effective Date which will limit
      its
      ability to perform any and all of the obligations undertaken by Licensor
      hereunder

     

    (e) it
      has delivered to Licensee all Licensor Development Data and Licensor Know-how;
      and

     

    (f) to
      the best of its knowledge,
      neither this Agreement, nor any document or piece of Licensor Development Data,
      Licensor Know-How or Patent Rights contains any untrue statement of a material
      fact or omits to state a material fact necessary in order to make the statements
      contained herein or therein misleading.

     

    2.3 Licensee
      represents to Licensor that:

     

    (a) it
      has the right to enter into this Agreement and to the best of its knowledge,
      there
      is nothing in any Third Party agreement Licensee
      has
      entered into as of the Effective Date, which in any way, will limit the ability
      of Licensee
      to perform any and all of the obligations undertaken by Licensee hereunder,
      and

     

    (b) it
      will not enter into any agreement after the Effective Date which will limit
      its
      ability to perform any and all of the obligations undertaken by Licensee
      hereunder.

     

    ARTICLE
      3. LICENSE GRANT

     

    3.1 Grant.
      Subject to the terms and conditions of this Agreement, Licensor hereby grants
      to
      Licensee an exclusive license, in the Territory, with the right to sublicense,
      to develop, have developed, make, have made, use, have used, offer to sell,
      sell, have sold, and import and export the Product in the Territory under the
      Licensor Know-How, and the Patent Rights for all Indications in the Field.
      

     

    3.2 Sublicensing. Sublicensees
      of Licensee shall be entitled to sublicense to third parties the right to
      manufacture the Product, provided such third party manufacturers are permitted
      to sell only to Licensee or its immediate Sublicensees. Sublicensees of Licensee
      may not grant sublicenses under this Agreement without the written consent
      of
      Licensor, which consent shall
      not be unreasonably withheld or delayed. Should Licensee or any Sublicensee
      of
Licensee
      grant any sublicenses, the terms and conditions of such sublicenses and the
      identity of sublicensees shall be at the sole discretion of Licensee and no
      consent shall be required from Licensor in connection with the terms and
      conditions of such sublicenses or the identity of sublicensees, provided
      however, that such sublicenses shall be co-terminated with this
      Agreement.

     

    3.3 Consent
      of Inventor.
      The Inventor has provided his written consent to the terms and conditions of
      the
      License Grant and the terms and conditions of this Agreement. The Written
      Consent of the Inventor is set forth in Exhibit
      2
      hereto.

     

    
      
        
        

      

      
        6

        
          

        

      

      
        
        

      

    

    *****Confidential
      material redacted and filed
      separately with the Commission.

     

    ARTICLE
      4. LICENSE FEE; MILESTONE PAYMENTS

     

    4.1
       License
      Fee.
      Licensee will pay to Licensor a non-refundable, non-creditable license fee
      of
      ***** in cash on or about the Effective Date. 

     

    4.2
       Milestone
      Payments.
      Licensee will pay to Licensor the milestone payments as follows:

     

    (a)
      Within one hundred twenty (120) days following completion of Phase II clinical
      trial: *****;

     

    (b)
      Within one hundred twenty (120) days following submission to the FDA of the
      first New Drug Application for a Product: *****;

     

    (c)
      Within one hundred and twenty (120) days following a first FDA marketing
      approval for a Product: *****;

     

    (d)
      Within one hundred and twenty (120) days following a first marketing approval
      for a Product in any country in Europe: *****; and

     

    (e)
      Within one hundred and twenty (120) days following a first marketing approval
      for a Product in Japan: *****.

     

    4.3  Limitations.
      It is understood and agreed that Licensee shall pay the milestone payments
      set
      forth in Section 4.2 only with respect to
      the first Indication for
      which a Product achieves a particular milestone event, and regardless of the
      number of Products which achieve a particular milestone event.

     

    4.4
      Payment
      in Equity.
      At Licensee’s option, up to ***** or such greater amount as may be mutually
      agreed by Licensor and Licensee of any milestone payment due pursuant to
      Sections 4.2(b) and (c) can be made in shares of unrestricted, unlegended and
      freely tradable common stock of Licensee, based on a per share price equal
      to
      the average closing price as listed in the Wall Street Journal over the last
      thirty (30) business days immediately preceding the date of a particular
      milestone payment is due; provided that (i) the Licensee’s common stock is
      traded on the NASDAQ National Market or other national stock exchange in the
      U.S. at the time the payment is made; (ii) the average trading price of such
      shares of common stock on the NASDAQ National Market or
      other national stock exchange in the U.S. in the three (3) months period
      immediately preceding the last day of
      a particular milestone payment pursuant to Sections 4.2(b) or (c) is due exceeds
      ***** and (iii) the ***** immediately
      preceding the payment due date exceeds *****. It
      is understood and agreed that the Licensee has the right to refuse any or all
      payment in the form of stock by the Licensor pursuant to this Section 4.4 if
      the
      Licensor has reasons to believe that the stock delivered is not unrestricted,
      unlegended or freely tradable.

     

    
      
        
        

      

      
        7

        
          

        

      

      
        
        

      

    

    *****Confidential
      material redacted and filed
      separately with the Commission.

     

    ARTICLE
      5. ROYALTIES

     

    5.1
       Royalties.
      In consideration of the license rights granted to Licensee hereunder, Licensee
      shall pay or cause any
      Sublicensee 
      to pay to
      Licensor a royalty on their
      respective Net
      Sales,
      as follows:

     

    for
      each Product where the manufacture, use or sale of such Product would but for
      the license granted hereunder, infringe a Valid Claim a royalty of *****
      on
      Net Sales. 

     

     5.2 Limitation.
      If the laws of any country where royalties are payable under Section 5.1 limit
      the amount of royalty or the duration of such royalty payments to less than
      the
      amount specified herein, then the royalty payment to Licensor shall be limited
      to that permitted by law. 

     

    5.3
       Accrual
      of Royalties.
      No royalty shall be payable on a Product made, sold, or used for testing or
      development purposes or distributed as samples, provided such samples are sold
      by Licensee (or its Sublicensee) at cost. No royalties shall be payable on
      sale
      among Licensee and its Sublicensees, but royalties shall be payable on
      subsequent sales by Licensee or its Sublicensees to a Third Party. No multiple
      royalty shall be payable because the manufacture, use, or sale of a Product
      is
      covered by more than one Valid Claim. 

     

    5.4
       Royalty
      Withheld
      due to Invalid Claims.
      In the event that all applicable claims of a patent included within the Patent
      Rights under which Licensee is paying a royalty according to Section 5.1 shall
      be held invalid or unenforceable by a court of competent jurisdiction in a
      given
      country of the Territory, Licensee may withhold payments of royalties which
      would otherwise have been due on Net Sales in that country by reason of Section
      5.1 until such judgment shall be finally reviewed by an unappealed or
      unappealable decree of a higher court of competent jurisdiction in such country.
      The Licensee shall promptly repay Licensor any withheld royalty payments
 upon
      a final adjudication that the applicable claims of a patent included within
      the
      Patent Rights under which Licensee is paying a royalty under Section 5.1 are
      valid and enforceable. 

     

    5.5 Compulsory
      Licenses.
      If Licensee is caused to grant a compulsory license to any Third Party with
      respect to a Product in any country in the Territory, then the royalty rate
      to
      be paid by Licensee on Net Sales due on such Product in that country under
      Section 5.1 shall be reduced to the rate paid by such Third Party compulsory
      licensee on such Product. 

     

    ARTICLE
      6. ROYALTY REPORTS AND ACCOUNTING

     

    6.1
       Royalty
      Reports and Records.
      Beginning with the First Commercial Sale by Licensee or any Sublicensee as
      the
      case may be of a Product in any country of the Territory, and continuing
      thereafter during the term of this Agreement, Licensee shall furnish,
      and shall cause any Sublicensee to furnish,
      to Licensor a written report covering each calendar quarter (the "Reporting
      Period") showing (a) the Net Sales of each Product in each country of the
      Territory where royalties are payable under Section 5.1 during the Reporting
      Period; (b) the royalties, payable in United States Dollars, which shall have
      accrued hereunder in respect of such sales with a summary computation of such
      royalties; (c) withholding taxes, if any required by law to be deducted in
      respect of such sales; and (d) the exchange rates used in determining the amount
      of United States Dollars payable in respect of sales outside the United States.
      With respect to sales of a Product invoiced in a currency other than United
      States Dollars, the Net Sales and royalty payable shall be expressed in the
      domestic currency of the party making the sale together with the United States
      Dollars equivalent of the royalty payable, calculated using the simple average
      of the exchange rate published in the Wall Street Journal on the last day of
      each month of the Reporting Period. If any Sublicensee makes any sale invoiced
      in a currency other than its domestic currency, the Net Sales shall be converted
      to its domestic currency in accordance with its normal accounting principles.
      Licensee's Sublicensees shall have the option of making any royalty payment
      directly to Licensor. However, notwithstanding anything to the contrary, the
      Licensee shall continue to be liable for all royalties due under Section 5.1
      until they are paid. Licensee or its Sublicensee shall furnish to Licensor
      appropriate evidence of payment of, and itemize any tax, credits or specific
      amount deducted from any royalty payment.

     

    
      
        
        

      

      
        8

        
          

        

      

      
        
        

      

    

     

    6.2
       Royalty
      Reports and Payments.
      Royalty reports and payments shall be due sixty (60) days after the close of
      each Reporting Period. Payment of royalties in whole or in part may be made
      in
      advance of such due date. In case no royalty is due for any given Reporting
      Period, Licensee shall so report to Licensor. Licensee and its Sublicensees
      shall keep accurate records in sufficient detail to enable the royalty payable
      hereunder to be determined and confirmed. Licensee shall be responsible for
      all
      royalties, late payments, and interest that are due but have not been paid
      by
      Licensee's Sublicensees.

     

    6.3
       Right
      to Audit.
      Upon written request of Licensor, but not more than once in each calendar year
      nor more than once in respect to any given calendar year, Licensee shall permit
      an independent public accountant, selected by Licensor and acceptable to
      Licensee, which acceptance shall not be unreasonable withheld, to have access
      during normal business hours to those records of Licensee as may be reasonably
      necessary to verify the accuracy of the royalty reports hereunder in respect
      of
      any calendar year ending not more than thirty-six (36) months prior to the
      date
      of such request. Licensee shall include in each Sublicense granted by it
      pursuant to this Agreement a provision requiring the Sublicensee to keep and
      maintain records of sales made pursuant to such sublicense and to grant the
      same
      right of access to such records to Licensor's independent accountant. Upon
      the
      expiration of thirty-six (36) months following the end of any calendar year,
      the
      calculation of royalties payable with respect to such calendar year shall be
      binding and conclusive upon the parties, and Licensee and its Sublicensees
      shall
      be released from any liability or accountability with respect to
      royalties
      (and Licensor for an overpayment of royalties)
      for such calendar year, unless (a) an audit requested by Licensor prior to
      expiration of such thirty-six (36) months period has not yet been completed,
      or
      (b) Licensor has notified Licensee prior to the expiration of such thirty-six
      (36) months period that such audit has revealed a discrepancy regarding such
      calculation. The report prepared by such independent public accountant, a copy
      of which promptly shall be provided to Licensee, shall disclose only the amount
      of any underpayment or overpayment of royalties, if any, without disclosure
      of
      or reference to supporting documentation. If such independent accountant's
      report shows any underpayment of royalties, Licensee shall remit or shall cause
      its Sublicensees to remit to Licensor the amount of such underpayment within
      thirty (30) days after Licensee's receipt of such report, and if such
      underpayment exceeds five percent (5%) of the royalty due, Licensee shall
      reimburse Licensor for its reasonable out-of-pocket expenses for the audit,
      upon
      submission of supporting documentation. Any
      overpayment of royalties shall be creditable against future royalties payable
      in
      subsequent royalty periods, allocated evenly over the next-following two (2)
      royalty periods. In
      the event this Agreement is terminated or expires before such overpayment is
      fully credited, Licensor shall pay Licensee the portion of such overpayment
      not
      credited within one hundred twenty (120) days after
      the date of such termination or expiration.

     

    
      
        
        

      

      
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    *****Confidential
      material redacted and filed
      separately with the Commission.

     

    6.4
       Confidentiality
      of Records.
      Licensor agrees that all information subject to review under Section 6.3 or
      under any sublicense agreement shall be deemed the Proprietary Information
      of
      Licensee. 

     

    6.5
       Late
      Payment Interest.
      Royalties and other payments required to be paid by Licensee pursuant to this
      Agreement shall, if overdue, bear interest at the rate equal to two percent
      (2%)
      over the prime rate as quoted by Citibank NA and not to exceed ten percent
      (10%)
      per annum.
      until paid. The payment of such interest shall not preclude Licensor from
      exercising any other rights it may have because any payment is
      overdue.

     

    ARTICLE
      7. DEVELOPMENT AND MARKETING PROGRAM

     

    7.1
      Clinical
      Development Program.
      Licensee shall pay,
      within thirty (30) days from the receipt of valid invoices from
      Licensor,
      ***** of all costs for Licensor's current Phase II clinical trial up to a
      maximum of *****, and shall at its expense, use commercially reasonable best
      efforts (a) to conduct a clinical development program directed to obtaining
      FDA
      approval of at least one Product for at least one Indication to be selected
      by
      Licensee (the "Development Program"), and (b) if, in the opinion of Licensee,
      the results of the Development Program so justify, to diligently seek FDA
      approval for such Product for such Indication. For purposes of this Section,
      "commercially reasonable best efforts" shall mean efforts consistent with those
      used by Licensee in its own priority development projects with its own products
      deemed to have high commercial potential. 

     

    7.2
       Fulfillment.
      Licensee's reasonable efforts set forth in Section 7.1
      with respect to the US shall
      be deemed to have been fulfilled if Licensee 

     

    (a)
      *****

     

    (b)
      ***** 

     

    For
      purposes of this Section 7.2, *****. All clinical studies are to be conducted
      under an IND in the United States, or if conducted by Licensee outside the
      United States, are to be acceptable to the FDA for Registration of a Product
      in
      the United States.
      While fulfilling or in Licensee’s discretion, upon fulfillment of the above
      obligations, Licensee shall use commercially reasonable best efforts to
      commercialize the Product outside the US, within the Territory.

     

    
      
        
        

      

      
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      7.3
       Suspension
      of Development Program.
      Licensee’s obligation to conduct the Development Program is expressly
      conditioned on the continuing absence of any event or condition (such as, but
      not limited to, a regulatory action affecting the Product or the existence
      of an
      issue relating to the safety or efficacy of the Product, the introduction of
      a
      therapy which has superior safety and/or efficacy, or the existence of any
      circumstances, economic or otherwise, which make the development or marketing
      of
      the Product, in Licensee’s judgment, commercially unrewarding) that would
      suggest to Licensee, in exercising prudent and justifiable business judgment,
      that development or marketing of the Product should be suspended or stopped
      altogether, and Licensee’s obligation to develop or market the Product may be
      suspended for up to six (6) months, after which time the Development Program
      shall be resumed or this Agreement may be terminated by Licensor, at the sole
      discretion of Licensor. 

     

     7.4 Assistance
      by Licensor.
      Licensor shall assist Licensee as follows:

     

    (a) As
      soon as practical after the Effective Date, Licensor will make available to
      Licensee all Licensor Development Data in the possession of Licensor, and will
      cooperate with and provide reasonable assistance to Licensee in its evaluation
      of such Licensor Development Data. On a continuing basis during the term of
      this
      Agreement, Licensor shall make available to Licensee all additional Licensor
      Development Data generated by Licensor or any Third Party on behalf of Licensor.
      Licensor shall provide Licensee with a right of reference to all such Licensor
      Development data and Licensee shall have the right to include such Licensor
      Development Data in any of its applications for Registrations. All such Licensor
      Development Data shall be deemed the Proprietary Information of Licensor, and
      all right, title and interest in and to such Licensor Development Data shall
      remain vested in Licensor. 

     

    (b) In
      the event that Licensor receives any inquiries from any Regulatory Authority
      which may affect the development and marketing of a Product, Licensor shall
      immediately notify Licensee. Licensor agrees to assist Licensee in formulating
      a
      response to such inquiries, including being available to meet with the
      Regulatory Authority at a time and place acceptable to Licensor. Licensee shall
      reimburse Licensor for its reasonable expenses incurred in rendering such
      assistance, upon presentation by Licensor of an invoice documenting such
      expenses.

     

    7.5 Registrations.
      Subject to the terms and conditions of this Agreement, each application for
      Registration shall be filed in the name of Licensee or a designated Affiliate.
      Licensee shall own all right, title and interest in and to all applications
      for
      Registrations and granted Registrations. Licensee shall be responsible for
      all
      disclosures and correspondence to and with the Regulatory Authorities, and
      all
      disclosures and correspondence with any Regulatory Authority involving Licensor
      shall be made through Licensee. Licensee shall keep Licensor advised of the
      status of all Registrations and any applications for Registration.

     

    
      
        
        

      

      
        11

        
          

        

      

      
        
        

      

    

    *****Confidential
      material redacted and filed
      separately with the Commission.

     

    7.6
      Licensee
      Development Data.
      All Licensee Development Data shall be deemed the Proprietary Information of
      Licensee, and all right, title and interest in and to such Licensee Development
      Data shall vest in Licensee, subject to Section 12.4.2. 

     

    7.7 Production
      of Clinical Supplies of the Compound.

     

    (a)
      Both
      parties agree to work in good faith to fully collaborate to review and
      administer the manufacturing program for the Compound and to resolve any
      technical issues both immediately after the Effective Date and at least annually
      thereafter during *****.

     

    (b)
      For
      the period commencing on the Effective Date and continuing for
***** following Registration in the United States *****
Licensee (and its Sublicensees) *****. In
      consideration for such supply, Licensee shall provide compensation to Licensor
      at ***** over Licensor's manufacturing
      and procurement
      cost. Notwithstanding the preceding two sentences, decisions and actions related
      to pharmaceutical development and manufacturing of the Clinical Supplies are
      subject to joint review and approval. *****.

     

    (c)
      As
      requested by Licensee, *****, Licensor shall make its best
      efforts to assist Licensee *****.  Licensor shall provide
      assistance to Licensee to transfer any know-how and technology from
***** of Licensor to ***** by Licensee
*****. 

     

    (d)
      In
      the event that either party elects to procure Clinical Supplies from the
      other
      *****,
      in consideration for such clinical supplies, the supplies shall be transferred
      at ***** over
      manufacturing and
      procurement cost. 

     

    7.8
      Indications
      Outside the Field.
      

     

    7.8.1 For
      any indications or line extensions developed by Licensor utilizing the
      Compound
      outside the Field, Licensee shall have a Right of First Negotiation
      and
      Right of First Refusal (as such terms are defined below) as follows:


     

    (a)
      Right
      of First Negotiation.
      If Licensor conceives of an indication or line extension utilizing the Compound
      outside the Field (a “New Development”), Licensor shall provide Licensee a right
      of first negotiation (the “Right of First Negotiation”)
      as follows Licensor shall describe the New Development in writing in reasonable
      detail, and such description shall be protected as Proprietary Information
      under
      this Agreement (a "Confidential Disclosure”). If Licensor conceives of an
      indication or line extension utilizing the Compound outside the Field (a "New
      Development"), Licensor shall provide Licensee a right of first negotiation
      (the
      "Right of First Negotiation") as follows: (i) Licensor shall describe the New
      Development in writing in reasonable detail, and such description shall be
      protected as Proprietary Information under this Agreement (a "Confidential
      Disclosure"); (ii) Licensor shall provide the Confidential Disclosure to
      Licensee; and (iii) during the period commencing upon Licensee's receipt of
      the
      Confidential Disclosure and expiring ninety (90) days thereafter (the
      "Discussion Period"), the parties shall discuss in good faith a license and
      commercialization agreement with respect to the New Development. If
      the parties do not reach agreement during the Discussion Period, then the Right
      of First Negotiation shall expire, and Licensor shall be free to exploit the
      New
      Development on its own, or to market the New Development to others.

     

    
      
        
        

      

      
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    (b)
      Right
      of First Refusal
      In the event Licensor receives an offer from any third party to license or
      commercialize a New Development (an "Outside Offer"), Licensee shall enjoy
      a
      right of first refusal (the "Right of First Refusal") as follows: Licensor
      shall
      not accept any Outside Offer unless (i) Licensor has first provided the Outside
      Offer in writing to Licensee; and (ii) Licensee is provided a period of thirty
      (30) days from its receipt of the Outside Offer to evaluate the Outside Offer
      (the "Evaluation Period"). If Licensor receives from Licensee before expiration
      of the Evaluation Period a written offer that meets each of the terms of the
      Outside Offer or is more advantageous to Licensor than the Outside Offer (a
      "Qualifying Licensee Offer"), then Licensor shall either (a) reject the Outside
      Offer, or (b) accept the Qualifying Licensee Offer. Licensor shall not be
      obligated to accept the Qualifying Licensee Offer (in which event, the Licensor
      shall not accept the Outside Offer). If a Qualifying Licensee Offer is not
      received within the Evaluation Period, then the Right of First Refusal shall
      expire, and Licensor shall be free to accept the Outside Offer.

     

    7.8.2 For
      any indications or line extensions developed by Licensee utilizing the Compound
      outside the Field, Licensor shall have Right of First negotiation and Right
      of
      First Refusal similar to those available under Section 7.8.1 herein to obtain
      a
      license as follows:

     

    (a)
      Right
      of First Negotiation.
      If Licensee conceives of an indication or line extension utilizing the Compound
      outside the Field, Licensee shall provide Licensor a Right of First Negotiation
      as follows: (i) Licensee shall describe the New Development in writing in
      reasonable detail, and such description shall be protected as Confidential
      Disclosure under this Agreement; (ii) Licensee shall provide the Confidential
      Disclosure to Licensor; and (iii) during the period commencing upon Licensor's
      receipt of the Confidential Disclosure and expiring ninety (90) days thereafter,
      the parties shall discuss in good faith a license and commercialization
      agreement with respect to the New Development. If the parties do not reach
      agreement during the Discussion Period, then the Right of First Negotiation
      shall expire, and Licensee shall be free to exploit the New Development on
      its
      own, or to market the New Development to others.

     

    
      
        
        

      

      
        13

        
          

        

      

      
        
        

      

    

     

    (b)
      Right
      of First Refusal.
      In the event Licensee receives an Outside Offer to license or commercialize
      a
      New Development, Licensor shall enjoy a Right of First Refusal as follows:
      Licensee shall not accept any Outside Offer unless (i) Licensee has first
      provided the Outside Offer in writing to Licensor; and (ii) Licensor is provided
      a period of thirty (30) days from its receipt of the Outside Offer to evaluate
      the Outside Offer. If Licensee receives from Licensor before expiration of
      the
      Evaluation Period a written offer that meets each of the terms of the Outside
      Offer or is more advantageous to Licensee than the Outside Offer (the
      "Qualifying Licensor Offer"), then Licensee shall either (a) reject the Outside
      Offer, or (b) accept the Qualifying Licensor Offer. Licensee shall not be
      obligated to accept the Qualifying Licensor Offer (in which event, the Licensee
      shall not accept the Outside Offer). If a Qualifying Licensor Offer is not
      received within the Evaluation Period, then the Right of First Refusal shall
      expire, and Licensee shall be free to accept the Outside Offer.

     

    7.9
      Progress
      Reports.
      On a quarterly basis, and within thirty (30) days of the close of each quarter,
      Licensee shall provide to Licensor a written report of Licensee's progress
      and
      activities in meeting Licensee's obligations under Sections 7.1 and 7.2 (each
      a
      "Progress Report"). Progress Reports shall be in writing, and shall set forth,
      in reasonable detail, relevant information including (i) the status of clinical
      development programs for any Product; (ii) the status of regulatory approvals
      in
      the US and in other jurisdictions within the Territory concerning Products;
      and
      (iii) the status of other development activities regarding Products. Licensee
      shall promptly supplement or clarify such Progress Reports, upon Licensor's
      reasonable request.

     

    ARTICLE
      8. PATENT PROSECUTION

     

    8.1
        Patent
      Prosecution and Maintenance. 

     

    8.1.1 Patent
      Rights.
      Licensor shall use reasonable efforts to prosecute the patent applications
      included in the Patent Rights, (subject to the provisions of Section 8.1.2(d)
      to
      obtain patents thereon, to conduct any interference, re-examination, reissue
      and
      opposition proceedings, and to maintain patents included in the Patent Rights
      in
      effect during the term of this Agreement using outside patent counsel acceptable
      to Licensor. Licensor shall be solely responsible for all costs and expense
      relating to such patent applications and patents. Licensor shall regularly
      consult with Licensee and shall keep Licensee advised of the status of all
      patent applications and patents relating to the Patent Rights by providing
      Licensee with copies of such patent applications and patents and copies of
      all
      patent office correspondence relating thereto including any office actions
      received by Licensor and responses or other papers filed by Licensor. Licensor
      specifically agrees to provide Licensee with copies of patent office
      correspondence in sufficient time for Licensee to review and comment on such
      correspondence and submit to Licensor any proposed response thereto. Licensor
      further agrees to provide Licensee with sufficient time and opportunity, but
      in
      no event less than ten (10) days, to review, comment and consult on all proposed
      responses to patent office correspondence relating to such patent applications
      and patents. Licensee agrees that all final decisions regarding the preparation
      and prosecution of such patent applications and patents, reissues,
      reexaminations, interferences and oppositions relating thereto shall be made
      by
      Licensor after consultation with Licensee. Notwithstanding the foregoing,
      Licensor shall have the right in its sole discretion after consultation with
      Licensee, to discontinue the prosecution of any such patent applications or
      the
      maintenance of any such patents, and Licensee shall have the right to assume
      responsibility for the prosecution of such patent applications or the
      maintenance of such patents at its own expense. No royalties shall be payable
      by
      Licensee to Licensor under Section 5.1 hereof in respect of any such patent
      applications or patents being prosecuted or maintained by Licensee until
      Licensee has been reimbursed for its out-of-pocket costs of prosecuting and
      maintaining such patent applications or patents. If Licensor elects
      not to prosecute,
      and Licensee elects not to assume,
      any such patent applications or not to maintain any such patents
      in any country within the Territory,
      Licensee’s license rights and its obligations under this Agreement, with respect
      to such patent applications and patents in
      such country shall
      terminate,
      without affecting its license rights
      and other obligations to pay
      with respect to any other patent applications or patents included in the Patent
      Rights.

     

    
      
        
        

      

      
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    8.1.2 Improvements.
      

     

    (a) Each
      party shall notify the other party promptly of any sole or joint inventions
      directed to Improvements under such party's control. Licensee shall own all
      right, title and interest in and to Licensee solely invented Improvements and
      Licensor shall own all right, title and interest in and to Licensor solely
      invented Improvements. Patent applications and patents directed to jointly
      invented Improvements shall be jointly assigned to and owned by Licensee and
      Licensor, and the rights of the parties with respect thereto shall be determined
      according to the laws of the countries in which such patent applications and
      patents are held. 

     

    (b) During
      the term of this Agreement, for patent applications and patents relating to
      Improvements invented solely by Licensor, the provisions of Section 8.1.1 shall
      apply. 

     

    (c) Following
      expiration or termination of this Agreement, Licensor shall be solely
      responsible, at its sole discretion and expense, for preparing, filing,
      prosecuting and maintaining in such countries where it deems appropriate, patent
      applications and patents relating to Improvements invented solely by Licensor
      and for conducting interference, re-examination, reissue and opposition
      proceedings relating to such patent applications and patents.

     

    (d) During
      the term of this Agreement, Licensee shall be responsible, in its sole
      discretion and expense, for preparing, filing, prosecuting and maintaining
      in
      such countries where it deems appropriate, patent applications and patents
      relating to Improvements invented solely by Licensee or jointly by Licensee
      and
      Licensor. Notwithstanding the foregoing, if Licensee elects (after consultation
      with Licensor) not to prosecute, or to discontinue the prosecution of any patent
      applications concerning joint inventions, or to discontinue the maintenance
      of
      any patents concerning joint inventions, then (i) Licensor shall have the right
      to assume the full responsibility for the prosecution of such patent
      applications or the maintenance of such patents at its own costs expense, (ii)
      Licensee shall assign such patents and patent applications to Licensor, and
      (iii) such patents and patent applications shall no longer be subject to this
      Agreement.

     

    
      
        
        

      

      
        15

        
          

        

      

      
        
        

      

    

     

    (e) Following
      expiration or termination of this Agreement, Licensee shall be solely
      responsible, in its sole discretion and expense, for preparing, filing,
      prosecuting and maintaining in such countries where it deems appropriate, patent
      applications and patents relating to Improvements invented solely by Licensee
      and for conducting interference, re-examination, reissue and opposition
      proceedings relating to such patent applications and patents. 

     

    (f) Following
      expiration or termination of this Agreement, the parties shall be jointly
      responsible for preparing, filing, prosecuting and maintaining in such countries
      where the parties jointly agree, patent applications and patents relating to
      improvements jointly invented by the parties and for conducting interference,
      re-examination, reissue and opposition proceedings relating to such patent
      applications and patents. The parties shall jointly bear all costs relating
      thereto. If one party elects to discontinue the prosecution of any patent
      applications and patents filed pursuant to this Section 8.1.2(f), or not to
      conduct any further activities with respect to such patent applications or
      patents, the party electing to discontinue any such activities shall assign
      to
      the other party all right, title and interest in and to such patents or patent
      applications. The party electing to continue such activities shall be solely
      responsible for all costs relating to such activities.

     

    ARTICLE
      9. INFRINGEMENT

     

    9.1  Infringement
      by a Third Party.
      In the event that either party becomes aware that a Compound or a Product being
      made, used or sold by a Third Party infringes the Patent Rights licensed
      hereunder, such party shall promptly advise the other party of all known facts
      and circumstances relating thereto.
      Licensor shall have the first right to enforce at Licensor’s sole expense the
      Patent Rights licensed under this Agreement against infringement by third
      parties. Licensee shall reasonably cooperate in any such enforcement and, if
      necessary, join as a party therein, at the expense of Licensor. Licensor shall
      have the right to retain 100% of the proceeds of any such enforcement action.
      In
      the event that Licensor does not file suit against or commence settlement
      negotiations with a substantial infringer of the Patent Rights within six (6)
      months after receipt of and a written demand from Licensee that Licensor bring
      suit, then Licensee shall have the right to enforce at its own expense any
      patent licensed hereunder on behalf of itself and Licensor, Licensor shall
      reasonably cooperate with Licensee, at the expense of Licensee. In this case,
      Licensee shall have the right to retain 100% of the proceeds of any such
      enforcement action. 

     

    9.2
       Infringement
      by Licensee.
      In the event that it is determined by any court of competent jurisdiction that
      the manufacture, use or sale of any Product by Licensee or its Sublicensees
      in
      accordance with the terms and conditions of this Agreement infringes, or
      Licensee and Licensor reasonably determine and agree that the manufacture,
      use
      or sale of such Product is likely to infringe, an additional Third Party patent
      or related intellectual property right in any country in the Territory, Licensee
      shall in consultation with Licensor use its reasonable best efforts to: (i)
      procure at Licensee’s expense a license from such Third Party authorizing
      Licensee to continue to manufacture, use or sell such Product; or (ii) modify
      such Product or its manufacture so as to render it non-infringing. In the event
      that neither of the foregoing alternatives is reasonably available or
      commercially feasible, Licensee may at its option (i) either cease the
      manufacture, use and sale of such Product for so long as and to the extent
      that
      such activities are infringing the relevant Third Party patents, in which case
      the obligation of Licensee hereunder to pay royalties shall also cease, or
      (ii)
      terminate the rights and licenses granted solely with respect to a country
      or
      countries within the Territory in which the infringement of Third Party patents
      has occurred or is likely to occur, in which case the obligation of Licensee
      hereunder to pay royalties shall also terminate with respect to that country
      or
      countries within the Territory.

     

    
      
        
        

      

      
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    ARTICLE
      10. INDEMNIFICATION

     

    10.1
        Indemnification
      by Licensee.
      Licensee agrees to indemnify and hold Licensor, its directors, officers,
      employees and agents harmless from and against any liabilities or damages or
      expenses in connection therewith (including reasonable attorneys' fees and
      costs
      and other expenses of litigation) resulting from (i)
      any willful misrepresentation of a material fact or breach of warranty under
      this Agreement, (ii) claims by Third Parties arising out of Licensee's or its
      Sublicensees' manufacture, use, sale or testing of Product; and (iii) the
      enforcement by Licensor of its indemnification rights against Licensee under
      clause (ii) of this Section 10.1. 

     

    10.2 Indemnification
      by Licensor.
      Licensor hereby agrees to indemnify and hold Licensee and its officers,
      directors, employees and agents harmless from and against any liabilities or
      damages or expenses in connection therewith (including reasonable attorneys'
      fees and costs and other expenses of litigation) resulting from any willful
      misrepresentation of a material fact or breach of warranty under this Agreement
      and the enforcement by Licensee of its indemnification rights under this Section
      10.2. 

     

    10.3
       Indemnification
      Procedures.
      Each indemnified party shall promptly notify the indemnifying party in writing
      of any action, claim or liability in respect of which the indemnified party
      intends to claim indemnification from the indemnifying party. The indemnified
      party shall permit the indemnifying party, at its discretion, to settle any
      such
      action, claim or liability, and agrees to the complete control of such defense
      or settlement by the indemnifying party, provided however, that such settlement
      does not adversely affect the rights of the indemnified party hereunder or
      impose any obligations on the indemnified party in addition to those set forth
      herein in order for it to exercise such rights. No such action, claim or
      liability shall be settled by the indemnified party without the prior written
      consent of the indemnifying party, which consent shall not be unreasonably
      withheld or delayed, and the indemnifying party shall not be responsible for
      any
      legal fees or other costs incurred by the indemnified party other than as
      provided herein. The indemnified party and its directors, officers, employees
      and agents shall cooperate fully with the indemnifying party and its legal
      representatives in the investigation and defense of any action, claim or
      liability covered by this indemnification, and shall have the right, but not
      the
      obligation, to be represented by counsel of their own selection and at their
      own
      expense.

     

    
      
        
        

      

      
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    10.4 Limitation
      of Liability.
      Notwithstanding anything to the contrary herein, neither party shall be liable
      to the other party for any indirect, incidental or consequential damages arising
      out of any terms or conditions in this Agreement or with respect to the
      performance hereof.

     

    10.5
       Survival
      of Representations and Warranties. The representations and warranties contained
      in this Agreement shall survive the expiration or termination of this Agreement
      and shall remain in full force and effect. 

     

    ARTICLE
      11. CONFIDENTIALITY

     

    11.1
       Treatment
      of Proprietary Information.
      Except as otherwise provided in this Article 11, during the term of this
      Agreement and for a period of five (5) years following expiration or termination
      thereof, a party (the "Receiving Party") will retain in confidence and use
      only
      for purposes of this Agreement Proprietary Information supplied by or on behalf
      of the other party (the "Disclosing Party"). For purposes of this Article 11,
      all such Proprietary Information which a Receiving Party is obligated to retain
      in confidence shall be disclosed in written form and marked "Confidential"
      or
      with similar designation, or if originally disclosed visually or orally, reduced
      to such written form within thirty (30) days of such original
      disclosure.

     

    11.2
      Right
      to Disclose.
      To the extent it is reasonably necessary or appropriate to fulfill its
      obligations or exercise its rights under this Agreement or any rights which
      survive termination or expiration hereof, a Receiving Party may disclose
      Proprietary Information to its Affiliates, Sublicensees, consultants, agents,
      outside contractors and clinical investigators (collectively the
“Representatives”) on condition that such Representatives agree (i) to keep the
      Proprietary Information confidential for a least the same time periods and
      to
      the same extent as such party is required to keep the Proprietary Information
      confidential and (ii) to use the Proprietary Information only for such purposes
      as the Receiving Party is entitled to use the Proprietary Information. Each
      party warrants that each of its Representatives to whom any Proprietary
      Information is disclosed shall previously have been informed of the confidential
      nature of the Proprietary Information and shall have agreed to be bound by
      the
      terms and conditions of confidentiality as set forth in this Agreement. The
      Receiving Party shall ensure that the Proprietary Information provided by the
      Disclosing Party shall not be used or disclosed by such Representatives except
      as permitted by this Agreement. The Receiving Party shall stand responsible
      for
      any breach by its Representatives of the confidentiality provisions set forth
      in
      this Agreement.

     

    
      
        
        

      

      
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    11.3 Release
      From Restrictions.
      The obligation not to disclose Proprietary Information shall not apply to any
      part of such Proprietary Information which:

     

    (i)
      is or becomes patented, published or otherwise part of the public domain other
      than by the unauthorized acts of the Receiving Party or its Affiliates or
      Sublicensees in contravention of this Agreement; or 

     

    (ii)
      is disclosed to the Receiving Party by a Third Party which did not obtain such
      Proprietary Information directly or indirectly from the Disclosing Party; or
      

     

    (iii)
      prior to disclosure under this Agreement, was already in the possession of
      the
      Receiving Party as evidenced by its written records, provided such Proprietary
      Information was not obtained, directly or indirectly, from the Disclosing Party;
      or    

     

    (iv)
      is developed by the Receiving Party independent of Proprietary Information
      received from the Disclosing Party as evidenced by its written
      records.

     

    11.4.
       Public
      Domain.
      For the purpose of this Agreement, specific information disclosed as part of
      the
      Proprietary Information shall not be deemed to be in the public domain or in
      the
      prior possession of the Receiving Party merely because it is embraced by more
      general information in the public domain or by more general information in
      the
      prior possession of the Receiving Party.

     

    11.5
       Ownership
      of Proprietary Information.
      Except as otherwise agreed to hereunder, all Proprietary Information disclosed
      by the Disclosing Party shall remain the property of the Disclosing Party.
      Upon
      the written request of the Disclosing Party (i) all tangible Proprietary
      Information provided by the Disclosing Party (including, but not limited to
      all
      copies thereof and all unused samples of materials provided by the Disclosing
      Party) except for Proprietary Information consisting of analyses, studies and
      other documents prepared by or for the benefit of the Receiving Party shall
      be
      promptly returned to the Disclosing Party, and (ii) all portions of such
      analyses, studies and other documents not prepared by or for the benefit of
      the
      Receiving Party (including all copies thereof) which are within the definition
      of Proprietary Information shall be destroyed, and the Receiving Party shall
      certify such destruction in writing to the Disclosing Party. Notwithstanding
      the
      foregoing, the Receiving Party may retain one copy of the Proprietary
      Information of the Disclosing Party in its legal department for the sole purpose
      of determining its obligations hereunder.

     

    11.6
       Legal
      Disclosure.
      The Receiving Party may disclose the Proprietary Information of the Disclosing
      Party to the extent reasonably necessary in prosecuting or defending litigation,
      complying with applicable laws, governmental regulations or court order, or
      otherwise submitting required information to tax or other governmental
      authorities. If the Receiving Party intends to so disclose any such Proprietary
      Information, the Receiving Party shall provide the Disclosing Party prompt
      prior
      notice of such fact so that the Disclosing Party may seek to obtain a protective
      order or other appropriate remedy concerning any disclosure of such Proprietary
      Information. The Receiving Party will reasonably cooperate with the Disclosing
      Party in connection with the Disclosing Party’s efforts to obtain any such order
      or other remedy. If any such order or other remedy does not fully preclude
      the
      disclosure of such Proprietary Information, the Receiving Party will make such
      disclosure only to the extent that such disclosure is legally required and
      will
      use its reasonable efforts to have confidential treatment accorded to the
      disclosed Proprietary Information.

     

    
      
        
        

      

      
        19

        
          

        

      

      
        
        

      

    

     

    11.7
       No
      Title.
      Except as otherwise expressly set forth in this Agreement, nothing herein shall
      be construed as giving the Receiving Party any right, title and interest in
      and
      to the Proprietary Information of the Disclosing Party.

     

    11.8
       Permitted
      Disclosures.
      

     

    11.8.1 Disclosure
      by Licensee.
      Notwithstanding the foregoing, subject to review and comment by Licensor,
      Licensee may disclose Licensor Proprietary Information to the extent such
      disclosure is reasonably necessary for (a) the development of the Compound
      or
      the Product, (b) the filing of applications for Registration, (c) the
      commercialization of the Compound or the Product, or (d) the filing or
      prosecution of a patent applications and patents relating to Improvements
      invented solely by Licensee or jointly by Licensee and Licensor. 

     

    11.8.2 Disclosure
      by Licensor.
      Notwithstanding the foregoing, subject to review and comment by Licensee,
      Licensor may disclose Licensee Proprietary Information to the extent such
      disclosure is reasonably necessary for the filing or prosecution of patent
      applications and patents relating to Improvements invented solely by Licensor.
      

     

    11.9
       Publications.
      Neither Party shall submit or present any written or oral publication, any
      manuscript, abstract or the like which includes data or other information
      related to the Compound or the Products or the Proprietary Information of the
      other Party without first obtaining the prior written consent of the other
      Party.

     

    ARTICLE
      12. TERM AND TERMINATION

     

    12.1
       Term.
      Unless terminated sooner as provided herein, this Agreement shall continue
      in
      full force and effect from the Effective Date until the expiration of Licensee's
      obligation to pay royalties hereunder. Upon expiration or termination of this
      Agreement with respect to one or more countries of the Territory, the rights
      and
      obligation of the parties with respect to each such country or countries shall
      cease, except as follows:

     

    (i)
      upon expiration or termination by either party for any reason, the rights and
      obligations under Articles 2, 6, 10, 11, 12 and 22 and the applicable provisions
      of Section 8.1.2; 

     

    (ii)
      expiration or termination of this Agreement shall not relieve either party
      of
      any obligations which accrued to that party prior to such expiration or
      termination for any reason; and

     

    (iii)
      any cause of action or remedy for breach shall survive the expiration or
      termination of this Agreement.

     

    
      
        
        

      

      
        20

        
          

        

      

      
        
        

      

    

    *****Confidential
      material redacted and filed
      separately with the Commission.

     

    12.2
       Termination
      by Licensee. 

     

    12.2.1 Licensee
      may terminate this Agreement (i) in its entirety or (ii) with respect to one
      or
      more countries of the Territory without affecting the Agreement or the licenses
      granted hereunder in any other country of the Territory, without cause at any
      time upon at least ninety (90) days prior written notice to
      Licensor.

     

    12.2.2 Licensee
      may terminate this Agreement upon or after the breach of any material provision
      of this Agreement by Licensor if such breach is not cured within ninety (90)
      days after Licensee gives Licensor written notice thereof.

     

    12.2.3
      Licensee may terminate this Agreement in its entirety for cause upon at least
      ninety (90) days prior written notice to Licensor 

     

    upon
      or after the bankruptcy, insolvency, dissolution or winding up of Licensor
      other
      than for the purpose of reconstruction or amalgamation.

     

    12.3
       Termination
      by Licensor.
      

     

    12.3.1 Licensor
      may terminate this Agreement in its entirety for cause at any time upon at
      least
      ninety (90) days prior written notice to Licensee upon the occurrence of any
      of
      the following:

     

    (a)
      upon or after the breach of any material provision of this Agreement by Licensee
      if such breach is not cured within ninety (90) days after Licensor gives
      Licensee written notice thereof;

     

    (b)
      upon a Payment Default; or.

     

    (c)
      upon or after the bankruptcy, insolvency, dissolution or winding up of Licensee
      other than for the purpose of reconstruction or amalgamation; or

     

    12.4
       Development
      Data
      and Know-How.
      

     

    12.4.1 
      In the event of termination of this Agreement with respect to all countries
      in
      the Territory, Licensee will, promptly transfer and hand over to Licensor all
      Licensor Development Data and
      Licensor Know-How provided
      to Licensee hereunder. Each party will return to the other party
      all copies of the Proprietary Information supplied by one party to the other
      party hereunder, except that one copy of such Proprietary Information may be
      retained by each party for archival purposes only. 

     

    12.4.2 Upon
      termination of this Agreement or the license rights granted hereunder by either
      party for any reason with respect to one or all countries
      of the Territory (other than a termination by Licensee for an uncured breach
      or
      default by Licensor), Licensee will grant Licensor access to (and allow Licensor
      to obtain copies of) all Licensee Development Data
      and Licensee Know-How.
      Licensor shall have the right to disclose to a Third Party all such Licensee
      Development Data
      and Licensee Know-How
      in connection with Licensor’s effort to license to such Third Party the right to
      manufacture and sell a Product in those countries where termination of
      Licensee’s rights has occurred. Such use or disclosure shall be subject to the
      Licensee’s rights in countries where termination has not occurred and to the
      right, title and interest in such Licensee Development Data and Licensee
      Know-How which shall remain vested in Licensee. The Third Party shall not be
      entitled to sublicense, assign or transfer any of the rights granted to it
      by
      Licensor except to an Affiliate of such Third Party. Licensee
      agrees to cooperate with and provide reasonable assistance to Licensor in its
      effort to license to a Third Party the use of such Licensee Development
      Data.
      and Licensee Know-How. In
      consideration thereof, Licensor shall
      pay to Licensee a royalty of ***** on Net Sales of Product sold by Licensor
      or
      such Third Party
      for a period of ***** from
      the commencement of
      the sale of the
      Product.
      Any
      license granted by Licensor to such Third Party that bears a Licensee Royalty
      (a
      "Covered License") shall be consistent with the terms and conditions of this
      Agreement and shall include without limitation, provisions necessary to ensure
      that Licensor or such Third Party comply with royalty reporting and audit
      requirements, and confidentiality. Any act or omission by such Third Party
      under
      a Covered License which would have constituted a breach of this Agreement had
      it
      been the act or omission of Licensor, shall be deemed to constitute a breach
      of
      this Agreement by Licensor. Licensor shall advise Licensee without delay of
      any
      breach by such Third Party and Licensor shall exercise without delay its rights
      with respect to such breach against such Third Party.

     

    
      
        
        

      

      
        21

        
          

        

      

      
        
        

      

    

     

    12.5
       Disposition
      of Product.
      Upon termination of this Agreement with respect to any country, Licensee shall
      provide Licensor a written inventory of all Product (in the form of raw
      material, work-in-progress and finished goods) in its and its Sublicensees'
      possession in such country, and shall have the right to dispose of such Product
      within six (6) months thereafter, subject to fulfillment of the royalty
      obligations relating thereto.

     

    ARTICLE
      13. ASSIGNMENT

     

    This
      Agreement may not be assigned or otherwise transferred by either party without
      the written consent of the other party except that either party without such
      consent may assign or sell the license (i) in connection with the transfer
      or
      sale of all or substantially all of its business assets to a Third Party, or
      (ii) in the event of its merger or consolidation with another company, or (iii)
      to an Affiliate. Any purported assignment in violation of this clause shall
      be
      void. Any permitted assignee shall assume all the obligations of its assignor
      under this Agreement. No assignment shall relieve either party of its
      responsibility for the performance of any obligation that such party has accrued
      hereunder as of the date of assignment.

     

    ARTICLE
      14 PATENT MARKINGS

     

    Licensee
      agrees to mark all Products made, used or sold under the terms of this
      Agreement, or their containers, in accordance with applicable patent marking
      laws.

     

    ARTICLE
      15. REGISTRATION OF LICENSES

     

    Licensee
      agrees to register or give required notice concerning this Agreement, through
      itself or through a Sublicensee, in each country where there exists an
      obligation under law to so register or give notice, to pay all costs and legal
      fees connected therewith, and to otherwise comply with all national laws
      applicable to this Agreement. Upon request by Licensee, Licensor agrees to
      promptly execute any "short form" licenses in a form submitted to it by Licensee
      in order to effectuate the foregoing registration in each such
      country.

     

    
      
        
        

      

      
        22

        
          

        

      

      
        
        

      

    

     

    ARTICLE
      16. PATENT TERM EXTENSION

     

    Licensee
      agrees, as exclusive Licensee, to apply for and to exercise due diligence in
      obtaining an extension of the term of any patent included within the Patent
      Rights under the applicable laws of any country where such extensions are
      available, including, but not limited to, the Drug Price Competition and Patent
      Term Restoration Act of 1984 in the United States. Licensor agrees to execute
      such documents and take such additional actions as Licensee may reasonably
      request in connection therewith. Each party shall bear its own expenses in
      connection with the application for patent term extensions.

     

    ARTICLE
      17. FORCE MAJEURE

     

    Neither
      party shall be held liable or responsible to the other party nor be deemed
      to
      have defaulted under or breached this Agreement for failure or delay in
      fulfilling or performing any term of this Agreement, other than an obligation
      to
      make a payment, when such failure or delay is caused by or results from fires,
      floods, embargoes, government regulations, prohibitions or interventions, wars,
      acts of war, terrorism, insurrections, riots, civil disobedience, strikes,
      lockouts, acts of God, or any other cause beyond the reasonable control of
      the
      affected party.

     

    ARTICLE
      18. NEGATION OF AGENCY.

     

    Nothing
      herein contained shall be deemed to create an agency, joint venture,
      amalgamation, partnership, or similar relationship between Licensee and
      Licensor. The relationship between the parties established by this Agreement
      is
      that of independent contractors. Neither party shall have the power to bind,
      obligate, incur any debts or make any commitments for the other party except
      to
      the extent, if at all, specifically provided herein.

     

    ARTICLE
      19. PUBLICITY

     

    Each
      party shall give notice to the other party prior to issuing any press release
      relating to this Agreement within due time to allow for reasonable
      consideration. The party issuing the press release shall give due consideration
      and weight to any comments or concerns raised by the other party.
      Notwithstanding the foregoing, neither party shall issue a press release
      announcing the execution of this Agreement outside of a joint press release
      which will be prepared jointly by the parties.

     

    
      
        
        

      

      
        23

        
          

        

      

      
        
        

      

    

     

    ARTICLE
      20. FILING OF THE AGREEMENT

     

    To
      the extent, if any, that a party concludes in good faith that it is required
      to
      file this Agreement or a notification thereof with any governmental authority,
      including without limitation the U.S. Securities and Exchange Commission in
      accordance with applicable laws and regulations, such party may do so, subject
      to the confidentiality obligations set forth herein, and the other party shall
      cooperate in such filing or notification and shall execute all documents
      reasonably required in connection therewith at the, expense of the requesting
      party. The parties shall promptly inform each other as to the activities or
      inquiries of any such governmental authority relating to this Agreement, and
      shall cooperate, in responding to any request for further information therefrom
      at the expense of the requesting party.

     

    ARTICLE
      21. SEVERABILITY

     

    Each
      party hereby expressly agrees and contracts that it is not the intention of
      either party to violate any public policy, statutory or common laws, rules,
      regulations, treaty or decision of any government agency or executive body
      thereof of any country or community or association of countries. If any word,
      sentence, paragraph, clause or combination thereof in this Agreement is found
      by
      a court or executive body with judicial powers having jurisdiction over this
      Agreement or any of the parties hereto in a final unappealable order to be
      in
      violation of any such provisions in any country or community or association
      of
      countries, such word, sentence, paragraph, clause or combination thereof shall
      be inoperative in such country or community or association of countries, and
      the
      parties will seek in good faith to amend this Agreement in order to cure such
      violation; the remainder of this Agreement shall in any event remain binding
      upon the parties hereto.

     

    ARTICLE
      22. NOTICES

     

    Any
      notices required or permitted to be given hereunder shall be in writing and
      shall be deemed to have been properly given if delivered in person, or if mailed
      by registered or certified mail (return receipt requested), postage prepaid,
      or
      by telex or facsimile or e-mail promptly confirmed by first class mail, to
      the
      addresses given below or such other addresses as may be designated in writing
      by
      the parties from time to time during the term of this Agreement. Any notice
      sent
      or by telex or facsimile or e-mail shall be effective when sent, and any notice
      sent by registered or certified mail shall be effective when
      mailed.

     

    In
      the case of Licensee:

     

    Keryx
      Biopharmaceuticals, Inc

    750
      Lexington Ave, 20th
      Floor

    New
      York, NY 10022

    Attn:
      Michael S. Weiss

    Chairman
      & CEO

    Email:
      msw@keryx.com

     

    
      
        
        

      

      
        24

        
          

        

      

      
        
        

      

    

     

    In
      the case of Licensor:

     

    Panion
      & BF Biotech, Inc.

    16F
      No. 3, Yuanqu Street, 

    Nangang
      District, 

    Taipei,
      Taiwan, ROC

    Attn:
      Michael Chiang 

     

    c/o:
         

    Holland
      & Knight LLP

    2099
      Pennsylvania Avenue

    Washington,
      D.C. 20006

    (202)
      955-3000

    Attn:
      Jane K. P. Tam, Esq.

     

    ARTICLE
      23. GOVERNING LAW

     

    This
      Agreement shall be governed by and construed in accordance with the laws of
      the
      State of New York, exclusive of choice-of-law rules.

     

    ARTICLE
      24. AFFILIATES

     

    Each
      party may perform its obligations hereunder personally or through one or more
      Affiliate and shall be responsible for the performance of such obligations,
      and
      any liabilities resulting from such performance. Neither party shall permit
      any
      of its Affiliates to commit any act (including any act of omission) which such
      party is prohibited hereunder from committing directly. 

     

    ARTICLE
      25. ENTIRE AGREEMENT

     

    This
      Agreement and the Exhibits hereto which are a part hereof, contain the entire
      understanding of the parties with respect to the subject matter hereof. All
      express or implied agreements and understanding, either oral or written,
      heretofore made are expressly merged in and made a part of this Agreement.
      The
      parties hereto may alter any of the provisions of this Agreement, but only
      by a
      written instrument duly executed by both parties hereto.

     

    
      
        
        

      

      
        25

        
          

        

      

      
        
        

      

    

     

    ARTICLE
      26. WAIVER

     

    The
      failure of a party to enforce at any time for any period any of the provisions
      hereof shall not be construed as a waiver of such provisions or of the right
      of
      such party thereafter to enforce each such provision.

     

    ARTICLE
      27. CAPTIONS

     

    The
      captions to the several Articles and Sections hereof are not a part of this
      Agreement, but are merely guides or labels to assist in location and reading
      the
      several Articles and Sections hereof.

     

    IN
      WITNESS HEREOF,
      the parties have executed this Agreement as of the Effective Date.

     

    
      	KERYX BIOPHARMACEUTICALS,
              INC.	 	PANION & BF BIOTECH
              INC. 
	 	
            	 	 	 
	          By:  
              	 /s/
              Michael S. Weiss	 	          By: 	 /s/ Michael
              Chiang
	 	Chairman
              & CEO	 	 	 


    

     

     

    
      
        
        

      

      26