**C** **onfidential
        Treatment Requested. Confidential portions of this document have
        been**
 **omitted
        and have been separately filed with the Commission.**




**Execution
      Version**




**LICENSE
      AGREEMENT**




**By
      and Between**




**PRESIDIO
      PHARMACEUTICALS, INC.**




**and**




**XTL
      BIOPHARMACEUTICALS LTD.**





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




TABLE
      OF
      CONTENTS


Page**Article
                  I**Definitions
              **2**Section 1.1
              “Additional
                  Third Party Licenses”
              2Section 1.2
              “Affiliate”
              2Section 1.3
              “Assigned
                  Contracts”
              2Section 1.4
              “Bankruptcy
                  Code”
              3Section 1.5
              “Commercialization”
                  or “Commercialize”
              3Section 1.6
              “Commercially
                  Reasonable Efforts”
              3Section 1.7
              “Competing
                  Product”
              3Section 1.8
              “Confidential
                  Information”
              3Section 1.9
              “Control”
                  or “Controlled”
              3Section 1.10
              “Cover”,
                  “Covering” or “Covered”
              3Section 1.11
              “Derivative
                  Compounds”
              3Section 1.12
              “Development”
                  or “Develop”
              4Section 1.13
              “EMEA”
              4Section 1.14
              “EU”
              4Section 1.15
              “FDA”
              4Section 1.16
              “Field”
              4Section 1.17
              “Fiscal
                  Year”
              4Section 1.18
              “HCV”
              4Section 1.19
              “HCV
                  Field”
              4Section 1.20
              “IND”
              4Section 1.21
              “Know-How”
              4Section 1.22
              “Licensed
                  Compounds”
              5Section 1.23
              “Licensed
                  Patent Rights”
              5Section 1.24
              “Licensed
                  Product”
              5Section 1.25
              “Licensed
                  Technology”
              5Section 1.26
              “Major
                  EU Countries”
              5Section 1.27
              “NDA”
              5Section 1.28
              “Net
                  Sales”
              5Section 1.29
              “NS5A”
              7Section 1.30
              “Party”
                  or “Parties”
              7Section 1.31
              “Pass-Through
                  Costs”
              7Section 1.32
              “Patent
                  Rights”
              7Section 1.33
              “Person”
              7Section 1.34
              “Phase
                  I Trial”
              7Section 1.35
              “Phase
                  II Trial”
              7Section 1.36
              “Phase
                  III Trial”
              7Section 1.37
              “Regulatory
                  Approval”
              7Section 1.38
              “Regulatory
                  Authority”
              7Section 1.39
              “Regulatory
                  Filings”
              7Section 1.40
              “Royalty
                  Term”
              8Section 1.41
              “Senior
                  Executives”
              8Section 1.42
              “Series
                  1 Compounds”
              8Section 1.43
              “Series
                  1 Licensed Products”
              8
  -i-
  **Confidential
          material omitted and filed separately with the
          Commission.**
  Section 1.44
              “Series
                  1 Patent Rights”
              8Section 1.45
              “Series
                  2-4 Compounds”
              8Section 1.46
              “Series
                  2-4 Licensed Products”
              8Section 1.47
              “Series
                  2-4 Patent Rights”
              8Section 1.48
              “Series
                  5-50 Compounds”
              8Section 1.49
              “Sublicense
                  Income”
              9Section 1.50
              “Successful
                  Completion”
              9Section 1.51
              “Territory”
              9Section 1.52
              “Third
                  Party”
              10Section 1.53
              “Valid
                  Claim”
              10Section 1.54
              “VivoQuest
                  Asset Purchase Agreement”
              10Section 1.55
              *****
              10Section 1.56
              “VivoQuest
                  License Agreement”
              10Section 1.57
              “VivoQuest
                  Licensed Patents”
              10Section 1.58
              Additional
                  Definitions
              10**Article
                  II**Grant of License; Assigned Contracts;
                  Exclusivity
              **11**Section 2.1
              License
                  Grant
              11Section 2.2
              Assigned
                  Contracts
              11Section 2.3
              Exclusivity
              11Section 2.4
              Retained
                  Rights; Other Limitations
              12Section 2.5
              Section
                  365(n) of the Bankruptcy Code
              12**Article
                  III**Technology Transfer
              **12**Section 3.1
              Technology
                  Transfer
              12Section 3.2
              Technology
                  Transfer Committee; Decision-Making Authority.
              13**Article
                  IV**Reports and Meetings; Diligence; Certain Regulatory and
                  Manufacturing Activities
              **13**Section 4.1
              Development
                  Reports; Meetings.
              13Section 4.2
              Commercially
                  Reasonable Efforts
              14Section 4.3
              Certain
                  Regulatory and Manufacturing Activities
              14**Article
                  V**Financial Provisions
              **14**Section 5.1
              License
                  Payment
              14Section 5.2
              Milestone
                  Payments for Series 1 Licensed Products
              14Section 5.3
              Royalties
              16Section 5.4
              Sublicense
                  Income for Series 1 Licensed Products
              16Section 5.5
              Reduction
                  for Lack of Patent Coverage.
              17Section 5.6
              Reduction
                  for Pass-Through Costs Under Assigned Contracts and Additional
                  Third Party
                  Licenses
              17Section 5.7
              Priority
                  of Reduction
              18Section 5.8
              Offset
                  for Payment of VivoQuest Pass-Through Costs
              18Section 5.9
              Reports
                  and Accounting.
              18Section 5.10
              Currency
                  and Method of Payments
              19Section 5.11
              United
                  States Dollars
              19Section 5.12
              Tax
                  Withholding
              19Section 5.13
              Late
                  Payments
              20Section 5.14
              Blocked
                  Payments
              20Section 5.15
              Costs
                  and Expenses
              20**Article
                  VI**Intellectual Property Protection and Related
                  Matters
              **20**Section 6.1
              Prosecution
                  and Maintenance of Licensed Patent Rights.
              20
  -ii-
  **Confidential
          material omitted and filed separately with the
          Commission.**
  Section 6.2
              Third
                  Party Infringement.
              21Section 6.3
              Recoveries
              22Section 6.4
              Claimed
                  Infringement
              22Section 6.5
              Patent
                  Invalidity Claim
              22Section 6.6
              Patent
                  Marking
              22Section 6.7
              Certain
                  Limitations
              22**Article
                  VII**Confidentiality
              **22**Section 7.1
              Confidential
                  Information
              22Section 7.2
              Employee,
                  Director, Consultant and Advisor Obligations
              23Section 7.3
              Publicity.
              23Section 7.4
              Term
              24**Article VIII**Representations and Warranties
              **24**Section 8.1
              Representations
                  of Authority
              24Section 8.2
              Consents
              24Section 8.3
              No
                  Conflict
              24Section 8.4
              Employee,
                  Director, Consultant and Advisor Obligations
              24Section 8.5
              Intellectual
                  Property
              24Section 8.6
              No
                  Warranties
              27**Article
                  IX**Term and Termination
              **27**Section 9.1
              Term
              27Section 9.2
              Termination
                  For Material Breach
              27Section 9.3
              Termination
                  for Convenience
              28Section 9.4
              Effect
                  of Material Breach or Patent Validity Challenge by XTL or its
                  Affiliates.
              28Section 9.5
              Effects
                  of Termination.
              29Section 9.6
              Survival
              30**Article
                  X**Dispute Resolution
              **31**Section 10.1
              Referral
                  to Senior Executives
              31Section 10.2
              Mediation
              31Section 10.3
              Arbitration.
              31Section 10.4
              No
                  Limitation
              32**Article
                  XI**Miscellaneous Provisions
              **32**Section 11.1
              Indemnification.
              32Section 11.2
              Governing
                  Law
              34Section 11.3
              Assignment
              34Section 11.4
              Entire
                  Agreement; Amendments
              34Section 11.5
              Notices
              34Section 11.6
              Force
                  Majeure
              35Section 11.7
              Independent
                  Contractors
              35Section 11.8
              No
                  Strict Construction
              35Section 11.9
              Headings
              36Section 11.10
              No
                  Implied Waivers; Rights Cumulative
              36Section 11.11
              Severability
              36Section 11.12
              Execution
                  in Counterparts
              36Section 11.13
              No
                  Third Party Beneficiaries
              36Section 11.14
              No
                  Consequential Damages
              36




-iii-




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




Exhibit
      A – Assigned Contracts


Exhibit
      B – VivoQuest Agreements


Exhibit
      C – Series 1, 2, 3 and 4 Compounds in XTL Database and Other
      Records


Exhibit
      D – Series 1 Patent Rights as of the Effective Date


Exhibit
      E – Series 2-4 Patent Rights as of the Effective Date


Exhibit
      F – Press Releases


Exhibit
      G – *****




-i-


**LICENSE
      AGREEMENT**




This
      License Agreement (this “ Agreement ”),
      dated
      the 19 th day of
      March, 2008 (the “ Effective
      Date ”),
      is by
      and between Presidio Pharmaceuticals, Inc., a Delaware corporation
      (“ PRESIDIO ”),
      and
      XTL Biopharmaceuticals Ltd., a public company limited by shares organized under
      the laws of Israel (“ XTL ”).




**INTRODUCTION**




1.  XTL
      owns
      or controls rights to Licensed Compounds, Licensed Patent Rights and Licensed
      Technology (each as hereinafter defined).




2.  PRESIDIO
      is in the business of discovering, developing and marketing pharmaceutical
      products.




3.  XTL
      and
      PRESIDIO are interested in establishing a licensing relationship pursuant to
      which XTL shall grant PRESIDIO certain rights and licenses to the Licensed
      Compounds, Licensed Patent Rights and Licensed Technology to develop and
      commercialize certain products.




NOW,
      THEREFORE, for good and valuable consideration, the receipt and sufficiency
      of
      which are hereby acknowledged, PRESIDIO and XTL agree as follows:




**Article
      I**


Definitions




When
      used
      in this Agreement, each of the following terms shall have the meanings set
      forth
      in this Article I:




Section
      1.1  “ Additional
      Third Party Licenses ” .
      Additional Third Party Licenses means licenses under any Patent Rights of a
      Third Party (other than Licensed Patent Rights licensed or sublicensed to
      PRESIDIO under the VivoQuest License Agreement or any Assigned Contracts) which
      PRESIDIO and/or any of its Affiliates or Third Party sublicensees reasonably
      determines are necessary for the Development and/or Commercialization of a
      Licensed Compound or Licensed Product for use in the Field in any country of
      the
      Territory.




Section
      1.2  “ Affiliate ” .
      Affiliate means, with respect to a Party, any Person that controls, is
      controlled by, or is under common control with such Party. For purposes of
      this
      Section 1.2, “control” shall refer to (a) in the case of a Person that is a
      corporate entity, direct or indirect ownership of fifty percent (50%) or more
      of
      the stock or shares having the right to vote for the election of directors
      of
      such Person, and (b) in the case of a Person that is not a corporate entity,
      the
      possession, directly or indirectly, of the power to direct, or cause the
      direction of, the management or policies of such Person, whether through the
      ownership of voting securities, by contract or otherwise.




Section
      1.3  “ Assigned
      Contracts ” .
      Assigned Contracts means the agreements listed on Exhibit
      A .




-2-


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




Section
      1.4  “ Bankruptcy
      Code ” .
      Bankruptcy Code means 11 U.S.C §§ 101-1330, as amended.




Section
      1.5  “ Commercialization”
      or “Commercialize ” .
      Commercialization or Commercialize means any activities directed to producing
      or
      manufacturing for commercial distribution; marketing, promoting, detailing
      or
      commercially distributing; importing, having imported, exporting or having
      exported for commercial distribution; or selling or offering to sell, a
      product.




Section
      1.6  “ Commercially
      Reasonable Efforts ” .
      Commercially Reasonable Efforts means the efforts normally used by a United
      States biotechnology or pharmaceutical company with resources similar to those
      of PRESIDIO to Develop or Commercialize a pharmaceutical product or compound
      owned by it or to which it has rights, taking into account its market potential
      and the stage in its development or product life, relevant issues of safety
      and
      efficacy, product profile and labeling, other medical and clinical
      considerations, difficulty in developing the product or compound,
      competitiveness of the marketplace for the applicable product(s) marketed or
      to
      be marketed, the proprietary position of the compound or product, the regulatory
      structure involved, the potential profitability of the applicable product(s)
      marketed or to be marketed, and other relevant factors affecting the cost,
      risk
      and timing of Development and the total potential reward to be obtained if
      a
      product is Commercialized. Such efforts and resources that are used by
      PRESIDIO’s Affiliates and Third Party sublicensees shall be attributed to
      PRESIDIO for purposes of this Agreement.




Section
      1.7  “ Competing
      Product ” .
      Competing Product means any prescription pharmaceutical product that is an
      *****.




Section
      1.8  “ Confidential
      Information ” .
      Confidential Information means all Know-How and other information (whether
      or
      not patentable) regarding a Party’s technology, products, business or
      objectives, that is disclosed by such Party to the other Party in the course
      of
      such Party’s performance of this Agreement.




Section
      1.9  “ Control”
      or “Controlled ” .
      Control
      or Controlled means, with respect to any intellectual property right or other
      intangible property, the possession by a Party or an Affiliate of a Party
      (whether by ownership or license, other than a license granted pursuant to
      this
      Agreement) of the ability to grant access to, or a license or sublicense of,
      such rights or property as contemplated under this Agreement.




Section
      1.10  “ Cover”,
      “Covering” or “Covered ” .
      Cover,
      Covering or Covered means, as to Patent Rights and a product, that, but for
      a
      license granted to a Party under a Valid Claim of such Patent Rights, the
      Development or Commercialization of such product would infringe such Valid
      Claim.




Section
      1.11  “ Derivative
      Compounds ” .
      Derivative Compounds means, with respect to any Licensed Compound, any compounds
      actually chemically derived, in one or more steps, by or on behalf of PRESIDIO,
      its Affiliates and/or Third Party sublicensees from such Licensed Compound, provided  that ,
      compounds derived by Third Party sublicensees or Third Party acquirers of
      PRESIDIO shall not constitute Derivative Compounds if such compounds are so
      derived (i) prior to the effective date of the grant by PRESIDIO of the
      sublicense to such sublicensee or the acquisition by such acquirer, as evidenced
      by contemporaneously prepared written records of such sublicensee or
      acquirer or (ii) without any use, direct or indirect, of
      (A) proprietary know-how disclosed to such Third Party in connection with
      the grant of the sublicense or the acquisition, or (B) Licensed Compounds
      (including Derivative Compounds) on which Development had previously been
      conducted by XTL or PRESIDIO, the results of which prior Development are
      identified to such Third Party in connection with the grant of the
      sublicense or the acquisition.




-3-




Section
      1.12  “ Development”
      or “Develop ” .
      Development or Develop means any research, discovery, and preclinical and
      clinical drug development activities, including without limitation test method
      development and stability testing, toxicology, animal efficacy studies,
      formulation, quality assurance/quality control development, statistical
      analysis, clinical studies, regulatory affairs, product approval and
      registration, chemical development and manufacturing development, packaging
      development and manufacturing and development documentation efforts in support
      of development activities anywhere in the world.




Section
      1.13  “ EMEA ” .
      EMEA
      means the European Agency for the Evaluation of Medical Products, or any
      successor agency thereof.




Section
      1.14  “ EU ” .
      EU
      means the European Union, as it may be constituted from time to
      time.




Section
      1.15  “ FDA ” .
      FDA
      means the United States Food and Drug Administration, or any successor agency
      thereof.




Section
      1.16  “ Field ” .
      Field
      means the prevention, treatment, palliation and/or control of any and all human
      diseases and conditions, including without limitation the HCV
      Field.




Section
      1.17  “ Fiscal
      Year ” .
      Fiscal
      Year means, with respect to a Party or any Third Party sublicensee of a Party,
      the fiscal year of such Party or Third Party sublicensee.




Section
      1.18  “ HCV ” .
      HCV
      means hepatitis C virus.




Section
      1.19  “ HCV
      Field ” .
      HCV
      Field means the prevention, treatment, palliation and/or control of any and
      all
      HCV indications.




Section
      1.20  “ IND ” .
      IND
      means an Investigational New Drug application filed with the FDA.




Section
      1.21  “ Know-How ” .
      Know-How means any know-how, expertise, discoveries, inventions, information,
      trade secrets, data or materials, whether or not patentable, proprietary or
      embodied in tangible form, including without limitation ideas, concepts,
      formulas, methods, procedures, designs, technologies, compositions, plans,
      applications, technical data, samples, biological or chemical materials,
      laboratory notebooks, preclinical or clinical data, databases, designs, assays,
      protocols, analytical systems, discovery tools, reports, Regulatory Filings
      and
      manufacturing documentation.




-4-




Section
      1.22  “ Licensed
      Compounds ” .
      Licensed Compounds means (a) the Series 1 Compounds, and (b) the Series 2-4
      Compounds.




Section
      1.23  “ Licensed
      Patent Rights ” .
      Licensed Patent Rights means (a) the Series 1 Patent Rights, (b) the Series
      2-4
      Patent Rights, and (c) any other Patent Rights Controlled by XTL or any of
      its
      Affiliates, as of the Effective Date and/or during the term of this Agreement,
      that Cover any Licensed Technology and/or the Development and/or
      Commercialization of any Licensed Compounds or Licensed Products.




Section
      1.24  “ Licensed
      Product ” .
      Licensed Product means any product that contains one or more Licensed Compounds
      as an active ingredient.




Section
      1.25  “ Licensed
      Technology ” .
      Licensed Technology means any Know-How Controlled by XTL or any of its
      Affiliates, as of the Effective Date and/or during the term of this Agreement,
      relating to the Development and/or Commercialization of Licensed Compounds
      or
      Licensed Products, and all intellectual property rights therein.




Section
      1.26  “ Major
      EU Countries ” .
      Major
      EU Countries means any of the United Kingdom, Germany, France, Italy and
      Spain.




Section
      1.27  “ NDA ” .
      NDA
      means an application submitted to a Regulatory Authority for marketing approval
      of a product, including without limitation a New Drug Application filed with
      the
      FDA and any foreign equivalent thereof.




Section
      1.28  “ Net
      Sales ” .
      Net
      Sales means, with respect to a Licensed Product, the gross amount invoiced
      by
      PRESIDIO and/or its Affiliates, or by Third Party sublicensees, as the case
      may
      be, in respect of sales of such Licensed Product to unrelated Third Parties,
      in
      each case less the following deductions:




(a)  Trade,
      cash and/or quantity discounts actually allowed and taken with respect to such
      sales;




(b)  Discounts
      paid under discount prescription programs and reductions for coupon and voucher
      programs;




(c)  Tariffs,
      duties, excises, sales taxes, value-added taxes and other taxes imposed upon
      and
      paid by PRESIDIO and/or one of its Affiliates, or by Third Party sublicensees,
      as the case may be, with respect to the use, sale or importation of the Licensed
      Product, to the extent that neither PRESIDIO nor any of its Affiliates is
      entitled to a rebate, refund or credit for such amounts;




(d)  Amounts
      repaid or credited by reason of rejections, defects, recalls or returns or
      because of chargebacks, refunds, rebates or retroactive price
      reductions;




(e)  Negotiated
      payments made to private sector and government third party payors (e.g., PBMs,
      HMOs and PPOs) and purchasers/providers (e.g., staff model HMOs, hospitals
      and
      clinics), regardless of the payment mechanism, including without limitation
      rebate, chargeback and credit mechanisms;




-5-


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




(f)  Freight,
      insurance and other transportation charges incurred by PRESIDIO and/or its
      Affiliates, or by Third Party sublicensees, as the case may be, in shipping
      a
      Licensed Product to Third Parties;




(g)  Sales
      commissions and inventory management fees paid to wholesalers and distributors
      to the extent allocable to Licensed Products;




(h)  Amounts
      that are written off as uncollectible and costs of collections; and




(i)  Gross
      amounts received in respect of sales for test marketing, sampling or promotional
      use, clinical trial purposes or compassionate or similar use.




Such
      amounts shall be determined from the books and records of PRESIDIO and/or its
      Affiliates, or Third Party sublicensees, as the case may be, maintained in
      accordance with generally accepted accounting principles applicable within
      a
      particular country, consistently applied, including periodic adjustments to
      reflect amounts actually incurred.




In
      the
      event the Licensed Product is sold as part of a Combination Product (as defined
      below), the Net Sales from the Combination Product, for the purposes of
      determining royalty payments, shall be determined on a country-by-country basis
      by multiplying the Net Sales (as determined above) of the Combination Product
      in
      each country, during the applicable royalty reporting period, by the fraction
      A/(A+B), where A is the average net selling price of the Licensed Product when
      sold separately in finished form in such country and B is the average net
      selling price of the other active ingredient(s) included in the Combination
      Product when sold separately in finished form in such country, in each case
      during the applicable royalty reporting period or, if sales of both the Licensed
      Product and the other active ingredient(s) did not occur in such country in
      such
      period, then in the most recent royalty reporting period in which sales of
      both
      occurred in such country. In the event that such average net selling price
      cannot be determined for both the Licensed Product and all other active
      ingredient(s) included in such Combination Product for a country, Net Sales
      for
      the purposes of determining royalty payments shall be calculated by multiplying
      the Net Sales of the Combination Product in such country by the fraction of
      C/(C+D) where C is the fair market value of the Licensed Product and D is the
      fair market value of all other active ingredient(s) included in the Combination
      Product. In such event, PRESIDIO shall in good faith make a determination of
      the
      respective fair market values of the Licensed Product and all other active
      ingredient(s) included in the Combination Product, and shall notify XTL of
      such
      determination and provide XTL with data to support such determination. XTL
      shall
      have the right to review such determination of fair market values and, if XTL
      disagrees with such determination, to notify PRESIDIO of such disagreement
      within ***** days after PRESIDIO notifies XTL of such determination. If XTL
      notifies PRESIDIO that XTL disagrees with such determination within such *****
      day period and if thereafter the Parties are unable to agree in good faith
      as to
      such respective fair market values, then such matter shall be resolved as
      provided in Article X. If XTL does not notify PRESIDIO that XTL disagrees with
      such determination within such ***** day period, such determination shall be
      conclusive and binding on the Parties.




As
      used
      above, the term “ Combination
      Product ”
means
      any pharmaceutical product that includes both (x) a Licensed Product and (y)
      other active ingredient(s).




-6-




Section
      1.29  “ NS5A ” .
      NS5A
      means the HCV non-structural protein 5A, including without limitation partial
      and full-length proteins thereof.




Section
      1.30  “ Party”
      or “Parties ” .
      Party
      means PRESIDIO or XTL; Parties means PRESIDIO and XTL.




Section
      1.31  “ Pass-Through
      Costs ” .
      Pass-Through Costs means amounts payable to Third Parties pursuant to (a) the
      Assigned Contracts attached hereto as Exhibit
      A ,
      (b) the
      VivoQuest License Agreement attached hereto as Exhibit
      B ,
      and/or
      (c) Additional Third Party Licenses, including without limitation upfront
      payments or similar acquisition costs to obtain such licenses; in the case
      of
      each of the foregoing clauses (a), (b) and (c), with respect to the Development
      and/or Commercialization of Licensed Compounds or Licensed
      Products.




Section
      1.32  “ Patent
      Rights ” .
      Patent
      Rights means the rights and interest in and to all issued patents and pending
      patent applications in any country in the Territory, including without
      limitation all utility models, utility model applications, provisionals,
      divisionals, substitutions, continuations, continuations-in-part, continuing
      prosecution applications, patents of addition, requests for continued
      examination, reexaminations, supplementary protection certificates, extensions,
      registrations or confirmation patents, and reissues thereof.




Section
      1.33  “ Person ” .
      Person
      means any natural person or any corporation, company, partnership, joint
      venture, firm or other entity, including without limitation a
      Party.




Section
      1.34  “ Phase
      I Trial ” .
      Phase I
      Trial means a clinical study of a Licensed Product in human volunteers or
      patients with the endpoint of determining initial tolerance, toxicity, safety
      and/or pharmacokinetic information.




Section
      1.35  “ Phase
      II Trial ” .
      Phase
      II Trial means a dose exploration, dose response, duration of effect,
      kinetic/dynamic relationship and preliminary efficacy and safety
      clinical study of a Licensed Product in patients.




Section
      1.36  “ Phase
      III Trial ” .
      Phase
      III Trial means a pivotal clinical study of a Licensed Product in patients
      designed to confirm with statistical significance the efficacy and safety of
      a
      Licensed Product performed to provide a sufficient basis for an application
      for
      Regulatory Approval of such Licensed Product.




Section
      1.37  “ Regulatory
      Approval ” .
      Regulatory Approval means the approvals (including any applicable governmental
      price and reimbursement approvals), licenses, registrations or authorizations
      of
      Regulatory Authorities necessary for the commercial manufacture and sale of
      a
      product in a country or territory.




Section
      1.38  “ Regulatory
      Authority ” .
      Regulatory Authority means a federal, national, multinational, state, provincial
      or local regulatory agency, department, bureau or other governmental entity
      with
      authority over the testing, manufacture, use, storage, import, promotion,
      marketing or sale of a product in a country or territory.




Section
      1.39  “ Regulatory
      Filings ” .
      Regulatory Filings means any filing or application with any Regulatory Authority
      with respect to a Licensed Compound or Licensed Product, including
      without limitation any INDs or its foreign equivalent, Regulatory Approvals,
      and
      correspondence with the relevant Regulatory Authorities, as well as minutes
      of
      any material meetings, telephone conferences or discussions with the relevant
      Regulatory Authorities.




-7-




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




Section
      1.40  “ Royalty
      Term ” .
      Royalty
      Term means, with respect to each Licensed Product in each country of the
      Territory, the period commencing upon first commercial sale of such Licensed
      Product in such country and ending upon the later of (a) the expiration of
      the
      last-to-expire Valid Claim under the Licensed Patent Rights Covering such
      Licensed Product in such country, or (b) ***** years following first commercial
      sale of such Licensed Product in such country. For avoidance of doubt, the
      Royalty Term shall be determined on a country-by-country and Licensed
      Product-by-Licensed Product basis.




Section
      1.41  “ Senior
      Executives ” .
      Senior
      Executives means, with respect to PRESIDIO, the Chief Executive Officer (or
      a
      senior executive designated by such officer) and, with respect to XTL, the
      Chief
      Executive Officer (or a senior executive designated by such
      officer).




Section
      1.42  “ Series
      1 Compounds ” .
      Series
      1 Compounds means (a) the compounds claimed or disclosed in the Series 1 Patent
      Rights, (b) the compounds identified as “Series 1 Compounds” on Exhibit
      C ,
      and (c)
      Derivative Compounds of any compound set forth in either of the foregoing
      clauses (a) and (b); in the case of each of clauses (a), (b) and (c) above,
      regardless of whether or not any such compound has been synthesized by XTL
      and/or its Affiliates.




Section
      1.43  “ Series
      1 Licensed Products ” .
      Series
      1 Licensed Products means Licensed Products that contain any Series 1
      Compound(s).




Section
      1.44  “ Series
      1 Patent Rights ” .
      Series
      1 Patent Rights means (a) the Patent Rights set forth on Exhibit
      D ,
      (b)
      counterparts of the Patent Rights set forth on Exhibit
      D in any
      country of the Territory, and (c) all Patent Rights claiming priority from
      the
      Patent Rights described in either of the foregoing clauses (a) and (b) in any
      country of the Territory.




Section
      1.45  “ Series
      2-4 Compounds ” .
      Series
      2-4 Compounds means (a) any and all compounds claimed or disclosed in any Series
      2-4 Patent Right, (b) the compounds identified as “Series 2, 3 or 4 Compounds”
on Exhibit
      C ,
      and (c)
      Derivative Compounds of any compound set forth in either of the foregoing
      clauses (a) and (b); in the case of each of clauses (a), (b) and (c) above,
      regardless of whether or not any such compound has been synthesized by XTL
      and/or its Affiliates.




Section
      1.46  “ Series
      2-4 Licensed Products ” .
      Series
      2-4 Licensed Products means Licensed Products that contain any Series 2-4
      Compound(s).




Section
      1.47  “ Series
      2-4 Patent Rights ” .
      Series
      2-4 Patent Rights means (a) the Patent Rights set forth on Exhibit
      E ,
      (b)
      counterparts of the Patent Rights set forth on Exhibit
      E in any
      country of the Territory, and (c) all Patent Rights claiming priority from
      the
      Patent Rights described in either of the foregoing clauses (a) and (b) in any
      country of the Territory.




Section
      1.48  “ Series
      5-50 Compounds ” .
      Series
      5-50 Compounds means any and all compounds claimed or disclosed in any Patent
      Rights licensed or acquired by XTL from VivoQuest under the VivoQuest Asset
      Purchase Agreement or VivoQuest License Agreement, excluding the Series 1
      Compounds and the Series 2-4 Compounds.




-8-




Section
      1.49  “ Sublicense
      Income ” .
      Sublicense Income means, subject to Section 5.4, all amounts received by
      PRESIDIO and/or its Affiliates from Third Parties in connection with the
      sublicensing or licensing to such Third Parties of rights under Licensed Patent
      Rights and/or Licensed Technology to Develop and/or Commercialize any Series
      1
      Licensed Products, including without limitation all license fees, milestone
      payments and royalties, but excluding any of the following amounts received
      by
      PRESIDIO and/or its Affiliates from such Third Parties:




(a)  Amounts
      received as the purchase price for PRESIDIO’s and/or its Affiliates’ debt or
      equity securities, except to the extent such amounts exceed the fair market
      value of such debt or equity securities;




(b)  Amounts
      received for bona fide research and development activities undertaken for,
      or in
      collaboration with, such Third Parties, except to the extent such amounts exceed
      reasonable and customary funding amounts for such activities (e.g., cost
      reimbursement or reasonable FTE-based funding);




(c)  Amounts
      received for bona fide co-promotion and other commercial activities undertaken
      for, or in collaboration with, such Third Parties, except to the extent such
      amounts exceed reasonable and customary funding amounts for such activities
      (e.g., fees calculated and paid as cost reimbursement, reasonable per-detail
      fees or reasonable FTE-based funding);




(d)  In
      the
      event such license or sublicense is structured as a profit-sharing arrangement,
      PRESIDIO’s and its Affiliates’ share of revenue amounts that are offset by
      PRESIDIO’s and its Affiliates’ share of costs in the profit-share calculation
      (i.e., only PRESIDIO’s and its Affiliates’ share of net profits, as opposed to
      gross revenues, shall constitute Sublicense Income hereunder); and




(e)  Amounts
      received to cover Pass-Through Costs payable by PRESIDIO and/or its Affiliates
      under this Agreement, including without limitation any Pass-Through Costs owed
      by XTL to VivoQuest which are payable by PRESIDIO under Section 5.8 and any
      Pass-Through Costs payable by PRESIDIO pursuant to any Assigned Contracts and
      Additional Third Party Licenses.




Section
      1.50  “ Successful
      Completion ” .
      Successful Completion means (a) with respect to a Phase I Trial for a Licensed
      Product, the completion of such Phase I Trial with data that PRESIDIO determines
      is satisfactory to progress such Licensed Product to a Phase II Trial, and
      (b)
      with respect to a Phase III Trial for a Licensed Product, the completion of
      such
      Phase III Trial with data that (i) achieves the primary endpoint of such Phase
      III Trial or (ii) that PRESIDIO reasonably determines is suitable for inclusion
      as a pivotal trial in an NDA for such Licensed Product to a Regulatory
      Authority.




Section
      1.51  “ Territory ” .
      Territory means all countries of the world.




-9-


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




Section
      1.52  “Third
      Party” .
      Third
      Party means any person or entity other than a Party or any of its
      Affiliates.




Section
      1.53  “ Valid
      Claim ” .
      Valid
      Claim means, on a country-by-country basis, a claim of (a) an issued patent
      that
      (i) has not expired; (ii) has not been disclaimed; (iii) has not been cancelled
      or superseded, or if cancelled or superseded, has not been reinstated; and
      (iv)
      has not been revoked, held invalid, or otherwise declared unenforceable or
      not
      allowable by a tribunal or patent authority of competent jurisdiction over
      such
      claim in such country from which no further appeal has or may be taken; or
      (b) a
      patent application that has been pending less than ***** years from the earliest
      date from which such patent application claims priority and which claim has
      not
      been cancelled, withdrawn or abandoned or finally rejected by an administrative
      agency action from which no appeal can be taken.




Section
      1.54  “ VivoQuest
      Asset Purchase Agreement ” .
      VivoQuest Asset Purchase Agreement means the asset purchase agreement, dated
      as
      of August 11, 2005, between XTL Biopharmaceuticals Inc. and VivoQuest Inc.
      (including any successor-in-interest, “ VivoQuest ”).




Section
      1.55  *****




Section
      1.56  “ VivoQuest
      License Agreement ” .
      VivoQuest License Agreement means the license agreement, dated as of August
      11,
      2005, between XTL and VivoQuest.




Section
      1.57  “ VivoQuest
      Licensed Patents ” .
      VivoQuest Licensed Patents means the “Licensed Patents” as defined in the
      VivoQuest License Agreement.




Section
      1.58  Additional
      Definitions .
      Each of
      the following definitions is set forth in the section of this Agreement
      indicated below:




Definitions
            
            SectionAgreement
            
            PreambleApath
                License Agreement
            
            Exhibit
                ABreaching
                Party
            
            9.2Combination
                Product
            
            1.28CPR
            
            10.2Effective
                Date
            
            PreambleICDR
            
            10.3(a)Indemnified
                Party
            
            11.1(c)Indemnifying
                Party
            
            11.1(c)Invalidity
                Claim
            
            6.4Knowledge
            
            8.5PRESIDIO
            
            PreambleRetained
                Liabilities
            
            11.1(b)Severed
                Clause
            
            11.11Technology
                Transfer Period
            
            3.1TTC
            
            3.2Validity
                Challenge
            
            9.4(b)VivoQuest
            
            1.54XTL
            
            Preamble




-10-




**Article
      II**


Grant
      of License; Assigned Contracts; Exclusivity




Section
      2.1  License
      Grant .
      Subject
      to the terms and conditions of this Agreement, XTL hereby grants to PRESIDIO
      an
      exclusive (even as to XTL), royalty-bearing right and license under the Licensed
      Patent Rights and Licensed Technology, with the right to grant sublicenses,
      to
      Develop and Commercialize Licensed Compounds and Licensed Products in the Field
      in the Territory. Each sublicense granted hereunder shall be pursuant to a
      written agreement that is consistent with the terms and conditions of this
      Agreement, provided  that further
      sublicenses granted by any Third Party sublicensee to any of its affiliates
      shall not be required to be pursuant to written agreements (the term
“affiliates” as used in this sentence shall mean, with respect to a Third Party
      sublicensee, any Person that controls, is controlled by, or is under common
      control with such Third Party sublicensee, with “control” having the meaning
      provided in Section 1.2). PRESIDIO shall provide a copy of each such sublicense
      agreement entered into by PRESIDIO promptly following its execution; provided  that ,
      PRESIDIO shall be entitled to redact from the copy of such sublicense agreement
      provided to XTL terms that are not related to the determination of payments
      due
      to XTL under this Agreement or the consistency of such sublicense agreement
      with
      the terms and conditions of this Agreement; provided  further  that ,
      such
      copies of sublicense agreements provided by PRESIDIO to XTL shall constitute
      Confidential Information of PRESIDIO hereunder.




Section
      2.2  Assigned
      Contracts .
      As of
      the Effective Date, XTL shall, and shall cause its Affiliates to, assign to
      PRESIDIO, and PRESIDIO shall assume, all of XTL’s or the applicable Affiliate’s
      rights and obligations under the Assigned Contracts, provided , that XTL
      shall remain responsible for the Retained Liabilities. XTL shall, and shall
      cause its Affiliates to, take all reasonable further actions and execute all
      assignments or other documents requested by PRESIDIO as may be necessary or
      desirable to accomplish the foregoing assignments to PRESIDIO and to vest in
      PRESIDIO the rights set forth in this Section 2.2.




Section
      2.3  Exclusivity




(a)  During
      the term of this Agreement, neither XTL nor any of its Affiliates shall, or
      shall license, permit or assist any Third Party to, use any of the Series 1
      Compounds, the Series 2-4 Compounds, the Series 5-50 Compounds, any Derivative
      Compounds of the foregoing, or any other materials or Know- How licensed
      or acquired by XTL from VivoQuest, for any Development or Commercialization
      purpose relating or directed to the HCV Field in the Territory.




(b)  During
      the term of this Agreement, neither XTL nor any of its Affiliates shall, or
      shall license, permit or assist any Third Party to, Develop or Commercialize
      any
      Competing Product in the Territory; provided , however , that in the
      event that, after the Effective Date, a Third Party acquires XTL, then such
      Third Party shall not be bound by the restrictions provided in this Section
      2.3(b), and no Patents or Know-How owned or Controlled by such Third Party
      shall
      be or become subject to the licenses granted herein, provided , that such
      Third Party acquirer
      does not access or use any Licensed Compounds or Licensed Technology, or
      practice any invention Covered by any Licensed Patent Rights, in connection
      with
      such activities.




-11-




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




Section
      2.4  Retained
      Rights; Other Limitations .
      Without
      limiting Section 8.5(a), the rights granted to PRESIDIO herein, including
      without limitation the license granted to PRESIDIO in Section 2.1, as pertaining
      to Licensed Patent Rights and Licensed Technology that are Controlled, but
      are
      not owned, by XTL, shall be limited by any rights retained by Third Parties,
      or
      other limitations or conditions on XTL’s sublicensee’s rights to such Licensed
      Patent Rights and Licensed Technology. As of the Effective Date, such retained
      rights and limitations consist solely of the rights retained by the U.S.
      government pursuant to Section 2 of the VivoQuest License Agreement.




Section
      2.5  Section
      365(n) of the Bankruptcy Code .
      All
      rights and licenses granted to PRESIDIO under or pursuant to this Agreement
      are,
      and shall otherwise be, deemed to be, for purposes of Section 365(n) of the
      Bankruptcy Code, licenses of rights to “intellectual property” as defined under
      Section 101(35A) of the Bankruptcy Code. The Parties shall retain and may fully
      exercise all of their respective rights and elections under the Bankruptcy
      Code.




**Article
      III**


Technology
      Transfer




Section
      3.1  Technology
      Transfer .
      Without
      limiting the license granted to PRESIDIO pursuant to Section 2.1, XTL shall
      deliver, and shall cause XTL’s Affiliates to deliver, to PRESIDIO, commencing
      promptly following the Effective Date and for no additional consideration,
      (a)
      all Licensed Compounds and all other chemical or biological materials owned
      or
      Controlled by XTL or any of its Affiliates, that are necessary or useful for
      producing the Licensed Compounds or otherwise practicing the Licensed Patent
      Rights or Licensed Technology, (b) all patent files associated with the Licensed
      Patent Rights, including without limitation the complete texts of all patents
      and patent applications and copies of all office actions, office action
      responses and other official communications received from, or filed with, all
      relevant patent offices, in each case, in the possession or Control of XTL
      or
      any of its Affiliates, and (c) all Licensed Technology, including without
      limitation all laboratory notebooks, preclinical or clinical data, databases,
      designs, assays, protocols, analytical systems, discovery tools, reports and
      manufacturing documentation relating to the Development and/or Commercialization
      of any Licensed Compounds or Licensed Products, in each case, in the possession
      or Control of XTL or any of its Affiliates. XTL shall complete, and shall cause
      XTL’s Affiliates to complete, the delivery to PRESIDIO of all of the items
      listed in each of the foregoing clauses (a), (b) and (c) within a period of
      three (3) months following the Effective Date (the “ Technology
      Transfer Period ”).
      XTL
      shall make ***** and ***** reasonably available to PRESIDIO *****, and *****
      reasonably available to PRESIDIO until *****, in each case to answer any
      questions or provide instruction concerning the Licensed Compounds, Licensed
      Patent Rights, Licensed Technology and/or any of the other items delivered
      to
      PRESIDIO pursuant to this Section 3.1. During the Technology Transfer Period,
      XTL and its Affiliates shall take all such further reasonable actions as may
      be
      necessary or desirable to accomplish the foregoing transfers to PRESIDIO and
      to
      put PRESIDIO in actual possession of the foregoing information and
      materials.




-12-


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




Section
      3.2  Technology
      Transfer Committee; Decision-Making Authority .




(a)  Within
      ***** days following the Effective Date, the Parties shall establish a
      technology transfer committee (the “ TTC ”)
      to
      facilitate and oversee the technology transfer activities set forth in Section
      3.1 during the Technology Transfer Period. The TTC shall consist of no more
      than
      two (2) representatives from each Party, each of whom shall be appointed by
      the
      Senior Executive of the applicable Party. Each Party shall designate one such
      representative to serve as the co-chair of the TTC. Unless otherwise agreed
      by
      the Parties, the TTC shall remain in effect solely during the Technology
      Transfer Period.




(b)  The
      TTC
      shall have decision-making authority with respect to any technical matter
      relating to the technology transfer activities under Section 3.1, but shall
      have
      no authority to amend the scope of the licenses granted to PRESIDIO hereunder
      or
      amend any other contractual rights or obligations of either Party under this
      Agreement. All decisions of the TTC shall be made by consensus of the TTC
      co-chairs. If the TTC co-chairs are unable to reach consensus with respect
      to a
      particular matter within its purview, the matter shall be referred to the Senior
      Executives for resolution. If the Senior Executives are unable to resolve such
      matter within ***** days following such referral, the matter shall be resolved
      pursuant to Article X.




**Article
      IV**


Reports
      and Meetings; Diligence; Certain Regulatory and Manufacturing
      Activities




Section
      4.1  Development
      Reports; Meetings .




(a)  Within
      ***** prior to the first commercial launch of the first Licensed Product by
      PRESIDIO and/or any of its Affiliates or Third Party sublicensees, PRESIDIO
      shall provide to XTL a written report summarizing the activities undertaken
      by
      PRESIDIO, its Affiliates and Third Party sublicensees during the immediately
      preceding ***** period (or such shorter period as may be applicable with respect
      to the first and last such report) in connection with the Development and
      Commercialization of Licensed Products.




(b)  Prior
      to
      the first commercial launch of the first Licensed Product hereunder, PRESIDIO
      shall, upon reasonable request by XTL, at no cost to PRESIDIO, meet with XTL,
      no
      more frequently than on a semi-annual basis and at PRESIDIO’s corporate
      headquarters (or by telephone), to discuss generally the reports provided to
      XTL
      under the foregoing Section 4.1(a).




(c)  After
      the
      first commercial launch of the first Licensed Product by PRESIDIO and/or any
      of
      its Affiliates or Third Party sublicensees, PRESIDIO’s reporting obligations
      shall be limited to those set forth in Section 5.9(a) below.




(d)  Notwithstanding
      any of the foregoing, in the event that XTL is acquired by, or otherwise becomes
      an Affiliate of, a Person that is engaged in Development and/or
      Commercialization activities relating or directed to the HCV Field, PRESIDIO’s
      obligations under Section 4.1(a), Section 4.1(b) and Section 6.1(c) shall
      terminate.




-13-


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




Section
      4.2  Commercially
      Reasonable Efforts .
      PRESIDIO shall use Commercially Reasonable Efforts to Develop and Commercialize
      at least one Licensed Product for the prevention,
      treatment, palliation and/or control of any HCV indication in the United States,
      the EU and Japan. For purposes of clarity, PRESIDIO shall be deemed to have
      used
      Commercially Reasonable Efforts hereunder with respect to its Development and
      Commercialization activities in the EU if PRESIDIO Develops and Commercializes
      at least one Licensed Product for the prevention, treatment, palliation and/or
      control of any HCV indication in any ***** of the Major EU Countries.
      Notwithstanding anything to the contrary in this Agreement, however, XTL’s sole
      and exclusive remedy, and PRESIDIO’s sole and exclusive liability, for any
      breach by PRESIDIO of such obligation to exercise Commercially Reasonable
      Efforts shall be for XTL to exercise any right that XTL may have to terminate
      this Agreement as provided in Section 9.2.




Section
      4.3  Certain
      Regulatory and Manufacturing Activities .
      As
      between the Parties, PRESIDIO shall be responsible, at its expense, for all
      Development and Commercialization activities conducted by PRESIDIO and/or its
      Affiliates or Third Party sublicensees, including without
      limitation:




(a)  Filing
      applications for, and obtaining and maintaining, any necessary Regulatory
      Approvals with respect to the Development and/or Commercialization of Licensed
      Compounds or Licensed Products. As between the Parties, PRESIDIO shall own
      all
      Regulatory Filings with respect to Licensed Compounds and/or Licensed Products
      filed by or on behalf of PRESIDIO and/or its Affiliates or Third Party
      sublicensees; and




(b)  Manufacturing,
      or having manufactured by a Third Party manufacturer, all preclinical, clinical
      and commercial supply of Licensed Products, including without limitation
      Licensed Compounds and/or other components necessary for such Licensed
      Products.




**Article
      V**


Financial
      Provisions




Section
      5.1  License
      Payment .
      Within
      fourteen (14) days after the Effective Date, PRESIDIO shall make a one-time,
      non-refundable license payment to XTL of Three Million Nine Hundred Forty
      Thousand Dollars ($3,940,000).




Section
      5.2  Milestone
      Payments for Series 1 Licensed Products .
      Subject
      to Sections 5.4, 5.5(a), 5.6, 5.7 and 5.8(b), within ***** days after
      achievement of each of the following milestone events with respect to Series
      1
      Licensed Products by PRESIDIO or any of its Affiliates, PRESIDIO shall make
      the
      indicated one-time milestone payment to XTL; provided, however, that where
      a
      portion of a milestone payment is payable by XTL to VivoQuest as indicated
      in
      the parenthetical clauses included in the table below, such amount (that is,
      such portion of the total milestone payment) shall be payable by PRESIDIO to
      XTL
      within ***** days after the achievement of the relevant milestone event, except
      that the amount so payable upon the achievement of the milestone event indicated
      in row (h) in the table below shall be payable by PRESIDIO to XTL within *****
      days after the achievement of the relevant milestone event. *****:




-14-


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




Milestone
                Event
            
            Column
                A
              *****
            
            Column
                B
              **********
            
            
            *****
            
            
            **********
            
            
            *****
            
            
            **********
            
            
            *****
            
            
            **********
            
            
            *****
            
            
            **********
            
            
            *****
            
            
            **********
            
            
            *****
            
            
            **********
            
            
            *****
            
            
            **********
            
            
            *****
            
            
            **********
            
            
            *****
            
            
            *****




Each
      of
      the milestone payments payable
      pursuant to this Section 5.2 upon achievement of the corresponding milestone
      event shall be payable (x) only once, under either Column A or Column B above
      (but not both), irrespective of how many Licensed Products are Developed or
      Commercialized hereunder, (y) only upon achievement of the corresponding
      milestone event by PRESIDIO and/or its Affiliates, and not by any Third Party
      sublicensee of PRESIDIO or any of its Affiliates, except as and to the extent
      required by Section 5.8(a) and (z) with respect to the milestone payments set
      forth in clauses (a), (b), (c), (d), (e), (f) and (g) of the table above,
      subject to the limitations set forth in Section 5.4. In addition to the
      foregoing, the milestone payments above shall be reduced if PRESIDIO enters
      into
      an agreement with one or more Third Parties pursuant to which PRESIDIO grants
      such Third Party(ies) a sublicense or license under the Licensed Patent Rights
      and/or Licensed Technology to Develop and Commercialize any Series 1 Licensed
      Product in any of the countries indicated immediately below. Such reduction
      shall be given effect prior to any reduction of the above milestones payments
      as
      provided in Section 5.5 and Section 5.6 of this Agreement. Such reduction shall
      be in an amount equal to the percentage of the applicable milestone payment
      indicated below in connection with the grant of the foregoing rights in the
      specified country: *****. *****. Such reductions shall only be applied to
      milestone payments that are payable in connection with milestone events that
      are
      achieved after the execution and delivery of the relevant agreement(s) between
      PRESIDIO and such Third Party(ies) and shall not be given retroactive
      effect.




-15-


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




Section
      5.3  Royalties .
      During
      the Royalty Term applicable to sales of each Licensed Product in each country
      of
      the Territory, PRESIDIO shall pay to XTL the royalties set forth in Section
      5.3(a) or 5.3(b) below, as applicable, with the amount of such royalties
      calculated as a percentage of worldwide Net Sales of such Licensed Product
      during each Fiscal Year of PRESIDIO.




(a)  Royalties
      for Series 1 Licensed Products .
      Subject
      to Sections 5.5(b), 5.6, 5.7 and 5.8(b), PRESIDIO shall pay XTL the following
      royalty with respect to Net Sales, generated during the applicable Royalty
      Term,
      of each Series 1 Licensed Product (on a product-by-product basis) by PRESIDIO
      and/or its Affiliates (but not by any Third Party sublicensee of PRESIDIO or
      any
      of its Affiliates) during each Fiscal Year of PRESIDIO:




Annual
                Worldwide Net Sales of
              Series
                1 Licensed Product
            
            Percentage
                of
              Incremental
                Net Sales Amount*****
            
            **********
            
            **********
            
            **********
            
            *****





*****.




(b)  Royalties
      for Series 2-4 Licensed Products .
      PRESIDIO shall pay XTL a royalty of (i) *****of Net Sales by PRESIDIO and/or
      its
      Affiliates of a Series 2-4 Licensed Product during any period that such Series
      2-4 Licensed Product is Covered by a Valid Claim of any Licensed Patent Right,
      and (ii) ***** of Net Sales by any Third Party sublicensee of PRESIDIO and/or
      its Affiliates of a Series 2-4 Licensed Product during any period that such
      Series 2-4 Licensed Product is Covered by a Valid Claim of any Licensed Patent
      Right.




(c)  Royalties
      Payable Only Once .
      The
      obligation to pay royalties is imposed only once with respect to Net Sales
      of
      the same unit of a Licensed Product.




Section
      5.4  Sublicense
      Income for Series 1 Licensed Products .
      Subject
      to Section 5.8(a), PRESIDIO shall pay XTL the following percentage of Sublicense
      Income, with respect to the Development and/or Commercialization of any Series
      1
      Licensed Product by a Third Party sublicensee, which Sublicense Income is
      received by PRESIDIO and/or its Affiliates during Royalty Term applicable to
      such Series 1 Licensed Product in the country(ies) in which the activities
      giving rise to the Sublicense Income payment to PRESIDIO and/or its Affiliates
      occur:




(a)  *****;




(b)  *****;




-16-


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




(c)  *****;




(d)  *****.




Notwithstanding
      Section 5.2 and the foregoing provisions of this Section 5.4, and subject to
      the
      remaining provisions of this paragraph, PRESIDIO’s obligations to pay XTL (A)
      milestone payments upon the achievement by PRESIDIO or its Affiliates of the
      milestone events designated (a), (b), (c), (d), (e), (f) and (g) in the table
      in
      Section 5.2 and (B) payments pursuant to this Section 5.4 based on Sublicense
      Income comprised of upfront payments (that is, payments due in connection with
      the execution and delivery of a sublicense that are not contingent on the
      occurrence of other events or achievements) or milestone payments other than
      milestone payments based on the achievement by a Third Party sublicensee of
      sales milestones (i.e., the achievement of specified levels of sales of Series
      1
      Licensed Products *****. Notwithstanding the limitation on PRESIDIO’s payment
      obligations described in this Section, the amounts provided in Section 5.8
      shall
      remain due and payable in full in accordance with the terms set forth in Section
      5.8.





Section
      5.5  Reduction
      for Lack of Patent Coverage .




(a)  Each
      of
      the milestone payments payable by PRESIDIO pursuant to Section 5.2 above shall
      be reduced by ***** (i.e., reduced to ***** of the amount otherwise payable)
      in
      the event that the first Series 1 Licensed Product with respect to which the
      corresponding milestone event is achieved is not Covered by a Valid Claim of
      any
      Licensed Patent Rights at the time of such achievement; provided that if the
      same milestone event is subsequently achieved with one or more Series 1 Licensed
      Products that are Covered by a Valid Claim of a Licensed Patent Right at the
      time of such achievement, then the remainder of such milestone payment (i.e.,
      the ***** not previously paid) shall then become payable hereunder.




(b)  The
      royalty rate set forth in Section 5.3(a) above payable by PRESIDIO with respect
      to Net Sales by PRESIDIO and/or its Affiliates of any Series 1 Licensed Product
      for use in the Field in any country in the Territory shall be reduced to *****
      of Net Sales during any portion of the Royalty Term for such Series 1 Licensed
      Product in which such Series 1 Licensed Product in such country is not Covered
      by a Valid Claim of any Licensed Patent Rights.




Section
      5.6  Reduction
      for Pass-Through Costs Under Assigned Contracts and Additional Third Party
      Licenses .
      As
      between the Parties, PRESIDIO shall be responsible for paying all Pass-Through
      Costs required to be paid under the Assigned Contracts and any Additional Third
      Party Licenses; provided , however , that ,
      PRESIDIO shall have the right to reduce the milestone and royalty payments
      payable by PRESIDIO under Sections 5.2 and 5.3(a) above ***** of all such
      Pass-Through Costs payable by PRESIDIO hereunder, provided , that ,
      in no
      event shall any single milestone or royalty payment payable by PRESIDIO under
      Section 5.2 or 5.3(a) with respect to any Series 1 Licensed Product be reduced
      by more than ***** of the amount otherwise due to XTL under Section 5.2 or
      5.3(a). For the avoidance of doubt, no reduction shall be applied by PRESIDIO
      under this Section 5.6 with respect to the ***** required to be paid under
      the
      *****.




-17-


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




Section
      5.7  Priority
      of Reduction .
      In the
      event that the reductions provided for in Sections 5.5 and 5.6 would otherwise
      both be applicable to a milestone or royalty payment payable by PRESIDIO under
      Section 5.2 or 5.3(a), then only the reduction in Section 5.5 shall apply to
      such milestone or royalty payment.




Section
      5.8  Offset
      for Payment of VivoQuest Pass-Through Costs .
      As
      between the Parties, XTL shall be responsible for maintaining the VivoQuest
      License Agreement in full force and effect and for paying all amounts due to
      VivoQuest thereunder. Anything in this Agreement to the contrary
      notwithstanding, in addition to (but subject to PRESIDIO’s offset rights as
      provided below) any other amounts that may be payable hereunder:




(a)  If,
      at
      any time, Pass-Through Costs are owed by XTL to VivoQuest under the VivoQuest
      License Agreement as a result of the Development and/or Commercialization of
      Series 1 Licensed Products by a Third Party sublicensee of PRESIDIO or any
      of
      its Affiliates (but not by PRESIDIO or any of its Affiliates), then PRESIDIO
      shall pay XTL the amount of the Pass-Through Costs owed by XTL to VivoQuest; provided , however , that ,
      PRESIDIO shall have the right to offset such amount paid by PRESIDIO against
      any
      amounts otherwise payable, concurrently or subsequently, by PRESIDIO to XTL
      under Section 5.4.




(b)  If
      any
      amount payable by PRESIDIO to XTL under Section 5.2 or Section 5.3(a) is less
      than the corresponding Pass-Through Costs that are owed by XTL to VivoQuest
      under the VivoQuest License Agreement as a result of the Development and/or
      Commercialization of Series 1 Licensed Products by PRESIDIO and/or any of its
      Affiliates (but not by a Third Party sublicensee of PRESIDIO or any of its
      Affiliates), then PRESIDIO shall pay XTL the difference between (i) the amount
      paid by PRESIDIO under Section 5.2 or Section 5.3(a), and (ii) the amount of
      the
      Pass-Through Costs owed by XTL to VivoQuest.




(c)  PRESIDIO
      shall be obligated to pay XTL any Pass-Through Costs that are owed by XTL to
      VivoQuest under the VivoQuest License Agreement as a result of the Development
      and/or Commercialization of Series 2-4 Licensed Products by PRESIDIO and/or
      any
      of its Affiliates or Third Party sublicensees.




(d)  In
      the
      event that any Pass-Through Costs set forth in any of the foregoing clauses
      (a)
      through (c) are payable by PRESIDIO under such provisions, or any Pass-Through
      Costs referenced in the parenthetical clauses in Column A of the table in
      Section 5.2 are owed by XTL to VivoQuest, *****.




Section
      5.9  Reports
      and Accounting .




(a)  Reports;
      Payments .
      PRESIDIO shall deliver to XTL, within ***** days after the end of each calendar
      quarter, a good faith estimate of the royalties and Sublicense Income that
      will
      be paid to XTL for such calendar quarter (excluding any estimate of royalties
      which may be payable by PRESIDIO under Section 5.3(b)(ii) with respect to Net
      Sales of Series 2-4 Licensed Products by Third Party sublicensees of PRESIDIO
      and/or its Affiliates), and, within ***** days after the end of each calendar
      quarter, reasonably detailed written accountings of Net Sales and Sublicense
      Income of Licensed Products that are subject to payment obligations to XTL
      for
      such calendar quarter. Such quarterly reports shall indicate (i) gross sales,
      Net Sales, gross amounts received from Third Party sublicensees, and Sublicense
      Income on a Licensed Product-by-Licensed Product and country-by-country basis,
      and (ii) the calculation of payment amounts owed to XTL from such Net Sales
      and
      Sublicense Income. When PRESIDIO delivers such accounting to XTL, PRESIDIO
      shall
      also deliver all amounts due under Sections 5.3 and 5.4 to XTL for the
      calendar quarter.




-18-


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




(b)  Audits
      by XTL .
      PRESIDIO shall keep, and shall require its Affiliates **** and
      Third
      Party sublicensees to keep, records of the latest ***** years relating to gross
      sales, Net Sales, gross amounts received from Third Party sublicensees, and
      Sublicense Income, in each case as applicable, and all information relevant
      under Sections 5.2, 5.3, 5.4, 5.6, 5.7 and 5.8. For the sole purpose of
      verifying amounts payable to XTL, XTL shall have the right no more than once
      each calendar year, at XTL’s expense, to have XTL’s independent certified public
      accountants review such records in the location(s) where such records are
      maintained by PRESIDIO and/or its Affiliates or, with respect to records of
      Third Party sublicensees, either at PRESIDIO’s premises or the premises of such
      Third Party sublicensees, in each case as may be designated by PRESIDIO, upon
      ***** days’ prior notice and during regular business hours. Results of such
      review shall be made available to PRESIDIO. If the review reflects an
      underpayment to XTL, such underpayment shall be promptly remitted to XTL,
      together with interest calculated in the manner provided in Section 5.13. If
      the
      underpayment is equal to or greater than ***** of the aggregate amount that
      was
      otherwise due for any calendar year, PRESIDIO shall promptly reimburse XTL
      for
      the reasonable costs incurred in connection with such review. If the review
      reflects an overpayment to XTL, such overpayment shall be promptly refunded
      by
      XTL to PRESIDIO.




Section
      5.10  Currency
      and Method of Payments .
      All
      payments under this Agreement shall be made in United States dollars by transfer
      to such bank account as XTL may designate from time to time. Any royalties
      or
      portions of Sublicense Income due hereunder with respect to amounts in
      currencies other than United States dollars shall be payable in their United
      States dollar equivalents, calculated using the average applicable interbank
      transfer rate determined by reference to the currency trading rates published
      by The
      Wall Street Journal (Western
      U.S. edition) over all business days of the calendar quarter to which the report
      under Section 5.9(a) relates.




Section
      5.11  United
      States Dollars .
      All
      dollar ($) amounts specified in this Agreement are United States dollar
      amounts.




Section
      5.12  Tax
      Withholding .
      If
      withholding taxes are payable with respect to payments to XTL hereunder,
      PRESIDIO may withhold the required amount and pay it to the appropriate
      governmental authority. PRESIDIO
      will withhold only such amounts as are required to be withheld by law in the
      country from which payment is being made. PRESIDIO shall submit to XTL a copy
      of
      the remittance voucher and reasonably satisfactory evidence of payment of the
      corresponding taxes with the applicable royalty report, if possible, or within
      ***** days thereafter. PRESIDIO will make reasonable efforts and will reasonably
      cooperate with XTL and provide such information and records as XTL may
      reasonably require in connection with XTL obtaining any applicable reduction
      or
      exemption from withholding tax from tax authorities in any country.




-19-


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




Section
      5.13  Late
      Payments .
      PRESIDIO shall pay interest to XTL on the aggregate amount of any payment that
      is not paid on or before the date such payment is due under this Agreement
      at a
      rate per annum equal to *****.




Section
      5.14  Blocked
      Payments .
      In the
      event that, by reason of applicable laws or regulations in any country, it
      becomes impossible or illegal for PRESIDIO or its Affiliates to transfer, or
      have transferred on its behalf, royalties or other payments to XTL, such
      royalties or other payments shall be deposited in local currency in the relevant
      country to the credit of XTL in a recognized banking institution designated
      by
      XTL or, if none is designated by XTL within a period of ***** days, in a
      recognized banking institution selected by PRESIDIO or its
      Affiliates.




Section
      5.15  Costs
      and Expenses .
      Except
      as otherwise expressly set forth herein, each Party shall bear its own costs
      and
      expenses incurred in connection with the performance of its obligations
      hereunder.




**Article
      VI**


Intellectual
      Property Protection and Related Matters




Section
      6.1  Prosecution
      and Maintenance of Licensed Patent Rights .




(a)  Right
      to Prosecute and Maintain .
      As
      between the Parties, PRESIDIO shall have the first right to file and prosecute
      patent applications and maintain patents within the Licensed Patent Rights.
      Subject to Section 6.6 below, PRESIDIO shall use Commercially Reasonable Efforts
      to file and prosecute patent applications and maintain patents within the
      Licensed Patent Rights in the United States, Canada, the Major EU Countries
      and
      Japan in a manner that is intended to provide optimal protection for any
      Licensed Products that PRESIDIO may Develop and/or Commercialize in such
      countries, including without limitation seeking claims of reasonably broad
      scope, to the extent permitted under applicable law. Notwithstanding the
      foregoing, in the event that PRESIDIO decides to abandon or discontinue the
      filing, prosecution or maintenance of any non-provisional patent application
      or
      patent within the Licensed Patent Rights in any such country, then PRESIDIO
      shall notify XTL of such determination reasonably in advance of any loss of
      rights by XTL with respect to such patent application or patent. Thereafter,
      XTL
      shall have the right, upon written notice to PRESIDIO, to file, prosecute and
      maintain such non-provisional patent applications and patents, in its name
      and
      at its own expense, which patent applications and patents shall no longer be
      deemed “Licensed Patent Rights” under this Agreement. Notwithstanding anything
      in this Agreement to the contrary, XTL’s sole and exclusive remedy, and
      PRESIDIO’s sole and exclusive liability, for any decision by PRESIDIO not to
      file, prosecute and/or maintain any patent applications or patents hereunder
      shall be for XTL to assume such filing, prosecution and maintenance activities
      with respect to such patent applications or patents pursuant to this Section
      6.1.




(b)  Disclosure
      of New Inventions .
      XTL
      shall, and shall cause its Affiliates to, disclose to PRESIDIO any and all
      new
      inventions or other Know-How that (i) would constitute subject matter with
      respect to which a patent application within the Licensed Patent Rights may
      be
      filed hereunder or would otherwise constitute Licensed Technology hereunder,
      and
      (ii) becomes Controlled by XTL or any of its Affiliates during the term of
      this
      Agreement. XTL shall, and shall cause its Affiliates to, disclose such
      inventions or other such Know-How to PRESIDIO within ***** days after such
      Control exists, including without limitation reasonably detailed information
      with respect to such inventions or other such Know-How to enable PRESIDIO to
      obtain appropriate patent protection with respect to such inventions or other
      Know-How.




-20-






(c)  Cooperation .
      Subject
      to Section 4.1(d), each Party agrees to cooperate with the other Party with
      respect to the filing and prosecution of patent applications and maintenance
      of
      patents within the Licensed Patent Rights pursuant to this Section 6.1,
      including without limitation:




(i)  the
      execution of all such documents and instruments and the performance of such
      acts
      as may be reasonably necessary in order to permit the other Party to file and
      prosecute patent applications or maintain patents as provided for in Section
      6.1(a);




(ii)  making
      its employees, agents and consultants reasonably available to the other Party
      (or to the other Party’s authorized attorneys, agents or representatives), to
      the extent reasonably necessary to enable such other Party to file and prosecute
      patent applications or maintain patents as provided for in Section 6.1(a);
      and




(iii)  to
      provide the other Party with copies of all material official communications
      received from, or filed with, the relevant patent offices pertaining to the
      filing and prosecution of patent applications and maintenance of patents as
      provided for in Section 6.1(a).




Section
      6.2  Third
      Party Infringement .




(a)  Notifications
      of Third Party Infringement .
      Each
      Party agrees to notify the other Party when it becomes aware of any infringement
      of the Licensed Patent Rights or misappropriation of Licensed Technology, or
      the
      reasonable probability of such infringement or misappropriation, arising from
      or
      relating to the development, manufacture, offer for sale, sale, import or other
      use of any Third Party product.




(b)  Infringement
      Action .
      PRESIDIO shall decide whether to institute an infringement suit or take other
      appropriate action that it believes is reasonably required to protect the
      Licensed Patent Rights or Licensed Technology from such infringement or
      misappropriation. In the event that PRESIDIO brings an action pursuant to this
      Section 6.2(b), XTL shall cooperate with PRESIDIO to the extent reasonably
      requested by PRESIDIO, including without limitation joining the suit if
      requested by PRESIDIO and necessary or desirable.




(c)  Costs .
      PRESIDIO shall assume and pay all of its own and XTL’s out-of-pocket costs
      incurred in connection with any litigation or proceedings described in this
      Section 6.2; provided , however , that if XTL
      elects to be represented in such litigation or proceedings by separate counsel,
      XTL shall assume and pay for all of its own out-of-pocket costs incurred in
      connection with such litigation or proceedings.




(d)  Recoveries .
      Any
      recovery obtained by PRESIDIO as a result of any action or proceeding described
      in this Section 6.2, or from any counterclaim or similar claim asserted in
      a
      proceeding described in Section 6.3, by settlement or otherwise, shall be
      applied in the following order of priority:




-21-


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




(i)  first,
      to
      reimburse PRESIDIO for all litigation costs in connection with such proceeding
      paid by PRESIDIO and not otherwise recovered; and




(ii)  second,
      the remainder of the recovery shall be paid *****.




Section
      6.3  Claimed
      Infringement .
      In the
      event that a Party becomes aware of any claim that the Development or
      Commercialization of Licensed Products infringes Patent Rights or
      misappropriates the Know-How of any Third Party, such Party shall promptly
      notify the other Party.




Section
      6.4  Patent
      Invalidity Claim .
      If a
      Third Party at any time asserts a claim that any Licensed Patent Right is
      invalid, unenforceable and/or otherwise not infringed (an “ Invalidity
      Claim ”),
      whether as a defense in an infringement action brought by PRESIDIO pursuant
      to
      Section 6.2 or in an action brought against PRESIDIO or XTL referred to in
      Section 6.3, PRESIDIO shall have the right to prepare and formulate all
      responses to, and defend and settle, such Invalidity Claim. XTL shall cooperate
      with PRESIDIO with respect to such activities upon reasonable request by
      PRESIDIO.




Section
      6.5  Patent
      Marking .
      PRESIDIO agrees to comply with any applicable patent marking statutes in each
      country in which Licensed Products are sold by PRESIDIO and/or its
      Affiliates.




Section
      6.6  Certain
      Limitations .
      Without
      limiting the representations, warranties and covenants provided by XTL pursuant
      to Section 8.5, the Parties acknowledge that PRESIDIO may not be permitted
      to
      exercise all of the rights set forth in this Article VI with respect to Licensed
      Patent Rights that are not owned by XTL. Under such circumstances, XTL shall
      use
      reasonable efforts to obtain such rights for PRESIDIO and XTL shall provide
      prompt written notice to PRESIDIO of any such limitations on PRESIDIO’s rights
      under this Article VI. The existence of any such limitations, or XTL’s inability
      to avoid or eliminate any such limitations (provided XTL has used reasonable
      efforts to do so and subject to Section 8.5), shall not constitute a breach
      of
      this Agreement by XTL.




**Article
      VII**


Confidentiality




Section
      7.1  Confidential
      Information .
      All
      Confidential Information disclosed by a Party to the other Party during the
      term
      of this Agreement shall not be used by the receiving Party except in connection
      with the activities contemplated by this Agreement, shall be maintained in
      confidence by the receiving Party (except to the extent disclosure is reasonably
      necessary for Development and/or Commercialization of Licensed Products, for
      the
      filing, prosecution and maintenance of Patent Rights or to enforce the
      provisions of this Agreement), and shall not otherwise be disclosed by the
      receiving Party to any other person, firm, or agency, governmental or private
      (except as set forth Sections 7.2 or 7.3), without the prior written consent
      of
      the disclosing Party, except to the extent that the Confidential
      Information:




-22-




(a)  was
      known
      or used by the receiving Party prior to its date of disclosure to the receiving
      Party; or




(b)  either
      before or after the date of the disclosure to the receiving Party is lawfully
      disclosed to the receiving Party by sources other than the disclosing Party
      rightfully in possession of the Confidential Information; or




(c)  either
      before or after the date of the disclosure to the receiving Party becomes
      published or generally known to the public through no fault or omission on
      the
      part of the receiving Party; or




(d)  is
      independently developed by or for the receiving Party without reference to
      or
      reliance upon the Confidential Information; or




(e)  is
      required to be disclosed by the receiving Party to comply with applicable laws,
      regulations or rules, to defend or prosecute litigation or to comply with legal
      process, provided  that the
      receiving Party provides prior written notice of such disclosure to the
      disclosing Party and only discloses Confidential Information of the other Party
      to the extent necessary for such legal compliance or litigation
      purpose.




Section
      7.2  Employee,
      Director, Consultant and Advisor Obligations .
      PRESIDIO and XTL each agrees that it and its Affiliates shall provide
      Confidential Information received from the other Party only to the receiving
      Party’s respective (a) employees, directors, consultants and advisors, and to
      the employees, directors, consultants and advisors of the receiving Party’s
      Affiliates, who have a need to know such Confidential Information to assist
      the
      receiving Party in fulfilling its obligations under this Agreement, and (b)
      existing and prospective investors, acquirers, lenders, sublicensees,
      collaborators and Third Party contractors engaged in the Development and/or
      Commercialization of Licensed Compounds or Licensed Products, or in connection
      with such Party’s financing activities; provided  that PRESIDIO
      and XTL shall each remain responsible for any failure by any Person included
      in
      the foregoing clauses (a) and (b) to treat such Confidential Information as
      required under Section 7.1.




Section
      7.3  Publicity .




(a)  Upon
      execution of this Agreement, the Parties shall issue separate press releases,
      in
      form and substance mutually-agreed by the Parties, announcing the execution
      of
      this Agreement, a copy of each of which is attached hereto as Exhibit
      F .
      During
      the term of this Agreement, neither Party nor its Affiliates shall disclose
      this
      Agreement or make any public announcement, press release, filing or other
      disclosure concerning the existence, terms and conditions of this Agreement
      without the other Party’s prior written consent (which consent shall not be
      unreasonably withheld, conditioned or delayed), except (i) as set forth in
      Section 7.3(b) below, (ii) as required to comply with applicable laws,
      regulation or rules (including without limitation any rules of the United States
      Securities and Exchange Commission or similar regulatory agency, stock exchange
      or securities trading institution of such other jurisdictions whose laws may
      apply to a Party), or (iii) to existing and prospective investors, acquirers,
      lenders and other Third Parties in connection with such Party’s financing
      activities, provided , that each
      such Third Party is bound to treat such information as confidential. If a Party
      is required to make any such disclosure under applicable law, regulation or
      rule, such Party shall provide the other Party with a copy of the proposed
      text
      of any such written disclosure or the proposed content of any non-written
      disclosure, sufficiently in advance (to the extent practicable or permitted
      under applicable law, regulation or rule) of the scheduled release or disclosure
      thereof to afford the other Party a reasonable opportunity to review and comment
      upon such proposed disclosure and/or obtain confidential treatment with respect
      to such proposed disclosure.




-23-


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




(b)  Notwithstanding
      the foregoing, (i) PRESIDIO and/or any of its Affiliates and Third Party
      sublicensees shall have the right to disclose, in private communications, public
      announcements, press releases, filings or other disclosures, information
      concerning or related to its or their Development and Commercialization
      activities with respect to Licensed Products hereunder, and (ii) each Party
      and/or any of such Party’s Affiliates and/or, with respect to PRESIDIO, Third
      Party sublicensees, shall have the right to disclose information that is the
      same or substantially similar to information that has previously been disclosed
      under this Section 7.3; in the case of each of the foregoing clauses (i) and
      (ii), without having to grant the other Party the opportunity to review and
      comment on such proposed disclosure or obtain such other Party’s prior written
      consent.




Section
      7.4  Term .
      All
      obligations of confidentiality imposed under this Article VII shall expire
      *****
      following termination or expiration of this Agreement.




**Article
      VIII**


Representations
      and Warranties




Section
      8.1  Representations
      of Authority .
      PRESIDIO and XTL each represents and warrants to the other that, as of the
      Effective Date, it has full right, power and authority to enter into this
      Agreement and to perform its respective obligations under this
      Agreement.




Section
      8.2  Consents .
      PRESIDIO and XTL each represents and warrants that as of the Effective Date
      all
      necessary consents, approvals and authorizations of all government authorities
      and other Persons required to be obtained by such Party in connection with
      the
      execution, delivery and performance of this Agreement have been
      obtained.




Section
      8.3  No
      Conflict .
      PRESIDIO and XTL each represents and warrants that, as of the Effective Date,
      the execution and delivery of this Agreement and the performance of such Party’s
      obligations hereunder (a) do not conflict with or violate any requirement of
      applicable laws or regulations, and (b) do not conflict with, violate or breach
      or constitute a default of, or require any consent under, any contractual
      obligations of such Party, except such consents as have been obtained as of
      the
      Effective Date.




Section
      8.4  Employee,
      Director, Consultant and Advisor Obligations .
      PRESIDIO and XTL each represents and warrants that, as of the Effective Date,
      each of its and its Affiliates’ employees, directors, consultants and advisors
      has executed an agreement or has an existing obligation under law obligating
      such employee, director, consultant or advisor to maintain the confidentiality
      of Confidential Information to the extent required under Article
      VII.




Section
      8.5  Intellectual
      Property .
      XTL
      represents, warrants and covenants to PRESIDIO that:




-24-


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




(a)  VivoQuest
      has assigned to XTL all right, title and interest in and to the VivoQuest
      Licensed Patents, a complete and accurate list of which VivoQuest Licensed
      Patents are included on Exhibit
      D and Exhibit
      E .
      XTL is
      the sole and exclusive owner (subject to Section 2.4) of all right, title and
      interest in and to the VivoQuest Licensed Patents and the other Patent Rights
      set forth on Exhibit
      D and Exhibit
      E ,
      and, as
      of the Effective Date, is the sole and exclusive owner of all right, title
      and
      interest in and to, or has obtained exclusive rights to, the Licensed Compounds
      and Licensed Technology;




(b)  Each
      of
      XTL’s and its Affiliates’ current and former employees, directors, consultants
      and contractors has executed an agreement assigning to XTL or XTL’s Affiliate
      all of its or his or her right, title and interest in and to any inventions
      developed in the course of its or his or her employment or engagement with
      XTL
      or XTL’s Affiliate, and such agreements are valid and binding on all such
      current and former employees, directors, consultants and
      contractors;




(c)  To
      the
      Knowledge of XTL, each patent and patent application included within the
      Licensed Patent Rights sets forth a complete and accurate list of all
      inventors;




(d)  XTL
      has
      the right to grant to PRESIDIO the rights and licenses to Licensed Compounds,
      Licensed Patent Rights and Licensed Technology granted in this
      Agreement;




(e)  XTL
      and
      its Affiliates have not granted, and during the term of this Agreement XTL
      will
      not grant and will cause its Affiliates not to grant, any rights to any Third
      Party (including without limitation VivoQuest or any of the counterparties
      to
      any Assigned Contracts) which would conflict with the rights granted to PRESIDIO
      hereunder;




(f)  None
      of
      the Licensed Patent Rights procured by XTL or its Affiliates and, to the
      Knowledge of XTL, none of the Licensed Patent Rights procured by any Third
      Party
      was fraudulently procured from the relevant governmental patent granting
      authority;




(g)  To
      the
      Knowledge of XTL, the practice of the Licensed Patent Rights and Licensed
      Technology as contemplated under this Agreement does not violate the
      intellectual property rights of any Third Party, and, as of the Effective Date,
      no claim, demand or suit has been made, or proceeding initiated, nor is any
      such
      claim, demand, suit or proceeding pending or threatened, that asserts the
      invalidity, misuse or unenforceability of the Licensed Patent Rights or Licensed
      Technology; *****;




(h)  To
      the
      Knowledge of XTL, none of the Licensed Patent Rights are being infringed, nor
      is
      any Licensed Technology being misappropriated, by any Third Party;




(i)  All
      necessary registration, maintenance and renewal fees for Licensed Patent Rights
      have been paid on time, *****;




(j)  Exhibits
      D and E provide
      a complete and accurate listing of the Licensed Patent Rights as of the
      Effective Date, including without limitation the VivoQuest Licensed Patents,
      and
      XTL does not own or otherwise Control any Patent Rights other than the Patent
      Rights listed on Exhibits
      D and E that
      claim or disclose any Licensed Compounds or Licensed Technology;




-25-


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




(k)  Exhibit
      C provides
      a complete and accurate listing of all Series 1 Compounds and Series 2-4
      Compounds that are included in XTL’s and/or its Affiliates’ databases,
      laboratory notebooks and/or other records, or that have otherwise been
      identified, studied, screened or evaluated by XTL and/or its Affiliates,
      regardless of whether or not such compounds have been synthesized by XTL or
      any
      of its Affiliates;




(l)  *****;




(m)  Attached
      as Exhibits
      A and B are all
      complete and accurate copies of all Third Party agreements to which XTL or
      any
      XTL Affiliate is a party as of (or, solely with respect to the Assigned
      Contracts, immediately prior to) the Effective Date relating to the Licensed
      Compounds, Licensed Patent Rights and/or Licensed Technology. Except for the
      VivoQuest License Agreement, the VivoQuest Asset Purchase Agreement and Assigned
      Contracts, neither XTL nor any XTL Affiliate, as of (or, except for the Assigned
      Contracts, immediately prior to) the Effective Date, is a party to, or is
      otherwise bound by, any agreement pursuant to which any Third Party has any
      economic or other interest with respect to the Development and/or
      Commercialization of the Licensed Compounds or Licensed Products, or any
      ownership rights in any of the Licensed Compounds, Licensed Patent Rights and/or
      Licensed Technology;




(n)  The
      VivoQuest License Agreement, the VivoQuest Asset Purchase Agreement and all
      Assigned Contracts are in full force and effect, and XTL and/or its Affiliates
      are in full compliance with the terms of such agreements, *****, no dispute
      presently exists, nor has XTL received any notice of any such claim of breach
      or
      dispute nor, to the Knowledge of XTL, is any such claim pending or threatened,
      between XTL and the counterparty to any such agreement that would jeopardize
      any
      of the rights or licenses granted to PRESIDIO under this Agreement, and, to
      the
      Knowledge of XTL, there is no basis for any such claim of breach or
      dispute;




(o)  During
        the term of this Agreement, XTL shall, and shall cause its Affiliates to,
        comply
        with all terms and conditions of, and shall not, and shall cause its Affiliates
        not to, without the prior written consent of PRESIDIO, amend, terminate,
        or make
        or waive any claims or rights under, or grant any rights to VivoQuest or
        any
        other Third Party in connection with, the VivoQuest License Agreement or
        the
        VivoQuest Asset Purchase Agreement, in any manner that would adversely affect
        the rights granted to PRESIDIO under this Agreement, or take any action or
        fail
        to take any action that would give VivoQuest the right to amend or terminate
        the
        VivoQuest License Agreement or the VivoQuest Asset Purchase Agreement or
        would
        otherwise adversely affect the rights granted to PRESIDIO under this
        Agreement;
  (p)  XTL
        and
        its Affiliates have obtained all necessary consents to assign the Assigned
        Contracts to PRESIDIO hereunder;
  -26-


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




(q)  To
      the
      Knowledge of XTL, all written statements and other writings furnished by XTL
      or
      its Affiliates pursuant to or in connection with this Agreement or the
      transactions contemplated hereby are complete and accurate in all material
      respects. No representation or warranty by XTL in this Agreement contains any
      untrue statement of a material fact or omits to state any material fact
      necessary in order to make any statement contained herein not misleading. To
      the
      Knowledge of XTL, there is no fact, event or condition that would adversely
      affect PRESIDIO’s rights under this Agreement that has not been set forth in
      this Agreement or disclosed by XTL to PRESIDIO in writing; and




(r)  *****.




The
      term
“Knowledge” means the actual knowledge of ***** as of the Effective Date. For
      avoidance of doubt, anything to the contrary herein notwithstanding, XTL makes
      no representations or warranties with respect to any Derivative
      Compounds.




Section
      8.6  No
      Warranties . EXCEPT
      AS OTHERWISE EXPRESSLY SET FORTH HEREIN, THE PARTIES MAKE NO REPRESENTATIONS
      AND
      EXTEND NO WARRANTIES OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING WITHOUT
      LIMITATION ANY WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR
      PURPOSE. IN PARTICULAR, PRESIDIO EXPRESSLY DISCLAIMS ANY REPRESENTATION OR
      WARRANTY THAT ANY LICENSED COMPOUND OR LICENSED PRODUCT WILL BE SUCCESSFULLY
      DEVELOPED OR COMMERCIALIZED.




**Article
      IX**


Term
      and Termination




Section
      9.1  Term . This
      Agreement shall become effective as of the Effective Date, may be terminated
      as
      set forth in this Article IX, and otherwise remains in effect until the
      expiration of all of PRESIDIO’s payments obligations pursuant to Article V. Upon
      expiration of this Agreement, on a Licensed Product-by-Licensed Product and
      country-by-country basis, the license granted to PRESIDIO under Section 2.1
      shall convert to a non-exclusive, perpetual, fully paid-up, non-royalty-bearing
      license.




Section
      9.2  Termination
      For Material Breach . Upon
      any material breach of this Agreement by either Party (in such capacity, the
      “ Breaching
      Party ”),
      the
      other Party may terminate this Agreement by providing ***** days’ written notice
      to the Breaching Party, specifying the material breach. The termination shall
      become effective at the end of the ***** day period unless (a) the Breaching
      Party cures such material breach during such ***** day period or (b) if the
      material breach is not susceptible to cure within such ***** day period, the
      Breaching Party is diligently pursuing a cure and effects such cure within
      an
      additional ***** days after the end of such initial ***** day period.
      Notwithstanding any of the foregoing, (x) if the non-Breaching Party gives
      the
      Breaching Party notice pursuant to this Section 9.2 of a material breach by
      such
      Breaching Party, and the Breaching Party notifies the non-Breaching Party within
      the applicable cure period set forth in the immediately preceding sentence
      that
      such Breaching Party disputes such basis for termination pursuant to this
      Section 9.2, then this Agreement shall not terminate unless and until the
      arbitrator issues a final award pursuant to Article X upholding such basis
      for
      termination (or unless and until the Breaching Party is no longer disputing
      such
      basis, if earlier) and within ***** days thereafter the Breaching Party fails
      to
      comply with the terms of such final award issued by the arbitrator, and (y)
      if
      any uncured material breach by PRESIDIO of its diligence obligations under
      Section 4.2 is limited to only one or two of the following territories, then
      XTL
      may terminate this Agreement solely with respect to such territory or
      territories: (i) the EU, (ii) the United States, and (iii) Japan. Both Parties
      shall perform all of their respective obligations hereunder during the process
      of conducting any dispute resolution hereunder, including without limitation,
      the payment of all undisputed amounts as and when they become due and payable
      hereunder.




-27-


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





Section
      9.3  Termination
      for Convenience .
      PRESIDIO may terminate this Agreement at any time upon ***** days prior written
      notice to XTL for any or no reason.




Section
      9.4  Effect
      of Material Breach or Patent Validity Challenge by XTL or its
      Affiliates .




(a)  In
      the
      event that this Agreement is terminated by PRESIDIO pursuant to Section 9.2
      above as a result of XTL’s uncured material breach (other than a material breach
      by a Third Party acquirer of XTL, or by XTL or any of its Affiliates, following
      an acquisition transaction resulting in a change of control of XTL or of all
      or
      substantially all of its business or assets), then PRESIDIO shall have the
      option of (i) actually terminating this license, in which case the provisions
      of
      Section 9.5(c) shall apply and become effective, and pursuing any remedies
      that
      may be available to it hereunder or at law, or (ii) not exercising such
      termination right and continuing the licenses and this Agreement, in accordance
      with the terms and conditions set forth herein, provided that (A) the amounts
      that become due under Article V shall, as of the date of such waiver and for
      the
      remainder of the term of this Agreement, be reduced by ***** (after application
      of all other reductions and offsets that may be applicable); provided that
      the
      amounts provided in Section 5.8 shall remain due and payable in full in
      accordance with the terms set forth in Section 5.8 and (B) PRESIDIO shall cease
      to have any further obligation pursuant to Article IV as of the date of such
      waiver and for the remainder of the term of this Agreement.




(b)  If
      (i)
      XTL or any of its Affiliates intentionally initiates, or encourages or knowingly
      provides assistance to any Third Party with respect to, any action seeking
      a
      determination that any of the Licensed Patent Rights in any country are invalid,
      unenforceable and/or not infringed (including without limitation a request
      for
      reexamination of any Licensed Patent Rights or the institution of or
      participation in any opposition, interference or similar administrative
      proceeding adverse to the validity or enforceability of any Licensed Patent
      Rights) (“ Validity
      Challenge ”)
      or
      (ii) a Third Party acquirer of XTL, or XTL or any of its Affiliates, following
      an acquisition transaction resulting in a change of control of XTL or of all
      or
      substantially all of its business or assets, materially breaches this Agreement
      and fails to cure the breach such that PRESIDIO has the right to terminate
      this
      Agreement pursuant to Section 9.2 above, then (A) the license granted to
      PRESIDIO under Section 2.1 shall automatically convert to a perpetual, fully
      paid-up, non-royalty-bearing license; provided that the amounts provided in
      Section 5.8 shall remain due and payable in full in accordance with the terms
      set forth in Section 5.8 and (B) PRESIDIO shall cease to have any further
      obligation pursuant to Article IV or Article V (other than Section 5.8 and,
      to
      the extent applicable to payments owed to VivoQuest, Sections 5.9, 5.10 and
      5.11).




-28-


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





(c)  The
      reduction of payments in connection with PRESIDIO’s election not to exercise its
      termination right referenced above in Section 9.4(a)(ii) and in connection
      with
      the license conversion referenced above in Section 9.4(b) is used for the
      convenience of the Parties and is not intended to be a penalty to be paid by
      XTL. The Parties acknowledge that there will be difficulties in proving the
      amount and extent of PRESIDIO’s losses resulting from such uncured material
      breach or Validity Challenge. The Parties also agree that the compensation
      attributable to such reduction of payments is a reasonable pre-estimate of
      the
      probable losses which would be suffered by PRESIDIO.




Section
      9.5  Effects
      of Termination.




(a)  If
      this
      Agreement is terminated in its entirety by XTL as a result of PRESIDIO’s uncured
      material breach pursuant to Section 9.2 above, or on a territory-by-territory
      basis as a result of PRESIDIO’s uncured material breach of its diligence
      obligations with respect to a territory as described in Section 9.2(y) above,
      then the following provisions shall be applicable:




(i)  In
      each
      of the above instances of a termination of this Agreement, XTL shall have the
      right to terminate the license granted by XTL to PRESIDIO under Section 2.1,
      subject to Section 9.6 below and, in the case of an uncured material breach
      by
      PRESIDIO of its diligence obligations which breach is limited to only one or
      two
      of the territories identified in Section 9.2(y), the termination shall be
      limited to such territory(ies); and




(ii)  PRESIDIO
      shall return to XTL all Licensed Technology and other items delivered by XTL
      to
      PRESIDIO pursuant to Section 3.1, to the extent such Licensed Technology and
      other items remain in existence as of such termination; provided that PRESIDIO
      shall not be required to return the Licensed Technology or other items delivered
      by XTL to PRESIDIO pursuant to Section 3.1 if XTL terminates PRESIDIO’s rights
      hereunder only in regard to certain territories and not the entire Territory
      as
      provided in Section 9.2(y) above; and




(iii)  PRESIDIO
      shall not, directly or with or through its Affiliates, and subject to Section
      9.6 below, Third Party sublicensees or other Third Parties, continue the
      Commercialization of any Licensed Compounds or Licensed Products for a period
      of
      ***** following such termination, such restriction to apply to the entire
      Territory if ** XTL
      terminates the Agreement pursuant to Section 9.2, and, if such termination
      is
      only applicable to certain territories, then such restriction shall apply only
      to the territories to which such termination applies; provided  that if, at
      the time of such termination, PRESIDIO and/or any of its Affiliates and/or
      Third
      Party sublicensees is engaged in the Commercialization of Licensed Products
      and
      has commercial inventory (including work-in-process inventory) of Licensed
      Products, PRESIDIO and/or such Affiliate(s) and/or Third Party sublicensee(s)
      may complete the manufacture of any work-in-process inventory and continue
      to
      commercially distribute and sell all such existing inventory following
      termination, subject to PRESIDIO continuing to pay XTL all amounts due under
      this Agreement with respect to such continuing Commercialization.




-29-


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





(b)  If
      this
      Agreement is terminated by PRESIDIO pursuant to Section 9.3, then the following
      provisions shall be applicable:




(i)  The
      license granted by XTL to PRESIDIO under Section 2.1 shall terminate; and




(ii)  PRESIDIO
      shall return to XTL all Licensed Technology and other items delivered by XTL
      to
      PRESIDIO pursuant to Section 3.1, to the extent such Licensed Technology and
      other items remain in existence as of such termination; and




(iii)  PRESIDIO
      shall not, directly or with or through its Affiliates, Third Party sublicensees
      or other Third Parties, continue the Development and Commercialization of any
      Licensed Compounds or Licensed Products for a period of ***** following such
      termination.




(c)  If
      this
      Agreement is terminated by PRESIDIO as described in Section 9.4(a)(i), then
      the
      following provisions shall be applicable:




(i)  The
      license granted by XTL to PRESIDIO under Section 2.1 shall terminate; and




(ii)  PRESIDIO
      shall return to XTL all Licensed Technology and other items delivered by XTL
      to
      PRESIDIO pursuant to Section 3.1, to the extent such Licensed Technology and
      other items remain in existence as of such termination; and




(iii)  PRESIDIO
      shall not, directly or with or through its Affiliates, Third Party sublicensees
      or other Third Parties, continue the Commercialization of any Licensed Compounds
      or Licensed Products for a period of ***** following such
      termination.




(d)  The
      license termination and other rights set forth in this Section 9.5 shall,
      subject to Section 4.2, be in addition to any and all other remedies that XTL
      may have in connection with such a termination of this Agreement.




Section
      9.6  Survival . Upon
      expiration or termination of this Agreement for any reason, nothing in this
      Agreement shall be construed to release either Party from any obligations that
      accrue prior to the effective date of expiration or termination, and the
      following provisions shall expressly survive any such expiration or termination:
      Section 2.2, Section 2.5, Section 9.1, Section 9.4, Section 9.5, this Section
      9.6 and Article V (solely as pertaining to payment obligations (a) that are
      due
      and payable as of the effective date of termination or expiration, (b) that
      have
      accrued prior to the date of termination or expiration but for which the payment
      due date falls after the date of termination or expiration or (c) that become
      payable after termination pursuant to Section 9.5(a)(iii)), Article VII, Article
      X and Article XI. In addition, any sublicense granted by PRESIDIO and/or any
      of
      its Affiliates to a Third Party under the license granted by XTL to PRESIDIO
      in
      Section 2.1 shall survive expiration or termination of this Agreement, provided  that such
      termination did not arise out of the actions of such Third Party; provided  further  that the
      Third Party continues to comply in all material respects with the terms and
      conditions of such sublicense.




-30-


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





**Article
      X**


Dispute
      Resolution




Section
      10.1  Referral
      to Senior Executives . Except
      as set forth in Section 3.2(b), any dispute arising out of or relating to this
      Agreement shall first be referred to the Senior Executives of both Parties
      for
      resolution. Such Senior Executives shall attempt in good faith to resolve such
      dispute within ***** days following such referral. If the Senior Executives
      cannot resolve such dispute within such ***** day period, then either Party
      may
      make a written demand for formal dispute resolution pursuant to Section
      10.2.




Section
      10.2  Mediation . If the
      Senior Executives are unable to resolve any dispute referred to them as set
      forth in Section 10.1, such dispute shall then be referred to non-binding
      mediation upon either Party’s written demand for formal dispute resolution. Such
      mediation shall be conducted by an impartial mediator in accordance with The
      CPR
      Mediation Procedure for Business Disputes (Revised 1998) of the CPR Institute
      for Dispute Resolution (“ CPR ”).
      The
      Parties shall select, by mutual agreement, a mediator who has had both training
      and experience as a mediator of general corporate and commercial matters in
      the
      biotechnology and/or pharmaceutical industry. If the Parties cannot agree upon
      the selection of the mediator within ***** days after initiation thereof, the
      mediator shall be appointed by the President of the CPR in accordance with
      the
      criteria set forth in the preceding sentence. Within ***** days after the
      selection of the mediator, the Parties and their respective legal counsel will
      meet with the mediator for one mediation session of at least four hours. If
      any
      dispute cannot be settled during such mediation session or during any mutually
      agreed continuation of such session, either Party may give to the mediator
      and
      the other Party written notice declaring the mediation process at an end, and
      such dispute will be resolved by binding arbitration pursuant to Section 10.3
      below. The costs of any mediation pursuant to this Section 10.2 will be shared
      equally by the Parties.




Section
      10.3  Arbitration .




(a)  If
      any
      dispute is not resolved by the Senior Executives pursuant to Section 10.1 or
      through mediation pursuant to Section 10.2, either Party may submit such dispute
      to arbitration upon written notice to the other Party. Within ***** days after
      receipt of such notice, the Parties shall designate in writing a single
      arbitrator to resolve the dispute; provided , however , that if the
      Parties cannot agree on an arbitrator within such ***** day period, the
      arbitrator shall be selected by the International Centre for Dispute Resolution
      (the “ ICDR ”).
      The
      arbitrator shall be a lawyer with biotechnology and/or pharmaceutical industry
      legal experience, and shall not be an Affiliate, employee, consultant, officer,
      director or stockholder of any Party.




(b)  Within
      ***** days after the designation of the arbitrator, the arbitrator and the
      Parties shall meet, at which time the Parties shall be required to set forth
      in
      writing all disputed issues and a proposed ruling on the merits of each such
      issue.




(c)  The
      arbitrator shall set a date for a hearing, which shall be no later than *****
      days after the submission of written proposals pursuant to Section 10.3(b),
      to
      discuss each of the issues identified by the Parties. The Parties shall have
      the
      right to be represented by counsel. Except as provided herein, the arbitration
      shall be governed by the International Dispute Resolution Procedures of the
      ICDR; provided , however ,
      that
      the United States Federal Rules of Evidence shall apply with regard to the
      admissibility of evidence and the arbitration shall be conducted by a single
      arbitrator.




-31-


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





(d)  The
      arbitrator shall use his or her best efforts to rule on each disputed issue
      within ***** days after the completion of the hearings described in Section
      10.3(c). The determination of the arbitrator as to the resolution of any dispute
      shall be binding and conclusive upon all Parties. All rulings of the arbitrator
      shall be in writing and shall be delivered to the Parties.




(e)  The
      (i)
      attorneys’ fees of the Parties in any arbitration, (ii) fees of the arbitrator
      and (iii) costs and expenses of the arbitration shall be borne by the Parties
      as
      determined by the arbitrator.




(f)  Any
      arbitration pursuant to this Section 10.3 shall be conducted in New York, New
      York. Any arbitration award may be entered in and enforced by any court of
      competent jurisdiction.




Section
      10.4  No
      Limitation .
      Nothing in Section 10.1, Section 10.2 or Section 10.3 shall be construed as
      limiting in any way the right of a Party to seek an injunction or other
      equitable relief with respect to any actual or threatened breach of this
      Agreement or to bring an action in aid of arbitration. Should any Party seek
      an
      injunction or other equitable relief, or bring an action in aid of arbitration,
      then for purposes of determining whether to grant such injunction or other
      equitable relief, or whether to issue any order in aid of arbitration, the
      dispute underlying the request for such injunction or other equitable relief,
      or
      action in aid of arbitration, may be heard by the court in which such action
      or
      proceeding is brought.




**Article
      XI**


Miscellaneous
      Provisions




Section
      11.1  Indemnification .




(a)  PRESIDIO .
      PRESIDIO agrees to defend XTL, its Affiliates and their respective directors,
      officers, employees and agents at PRESIDIO’s cost and expense, and shall
      indemnify and hold harmless XTL and its Affiliates and their respective
      directors, officers, employees and agents from and against any liabilities,
      losses, costs, damages, fees or expenses (including without limitation
      reasonable attorneys’ fees) arising out of any Third Party claim relating to or
      arising out of (i) any breach by PRESIDIO of any of its representations,
      warranties or covenants pursuant to this Agreement, (ii) any failure by PRESIDIO
      to make payment of any Pass-Through Costs which are payable by PRESIDIO under
      this Agreement as a result of the Development and/or Commercialization of
      Licensed Products by PRESIDIO or its Affiliates or Third Party sublicensees,
      (iii) any liabilities and obligations of PRESIDIO under the Assigned Contracts
      that arise after the date of assignment of such Assigned Contracts to PRESIDIO
      hereunder, excluding the Retained Liabilities, (iv) any action by PRESIDIO
      in
      breach of this Agreement causing a breach of the VivoQuest License Agreement,
      (v) any action by PRESIDIO causing a breach of any Additional Third Party
      Agreements or any Assigned Contracts, or (vi) the Development and/or
      Commercialization of a Licensed Product by PRESIDIO or its Affiliates or Third
      Party sublicensees, in each case except to the extent that such claim relates
      to
      or arises out of any breach by XTL of any of its representations or warranties
      pursuant to this Agreement or any breach by XTL or its Affiliates of the
      VivoQuest License Agreement, the VivoQuest Asset Purchase Agreement or any
      Assigned Contract.




-32-


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





(b)  XTL .
      XTL
      agrees to defend PRESIDIO, its Affiliates and their respective directors,
      officers, employees and agents at XTL’s cost and expense, and shall indemnify
      and hold harmless PRESIDIO and its Affiliates and their respective directors,
      officers, employees and agents from and against any liabilities, losses, costs,
      damages, fees or expenses (including without limitation reasonable attorneys’
fees) arising out of (i) any Third Party claim relating to or arising out
      of (A) any breach by XTL of any of its representations, warranties or covenants
      pursuant to this Agreement, (B) any liabilities and obligations of XTL and/or
      its Affiliates under the Assigned Contracts that have accrued prior to the
      date
      of assignment of such Assigned Contracts to PRESIDIO hereunder (the
“ Retained
      Liabilities ”),
      or
      (C) without limiting the foregoing clauses (A) or (B), or any of XTL’s
      representations, warranties or covenants in Section 8.5, any breach by XTL
      or
      its Affiliates of the VivoQuest License Agreement, the VivoQuest Asset Purchase
      Agreement or any Assigned Contract; (ii) any claim by any existing or former
      employee, director, shareholder or consultant of XTL or any of its Affiliates,
      or of VivoQuest, to any right, title or interest in any of the Licensed Patent
      Rights, Licensed Compounds or Licensed Technology which, if such claim were
      successful, would limit or impair any of the rights granted hereunder to
      PRESIDIO; *****.




(c)  Claims
      for Indemnification .
      A
      Person entitled to indemnification under this Section 11.1 (an “ Indemnified
      Party ”)
      shall
      give prompt written notification to the Person from whom indemnification is
      sought (the “ Indemnifying
      Party ”)
      of the
      commencement of any action, suit or proceeding relating to a Third Party claim
      for which indemnification may be sought or, if earlier, upon the assertion
      of
      any such claim by a Third Party (it being understood and agreed, however, that
      the failure by an Indemnified Party to give notice of a third-party claim as
      provided in this Section 11.1(c) shall not relieve the Indemnifying Party of
      its
      indemnification obligation under this Agreement except and only to the extent
      that such Indemnifying Party is actually damaged as a result of such failure
      to
      give notice). Within ***** days after delivery of such notification, the
      Indemnifying Party may, upon written notice thereof to the Indemnified Party,
      assume control of the defense of such action, suit, proceeding or claim with
      counsel reasonably satisfactory to the Indemnified Party. If the Indemnifying
      Party does not assume control of such defense, the Indemnified Party shall
      control such defense. The Party not controlling such defense may participate
      therein at its own expense; provided  that ,
      if the
      Indemnifying Party assumes control of such defense and the Indemnified Party
      reasonably concludes, based on advice from counsel, that the Indemnifying Party
      and the Indemnified Party have conflicting interests with respect to such
      action, suit, proceeding or claim, the Indemnifying Party shall be responsible
      for the reasonable fees and expenses of counsel to the Indemnified Party solely
      in connection therewith; provided , however , that in no
      event shall the Indemnifying Party be responsible for the fees and expenses
      of
      more than one counsel for all Indemnified Parties. The Party controlling such
      defense shall keep the other Party advised of the status of such action, suit,
      proceeding or claim and the defense thereof and shall consider recommendations
      made by the other Party with respect thereto. The Indemnified Party shall not
      agree to any settlement of such action, suit, proceeding or claim without the
      prior written consent of the Indemnifying Party, which shall not be unreasonably
      withheld, delayed or conditioned. The Indemnifying Party shall not agree to
      any
      settlement of such action, suit, proceeding or claim or consent to any judgment
      in respect thereof that does not include a complete and unconditional release
      of
      the Indemnified Party from all liability with respect thereto or that imposes
      any liability or obligation on the Indemnified Party without the prior written
      consent of the Indemnified Party.




-33-





Section
      11.2  Governing
      Law . This
      Agreement shall be construed and the respective rights of the Parties determined
      (including the validity and applicability of the arbitration provision set
      forth
      in Section 10.3, and the conduct of any arbitration, enforcement of any arbitral
      award and any other questions of arbitration law or procedure arising
      thereunder) according to the substantive laws of the State of New York, USA,
      notwithstanding the provisions governing conflict of laws under such New York
      law to the contrary.




Section
      11.3  Assignment .
      Neither XTL nor PRESIDIO may assign this Agreement in whole or in part without
      the consent of the other, except if such assignment occurs in connection with
      the merger, sale or transfer of all or substantially all of the business and
      assets of XTL, on the one hand, or PRESIDIO, on the other, to which the subject
      matter of this Agreement pertains. Notwithstanding the foregoing, any Party
      may
      assign its rights (but not its obligations) pursuant to this Agreement in whole
      or in part to an Affiliate of such Party, provided , that the
      assigning Party shall remain primarily liable to the other Party for any breach
      of this Agreement by such Affiliate.




Section
      11.4  Entire
      Agreement; Amendments . This
      Agreement (including all exhibits and attachments hereto) constitutes the entire
      agreement between the Parties with respect to the subject matter hereof, and
      supersedes all previous arrangements with respect to the subject matter hereof,
      whether written or oral. Any amendment or modification to this Agreement shall
      be made in writing signed by both Parties.




Section
      11.5  Notices . Any
      notice required or provided for by the terms of this Agreement shall be in
      writing and shall be (a) sent by registered or certified mail, return receipt
      requested, postage prepaid, (b) sent via a reputable overnight or international
      express courier service, (c) sent by facsimile transmission, or (d) personally
      delivered, in each case properly addressed in accordance with the paragraph
      below. The effective date of notice shall be the actual date of receipt by
      the
      Party receiving the same.




Notices
      to XTL shall be addressed to:




XTL
      Biopharmaceuticals Ltd.


711
      Executive Blvd., Suite Q


Valley
      Cottage, NY 10989


Attention:
      Chief Executive Officer


Facsimil e
      No.:
      845-267-0926




with
      a
      copy to:




Goodwin
      Procter


Exchange
      Place


Boston,
      MA 02109


Attention:
      Christopher Denn


Facsimile
      No.: 617-523-1231




Notices
      to PRESIDIO shall be addressed to:




Presidio
      Pharmaceuticals, Inc.


1700
      Owens Street


Suite
      585


San
      Francisco, CA 94158


USA


Attention:
      President and Chief Executive Officer


Facsimile
      No.: 415-986-2864




with
      a
      copy to:




WilmerHale


60
      State
      Street


Boston,
      MA 02109


USA


Attention:
      David E. Redlick, Esq.


Facsimile
      No.: 617-526-5000




-34-


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




Any
      Party
      may change its address by giving notice to the other Party in the manner herein
      provided.




Section
      11.6  Force
      Majeure . No
      failure or omission by a Party in the performance of any obligation of this
      Agreement shall be deemed a breach of this Agreement or create any liability
      if
      the same shall arise from any cause or causes beyond the reasonable control
      of
      such Party, including, but not limited to, the following: acts of God; acts
      or
      omissions of any government; any rules, regulations or orders issued by any
      governmental authority or by any officer, department, agency or instrumentality
      thereof; fire; storm; flood; earthquake; accident; war; terrorism; rebellion;
      insurrection; riot; and invasion. The Party claiming force majeure shall notify
      the other Party with notice of the force majeure event as soon as practicable,
      but in no event longer than ***** business days after its occurrence, which
      notice shall reasonably identify such obligations under this Agreement and
      the
      extent to which performance thereof will be affected.




Section
      11.7  Independent
      Contractors . It is
      understood and agreed that the relationship between the Parties hereunder is
      that of independent contractors and that nothing in this Agreement shall be
      construed as authorization for either XTL or PRESIDIO to act as agent for the
      other.




Section
      11.8  No
      Strict Construction . This
      Agreement has been prepared jointly and shall not be strictly construed against
      any Party.




-35-


Section
      11.9  Headings . The
      captions or headings of the sections or other subdivisions hereof are inserted
      only as a matter of convenience or for reference and shall have no effect on
      the
      meaning of the provisions hereof.




Section
      11.10  No
      Implied Waivers; Rights Cumulative . No
      failure on the part of XTL or PRESIDIO to exercise, and no delay in exercising,
      any right, power, remedy or privilege under this Agreement, or provided by
      statute or at law or in equity or otherwise, shall impair, prejudice or
      constitute a waiver of any such right, power, remedy or privilege or be
      construed as a waiver of any breach of this Agreement or as an acquiescence
      therein, nor shall any single or partial exercise of any such right, power,
      remedy or privilege preclude any other or further exercise thereof or the
      exercise of any other right, power, remedy or privilege.




Section
      11.11  Severability . If,
      under applicable law or regulation, any provision of this Agreement is invalid
      or unenforceable, or otherwise directly or indirectly affects the validity
      of
      any other material provision(s) of this Agreement (such invalid or unenforceable
      provision, a “ Severed
      Clause ”),
      this
      Agreement shall endure except for the Severed Clause. The Parties shall consult
      one another and use reasonable efforts to agree upon a valid and enforceable
      provision that is a reasonable substitute for the Severed Clause in view of
      the
      intent of this Agreement.




Section
      11.12  Execution
      in Counterparts . This
      Agreement may be executed in counterparts, each of which counterparts, when
      so
      executed and delivered, shall be deemed to be an original, and all of which
      counterparts, taken together, shall constitute one and the same
      instrument.




Section
      11.13  No
      Third Party Beneficiaries . No
      person or entity other than XTL, PRESIDIO and their respective Affiliates and
      permitted assignees hereunder shall be deemed an intended beneficiary hereunder
      or have any right to enforce any obligation of this Agreement.




Section
      11.14  No
      Consequential Damages .
      NEITHER PARTY HERETO WILL BE LIABLE FOR INDIRECT, INCIDENTAL, CONSEQUENTIAL,
      SPECIAL, EXEMPLARY OR PUNITIVE DAMAGES ARISING OUT OF THIS AGREEMENT OR THE
      EXERCISE OF ITS RIGHTS HEREUNDER, OR FOR LOST PROFITS ARISING FROM OR RELATING
      TO ANY BREACH OF THIS AGREEMENT, REGARDLESS OF ANY NOTICE OF SUCH DAMAGES.
      NOTHING IN THIS SECTION 11.14 IS INTENDED TO LIMIT OR RESTRICT THE
      INDEMNIFICATION RIGHTS OR OBLIGATIONS OF EITHER PARTY WITH RESPECT TO THIRD
      PARTY CLAIMS.




[ *Remainder
      of This Page Intentionally Left Blank* ]




-36-


IN
      WITNESS WHEREOF, the Parties have executed this Agreement as of the Effective
      Date.




PRESIDIO
                PHARMACEUTICALS, INC.By:
            /s/
                Omar K. Haffar, Ph.D.Name:
            Omar
                K. Haffar, Ph.D.Title:
            President
                and CEOXTL
                BIOPHARMACEUTICALS LTD.By:
            /s/
                Ron BentsurName:
            Ron
                BentsurTitle:
            Chief
                Executive Officer





-37-


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




**Exhibit
      A**




**Assigned
      Contracts**




*****




*****




*****




**Copies
      of the foregoing contracts are attached hereto.**




A-1


**Exhibit
      B**




**VivoQuest
      Agreements**




**Copies
      of the VivoQuest License Agreement and the VivoQuest Asset Purchase Agreement
      are attached hereto.**




B-1


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




**Exhibit
      C**




**Series
      1, 2, 3 and 4 Compounds in XTL Database and Other
      Records**




*********




C-1


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




**Exhibit
      D**




**Series
      1 Patent Rights as of the Effective Date**


*****




D-1


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




**Exhibit
      E**




**Series
      2-4 Patent Rights as of the Effective Date**




*****


E-1


**Exhibit
      F**




**Press
      Releases**




See
      attached.




F-1


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




**Exhibit
      G**




*********




*****




*****




*****




*****




*****




G-1