XENOVA LIMITED AND

* CONFIDENTIAL INFORMATION HAS BEEN OMITTED AND FILED SEPARATELY WITH THE
SECURITIES AND EXCHANGE COMMISSION. REDACTED PORTIONS OF THIS EXHIBIT ARE MARKED
BY AN [_].

                                                                    Confidential


                                 XENOVA LIMITED



                                       AND



                           OXXON THERAPEUTICS LIMITED




                     ---------------------------------------

                        DEVELOPMENT AND LICENCE AGREEMENT

                     ---------------------------------------







                               Xxxxxxxx & Company
                               00 Xxxxxxxxxxx Xxxx
                                  Xxxxxxxxxxxx
                                  Xxxx XX00 0XX
                           xxxx.xxxxxxxxxxxxxxxxxx.xxx
                           ---------------------------





                                                                    Confidential

                        DEVELOPMENT AND LICENCE AGREEMENT


THIS AGREEMENT dated 12th January 2005 is made between:

(1)    XENOVA LIMITED (company registration number 01970244) ("Xenova") a
       company incorporated in England and Wales whose registered office is at
       000 Xxxxxxxxxx Xxxxxx, Xxxxxx, Xxxxxxxxx XX0 0XX; and

(2)    OXXON THERAPEUTICS LIMITED (company registration number 03671700)
       ("Oxxon") a company incorporated in England and Wales whose principal
       place of business is at Xxxxxx House, 3 Xxxxxx Xxxxxxxx Avenue, The
       Oxford Science Park, Oxford OX4 4GP.

RECITALS:

A.     Xenova is the beneficial owner of certain Xenova Patent Rights, and
       possesses certain Xenova Know-how and Xenova Materials relating to the
       DISC-HSV Vector.

B.     Oxxon has expertise in developing immunotherapeutic products based on a
       proprietary Heterologous PrimeBoost approach. Oxxon also has expertise in
       developing viral based antigen delivery vectors for the treatment of
       cancer and infectious disease.

C.     Oxxon wishes to pursue the further development and commercialisation of
       the DISC-HSV Vector in Selected Indications and Fields, in accordance
       with the provisions of this Agreement.

D.     Xenova is willing to grant to Oxxon, and Oxxon is willing to accept, a
       licence in the Selected Indications in the Field under the Xenova Patent
       Rights and to use the Xenova Know-how and Xenova Materials, all in
       accordance with the provisions of this Agreement.


IT IS AGREED AS FOLLOWS:

1      DEFINITIONS

In this Agreement, the following words shall have the following meanings:

AFFILIATE                  In relation to a Party, means any entity or person
                           that Controls, is Controlled by, or is under common
                           Control with that Party.

ARISING INTELLECTUAL       Any and all of the Arising Patents, Arising Know-how
PROPERTY                   and Arising Materials.

ARISING KNOW-HOW           Technical, commercial and all other information
                           generated by Oxxon during the continuation of this
                           Agreement that relates to any of the Xenova
                           Intellectual Property or any Licensed Product(s),
                           including any scientific or regulatory data, product
                           licence applications and approvals, clinical trial
                           licence applications and approvals, and development
                           and marketing plans and activities.

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ARISING MATERIALS          Any and all materials that may be generated or
                           developed by Oxxon in the course of this Agreement,
                           including any materials based on or derived from any
                           Xenova Materials.

ARISING PATENTS            Any and all patents and patent applications that may
                           be applied for or obtained in respect of any
                           invention(s) made by Oxxon during the continuation
                           of this Agreement and which relate to any Xenova
                           Intellectual Property, together with any
                           continuations, continuations in part, extensions,
                           reissues, divisions, and any patents, supplementary
                           protection certificates and similar rights that are
                           based on or derive priority from the foregoing.

BLA                        A biologies license application (as that term is
                           used in Title 21 of the United States Code of Federal
                           Regulations) filed with the FDA seeking regulatory
                           approval to market and sell any Licensed Product in
                           the United States for a particular indication or the
                           non-U.S. equivalent thereof.

COMMENCEMENT DATE          The date of execution of this Agreement by the
                           Parties.

CONTROL                    Direct or indirect beneficial ownership of 50% (or,
                           outside a Party's home territory, such lesser
                           percentage as is the maximum permitted level of
                           foreign investment) or more of the share capital,
                           stock or other participating interest carrying the
                           right to vote or to distribution of profits of that
                           entity or person, as the case may be.


DEVELOPMENT AND            The development and commercialisation plan for
COMMERCIALISATION PLAN     Licensed Product(s), the initial programme for which
                           is briefly summarised in Schedule 3, to be further
                           defined in accordance with Clause 3.1 and as may be
                           amended from time to time by Oxxon.


DEVELOPMENT AND            The report described in Clause 3.4 as amended from
COMMERCIALISATION REPORT   time to time.

DISC-GMCSF                 A recombinant virus that has been developed by
                           Xenova and is designated dH2T, and which is a
                           disabled infectious single cycle herpes simplex type
                           2 virus that expresses the cytokine human
                           granulocyte macrophage colony stimulating factor
                           from the gH locus from which the gH gene has been
                           deleted.

DISC-HSV VECTOR            A disabled infectious single cycle herpes simplex
                           virus from which the gH gene has been deleted and/or
                           from which another gene that is essential for virus
                           replication may be deleted, and into which a
                           different gene(s) is or will be substituted, as a
                           result of which substitution the virus expresses
                           heterologous gene(s). The foregoing definition shall
                           include DISC-GMCSF which has been genetically
                           modified.

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                           For the avoidance of doubt, a DISC-HSV vector that
                           is "empty" (including but not limited to the vector
                           known as dH2A), that is to say it does not express
                           any heterologous gene(s) as described in the
                           previous sentence of this definition, is excluded
                           from the definition of DISC-HSV Vector for the
                           purposes of this Agreement.


[_] YEAR PERIOD            The period commencing on the Commencement Date and
                           ending on the earlier of (a) the [_] anniversary
                           of the Commencement Date; and (b) any termination of
                           this Agreement.


FDA                        The United States Food and Drug Administration and
                           any successor agency or authority thereto.

FIELD                      Field A and Field B.

FIELD A                    The use of DISC-HSV Vector in Heterologous
                           PrimeBoost regimes (where the DISC-HSV Vector is
                           either the [_] or [_]) for prophylactic  and
                           therapeutic applications for the Indications.

                           For the avoidance of doubt, for the purposes of this
                           Agreement, Field A shall not include the use of
                           DISC-HSV Vector in the prophylactic setting for the
                           prevention of herpes virus infection/disease.

FIELD A INDICATIONS        Those Indications that Oxxon selects for use in
                           Field A in accordance with the provisions of
                           Clause 4.3.

FIELD B                    The use of DISC-HSV Vector or DISC-GMCSF as a
                           [_] for prophylactic and therapeutic
                           applications for the Indications.

                           For the avoidance of doubt, for the purposes of this
                           Agreement, Field B shall not include the use of
                           DISC-HSV Vector in the prophylactic setting for the
                           prevention of herpes virus infection/disease.

FIELD 8 INDICATIONS        Those Indications that Oxxon selects for use in
                           Field B in accordance with the provisions of
                           Clause 4.3.

FURTHER INDICATIONS        Those additional indications other than the
                           Indications and the Haematology Indications, as
                           defined in this Agreement that Oxxon selects in
                           accordance with Clause 4.3(d)(ii).

HAEMATOLOGY INDICATIONS    The application of Licensed Product to transduce
                           cells selected from the group consisting of
                           haematopoietic cells, malignant cells of the
                           haematopoietic lineage, and malignant or
                           non-malignant CD34+ cells.

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HETEROLOGOUS               A multi-stage heterologous regimen involving the
PRIMEBOOST                 sequential delivery of an antigen to both prime and
                           boost an immune response. The antigen used in the
                           prime and boost may or may not be identical. For the
                           avoidance of doubt, the prime and/or boost may be
                           undertaken one or more times.

IND                        An Investigational New Drug Application filed or to
                           be filed with the FDA with regard to a Licensed
                           Product prior to beginning clinical trials of any
                           Licensed Product or the non-U.S. equivalent thereof.

INDICATIONS                [_]

INITIAL INDICATIONS        Those Field A Indications and/or Field B Indications
                           that Oxxon selects in accordance with Clauses 4.3(b)
                           and (c).

JOINT DEVELOPMENT          A committee to be established, and operating, in
FORUM                      accordance with the provisions of Clause 2.

KNOW-HOW                   The Xenova Know-how and the Arising Know-how.

LICENSED PRODUCT(S)        Any and all products that incorporate DISC-GMCSF or
                           DISC-HSV Vector and that are manufactured, sold or
                           otherwise supplied by Oxxon or Sub-licensees and
                           which (a) are within any Valid Claim of the Xenova
                           Patent Rights; and/or (b) incorporate, or their
                           development makes use of, any of the Xenova Know-how
                           or the Xenova Materials. References in this
                           Agreement to different Licensed Products (e.g., the
                           first and second Licensed Products) shall be
                           understood as referring to Licensed Products that
                           require, or will require, separate Marketing
                           Authorisations in the United States of America.

MARKETING AUTHORISATION    Regulatory approval to market and sell a Licensed
                           Product in any part of the Territory and shall
                           include, without limitation, approval granted with
                           respect to any BLA, NDA or the non-US equivalent
                           thereof.

NDA                        A new drug application (as that term is used in
                           Title 21 of the United States Code of Federal
                           Regulations) filed with the FDA seeking Regulatory
                           Approval to market and sell any Licensed Product(s)
                           in the United States for a particular indication or
                           the non-U.S. equivalent thereof.

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NET SALES VALUE            The invoiced price of Licensed Product(s) sold by
                           Oxxon or any of its Affiliates (or, in the context
                           of Clause 6.6(b) its Sublicensees, or in the context
                           of Clause 6.7 and 6.11 Oxxon or any of its Affiliates
                           and/or its Sublicensees) to independent third
                           parties in arm's length transactions exclusively for
                           money or, where the sale is not at arm's length, the
                           price that would have been so invoiced if it had
                           been at arm's length, after deduction of normal trade
                           discounts actually granted and any credits actually
                           given, and, provided the amounts are separately
                           charged on the relevant invoice, any costs of
                           packaging, insurance, carriage and freight, any
                           value added tax or other sales tax, and any import
                           duties or similar applicable government levies.

OPT-IN FEES                The fees described in Clause 6.4.

PARTIES                    Xenova and Oxxon, and "Party" shall mean either of
                           them.

PATENTS                    Any and all of the Xenova Patent Rights and the
                           Arising Patents.

PHASE I STUDIES            As to a specific Licensed Product, one or more
                           controlled and lawful studies in humans, the
                           principal purpose of which is a preliminary
                           determination of safety of the Licensed Product for
                           its intended use in healthy individuals or patients
                           to support its continued testing in similar clinical
                           trials prescribed by the FDA or any relevant foreign
                           regulatory authority.

PHASE II STUDIES           As to a specific Licensed Product, one or more
                           controlled and lawful studies in humans of the
                           safety, dose ranging and efficacy of such Licensed
                           Product, which is prospectively designed to generate
                           sufficient data (if successful) to commence Phase III
                           Studies of such product.

PHASE III STUDIES          As to a specific Licensed Product, one or more
                           controlled and lawful studies in humans of the
                           efficacy and safety of such Licensed Product, which
                           is prospectively designed to demonstrate
                           statistically whether such Licensed Product is
                           effective and safe for use in a particular indication
                           in a manner sufficient to file a BLA or NDA to
                           obtain regulatory approval to market and sell that
                           Licensed Product in any part of the Territory for
                           the indication being investigated by the study.

PRE-CLINICAL STUDIES       As to a specific Licensed Product, in vitro or in
                           vivo (non-human) studies, including but not limited
                           to evaluation of the safety, immunogenicity,
                           pharmacology or toxicity profile of a therapeutic
                           agent.

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REASONABLE AND DILIGENT    Exerting such efforts and employing such resources as
EFFORTS                    would normally be exerted or employed by a
                           reasonable, [_] when utilizing sound and  reasonable
                           scientific, business and medical practice and
                           judgment in order to develop the product in a timely
                           manner and maximise the economic return to the
                           Parties from its commercialisation.


REVOCATION PROCEEDINGS     Any proceedings before a national or international
                           Patent Office where the validity of any of the
                           Xenova Patent Rights is at issue including opposition
                           proceedings in respect of European patents and
                           interference proceedings in respect of US patents,
                           but excluding any proceedings that form part of, or
                           are linked with, proceedings in which allegations of
                           patent infringement are made.

ROYALTY RECEIPTS           The amount of any royalties received by, or due to,
                           Oxxon or any of its Affiliates calculated on the
                           sale of Licensed Product(s) less any Value Added
                           Tax.

SELECTED INDICATIONS       The Field A Indications (if any) and the Field B
                           Indications (if any).

SUB-LICENSEE               Any third party (including an Affiliate of Oxxon) to
                           whom Oxxon has sub-licensed any of Oxxon's rights
                           under this Agreement.

TERRITORY                  The World.

UPFRONT RECEIPTS           Subject to Clause 6.6(a)(iii) and (iv), the amount of
                           any payment (excluding Value Added Tax), and the
                           value of any non-monetary receipt, obtained by, or
                           due to, Oxxon or its Affiliate, by way of "upfront"
                           or initial consideration (whether payable in one or
                           more instalments) in relation to the sub-licensing
                           (including the grant of any option over a
                           sub-licence) of any Xenova Intellectual Property,
                           and including any of the following:

                           (a)  up-front payments due under any sub-licence
                                agreement;

                           (b)  payments in excess of a fair market rate for
                                the funding of research or development
                                activities related to any Licensed Product;

                           (c)  where any sub-licence is to be granted under
                                cross- licensing arrangements, the value of any
                                third party licence obtained under such
                                arrangements;

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                           (d)  any premium paid over the fair market value of
                                shares, options or other securities in respect
                                of any of the share capital of Oxxon or its
                                Affiliate (such fair market value to be
                                determined on the assumption that Xenova had not
                                granted, nor agreed to grant, any rights to
                                Oxxon in respect of any Xenova Intellectual
                                Property);

                           (e)  any loan, guarantee or other financial benefit
                                made or given other than on normal market
                                terms; and

                           (f)  any shares, options or other securities obtained
                                from a third party.

VALID CLAIM                A claim of a patent or patent application that has
                           not expired or been held invalid or unenforceable by
                           a court of competent jurisdiction in a final and
                           non-appealable judgment.

XENOVA INTELLECTUAL        Any and all of the Xenova Patent Rights, Xenova
PROPERTY                   Know-how and Xenova Materials.

XENOVA KNOW-HOW            Technical information in the possession of Xenova or
                           its Affiliates in the Field relating to (a) DISC-HSV
                           Vector and/or (b) the inventions claimed in the
                           Xenova Patent Rights, and being further described in
                           the attached Schedule 2.

XENOVA MATERIALS           Physical materials in the possession of Xenova or its
                           Affiliates in the Field relating to (a) DISC-HSV
                           Vector and/or (b) the inventions claimed in the
                           Xenova Patent Rights, being those described in the
                           attached Schedule 2 and such other materials in the
                           possession of Xenova or its Affiliates that:

                           (a)  were developed by Xenova or its Affiliates in
                                its research and development programme for
                                DISC-HSV prior to the Commencement Date; and

                           (b)  fall within the categories set out in Schedule
                                2; and

                           (c)  Oxxon may reasonably request for the development
                                of Licensed Product(s); and

                           (d)  of which Xenova or its Affiliates is the
                                beneficial owner; and

                           (e)  which Xenova or its Affiliates is not prevented
                                from providing as a result of a pre-existing
                                agreement with a third party.


XENOVA PATENT RIGHTS       The patents and patent applications described in the
                           attached Schedule 1 together with any continuations,
                           continuations in part, extensions, reissues,
                           divisions, and any patents, supplementary protection
                           certificates and similar rights that are based on or
                           derive priority from the foregoing.


XENOVA REPRESENTATIVES     Xx Xxxxx Xxxxxxxxxx and Xx Xxxxxxxxx Xxxxxxxxx and
                           the executive board directors of Xenova.

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2      JOINT DEVELOPMENT FORUM

2.1    Formation, Within 90 days after the Commencement Date, the Parties shall
       establish a Joint Development Forum, by each Party designating its
       initial members to serve on the Joint Development Forum and notifying the
       other Party of its dates of availability for the first meeting of the
       Joint Development Forum. At the Joint Development Forum Oxxon shall
       report to Xenova on its progress in developing Licensed Product(s) for
       purposes of commercialization in the Field in the Territory. The Joint
       Development Forum shall consist of up to three (3) representatives
       designated by each Party. Each Oxxon representative shall have relevant
       and appropriate development expertise in order to report on and discuss
       the development of the Licensed Product(s). If a representative of a
       Party is unable to attend a meeting of the Joint Development Forum, such
       Party may designate an alternate to attend such meeting. In addition,
       each Party may, at its discretion, invite a reasonable number of other
       employees, consultants or scientific advisors to attend the meetings of
       the Joint Development Forum, provided that such invitees are bound by
       appropriate confidentiality obligations. Each Party may change one or all
       of its representatives to each Joint Development Forum at any time upon
       notice to the other Party.

2.2    Meetings, The Joint Development Forum shall meet every six months and at
       such other times as the Parties may agree. The first meeting of the Joint
       Development Forum shall be held as soon as reasonably practicable, but in
       no event later than 90 days after the Commencement Date. Meetings shall
       be held at such place or places as are mutually agreed or by
       teleconference or videoconference; provided, however, that there shall be
       at least one face-to-face meeting per calendar year.

2.3    Responsibilities. During the continuation of this Agreement, the Joint
       Development Forum shall:

       (a)    receive reports from Oxxon on the progress of the development of
              Licensed Products;

       (b)    provide Xenova with an opportunity to comment on the Development
              and Commercialisation Plan;

       (c)    enable Xenova to provide information to Oxxon that it has in its
              possession or control which may facilitate Oxxon's development of
              Licensed Products; and

       (d)    facilitate the initial transfer of Xenova Know-How between the
              Parties for purposes of enabling Oxxon to develop Licensed
              Products;

       For the avoidance of doubt the Joint Development Forum shall not have any
       role or responsibility in relation to determining whether Oxxon has
       complied or will comply with its obligations to Xenova under Clauses 3 or
       7.1.

2.4    Disputes. If agreement cannot be reached within the Joint Development
       Forum, Oxxon shall have the right to make the final determination
       concerning the resolution of the disagreement.

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3      DEVELOPMENT

3.1    Development and Commercialisation Plan; IND filing. Without prejudice to
       the generality of Oxxon's obligations under Clause 7.1, Oxxon shall:

       (a)    Within [_] of Oxxon making its selection of its first Indication
              pursuant to Clause 4.3(b) Oxxon shall create a Development and
              Commercialisation Plan based on the initial, summary Development
              and Commercialisation Plan set out in Schedule 3, which will set
              out Oxxon's proposed development of Licensed Product(s) in
              relation to such first Indication. The Development and
              Commercialisation Plan shall describe in outline Oxxon's
              development activities for the applicable Licensed Product in the
              applicable Indication. Oxxon will update the Development and
              Commercialisation Plan on a regular (and at least six-monthly)
              basis, and such updates shall address the relevant stage of
              development and commercialization of the Licensed Product(s)
              including information under the headings set out in Part 2 of
              Schedule 3 as and when such information is available; and

       (b)    Oxxon shall use Reasonable and Diligent Efforts to file, within
              [_] of selecting each Indication in accordance with Clause 4.3, an
              IND for a Licensed Product for such Indication. In the event that
              Oxxon is in breach of its obligation to use Reasonable and
              Diligent Efforts to file in accordance with this Clause 3.1(b)
              then Xenova shall only be entitled to exercise any right of
              termination under Clause 10.2.2 if Oxxon is in breach of its
              obligation in respect of all Selected Indications.

3.2    Development activities. With respect to each Licensed Product, Oxxon
       shall be responsible for the development and commercialisation of such
       Licensed Product in the Field in the Territory in accordance with the
       Development and Commercialisation Plan. Such development and
       commercialisation shall be carried out in accordance with the provisions
       of this Agreement.

3.3    Development costs. Oxxon shall bear all costs associated with the
       development of Licensed Product(s), including costs incurred in
       connection with the Development and Commercialisation Plan save that
       Xenova shall bear its own costs associated with attending and
       participating in the Joint Development Forum as set out in Clauses 2.1 to
       2.4 . If Xenova agrees with Oxxon to conduct work as part of the
       Development and Commercialisation Plan, Xenova's costs of conducting such
       work shall be borne by Oxxon, with the time costs of Xenova
       representatives being charged to Oxxon on a full-time equivalent (FTE)
       basis. Xenova's FTE rate for its representatives shall be agreed between
       the Parties but in any event it shall be not less than [_] per annum (on
       a pro-rata basis) plus all product-related consumable costs and external
       costs associated with such work. For the avoidance of doubt, these rates
       shall not apply to any manufacturing work performed by Xenova, which
       would be the subject of separate manufacturing agreement(s) as may be
       agreed in writing by the Parties.

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3.4    Reporting. Without prejudice to the generality of Oxxon' s obligations
       under Clause 7.1, Oxxon shall provide a Development and Commercialisation
       Report to Xenova at least twice per year to Xenova (and in any event
       prior to each meeting of the Joint Development Forum), summarising its
       past, current and projected activities taken or to be taken by Oxxon to
       bring Licensed Product(s) to market and maximise the sale of Licensed
       Product(s) worldwide; and from time to time at Xenova's reasonable
       request and on reasonable notice Oxxon shall provide details of such
       activities. Xenova's receipt or approval of any such report shall not be
       taken to waive or qualify Oxxon's obligations under Clause 7.1.

4.     GRANT OF RIGHTS

4.1    Licences to Xenova Intellectual Property. Xenova hereby grants to Oxxon,
       subject to the provisions of this Agreement, the following licences in
       the Field:

       (a)    an exclusive licence under the Xenova Patent Rights, with the
              right to sub-license, subject to Clause 4.6, to develop,
              manufacture, have manufactured, use and sell product(s) in the
              Field in the Territory for the Selected Indications; and

       (b)    an exclusive licence to use the Xenova Know-how and the Xenova
              Materials, with the right to sub-license, subject to Clause 4.6,
              to develop, manufacture, have manufactured, use and sell
              product(s) in the Field in the Territory for the Selected
              Indications.

       For the avoidance of doubt, Oxxon shall only be entitled to exploit the
       rights granted to Oxxon under the licences set out in Clauses 4.1 (a) and
       4.1(b) in respect of the Field A Indications in Field A, and in respect
       of the Field B Indications in Field B.

4.2    [_]

4.3    Selection of Indications. The licences granted under Clause 4.1 are
       limited to the Indications that Oxxon selects in accordance with the
       provisions of this Clause 4.3, as follows:

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       (a)    Oxxon shall have the exclusive right to select one or more of the
              Indications, in Field A and/or in Field B, subject to the
              provisions of the following paragraphs of this Clause 4.3. In
              respect of each Indication, Oxxon shall exercise this right from
              time to time by giving written notice to Xenova, within the
              relevant time-limit referred to in this Clause, stating the
              Indication and whether it is selected for Field A or Field B.

       (b)    Within [_] of the Commencement Date, Oxxon will select [_]
              Indications in Field A.


       (c)    Within [_] of the Commencement Date, Oxxon will select [_]
              Indications in Field B.

       (d)    Provided that Oxxon has selected [_] Indications in Field A and
              [_] Indications in Field B in accordance with the time limits
              stated in paragraphs (b) and (c) above:

              (i)    during the [_], Oxxon may select [_] further Indications in
                     Field A and/or in Field B, subject to payment of the Opt-in
                     Fees in respect of each Indication that is selected in
                     either of Field A or Field B.

              (ii)   Provided that Oxxon has [_] develop such Further
                     Indications in accordance with this Agreement, during the
                     [_] Oxxon may notify Xenova of Further Indications in Field
                     A and/or in Field B that it wishes to select.

              (iii)  On receipt of a valid notice pursuant to Clause 4.3(d)(ii)
                     Oxxon shall, subject to Clause 4.3(d)(iv) be entitled to a
                     licence to such Further Indication in accordance with
                     Clause 4.1.

              (iv)   In the event that Xenova has granted prior rights to any
                     third party and as a result is not able to grant a licence
                     to Oxxon in accordance with Clause 4.3(d)(iii) or such
                     grant would result in Xenova being in breach of its
                     obligations under any agreement with a third party, Xenova
                     shall offer to Oxxon a licence to the Further Indication to
                     the extent available. Such licence shall, to the extent
                     possible, reflect the terms of the licence granted to Oxxon
                     under Clause 4.1 and the other provisions of this Agreement
                     (including its financial provisions) save that, if the
                     rights granted are less than those provided for under
                     Clause 4.1, the Parties will negotiate in good faith to
                     agree the appropriate royalty rate payable in respect of
                     such licence and for the avoidance of doubt no such licence
                     shall be granted until all of the terms of the licence
                     agreement have been agreed in writing.

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              (v)    Oxxon's right of selection under this paragraph (d) shall
                     continue during the [_], except that this right shall [_]
                     of the Commencement Date if Oxxon [_], on or before the due
                     date, the annual fee that is due on that [_] under Clause
                     6.4(a) ("Payment Default"). Except where Oxxon's rights
                     have expired due to [_], Oxxon may extend its right of
                     selection under Clause 4.3(d)(ii) beyond the [_] for
                     successive periods of [_] by [_] on or before the [_] of
                     the Commencement Date and on [_] of the Commencement Date
                     the annual fee due under Clause 6.4(b).

4.4    Arising Intellectual Property.

4.4.1  Oxxon shall own all Arising Intellectual Property.

4.4.2  Oxxon agrees to grant to Xenova an exclusive, worldwide licence under
       Arising Intellectual Property outside the Field on reasonable commercial
       terms, to research, develop, make, have made, import, use, sell and
       otherwise deal in any and all products and processes outside the Field.
       If the Parties are unable to agree such terms within 90 days of either
       Party requesting the negotiation of such terms ("Exclusivity Period")
       then Oxxon shall not be obliged to grant a licence to Xenova and shall be
       free to discuss and conclude with third parties licensing agreements
       relating to the Arising Intellectual Property.

4.5    Formal licences. If requested by Oxxon, and at Oxxon's administrative
       cost, the Parties shall execute such formal licences as may be necessary
       or appropriate for registration with Patent Offices and other relevant
       authorities in particular territories. In the event of any conflict in
       meaning between any such licence and the provisions of this Agreement,
       the provisions of this Agreement shall prevail. The Parties shall use
       reasonable endeavours to ensure that, to the extent permitted by relevant
       authorities, this Agreement shall not form part of any public record.

4.6    Sub-licensing. Oxxon shall be entitled to grant sub-licences (which for
       the purposes of this Clause 4.6 shall include any option or right to
       acquire a sub-licence) of its rights under this Agreement to any person
       (including without limitation any Affiliate of Oxxon), provided that:

       (a)    Oxxon enters into a written agreement with each Sub-licensee;

       (b)    the sub-licence shall impose appropriate obligations on the
              Sub-licensee which are equivalent to the obligations on Oxxon
              under Clauses 3.4,4.4, 5.5 to 5.8, 6.12, 7 and 10 of this
              Agreement; and

                                       13





                                                                    Confidential

       (c)    [_]

       (d)    within [_] following the grant of any sub-licence Oxxon shall
              notify Xenova that a sub-licence has been entered into and provide
              a true copy of the sub-licence agreement to Xenova; and

       (e)    for as long as Oxxon remains a party to the sub-licence agreement,
              Oxxon shall be [_] of the sub-licence agreement by the
              sub-licensee, as if [_] had been that of Oxxon under this
              Agreement.

4.7    No other licence. It is acknowledged and agreed that except for the
       licence(s) expressly granted by the provisions of this Clause 4, Xenova
       reserves all its rights. Without prejudice to the generality of the
       foregoing Xenova reserves all rights under the Xenova Intellectual
       Property outside the Field. It is understood and agreed that under
       regulatory GCP Xenova will be required to retain archive samples of
       Xenova Materials and archive originals or copies of Xenova Know-how. For
       the avoidance of doubt, no rights are granted under this Agreement in the
       Haematology Indications.

4.8    Quality. Oxxon shall be responsible for ensuring that all Licensed
       Product(s) marketed by it or its Sub-licensees are of satisfactory
       quality and comply with all applicable laws and regulations in each part
       of the Territory. Oxxon's liability in respect of such responsibilities
       shall be in accordance with the provisions of Clause 9.2.3.

5.     KNOW-HOW AND CONFIDENTIAL INFORMATION

5.1    Provision of Know-how. Upon Oxxon's reasonable request, Xenova shall free
       of charge supply Oxxon with all Xenova Know-how in existence at the
       Commencement Date that Xenova is at liberty to disclose and that has not
       previously been disclosed to Oxxon and which is reasonably necessary to
       enable Oxxon to undertake the further development of the Licensed
       Product(s). In addition, Xenova shall free of charge supply to Oxxon all
       information which Xenova or its Affiliates receives from any regulatory
       body after the Commencement Date in response to filings made before the
       Commencement Date to the extent that such information relates to the
       Xenova Intellectual Property and would assist Oxxon in the development of
       Licensed Products. The Xenova Know-how shall be subject to the
       confidentiality provisions of Clause 5.6. If Oxxon requires any technical
       support or training to enable it to develop Licensed Products then the
       parties will discuss such requirements and negotiate in good faith to
       agree the terms under which such support or training will be provided.

                                       14





                                                                    Confidential

5.2    Transfer of Materials. Xenova shall supply to Oxxon the Xenova Materials
       in accordance with the provisions of Schedule 2 and in such manner as the
       Parties may agree with a view to ensuring the stability and safe delivery
       of the samples of the Xenova Materials.

5.3    Status of Know-how and Materials. Oxxon acknowledges that the Xenova
       Know-how and Xenova Materials are at an early stage of development.
       Subject to Clause 9, specific results cannot be guaranteed and any
       results, materials, information or other items, including the Xenova
       Know-how and Xenova Materials and inventions claimed in the Xenova Patent
       Rights provided under this Agreement are provided "as is" and without any
       express or implied warranties, representations or undertakings.

5.4    Responsibility for development of Licensed Product(s). Oxxon shall be
       exclusively responsible for the technical and commercial development and
       manufacture of Licensed Product(s) and for incorporating any
       modifications or developments thereto that may be necessary or desirable
       and for all Licensed Product(s) sold or supplied, and accordingly Oxxon
       shall indemnify Xenova in the terms of Clause 9.2.3.

5.5    Use of Know-how. Oxxon undertakes that for a period of [_] from the
       date of first commercial sale of Licensed Product(s) hi the Territory or
       for so long as any substantial part of the Know-how remains subject to
       the obligations of confidence of Clause 5.6, whichever is the shorter, it
       will not use the Xenova Know-how for any purpose except [_].

5.6    Confidentiality obligations. Each Party ("Receiving Party") undertakes:

       (a)    to maintain as secret and confidential all Know-how and other
              technical or commercial information obtained directly or
              indirectly from the other Party ("Disclosing Party") in the course
              of or in anticipation of this Agreement and to respect the
              Disclosing Party's rights therein;

       (b)    to use the same exclusively for the purposes of this Agreement;
              and

       (c)    to disclose the same only to those of its employees, contractors
              and Sub-licensees pursuant to this Agreement (if any) to whom and
              to the extent that such disclosure is reasonably necessary for the
              purposes of this Agreement.

5.7    Exceptions to obligations. The provisions of Clause 5.6 shall not apply
       to Know-how and other information which the Receiving Party can
       demonstrate by reasonable, written evidence;

       (a)    was, prior to its receipt by the Receiving Party from the
              Disclosing Party, in the possession of the Receiving Party and at
              its free disposal; or

       (b)    is subsequently disclosed to the Receiving Party without any
              obligations of confidence by a third party who has not derived it
              directly or indirectly from the Disclosing Party; or

                                       15





                                                                    Confidential

       (c)    is or becomes generally available to the public through no act or
              default of the Receiving Party or its agents, employees,
              Affiliates or sub-licensees; or

       (d)    if the Receiving Party is required to disclose confidential
              information to the courts of any competent jurisdiction, or to any
              government regulatory agency or financial authority, such
              disclosure shall not be a breach of this Clause 5.7, provided that
              the Receiving Party shall:

              (i)    inform the Disclosing Party as soon as is reasonably
                     practicable; and

              (ii)   at the Disclosing Party's request seek to persuade the
                     court, agency or authority to have the information treated
                     in a confidential manner, where this is possible under the
                     court, agency or authority's procedures.

5.8    Disclosure to employees. The Receiving Party shall procure that all of
       its employees, contractors, consultants, advisers and Sub-licensees
       pursuant to this Agreement (if any) who have access to any of the
       Disclosing Party's information to which Clause 5.6 applies, shall be made
       aware of and subject to these obligations and shall have entered into
       written undertakings of confidentiality at least as restrictive as
       Clauses 5.6 and 5.7 and which apply to the Disclosing Party's
       information.

5.9    [_]

In all other cases Xenova shall be entitled to supply:

       (c)    master and working CR2 cell lines: master and working dH2A virus;
              or master and working dH2T virus only to third party licensees
              appointed by Xenova under the Xenova Intellectual Property Rights;
              and

       (d)    all other Xenova Materials to any third party

       in each case only under appropriate and binding obligations of
       confidentiality which are no less onerous than those set out in this
       Agreement, and in each case Xenova shall notify Oxxon of the name of the
       third party to whom the supply has been made within 30 days of making
       such supply.

6.     PAYMENTS

6.1    Initial payment. Oxxon shall pay to Xenova a non-refundable,
       non-creditable, initial licence fee of [_]. Subject to Clause 6.2, this
       licence fee will be paid [_] shall be due even if this Agreement is
       terminated for any reason prior to the due date of payment:

                                       16





                                                                    Confidential

       (a)    [_] forthwith upon signature of this Agreement and receipt by
              Oxxon at an invoice for such amount suitable for VAT purposes; and

       (b)    [_] by the [_] of the Commencement Date; and

       (c)    [_] by the [_] of the Commencement Date.

6.2    [_]



                                       17





                                                                    Confidential


6.3    Milestone payments. Oxxon shall pay to Xenova the following
       non-refundable, non-creditable milestone payments for the [_] Licensed
       Products to achieve the following milestone events in either Field A or
       Field B. For the avoidance of doubt, such payments are due: (a) on the
       [_] Licensed Products to achieve each milestone event, whether or not
       these were the same [_] Licensed Products that achieved an earlier
       milestone event; and (b) irrespective of whether Oxxon sub-licenses any
       rights under this Agreement. For the avoidance of doubt, no further
       milestone payments are due other than those payable for the [_] Licensed
       Products.



       -------------------------------------------------------------------------------------------------------
       MILESTONE EVENT                                      LICENSED PRODUCT IN       LICENSED PRODUCT IN
                                                            FIELD A (MILLION          FIELD B (MILLION
                                                            POUNDS STERLING)          POUNDS STERLING)
       -------------------------------------------------------------------------------------------------------
                                                                                 
       [_]                                                  [_]                       [_]
       -------------------------------------------------------------------------------------------------------
       Filing of application for Marketing                  [_]                       [_]
       Authorisation in USA
       -------------------------------------------------------------------------------------------------------
       Grant of Marketing Authorisation in USA              [_]                       [_]
       -------------------------------------------------------------------------------------------------------
       Filing of application for Marketing                  [_]                       [_]
       Authorisation in any part of European Union
       -------------------------------------------------------------------------------------------------------
       Grant of Marketing Authorisation in any part of      [_]                       [_]
       the European Union
       -------------------------------------------------------------------------------------------------------
       Filing of application for Marketing                  [_]                       [_]
       Authorisation in Japan
       -------------------------------------------------------------------------------------------------------
       Grant of Marketing Authorisation in Japan            [_]                       [_]
       -------------------------------------------------------------------------------------------------------
       TOTAL                                                [_]                       [_]
       -------------------------------------------------------------------------------------------------------



                                       18





                                                                    Confidential

6.4    Opt-in Fees. Oxxon shall pay to Xenova:

       (a)    [_] per annum, commencing on the [_] of the Commencement Date and
              ending on the [_] of the Commencement Date, as an annual fee for
              the continued grant of rights under Clause 4.3(d)(i); and

       (b)    [_] per annum for each year commencing on the [_] of the
              Commencement Date that Oxxon elects to extend its opt-in rights
              pursuant to Clause 4.3(d)(ii), as an annual fee for the continued
              grant of the rights under Clause 4.3(d)(ii); and

       (c)    an opt-in fee of [_] for each Indication and Further Indication
              that Oxxon selects in Field A under Clause 4.3(d), and payable at
              the time of selection of such Indication or Further Indication;
              and

       (d)    an opt-in fee of [_] for each Indication and Further Indication
              that Oxxon selects in Field B under Clause 4.3(d) and payable at
              the time of selection of such Indication or Further Indication.


6.5    Royalties on Net Sales. Oxxon shall pay to Xenova a royalty that will be
       a percentage of Net Sales Value of each unit of Licensed Product sold by
       Oxxon or its Affiliates, as set out in the following table, depending on
       whether the Licensed Product is the first, second or subsequent product
       in Field A or Field B, respectively, and subject to the minimum
       percentages, after any deductions are made under other provisions of this
       Agreement, set out in the third column of the following table.
       Notwithstanding the foregoing and subject to Clause 10.1, in any country
       where there are no Xenova Patent Rights or in any country where the
       Xenova Patent Rights have expired or been revoked without a right of
       further appeal, all royalties and the relevant minimums set out below
       shall be reduced by 50%.



       ------------------------------------------------------------------------------------------------------
       LICENSED PRODUCTS IN FIELD A            % OF NET SALES VALUE             MIN. % OF NET SALES VALUE
       ------------------------------------------------------------------------------------------------------
                                                                          
       First Licensed Product                  [_]                              [_]
       ------------------------------------------------------------------------------------------------------
       Second Licensed Product                 [_]                              [_]
       ------------------------------------------------------------------------------------------------------
       Subsequent Licensed Products            [_]                              [_]
       ------------------------------------------------------------------------------------------------------
       LICENSED PRODUCTS IN FIELD B
       ------------------------------------------------------------------------------------------------------
       First Licensed Product                  [_]                              [_]
       ------------------------------------------------------------------------------------------------------
       Second Licensed Product                 [_]                              [_]
       ------------------------------------------------------------------------------------------------------
       Subsequent Licensed Products            [_]                              [_]
       ------------------------------------------------------------------------------------------------------


6.6    Royalties on Upfront and Royalty Receipts. Oxxon shall pay to Xenova, in
       respect of each Licensed Product and each Selected Indication that Oxxon
       sub-licenses the following sums provided that Oxxon shall not be required
       to pay sums under this Clause 6.6 in respect of sums receivable from
       Sub-licensees which are also its Affiliates if Oxxon is required to pay
       under Clause 6.5 in respect of such sums:


                                       19





                                                                    Confidential

       (a)    A percentage of any Upfront Receipts which shall be:

              (i)    [_] if the agreement, under which the Upfront Receipts are
                     due, is signed before completion of all Phase II Studies in
                     respect of that Licensed Product in that Selected
                     Indication; or

              (ii)   [_] if the agreement, under which the Upfront Receipts are
                     due, is signed after completion of all Phase II Studies in
                     respect of that Licensed Product in that Selected
                     Indication;

              Provided that:

              (iii)  where any consideration that falls within the definition of
                     Upfront Receipts is attributable to both Licensed
                     Product(s) and other products licensed by Oxxon or any of
                     its Affiliates to any other person, the percentages
                     referred to above shall be calculated on a reasonable
                     proportion of such consideration (the "Apportionment"); and

              (iv)   the Parties will negotiate in good faith to determine the
                     Apportionment (where applicable) and (whether or not any
                     Apportionment is required) to arrive at a reasonable
                     methodology to assess any amounts that may be due under
                     paragraphs (b) to (e) of the definition of Upfront
                     Receipts, and if the Parties cannot agree on (1) the
                     Apportionment, or (2) the methodology, within 60 days of
                     commencing such negotiations, or if the Parties at any time
                     during the term of this Agreement cannot agree on the
                     amount due under this paragraph (a) based on the
                     Apportionment or such methodology, either Party may refer
                     the matter to an expert to be appointed in accordance with
                     the provisions of Schedule 4.

       (b)    A percentage of Royalty Receipts, as set out in the second column
              of the following table, the percentage depending on when the
              agreement under which the Royalty Receipts are due is signed (as
              set out in the first column below), and subject to the conditions
              that:

              (i)    the royalty paid to Xenova on each Licensed Product under
                     this paragraph (b) shall be not less than the minimum
                     percentages of Net Sales Value, after any deductions are
                     made under other provisions of this Agreement, as set out
                     in the third column below; and

              (ii)   in the case only of the [_]% royalty on Royalty Receipts
                     referred to in the following table, the royalty paid to
                     Xenova on each Licensed Product under this paragraph (b)
                     shall not exceed a maximum of [_] of Net Sales Value,
                     except that this maximum limit shall not apply to
                     DISC-GMCSF which has not been genetically modified by Oxxon
                     or its Sub-licensees).

              Provided that:

                                       20





                                                                    Confidential

              (iii)  where any Royalty Receipts are attributable to any
                     Combination Product (as defined in Clause 6.7.1) or other
                     products or rights (other than Arising Intellectual
                     Property) licensed by Oxxon or any of its Affiliates to any
                     Sublicensees the percentages referred to above shall be
                     calculated on a reasonable proportion of such consideration
                     (the "Apportionment"); and

              (iv)   the Parties will negotiate in good faith to determine the
                     Apportionment (where applicable) and (whether or not any
                     Apportionment is required) to arrive at a reasonable
                     methodology to assess any amounts that may be due under
                     this Clause 6.6(b), and if the Parties cannot agree on (1)
                     the Apportionment, or (2) the methodology, within 60 days
                     of commencing such negotiations, or if the Parties at any
                     time during the term of this Agreement cannot agree on the
                     amount due under this paragraph (a) based on the
                     Apportionment or such methodology, either Party may refer
                     the matter to an expert to be appointed in accordance with
                     the provisions of Schedule.



       -----------------------------------------------------------------------------------------------------------
       AGREEMENT SIGNED ON OR BEFORE THE START     %OF            MIN. % OF NET SALES VALUE
       OF THE FOLLOWING STAGES, IN RESPECT OF      ROYALTY
       THE LICENSED PRODUCT AND SELECTED           RECEIPTS
       INDICATIONS ON WHICH ROYALTY RECEIPTS
       ARE OBTAINED
       -----------------------------------------------------------------------------------------------------------
                                                            
       Pre-Clinical Studies                        [_]            [_] (for DISC-GMCSF which has not been
                                                                  genetically modified by Oxxon or its
                                                                  Sub-licensees) [_] (for all other Licensed
                                                                  Products)
       -----------------------------------------------------------------------------------------------------------
       Phase I Studies                             [_]            [_] (for DISC-GMCSF which has not been
                                                                  genetically modified by Oxxon or its
                                                                  Sub-licensees) [_] (for all other Licensed
                                                                  Products in Field A) [_] (for all other
                                                                  Licensed Products in Field B)
       -----------------------------------------------------------------------------------------------------------
       Phase II Studies or later                    [_]           [_] (for DISC-GMCSF which has not been
                                                                  genetically modified by Oxxon or its
                                                                  Sub-licensees) [_] (for all other Licensed
                                                                  Products in Field A) [_] (for all other
                                                                  Licensed Products in Field B)
       -----------------------------------------------------------------------------------------------------------



                                       21




                                                                    Confidential

6.7    Combination Products

6.7.1  If any Licensed Product is incorporated in or with any other product as a
       single formulated product or is sold as part of a package or kit
       ("Combination Product") supplied by Oxxon or its Sub-licensee and the
       Licensed Product is not priced independently from the Combination
       Product, the Net Sales Value of such Licensed Product shall be deemed to
       be [_].

6.7.1  The Parties acknowledge and agree that (a) where a Licensed Product is
       supplied or used as a prime or boost as part of a Heterologous PrimeBoost
       regime, Net Sales Value and Royalty Receipts shall be calculated by
       reference to [_]; and (b) that this method of calculation is convenient
       to both Parties and is the basis for the agreed royalty rates for
       Licensed Product in Field A set out in this Agreement.

6.8    Payment dates. Royalties due under this Agreement shall be paid within 60
       days of the end of each quarter ending on 31 March, 30 June, 30 September
       and 31 December, in respect of sales of Licensed Product(s) made and
       Upfront Receipts and Royalty Receipts received during such quarter and
       within 60 days of the termination of this Agreement.

6.9    Payment terms. All sums due under this Agreement:

       (a)    are exclusive of Value Added Tax which where applicable will be
              paid by Oxxon to Xenova in addition;

       (b)    shall be paid in pounds sterling and, in the case of sales or
              sub-licence income received by Oxxon in a currency other than
              pounds sterling, the income shall be calculated in the other
              currency and then converted into equivalent pounds sterling at the
              buying rate of such other currency as quoted by Barclays Bank plc
              in London as at the close of business on the last business day of
              the quarterly period with respect to which the payment is made;

       (c)    shall be made without deduction of income tax or other taxes,
              charges or duties that may be imposed, except insofar as Oxxon is
              required to deduct the same to comply with applicable laws. The
              Parties shall cooperate and take all steps reasonably and lawfully
              available to them to avoid deducting such taxes and to obtain
              double taxation relief. If Oxxon is required to make any such
              deduction it shall provide Xenova with such certificates or other
              documents as it can reasonably obtain to enable Xenova to obtain
              appropriate relief from double taxation of the payment in
              question; and

       (d)    shall be made by the due date, failing which Xenova may charge
              interest on any outstanding amount on a daily basis at a rate
              equivalent to [_] above the Barclays Bank plc base lending rate
              then in force.

                                       22



                                                                    Confidential

6.10   Exchange controls, etc. If at any time during the continuation of this
       Agreement Oxxon is prohibited from making any of the payments required
       hereunder by a governmental authority in any country then Oxxon will
       within the prescribed period for making the said payments in the
       appropriate manner use its best endeavours to secure from the proper
       authority in the relevant country permission to make the said payments
       and will make them within 7 days of receiving such permission. If such
       permission is not received within 30 (thirty) days of Oxxon making a
       request for such permission then, at the option of Xenova, Oxxon shall
       deposit the royalty payments due in the currency of the relevant country
       either in a bank account designated by Xenova within such country or such
       royalty payments shall be made to an associated company of Xenova
       designated by Xenova and having offices in the relevant country
       designated by Xenova.

6.11   Royalty statements. Oxxon shall send to Xenova at the same time as each
       royalty payment is made in accordance with Clause 6.8 a statement setting
       out, (i) in respect of each territory or region in which Licensed
       Product(s) are sold, the types of Licensed Product(s) sold, the quantity
       of each type sold, and the total Net Sales Value in respect of each type,
       expressed both in local currency and pounds sterling and showing the
       conversion rates used, (ii) Royalty Receipts; and (iii) Upfront Receipts
       during the period to which the royalty payment relates.

6.12   Records

6.12.1 Oxxon shall keep at its normal place of business detailed and up to date
       records and accounts showing the quantity, description and value of
       Licensed Product(s) sold by it, and the amount of sublicensing revenues
       received by it in respect of Licensed Product(s), on a country by country
       basis, and being sufficient to ascertain the payments due under this
       Agreement.

6.12.2 Oxxon shall no more than once in any 12 month period make such records
       and accounts available, on reasonable notice, for inspection during
       business hours by an independent chartered accountant nominated by Xenova
       for the purpose of verifying the accuracy of any statement or report
       given by Oxxon to Xenova under Clause 6.11. The accountant shall be
       required to keep confidential all information learnt during any such
       inspection, and to disclose to Xenova only such details as may be
       necessary to report on the accuracy of Oxxon's statement or report.
       Xenova shall be responsible for the accountant's charges unless the
       accountant certifies that there is an inaccuracy of more than 5% (five
       percent) in any royalty statement, in which case Oxxon shall pay his
       charges in respect of that inspection.

7      DILIGENCE

7.1    Oxxon shall use Reasonable and Diligent Efforts to develop and
       commercially exploit Licensed Product(s) in the Territory.


7.2    [_]


                                       23




                                                                    Confidential

7.3    Without prejudice to the generality of Oxxon's obligations under Clause
       7.1, Xenova may terminate this Agreement from time to time with respect
       to a Selected Indication (but not with respect to other Indications):

       (a)    If Oxxon is in breach of its obligations under Clause 7.1 with
              respect to such Selected Indication; or

       (b)    In any event, and without prejudice to the generality of Oxxon's
              obligations under this Clause 7, if Oxxon substantially abandons
              its development work with respect to such Selected Indication for
              a period of two years.

7.4    If Xenova considers at any time during the period of this Agreement that
       Oxxon has without legitimate reason failed to use Reasonable and Diligent
       Efforts to develop and commercially exploit Licensed Product(s) in
       accordance with this Clause 7, Xenova shall, prior to exercising any
       right of termination under Clause 7, refer to an independent expert (or
       experts) the following questions:

       (a)    whether Oxxon has used Reasonable and Diligent Efforts; and if not

       (b)    whether the proposals submitted by Oxxon to such expert are
              adequate to meet Oxxon's requirement to use Reasonable and
              Diligent Efforts, and if not

       (c)    what actions the expert proposes Oxxon should take in order to
              meet the requirement to use Reasonable and Diligent Efforts.

7.5    The independent expert (or experts) shall be appointed in accordance with
       the provisions of Schedule 4.

7.6    If the expert(s) determines that Oxxon has failed to comply with its
       obligations under this Clause 7, and if Oxxon fails to take the actions
       proposed by Oxxon pursuant to Clause 7.4(b) or suggested by the expert(s)
       pursuant to Clause 7.4(c) (as appropriate) within 6 months of the
       expert(s) giving his/their decision in accordance with Schedule 4, Xenova
       shall be entitled, by giving, at any time within 3 months after the end
       of that 6 month period, not less than 3 months' notice to terminate this
       Agreement as a whole or in relation to a Selected Indication (as
       appropriate).

7.7    The provisions of Clauses 7.2 to 7.6, and the exercise of the rights
       under those clauses, shall be without prejudice to any rights that Xenova
       may have to claim damages in the event that Oxxon is in breach of any of
       its obligations under Clause 7.1. In the event of a damages claim, any
       finding of the expert under Clause 7.4(a) shall not be binding on the
       Parties.

8.     INTELLECTUAL PROPERTY

8.1    Obtain and maintain the Xenova Patent Rights. Xenova shall:

       (a)    Diligently seek to obtain valid patents in the name of Xenova
              pursuant to each of the patent applications listed in Schedule 1.
              Xenova shall keep Oxxon informed of the progress of such patent
              applications and shall take account of Oxxon's reasonable views in
              relation to all major decisions affecting patent prosecution (but
              shall not be

                                       24




                                                                    Confidential

              required to delay such decisions in order to do so) and provided
              that if the Parties cannot agree Xenova shall have the final say
              on all matters relating to such patent prosecution; and

       (b)    pay all renewal fees in respect of the Xenova Patent Rights as and
              when due.

       Oxxon shall reimburse [_] of Xenova's costs and expenses in relation to
       such activities save that if Xenova grants any licenses to third parties
       under the Xenova Patent Rights it shall notify Oxxon and the patent costs
       reimbursed by Oxxon shall be reduced proportionately by the number of
       additional licensees. For example, if Xenova appoints one additional
       licensee then Oxxon's obligation to reimburse patent costs would be
       reduced to [_], if two additional licensees were appointed then
       Oxxon's obligation to reimburse patent costs would be reduced to [_]. For
       the avoidance of doubt Oxxon shall not be required to reimburse to Xenova
       (i) any patent costs and expenses to the extent that such costs or
       expenses relate solely to prosecution or other activities affecting the
       Xenova Patent Rights outside the Field; and/or (ii) any of Xenova's costs
       in respect of Revocation Proceedings or proceedings of a similar nature
       that Xenova initiates.

       (c)    if Oxxon wishes to cease reimbursing its share of the costs of any
              application in respect of the Xenova Patent Rights or of the
              maintenance of any such Patent it shall give 3 months' prior
              written notice to Xenova and on the expiry of such notice period
              Oxxon shall cease to be licensed under the patent application or
              patent identified in the notice. If the patent application or
              patent identified in the notice is the sole remaining Xenova
              Patent Right in the country or territory of that patent then Oxxon
              shall cease to be licensed under any other Xenova Intellectual
              Property in the country or territory of such patent application or
              patent, in which case this Agreement shall terminate in respect of
              such country or territory and Oxxon shall have no further
              obligations under this Agreement in respect of such country or
              territory.

8.2    Obtain and maintain the Arising Patents. Oxxon shall notify Xenova of any
       inventions made by Oxxon or its Affiliates that relate to any of the
       Xenova Intellectual Property or any Licensed Product ("Arising
       Inventions") and the provisions of Clause 4.4.2 in respect of licensing
       such Arising Patents to Xenova shall apply. For the avoidance of doubt
       Oxxon shall be solely responsible for the costs of any patent
       applications and patents that it elects to file in respect of Arising
       Inventions.

8.3    Infringement of the Patents

8.3.1  Each Party shall inform the other Party promptly if it becomes aware of
       any infringement or potential infringement of any of the Patents in the
       Field, and the Parties shall consult with each other to decide the best
       way to respond to such infringement.

8.3.2  If the Parties fail to agree on a joint programme of action, including
       how the costs of any such action are to be borne and how any damages or
       other sums received from such action are to be distributed, then Oxxon
       shall have the first right, but not the obligation to take action in
       respect of any infringements of the Patents in the Field, including
       conducting infringement actions in its own name at Oxxon's sole expense
       and Oxxon shall be entitled to all damages or other sums received from
       such action, after reimbursing Xenova for any reasonable expenses
       incurred in assisting it in such action, and subject to paying Xenova
       royalties based on the amount of such damages or sums as if it were the
       amount of Net

                                       25





                                                                    Confidential

       Sales Value of Licensed Product(s), in accordance with Clause 6.5. If the
       alleged infringement is both within and outside the Field, the Parties
       shall also co-operate with Xenova's other licensee's (if any) in relation
       to any such action and shall divide the costs of such action
       proportionately among Oxxon and Xenova's other licensee's who participate
       in such action. To the extent that patent law requires Oxxon to bring any
       such action in Xenova's name or the name of a Xenova Affiliate, Oxxon may
       do so subject to the conditions that it shall:

       (a)    before commencing any such action in Xenova's name or the name of
              a Xenova Affiliate (as appropriate), provide Xenova with an
              effective indemnity against any costs that may be incurred by
              Xenova or awarded against Xenova as a result of being a party to
              any such action;

       (b)    not act, nor hold itself out as acting, as an agent or with the
              authority of Xenova in respect of such action; and

       (c)    not make any statement in relation to such action or any
              settlement thereof that may reasonably be considered to be
              damaging to Xenova's reputation, except with Xenova's prior
              written agreement such consent not to be unreasonably withheld or
              delayed.

8.4    Infringement of third party rights

8.4.1  If any warning letter or other notice of infringement is received by a
       Party, or legal suit or other action is brought against a Party, alleging
       infringement of third party rights in the manufacture, use or sale of any
       Licensed Product or use of any Patents, that Party shall promptly provide
       full details to the other Party.

8.4.2  Oxxon shall have the right but not the obligation to defend such suit in
       the Field and shall have the right to settle with such third party,
       provided that if any action or proposed settlement involves the making of
       any statement, express or implied, concerning the validity of any Patent,
       the consent of Xenova must be obtained before taking such action or
       making such settlement, such consent not to be unreasonably withheld or
       delayed.

8.5    Revocation Proceedings

8.5.1  Xenova shall promptly notify Oxxon of the commencement of any Revocation
       Proceedings.

8.5.2  Xenova shall have the right but not the obligation to defend the
       Revocation Proceedings.

8.5.3  If Xenova does not wish to defend or continue to defend Revocation
       Proceedings then Xenova shall promptly notify Oxxon and Oxxon may at
       Oxxon's own cost and expense defend or continue to defend the Revocation
       Proceedings referred to in Xenova's notice.

8.5.4  Each party shall provide the other party with such assistance as the
       other party shall reasonably request in connection with any Revocation
       Proceedings. The party requesting such assistance shall pay the other
       party's reasonable out-of-pocket expenses properly incurred in providing
       the requested assistance.

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8.6    Third party intellectual property.

8.6.1  For the avoidance of doubt Oxxon shall be solely responsible for
       obtaining and paying for any additional licences and other rights that
       may be required to enable Oxxon, its Affiliates or Sub-licensees to
       commercialise Licensed Product(s) in the Territory. Except as provided
       for in Clause 8.6.2, no deductions may be made in respect of any such
       payments when determining the amount of any payment due to Xenova under
       this Agreement.

8.6.2  If, during the continuation of this Agreement, Oxxon or any Affiliate or
       any Sub-licensee considers it necessary to obtain a licence from any
       independent third party ("Third Party Licence") in order to avoid
       infringing such third party's patent(s) in the course of manufacture or
       sale of any Licensed Product, royalty amounts to be paid pursuant to
       Clause 6.5 or 6.6 shall be reduced by an amount equal to [_] of the total
       amount actually paid under the Third Party Licence provided that
       royalties payable by Oxxon to Xenova on any unit of Licensed Product,
       after applying the deduction referred to in this Clause 8.6.2 and any
       other deductions provided for under this Agreement shall not be reduced
       below the minimum royalty rates set out in the third column of the table
       in Clause 6.5 or the third column of the table in Clause 6.6, as
       applicable, assuming that no such deductions had been made when
       calculating such minimum royalties.

9.     WARRANTIES AND LIABILITY

9.1    Warranties by Xenova, Xenova warrants and undertakes to Oxxon that as at
       the Commencement Date, and except as referred to in Schedule 5:

       (a)    it is the beneficial owner of the Xenova Patent Rights and the
              Xenova Materials and that there are no liens, encumbrances,
              options or other charges over any of them (and for the avoidance
              of doubt references in this paragraph (a) to liens and
              encumbrances do not refer to intellectual property other than the
              Xenova Intellectual Property);

       (b)    Xenova Research Limited is the legal owner of the Xenova Patent
              Rights;

       (c)    it and its Affiliates have not done, and Xenova will not do nor
              agree to do and will procure that its Affiliates do not nor agree
              to do during the continuation of this Agreement, any of the
              following things if to do so would adversely affect Oxxon's
              ability to exercise the rights granted to it under this Agreement,
              namely:

              (i)    grant or agree to grant any rights in the Xenova
                     Intellectual Property in the Field; or

              (ii)   assign, mortgage, charge or otherwise transfer any of the
                     Xenova Patent Rights in the Field; and

       (d)    so far as the Xenova Representatives are aware, but without having
              conducted any searches or investigations other than those
              disclosed to Oxxon, no third party owns or claims any rights in
              the Xenova Patent Rights; and

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       (e)    so far as the Xenova Representatives are aware, but without having
              conducted any searches or investigations other than those
              disclosed to Oxxon, there are no allegations or proceedings,
              pending or threatened which challenge Xenova's or Xenova's
              Affiliates' exclusive ownership, the validity or the
              enforceability of the Xenova Patent Rights that could adversely
              affect the rights granted to Oxxon under this Agreement; and

       (f)    Schedule 1 is a complete and accurate list of all the patents
              owned or licensed to Xenova or any Affiliate of Xenova that may be
              required for the full exercise of Oxxon's rights under this
              Agreement. If Schedule 1 is found during the term of this
              Agreement to be incomplete, with the effect that Oxxon requires a
              licence of any further patents that at the Commencement Date are
              owned by or licensed to Xenova or any Affiliate of Xenova in order
              to exercise Oxxon's rights under this Agreement then Xenova shall
              or shall procure the grant of such licence to Oxxon and the grant
              of such licence shall be Oxxon's sole and exclusive remedy for any
              breach by Xenova of the provisions of this Clause 9.1 (f); and

       (g)    Xenova has provided or made available to Oxxon all significant
              test data generated by Xenova or any Affiliate of Xenova relating
              to the Xenova Materials.

       (h)    Xenova has the right to grant to Oxxon a licence under the Xenova
              Intellectual Property in accordance with the provisions of this
              Agreement and to meet its obligations under this Agreement in
              respect of such Xenova Intellectual Property. In the event that
              Xenova is unable to comply with its obligations under this
              Agreement in respect of any of the Xenova Intellectual Property as
              it is not the legal owner, it shall procure that such of its
              Affiliates as is the legal owner of such Xenova Intellectual
              Property complies with Xenova's obligations on Xenova's behalf.

       (i)    Schedule 5 Part 1 sets out a complete and accurate list of all
              third parties to whom Xenova has licensed Xenova Intellectual
              Property.

       (j)    Schedule 5 Part 2 sets out a complete and accurate list of all
              third parties to whom Xenova has supplied master and working CR2
              cell lines: master and working dH2A virus; or master and working
              dH2T virus. Such supply has been made under appropriate and
              binding obligations of confidentiality.

       (k)    Schedule 5 Part 3 sets out, so far as the Xenova Representatives
              are aware, a complete and accurate list of all third parties to
              whom Xenova has supplied any Xenova Materials other than those
              referred to in Clause 9.1 (j). Such supply of the Xenova Material
              has been made solely for non-commercial use under appropriate and
              binding obligations of confidentiality.

       (1)    As far as Xx Xxxxx Xxxxxxxxxx and Xx Xxxxxxxxx Xxxxxxxxx are aware
              Xenova has disclosed to Oxxon all material searches relating to
              the Xenova Intellectual Property that have been carried out by or
              on behalf of Xenova and they are not aware of any past disputes,
              litigation, interference or opposition proceedings relating to the
              Xenova Intellectual Property other than those disclosed to Oxxon.


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9.2    No other warranties

9.2.1  Each of Oxxon and Xenova acknowledges that, in entering into this
       Agreement, it does not do so in reliance on any representation, warranty
       or other provision except as expressly provided in this Agreement, and
       any conditions, warranties or other terms implied by statute or common
       law are excluded from this Agreement to the fullest extent permitted by
       law.

9.2.2  Without limiting the scope of Clause 9.2.1 and subject to Clause 9.1,
       Xenova does not give any warranty, representation or undertaking:

       (a)    as to the technical viability of any products made or processes
              carried out using any of the Xenova Intellectual Property; or

       (b)    that any of the Xenova Patent Rights is or will be valid or
              subsisting or (in the case of an application) will proceed to
              grant; or

       (c)    as imposing any obligation on Xenova to bring or prosecute actions
              or proceedings against third parties for infringement or to defend
              any action or Revocation Proceedings.

9.2.3  Indemnity. Oxxon shall indemnify and hold harmless Xenova and its
       Affiliates and their respective officers, employees, consultants, agents
       and representatives (the "Indemnitees") against all third party claims
       which may be asserted against or suffered by any of the Indemnitees
       arising out of any possession or use by a third party of any Licensed
       Produces) manufactured and/or supplied by Oxxon or its Sub-licensees.

9.2.4  The indemnity given by Oxxon pursuant to Clause 9.2.3 shall be subject to
       the following conditions:

       (a)    Xenova shall notify Oxxon of any claim or action covered by the
              indemnity (a "Claim") within 14 days of becoming aware of the
              Claim;

       (b)    the Claim does not arise as a consequence of any breach of any of
              Xenova's warranties as set out in Clause 9.1 of this Agreement
              and/or from any negligence or wilful misconduct by Xenova;

       (c)    Oxxon is given sole conduct of the defence and settlement of any
              Claim;

       (d)    Xenova does not at any time prejudice the defence of the Claim;
              and

       (e)    Xenova provides Oxxon (at Oxxon's cost) with such assistance,
              documents, authority and information as Oxxon may reasonably
              require in relation to the Claim and the defence or settlement of
              the Claim.

9.3    Liability. Subject to Clause 11.12, but notwithstanding any other
       provision of this Agreement, no Party shall be liable to any other Party
       to this Agreement in contract, tort, negligence, breach of statutory duty
       or otherwise for any loss, damage, costs or expenses of any nature
       whatsoever incurred or suffered by that other party or its Affiliates of
       an indirect or consequential nature including without limitation any
       economic loss or other loss of turnover, profits, business or goodwill.

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10.    DURATION AND TERMINATION

10.1   Commencement and Termination by Expiry. This Agreement, and the licences
       granted hereunder, shall come into effect on the Commencement Date and,
       unless terminated earlier in accordance with this Clause 10, shall
       continue in force on a country by country basis until the later of:

       (a)    the date on which all the Xenova Patent Rights in such country (or
              countries) have expired or been revoked without a right of further
              appeal; and

       (b)    the later of:

              (i)    the [_] anniversary of the first commercial sale of
                     Licensed Product(s); and

              (ii)   the [_] anniversary of the date of such expiry or
                     revocation;

       provided that this Agreement shall [_] is marketed in such country;

       and on such date this Agreement and the licences granted hereunder shall
       terminate automatically by expiry. On expiry of this Agreement in any
       country pursuant to Clause 10.1 Xenova [_].

10.2   Early termination

10.2.1 Oxxon may terminate this Agreement at any time on [_] notice in
       writing to Xenova.

10.2.2 Without prejudice to any other right or remedy, either Party may
       terminate this Agreement at any time by notice in writing to the other
       Party ("Other Party"), such notice to take effect as specified in the
       notice:

       (a)    if the Other Party is in material breach of this Agreement and, in
              the case of a breach capable of remedy within [_], the breach
              is not remedied within [_] of the Other Party receiving notice
              specifying the breach and requiring its remedy; or

       (b)    if an order is made or a resolution passed for the winding up of
              the other party (other than for the purpose of a solvent scheme of
              reconstruction or amalgamation);

       (c)    a liquidator, administrative receiver, receiver or trustee is
              appointed in respect of a material part of the other party's
              assets or business;

       (d)    as a consequence of financial difficulties the other party makes
              any voluntary arrangement with its creditors;

       (e)    the other party ceases to continue its business;

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       (f)    as a consequence of debt and/or maladministration, the other party
              takes or suffers any similar or analogous action to those listed
              in Clauses 10.2.2(b) to 10.2.2(e).

10.2.3 Xenova may forthwith terminate this Agreement by giving written notice to
       Oxxon if Oxxon or its Affiliate or sub-licensee commences legal
       proceedings, or assists any third party to commence legal proceedings, to
       challenge the validity of any of the Patents.

10.3   Consequences of termination

10.3.1 Upon termination or expiry of this Agreement for any reason:

       (a)    if termination occurs after the first commercial sale of Licensed
              Product(s), Oxxon and its Sub-licensees shall be entitled to sell,
              use or otherwise dispose of (subject to payment of royalties under
              Clauses 6.5 and 6.6) any unsold or unused stocks of the Licensed
              Product for a period of 6 months following the date of
              termination; and if termination occurs prior to the first
              commercial sale of Licensed Product, Oxxon shall forthwith return
              all such stocks of Licensed Product, Xenova Materials and Xenova
              Know-how to Xenova free of charge. For the avoidance of doubt, in
              the event of expiry of this Agreement nothing in this Agreement
              shall restrict Oxxon's ability to supply Licensed Products;

       (b)    subject to paragraph (a) above and Clause 10.1, Oxxon shall no
              longer be licensed to use or otherwise exploit in any way, either
              directly or indirectly, any of the Xenova Intellectual Property;

       (c)    subject to paragraph (a) above, Oxxon shall consent to the
              cancellation of any formal licence granted to it, or of any
              registration of it in any register, in relation to any of the
              Xenova Patent Rights;

       (d)    the provisions of Clauses 5.6 to 5.8 (except that neither Party
              shall have any continuing right to use any of the other Party's
              confidential information save as provided in Clause 10.1), 6 (in
              respect of payments arising prior to termination or under Clause
              6.1 or 6.2 or under paragraph (a) above), 9,10.1 (to the extent
              such clause refers to a post termination licence) 10.3 and 11
              shall continue in force; and

       (e)    subject as provided in this Clause 10.3.1 and 10.3.2 and 10.3.3,
              and except in respect of any accrued rights, neither Party shall
              be under any further obligation to the other,

10.3.2 Upon termination of this Agreement for any reason otherwise than in
       accordance with Clause 10.1 and at Xenova's request, Xenova shall have
       the exclusive right for a period of 90 days from the date of termination
       to negotiate in good faith the terms of an agreement between the parties
       on reasonable commercial terms under which Oxxon would:

       (a)    transfer to Xenova all clinical and other data relating to the
              development of Licensed Product(s);

       (b)    to the extent possible, seek to have any product licences, pricing
              approvals and other permits and applications transferred into the
              name of Xenova or its nominee;

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       (c)    grant Xenova an exclusive, worldwide licence, with the right to
              grant sub- licences, under all Arising Intellectual Property and
              any improvements and other intellectual property owned or
              controlled by Oxxon relating to the Licensed Product(s); and

       (d)    grant Xenova or its nominee the right to continue to use any
              product name that had been applied to the Licensed Product(s)
              prior to termination of this Agreement.

10.3.3 If the Parties are unable to agree the terms of an agreement as described
       in Clause 10.3.2 within 90 days of the date of termination then either
       party may refer the terms for settlement by an independent expert who
       shall be appointed in accordance with the provisions of Schedule 4. The
       Parties shall promptly execute an agreement on the terms agreed between
       them or settled by the expert.

11.    GENERAL

11.1   Force majeure. Neither Party shall have any liability or be deemed to be
       in breach of this Agreement for any delays or failures in performance of
       this Agreement which result from circumstances beyond the reasonable
       control of that Party, including without limitation labour disputes
       involving that Party. The Party affected by such circumstances shall
       promptly notify the other Party in writing when such circumstances cause
       a delay or failure in performance and when they cease to do so.

11.2   Amendment. This Agreement may only be amended in writing signed by duly
       authorised representatives of Xenova and Oxxon.

11.3   Assignment and third party rights.

11.3.1 Subject to Clause 11.3.2, neither Party shall assign, mortgage, charge or
       otherwise transfer any rights or obligations under this Agreement, nor
       any of the Patents or rights under the Patents, without the prior written
       consent of the other Party.

11.3.2 Either Party may assign all its rights and obligations under this
       Agreement together with its rights in the Patents to any Affiliate of
       that Party (provided that such rights and obligations shall be assigned
       back to the original Party in the event that the assignee ceases to be an
       Affiliate of that Party) or to any company to which it transfers all or
       substantially all of its assets or business in the Field, provided that
       the assignee undertakes to the other Party to be bound by and perform the
       obligations of the assignor under this Agreement.

11.4   Waiver. No failure or delay on the part of either Party to exercise any
       right or remedy under this Agreement shall be construed or operate as a
       waiver thereof, nor shall any single or partial exercise of any right or
       remedy preclude the further exercise of such right or remedy.

11.5   Invalid Clauses. If any provision or part of this Agreement is held to be
       invalid, amendments to this Agreement may be made by the addition or
       deletion of wording as appropriate to remove the invalid part or
       provision but otherwise retain the provision and the other provisions of
       this Agreement to the maximum extent permissible under applicable law.

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11.6   No Agency. Neither Party shall act or describe itself as the agent of the
       other, nor shall it make or represent that it has authority to make any
       commitments on the other's behalf.

11.7   Interpretation. In this Agreement:

       (a)    the headings are used for convenience only and shall not affect
              its interpretation;

       (b)    references to persons shall include incorporated and
              unincorporated persons; references to the singular include the
              plural and vice versa; and references to the masculine include the
              feminine;

       (c)    references to Clauses and Schedules mean Clauses of, and Schedules
              to this Agreement;

       (d)    references to Xenova or Oxxon shall include their permitted
              successors and permitted assignees;

       (e)    where the word "including" is used, it shall be understood as
              meaning "including without limitation"; and

       (f)    references to the grant of "exclusive" rights shall mean that the
              person granting the rights shall neither grant the same rights (in
              the same Field and Territory) to any other person, nor exercise
              those rights directly to the extent that and for as long as the
              Licensed Product(s) are within Valid Claims of unexpired Patents
              or, to the extent that the Licensed Product(s) are protected by
              Know-how that has not become known to the public, for a period of
              10 years from the first commercial sale of Licensed Product(s) in
              any part of the Territory.

11.8   Notices

11.8.1 Any notice to be given under this Agreement shall be in writing and shall
       be sent by first class mail or air mail, or by fax (confirmed by first
       class mail or air mail) to the address of the relevant Party set out at
       the head of this Agreement, or to the relevant fax number set out below,
       or such other address or fax number as that Party may from time to time
       notify to the other Party in accordance with this Clause 11.8. The fax
       numbers of the Parties are as follows:

       Xenova-01753 706607
       Oxxon-01865 398101.

11.8.2 Notices sent as above shall be deemed to have been received three working
       days after the day of posting (in the case of inland first class mail),
       or seven working days after the date of posting (in the case of air
       mail), or on the next working day after transmission (in the case of fax
       messages, but only if a transmission report is generated by the sender's
       fax machine recording a message from the recipient's fax machine,
       confirming that the fax was sent to the number indicated above and
       confirming that all pages were successfully transmitted).

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11.9   Law and Jurisdiction. The validity, construction and performance of this
       Agreement shall be governed by English law and shall be subject to the
       exclusive jurisdiction of the English courts to which the parties hereby
       submit, except that a Party may seek an interim injunction in any court
       of competent jurisdiction.

11.10  Further action. Each Party agrees to execute, acknowledge and deliver
       such further instruments, and do all further similar acts, as may be
       necessary or appropriate to carry out the purposes and intent of this
       Agreement.

11.11  Announcements. Neither Party shall make any press or other public
       announcement concerning any aspect of this Agreement, or make any use of
       the name of the other Party in connection with or in consequence of this
       Agreement, without the prior written consent of the other Party, except
       as may be required by law or by the rules of any stock exchange on which
       either Party is listed. The Parties shall agree a form of press release
       for issue on signature of this Agreement.

11.12  Entire agreement. This Agreement, including its Schedules, sets out the
       entire agreement between the Parties relating to its subject matter and
       supersedes all prior oral or written agreements (including without
       limitation a material transfer agreement dated 14 November 2003),
       arrangements or understandings between them relating to such subject
       matter. The Parties acknowledge that they are not relying on any
       representation, agreement, term or condition that is not set out in this
       Agreement. Nothing in this Agreement shall operate to exclude or limit
       any liability, right or remedy to a greater extent than is permitted
       under English law including in relation to (1) death or personal injury
       caused by the negligence of a party or (2) fraudulent misrepresentation
       or deceit.

11.13  Third party rights. Each of the persons identified in Clause 9.2.3 may in
       his own right enforce the provisions of that Clause. Except as provided
       in the previous sentence of this Clause 11.13, this Agreement is not made
       for the benefit of, nor shall any of its provisions be enforceable by,
       any person other than the parties to this Agreement and their respective
       successors and permitted assignees

AGREED by the Parties through their authorised signatories:

For and on behalf of                            For and on behalf of
Xenova LIMITED                                  OXXON THERAPEUTICS LIMITED

/s/XXXXX OXLADE                                 /s/XXXXXXX XXXXXXXXX
_______________________________                 _______________________________
signed                                          signed

XXXXX OXLADE                                    XXXXXXX XXXXXXXXX
_______________________________                 _______________________________
print name                                      print name


CEO                                             PRESIDENT + CEO
_______________________________                 _______________________________
title                                           title


12.01.2005                                      02.02.2005
_______________________________                 _______________________________
date                                            date


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