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                                                                    Exhibit 10.1

                                            ***TEXT OMITTED AND FILED SEPARATELY
                                                CONFIDENTIAL TREATMENT REQUESTED


                                LICENSE AGREEMENT


                                      Effective: July 9, 2001 ("Effective Date")

         This License Agreement is by and between EPIMMUNE INC., having a
principal place of business at 5820 Nancy Ridge Drive, San Diego, CA 92121
(hereinafter referred to as "EPMN"), and GENENCOR INTERNATIONAL, INC., having a
principal place of business at 925 Page Mill Road, Palo Alto, CA 94304-1013
(hereinafter referred to as "GCOR").

         WHEREAS, the Parties have signed a certain Letter Agreement dated March
30, 2001 (the "Letter") regarding a license, research and development
collaboration in the Licensed Field (as defined) and certain equity investments
in EPMN (the "Definitive Agreements"); and

         WHEREAS, concurrent with the execution of this License Agreement the
Parties will execute such other Definitive Agreements as deemed appropriate to
conclude the contemplated transaction; and

         WHEREAS, the Parties intend for this License Agreement to constitute
the definitive license agreement.

         NOW, THEREFORE, the Parties hereby agree as follows:

                                    ARTICLE I
                                   DEFINITIONS

                  The following definitions shall control the construction of
each of the following terms wherever they appear in this Agreement:


1.1      "Affiliate" shall mean any corporation or other entity that directly,
         or indirectly through one or more intermediaries, controls, is
         controlled by, or is under common control with the designated party but
         only for so long as such relationship exists. Solely for purposes of
         this Section 1.1, "Control" shall mean ownership of fifty percent (50%)
         or greater of the shares of stock entitled to vote for directors in the
         case of a corporation and fifty percent (50%) or greater of the
         interests in profits in the case of a business entity other than a
         corporation.

1.2      "Biological License Application" ("BLA") shall mean a Biological
         License Application or equivalent application filed with the FDA or the
         equivalent application filed with regulatory authorities in other
         countries.
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1.3      "Collaboration" shall mean the program of collaborative research and
         development in the Licensed Field conducted pursuant to the
         Collaboration Agreement during the Collaboration Term as described in
         Article IX.

1.4      "Collaboration Agreement" shall mean that certain Collaboration
         Agreement between the Parties of even date herewith.

1.5      "Collaboration Patent Rights" shall mean any Sole Collaboration Patent
         Rights or Joint Collaboration Patent Rights.

1.6      "Collaboration Term" shall mean the two and one-half (2.5) year period
         from April 2, 2001 through September 1, 2003 unless extended by mutual
         agreement or terminated early as provided for in the Collaboration
         Agreement.

1.7      "Combination Product" shall mean any Licensed Product that combines
         [...***...], at least one (1) of which components is a Licensed Product
         or EPMN Product, as applicable, and at least one (1) of which
         components is not a Licensed Product or EPMN Product, as applicable,
         where either (a) [...***...] (a "Type A Combination Product"), or (b)
         [...***...] (a "Type B Combination Product"). For illustrative
         purposes, certain examples are set forth in Appendix A hereof.

1.8      "Control" shall mean, with respect to any intellectual property rights,
         the ability to grant licenses or sublicenses to and/or disclose such
         intellectual property without violating the terms of any bona fide
         agreement with a third party to which such intellectual property is
         subject.

1.9      "Date of First Commercial Sale" ("DFCS") shall mean in respect of each
         Licensed Product the first arms length transaction with a willing buyer
         for the sale of such Licensed Product into the market place by GCOR or
         any of its sublicensees.

1.10     "Diligence Period" shall mean the period commencing at the expiration
         of the Collaboration Term and continuing until the earlier of (a)
         [...***...] after the last day of the Collaboration Term, or (b) the
         date GCOR or any of its sublicensees has filed in any of the Major
         Geographies an IND for at least [...***...] Licensed Product directed
         to each Virus.


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1.11     "EPMN Know-How" shall mean any Know-How that is or may be necessary or
         useful for the development or commercialization of vaccines for
         treating or preventing diseases associated with HPV, HBV or HCV,
         including any such Know-How pertaining to the PADRE(R) Technology,
         other than any Know-How disclosed or claimed in any EPMN Patent Rights
         or Collaboration Patent Rights, which Know-How is Controlled by EPMN on
         the Effective Date or during the Collaboration Term.

1.12     "EPMN Patent Rights" shall mean Patent Rights that are useful for the
         development or commercialization of vaccines for treating or preventing
         diseases associated with HPV, HBV or HCV, including any such Patent
         Rights pertaining to the PADRE(R) Technology, which Patent Rights are
         Controlled by EPMN on the Effective Date or during the Collaboration
         Term, but excluding Collaboration Patent Rights.

1.13     "EPMN Product" shall mean a product, developed, made, used or sold by
         EPMN the manufacture, use or sale of which, but for the license granted
         in Section 2.3.2, would infringe a Valid Claim of one (1) or more Joint
         Collaboration Patent Rights.

1.14     "EPMN Technology" shall mean collectively EPMN Know-How and EPMN Patent
         Rights.

1.15     "First HPV Indication" shall mean treatment or prevention of
         [...***...].

1.16     "First Licensed Product" shall mean the first product developed by GCOR
         or any of its sublicensees for either the prevention or treatment of a
         disease associated with each Virus; provided, however, that an IND
         relating to such product has been submitted and become effective, by
         GCOR or any of its sublicensees.

1.17     "Food and Drug Administration" ("FDA") shall mean the U.S. Food and
         Drug Administration.

1.18     "HBV" shall mean Hepatitis B Virus.

1.19     "HCV" shall mean Hepatitis C Virus.

1.20     "HPV" shall mean Human Papilloma Virus.

1.21     "Investigational New Drug Application" ("IND") shall mean a request for
         authorization from the FDA or applicable regulatory authorities in
         other countries to administer an investigational drug or biological
         product to humans.

1.22     "Joint Collaboration Patent Rights" shall mean any Patent Rights
         covering inventions conceived or reduced to practice jointly by
         employees, consultants or


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         agents of EPMN and GCOR during the course of or arising from the
         Collaboration.

1.23     "Know-How" shall mean proprietary and confidential know-how, including
         technical data, experimental results, specifications, techniques,
         methods, technology, processes, recipes and written materials.

1.24     "Licensed Field" shall mean the research, development and
         commercialization of Licensed Product(s) for treating or preventing
         diseases associated with the following viruses: HPV, HBV and HCV.

1.25     "Licensed Product" shall mean a therapeutic or prophylactic vaccine (a)
         the manufacture, use or sale of which, but for any license granted to
         GCOR herein, would infringe a Valid Claim of one (1) or more EPMN
         Patent Rights or one (1) or more Collaboration Patent Rights, or (b)
         was developed or manufactured using EPMN Know-How.

1.26     "Major Geographies" shall mean [...***...].

1.27     "Net Sales" shall mean (a) with respect to a Licensed Product, the
         gross amount invoiced by GCOR or its sublicensees to unrelated third
         parties for such Licensed Product, and (b) with respect to an EPMN
         Product, the gross amount invoiced by EPMN or its sublicensees to
         unrelated third parties for such EPMN Product, in either case less:
         (i)      Trade, quantity and cash discounts actually allowed;
         (ii)     Discounts, refunds, rebates, chargebacks, retroactive price
                  adjustments, and any other allowances, which effectively
                  reduce the net selling price;
         (iii)    Actual product returns and allowances;
         (iv)     Any tariffs, duties and/or taxes (excluding withholding tax)
                  imposed on the production, sale, delivery or use of the
                  product;
         (v)      That portion of the sales value associated with
                  non-pharmaceutical drug delivery devices in an amount not to
                  exceed the fair market value of such devices, as documented in
                  writing;
         (vi)     Freight charges paid for delivery; and
         (VII)    [...***...]

         In the event the Licensed Product(s) or EPMN Product(s), as applicable,
         is sold as part of a Type A Combination Product, Net Sales for purposes
         of determining the applicable royalty for such Licensed Product(s) or
         EPMN Product(s), as applicable, shall be determined by [...***...]. In
         the event that such [...***...] cannot be determined for both the
         Licensed Product(s) or EPMN Product(s), as applicable,


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         [...***...] of the Type A Combination Product in combination, Net Sales
         of the Type A Combination Product shall be [...***...].

         In the event the Licensed Product(s) or EPMN Product(s), as applicable,
         is sold as part of a Type B Combination Product, Net Sales for purposes
         of determining the applicable royalty for such Licensed Product(s) or
         EPMN Product(s), as applicable, shall be determined by [...***...]. In
         the event that such [...***...] cannot be determined for [...***...] of
         the Type B Combination Product, Net Sales of the Type B Combination
         Product shall be [...***...].

1.28     "Non-Patented Countries" shall have the meaning set forth in Section
         3.3.

1.29     "PADRE(R) Technology" shall mean a family of immunostimulatory
         molecules which when combined with cytotoxic T cell epitopes increase
         the magnitude and duration of the immune response.

1.30     "Party" shall mean either EPMN or GCOR, as appropriate, whereas the
         term "Parties" shall mean EPMN and GCOR jointly.

1.31     "Patent Rights" shall mean all rights associated with all United States
         and foreign patents (including all reissues, extensions, confirmations,
         registrations, re-examinations, and inventor's certificates) and patent
         applications (including, without limitation, all substitutions,
         continuations, continuations-in-part, divisionals and provisionals
         thereof).

1.32     "Phase I Clinical Trial" shall mean that portion of the clinical
         development program which generally provides for the first introduction
         of a product into a small number of humans with the primary purpose of
         evaluating safety of the product and preliminary activity of the
         product, as more specifically defined by the rules and regulations of
         the FDA and corresponding rules and regulations in other countries.

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                                       5.
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1.33     "Phase III Clinical Trial" shall mean that portion of the clinical
         development program which provides for the continued trials of a
         product on sufficient numbers of patients to establish the safety and
         efficacy of a product for the desired claims and indications to provide
         adequate basis for physician labeling, as more specifically defined by
         the rules and regulations of the FDA and corresponding rules and
         regulations in other countries.

1.34     "Pivotal Trial" shall mean the clinical trial of a product (which may
         be, for example, a Phase II or Phase III trial) that is deemed by the
         FDA or appropriate regulatory agency in other countries to be
         sufficient to support the filing of a BLA or other application for
         marketing approval of such product.

1.35     "Royalty Period" shall mean, with respect to a given Licensed Product
         on a country-by-country basis, the longer of (a) [...***...] from the
         DFCS of such Licensed Product in such country, or (b) the last to
         expire EPMN Patent Right or Collaboration Patent Right licensed
         hereunder in such country.

1.36     "Second HPV Indication" shall mean treatment or prevention of
         [...***...].

1.37     "Second Licensed Product" shall mean the second product developed by or
         for GCOR or any of its sublicensees for either the prevention or
         treatment of a disease associated with each Virus; provided, however,
         that an IND relating to each product has been submitted and becomes
         effective, by GCOR or any of its sublicensees.

1.38     "Sole Collaboration Patent Rights" shall mean any Patent Rights
         covering inventions conceived or reduced to practice solely by
         employees, consultants or agents of EPMN during the course of or
         arising from the Collaboration.

1.39     "Successful Completion" shall mean a decision made by GCOR that the
         Licensed Product being evaluated in that phase of the clinical trial
         will proceed to the next phase; provided that GCOR will be deemed to
         have made a decision to proceed to the next phase with respect to a
         Licensed Product if GCOR has not notified EPMN in writing that it has
         decided not to proceed to the next phase with respect to such Licensed
         Product within [...***...] (which period may be extended by mutual
         agreement which agreement will not be unreasonably withheld) after
         completion of the statistical analysis report on "clean data" ("clean
         data" means all case report forms have been reviewed and cleaned up and
         all outstanding queries have been resolved).

1.40     "Term" shall have the meaning given such term in Section 10.1.

1.41     "Third Party License Agreements" shall mean the agreements between EPMN
         and certain third parties with respect to Third Party Technology as
         listed in Appendix B hereto.


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1.42     "Third Party Technology" shall mean collectively any Patent Rights or
         Know-How included in the EPMN Technology that are owned in whole or in
         part by a third party, licensed to EPMN and sublicensed to GCOR by EPMN
         pursuant to Section 2.2 and listed in Appendix B hereto.

1.43     "Valid Claim" shall mean any claim in (a) an unexpired patent which has
         not been held unenforceable, unpatentable or invalid by a final
         decision of a court or other governmental agency of competent
         jurisdiction from which no appeal may be or is taken, and which has not
         been admitted to be invalid or unenforceable through reissue or
         disclaimer, or (b) a pending patent application; excluding from Section
         1.43(b) (i) any patent application filed in the [...***...], any
         country in [...***...] or the [...***...] that has been pending for
         more than six (6) years following the earliest priority date of filing
         of such application, and (ii) any patent application filed in
         [...***...] that has been pending for more than eight (8) years
         following the earliest priority date of filing of such application.

1.44     "Virus" shall mean one of HPV, HBV or HCV.

                                   ARTICLE II
                                  LICENSE GRANT

2.1      Grant of License in EPMN Technology from EPMN to GCOR. EPMN hereby
         grants to GCOR and GCOR hereby accepts a worldwide, exclusive,
         royalty-bearing and sublicensable right and license to practice the
         EPMN Technology (other than the Third Party Technology) and all of
         EPMN's rights in Collaboration Patent Rights to make, have made, use,
         import, promote, market, distribute or sell Licensed Product(s) in the
         Licensed Field.

2.2      Grant of Sublicense in Third Party Technology from EPMN to GCOR.
         Subject to the terms and conditions of applicable Third Party License
         Agreements, EPMN hereby grants to GCOR and GCOR hereby accepts a
         worldwide, exclusive or non-exclusive (as the case may be),
         royalty-bearing and sublicensable (subject to the terms of the Third
         Party License Agreement) right and license to practice the Third Party
         Technology to make, have made, use, import, promote, market, distribute
         or sell Licensed Product(s) in the Licensed Field.

2.3      Grant of License to Joint Collaboration Patent Rights Outside the
         Licensed Field.

         2.3.1 EPMN Grant. EPMN hereby grants to GCOR and GCOR hereby accepts a
         worldwide, non-exclusive, [...***...] and sublicenseable right and
         license to practice EPMN's rights in Joint Collaboration Patent Rights
         to make, have made, import, promote, market, distribute or sell
         products or processes outside the Licensed Field.

         2.3.2 GCOR Grant. GCOR hereby grants to EPMN and EPMN hereby accepts a
         worldwide, non-exclusive, [...***...] and sublicenseable right and
         license to practice GCOR's rights in Joint Collaboration Patent Rights
         to make, have made,


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         import, promote, market, distribute or sell EPMN Products outside the
         Licensed Field.


                                   ARTICLE III
                           UPFRONT FEES AND ROYALTIES

3.1      License Fee. Upon the Effective Date, GCOR shall pay EPMN a lump sum
         payment of [...***...]. Such payment shall be non-creditable and
         non-refundable.

3.2      GCOR Royalty Rates. Subject to Sections 3.2.1, 3.2.2, 3.2.3 and 3.2.4
         hereof, GCOR shall during the Royalty Period pay EPMN a royalty of
         [...***...] of Net Sales of Licensed Product.

         3.2.1 Third Party Technology Sublicense. In addition to the royalty
         rate set forth above, GCOR will make any royalty payments due to a
         third party under any Third Party License Agreement due to the sale of
         Licensed Product; provided that GCOR will be entitled to credit
         [...***...] of any such third party royalty payments under such Third
         Party License Agreement against the earned royalties due to EPMN
         hereunder. EPMN shall be solely responsible for any other payment due
         under any Third Party License Agreement. [...***...].

         3.2.2 Royalty Credits. If total royalty payments made by GCOR to make,
         have made, import, use or sell a Licensed Product (including all
         royalties paid to non-Affiliated third parties, royalties paid to third
         parties based on Third Party License Agreements, and royalties paid to
         EPMN) exceed [...***...] of Net Sales of such Licensed Product in a
         given calendar quarter, then GCOR shall have the right to credit
         [...***...] of the amount by which such total royalty payments in such
         quarter exceed [...***...] of Net Sales of such Licensed Product in
         such quarter against the earned royalties due to EPMN hereunder;
         provided that this Section 3.2.2 shall not apply to any Licensed
         Product that is a Combination Product. For illustrative purposes,
         certain royalty calculation scenarios are set forth in Appendix C
         hereof.

         3.2.3 Minimum Royalty. Except as provided in Section 3.2.4, in no event
         will royalties payable to EPMN as a result of royalty credits under
         this Section 3.2 be less than [...***...] of Net Sales of Licensed
         Product.

         3.2.4 HCV. In the event GCOR must obtain a license from [...***...] (or
         its successor in interest) to Patent Rights in order to commercialize
         an HCV Licensed Product, EPMN's minimum royalty as result of royalty
         credits under this Section 3.2 will be reduced to [...***...] of Net
         Sales of such HCV Licensed Product.

3.3      Sales in Non-Patented Countries. In the event EPMN Patent Rights or
         Collaboration Patent Rights cover the manufacture, use or sale of a
         Licensed


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                                       8.
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         Product in the Major Geographies, then in any other geography where
         GCOR or any of its sublicensees sells such Licensed Product but where
         no EPMN Patent Rights or Collaboration Patent Rights cover the
         manufacture, use or sale of such Licensed Product (the "Non-Patented
         Countries"), and subject to permissible credits pursuant to Section 3.2
         above, the applicable royalty on Net Sales of Licensed Product in the
         Non-Patented Countries will be [...***...] of The applicable royalty
         payable on Net Sales of such Licensed Product in the Major Geographies,
         subject to further reduction in the Non-Patented Countries as mutually
         agreed by the Parties in writing in the event of [...***...]. For
         illustrative purposes only, if EPMN or Collaboration Patent Rights
         covering the manufacture, use or sale of a Licensed Product exist in
         the [...***...] but not in [...***...] and GCOR sells the Licensed
         Product in [...***...], [...***...] is a Non-Patented Country and
         applicable royalties payable on Net Sales in [...***...] will be
         determined according to this Section 3.3.

3.4      Minimum Annual Royalty. Following the Date of First Commercial Sale of
         a Licensed Product in a country within the Major Geographies and during
         the Royalty Period, GCOR will pay EPMN a minimum royalty of [...***...]
         per calendar year (the "Minimum Annual Royalty"); provided that actual
         earned royalties paid To EPMN pursuant to Section 3.2 above in a given
         calendar year shall be credited against the Minimum Annual Royalty for
         such calendar year.

3.5      [...***...]

                                   ARTICLE IV
                      PAYMENT AND ACCOUNTING FOR ROYALTIES

4.1      Keeping of Records. Each Party shall keep, and impose on its
         sublicensees to keep, complete and correct records of Net Sales of
         Licensed Products or EPMN Product for a period of three (3) years from
         the making of a royalty payment with respect to such Net Sales under
         this Agreement.

4.2      Payment Term. All royalty payments (other than the Minimum Annual
         Royalty) under this Agreement shall become due and payable [...***...]
         after the last day of the [...***...] in which the corresponding sales
         of Licensed Product or EPMN Product were made. Payment shall be
         accompanied by a report on a country-by-country basis, showing the
         gross receipts from sales of Licensed Product or EPMN Product less the
         deductions permitted in Section 1.27 and the resulting calculation of
         the Net Sales used in the computation of the royalty payments.

         4.2.1 Minimum Annual Royalty. Notwithstanding the above provision
         relating to [...***...] royalty payments, the Minimum Annual Royalty
         payments by GCOR will be due and payable only at the end of each
         calendar year period in which corresponding sales of Licensed Product
         were made. For any calendar year period, if the earned royalties paid
         to EPMN in such period are less than the Minimum Annual Royalty payment
         set forth above in Section 3.4, GCOR will


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                                       9.
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         within [...***...] of the end of the relevant calendar year period, pay
         EPMN the difference.

4.3      Currency and Exchange Rate. Payments under this Agreement will be made
         in U.S. Dollars by wire transfer to a bank account to be designated by
         the receiving Party. Net Sales in currency other than U.S. Dollars
         shall be converted into Net Sales in U.S. Dollars on a monthly basis
         using the rate of exchange as quoted by the Wall Street Journal
         (Eastern Edition) on the last business day of the applicable month in
         which the corresponding sales of Licensed Products or EPMN Products
         were made.

4.4      Audit of Records. Each Party will allow the other to appoint a firm of
         independent certified public accountants to whom the non-appointing
         Party has no reasonable objection. The non-appointing Party shall give
         such accountants access, during ordinary business hours and subject to
         reasonable advance notice, to such records as are necessary to verify
         the accuracy of any royalty payments made or payable under this
         Agreement for a period covering not more than the preceding one (1)
         year. Such access shall be granted no more than once in a calendar
         year, at the requesting Party's expense. The independent certified
         public accountants shall be under a confidentiality obligation to the
         non-appointing Party to disclose to the appointing Party in its report
         only the amount of royalties payable under this Agreement. In the event
         it is determined that the records indicate that the amount of royalties
         payable under this Agreement by the non-appointing Party is more than
         the amount actually paid, the non-appointing Party shall pay such
         difference within [...***...] of such accountant's report (together
         wIth any interest thereon pursuant to Section 4.5), and if that
         difference is greater than [...***...] of the amounts actually paid,
         then the costs and expenses of said independent certified public
         accountants shall be borne by the non-appointing Party.

4.5      Late Payments. In the event that any payment due hereunder is not made
         when due, the payment shall accrue interest from the date due at the
         rate of [...***...]; provided, however, that in no event shall sUch
         rate exceed the maximum legal annual interest rate. The payment of such
         interest shall not limit a Party from exercising any other rights it
         may have as a consequence of the lateness of any payment.

4.6      Withholding. Any withholding of taxes levied by tax authorities on the
         payments hereunder shall be borne by the Party receiving the payment
         and deducted by the Party making the payment from the sums otherwise
         payable by it hereunder for payment to the proper tax authorities on
         behalf of the Party receiving the payment. The Party making the payment
         agrees to cooperate with the Party receiving the payment in the event
         that the receiving Party claims exemption from such withholding or
         seeks credits or deductions under any double taxation or similar treaty
         or agreement from time to time in force, such cooperation to consist of
         providing receipts of payment of such withheld tax or other documents
         reasonably available to the Party making the payment.


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                                    ARTICLE V
                               MILESTONE PAYMENTS

5.1      Commercial Milestones for the First Licensed Product. During the Term
         and subject to Section 5.6 below, GCOR will pay EPMN certain milestone
         payments (the "Milestone Payments") for the First Licensed Product
         developed for each Virus within the Licensed Field as detailed below:

         5.1.1 Effective IND. [...***...] after an IND covering the First
         Licensed Product for a Virus has become effective, GCOR shall pay EPMN
         [...***...]; provided that, if there is a clinical hold with respect to
         such IND at the time that such payment becomes due, such payment shall
         instead be due and payable when such clinical hold is lifted.

         5.1.2 Completion of Phase I. Within [...***...] after Successful
         Completion of the first Phase I Clinical Trial for the First Licensed
         Product for a Virus, GCOR shall pay EPMN [...***...];

         5.1.3 Initiation of Pivotal Trial. Upon treatment of the first patient
         in the first Pivotal Trial for the First Licensed Product for a Virus,
         GCOR shall pay EPMN [...***...];

         5.1.4 Completion of Phase III. Within [...***...] after Successful
         Completion of the first Phase III Clinical Trial for the First Licensed
         Product for a Virus, GCOR shall pay EPMN [...***...];

         5.1.5 Submission of BLA. Within [...***...] from the submission of the
         first BLA covering the First Licensed Product for a Virus, GCOR shall
         pay EPMN [...***...];

         5.1.6 Approval. Within [...***...] from written marketing approval of
         the First Licensed Product for a Virus in the geographic market
         designated below by the appropriate regulatory agency, GCOR shall pay
         EPMN the following payments:

                  5.1.6.1  For approval to market in the [...***...], GCOR shall
                  pay EPMN [...***...];

                  5.1.6.2  For approval to market in [...***...] or in the first
                  of any of [...***...], GCOR shall pay EPMN [...***...];

                  5.1.6.3  For approval to market in [...***...], GCOR shall pay
                  EPMN [...***...].

5.2      Commercial Milestones for a Second Licensed Product. Except as set
         forth in Section 5.3 for a Licensed Product useful against the Second
         HPV Indication, during the Term, GCOR will pay EPMN certain additional
         milestone payments (the "Additional Milestone Payments") for any Second
         Licensed Product developed for each Virus within the Licensed Field as
         detailed below:


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         5.2.1 Second Licensed Product requiring new IND. For a Second Licensed
         Product, which requires the filing of a new IND, GCOR shall pay EPMN
         Additional Milestone Payments equal to [...***...] of each of the
         MilestonE Payments set forth above in Sections 5.1.1 through 5.1.6 upon
         achievement of the indicated milestone-triggering event. For the
         avoidance of doubt, if the Second Licensed Product does not require the
         filing of a new IND for clinical evaluation, approval or marketing such
         as for example, Second Licensed Products, which are line extensions,
         formulation changes, expanded labeling or the like, GCOR shall pay EPMN
         no Additional Milestone Payments.

5.3      Second HPV Indication Milestones. In the event GCOR or any of its
         sublicensees develops a Licensed Product for treatment or prevention of
         the Second HPV Indication (the "Second HPV Product"), which Second HPV
         Product requires the filing of a new IND, GCOR shall pay EPMN
         Additional Milestone Payments equal to [...***...] of each of the
         Milestone Payments set forth above in Sections 5.1.1 through 5.1.6 upON
         achievement of the indicated milestone-triggering event.

5.4      Discontinued Development. In the event GCOR or any of its sublicensees
         develops a Licensed Product for a Virus as a replacement for the First
         Licensed Product or Second Licensed Product for such Virus after
         development of such First Licensed Product or Second Licensed Product,
         as applicable, has been discontinued, such Licensed Product shall be
         deemed a replacement First Licensed Product (if it replaces a First
         Licensed Product) or replacement Second Licensed Product (if it
         replaces a Second Licensed Product), as applicable; provided that GCOR
         shall pay EPMN only those Milestone Payments for a replacement First
         Licensed Product or Additional Milestone Payments for a replacement
         Second Licensed Product, as applicable, set forth in Sections 5.1.4
         through 5.1.6 upon achievement of the indicated milestone-triggering
         event.

5.5      Know-How Based Licensed Product Milestones. In the event GCOR or any of
         its sublicensees develops a Licensed Product and no EPMN Patent Rights
         or Collaboration Patent Rights cover the manufacture, use or sale of
         such Licensed Product but EPMN Know-How is used in the development or
         manufacture of such Licensed Product, GCOR shall pay EPMN [...***...]
         of each of the Milestone Payments or Additional MilestoNE Payments that
         would otherwise be payable under this Article V.

5.6      Location of Occurrence of Milestone Events. If a milestone-triggering
         event under this Article V (other than Section 5.1.6 or any provision
         based upon Section 5.1.6) first occurs (a) in any of the Major
         Geographies, then one hundred percent (100%) of the applicable
         Milestone Payment or Additional Milestone Payment determined in
         accordance with the applicable provision of Article V shall be due and
         payable in connection with the occurrence of such milestone-triggering
         event, and (b) in any country other than any of the Major


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         Geographies, then [...***...] of the applicable Milestone Payment or
         Additional Milestone Payment determined in accordance with the
         applicable provision of Article V shall be due and payable upon the
         occurrence of such milestone-triggering event, and the remaining
         [...***...] of the applicable Milestone Payment or Additional Milestone
         Payment determined in accordance with the applicable provision of
         Article V shall be due and payable upon the occurrence of such
         milestone-triggering event in any of the Major Geographies.

                                   ARTICLE VI
                                DILIGENT EFFORTS

6.1      Diligence. During the Diligence Period GCOR and its sublicensees will
         use commercially reasonable efforts to develop Licensed Products. As
         used herein "commercially reasonable efforts" means, unless the Parties
         agree otherwise, those efforts consistent with the exercise of prudent
         scientific and business judgment, as applied to other products of
         similar scientific and commercial potential. Specifically, the Parties
         agree that GCOR will have used commercially reasonable efforts during
         the Diligence Period if GCOR continues to invest, internally or
         otherwise (including Milestone Payments paid hereunder), a minimum of
         [...***...] as may be reduced pursuant to Section 6.2 hereof
         ("Investment Commitment") for the development of Licensed Products.
         GCOR will provide to EPMN on each [...***...] durING the Diligence
         Period a report describing GCOR and its sublicensees' investment in
         developing Licensed Products in sufficient detail for EPMN to determine
         whether the Investment Commitment is being satisfied. [...***...],
         during the Diligence Period, upon request by EPMN, GCOR will provide to
         EPMN a general report on the development status of Licensed Products,
         including for example, information on where a Licensed Product is in
         research or pre-clinical development or whether an IND has been filed
         and the like.

6.2      IND Filing. In the event GCOR or its sublicensee files an IND at any
         time during the Collaboration Term or the Diligence Period on
         [...***...] or more Licensed Product(s), the Investment Commitment will
         be reduced by [...***...] for each IND filed. Accordingly the
         Investment Commitment will be reduced by [...***...] upon filing of the
         first IND, [...***...] upon filing of a second IND and [...***...] upon
         filing of a thIRD IND filed by GCOR or its sublicensee.

6.3      Remedy. If (i) during the Diligence Period GCOR has failed to maintain
         the relevant Investment Commitment, or otherwise use commercially
         reasonable efforts to develop Licensed Products, or (ii) by the end of
         the Diligence Period, neither GCOR nor any of its sublicensees has
         filed in any of the Major Geographies an IND for at least [...***...]
         Licensed [...***...] in an Affected Program (as defined in SeCTION 6.4
         below), EPMN shall have the right, subject to Section 6.4, in its sole
         discretion to (a) reduce GCOR's exclusive license in the Affected
         Program to a non-exclusive license, or (b) terminate GCOR's license as
         to the Affected Program, unless, in either case, GCOR provides evidence


                                               *CONFIDENTIAL TREATMENT REQUESTED
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         reasonably satisfactory to EPMN that such failure was beyond its
         control. If GCOR or any of its sublicensees has filed an IND for a
         Licensed Product in an Affected Program in any geography other than one
         of the Major Geographies prior to the end of the Diligence Period, EPMN
         may only exercise the remedy provided under this Section 6.3 with
         regard to the license in the Affected Program outside that geography,
         and within that geography GCOR shall maintain its exclusive license
         subject to the terms and conditions of this Agreement.

6.4      Notice of Lack of Diligence. EPMN shall give GCOR written notice of its
         intention to reduce the license to a non-exclusive license or to
         terminate the license for lack of diligence. Such notice shall include
         an indication by EPMN whether the alleged failure relates to the lack
         of development of a Licensed Product for [...***...] or more of the
         HPV, HCV or HBV programs (the "Affected Program(s)") and the evideNCE
         on which EPMN bases its opinion. GCOR and its sublicensees shall have
         [...***...] (which period shall be IN place of, and not in addition to,
         the period under Section 10.2) to cure the deficiency or to provide
         reasons satisfactory to EPMN for their inability to do so. Should EPMN
         reduce GCOR's exclusive license in an Affected Program to a
         non-exclusive license, GCOR shall have no further obligation under
         Article V of this Agreement and GCOR's royalty obligation upon
         commercialization of a Licensed Product from the Affected Program shall
         be reduced to [...***...] of Net Sales under Section 3.2 (and the
         provisions of Section 3.2.1, 3.2.2 and 3.2.3 shall no longer apply).
         Should EPMN terminate GCOR's exclusive license in an Affected Program,
         the provisions of Section 10.5.2 shall apply.

                                   ARTICLE VII
                         REPRESENTATIONS AND WARRANTIES

7.1      By EPMN. EPMN represents and warrants to GCOR that:

         7.1.1 Corporate Power. As of the Effective Date, EPMN is duly organized
         and validly existing under the laws of Delaware and has full corporate
         power and authority to enter into this Agreement and carry out the
         provisions hereof;

         7.1.2 Due Authorization. As of the Effective Date, EPMN is duly
         authorized to execute and deliver this Agreement and to perform its
         obligations hereunder. The person executing this Agreement on EPMN's
         behalf has been duly authorized to do so by all requisite corporate
         action;

         7.1.3 Binding Agreement. This Agreement is a legal and valid obligation
         binding upon EPMN and enforceable in accordance with its terms. As of
         the Effective Date, the execution, delivery and performance of this
         Agreement by EPMN does not conflict with any agreement, instrument or
         understanding, oral or written, to which it is a party or by which it
         may be bound, nor violate any material law or regulation of any court,
         governmental body or administrative or other agency having jurisdiction
         over it;


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         7.1.4 Technology Ownership. EPMN owns the EPMN Technology (other than
         the Third Party Technology) and has the right to grant to GCOR the
         exclusive license granted under Section 2.1 hereof and that said
         license does not conflict with or violate the terms of any agreement
         between EPMN and any third party;

         7.1.5 Third Party Technology. Appendix B is a true and complete list of
         all Third Party Technology Controlled by EPMN as of the Effective Date
         which is sublicenseable to GCOR in the Licensed Field; EPMN has
         disclosed to GCOR all the terms and conditions relating to EPMN's
         rights in said Third Party Technology; EPMN has the right to grant to
         GCOR the sublicense in said Third Party Technology granted under
         Section 2.2 hereof; and said sublicense does not conflict with or
         violate the terms of any agreement between EPMN and any third party;

         7.1.6 Validity. As of the Effective Date, EPMN is aware of no action,
         suit or inquiry or investigation instituted by any federal or state
         governmental agency which questions the validity of this Agreement;

         7.1.7 Proceedings. EPMN has duly informed GCOR of administrative or
         judicial proceedings, if any, contesting the inventorship, ownership,
         validity or enforceability of any element of the EPMN Technology;

         7.1.8 Prior Agreement. EPMN has not, as of the Effective Date, licensed
         the EPMN Technology to any third party in the Licensed Field;

         7.1.9 Disclosure. As of the Effective Date, EPMN has no third party
         agreements which would be violated by the disclosure to GCOR of EPMN
         Know-How;

         7.1.10 Non-Infringement. As of the Effective Date, to EPMN's knowledge,
         the practice of EPMN Technology to develop or commercialize Licensed
         Products does not infringe any Patent Rights of any third party nor has
         EPMN received any notice of any alleged infringement of or conflict
         with Patent Rights of any third party arising from the practice of EPMN
         Technology.

7.2      By GCOR. GCOR represents and warrants to EPMN that:

         7.2.1 Corporate Power. As of the Effective Date, GCOR is duly organized
         and validly existing under the laws of Delaware and has full corporate
         power and authority to enter into this Agreement and carry out the
         provisions hereof;

         7.2.2 Due Authorization. As of the Effective Date, GCOR is duly
         authorized to execute and deliver this Agreement and to perform its
         obligations hereunder. The person executing this Agreement on GCOR's
         behalf has been duly authorized to do so by all requisite corporate
         action;


                                      15.
<PAGE>
         7.2.3 Binding Agreement. This Agreement is a legal and valid obligation
         binding upon GCOR and enforceable in accordance with its terms. As of
         the Effective Date, the execution, delivery and performance of this
         Agreement by GCOR does not conflict with any agreement, instrument or
         understanding, oral or written, to which it is a party or by which it
         may be bound, nor violate any material law or regulation of any court,
         governmental body or administrative or other agency having jurisdiction
         over it;

         7.2.4 Validity. As of the Effective Date, GCOR is aware of no action,
         suit or inquiry or investigation instituted by any federal or state
         governmental agency which questions the validity of this Agreement.

7.3      Disclaimer. NEITHER PARTY GUARANTEES THE SAFETY OR USEFULNESS OF ANY
         PRODUCT. EXCEPT AS EXPRESSLY SET FORTH IN THIS AGREEMENT, THE
         COLLABORATION AGREEMENT OR THE SECURITIES PURCHASE AGREEMENT, NEITHER
         PARTY MAKES ANY REPRESENTATION OR WARRANTY TO THE OTHER PARTY OF ANY
         NATURE, EXPRESS OR IMPLIED, INCLUDING, WITHOUT LIMITATION, ANY WARRANTY
         OF NONINFRINGEMENT, MERCHANTABILITY OR FITNESS FOR A PARTICULAR
         PURPOSE.

                                  ARTICLE VIII
                         PATENT PROSECUTION/ENFORCEMENT

8.1      Prosecution of EPMN Patent Rights. Subject to the terms of any Third
         Party License Agreement with respect to the Third Party Technology,
         EPMN will be responsible for filing, prosecuting and maintaining, at
         its own expense, all patents and patent applications included in the
         EPMN Patent Rights. EPMN shall routinely and at least [...***...]
         provide GCOR with information on the status of said EPMN Patent Rights
         including reports on the prosecution and issuance of the EPMN Patent
         Rights. To the extent practicable and subject to the terms of any Third
         Party License Agreement with respect to the Third Party Technology, for
         so long as GCOR maintains an exclusive license under this Agreement,
         EPMN will provide GCOR an opportunity to discuss and will consider in
         good faith GCOR's suggestions regarding major prosecution events with
         respect to the exclusively licensed EPMN Patent Rights. Such major
         prosecution events shall include substantive amendments to claims,
         response to final rejections and notices of allowance, filing decisions
         in the US as well as foreign patent offices, oppositions, revocations,
         re-examination or other substantive prosecution matters with respect to
         the EPMN Patent Rights. In the event that EPMN desires to abandon any
         patent application or patent included within the EPMN Patent Rights,
         and if GCOR then has an exclusive license to the relevant EPMN Patent
         Rights, EPMN shall provide reasonable prior written notice to GCOR of
         such intention to abandon, and at GCOR's request assign or otherwise
         transfer to GCOR all of EPMN's right, title and interest in and to the
         EPMN Patent Rights


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         designated in such notice and shall execute all documents necessary to
         effect such assignment or transfer.

8.2      Enforcement of EPMN Patent Rights and Collaboration Patent Rights.

         8.2.1 Notice. In the event that either Party becomes aware of any
         alleged or threatened infringement of any EPMN Patent Rights or
         Collaboration Patent Right by any third party, it shall provide the
         other Party with written notice of and evidence establishing such
         infringement. The Parties agree to cooperate in taking commercially
         reasonable legal action to protect the commercial interests of the
         Parties in the applicable EPMN Patent Rights or Collaboration Patent
         Rights against infringement by third parties.

         8.2.2 GCOR Enforcement Within the Licensed Field. In the event that
         either Party provides the other with written notice of and evidence
         establishing infringement of an EPMN Patent Right or Collaboration
         Patent Right by a third party with a product made, used or sold in the
         Licensed Field, the Parties shall promptly meet and agree on the
         necessary action to abate such infringement. Principally, for
         infringing conduct within the Licensed Field if GCOR then has an
         exclusive license as to the allegedly infringed Patent Rights under
         this Agreement, GCOR shall take the lead role and absent agreement to
         the contrary shall have the first right to take any necessary action
         against such infringement or alleged infringement. In no event will
         either Party take action to enforce a Joint Collaboration Patent
         without the consent of the other Party. If GCOR elects to take action
         against such infringement alone or if the Parties agree to take such
         action together, both Parties shall render all reasonable assistance to
         the enforcing party in connection therewith including being named as a
         party, if necessary. In such an event, each party shall have the right
         to be represented in that action by counsel of its own choice and at
         its expense. If GCOR fails to bring an action or proceeding with
         respect to any infringement of EPMN Patent Rights or Sole Collaboration
         Patent Rights under this Section 8.2.2 within (i) [...***...] followiNG
         the notice of alleged infringement or (ii) [...***...] before the time
         limit, if any, set forth in the appropriate laws and regulations for
         the filing of such actions, whichever comes first, EPMN shall have the
         right to take any action necessary against such infringement or alleged
         infringement. In such event, GCOR shall have the right to be
         represented by counsel of its own choice and at its expense. In no
         event shall either Party settle or abate such infringement pursuant to
         this Section 8.2.2 in a manner that would diminish the rights or
         interests of the other Party or obligate the other Party to make any
         payment or take any action without written approval of such other
         Party. Except as otherwise agreed to by the Parties as part of a
         cost-sharing arrangement, any recovery realized as a result of such
         action involving any EPMN Patent Rights or Collaboration Patent Rights
         under this Section 8.2.2, after reimbursement of any litigation
         expenses of the Parties, shall [...***...]. With respect to any
         recovery received by GCOR, to the extent compensatory damages are
         awarded based on


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         lost sales, such lost sales damages (unless otherwise shared with EPMN)
         shall be treated as Net Sales for purposes of the royalty provisions of
         this Agreement.

         8.2.3 Enforcement by EPMN. In the event that either Party provides the
         other with written notice of infringement of an EPMN Patent Right or
         Sole Collaboration Patent Rights (a) by a third party with a product
         made, used or sold outside the Licensed Field, or (b) by a third party
         with a product made, used or sold in the Licensed Field if GCOR's
         exclusive license as to the allegedly infringed Patent Rights has been
         reduced to a non-exclusive license pursuant to Section 6.3, EPMN shall
         have the sole right, at its sole discretion, to take any necessary
         action against such infringement or alleged infringement. EPMN will
         keep GCOR informed of the status of any action arising from such
         infringement and to the extent permissible allow GCOR to be a party in
         such proceeding, represented by its own counsel at its own cost. Any
         recovery realized as a result of such action involving any EPMN Patent
         Rights or Sole Collaboration Patent Rights under this Section 8.2.3,
         after reimbursement of any litigation expenses of the Parties, shall
         [...***...]. In no event may EPMN settle or abate such infringement
         under EPMN Patent Rights or Sole Collaboration Patent Rights outside
         the Licensed Field in a manner which would diminish the rights or
         interests of GCOR within the Licensed Field, except with GCOR's written
         consent, which shall not be unreasonably withheld.

         8.2.4 Joint Collaboration Patent Rights. In no event will either Party
         take action to enforce a Joint Collaboration Patent without the written
         consent of the other Party.

8.3      Defense of Third Party Infringement Claim. Each Party shall promptly
         notify the other Party of any suit, claim or demand based on actual or
         alleged infringement of a third party Patent Right through the making,
         having made, using, selling, offering for sale or importing of Licensed
         Products by GCOR or its sublicensees. GCOR shall have the first right
         to defend such suit at its own cost, and EPMN shall have the right to
         be represented in that action by counsel of its own choice and at
         EPMN's expense. In the event such suit, claim or demand is determined
         to arise from a material breach of any EPMN representation and
         warranty, EPMN shall indemnify GCOR pursuant to Article XII. EPMN will
         provide reasonable and necessary assistance in any defense undertaken
         by GCOR, at GCOR's expense. The Parties shall keep one another informed
         of the status of any of their respective activities regarding any
         litigation concerning the foregoing. Neither Party shall have the right
         to settle any patent infringement action under this Section 8.3 in a
         manner that would diminish the rights or interests of the other Party
         or obligate the other Party to make any payment or take any action
         without written approval of such other Party.

8.4      Royalty Payments During any Third Party Infringement Claims. During the
         pendency of any suit, claim or demand alleging infringement of a third
         party Patent Right through the making, having made, using, selling,
         offering for sale or


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         importing of Licensed Product by GCOR or its sublicensees, if GCOR and
         its sublicensees are required to cease making, having made, using,
         selling, offering for sale or importing of Licensed Product and
         provided that such suit, claim or demand is not attributable to the
         practice of Patent Rights or Know-How other than the EPMN Patent Rights
         and EPMN Know-How, GCOR's royalty payments due under this Agreement for
         sale of the relevant Licensed Product shall be stayed until sales
         resume (if at all). If GCOR and its sublicensees are not required to
         cease the making, having made, using, selling, offering for sale or
         importing of Licensed Product during the pendency of any such suit,
         claim or demand, GCOR shall pay applicable royalty payments on Net
         Sales of Licensed Product to EPMN in accordance with the terms of this
         Agreement. In the event a final unappealable judgment with respect to
         such suit, claim or demand requires GCOR or its sublicensees to pay to
         any third party damages based on sales of Licensed Products on which
         royalty payments were made to EPMN pursuant to the preceding sentence,
         then EPMN shall return to GCOR the amount of such royalty payments made
         that were based on such sales of Licensed Products, together with
         interest thereon in accordance with Section 4.5.

                                   ARTICLE IX
                                  COLLABORATION

9.1      Collaboration Agreement. Concurrently herewith, the Parties have
         concluded a Collaboration Agreement including the Work Plan detailing
         the efforts to be undertaken pursuant to the Collaboration Agreement.
         All Collaboration Patent Rights shall be licensed in accordance with
         the terms of this Agreement.

                                    ARTICLE X
                              TERM AND TERMINATION

10.1     Term. This Agreement shall become effective on the Effective Date and
         shall expire at the end of the last Royalty Period for any Licensed
         Product, unless earlier terminated under Section 10.2, 10.3 or 10.4
         (the "Term"); provided that the licenses granted under Section 2.3 and
         the royalty provisions of Section 3.5 and any other provisions to the
         extent that they pertain to such licenses or royalty provisions shall
         become effective on the Effective Date and shall expire upon expiration
         of the last to expire of the Joint Collaboration Patent Rights, unless
         earlier terminated under Section 10.2, 10.3 or 10.4.

10.2     Termination Due to Material Breach. If a Party to this Agreement
         commits a material breach of any provision of this Agreement (including
         but not limited to payment due under Article III or V, diligence under
         Article VI, warranties under Article VII, Patent Prosecution,
         Enforcement or Defense under Article VIII or Confidentiality under
         Article XI) and fails to remedy such breach within [...***...] with
         respect to breach of any payment obligation) after written notice
         thereof from the other Party stating the intent to terminate, the Party
         not in default may, at its option, terminate this Agreement by giving
         written notice to the Party in default.


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10.3     Termination due to Bankruptcy. In the event that a Party becomes
         subject to bankruptcy, insolvency, liquidation or similar proceedings,
         the other Party shall be entitled to terminate this Agreement upon
         written notice to such Party.

10.4     Termination by Licensee. Either Party may terminate this Agreement with
         respect to the licenses granted hereunder to such Party at any time
         after the expiration or termination of the Collaboration Term upon
         [...***...] prior written notice to the other Party.

10.5     Effect of Termination; Survival of Provisions.

         10.5.1 Termination by EPMN. Upon termination of this Agreement by EPMN
         pursuant to Section 10.2 or 10.3 or termination by GCOR pursuant to
         Section 10.4: (i) all rights under the licenses granted by EPMN to GCOR
         hereunder shall automatically terminate and revert to EPMN except that
         GCOR shall have the right to sell off any existing inventory of
         Licensed Product subject to its obligations to pay applicable royalties
         as provided in Article III; (ii) any permitted sublicenses granted
         hereunder by GCOR shall remain in effect, but shall be assigned to
         EPMN; (iii) the licenses granted by GCOR to EPMN hereunder shall remain
         in effect in accordance with their terms, subject to compliance by EPMN
         with all applicable provisions of this Agreement; and (iv) GCOR shall,
         upon request by EPMN, deliver to EPMN any and all confidential
         information of EPMN then in its possession.

         10.5.2 Termination as to Affected Program. Upon termination of this
         Agreement by EPMN as to one (1) or more Affected Program in any
         geographies pursuant to Section 6.3(b): (i) all rights under the
         licenses granted by EPMN to GCOR hereunder as to the Affected
         Program(s) in such geographies shall automatically terminate and revert
         to EPMN; (ii) any permitted sublicenses granted hereunder by GCOR in
         the Affected Program(s) in such geographies shall remain in effect, but
         shall be assigned to EPMN; (iii) the licenses granted by EPMN to GCOR
         hereunder other than those described in Section 10.5.2(i) shall remain
         in effect in accordance with their terms, subject to compliance by GCOR
         with all applicable provisions of this Agreement; (iv) the licenses
         granted by GCOR to EPMN hereunder shall remain in effect in accordance
         with their terms, subject to compliance by EPMN with all applicable
         provisions of this Agreement; and (v) GCOR shall, upon request by EPMN,
         deliver to EPMN any and all confidential information of EPMN with
         respect to the Affected Program(s) then in its possession, except to
         the extent needed in connection with any licenses remaining in effect
         as described in Section 10.5.2(iii).

         10.5.3 Termination by GCOR. Upon termination of this Agreement by GCOR
         pursuant to Section 10.2 or 10.3 or termination by EPMN pursuant to
         Section 10.4: (i) all rights under the licenses granted by GCOR to EPMN
         hereunder shall automatically terminate and revert to GCOR; (ii) any
         permitted


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         sublicenses granted hereunder by EPMN shall remain in effect, but shall
         be assigned to GCOR; (iii) the licenses granted by EPMN to GCOR
         hereunder shall remain in effect in accordance with their terms,
         subject to compliance by GCOR with all applicable provisions of this
         Agreement; and (iv) EPMN shall upon request by GCOR, deliver to GCOR
         any and all confidential information of GCOR then in its possession.

         10.5.4 Survival. Expiration or termination of this Agreement shall not
         terminate any obligation of either Party to the other Party, including
         any payment obligation, that has accrued prior to the date of
         expiration or termination. The provisions contained in Sections 4.1,
         4.4, 7.3, 10.5, 11.1 and 11.2 and Articles I, XII and XIII of this
         Agreement shall survive its expiration or earlier termination.

         10.5.5 Remedies. In the event of any breach of any provision of this
         Agreement, in addition to the termination rights set forth herein, each
         Party shall have all other rights and remedies at law or equity to
         enforce this Agreement.

                                   ARTICLE XI
                                 CONFIDENTIALITY

11.1     Confidentiality Obligation. In consideration of disclosure by either
         Party (the "disclosing Party") to the other (the "Recipient") of
         confidential information in written or oral form or in the form of
         samples, the Recipient and the Recipient's Affiliates undertake for a
         period of [...***...] from the end OF the Term to treat received
         confidential information as confidential and therefore not to disclose
         it to any third party except as permitted hereunder and to use such
         confidential information only for the purposes of this Agreement. Each
         Recipient will use at least the same standard of care as it uses to
         protect proprietary or confidential information of its own to ensure
         that its employees, agents, consultants and other representatives do
         not disclose or make any unauthorized use of the confidential
         information of the disclosing Party. Each Recipient will promptly
         notify the other upon discovery of any unauthorized disclosure of the
         confidential information of the disclosing Party. This obligation does
         not apply to:

                  (a) information which, at the time of disclosure, is already
                      in the public domain;

                  (b) information which, after disclosure, becomes a part of the
                      public domain by publication through no violation of this
                      Agreement;

                  (c) information which the Recipient is able to prove by
                      competent written evidence to have been in possession of
                      prior to any disclosure;

                  (d) information which is hereafter lawfully disclosed to the
                      Recipient by a third party, which third party did not
                      acquire the information under a still effective obligation
                      of confidentiality to the disclosing Party;


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                  (e) information the Recipient is able to prove by competent
                      written evidence to have been is independently developed
                      by or for the Recipient without use of the confidential
                      information of the disclosing Party; and

                  (f) information disclosed upon approval of the disclosing
                      Party.

11.2     Authorized Disclosures. Confidential information of the disclosing
         Party may be disclosed to employees, agents, consultants or
         sublicensees of the Recipient or its Affiliates, but only to the extent
         required to accomplish the purposes of this Agreement and only if the
         Recipient's and its Affiliates' employees, agents, consultants and
         sublicensees to whom disclosure is to be made are bound by
         confidentiality obligations at least as stringent as those herein.
         Notwithstanding any other provision of this Agreement, disclosure of
         confidential information shall not be precluded if such disclosure: (a)
         is in response to a valid order of a court or other governmental body
         of the United States or any political subdivision thereof; or (b) is
         required by law or regulation; provided, however, that the Recipient
         shall first have given reasonable prior notice to the disclosing Party
         and shall have made a reasonable effort to obtain a protective order,
         or to cooperate with the disclosing Party's efforts, as applicable, to
         obtain a protective order limiting the extent of such disclosure and
         requiring that the confidential information so disclosed be used only
         for the purposes for which such order was issued or as required by such
         law or regulation. The Parties will consult with each other on the
         provisions of this Agreement to be redacted in any filings made by the
         parties with the Securities and Exchange Commission or as otherwise
         required by law.

11.3     Press Release. Neither Party shall issue any press release or other
         public statement concerning the existence or terms of this Agreement or
         any activities related hereto without consulting and agreeing with the
         other Party. However, each Party may disclose the existence of this
         Agreement without the other Party's approval if such approval has been
         requested but not received within forty-eight (48) hours and such party
         concludes, after consulting with its legal advisors, that it is
         required by law or regulatory or listing agency to disclose the
         transaction or part thereof. In addition, following the initial joint
         press release announcing this Agreement, either Party shall be free to
         disclose, without the other Party's prior written consent, the
         existence of this Agreement, the identity of the other Party and those
         terms of the Agreement which have already been publicly disclosed in
         accordance herewith.

                                   ARTICLE XII
                                 INDEMNIFICATION

12.1     By EPMN. EPMN shall defend, indemnify and hold GCOR and its Affiliates
         and their respective officers, directors, employees, agents or
         representatives (the


                                      22.
<PAGE>
         "GCOR Indemnitees") harmless against any liability, damage, loss, cost
         or expense, including legal fees (collectively, "Liability"), incurred
         by any GCOR Indemnitee arising out of our resulting from: (i) EPMN's
         breach of a material term of this Agreement, including any material
         breach of any representation or warranty of EPMN set forth in Section
         7.1; and (ii) any third party claims or suits made or brought against
         any GCOR Indemnitee to the extent such Liability arises out of or
         relates to EPMN's research and development of the Licensed Product or
         EPMN's use of the EPMN Technology or the Collaboration Patent Rights,
         except to the extent such Liability results from the negligence or
         willful misconduct of GCOR.

12.2     By GCOR. GCOR shall defend, indemnify and hold EPMN and its Affiliates
         and their respective officers, directors, employees, agents or
         representatives (the "EPMN Indemnitees") harmless against any Liability
         incurred by any EPMN Indemnitee arising out of or resulting from: (i)
         GCOR's breach of a material term of this Agreement, including any
         material breach of a representation or warranty of GCOR set forth in
         Section 7.2; and (ii) any third party claims or suits made or brought
         against any EPMN Indemnitee to the extent such Liability arises out of
         or relates to GCOR's research, development, manufacture, use or sale of
         the Licensed Product or GCOR's use of the EPMN Technology or
         Collaboration Patent Rights, except to the extent such Liability
         results from the negligence or willful misconduct of EPMN.

12.3     Notice and Cooperation. If either Party hereunder receives notice of
         any claim or of the commencement of any action, administrative or legal
         proceeding, or investigation as to which the indemnity provided for in
         Section 12.1 or 12.2 hereof may apply:

         12.3.1 The party seeking indemnification shall notify the indemnifying
         party of such fact within fourteen (14) days at the address noted in
         Section 13.7; provided that the failure to so notify shall not release
         an indemnifying party of its obligation hereunder unless such failure
         shall be materially detrimental to the defense of any such action,
         proceeding or investigation; and

         12.3.2 The party seeking indemnification shall cooperate with and
         assist the indemnifying party and its representatives in the
         investigation and defense of any claim and/or suit for which
         indemnification is provided.

12.4     Defense and Settlement. The indemnifying party shall control the
         defense of any claim and/or suit for which indemnification is provided
         under this Article XII. This agreement of indemnity shall not be valid
         as to any settlement of a claim or suit or offer of settlement or
         compromise without the prior written approval of the indemnifying
         party.

12.5     Limitation of Liability. EXCEPT FOR AMOUNTS PAYABLE UNDER ARTICLES III,
         V and VIII AND LIABILITY FOR BREACH OF ARTICLE XI,


                                      23.
<PAGE>
         NEITHER PARTY SHALL BE ENTITLED TO RECOVER FROM THE OTHER PARTY ANY
         SPECIAL, INCIDENTAL, CONSEQUENTIAL OR PUNITIVE DAMAGES IN CONNECTION
         WITH THIS AGREEMENT OR ANY LICENSE GRANTED HEREUNDER.

                                  ARTICLE XIII
                                  MISCELLANEOUS

13.1     Force Majeure. Each of the Parties hereto shall be excused from the
         performance of its obligations hereunder (other than payment
         obligations) and shall not be liable for damages to the other in the
         event that such performance is prevented by circumstances beyond its
         effective control. Such excuse from performance shall continue for as
         long as the condition responsible for such excuse continues and for a
         period of thirty (30) days thereafter, provided that if such excuse
         continues for a period of one hundred and eighty (180) days, the Party
         whose performance is not being prevented shall be entitled to terminate
         this Agreement. For the purpose of this Agreement circumstances beyond
         the effective control of the Party which excuse said Party from
         performance shall include, without limitation, acts of God, enactments,
         regulations or laws of any government, injunctions or judgment of any
         court, war, civil commotion, destruction of facility or materials by
         fire, earthquake, storm or other casualty, plague of epic proportions,
         famine, labor disturbances and failure of public utilities or common
         carrier.

13.2     Independent Contractors. Nothing in this Agreement is intended or shall
         be deemed to constitute a partnership, agency, employment or joint
         venture relationship between the Parties. All activities by the Parties
         hereunder shall be performed by the Parties as independent parties.
         Neither Party shall incur any debts or make any commitment for or on
         behalf of the other Party except to the extent, if at all, specifically
         provided herein or subsequently agreed upon.

13.3     Assignment. This Agreement shall not be assignable by either Party
         without the prior written consent of the other Party, such consent not
         to be unreasonably withheld or delayed, except a Party may make such an
         assignment without the other Party's consent to Affiliates or to a
         successor to substantially all of the business assets relating to the
         Licensed Field of such Party, whether by merger, sale of stock, sale or
         transfer of assets or other transaction; provided, however, that in the
         event of such transaction, no intellectual property rights of any
         Affiliate or third party that is an acquiring party shall be included
         in the technology licensed hereunder. This Agreement shall be binding
         upon and inure to the benefit of the Parties' successors, legal
         representatives and assigns.

13.4     Amendments of Agreement. This Agreement may be amended or modified or
         one or more provisions hereof waived only by a written instrument
         signed by both Parties.


                                      24.
<PAGE>
13.5     Severability. In the event that any one or more of the provisions of
         this Agreement should for any reason be held by any court or authority
         having jurisdiction over this Agreement and the Parties to be invalid,
         illegal or unenforceable, such provisions shall be deleted in such
         jurisdiction; elsewhere this Agreement shall not be affected.

13.6     Article Headings. The section headings contained in this Agreement are
         for convenience only and are to be of no force or effect in construing
         and interpreting this Agreement.

13.7     Notices. Any notice, report, request, approval, payment, consent or
         other communication required or permitted to be given under this
         Agreement shall be in writing and shall for all purposes be deemed to
         be fully given and received, if delivered in person or sent by
         registered mail, postage prepaid or by facsimile transmission to the
         respective parties at the following addresses:

                  If to EPMN:        EPIMMUNE INC.
                                     5820 Nancy Ridge Drive
                                     San Diego, CA  92121
                                     Attention:  Chief Executive Officer
                                     Fax No.:  858-860-2600

                  If to GCOR:        GENENCOR INTERNATIONAL, INC.
                                     925 Page Mill Road
                                     Palo Alto, CA  94304
                                     Attention:  General Counsel
                                     Fax No.:  650-845-6507

         Either party may change its address for the purpose of this Agreement
         by giving the other Party written notice of its new address.

13.8     Non-Waiver For Failure To Enforce Compliance. The express or implied
         waiver by either Party of a breach of any provision of this Agreement
         shall not constitute a continuing waiver of other breaches of the same
         or other provisions of this Agreement.

13.9     Applicable Law. This Agreement shall be construed and interpreted in
         accordance with the laws of the State of California without regard to
         conflict of law provisions.

13.10    Counterparts. This Agreement may be executed in one or more
         counterparts, each of which is an original but all of which, taken
         together, shall constitute one and the same instrument.


                                      25.
<PAGE>
         IN WITNESS WHEREOF, this License Agreement has been entered into on the
Effective Date signed by the Parties.

                                    GENENCOR INTERNATIONAL, INC.
                                    By: /s/ Debby Jo Blank
                                       -----------------------------------
                                    Name:   Debby Jo Blank
                                         ---------------------------------
                                    Title:   CBO
                                          --------------------------------

                                    EPIMMUNE INC.

                                    By: /s/ Robert J. De Vaere
                                       -----------------------------------
                                            Robert J. De Vaere
                                            Vice President Finance, and
                                            Chief Financial Officer


                       SIGNATURE PAGE TO LICENSE AGREEMENT
<PAGE>
                                   APPENDIX A
                          COMBINATION PRODUCT EXAMPLES

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                                               *CONFIDENTIAL TREATMENT REQUESTED
<PAGE>
                                   APPENDIX B

                             THIRD PARTY TECHNOLOGY

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                                               *CONFIDENTIAL TREATMENT REQUESTED
<PAGE>
                                   APPENDIX C

                           SAMPLE ROYALTY CALCULATION

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                                               *CONFIDENTIAL TREATMENT REQUESTED