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                        CONFIDENTIAL TREATMENT REQUESTED

                                                                    Exhibit 10.4

                             RESEARCH COLLABORATION

                              AND LICENCE AGREEMENT

                                 BY AND BETWEEN

                             ASTRAZENECA UK LIMITED

                                       AND

                             AVANIR PHARMACEUTICALS

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                                                                             (i)


TABLE OF CONTENTS

<TABLE>
<S>                                                                           <C>
1    DEFINITIONS..........................................................     1

2    CONSTRUCTION.........................................................    17

3    GRANT OF RIGHTS......................................................    17

4    CONFIRMATORY PATENT LICENCES.........................................    22

5    THE RESEARCH COLLABORATION...........................................    23

6    MANAGEMENT OF THE RESEARCH COLLABORATION.............................    27

7    REPORTS..............................................................    37

8    DEVELOPMENT PROJECT..................................................    38

9    RESEARCH FUNDING.....................................................    41

10   CONSIDERATION........................................................    43

11   REIMBURSEMENT OF DEVELOPMENT STOCK AND PRE-CLINICAL STUDIES..........    57

12   OWNERSHIP OF INTELLECTUAL PROPERTY...................................    60

13   ADVERSE EVENT REPORTING..............................................    62

14   CONFIDENTIALITY & NON-DISCLOSURE.....................................    62

15   TRADEMARKS...........................................................    67

16   REPRESENTATIONS, WARRANTIES AND COVENANTS............................    68

17   INDEMNITY............................................................    72

18   MAINTENANCE AND PROSECUTION OF PATENTS...............................    77

19   ENFORCEMENT OF PATENTS...............................................    81

20   POTENTIAL THIRD PARTY RIGHTS.........................................    83

21   TERM AND TERMINATION.................................................    86

22   FORCE MAJEURE........................................................    96

23   ASSIGNMENT...........................................................    97

24   SEVERABILITY.........................................................    99
</TABLE>

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                                                                            (ii)


<TABLE>
<S>  <C>                                                                     <C>
25   GOVERNING LAW; DISPUTE RESOLUTION....................................    99

26   INTERPRETATION OF CERTAIN EVIDENCE...................................   100

27   NOTICES..............................................................   101

28   RELATIONSHIP OF THE PARTIES..........................................   102

29   ENTIRE AGREEMENT.....................................................   102

30   ENGLISH LANGUAGE.....................................................   102

31   AMENDMENT............................................................   103

32   WAIVER AND NON-EXCLUSION OF REMEDIES.................................   103

33   EQUITABLE RELIEF.....................................................   103

34   FURTHER ASSURANCE....................................................   104

35   EXPENSES.............................................................   104
</TABLE>

SCHEDULES

Research Plan                                       Schedule 1
Licensed Know-How                                   Schedule 2
IND Filing Plan                                     Schedule 3
Licensed Patents and Applications                   Schedule 4
Confirmatory Patent Licenses                        Schedule 5
Key Personnel and AstraZeneca Principal Scientist   Schedule 6
Press Release                                       Schedule 7

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                        CONFIDENTIAL TREATMENT REQUESTED

                  RESEARCH COLLABORATION AND LICENCE AGREEMENT

This Research Collaboration and Licence Agreement (the "Agreement") is made
effective as of the 8th day of July 2005 (the "Effective Date") by and between:

(1)  ASTRAZENECA UK LIMITED, a company incorporated in England whose registered
     office is at 15 Stanhope Gate, London, WIK 1LN, England ("ASTRAZENECA");
     and

(2)  AVANIR PHARMACEUTICALS, a company incorporated in California, with offices
     at 11388 Sorrento Valley Road, Suite 200, San Diego, CA 92121, USA
     ("AVANIR").

RECITALS

(A)  WHEREAS, Avanir is engaged in research regarding reverse cholesterol
     transportation involving reverse cholesterol transport promotors, and
     Avanir has in the course thereof developed the AVP 26452 Compound and the
     Back-Up Compounds (as such terms are defined below); and

(B)  WHEREAS, AstraZeneca and its Affiliates have specialised experience in,
     among other things, the research, development, manufacturing and
     commercialisation of pharmaceutical compounds worldwide; and

(C)  WHEREAS, the Parties wish to engage in a research collaboration utilising
     the Parties' respective knowledge, skills and proprietary technology to
     develop the Back-Up Compounds or Collaboration Compounds (as defined below)
     up to the selection of Candidate Drug (as defined below); and

(D)  WHEREAS, the Parties wish AstraZeneca to be responsible, as a general
     matter, for clinical development and commercialisation of the AVP 26452
     Product (as defined below); and

(E)  WHEREAS, the Parties wish AstraZeneca, after the selection of Candidate
     Drug, to be responsible for developing and commercialising the Licensed
     Products (as defined below); and

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(F)  WHEREAS, the Parties wish to collaborate as set forth above, and Avanir
     desires to grant a licence to AstraZeneca, and AstraZeneca desires to take
     a licence, to develop and commercialise the Licensed Products, in
     accordance with the terms and conditions set forth below.

AGREEMENT

NOW, THEREFORE, in consideration of the mutual covenants contained in this
Agreement, and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the Parties, intending to be
legally bound, agree as follows:

1    DEFINITIONS

     Unless otherwise specifically provided herein, the following terms, when
     used with a capital letter at the beginning, shall have the following
     meanings:

1.1  "AFFILIATE" means, with respect to a Person, any Person that controls, is
     controlled by or is under common control with, such first Person. For
     purposes of this definition only, "control" means (a) to possess, directly
     or indirectly, the power to direct the management or policies of a Person,
     whether through ownership of voting securities, by contract relating to
     voting rights or corporate governance or otherwise, or (b) to own, directly
     or indirectly, more than fifty percent (50%) of the outstanding voting
     securities or other voting ownership interest of such Person.

1.2  "ANNUAL NET SALES" means the Net Sales made during a given Calendar Year.

1.3  "APPLICABLE LAW" means the applicable laws, rules and regulations,
     including any rules, regulations, guidelines or other requirements of the
     Health Authorities, that may be in effect from time to time in the
     Territory.

1.4  "ASTRAZENECA BACKGROUND TECHNOLOGIES" means any (a) Information, discovery,
     invention, products, cultures, biological materials and other materials and
     compositions (including Collaboration Materials provided by AstraZeneca to
     Avanir hereunder), owned or Controlled by AstraZeneca or its Affiliates at
     the Effective Date or during the Collaboration Term and introduced at its
     sole discretion to Avanir under the Research

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     Collaboration by AstraZeneca or its Affiliates and (b) IP Protection Rights
     pertaining to any of the foregoing.

1.5  "ASTRAZENECA IMPROVEMENTS" means all Results that constitute Improvements
     to the AstraZeneca Background Technologies.

1.6  "ASTRAZENECA PATENTS" means Patents with respect to AstraZeneca
     Improvements.

1.7  "ASTRAZENECA INFORMATION" has the meaning set forth in Section 14.1.2.

1.8  "ASTRAZENECA PRINCIPAL SCIENTIST" means the principal scientist designated
     by AstraZeneca to be responsible for all Research Collaboration activities
     undertaken by AstraZeneca and serving as the primary contact for Avanir on
     all matters related to the Research Collaboration. The AstraZeneca
     Principal Scientist is listed in Schedule 6 hereto.

1.9  "AVANIR PRINCIPAL SCIENTIST" has the meaning defined in Section 5.2.

1.10 "AVP 26452 COMPOUND" means Avanir's proprietary compound referred to as AVP
     26452 with the chemical structure set forth in item 1.3 of the Research
     Plan and any metabolites, salts, esters, free acid forms, free base forms,
     pro-drug forms, racemates and all optically active forms thereof.

1.11 "AVP 26452 PRODUCT" means products in final forms suitable for human,
     veterinary or agricultural use that contain the AVP 26452 Compound as the
     sole active ingredient.

1.12 "BACK-UP COMPOUND(S)" means any compound, other than the AVP 26452
     Compound, and any metabolites, salts, esters, free acid forms, free base
     forms, pro-drug forms, racemates and all optically active forms of such
     compound covered or claimed by the Licensed Patents.

1.13 "BACK-UP PRODUCT" means products in final forms suitable for human,
     veterinary or agricultural use that contain a Back-Up Compound as the sole
     active ingredient.

1.14 "BREACHING PARTY" has the meaning set forth in Section 21.5.

1.15 "CALENDAR QUARTER" means each successive period of three (3) calendar
     months commencing on 1st January, 1st April, 1st July and 1st October.

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1.16 "CALENDAR YEAR" means each successive period of twelve (12) calendar months
     commencing on 1st January.

1.17 "CANDIDATE DRUG" or "CD" means a Licensed Compound satisfying the relevant
     pharmacological and pharmaceutical criteria for clinical testing
     established by AstraZeneca at its sole discretion and selected by
     AstraZeneca in its sole discretion as a candidate for clinical development
     or, if not meeting such criteria, nevertheless is so selected by
     AstraZeneca.

1.18 "***" has the meaning defined in Section 11.1.2.

1.19 "***" has the meaning defined in Section 11.1.2.

1.20 "CARDIOVASCULAR EVENTS" means stroke, myocardial infarction and
     cardiovascular death.

1.21 "CHANGE OF CONTROL" with respect to any Person, means an event in which:

     1.21.1 any other Person or group of Persons not then beneficially owning
          more than fifty percent (50%) of the voting power of the outstanding
          securities of such Person acquires beneficial ownership of securities
          of such first Person representing more than fifty percent (50%) of the
          voting power of the then outstanding securities of such first Person
          with respect to the election of directors of such first Person; or

     1.21.2 such Person enters into a merger, consolidation or similar
          transaction with another Person and the holders of such first Person
          do not hold a majority in interest of the voting securities of such
          surviving entity immediately following such transaction.

1.22 "COLLABORATION COMPOUND" means any Hit, Lead or other compound, other than
     the AVP 26452 Compound or the Back-Up Compounds, discovered, identified or
     otherwise selected by AstraZeneca or the Parties jointly as a direct result
     of Hit Optimisation or Lead Optimisation and any metabolites, prodrugs,
     racemates, isomers, enantiomers, salts,

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     Company's Application Requesting Confidential Treatment under Rule 24b-2
     under the 1934 Act.

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     esters and free acid forms of any of the foregoing, for which compound the
     first application for a Joint Patent or an AstraZeneca Patent containing a
     Valid Claim claiming the compound as a composition of matter is made
     anywhere in the world within *** years from the expiration or termination
     of the Collaboration Term.

1.23 "COLLABORATION PRODUCT" means products in final forms suitable for human,
     veterinary or agricultural use that contain a Collaboration Compound as the
     sole active ingredient.

1.24 "COLLABORATION MATERIALS" means any compounds, cells, cell lines, DNA and
     RNA molecules, plasmids, proteins, crystals, coordinates, antibodies,
     antibody coding DNA sequences, antibody coding expression vectors and
     antibody expressing transfected cell lines and other materials and any
     replications of any of the foregoing, that one Party provides to the other
     Party to enable such Party to perform work under the Research
     Collaboration; provided, however, that "Collaboration Materials" shall
     exclude all Collaboration Results.

1.25 "COLLABORATION RESULTS" means Results that are discovered, conceived,
     reduced to practice or otherwise generated through work performed under the
     Research Collaboration, provided, however, that Collaboration Results shall
     exclude all AstraZeneca Improvements.

1.26 "COLLABORATION TERM" has the meaning set forth in Section 21.2.

1.27 "COLLABORATION YEAR" means the twelve-month period starting on the
     Effective Date and any immediately subsequent twelve-month period.

1.28 "COMBINATION PRODUCTS" means products in final forms suitable for human,
     veterinary or agricultural uses that contain a Licensed Compound as an
     active ingredient together with one or more other active ingredients that
     are sold either as a fixed dose or as separate doses in a single package.

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1.29 "COMMERCIALLY REASONABLE EFFORTS" means, with respect to the research,
     development, Manufacture or commercialisation of a Licensed Compound or
     Licensed Product, as the case may be, efforts and resources commonly used
     in the research-based pharmaceutical industry for compounds or products
     with similar commercial and scientific potential at a similar stage in
     their lifecycle, taking into consideration their safety and efficacy, their
     cost to develop, the competitiveness of alternative products, the
     anticipated or, if applicable, actual claim structure and the nature and
     extent of their market exclusivity (including Patent coverage and
     regulatory exclusivity), the likelihood of regulatory approval, their
     estimated profitability, including the amounts of marketing and promotional
     expenditures with respect to the Licensed Products and Competing Products
     and all other relevant factors. Commercially Reasonable Efforts shall be
     determined on a market-by-market basis for each Licensed Compound and each
     Licensed Product, as applicable; provided, however, that should what would
     otherwise constitute Commercially Reasonable Efforts with respect to an
     individual market conflict with, or otherwise not constitute, Commercially
     Reasonable Efforts with respect to a group of markets out of which such
     market is a part then Commercially Reasonable Efforts shall be determined
     for such group of markets as a whole.

1.30 "COMPETING PRODUCT" has the meaning set forth in Section 10.5.1 a).

1.31 "COMPLAINING PARTY" has the meaning set forth in Section 21.5.

1.32 "CONFIDENTIAL INFORMATION" has the meaning set forth in Section 14.1.1.

1.33 "CONTROL" means, with respect to any item of Information, Patent or IP
     Protection Right, possession of the right, whether directly or indirectly,
     and whether by ownership, licence or otherwise, to assign, or grant a
     licence, sublicence or other right to or under, such Information, Patent or
     IP Protection Right as provided for herein without violating the terms of
     any agreement or other arrangement with any Third Party.

1.34 "DEVELOPMENT PROJECT" means any activities hereunder by or on behalf of
     AstraZeneca or its Affiliates outside of the Research Collaboration with
     the aim of developing a Licensed Product.

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1.35 "DEVELOPMENT REPORT" has the meaning set forth in Section 8.4.

1.36 "DEVELOPMENT RESULTS" means any and all Results not constituting
     Collaboration Results or AstraZeneca Improvements.

1.37 "DISCLOSING PARTY" has the meaning set forth in Section 14.1.1.

1.38 "DISTRIBUTOR" has the meaning set forth in Section 3.4.

1.39 "EFFECTIVE DATE" has the meaning set forth in the preamble to this
     Agreement.

1.40 "EUROPE" means the European Economic Area as it may be constituted from
     time to time.

1.41 "EXPLOIT" means to make, have made, import, use, sell, or offer for sale,
     including to research, develop, register, modify, enhance, improve,
     Manufacture, have Manufactured, hold/keep (whether for disposal or
     otherwise), formulate, optimise, have used, export, transport, distribute,
     promote, market or have sold or otherwise dispose or offer to dispose of, a
     product or process.

1.42 "EXPLOITATION" means the act of Exploiting a product or process.

1.43 "FDA" means the United States Food and Drug Administration and any
     successor agency thereto.

1.44 "FIRST COMMERCIAL SALE" means the first sale for monetary value for use or
     consumption by a member of the general public of a Licensed Product in a
     country in the Territory after Health Registration Approval for the sale of
     such Licensed Product has been obtained in such country. For the avoidance
     of doubt, sales prior to ***, shall not be construed as a First Commercial
     Sale.

1.45 "FORCE MAJEURE" has the meaning set forth in Section 22.1.

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1.46 "FORCE MAJEURE PARTY" means a Party prevented or delayed in its performance
     under this Agreement by an event of Force Majeure.

1.47 "FTE" means the equivalent of one (1) researcher being at least a graduate
     or a similarly qualified employee of Avanir having the requisite skills to
     fulfil Avanir's obligations under this Agreement and devoting the
     equivalent hours of a full time employee. For purposes of this Agreement,
     "full time" shall mean *** hours per Calendar Year as determined in
     accordance with Avanir's regular project hour reporting system.

1.48 "FTE RATE" means the price of one (1) FTE per single Calendar Year. The FTE
     Rate shall be *** U.S. Dollars ($***). The FTE Rate reflects the fully
     burdened costs for an FTE. AstraZeneca shall not be responsible for any
     Avanir ***, including *** costs, incurred in pursuit of the Research
     Collaboration and the consultation services rendered by Avanir under this
     Agreement, above and beyond the FTE Rate, or for ***.

1.49 "GRANT-BACK PATENTS" shall have the meaning set forth in Section 21.7.3.

1.50 "HEALTH AUTHORITY" means any applicable supra-national, federal, national,
     regional, state, provincial or local regulatory agency, department, bureau,
     commission, council or other government entity regulating or otherwise
     exercising authority with respect to the Exploitation of Licensed Compounds
     or Licensed Products in the Territory.

1.51 "HEALTH REGISTRATION APPROVAL" means, with respect to a country in the
     Territory, any and all approvals, licences, registrations or authorisations
     of any Health Authority necessary to commercially distribute, sell or
     market a Licensed Product in such country, including, where reasonably
     required to engage in such activities, (a) pricing or reimbursement
     approval in such country, (b) pre- and post-approval marketing
     authorisations (including any prerequisite Manufacturing approval or
     authorisation related thereto), (c) labelling approval and (d) technical,
     medical and scientific licences.

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1.52 "HIT" means any compound identified under the Research Collaboration and
     selected by the RCMC or by AstraZeneca, as applicable, as a candidate for
     Hit Optimisation.

1.53 "HIT OPTIMISATION" means chemical structure modification performed as part
     of the Research Collaboration or by or on behalf of AstraZeneca, as
     applicable, starting from a Hit and aiming at the identification of
     compounds with properties meeting the Lead criteria defined in the Research
     Plan.

1.54 "IF" has the meaning set forth in Section 6.3.2.

1.55 "IMPROVEMENTS" means any improvements, adaptations, modifications or
     upgrading, and any IP Protection Rights related thereto.

1.56 "IND" means an investigational new drug application filed with the FDA for
     authorisation to commence human clinical trials in the U.S., and its
     equivalent in other countries or regulatory jurisdictions in the Territory.

1.57 "INDEMNIFICATION CLAIM NOTICE" has the meaning set forth in Section 17.3.

1.58 "INDEMNIFIED PARTY" means a Party seeking to recover a Loss under Section
     17.1 or 17.2.

1.59 "INDEMNIFYING PARTY" means a Party from whom recovery of a Loss is sought
     under Section 17.1 or 17.2.

1.60 "INDEMNITEE" has the meaning set forth in Section 17.3.

1.61 "INDIRECT TAXES" means value added taxes, sales taxes, consumption taxes
     and other similar taxes.

1.62 "INFORMATION" means all technical, scientific and other know-how and
     information, trade secrets, knowledge, technology, means, methods,
     processes, practices, formulae, instructions, skills, techniques,
     procedures, experiences, ideas, technical assistance, designs, drawings,
     assembly procedures, computer programs, apparatuses, specifications, data,
     results and other material, including: the process and results of
     high-throughput screening, gene expression, genomics, proteomics and other
     drug discovery and development technology; biological, chemical,
     pharmacological, toxicological,

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     pharmaceutical, physical and analytical, pre-clinical, clinical, safety,
     manufacturing and quality control data and information, including study
     designs and protocols; assays and biological methodology; Manufacturing and
     quality control procedures and data, including test procedures; and
     synthesis, purification and isolation techniques, (whether or not
     confidential, proprietary, patented or patentable) in written, electronic
     or any other form now known or hereafter developed, but excluding the
     Regulatory Documentation.

1.63 "INFRINGEMENT SUIT" has the meaning set forth in Section 20.3.

1.64 "IP" has the meaning set forth in Section 21.10.

1.65 "IP PROTECTION RIGHTS" means any and all legal means of establishing rights
     in and to ideas, inventions, discoveries, know-how, data, databases,
     documentation, reports, materials, writings, designs, computer software,
     processes, principles, methods, techniques and other information, including
     Patents, trade marks, service marks, trade names, registered designs,
     design rights, copyrights (including rights in computer software and
     database rights) and any rights or property similar to any of the foregoing
     in any part of the world, whether registered or not, together with the
     right to apply for the registration of any such rights.

1.66 "JOINT EXECUTIVE COMMITTEE" or "JEC" means the joint committee established
     by the Parties pursuant to Article 6.2.1.

1.67 "JOINT PATENTS" means Patents with respect to Collaboration Results.

1.68 "KEY PERSONNEL" has the meaning set forth in Section 5.2.

1.69 "KNOWLEDGE" means a Party's and its Affiliates' understanding in good faith
     of the relevant facts and information resulting from the reasonable conduct
     of its business affairs, but without the requirement of performing an
     investigation with respect to any such facts and information.

1.70 "LEAD COMPOUND" or "LEAD" means a compound identified through Hit
     Optimisation under the Research Collaboration or by AstraZeneca, as
     applicable, that has been selected by the RCMC or AstraZeneca, whichever is
     applicable, as a candidate for Lead Optimisation.

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1.71 "LEAD OPTIMISATION" means chemical structure modification performed under
     the Research Collaboration or by or on behalf of AstraZeneca, whichever is
     applicable, starting from a Lead Compound and aiming at the identification
     of compounds with properties meeting the relevant CD criteria established
     by AstraZeneca at its sole discretion.

1.72 "LICENSED COMPOUNDS" means the AVP 26452 Compound, Back-Up Compound(s) and
     Collaboration Compounds.

1.73 "LICENSED IMPROVEMENT" means, subject to the limitations set forth in the
     next succeeding paragraph, any Improvement with respect to a Licensed
     Compound or Licensed Product or relating to the Exploitation thereof
     Controlled by Avanir or its Affiliates, not constituting a Development
     Result, whether or not patentable, that is conceived, reduced to practice,
     developed or discovered or otherwise made outside the Research
     Collaboration during the term of this Agreement by or on behalf of Avanir
     or its Affiliates or by the Parties or their respective Affiliates jointly,
     or their respective employees and agents (whether alone or jointly with
     others), or otherwise Controlled by Avanir or its Affiliates at any time
     prior to and at the Effective Date or during any period in which
     AstraZeneca owes royalties to Avanir pursuant to Section 10.2, and which
     AstraZeneca has not rejected pursuant to Section 12.4.1.

     An Improvement mentioned in the foregoing paragraph conceived, reduced to
     practice, developed or discovered, otherwise made or otherwise Controlled
     by or on behalf solely of Avanir or its Affiliates shall be deemed a
     Licensed Improvement only to the extent it relates to the Licensed Patents
     and to the extent such Improvement conceived, reduced to practice,
     developed or discovered or otherwise made by or on behalf of Avanir or its
     Affiliates, and not with AstraZeneca or its Affiliates, has application
     outside such area it may be utilised by Avanir for any purpose other than
     to (a) conduct any activity with, for the benefit of, or sponsored by, any
     Person, that has as its goal or intent discovering,

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     identifying, Exploiting or otherwise commercialising products within *** or
     their associated mechanisms, or (b) grant any licence or other rights to
     any Person to utilise any IP Protection Rights Controlled by Avanir or its
     Affiliates (including, for the avoidance of doubt, any Licensed Patents,
     Licensed Know-How, Joint Patents or Collaboration Results) for the purpose
     of discovering, identifying, Exploiting or otherwise commercialising
     products within *** or their associated mechanisms.

1.74 "LICENSED KNOW-HOW" means the Information set out and described in Schedule
     2, which is in the Control of Avanir or its Affiliates as of the Effective
     Date, being Information that is not generally known and is necessary or
     useful for the Exploitation of the Licensed Compounds or the Licensed
     Products, including any Information with respect to Licensed Improvements,
     as mentioned in Section 12.4.1, but excluding any Information to the extent
     covered or claimed by the Licensed Patents.

1.75 "LICENSED PATENTS" means (a) all patent applications and patents set forth
     in Schedule 4 hereto, (b) any Patents with respect to such patent
     applications or patents, and (c) any Patents claiming or covering any
     Licensed Improvements.

1.76 "LICENSED PRODUCTS" means the Products and the Combination Products.

1.77 "LOSSES" means any and all direct or indirect liability, damage, loss or
     expense, including interest, penalties and lawyers' fees and disbursements.
     In calculating Losses, the duty to mitigate on the part of the Party
     suffering the Loss shall be taken into account.

1.78 "MAJOR MARKET" means (a) ***, (b) ***, or (c) ***.

1.79 "MANUFACTURE" and "MANUFACTURING" means, with respect to a product or
     compound, the synthesis, manufacturing, processing, formulating, packaging,
     labelling, holding and quality control testing of such product or compound.

1.80 "NET SALES" means the gross invoiced amount on sales of the Licensed
     Products by AstraZeneca and its Affiliates to Third Parties (including
     Distributors) after deduction of:

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          (a)  normal and customary trade, quantity or prompt settlement
               discounts (including chargebacks and allowances) actually
               allowed;

          (b)  amounts *** or *** by reason of *** determined by AstraZeneca or
               its Affiliates in good faith and pursuant to standard industry
               practice;

          (c)  *** and similar payments made with respect to *** such as, by way
               of illustration and not in limitation of the Parties' rights
               hereunder, ***;

          (d)  ***; and

          (e)  any other similar deductions that are actually credited to the
               customer and are consistent with generally accepted accounting
               principles, or in the case of non-United States sales, other
               applicable accounting standards; and

          (f)  as an allowance for ***, *** percent (***%) of the amount arrived
               at after the application of the provisions of items (a) to (e)
               above.

     Net Sales shall be calculated using AstraZeneca's internal, externally
     audited, systems used to report such sales, which reporting is done in
     accordance with International Accounting Standards (IAS) consistently
     applied, as adjusted for any of items (a) to (f) above not taken into
     account in such systems.

1.81 "NOTICE PERIOD" has the meaning set forth in Section 21.5.

1.82 "OTHER INDICATION" means a medical indication, other than (i) ***; or (ii)
     ***.

1.83 "PARTY" means either AstraZeneca or Avanir and "Parties" means both
     AstraZeneca and Avanir.

1.84 "PATENTS" means (a) all national, regional and international patents and
     patent applications, including provisional patent applications, (b) all
     patent applications filed

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     either from such patents, patent applications or provisional applications
     or from an application claiming priority from either of these, including
     divisionals, continuations, continuations-in-part, provisionals, converted
     provisionals, and continued prosecution applications, (c) any and all
     patents that have issued or in the future issue from the foregoing patent
     applications ((a) and (b)), including utility models, petty patents and
     design patents and certificates of invention, (d) any and all extensions or
     restorations by existing or future extension or restoration mechanisms,
     including revalidations, reissues, re-examinations and extensions
     (including any supplementary protection certificates and the like) of the
     foregoing patents or patent applications ((a), (b) and (c)), and (e) any
     similar rights, including so-called pipeline protection, or any
     importation, revalidation, confirmation or introduction patent or
     registration patent or patent of additions to any such foregoing patent
     applications and patents.

1.85 "PAYMENTS" has the meaning set forth in Section 10.15.1.

1.86 "PERSON" means a sole proprietorship, partnership, limited partnership,
     limited liability partnership, corporation, limited liability company,
     business trust, joint stock company, trust, unincorporated association,
     joint venture or other similar entity or organisation, including a
     government or political subdivision, department or agency of a government,
     or an individual.

1.87 "PHASE II CLINICAL TRIAL" means either a) a clinical trial performed in
     patients with the primary objective of establishing proof of concept,
     assessing safety and tolerability or demonstration of a pharmacological
     effect of a Licensed Product, or b) a clinical study performed in patients
     to assess safety, tolerability and efficacy for the purpose of identifying
     suitable doses for a Phase III Clinical Trial.

1.88 "PHASE III CLINICAL TRIAL" means a large scale, multi-centre, human
     clinical trial (excluding dose ranging studies) to be conducted in a number
     of patients estimated to be sufficient to primarily establish efficacy of a
     Licensed Product in the claim of e.g. dyslipidemia or antiatherosclerosis
     or any other claimed major medical indication and at a standard suitable to
     obtain a Health Registration Approval in a Major Market.

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1.89 "PRODUCTS" means the AVP 26452 Product, Back-Up Products and Collaboration
     Products.

1.90 "RCMC" has the meaning defined in Section 6.1.1.

1.91 "RECEIVING PARTY" has the meaning set forth in Section 14.1.1.

1.92 "REGULATORY DOCUMENTATION" means all applications, registrations, licences,
     authorisations and approvals (including all Health Registration Approvals),
     all correspondence submitted to or received from Health Authorities
     (including minutes and official contact reports relating to any
     communications with any Health Authority) and all supporting documents and
     all clinical studies and tests, relating to any Licensed Compounds or
     Licensed Products, and all data contained in any of the foregoing,
     including all IND applications, Health Registration Approvals, regulatory
     drug lists, advertising and promotion documents, adverse event files and
     complaint files.

1.93 "RESEARCH COLLABORATION" means the research collaboration outlined in the
     Research Plan to be carried out during the Collaboration Term; provided,
     however, that with respect to each individual Licensed Compound the
     Research Collaboration shall cease on the date of AstraZeneca's selection
     of such Licensed Compound as a Candidate Drug. For the avoidance of doubt,
     (i) any research or development concerning the Licensed Compounds or the
     Licensed Products beyond the Research Collaboration will be part of the
     Development Project, and (ii) notwithstanding the fact that the Research
     Collaboration may have ceased with respect to one or more Licensed
     Compounds the Research Collaboration shall, unless terminated earlier in
     accordance with the terms and conditions of this Agreement, continue for
     the duration of the Collaboration Term.

1.94 "RESEARCH PLAN" means the research plan attached hereto as Schedule 1
     outlining the Research Collaboration and each Party's undertakings and
     obligations, including the allocation of Key Personnel and other FTEs by
     Avanir, in relation thereto as may be amended from time to time in
     accordance with Section 6.1.2.

1.95 "RESULTS" means ideas, inventions, discoveries, know-how, data,
     documentation, reports, materials, writings, designs, computer software,
     processes, principles, methods,

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     techniques and other information, recorded in any form, that are
     discovered, conceived, reduced to practice or otherwise generated through
     work performed under this Agreement by or on behalf of either Party or by
     the Parties jointly, and any IP Protection Rights pertaining to any of the
     foregoing.

1.96 "***" has the meaning defined in Section 11.1.1.

1.97 "***" has the meaning defined in Section 11.1.3.

1.98 "SUBLICENSEE" has the meaning set out in Section 3.3.

1.99 "SUCCESSFUL PROOF OF CONCEPT" means agreement of the Parties in writing
     that there exists evidence of an effect (whether a clinical outcome or
     other bio marker) indicating a high chance of achieving a result of a Phase
     III Clinical Trial in an indication in which the Licensed Product concerned
     could be expected to generate peak Annual Net Sales of at least *** U.S.
     Dollars ($***), or initiation of the next step of clinical assessment by
     AstraZeneca after having discovered such effect.

1.100 "SURROGATE MARKER" means a marker accepted by the Health Authority in a
     Major Market as a substitute for showing a reduction of the risk of ***.

1.101 "TERRITORY" means all countries in the world, except for those countries
     in which this Agreement is terminated pursuant to Sections 21.3, 21.4 or
     21.5.

1.102 "THIRD PARTY" means any Person not including the Parties, the Parties'
     respective Affiliates or Sublicensees.

1.103 "THIRD PARTY CLAIM" has the meaning set forth in Section 17.1.

1.104 "TRADEMARK" means any word, name, symbol, colour, designation or device or
     any combination thereof, including any trademark, trade dress, brand mark,
     trade name, brand name, logo or business symbol used by AstraZeneca in
     connection with the Licensed Compounds or Licensed Products.

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1.105 "TRIGGERING EVENT" has the meaning set forth in Section 20.1.

1.106 "UNITED STATES" or "U.S." means the United States of America, including
     its territories, possessions and Puerto Rico.

1.107 "VALID CLAIM" shall mean, with respect to a Licensed Product in a
     particular country, any claim of a Licensed Patent, a Joint Patent or an
     AstraZeneca Patent that claims (i) the Licensed Compound included in such
     Licensed Product as a composition of matter; (ii) the formulation of such
     Licensed Product or (iii) a method related to, or a use of, the Licensed
     Compound or Licensed Product; provided such claims were filed
     contemporaneously with, or after, the claims described in clause (i) above;
     and provided, further, that a claim described in either clause (ii) or
     clause (iii) above could be reasonably considered to be the reason that
     generic competition (as defined in Section 10.5.1 (a)) has not occurred, as
     determined on a country-by-country basis, and either:

          (a)  with respect to a granted and unexpired Licensed Patent, Joint
               Patent or AstraZeneca Patent in such country, (i) has not been
               held permanently revoked, unenforceable or invalid by a decision
               of a court or other governmental agency of competent
               jurisdiction, which decision is unappealable or unappealed within
               the time allowed for appeal, and (ii) has not been abandoned,
               disclaimed, denied or admitted to be invalid or unenforceable
               through reissue or disclaimer or otherwise; or

          (b)  with respect to a pending Licensed Patent, Joint Patent or
               AstraZeneca Patent application, was filed and is being prosecuted
               in good faith and has not been abandoned or finally disallowed
               without the possibility of appeal or re-filing of the
               application, provided that such claim has not been pending for
               more than *** years.

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2    CONSTRUCTION

     Except where the context requires otherwise, whenever used the singular
     includes the plural, the plural includes the singular, the use of any
     gender is applicable to all genders and the word "or" has the inclusive
     meaning represented by the phrase "and/or". Whenever this Agreement refers
     to a number of days, unless otherwise specified, such number refers to
     calendar days. The headings of this Agreement are for convenience of
     reference only and do not define, describe, extend or limit the scope or
     intent of this Agreement or the scope or intent of any provision contained
     in this Agreement. The term "including" or "includes" as used in this
     Agreement means including, without limiting the generality of any
     description preceding such term. The wording of this Agreement shall be
     deemed to be the wording mutually chosen by the Parties and no rule of
     strict construction shall be applied against any Party.

3    GRANT OF RIGHTS

3.1  Licence Grants to AstraZeneca. Subject to the terms and conditions of this
     Agreement, Avanir hereby grants to AstraZeneca an exclusive (including with
     regard to Avanir and its Affiliates), subject to a retained right thereto
     for the sole purpose of Avanir carrying out its obligations under the
     Research Collaboration, right and licence in the Territory, with the right
     to grant sublicenses pursuant to Section 3.3, under Avanir's and its
     Affiliates' rights, titles, and interests in and to the Licensed Patents,
     the Licensed Know-How, the Collaboration Results, the Joint Patents and the
     Licensed Improvements to (i) Exploit the Licensed Compounds and the
     Licensed Products for all purposes and (ii) use and otherwise Exploit the
     Licensed Know-How and the Collaboration Results in connection with the
     purposes set forth in clause (i) immediately preceding.

3.2  Licence Grants to Avanir. AstraZeneca hereby grants to Avanir a
     non-exclusive right and licence, without the right to grant sublicenses,
     under AstraZeneca's rights, titles, and interests in and to the AstraZeneca
     Background Technologies, the AstraZeneca Improvements, the AstraZeneca
     Patents, the Joint Patents and the Collaboration Results that are disclosed
     or otherwise provided by AstraZeneca to, or discovered by, Avanir during
     the Collaboration Term (a) solely to the extent required by Avanir to
     perform the

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     Research Collaboration during the Collaboration Term, and (b) to use and
     otherwise Exploit such AstraZeneca Background Technologies and AstraZeneca
     Improvements as necessary or useful to exercise Avanir's rights under the
     grant under (a).

3.3  Sublicenses. AstraZeneca shall, subject to Section 10.4, have the right to
     grant sublicenses, through multiple tiers of sublicensees, under the
     licences granted in Section 3.1, to its Affiliates and to any other Persons
     in the Territory or in any country of the Territory. Where AstraZeneca
     grants a sublicense to a Person that is not an Affiliate of AstraZeneca,
     and such Person is not a Distributor, such Person shall be a "SUBLICENSEE"
     for purposes of this Agreement. AstraZeneca shall ensure that all Persons
     to which it grants sublicenses will comply with all terms and conditions of
     this Agreement and AstraZeneca shall remain liable for any breach of this
     Agreement by a Sublicensee. AstraZeneca shall provide notice of the
     granting of any sublicence hereunder promptly following the making of such
     grant. Such notice shall identify the Sublicensee, the territory of the
     sublicence and a copy of those provisions of the sublicense that relate to
     performance of this Agreement.

3.4  Distributorships. AstraZeneca shall have the right, in its sole discretion,
     to appoint its Affiliates, and AstraZeneca and its Affiliates shall have
     the right, in their sole discretion, to appoint any other Persons, in the
     Territory or in any country of the Territory, to distribute, market and
     sell the Licensed Products (with or without packaging rights), in
     circumstances where the Person purchases its requirements of Licensed
     Products from AstraZeneca or its Affiliates but does not otherwise make any
     royalty or other payment to AstraZeneca with respect to its IP Protection
     Rights. Where AstraZeneca or its Affiliates appoints such a Person that is
     not an Affiliate of AstraZeneca, that Person shall be a "DISTRIBUTOR" for
     purposes of this Agreement. The term "packaging rights" in this Section 3.4
     shall mean the right for the Distributor to package Licensed Products
     supplied in unpackaged bulk form into individual ready-for-sale packs.

3.5  Co-Promotion Rights. For the avoidance of doubt, AstraZeneca and its
     Affiliates shall have the right, in their sole discretion, to co-promote
     the Licensed Products with any

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     other Person, or to appoint one or more Third Parties to promote the
     Licensed Products without AstraZeneca carrying out any promotion in all or
     any part of the Territory.

3.6  Commercially Viable Use of Avanir's Sales Force. In anticipation of the
     Health Registration Approval of the initial Licensed Product in the United
     States, AstraZeneca and Avanir shall meet and confer to establish the terms
     and conditions, beyond those set forth herein, upon which AstraZeneca will,
     should AstraZeneca determine in its then current sales and marketing plan a
     need to have the Licensed Product concerned promoted among *** in second or
     third-line promotional activities, use Avanir's sales force to support
     AstraZeneca's sales efforts in the United States in respect of such initial
     Licensed Product by way of second or third line promotional activities in
     the segment of ***. Such right of Avanir shall always be subject to the
     provisos that (i) each member of Avanir's sales force intended to support
     AstraZeneca as described hereunder meets the then applicable AstraZeneca
     standard quality criteria for sales representatives; (ii) such Avanir
     personnel shall be deployed only pursuant to the relevant sales and
     marketing plan by AstraZeneca for the initial Licensed Product; (iii)
     AstraZeneca's obligation to compensate Avanir for such services be limited
     to ***; and (iv) that such detail calls by Avanir shall not in any given
     calendar quarter exceed *** percent (***%) of the aggregate detail calls
     with specialists by AstraZeneca's or its Affiliates' sales forces for the
     initial Licensed Product in such calendar quarter. Notwithstanding the
     foregoing to the contrary, in the event that AstraZeneca decides to
     outsource sales or promotional activities pertaining to the Licensed
     Product in the neuro-specialist field in the U.S. beyond the activities of
     Avanir pursuant to this Section 3.6, AstraZeneca shall meet and confer with
     Avanir on such subject for the purpose of providing Avanir an opportunity
     to seek such business if it so desires.

3.7  No Conflicts.

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     3.7.1 Within the scope of the Research Collaboration, and to the extent
          Applicable Law permits Avanir to conduct research and development
          activities with respect to Licensed Compounds or Licensed Products
          notwithstanding the exclusive licence grants to AstraZeneca under
          Section 3.1, Avanir agrees that neither it nor its Affiliates will
          publish or present any material or file any Patent applications with
          respect to such activities without the consent of AstraZeneca.

     3.7.2 Subject to Avanir's rights and obligations under the Research
          Collaboration, and during the Collaboration Term and for *** years
          after its termination or expiration, or, if this Agreement is
          terminated by AstraZeneca pursuant to Section 21.5, for a period of
          *** year after such termination, Avanir covenants that it and its
          majority-owned subsidiaries (and its other Affiliates which are
          Affiliates both as of the Effective Date and during the periods
          referred to above) shall not, and that it shall use its best
          reasonable efforts to cause its Affiliates other than those mentioned
          above not to, (a) conduct any activity with, for the benefit of, or
          sponsored by, any Person, that has as its goal or intent discovering,
          identifying, Exploiting or otherwise commercialising *** or their
          associated mechanisms, or (b) grant any licence or other rights to any
          Person to utilise any IP Protection Rights Controlled by Avanir or its
          majority-owned subsidiaries (or its other Affiliates which are
          Affiliates both as of the Effective Date and during the period
          referred to above), or by such Affiliates of Avanir other than those
          referred to above to the extent Avanir has the ability to prevent such
          grant provided always that Avanir uses its best reasonable efforts in
          this regard, (including, for the avoidance of doubt, any Licensed
          Patents, Licensed Know-How, Joint Patents or Collaboration Results)
          for the express purpose of discovering, identifying, Exploiting or
          otherwise commercialising *** or their associated mechanisms. Avanir
          agrees that it will not create Affiliates after the Effective Date for
          the

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          purpose of obviating compliance with this Section 3.7.2. The Parties
          acknowledge that all restrictions contained in this Section 3.7.2 are
          reasonable, valid and necessary for the adequate protection of the
          Licensed Product business and because of the disclosure of
          Confidential Information by AstraZeneca, and that AstraZeneca would
          not have entered into this Agreement without the protection afforded
          it by this Section 3.7.2.

3.8  Exclusivity Term. AstraZeneca's exclusive position granted by Section 3.1
     shall expire with respect to each separate Licensed Product, on a
     country-by-country basis, on the date when AstraZeneca's obligation to pay
     royalties with respect to such Licensed Product pursuant to Section 10.2 or
     Section 10.4, as applicable, expires. Upon expiration of the royalty term
     set forth in Section 10.8 with respect to a Licensed Product in a country,
     AstraZeneca's licence with respect to such Licensed Product in such country
     shall become non-exclusive, fully paid-up, perpetual and irrevocable and
     the Net Sales of such Licensed Product in such country shall be excluded
     from the royalty calculations in Sections 10.2 (including the thresholds
     and ceilings) or 10.4, as applicable. AstraZeneca and its Affiliates and
     Sublicensees following such expiration shall be allowed to continue
     Exploiting such Licensed Product and using all Licensed Know-How and
     Collaboration Results in connection therewith on a non-exclusive basis in
     such country with no further consideration to Avanir.

3.9  Regulatory Documentation. The Parties acknowledge that Avanir will prepare
     in conjunction with AstraZeneca and submit the first IND application
     concerning the AVP 26452 Compound in accordance with the IND filing plan
     attached hereto as Schedule 3. Furthermore, in the event that in response
     to the submission of the IND, the Regulatory Authority poses questions to
     Avanir or otherwise requires additional data, Avanir and AstraZeneca shall
     cooperate to meet and confer as required to formulate an action plan in
     response to such request. It is acknowledged that AstraZeneca may ask
     Avanir to manage the single and multiple ascending dose studies associated
     with the IND filing and

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     Avanir agrees (at AstraZeneca's request) to make up to *** FTEs available
     to manage such studies. AstraZeneca shall reimburse Avanir for the work of
     such FTEs at the FTE rate. AstraZeneca may from time to time during the
     term of this Agreement reasonably request Avanir to make, at AstraZeneca's
     cost, applications for an IND in addition to that mentioned above in this
     Section 3.9 or other regulatory approvals whether in Avanir's or in
     AstraZeneca's or any of its Affiliates' name and Avanir undertakes to
     comply with any such reasonable request. Without exception, AstraZeneca
     will, as between AstraZeneca and Avanir, be the owner of any Regulatory
     Documentation relating to any such applications for an IND or regulatory
     approvals as mentioned in this Section 3.9 (including IND applications and
     approvals).

     Notwithstanding what is stated above in this Section 3.9 should the first
     IND Application either (a) not have been submitted by ***, or (b) not have
     become effective within *** of submission, AstraZeneca shall have the
     right, in its sole discretion, upon written notice to Avanir either to
     require Avanir to transfer such IND Application to it or to instruct Avanir
     in the conduct of remedial measures to allow such IND Application to be
     submitted and to become effective, as the case may be. Upon transfer of
     such IND Application, AstraZeneca shall be responsible for preparing and
     submitting such IND Application.

4    CONFIRMATORY PATENT LICENCES

     Avanir shall if requested to do so by AstraZeneca promptly enter into
     confirmatory licence agreements in the form or substantially the form set
     out in Schedule 5 for purposes of recording the licences granted under this
     Agreement with such Patent Offices in the Territory as AstraZeneca
     considers appropriate. Until the execution of any such confirmatory
     licences, so far as may be legally possible, Avanir and AstraZeneca shall
     have the same rights in respect of the Licensed Patents and the Joint
     Patens and be under

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     the same obligations to each other in all respects as if the said
     confirmatory licences had been executed.

5    THE RESEARCH COLLABORATION

5.1  Conduct of Research Collaboration. During the Collaboration Term and under
     the direction and supervision of the RCMC, each Party shall (a) perform or
     cause to be performed its obligations under the Research Plan in good
     scientific manner and in compliance in all material aspects with all
     Applicable Law, including, unless otherwise set forth in the Research Plan,
     good laboratory practices and good clinical practices, and (b) allocate the
     time, effort, equipment and skilled personnel to complete such activities
     as set forth in the Research Plan. Following the Effective Date, the
     Parties shall promptly commence the Research Collaboration. Avanir
     undertakes insofar as it relates to animal care in the activities to be
     carried out by it hereunder to comply with the AAALAC standards and shall
     use its best reasonable efforts to comply with the AstraZeneca
     International Policy on Animal Care and Use to the extent stricter than the
     AAALAC standards.

5.2  Facilities and Key Personnel. Avanir shall provide facilities, equipment
     and manpower that are reasonably necessary to carry out the work undertaken
     by Avanir under the Research Collaboration at Avanir's facilities at 11388
     Sorrento Valley Road, Suite 200, in San Diego, California, USA, and, after
     AstraZeneca's prior written approval, at such other facilities which Avanir
     may come to occupy of an appropriate standard for performing research in
     accordance with Good Laboratory Practice and otherwise in accordance with
     the Research Plan. Subject to Section 5.3, the foregoing undertaking shall
     not be construed to prevent Avanir from relying upon subcontractors for the
     performance of activities under the Research Plan which are, or would be,
     of a type typically performed by subcontractors. The principal scientist
     designated by Avanir (the "AVANIR PRINCIPAL SCIENTIST") shall be
     responsible for all Research Collaboration activities undertaken by Avanir
     and shall supervise the work of all personnel engaged by Avanir in the
     Research Collaboration. The Avanir Principal Scientist shall serve as the
     primary contact for AstraZeneca on all matters related to the Research
     Collaboration.

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     The Avanir Principal Scientist and other scientific and technical personnel
     of Avanir considered by AstraZeneca to be of key importance for the conduct
     of the Research Collaboration (the "KEY PERSONNEL") are listed on Schedule
     6 hereto. Avanir shall not substitute persons for the Key Personnel or
     materially reduce the time commitment of any Key Personnel to the Research
     Collaboration without the prior written approval of AstraZeneca, which
     approval with respect to the Key Personnel shall not be unreasonably
     withheld or notice whether approval is granted unreasonably delayed. In the
     event that any Key Personnel are no longer employed by Avanir or are
     otherwise incapable of performing their obligations under this Agreement
     (e.g., become disabled), the Parties shall meet and discuss in good faith
     how best to proceed provided, however, that in case the Principal Scientist
     terminates his employment with Avanir or leaves the employment for any
     other reason (including death) during the *** Collaboration Year, Avanir
     shall have a reasonable opportunity to find a replacement of comparable
     experience and stature satisfactory to AstraZeneca; provided, however, if
     Avanir is unable to hire a reasonably satisfactory replacement within ***
     days of the date the Principal Scientist terminates or leaves his
     employment, AstraZeneca shall have the right to terminate the Research
     Collaboration by providing *** days' written notice thereby ending the
     Collaboration Term. Upon such termination AstraZeneca shall be under no
     obligation to provide Avanir with any further compensation pursuant to
     Article 9 and the provisions of Section 21.6 (y) shall apply.

5.3  Subcontracting. Avanir shall be solely responsible for successfully
     completing its activities set forth in the Research Plan. Avanir shall
     conduct and carry out the activities provided for under the Research
     Collaboration primarily through its employees at the site identified under
     Section 5.2. Avanir, prior to engaging a subcontractor to carry out any
     significant portion of such activities shall seek the consent of
     AstraZeneca which shall not be unreasonably withheld or notice whether
     consent is provided unreasonably

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     delayed. Any subcontract shall be subject to the applicable terms and
     conditions of this Agreement, including Articles 14 and Section 16.1, and,
     upon AstraZeneca's request, Avanir shall require each such subcontractor to
     enter into an undertaking, pursuant to which the terms and conditions of
     this Agreement shall apply directly between such subcontractor and
     AstraZeneca, prior to disclosing to such subcontractor any of AstraZeneca's
     Confidential Information; provided, however, that Avanir shall remain
     ultimately responsible for the performance of its obligations under this
     Agreement. Any fees or costs due any such subcontractor shall be at the
     sole expense of Avanir.

5.4  Collaboration Materials and Information Transfer.

     5.4.1 Avanir shall, and shall cause its majority-owned subsidiaries and its
          other Affiliates (which are its Affiliates both as of the Effective
          Date and at all relevant times thereafter) and use its best reasonable
          efforts to cause its Affiliates other than those referred to above,
          without additional compensation and at Avanir's sole expense, provide
          to AstraZeneca copies of any Licensed Know-How which could be
          reasonably considered material to the Research Collaboration, not
          previously provided to AstraZeneca, promptly after the Effective Date.
          Upon AstraZeneca's request to Avanir, Avanir shall promptly provide to
          AstraZeneca any copies of additional Licensed Know-How and originals
          of Licensed Know-How in those cases where AstraZeneca has a need for
          the same in connection with the filing and prosecution of patents.

     5.4.2 During the Research Collaboration each Party shall, and shall cause
          its majority-owned subsidiaries and its other Affiliates (which are
          its Affiliates both as of the Effective Date and at all relevant times
          thereafter) and use its best reasonable efforts to cause its
          Affiliates other than those mentioned above, in accordance with the
          criteria and mechanisms established by the RCMC, disclose and make
          available to the other Party, in whatever form such Party may
          reasonably request all Collaboration Results promptly upon the earlier
          of the conception or reduction to practice, discovery, development or
          making of such Collaboration Results.

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     5.4.3 Each Party shall, and shall cause its majority-owned subsidiaries and
          its other Affiliates (which are its Affiliates both as of the
          Effective Date and at all relevant times thereafter) and use its best
          reasonable efforts to cause its Affiliates other than those referred
          to above, in accordance with the criteria and mechanisms established
          by the RCMC, disclose and make available to the other Party, in
          whatever form such Party may reasonably request all Collaboration
          Material promptly upon the Effective Date or upon the earlier of the
          conception or reduction to practice, discovery, development or making
          of such Collaboration Material; provided, however, that,
          notwithstanding the foregoing, AstraZeneca shall only be required to
          provide or disclose to Avanir such Collaboration Materials and other
          information as it determines, in its sole discretion, is reasonably
          necessary for Avanir to perform its activities under the Research
          Collaboration and AstraZeneca retains the right, in its reasonable
          discretion, to withdraw any such Collaboration Material information
          from the Research Collaboration upon written notice to Avanir.

5.5  Cooperation. Each Party shall cooperate with any and all reasonable
     requests for assistance from the other Party with respect to the activities
     under the Research Collaboration, including by making its employees,
     consultants and other scientific staff available upon reasonable notice
     during normal business hours at their respective places of employment to
     consult with such other Party on issues arising in connection with the
     Research Collaboration.

5.6  Regulatory Records. Avanir and AstraZeneca each shall maintain, or cause to
     be maintained, records of its respective activities under the Research
     Collaboration in sufficient detail and in good scientific manner
     appropriate for patent and regulatory purposes, which shall be complete and
     accurate and shall fully and properly reflect all work done and results
     achieved in the performance of its respective activities under the Research
     Collaboration, and which shall be retained by such Party for at least five
     (5) years after the termination of the Research Collaboration, or for such
     longer period as may be required by Applicable Law; provided always that
     before destroying any such

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     record upon expiration of such period Avanir shall offer AstraZeneca in
     writing to transfer such record to AstraZeneca and shall, should
     AstraZeneca declare that it wishes to have such record transferred,
     transfer it to AstraZeneca, at AstraZeneca's cost, without unreasonable
     delay. AstraZeneca shall preserve such records for the benefit of, and
     transfer to, Avanir in anticipation of a termination of this Agreement that
     could result in the transfer of such documents to Avanir. Each Party shall
     have the right, during normal business hours and upon reasonable notice, to
     inspect and copy any such records contemplated by this Section 5.6.

6    MANAGEMENT OF THE RESEARCH COLLABORATION

6.1  Research Collaboration Management Committee.

     6.1.1 Responsibilities of RCMC. The Research Collaboration Management
          Committee (the "RCMC") established by the Parties oversees the
          initiation, planning and performance of the activities under the
          Research Collaboration. In particular, the responsibilities of the
          RCMC shall include: (a) for the period following the first
          Collaboration Year, consider and propose to the JEC the number of FTEs
          at Avanir to be funded under the Collaboration Term by AstraZeneca as
          set forth in Section 9.1; (b) establishing reporting criteria and
          mechanisms for making Collaboration Results available to the other
          Party; (c) establishing criteria and mechanisms for disclosing and
          making available to the other Party Collaboration Materials; (d)
          establishing prioritisation criteria for specific components under the
          Research Collaboration, including setting proposed dates for
          experimental initiation and completion of each stage of the Research
          Collaboration; (e) determining within fifteen (15) days of the
          completion of each stage of the Research Collaboration pertaining to a
          specific Licensed Compound whether the completion thereof has been
          successful and deciding whether or not to continue the Research
          Collaboration into the next stage (i.e., making "stop/go decisions");
          (f) monitoring workflow, including experimental sample transfer,
          sample analysis and data quality control, data analysis and
          summarisation, software installation (access), training and
          maintenance; (g) monitoring of sample throughput, and

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          overall Research Collaboration progress; (h) to the extent permitted
          by the Research Plan, assigning tasks and responsibilities taking into
          account each Party's respective specific capabilities and expertise in
          order to avoid duplication and enhance efficiency and synergies; (i)
          monitoring timely execution of the Research Collaboration, including
          compliance with budgets and timelines; and (j) reviewing and approving
          any amendments to the Research Plan, which to the extent they place
          additional responsibilities on Avanir shall require the express
          written consent of Avanir.

     6.1.2 Research Plan. The Parties acknowledge and agree that the Research
          Plan attached hereto as of the Effective Date sets forth the goals and
          objectives of the Research Collaboration and the broad terms of the
          Parties' respective undertakings to achieve those goals and
          objectives, and the funding of FTEs provided for under Section 9.1
          represents AstraZeneca's total financial obligation for all services
          to be rendered and expenses to be incurred by or on behalf of Avanir
          as necessary to achieve the goals and objectives of the Research
          Collaboration. The Parties further acknowledge and agree that the
          Research Plan will be amended by the RCMC from time to time during the
          Collaboration Term for each stage of the Research Collaboration to
          identify and define the specific undertakings of the Parties required
          to implement the Research Collaboration.

     6.1.3 Formation of RCMC. The RCMC shall consist of six (6) members with the
          requisite experience and seniority to enable them to make decisions on
          behalf of the Parties with respect to the initiation, planning and
          performance of the activities of the Research Collaboration, with
          equal numbers appointed by the respective Party, which shall include
          the Avanir Principal Scientist and the AstraZeneca Principal Scientist
          acting as Co-Chairs. Each Party shall have the right to replace its
          respective RCMC representatives upon written notice to the other
          Party, provided that any such substitute representative shall have
          substantially the equivalent experience and seniority as the
          representative that such person replaces. Each Party shall be entitled
          to bring for an agenda item at a

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          meeting of the RCMC such minimum numbers of advisors, consultants and
          other visitors which such Party considers in good faith necessary or
          useful to such Party to protect its interest regarding the business to
          be dealt with under such agenda item. If such visitors are not
          employees of a Party, their attendance at the RCMC meeting shall be
          further conditioned upon agreement with the inviting Party over
          confidentiality and non-use obligations no less burdensome than set
          forth herein.

     6.1.4 Disputes. The RCMC shall endeavour to reach consensus on all matters
          brought before it with each Party having a single vote, irrespective
          of the number of representatives actually in attendance at a meeting;
          provided, however, that in the event the RCMC is unable to resolve an
          outstanding matter before it, such matter shall be resolved by the
          JEC.

          Should the RCMC not be able to reach consensus on what proposal to
          bring to the JEC concerning such matter referred to under Section
          6.1.1 (a), each Party may bring its respective proposal to the JEC
          which shall then consider the proposals and make a decision in
          accordance with Section 6.2.4. The matter shall be deemed brought to
          the attention of the JEC when the first Party's proposal has been
          submitted to the JEC.

     6.1.5 Meetings. The RCMC shall meet at least quarterly and more frequently
          when required. Regular quarterly meetings shall be scheduled on a
          recurring schedule to be established by the RCMC (e.g. the first
          Tuesday of January, April, July and October at 9:30 a.m. at the place
          of meeting, if held in person), or at such other mutually agreeable
          times no less than three (3) months in advance, except for the initial
          meeting of the RCMC, which shall be at a mutually agreeable time and
          place. Any such regular meeting falling on a holiday when commercial
          banks are closed in any of Great Britain, Sweden or the United States
          shall be postponed until the next succeeding day when commercial banks
          are open for business in all three jurisdictions. The meetings shall
          be held by means of teleconference or videoconference or, when held in
          person, at AstraZeneca AB's facilities in Molndal, Sweden, or at other
          locations *** mutually

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          agreed upon by the Parties. Subject to what is stated in Section
          6.1.6, a quorum of the RCMC shall exist whenever there is present at a
          meeting each of the Co-Chairs or their respective designees. In
          addition, the RCMC may act without a formal meeting by a written
          memorandum signed by the Co-Chairs of the RCMC. Whenever any action by
          the RCMC is required hereunder during a time period in which the RCMC
          is not scheduled to meet, either Co-Chair shall have the right to call
          a special meeting or the Co-Chairs may cause the RCMC to take the
          action without a meeting in the applicable time period. Any such
          additional meetings shall be held at places and on dates selected by
          the Co-Chairs.

     6.1.6 Quorum. Notwithstanding what is stated in Section 6.1.5, the Co-Chair
          of AstraZeneca may call for a meeting to be held on a business day
          when commercial banks are open for business in Great Britain, Sweden
          and the United States by notifying Avanir no later than thirty (30)
          days in advance of a meeting of the RCMC of the exact date, time and
          location for the meeting. Provided that (i) such notice has been
          timely issued and that the meeting is held on the date, time and place
          so indicated, or (ii) that Avanir confirms that it has been properly
          notified about the meeting, quorum shall be considered constituted at
          that meeting unless all members of one Party fail to attend the
          meeting because of illness, where no substitution could be reasonably
          arranged, breakdown in general communications, travel difficulties
          beyond the reasonable control of such Party, or by other similar
          reasons. No meeting shall be called for a day on which the commercial
          banks are closed in any of Great Britain, Sweden or the United States.
          For the purpose of agreeing that Avanir has been properly notified of
          the meeting in the case under (ii), attendance to a meeting without
          express objection thereto shall be sufficient.

     6.1.7 Expenses. Avanir and AstraZeneca each shall bear all expenses of its
          RCMC members related to such members' participation on the RCMC and
          attendance at RCMC meetings.

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     6.1.8 Minutes. The RCMC shall keep accurate minutes of its deliberations,
          which minutes shall record all proposed decisions and all actions
          recommended or taken, all proposals to the JEC on the number of FTEs
          at Avanir to be funded by AstraZeneca in a subsequent Collaboration
          Year in accordance with Section 9.1, Research Collaboration progress
          reports provided to the RCMC pursuant to Section 7.1 and Collaboration
          Results generated of interest in the Research Collaboration.
          Furthermore, all CDs and pre-CDs selected by AstraZeneca during the
          Collaboration Term shall be recorded in the minutes of the RCMC.
          Drafts of minutes shall be delivered to the Co-Chairs of the RCMC
          within twenty (20) days after the respective meeting. The Parties, on
          an alternating basis, shall prepare and circulate the draft minutes.
          Draft minutes shall be edited by the Co-Chairs and shall be issued in
          final form only with the approval and agreement of the Co-Chairs, such
          issuance not subject to final determination by the JEC in the event of
          a dispute.

6.2  Joint Executive Committee.

     6.2.1 Formation of the JEC. The Parties shall establish a Joint Executive
          Committee (the "JEC") to resolve any outstanding matter before the
          RCMC that the RCMC is unable to resolve. The JEC shall consist of four
          (4) members with equal numbers appointed by each Party with the
          requisite experience and seniority to enable them to resolve any
          matter brought before them and make any necessary decisions on behalf
          of the Parties with respect to any such matter. Furthermore, the JEC
          shall include a Co-Chair to be designated by each Party. Each Party
          shall have the right to replace its respective JEC representatives
          upon written notice to the other Party, provided that any such
          substitute representative shall have substantially the equivalent
          experience and seniority as the representative that such person
          replaces.

     6.2.2 Meetings. The JEC shall meet within fifteen (15) days from when a
          matter in dispute is first brought to the attention of the JEC by the
          RCMC and when otherwise required for the purpose of the Research
          Collaboration. The meetings

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          shall be held by means of teleconference or videoconference or, when
          held in person, at AstraZeneca AB's facilities in Molndal, Sweden, or
          at other locations *** mutually agreed upon by the Parties. Subject to
          what is stated in Section 6.2.3, a quorum of the JEC shall exist
          whenever there is present at a meeting each of the Co-Chairs or their
          respective designees. The JEC shall endeavour to reach consensus on
          all matters brought before it with each Party having a single vote,
          irrespective of the number of representatives actually in attendance
          at a meeting. Avanir and AstraZeneca each shall bear all expenses of
          its JEC members related to such members' participation on the JEC and
          attendance at JEC meetings.

     6.2.3 Quorum. Notwithstanding what is stated in Section 6.2.2, the Co-Chair
          of AstraZeneca may call for a meeting by notifying Avanir no later
          than thirty (30) days in advance of a meeting of the JEC of the exact
          date, time and location for the meeting. Provided that (i) such notice
          has been timely issued and that the meeting is held on the date, time
          and place so indicated, or (ii) that Avanir confirms that it has been
          properly notified about the meeting, quorum shall be considered
          constituted at that meeting unless all members of one Party fail to
          attend the meeting because of illness, where no substitution could be
          reasonably arranged, breakdown in general communications, travel
          difficulties beyond the reasonable control of such Party, or by other
          similar reasons. No meeting shall be called for a day on which the
          commercial banks are closed in any of Great Britain, Sweden or the
          United States. For the purpose of agreeing that Avanir has been
          properly notified of the meeting in the case under (ii), attendance to
          a meeting without express objection thereto shall be sufficient.

     6.2.4 Decision-making. Any final decision mutually agreed to by the JEC
          shall be in writing and shall be conclusive and binding on the
          Parties. If such resolution regarding the initiation, planning or
          performance of the activities of the Research

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          Collaboration as described in Section 6.1.1 is unattainable by the JEC
          within *** days from the date the matter in dispute is first brought
          to the attention of the JEC, the dispute shall be resolved in
          accordance with ***; provided, however, that, subject to Section
          6.1.2, if the matter in dispute would result in additional expense
          being incurred by Avanir for activities not contemplated in the
          Research Plan, then AstraZeneca shall reimburse Avanir for such
          additional expense.

     6.2.5 Minutes. The JEC shall keep accurate minutes of its deliberations,
          which minutes shall record all proposed decisions and all actions
          recommended or taken. Drafts of minutes shall be delivered to the
          Co-Chairs of the JEC within twenty (20) days after the respective
          meeting. The Parties, on an alternating basis, shall prepare and
          circulate the draft minutes. Draft minutes shall be edited by the
          Co-Chairs and shall be issued in final form only with the approval and
          agreement of the Co-Chairs.

6.3  Upon Expiration or Termination of the Collaboration Term. Upon expiration
     or termination of the Collaboration Term the following shall apply:

     6.3.1 Dissolution of the RCMC and the JEC. The RCMC and the JEC shall be
          dissolved and Avanir shall provide AstraZeneca with consultation
          services, including reviewing and contributing to proposed
          publications concerning the Licensed Compounds or Licensed Products,
          as AstraZeneca may reasonably request for the Development Project,
          including by making Avanir's employees, consultants and other
          scientific staff available upon reasonable notice during normal
          business hours at their respective places of employment to consult
          with AstraZeneca on issues arising during the Development Project, or
          in connection with Exploitation of Licensed Compounds, Products or
          Results. AstraZeneca shall reimburse Avanir for out-of-pocket costs
          incurred in connection with such consultation services and should the
          time devoted by Avanir to such services

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          exceed *** FTE days in any Calendar Year, AstraZeneca shall compensate
          Avanir for any additional agreed upon FTE days. Prior to performing
          services in excess of the *** day allotment, Avanir shall notify
          AstraZeneca in writing that the said allotment has been utilised. For
          purposes of this Section 6.3.1, the daily FTE rate shall be determined
          by dividing the FTE Rate by ***.

     6.3.2 The Parties shall establish an Information Forum (the "IF"),
          consisting of between four (4) and eight (8) members with equal
          numbers appointed by the respective Party for the purpose of
          AstraZeneca gaining from the experience and expertise of Avanir and
          for keeping Avanir updated on AstraZeneca's activities in the
          Development Project. The IF shall meet on dates mutually agreed by the
          Parties once a year at a location suitable to both parties or by
          teleconference, videoconference or by other jointly suitable means.
          Avanir and AstraZeneca each shall bear all expenses of its IF members
          related to such members' participation on the IF and attendance at IF
          meetings.

     6.3.3 Avanir shall cease any and all use of the Licensed Know How, the
          Collaboration Results, the AstraZeneca Background Technologies, the
          AstraZeneca Improvements and any other AstraZeneca Confidential
          Information.

     6.3.4 Avanir shall deliver or return, as applicable, all data, files,
          records and other materials in its possession or control containing or
          comprising all AstraZeneca Background Technologies, AstraZeneca
          Improvements and AstraZeneca's Confidential Information (except one
          copy of AstraZeneca's Confidential Information which may be retained
          by Avanir solely for archival purposes).

     6.3.5 Avanir's obligation under Sections 6.3.1 through 6.3.4 shall, in
          addition to, and without limiting, what is stated therein, apply to
          each separate Licensed Compound which AstraZeneca has selected as a
          Candidate Drug in which

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          situation such obligations shall refer to such individual Licensed
          Compound or Licensed Improvement thereon, provided, however, that the
          RCMC and the JEC shall not be dissolved, and the IF not be
          established, until the expiration or termination of the Collaboration
          Term.

     6.3.6 Information Updates Regarding the AVP 26452 Compound and Other
          Compounds. At each quarterly meeting of the RCMC during the
          Collaboration Term, AstraZeneca shall provide Avanir an update on
          AstraZeneca's activities and progress regarding the AVP 26452 Compound
          and any other Licensed Compounds that has been selected as a CD by
          AstraZeneca. Such updates shall cover general information on
          AstraZeneca's development activities in the preceding quarter and a
          summary of the activities planned in the next twelve (12) months. For
          the avoidance of doubt, after the termination or expiration of the
          Collaboration Term, the AVP 26452 Compound and such other Licensed
          Compounds that have been selected as a CD by AstraZeneca shall be
          included in the regular information updates process for the
          Development Program as set forth in Sections 6.3.2 and 8.4.

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6.4  Transfer upon Termination of the Collaboration Term.

     Upon expiration or termination of the Collaboration Term the following
     shall apply:

     6.4.1 Avanir shall, and shall cause its majority-owned subsidiaries and its
          other Affiliates (which are its Affiliates both as of the Effective
          Date and at all relevant times thereafter) and use its best reasonable
          efforts to cause its Affiliates other than those referred to above to,
          without additional compensation, disclose and make available to
          AstraZeneca, to the extent not done so already, in whatever form
          AstraZeneca may reasonably request, Regulatory Documentation, copies
          of Licensed Know-How, Collaboration Results and any other Information
          claimed or covered by any Licensed Patent or Joint Patent or otherwise
          relating, directly or indirectly, to any Licensed Compound, Licensed
          Product or Licensed Improvement, and thereafter and throughout the
          term of the Agreement immediately upon the earlier of the development,
          making, conception or reduction to practice of each such Regulatory
          Documentation, Licensed Know-How or other Information.

     6.4.2 Avanir's obligation under Section 6.4.1 and under Section 6.4.4
          shall, in addition to, and without limiting, what is stated therein,
          apply to each separate Licensed Compound which AstraZeneca has
          selected as a Candidate Drug in which situation such obligations shall
          refer to such Regulatory Documentation, Licensed Know-How,
          Collaboration Results and Information relating directly or indirectly
          to that particular Licensed Compound or Licensed Improvement thereon.

     6.4.3 Avanir warrants that it will perform a reasonably diligent search for
          Licensed Know-How and Regulatory Documentation relevant to the safety,
          efficacy and Exploitation of Licensed Compounds and Licensed Products
          in existence as of the termination or expiration of the Collaboration
          Term and that all such located Licensed Know-How and Regulatory
          Documentation will be disclosed to AstraZeneca upon termination or
          expiration of the Collaboration Term.

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     6.4.4 Avanir, at its ***, will provide AstraZeneca with all reasonable
          assistance required in order to transfer the Licensed Know-How to
          AstraZeneca in a timely manner following termination or expiration of
          the Collaboration Term. Without prejudice to the generality of the
          foregoing, if visits of Avanir's representatives to AstraZeneca's
          facilities are reasonably requested by AstraZeneca for purposes of
          transferring the Licensed Know-How to AstraZeneca or for purposes of
          AstraZeneca acquiring expertise on the practical application of the
          Licensed Know-How or assisting on issues arising during such
          Exploitation, Avanir will send appropriate representatives to
          AstraZeneca's facilities, provided that AstraZeneca shall reimburse
          Avanir for its reasonable and verifiable expenses of travel and
          accommodations for such representatives and such persons' working
          hours actually devoted to such transfer or assistance at the FTE Rate.

7    REPORTS

7.1  Research Collaboration Progress Reports. No later than five (5) business
     days prior to each quarterly RCMC meeting, the Parties shall provide the
     RCMC with a detailed written progress report in English containing
     specifications and other information on all Collaboration Results generated
     by such party under the Research Collaboration and not previously reported
     to the RCMC. The RCMC may provide further instructions on the timing and
     content of these reports.

7.2  Copyrights. Copyrights to reports provided for hereunder are part of the
     Collaboration Results. Neither Party shall, without the prior written
     approval of the other Party, attribute to the other Party any abstract or
     interpretation of any such report for sales or promotion purposes.
     Notwithstanding the foregoing, each Party shall be entitled to make such
     number of copies of Collaboration Results as is reasonably required to
     perform its obligations under this Agreement and for archival purposes.

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8    DEVELOPMENT PROJECT

8.1  Diligence Obligations. AstraZeneca undertakes to:

     8.1.1 use Commercially Reasonable Efforts at its own cost and expense to
          develop a Licensed Product and to conduct all development necessary to
          obtain Health Registration Approvals for a Licensed Product for use in
          humans (including the indication for ***) in each of the Major Markets
          and throughout the Territory; and

     8.1.2 use Commercially Reasonable Efforts to commercialise a Licensed
          Product for use in humans (including the indication for ***) in each
          of the Major Markets and throughout the Territory; provided, however,
          that such obligations are expressly conditioned upon Avanir and its
          Affiliates performing their respective obligations hereunder,
          including the completion of the activities under the Research
          Collaboration and the information disclosure requirements pursuant to
          Section 5.4, and such obligations of AstraZeneca shall be delayed or
          suspended as long as any such condition exists; and provided further,
          for the avoidance of doubt, that AstraZeneca shall not be obligated to
          obtain Health Registration Approval for, or commercialise, more than
          one Licensed Product in any Major Market and throughout the Territory.
          In the event that AstraZeneca decides to discontinue the development
          or commercialisation of a Licensed Product in favour of another
          Licensed Product, its obligations under this Section 8.1.2. shall
          cease with respect to such initial Licensed Product in favour of such
          other Licensed Product. AstraZeneca shall perform its obligation under
          this Section 8.1.2. in good scientific manner and in compliance in all
          material respects with all Applicable Law.

     8.1.3 Should the use by AstraZeneca of its Commercially Reasonable Efforts
          have as a consequence that AstraZeneca would be obligated to carry out
          some or all of the

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          activities provided for in Section 8.1.1 or 8.1.2 in a country in
          which such activities would not, in AstraZeneca's reasonable
          judgement, make commercial sense then AstraZeneca shall,
          notwithstanding what is stated in Sections 8.1.1 and 8.1.2 and
          following consultation with Avanir, be allowed to refrain from
          carrying out such activity(ies) in such country, other than a Major
          Market, ***.

     8.1.4 Upon satisfaction of its obligations under Sections 8.1.1 and 8.1.2,
          AstraZeneca shall be deemed to have satisfied all diligence
          obligations owed to Avanir hereunder, with respect to the Exploitation
          of the Licensed Compounds, Licensed Products or Collaboration Results,
          and shall have no other obligation, express or implied, to Exploit the
          Licensed Compounds, Licensed Products or Collaboration Results.

8.2  Breach of Diligence Obligations.

     8.2.1 Notification and Meeting. If at any time Avanir has a reasonable
          basis to believe that AstraZeneca is in breach of its material
          obligations under Section 8.1, then Avanir shall so notify
          AstraZeneca, specifying the basis for its belief, and the Parties
          shall meet within thirty (30) days after such notice to discuss in
          good faith Avanir's concerns and AstraZeneca's development and
          commercialisation plans with respect to the Licensed Compound and
          Licensed Product.

     8.2.2 Right of Termination. If, after such good faith discussions mentioned
          in Section 8.2.1, (a) AstraZeneca is in breach of its obligations
          under Section 8.1, and (b) AstraZeneca does not take reasonable steps
          designed to rectify such breach within ninety (90) days of meeting
          with Avanir pursuant to Section 8.2.1 (or, if such failure cannot be
          rectified within such ninety (90)-day period, if AstraZeneca does not
          commence actions to rectify such breach within such period and
          thereafter

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          diligently pursues such actions), Avanir may exercise its right of
          termination provided under Section 21.5.

8.3  Services in Relation to the AVP 26452 Compound. Avanir shall provide
     AstraZeneca with consultation services, including reviewing and
     contributing to proposed publications concerning the AVP 26452 Compound, as
     AstraZeneca may reasonably request for the Development Project, including
     by making Avanir's employees, consultants and other scientific staff
     available to consult with AstraZeneca on issues arising during the
     pre-clinical or clinical development of the AVP 26452 Compound, or in
     connection with Exploitation of the AVP 26452 Compound or the AVP 26452
     Product. For this purpose AstraZeneca may use during the Collaboration Term
     the FTEs at Avanir funded by AstraZeneca in accordance with Section 9.1 and
     thus no additional funding shall be provided by AstraZeneca to Avanir to
     obtain the consultation services provided for in this Section 8.3; unless
     the delivery of such services rises to a level that makes it impracticable
     for Avanir to fulfil its responsibilities under the Research Plan. After
     termination or expiration of the Collaboration Term, the payment shall
     follow the reimbursement scheme set forth in Section 6.3.1. The failure of
     Avanir to fulfil its obligations to provide consultation services shall not
     give rise to a right in AstraZeneca to terminate this Agreement. For the
     avoidance of doubt, Avanir shall provide the services described in Section
     3.9.

8.4  Reporting. Following termination or expiration of the Research
     Collaboration AstraZeneca shall provide Avanir in reasonable connection to
     the meetings in the IF with an annual report on the development (the
     "DEVELOPMENT REPORT") of Licensed Products in the Territory in order to
     keep Avanir informed of its progress. Such report shall cover, in relation
     to Licensed Compounds and Licensed Products, general information on
     AstraZeneca's development activities in the previous *** months, a summary
     of the activities planned in the next *** months, and a timetable of
     planned and actual

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     submissions for Health Registration Approvals. If and when a Health
     Registration Approval is obtained in any country of the Territory,
     AstraZeneca shall promptly inform Avanir thereof.

8.5  Licensed Improvements. For purposes of the obligations in Sections 8.1, 8.2
     and 8.3, a Licensed Product shall include any Licensed Improvement.

9    RESEARCH FUNDING

9.1  Funding.

     9.1.1 Each Party shall assume responsibility for its own costs and expenses
          for the Research Collaboration with the sole exception that
          AstraZeneca shall provide funding to Avanir (i) during the first
          Collaboration Year for *** FTEs; and (ii) for at least *** and no more
          than *** FTEs per each Collaboration Year thereafter during the
          Collaboration Term at the FTE Rate. Such AstraZeneca's obligation
          shall be contingent upon Avanir making the corresponding number of
          FTEs available for the Research Collaboration. In addition to being
          available for the Research Collaboration such FTE's funded by
          AstraZeneca in accordance herewith, shall also be available for such
          consulting services provided for under Section 8.3.

     9.1.2 The JEC shall no later than *** prior to the expiration of a certain
          Collaboration Year decide in writing the number of FTEs to be funded
          by AstraZeneca during the immediately subsequent Collaboration Year;
          provided that the number of FTEs to be funded by AstraZeneca shall be
          no less than *** FTEs in any given year during the Collaboration Term.

     9.1.3 Subject to mutual agreement between the Parties, which agreement each
          Party may enter into at its sole discretion, AstraZeneca may provide
          funding for FTEs

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          for a certain period of time, to be decided by the Parties, beyond the
          third Collaboration Year.

9.2  Invoices. Thirty (30) days prior to the commencement of each Calendar
     Quarter, Avanir shall invoice AstraZeneca for amounts due to Avanir from
     AstraZeneca pursuant to Section 9.1 based on the FTE Rate for the ensuing
     Calendar Quarter. Each invoice shall be sent to the AstraZeneca Principal
     Scientist and shall be accompanied by a forecast of the number and purpose
     of the FTEs to be provided by Avanir in the Research Collaboration during
     such ensuing Calendar Quarter and a report from Avanir's time reporting
     system on FTE effort spent in relation to the Research Collaboration during
     the immediately preceding Calendar Quarter, if any. AstraZeneca hereby
     acknowledges that Avanir does not maintain a timesheet system and that the
     requirements of this Agreement do not require Avanir to implement any such
     system. The Parties confirm, however, that such documentation mentioned in
     Section 9.3.1 shall be required for the purpose of reporting FTEs devoted
     to the Research Collaboration as set forth in this Section 9.2. No later
     than thirty (30) days after the end of each Collaboration Year Avanir shall
     send a report relating to the FTEs provided by Avanir to the Research
     Collaboration during such Collaboration Year. Without prejudice to any
     other remedy available to AstraZeneca, any amount paid by AstraZeneca for
     which Avanir has not provided the corresponding number of FTEs during such
     Collaboration Year may be deducted by AstraZeneca from subsequent payments
     to be made by AstraZeneca to Avanir for FTE funding hereunder and, if
     necessary to recover the amount, from milestone payments and royalty
     payments.

     Each invoice shall be payable to Avanir within thirty (30) days after
     receipt by AstraZeneca of a correct invoice with supporting documentation.
     Payment shall be made to such bank account as Avanir shall have notified
     AstraZeneca in writing.

9.3  Records Retention; Audit.

     9.3.1 Avanir shall keep or cause to be kept accurate records or books of
          account in accordance with applicable generally accepted accounting
          principles that, in reasonable detail, fairly reflect the reimbursable
          FTEs. Such books and records shall include attendance records, records
          of the allocation of FTEs to the Research

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          Collaboration, and the accomplishment of activities measured against
          the Research Plan, and shall be maintained by Avanir for at least ***
          years following the end of the Calendar Year to which they pertain or
          such longer period of time required by Applicable Law.

     9.3.2 Upon the written request of AstraZeneca, Avanir shall permit a
          certified public accountant or a person possessing similar
          professional status and associated with an independent accounting firm
          reasonably acceptable to the Parties to inspect during regular
          business hours and no more than once *** and going back no more than
          *** years after receipt of the respective invoice and report pursuant
          to Section 9.2, nor more than once with respect to any such year, all
          or any part of Avanir's records and books necessary to verify such
          invoices and reports. The accounting firm shall enter into appropriate
          obligations with Avanir to treat all information it receives during
          its inspection in confidence. The accounting firm shall disclose to
          Avanir and AstraZeneca only whether such invoices and reports are
          correct and details concerning any discrepancies, but no other
          information shall be disclosed to AstraZeneca. The charges of the
          accounting firm shall be paid by AstraZeneca, except that if the FTEs
          allocated to the Research Collaboration were less than *** percent
          (***%) of what was required from Avanir during the period under
          review, the charges shall be paid by Avanir.

10   CONSIDERATION

10.1 Total obligation. The research funding to be provided by AstraZeneca to
     Avanir pursuant to Article 9 together with the payments payable by
     AstraZeneca to Avanir pursuant to this Article 10 represent all of
     AstraZeneca's financial obligations to Avanir hereunder and Avanir shall
     not be entitled to any additional compensation or remuneration from
     AstraZeneca under this Agreement. In consideration of the licences and
     other rights

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     granted by Avanir to AstraZeneca herein and subject to the terms and
     conditions of this Agreement, AstraZeneca shall make the following payments
     to Avanir:

     10.1.1 Research Reimbursement Payment. AstraZeneca shall pay to Avanir ten
          million U.S. Dollars ($10,000,000) within fifteen (15) days of the
          Effective Date.

     10.1.2 Development Milestones. Within forty-five (45) days of achievement
          of each respective milestone as described in this Section 10.1.2 for
          the first Licensed Compound or Licensed Product, AstraZeneca shall
          make the corresponding payment to Avanir as follows:

          (a)  *** U.S. Dollars ($***) following the earlier of (i) the ***, and
               (ii) the ***;

          (b)  *** U.S. Dollars ($***) following the ***;

          (c)  *** U.S. Dollars ($***) following the ***;

          (d)  *** U.S. Dollars ($***) following the date of ***;

          (e)  *** U.S. Dollars ($***) following ***; and

          (f)  *** U.S. Dollars ($***) following ***; and

          (g)  *** U.S. Dollars ($***) following ***; and

          (h)  *** U.S. Dollars ($***) following ***; and

          (i)  *** U.S. Dollars ($***) following ***; and

          (j)  *** U.S. Dollars ($***) following ***;

          provided always that (i) when a milestone payment becomes due under
          any of sub-sections (h) through (j) the geographically corresponding
          milestone payment under sub-sections (e) through (g) shall also become
          due, unless, for the avoidance of doubt, such milestone has become due
          at a previous occasion; and (ii) should the first milestone payment
          under sub-sections (h) through (j) become

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          due (the date thereof the "Due Date") after the first milestone
          payment having become due under Section 10.1.5, then the aggregate
          amount paid under Section 10.1.5 up until the Due Date shall be
          deducted from the milestone payments to be made under sub-sections (h)
          through (j) until fully deducted.

     10.1.3 Milestones for Additional Indications. Within forty-five (45) days
          of the achievement of each respective milestone as described in this
          Section 10.1.3 for the first Licensed Compound or Licensed Product
          within an Other Indication, AstraZeneca shall make the corresponding
          payment to Avanir as follows:

          (a)  *** U.S. Dollars ($***) following ***;

          (b)  *** U.S. Dollars ($***) following ***;

          (c)  *** U.S. Dollars ($***) following ***; and

          (d)  *** U.S. Dollars ($***) following ***.

     10.1.4 Commercial Milestones on Annual Net Sales. At the end of the
          Calendar Quarter in which the Annual Net Sales of the first Licensed
          Product exceeds each respective milestone set forth below for the
          first time, AstraZeneca shall make the corresponding payment to
          Avanir, as follows:

          (a)  *** U.S. Dollars ($***) within *** days of the end of the
               Calendar Quarter in which the Annual Net Sales of a Licensed
               Product exceeds for the first time *** U.S. Dollars ($***); and

          (b)  *** U.S. Dollars ($***) within *** days of the end of the
               Calendar Quarter in which the Annual Net Sales of a Licensed
               Product exceeds for the first time *** U.S. Dollar ($***); and

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          (c)  *** U.S. Dollars ($***) within *** days of the end of the
               Calendar Quarter in which the Annual Net Sales of a Licensed
               Product exceeds for the first time *** U.S. Dollars ($***).

          For the avoidance of doubt, in order to qualify for a payment under a)
          - d) the Annual Net Sales shall emanate from Licensed Products based
          on the ***.

     10.1.5 Commercial Milestones on Aggregate Net Sales. At the end of the
          Calendar Quarter in which the cumulative Net Sales of the first
          Licensed Product under a Health Registration Approval on the basis of
          a Surrogate Marker for which no milestone under Section 10.1.2(h),(i)
          or (j) has become due exceeds for the first time each respective
          milestone set forth below, AstraZeneca shall make the corresponding
          payment to Avanir, as follows:

          (a)  *** U.S. Dollars ($***) within *** days of the end of the
               Calendar Quarter in which the cumulative Net Sales exceeds for
               the first time *** U.S. Dollars ($***); and

          (b)  *** U.S. Dollars ($***) within *** days of the end of the
               Calendar Quarter in which the cumulative Net Sales exceeds for
               the first time *** U.S. Dollars ($***); and

          (c)  *** U.S. Dollars ($***) within *** days of the end of the
               Calendar Quarter in which the cumulative Net Sales exceeds for
               the first time *** U.S. Dollars ($***); and

          (d)  *** U.S. Dollars ($***) within *** days of the end of the
               Calendar Quarter in which the cumulative Net Sales exceeds for
               the first time *** U.S. Dollars ($***).

          provided, however, that upon the first milestone payment under Section
          10.1.2(h) through (j) becoming due, no further milestone payment under
          this Section shall

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          become due. For the avoidance of doubt, in order to qualify for a
          payment under subsections (a) through (d) above, the Net Sales shall
          emanate from Licensed Products based on ***.

     10.1.6 Each of the payments under Section 10.1.2 through 10.1.5 shall be
          made by AstraZeneca no more than once under this Agreement,
          collectively amounting to an aggregate maximum amount of three hundred
          and thirty million U.S. Dollars ($330,000,000), irrespective of the
          number of Licensed Compounds or Licensed Products that have achieved
          the milestone events set forth in Sections 10.1.2 through 10.1.5, or
          the number of countries or Major Markets in which such milestone
          events have been achieved.

10.2 Royalties

     In addition to the payments under Section 10.1.2 through 10.1.5,
     AstraZeneca shall pay Avanir, with respect to each Licensed Product, the
     following royalties on the Annual Net Sales of Licensed Products, on a ***
     basis, in the Territory (provided that calculations for the Combination
     Products are to be made in accordance with the formula set out in Section
     10.3 and provided further that calculations for Sublicensee income are to
     be made in accordance with Section 10.4):

          (a)  *** percent (***%) of Net Sales for that portion of Annual Net
               Sales of such Licensed Product in the Territory that is less than
               *** U.S. Dollars ($***);

          (b)  *** percent (***%) of Net Sales for that portion of Annual Net
               Sales of such Licensed Product in the Territory that equals or
               exceeds *** U.S. Dollars ($***) but is less than *** U.S. Dollars
               ($***);

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          (c)  *** percent (***%) of Net Sales for that portion of Annual Net
               Sales of such Licensed Product in the Territory that equals or
               exceeds *** U.S. Dollars ($***) but is less than *** U.S. Dollars
               ($***); and

          (d)  ***percent (***%) of Net Sales for that portion of Annual Net
               Sales of such Licensed Product in the Territory that equals or
               exceeds *** U.S. Dollars ($***).

     For the avoidance of doubt, the calculation of royalties under this Section
     10.2 shall be conducted separately for each Licensed Product. Thus, if
     AstraZeneca sells more than one Licensed Product in the Territory, the
     thresholds and ceilings in subsections (a) to (d) shall apply *** where a
     Licensed Product is deemed to be all Licensed Products based on the ***.

10.3 Combination Products. With respect to Combination Products, the Net Sales
     used for the calculation of the royalties under Section 10.2 shall be
     determined as follows:

       A         Net Sales of the Combination
     -----   X   Product, where:
      A+B

     A =   *** of the Licensed Product, containing the ***, in the given
           country.

     B =   *** of the ready-for-sale form of a product containing the ***,
           in the given country.

     In the event, however, that, in a specific country, (a) the other
     therapeutically active ingredient(s) in such Combination Product are not
     sold separately in such country, Net Sales shall be adjusted by multiplying
     *** of such Combination Product by the fraction

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     A/C, where C is the ***, and (b) if a Licensed Product containing such
     Licensed Compound(s) is not sold separately, Net Sales shall be calculated
     by multiplying actual Net Sales of such Combination Product by the fraction
     (C-B)/C, where B is the *** and C is the ***. The standard sales price for
     the Licensed Product containing such Licensed Compound(s) and for each
     other active ingredient shall be for a quantity comparable to that used in
     such Combination Product and of the same class, purity and potency. If, in
     a specific country, both a Licensed Product containing the Licensed
     Compound(s) and a product containing the other active ingredients in such
     Combination Product are not sold separately, a market price for such
     Licensed Product and such other active ingredients shall be negotiated by
     the Parties in good faith based upon the costs, overhead and profit as are
     then incurred for such Combination Product and all products then being made
     and marketed by AstraZeneca and having an ascertainable market price that
     are comparable to such Licensed Product or such other active ingredients,
     as applicable. If, in a specific country, the foregoing calculations do not
     fairly represent the value of the various active ingredients included in a
     Combination Product or such prices cannot be determined for all active
     ingredients by using such aforesaid method, the allocation of Net Sales for
     such Combination Product shall be negotiated by the Parties in good faith
     based on the relative value contributed by each component, such agreement
     not to be unreasonably withheld or delayed.

10.4 Sublicensees. AstraZeneca shall not grant sublicenses under any or all of
     this Agreement in *** without the prior express written consent of Avanir;
     provided, however, no such consent shall be required in the event (i)
     AstraZeneca demonstrates that pursuant to each such sublicense, the
     reasonably anticipated economic benefits to Avanir will be no less
     favourable on the whole than if the definition of "Net Sales" had applied
     equally to the gross invoiced amount on sales of the Licensed Product by
     Sublicensees under the sublicensing arrangement proposed; (ii) that such
     sublicense was granted in order to

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     satisfy concerns of Competition/Anti Trust authorities in *** or that a
     sublicence was otherwise compelled to be granted pursuant to Applicable
     Law; or (iii) AstraZeneca confirms in writing to Avanir that it will pay
     royalties to Avanir from the sublicensing arrangement proposed by applying
     for such arrangement a definition of the Net Sales as mentioned under
     sub-clause (i). With respect to sublicenses granted by AstraZeneca outside
     the *** as set forth under sub-clause (ii)), AstraZeneca shall pay to
     Avanir an amount equal to *** percent (***%) of all sublicensing revenues
     received by it or its Affiliates from Sublicensees whether comprising
     license fees, milestone payments, royalties in respect of sales of Licensed
     Product or Licensed Compound by Sublicensees to Third Parties, or other
     similar or dissimilar payments in respect of the sublicensing of rights
     under this Agreement and the right to commercialise Licensed Products and
     Licensed Compounds. All such amounts received by AstraZeneca and its
     Affiliates upon which Avanir is paid *** percent (***%) shall be deemed to
     be Net Sales for the purpose of deciding the Annual Net Sales under Section
     10.2 and shall be counted before any Net Sales received by AstraZeneca by
     other means.

10.5 Reduction of Royalty.

     10.5.1 Competition.

          (a)  In the event that, in a country in the Territory, generic
               competition with respect to a Licensed Product occurs by products
               having (a) the same active compound as the Licensed Compound
               included in such Licensed Product or (b) a similar molecule
               (where "similar molecule" means a chemical compound that is
               claimed or covered by a Licensed Patent, a Joint Patent or an
               AstraZeneca Patent) (each such product, a "COMPETING PRODUCT"),
               and Net Sales of Licensed Products in such country drop in excess
               of *** percent (***%) in a given Calendar Quarter compared to the
               immediately preceding Calendar Quarter, then, subject to Section
               10.5.1

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               (b), for purposes of calculating the royalties of such Licensed
               Product under Section 10.2 *** percent (***%) of the Net Sales in
               such country shall be disregarded.

          (b)  Should the situation contemplated in Section 10.5.1 (a) occur in
               a country following the expiration of the period stated in
               Section 10.8.1 (a) or 10.8.2 (a), as applicable, for such country
               then for the purposes of calculating the royalties of such
               Licensed Product under Section 10.2 *** percent (***%) of the Net
               Sales in such country shall be disregarded.

          (c)  The calculation of the royalty reduction under this Section
               10.5.1 shall be conducted separately for each Licensed Product
               where each separate Licensed Product is deemed to be all Licensed
               Products based on the ***.

          (d)  If the number of units sold of a Competing Product represents ***
               percent (***%) of the aggregate number of units sold of all
               products within the same ATC class as the Licensed Product
               concerned, including Licensed Products, in a country in the
               Territory as reported by IMS or any comparable reporting agency
               in a Calendar Year, then AstraZeneca shall have the right to
               withdraw the relevant Licensed Product from sale in the country,
               but such withdrawal shall not constitute a termination of
               AstraZeneca's rights to such Licensed Products in that country.

     10.5.2 Compulsory Licences. In the event that a court or a governmental
          agency of competent jurisdiction requires AstraZeneca or an
          AstraZeneca Affiliate or Sublicensee to grant a compulsory licence to
          a Third Party permitting such Third Party to make and sell the
          Licensed Product in a country in the Territory, then for the purposes
          of calculating the royalties of such Licensed Product under Section
          10.2, the applicable royalty rate shall be *** to that applicable to
          the compulsory

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          license, if ***. The calculation of the royalty *** under this Section
          10.5.2 shall be conducted separately for each Licensed Product.

     10.5.3 No Valid Claim. In the event that, and in such case from and after
          the date on which, a Licensed Product is Exploited in a country and is
          not covered by a Valid Claim in such country, then for the purposes of
          calculating the royalties of such Licensed Product under Section 10.2,
          *** percent (***%) of the Net Sales in such country shall be
          disregarded. The calculation of the royalty *** under this Section
          10.5.3 shall be conducted separately for each Licensed Product.

10.6 Royalty Stacking.

     10.6.1 For Licensed Products sold by AstraZeneca or its Affiliates to Third
          Parties (including Distributors), where the sum of royalty payments
          owed by AstraZeneca and its Affiliates to Avanir and any Third Parties
          exceeds *** percent (***%) of Net Sales for a given Licensed Product,
          the royalty rate payable to Avanir shall be *** such that the
          aggregate royalty rate payable on such Licensed Product, were all
          Third Party royalties similarly ***, does not exceed *** percent
          (***%) of Net Sales thereof.

     10.6.2 In the case of a Licensed Product developed or commercialised by a
          Sublicensee of AstraZeneca, where the payment of royalties by
          AstraZeneca to Avanir is based upon "Net Sales" of the Sublicensee as
          contemplated in clause (iii) of Section 10.4, the royalty *** set
          forth in Section 10.5 and Section 10.6.1, to the extent applicable,
          will apply.

10.7 Any *** set forth in Sections 10.5 and 10.6 shall be applied to the royalty
     rate payable to Avanir under Section 10.2 in the order in which the event
     triggering such *** occurs. Notwithstanding the foregoing, in no event
     shall the royalty rate payable to Avanir under Section 10.2 be *** by more
     than *** percent (***%) in any Calendar Quarter as a result

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     of the cumulative *** set forth in Sections 10.5 and 10.6, provided,
     however, that in the event of a royalty *** under Section 10.5.1 b) the
     royalty rate payable to Avanir under Section 10.2 may be *** by up to ***
     percent (***%). Credits not exhausted in any Calendar Quarter may be
     carried into future Calendar Quarters, subject to the foregoing sentence.

10.8 Royalty Term. AstraZeneca's obligation to pay royalties (for the avoidance
     of doubt including such amounts paid by AstraZeneca to Avanir under Section
     10.4) shall commence, on a country-by-country basis, with respect to each
     separate Licensed Product, on the date of *** of such Licensed Product in
     such country. The obligation shall expire, on a country-by-country basis,
     with respect to each separate Licensed Product:

     10.8.1 in the case of any ***, on the later to occur of (a) the ***
          anniversary of the First Commercial Sale of each Licensed Product,
          respectively, in *** and (b) the expiration date in such country of
          the *** to expire of any issued Licensed Patent, Joint Patent or
          AstraZeneca Patent that includes at least one Valid Claim covering the
          sale of such Licensed Product in such country; or

     10.8.2 in the case of any ***, on the later to occur of (a) the ***
          anniversary of the First Commercial Sale of each Licensed Product,
          respectively, in such country and (b) the expiration date in such
          country of the *** to expire of any issued Licensed Patent, Joint
          Patent or AstraZeneca Patent that includes at least one Valid Claim
          covering the sale of such Licensed Product in such country.

10.9 Sales Subject to Royalties. Sales between AstraZeneca, its Affiliates and
     Sublicensees shall not be subject to royalties hereunder. Royalties shall
     be calculated on AstraZeneca's and its Affiliates' sale of the Licensed
     Products to a Third Party (including Distributors). Royalties shall be
     payable only once for any given batch of the Licensed Products. For
     purposes of determining Net Sales, the Licensed Product shall be deemed

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     to be sold when *** and a "sale" shall not include, and no royalties shall
     be payable on, *** by AstraZeneca, its Affiliates or Sublicensees of free
     samples of Licensed Products or clinical trial materials containing
     Licensed Compound, or *** of Licensed Products to patients under *** in the
     United States or any similar programmes in other countries or other
     transfers or dispositions for *** other than as therapeutic pharmaceutical
     product in humans where AstraZeneca receives no compensation or
     identifiable benefit therefrom. For the avoidance of doubt, AstraZeneca
     shall pay Avanir royalties on *** of Licensed Products or Licensed
     Compounds in the circumstances described in the immediately preceding
     sentence if such *** result in revenue to AstraZeneca.

10.10 Royalty Payments. The royalties shall be calculated quarterly as of the
     last day of March, June, September and December respectively, for the
     Calendar Quarter ending on that date. AstraZeneca shall pay the royalties
     in conjunction with the delivery of a written report to Avanir within sixty
     (60) days after the end of each Calendar Quarter that shows, with respect
     to each country and each Licensed Product, the sales volume and Net Sales
     of the Licensed Products during such Calendar Quarter.

10.11 Licensed Improvements. For purposes of this Article 10, Licensed Products
     shall include Licensed Improvements, if any.

10.12 Records Retention; Audit.

     10.12.1 Until the *** anniversary of the Calendar Year in which a Licensed
          Product is sold, AstraZeneca shall keep or cause to be kept accurate
          records or books of account in accordance with applicable generally
          accepted accounting principles showing the information that is
          necessary for the accurate determination of the royalties due
          hereunder with respect to the sale of such Licensed Product.

     10.12.2 Upon the written request of Avanir, AstraZeneca shall permit a
          certified public accountant or a person possessing similar
          professional status and associated with

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          an independent accounting firm acceptable to the Parties to inspect
          during regular business hours and no more than *** a year and no more
          than once with respect to any such year and going back no more than
          *** years preceding the current year, all or any part of AstraZeneca's
          records and books necessary to check the accuracy of the royalties
          paid. The accounting firm shall enter into appropriate obligations
          with AstraZeneca to treat all information it receives during its
          inspection in confidence. The accounting firm shall disclose to Avanir
          and AstraZeneca only whether the royalty reports are correct and
          details concerning any discrepancies, but no other information shall
          be disclosed to Avanir. The charges of the accounting firm shall be
          paid by ***, except that if the royalties have been understated by
          more than the lesser of (i) *** percent (***%) and (ii) $***, the
          charges shall be paid by ***. AstraZeneca shall promptly pay any
          shortages in royalty payments regardless of amount, together with
          interest calculated at the rate of *** percent (*** %) per month or
          such lesser maximum rate permitted by law. Any failure by Avanir to
          exercise its right under this Section 10.12.2 with respect to a
          Calendar Year within the time period allotted therefore, shall
          constitute a waiver by Avanir of its right to later object to any
          payments made by AstraZeneca under this Agreement during such Calendar
          Year.

10.13 Mode of Payment. All payments set forth in this Article 10 shall be
     remitted by wire transfer to the following bank account of Avanir or such
     other account as Avanir may designate in writing to AstraZeneca:

     ***

10.14 Currency. All payments required under Article 9 and this Article 10 shall
     be made in U.S. Dollars. For the purpose of computing the Net Sales of
     Licensed Products sold in a currency other than U.S. Dollars, such currency
     shall be converted from local currency to

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     U.S. Dollars by AstraZeneca in accordance with the rates of exchange for
     the relevant month for converting such other currency into U.S. Dollars
     used by AstraZeneca's internal accounting systems on a consistent
     company-wide basis, which are independently audited on an annual basis.

10.15 Taxes.

     10.15.1 General. The royalties, milestones and other amounts payable by
          AstraZeneca to Avanir pursuant to this Agreement ("PAYMENTS") shall
          not be reduced on account of any taxes unless required by Applicable
          Law. Avanir alone shall be responsible for paying any and all taxes
          (other than withholding taxes or deduction of tax at source required
          by Applicable Law to be paid by AstraZeneca) levied on it by account
          of its receipt of any Payments it receives under this Agreement.
          AstraZeneca shall deduct or withhold from the Payments any taxes that
          it is required by Applicable Law to deduct or withhold.
          Notwithstanding the foregoing, if Avanir is entitled under any
          applicable tax treaty to a reduction of the rate of, or the
          elimination of, applicable withholding tax, it may deliver to
          AstraZeneca or the appropriate governmental authority (with the
          assistance of AstraZeneca to the extent that this is reasonably
          required and is expressly requested in writing) the prescribed forms
          necessary to reduce the applicable rate of withholding tax or to
          relieve AstraZeneca of its obligation to withhold tax, and AstraZeneca
          shall apply the reduced rate of withholding tax, or dispense with
          withholding tax, as the case may be, provided that AstraZeneca has
          received evidence, in a form satisfactory to AstraZeneca, of Avanir's
          delivery of all applicable forms (and, if necessary, its receipt of
          appropriate governmental authorization) at least fifteen (15) days
          prior to the time that the Payments are due. If, in accordance with
          the foregoing, AstraZeneca withholds any amount, it shall pay to
          Avanir the balance when due, make timely payment to the proper taxing
          authority of the withheld amount, and send to Avanir proof of such
          payment within thirty (30) days following that payment. For the
          purposes of this

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          Agreement, the stated amount of the Payments payable by AstraZeneca
          shall include any sales tax that Avanir may be required to collect.

     10.15.2 Indirect Taxes. Notwithstanding anything contained in Section
          10.15.1, this Section 10.15.2 shall apply with respect to Indirect
          Taxes. Each of the Parties shall be responsible for the payment of
          Indirect Taxes assessed against it by law. If any Indirect Taxes are
          chargeable in respect of any Payments, AstraZeneca shall pay such
          Indirect Taxes at the applicable rate in respect of any such Payments
          following the receipt, where applicable, of an Indirect Taxes invoice
          in the appropriate form issued by Avanir in respect of those Payments,
          such Indirect Taxes to be payable on the due date of the payment of
          the Payments to which such Indirect Taxes relates.

     10.15.3 Imports. For the avoidance of doubt, the Parties acknowledge and
          agree that none of the milestones or royalties payable under this
          Agreement are related to the licence (or right) to import or any
          import of Licensed Products. The receiving Party shall be responsible
          for any import clearance, including payment of any import duties and
          similar charges, in connection with any Licensed Products transferred
          to such Party under this Agreement. The Parties shall co-operate in
          accordance with Applicable Law to ensure where permissible no duties
          are paid on imported clinical products. Where duties are payable, the
          Parties shall co-operate to ensure that the Party responsible for
          shipping values the clinical product in accordance with Applicable
          Laws and minimises where permissible any such duties and related
          import taxes that are not reclaimable from the relevant authorities.

11   REIMBURSEMENT OF DEVELOPMENT STOCK AND PRE-CLINICAL STUDIES

11.1 Orders Placed with ***

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     11.1.1 Development Stock. As of the Effective Date Avanir has ordered, for
          the amount of *** kilograms of Good Manufacturing
          Practices quality AVP 26452 Compound (the "***").

     11.1.2 Preformulation, Formulation Development and Clinical Manufacturing.
          As of the Effective Date Avanir has ordered, from *** of the AVP 26452
          Compound (the "***") of a quality and with characteristics, and
          otherwise in accordance with Good Manufacturing Practices and the
          specifications and other terms, sufficient to use it for clinical
          trials concerning the AVP 26452 Compound and otherwise in the
          Development Project in accordance with Good Clinical Practice (the
          "***"). The *** will be delivered by ***.

     11.1.3 *** Toxicology Study in Monkeys. As of the Effective Date Avanir has
          ordered, for an amount not exceeding *** U.S. Dollars ($***), from ***
          toxicology study of AVP 26452 in monkeys (the "***"). The study will
          be conducted in compliance with current Good Laboratory Practices and
          will suitable for use in future regulatory filings.

11.2 Contractual Relationships. The Parties recognise that the ***, the *** and
     the *** are contractual relationships solely between Avanir and ***, and
     Avanir and ***, and Avanir and ***, respectively although under the terms
     of these Orders Avanir has the right to assign its rights under each Order
     to AstraZeneca. Upon AstraZeneca's written notice to Avanir, Avanir shall
     assign the *** or the *** or the ***, whichever is provided for in the
     notice, to AstraZeneca at no additional cost in accordance with its terms.
     Unless and until such respective Order is so assigned to AstraZeneca Avanir
     undertakes to use its reasonable commercial efforts at all times during the
     term of the relevant Order to enforce its rights under such Order against
     ***, ***, or ***, whichever is applicable, and to allow AstraZeneca to
     recommend action to be taken, and comment on each proposed

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     action to be taken, which recommendations and comments Avanir shall take
     into reasonable account.

11.3 Reimbursement for ***, *** and ***. AstraZeneca shall, under the express
     condition that the *** is suitable for conversion into Good Manufacturing
     Practices quality AVP 26452 Compound, that the *** are in compliance with
     Section 11.1.2 hereof and that the *** is in compliance with Section
     11.1.3, reimburse Avanir for any amounts paid to ***, *** and *** under the
     orders mentioned under Section 11.1. The Parties hereby acknowledge a need
     for receipt of *** of Licensed Product *** to conduct anticipated studies.
     The *** presently calls for only ***. AstraZeneca shall reimburse to Avanir
     the cost of procuring such *** of *** of Licensed Product (including the
     ***) provided, however, Avanir shall be responsible for such costs to the
     extent they exceed, together with the costs under the current ***, ***
     percent (***%) of the ***.

     For the avoidance of doubt, in connection with any such reimbursement,
     AstraZeneca shall be entitled to the benefit of any ***, whether credited
     at the time of payment or paid thereafter to Avanir. Such *** shall be
     deducted, in accordance with the terms of the respective Order provided
     always, for the avoidance of doubt, that such terms are in compliance with
     Section 11.1 hereof. Such reimbursement shall be made within *** days of
     AstraZeneca receiving invoices thereon, such invoices to be issued (a) no
     earlier than on the Effective Date for payments made by Avanir prior to the
     Effective Date, and (b) no earlier than within *** days after payment is
     made by Avanir, for any payments made after the Effective Date by Avanir.
     Notwithstanding anything to the contrary stated herein, under no
     circumstances will the amount reimbursable hereunder by AstraZeneca exceed
     *** U.S. Dollars ($***). Immediately upon reimbursement by AstraZeneca
     under this Section 11.3, all right, title and interest in and to the
     Development Stock shall transfer from Avanir to AstraZeneca without
     additional consideration.

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12   OWNERSHIP OF INTELLECTUAL PROPERTY

12.1 Ownership of Collaboration Results. The Parties shall each own an ***
     interest in any and all Collaboration Results. Each Party shall promptly
     disclose to the other Party in writing the development, making, conception
     or reduction to practice of any Collaboration Results, and shall, and does
     hereby, assign, and shall cause its majority-owned subsidiaries (and its
     other Affiliates which are Affiliates both as of the Effective Date and
     during the relevant periods referred to above) and its and their employees
     and agents, as applicable, and use its best reasonable efforts to cause its
     Affiliates other than those referred to above, and its and their employees
     and agents, as applicable, to so assign, to such other Party, without
     additional compensation, such right, title and interest in and to any
     Collaboration Results, as is necessary to fully effect the joint ownership
     provided for in the foregoing sentence.

     Assignment and transfer of all such Collaboration Results as contemplated
     by this Section 12.1 shall occur instantly and automatically upon the
     development, making, conception or reduction to practice of such
     Collaboration Results, as the case may be, and shall not require any
     further deeds or documents to be exchanged between the Parties.

12.2 Ownership of Development Results. AstraZeneca shall exclusively own all
     Development Results. Avanir shall promptly disclose to AstraZeneca in
     writing the development, making, conception or reduction to practice of any
     Development Results, and shall, and does hereby, assign, and shall cause
     its majority-owned subsidiaries (and its other Affiliates which are
     Affiliates both as of the Effective Date and at the relevant periods
     referred to above) and its and their employees and agents, as applicable
     and use its best reasonable efforts to cause its Affiliates other than
     those now mentioned and its and their employees and agents, as applicable,
     to so assign, to AstraZeneca, without additional compensation, such right,
     title and interest in and to any Development Results. Assignment and
     transfer of all such Development Results shall occur instantly and

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     automatically upon the development, making, conception or reduction to
     practice of such Development Results, as the case may be, and shall not
     require any further deeds or documents to be exchanged between the Parties.

12.3 AstraZeneca Improvements. AstraZeneca shall exclusively own all AstraZeneca
     Improvements and AstraZeneca Patents. Avanir shall promptly disclose to
     AstraZeneca in writing the development, making, conception or reduction to
     practice of any Results that constitute AstraZeneca Improvements, and
     shall, and does hereby, assign, and shall cause its Affiliates and its and
     their employees and agents, as applicable, to so assign, to AstraZeneca,
     without additional compensation, such right, title and interest in and to
     any such Results. Assignment and transfer of all such Results shall occur
     instantly and automatically upon the development, making, conception or
     reduction to practice of such Results, as the case may be, and shall not
     require any further deeds or documents to be exchanged between the Parties.

12.4 Improvements outside the Research Collaboration.

     12.4.1 Avanir shall without delay disclose to AstraZeneca any Licensed
          Improvements Controlled by Avanir or its majority-owned subsidiaries
          (or its other Affiliates that are Affiliates both as of the Effective
          Date and at all relevant times thereafter) and shall use its best
          reasonable efforts to obtain rights to so disclose to AstraZeneca any
          Licensed Improvements Controlled by any of its Affiliates other than
          those referred to above outside the scope of the Research
          Collaboration during any period in which AstraZeneca owes royalties to
          Avanir pursuant to Section 10.2 or 10.4 and provide AstraZeneca with
          all relevant Information and materials with respect to such Licensed
          Improvements. AstraZeneca shall have the right, at any time, to reject
          any such Licensed Improvement on written notice to Avanir, in which
          event, this Agreement shall cease to apply to such Licensed
          Improvement.

     12.4.2 All Licensed Improvements shall automatically be included within the
          scope of this Agreement, subject to AstraZeneca's right to reject any
          such Licensed Improvement pursuant to Section 12.4.1. Any Information
          with respect to such

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          Licensed Improvements that is not covered or claimed by a Patent and
          which is not generally known and is necessary or useful for the
          Exploitation of the Licensed Compounds or the Licensed Products shall
          be considered Licensed Know-How, and the Parties will add such
          Information to the Licensed Know-How Manual. Any Patents to the extent
          covering Licensed Improvements shall be considered Licensed Patents.

13   ADVERSE EVENT REPORTING

13.1 On or within sixty (60) days of the Effective Date, the Parties will enter
     into a safety agreement in the form of the agreement attached at Exhibit A
     (the "SAFETY AGREEMENT"). In the event of any inconsistency between the
     provisions of the Safety Agreement and the provisions of this Agreement,
     the provisions of this Agreement shall prevail.

14   CONFIDENTIALITY & NON-DISCLOSURE

14.1 General Obligations

     14.1.1 In this Agreement, "CONFIDENTIAL INFORMATION" shall, subject to
          Section 14.3, mean any and all data, results, know-how (including the
          Licensed Know-How), plans, business information and other Information,
          whether oral or in writing or in any other form, disclosed before, on
          or after the Effective Date by one Party to the other Party, including
          the terms of this Agreement. For the avoidance of doubt, the
          AstraZeneca Background Technologies and AstraZeneca Improvements shall
          be deemed to constitute Confidential Information proprietary to
          AstraZeneca. At all times during the term of this Agreement and for a
          period of *** years following termination or expiration hereof, each
          Party (the "RECEIVING PARTY") shall, and shall cause its officers,
          directors, employees, agents, Affiliates and Sublicensees to, keep
          confidential and not publish or otherwise disclose and not use,
          directly or indirectly, for any purpose, any Confidential Information
          provided to it by the

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          other Party (the "DISCLOSING Party"), except to the extent such
          disclosure or use is expressly permitted by the terms of this
          Agreement or is reasonably necessary for the performance of this
          Agreement.

     14.1.2 Avanir recognises that by reason of AstraZeneca's status as an
          exclusive licensee pursuant to the grants under Section 3.1,
          AstraZeneca has an interest in Avanir's retention in confidence of
          certain information of Avanir. Accordingly, until the expiration of
          AstraZeneca's exclusive position with respect to a Licensed Product or
          a Licensed Improvement under Section 3.7, or receipt of earlier
          written consent from AstraZeneca, Avanir shall, and shall cause its
          Affiliates and their respective officers, directors, employees and
          agents to, keep completely confidential, and not publish or otherwise
          disclose, and not use directly or indirectly for any purpose that
          would cause such publication or disclosure inconsistent with this
          Agreement, any such information relating to (a) such Licensed Product
          or Licensed Improvement, including the Licensed Compounds included
          therein and any Regulatory Documentation, including the Health
          Registration Approvals, with respect thereto, (b) the Collaboration
          Results relating thereto, or (c) the Exploitation of such Licensed
          Product or Licensed Improvement, including any development, sales or
          marketing plans therefore (the "ASTRAZENECA INFORMATION"), except to
          the extent (x) the AstraZeneca Information is in the public domain
          through no fault of Avanir, its Affiliates or any of their respective
          officers, directors, employees or agents, (y) such disclosure or use
          would be permitted under Section 14.2, or (z) such disclosure or use
          is otherwise expressly permitted by the terms of this Agreement or is
          reasonably necessary for the performance of this Agreement. For
          clarification, the disclosure by Avanir to AstraZeneca, or any of its
          Affiliates, or by AstraZeneca, or any of its Affiliates, to Avanir of
          AstraZeneca Information shall not cause such information to cease to
          be subject to the confidentiality provisions of this Section 14.1.

14.2 Permitted Disclosures. Each Party may disclose Confidential Information to
     the extent that such disclosure is:

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     14.2.1 made in response to a valid order of a court of competent
          jurisdiction or other competent authority; provided, however, that the
          Receiving Party shall first have given notice to the Disclosing Party
          and given the Disclosing Party a reasonable opportunity to quash any
          such order or obtain a protective order requiring that the
          Confidential Information and documents that are the subject of such
          order be held in confidence by such court or authority or, if
          disclosed, be used only for the purpose for which the order was
          issued; and provided further that if such order is not quashed or a
          protective order is not obtained, the Confidential Information
          disclosed in response to such court or governmental order shall be
          limited to that information that is legally required to be disclosed
          in response to such court or governmental order;

     14.2.2 made by the Receiving Party to a Health Authority as may be
          necessary or useful in connection with any filing, application or
          request for a Health Registration Approval; provided, however, that
          reasonable measures shall be taken to assure confidential treatment of
          such information, to the extent such protection is available;

     14.2.3 made by the Receiving Party to a patent authority as may be
          necessary or useful for purposes of obtaining or enforcing a Patent
          (consistent with the terms and conditions of Article 19); provided,
          however, that reasonable measures shall be taken to assure
          confidential treatment of such information, to the extent such
          protection is available;

     14.2.4 otherwise required by law; provided, however, that the Receiving
          Party shall (a) provide the Disclosing Party with reasonable advance
          notice of and an opportunity to comment on any such required
          disclosure to the extent practicable, (b) if requested by the
          Disclosing Party, seek confidential treatment with respect to any such
          disclosure to the extent available, and (c) use good faith efforts to
          incorporate the comments of the Disclosing Party in any such
          disclosure or request for confidential treatment; or

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     14.2.5 made by AstraZeneca or its Affiliates, Distributors or Sublicensees
          to Third Parties as may be necessary or useful in connection with the
          Exploitation of the Licensed Compounds, the Licensed Products or
          Improvements as contemplated by this Agreement, including
          subcontracting or sublicensing transactions in connection therewith.

     Notwithstanding the foregoing, in the event that either Party is required
     by Applicable Law or the requirements of a national securities exchange or
     another similar regulatory body to disclose this Agreement, in whole or in
     part, the Parties shall reasonably agree on a redacted version of this
     Agreement as necessary to protect the Confidential Information of the
     Parties prior to making such disclosure.

14.3 Exclusions. Notwithstanding the foregoing, Confidential Information shall
     not include any information that:

     14.3.1 is or hereafter becomes part of the public domain by public use,
          publication, general knowledge or the like through no wrongful act,
          fault or negligence on the part of the Receiving Party;

     14.3.2 can be demonstrated by documentation or other competent proof to
          have been in the Receiving Party's or its Affiliates' possession prior
          to disclosure by the Disclosing Party;

     14.3.3 is subsequently received by the Receiving Party or its Affiliates
          from a Third Party or Sublicensee without any obligations who is not
          bound by any obligation of confidentiality with respect to said
          information;

     14.3.4 is generally made available to Third Parties by the Disclosing Party
          without restriction on disclosure; or

     14.3.5 is independently developed by or for the Receiving Party or its
          Affiliates without reference to the Disclosing Party's Confidential
          Information.

     Specific aspects or details of Confidential Information shall not be deemed
     to be within the public domain or in the possession of the Receiving Party
     merely because the Confidential Information is embraced by more general
     information in the public domain

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     or in the possession of the Receiving Party. Further, any combination of
     Confidential Information shall not be considered in the public domain or in
     the possession of the Receiving Party merely because individual elements of
     such Confidential Information are in the public domain or in the possession
     of the Receiving Party unless the combination and its principles are in the
     public domain or in the possession of the Receiving Party.

14.4 Publications and Presentations. The Parties acknowledge that scientific
     publications must be strictly monitored to prevent any adverse effect from
     premature publication of Results. Accordingly, Avanir shall not publish,
     present or otherwise disclose any material related to the Exploitation of
     the Licensed Compounds, the Licensed Products or Improvements without the
     prior written consent of AstraZeneca.

14.5 Press Release. The Parties have agreed upon the content of a press release
     which shall be issued substantially in the form attached hereto as Schedule
     7, the release of which the Parties will coordinate in order to accomplish
     the same promptly upon execution and delivery of this Agreement. Except to
     the extent already disclosed in a press release or other public
     communication, no public announcement concerning this Agreement, its
     subject matter or the transactions described herein shall be made, either
     directly or indirectly, by Avanir or AstraZeneca or their respective
     Affiliates, except as may be legally required by applicable laws,
     regulations, judicial order, or required by stock exchange or quotation
     system rule without first obtaining the approval of the other Party and
     agreement upon the nature, text, and timing of such announcement, which
     approval and agreement shall not be unreasonably withheld or delayed. The
     Party desiring to make any such voluntary public announcement shall provide
     the other Party with a written copy of the proposed announcement in
     reasonably sufficient time prior to public release to allow such other
     Party to comment upon such announcement, prior to public release. In the
     case of press releases or other public communications legally required, or
     required by stock exchange or quotation system rule, to be made, the Party
     making such press release or public announcement shall provide to the other
     Party a copy of the proposed press release or public announcement in
     written or electronic form upon such advance notice as is practicable under
     the circumstances for the purpose of allowing the

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     notified Party to review and comment upon such press release or public
     announcement. Under such circumstances, the releasing Party shall not be
     obligated to delay making any such press release or public communication
     beyond the time when the same is required to be made in order to facilitate
     review and comment by the receiving Party.

14.6 Use of Name

     14.6.1 Neither Party shall mention or otherwise use the name, insignia,
          symbol, trademark, trade name or logotype of the other Party or its
          Affiliates in any publication, press release, promotional material or
          other form of publicity without the prior written consent of the other
          Party (which shall not be unreasonably withheld or delayed), except
          for those disclosures for which consent has previously been obtained.
          The restrictions imposed by this Section 14.6.1 shall not prohibit
          either Party from making any disclosure identifying the other Party
          that is required by Applicable Law or the requirements of a national
          securities exchange or another similar regulatory body, provided that
          any such disclosure shall be governed by this Article 14. Further, the
          restrictions imposed on each Party under this Section 14.6 are not
          intended, and shall not be construed, to prohibit a Party from
          identifying the other Party in its internal business communications,
          provided that any Confidential Information in such communications
          remains subject to this Article 14.

     14.6.2 Notwithstanding the foregoing, AstraZeneca and its Affiliates and
          Sublicensees shall have the right to use the name of Avanir and its
          Affiliates to the extent necessary or useful in connection with the
          Exploitation of the Licensed Compounds, Licensed Products and
          Improvements as contemplated by this Agreement, including
          subcontracting and sublicensing transactions in connection therewith.

15   TRADEMARKS

     AstraZeneca shall have the sole right to select Trademarks for the
     marketing and sale of the Licensed Products in the Territory. AstraZeneca
     shall own such Trademarks and all

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     rights and goodwill with respect thereto. Avanir shall not, and shall cause
     its majority-owned subsidiaries (and its other Affiliates that are
     Affiliates both as of the Effective Date and at all relevant times) to use
     its best reasonable efforts to cause its Affiliates other than those
     referred to above, not to use any trademark that is the same as or
     confusingly similar to, misleading or deceptive with respect to or that
     dilutes the Trademarks.

16   REPRESENTATIONS, WARRANTIES AND COVENANTS

16.1 Avanir represents, warrants to AstraZeneca as of the Effective Date that:

     16.1.1 Avanir is duly organized, validly existing and in good standing
          under the laws of the State of California, with full corporate power
          and authority to execute and deliver this Agreement and to perform its
          obligations hereunder

     16.1.2 This Agreement has been duly executed and delivered by Avanir and
          constitutes the valid and binding obligation of Avanir, enforceable
          against Avanir in accordance with its terms, subject to bankruptcy,
          insolvency or similar laws of general application affecting the rights
          of creditors, and subject to equitable principles limiting rights to
          specific performance or other equitable remedies. The execution,
          delivery and performance of this Agreement have been duly authorized
          by all necessary action on the part of Avanir, its officers and
          directors on behalf of Avanir and no other corporate proceedings on
          the part of Avanir are necessary to authorize such execution, delivery
          and performance.

     16.1.3 Avanir, is the sole and exclusive owner of the entire right, title
          and interest in the Licensed Patents and to its Knowledge the Licensed
          Know-How, and is entitled to grant the licences herein. Avanir has not
          placed, and to its Knowledge there does not exist, upon the Licensed
          Patents and Licensed Know-How any encumbrance or lien. No claim has
          been made to Avanir of ownership by any Third Party of any right or
          interest in or to the Licensed Patents and Licensed Know-How. The
          granting of the licenses to AstraZeneca hereunder does not violate any
          right known to Avanir of any Third Party and, and to its Knowledge,
          Avanir has

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          obtained all necessary consents from Third Parties in order to allow
          it to enter into its obligations under this Agreement.

     16.1.4 The Licensed Patents listed on Schedule 4 represent all Patents
          within Avanir and its Affiliates' Control relating to the AVP 26452
          Compound, the AVP 26452 Product, and the Back-Up Compound(s) as of the
          Effective Date. The Licensed Patents have been filed and maintained
          properly and correctly and all applicable fees have been paid on or
          before the due date for payment. In respect of the pending United
          States patent applications included in the Licensed Patents, Avanir
          has presented all relevant prior art of which it and the inventors are
          aware to the United States Patent and Trademark Office.

     16.1.5 To the Knowledge of Avanir and its Affiliates, the Licensed Patents
          and the Licensed Know-How existing as of the Effective Date are
          subsisting and are not invalid or unenforceable, in whole or in part.

     16.1.6 To the Knowledge of Avanir and its Affiliates, the disclosing,
          copying, making, assigning, licensing or the Exploitation pursuant to
          this Agreement of the Licensed Patents or Licensed Know-How hereunder
          will not infringe or conflict with any Patent or other IP Protection
          Right of any Person. To the Knowledge of Avanir and its Affiliates,
          the conception, development and reduction to practice of the Licensed
          Patents and Licensed Know-How existing as of the Effective Date have
          not constituted or involved the misappropriation of trade secrets or
          other rights or property of any Person.

     16.1.7 As of the Effective Date, to the Knowledge of Avanir and its
          Affiliates, there is no actual infringement or threatened infringement
          of the Licensed Patents by any Person. Furthermore, there is no claim,
          litigation, action, suit, proceeding investigation, arbitration
          proceedings or other proceedings pending or, to the Knowledge of
          Avanir and its Affiliates, threatened affecting, in whole or in part,
          the Licensed Patents or Licensed Know-How at law, in equity or
          otherwise, in, before, or by, any court, arbitration tribunal, or
          governmental authority, and there is not currently outstanding any
          unsatisfied judgment or outstanding order,

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          injunction, decree, stipulation or award (whether rendered by a court,
          an administrative agency or by an arbitrator) domestic or foreign, or
          arbitrator relating, in whole or in part, against any of the Licensed
          Patents or the Licensed Know-How.

     16.1.8 To the Knowledge of Avanir and its Affiliates the Licensed Know-How
          has been kept confidential or has been disclosed to Third Parties only
          under terms of confidentiality. To the Knowledge of Avanir and its
          Affiliates no breach of such confidentiality has been committed by any
          Third Party. For the avoidance of doubt, the chemical structures under
          the Licensed Patents have not, other than to the extent they have been
          part of a patent application that is in the public domain, been
          disclosed to any Third Party.

     16.1.9 Execution of this Agreement and consummation of the transactions
          contemplated hereby and thereby will not: (i) result in the violation
          of or conflict with any of the terms and provisions of the articles of
          incorporation or by-laws of Avanir; (ii) result in a violation or
          breach of, or constitute (with or without due notice or lapse of time
          or both) a default (or give rise to any right of termination,
          modification, cancellation or acceleration or loss of material
          benefits) under, any of the terms, conditions or provisions of any
          note, bond, mortgage, indenture, contract, agreement, permit, license,
          lease, purchase order, sales order, arrangement or other commitment or
          obligation to which Avanir is a Party; or (iii) violate any order,
          writ, injunction, decree, statute, treaty, rule or regulation
          applicable to Avanir, except such violations, breaches or defaults
          with respect to clauses (ii) and (iii) above which would not have a
          material adverse effect, either alone or in the aggregate.

     16.1.10 Avanir has not been debarred and is not subject to debarment
          pursuant to Section 306 of the United States Federal Food, Drug, and
          Cosmetic Act.

     16.1.11 Avanir shall obtain from each of its Affiliates, sublicensees,
          employees and agents rights to any and all Information that relate to
          the Licensed Compounds or Licensed Products, such that AstraZeneca
          shall, by virtue of this Agreement,

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          receive from Avanir, without payments beyond those required by
          Articles 9 and 10, the licences and other rights granted to
          AstraZeneca hereunder.

16.2 AstraZeneca represents and warrants to Avanir as of the Effective Date
     that:

     16.2.1 AstraZeneca is duly organized, validly existing and in good standing
          under the laws of England with full power and authority to execute and
          deliver this Agreement and to perform its obligations hereunder.

     16.2.2 AstraZeneca represents and warrants to Avanir that this Agreement
          has been duly executed and delivered by AstraZeneca and constitutes
          the valid and binding obligation of AstraZeneca, enforceable against
          AstraZeneca in accordance with its terms. The execution, delivery and
          performance of this Agreement have been duly authorized by all
          necessary action on the part of AstraZeneca, its officers and
          directors on behalf of AstraZeneca.

     16.2.3 AstraZeneca has not been debarred and is not subject to debarment.

16.3 Avanir hereby covenants to AstraZeneca that (i) it will assign to
     AstraZeneca all of its rights, titles and interests in and to all
     Regulatory Documentation, including, to the extent permitted by Applicable
     Law, all Health Registration Approvals, Controlled by Avanir as of the
     Effective Date and from time to time during the term of this Agreement;
     (ii) it will duly execute and deliver, or cause to be duly executed and
     delivered, such instruments and shall do and cause to be done such acts and
     things, including the filing of such assignments, agreements, documents and
     instruments, as may be necessary under, or as AstraZeneca may reasonably
     request in connection with, or to carry out more effectively the purpose to
     better assure and confirm unto AstraZeneca its rights under Section
     16.3(i).; (iii) it will not enter into any agreement, whether written or
     oral, inconsistent with the rights and licenses granted hereunder, and (iv)
     to its Knowledge it will not use in any capacity, in connection with the
     services to be performed under this Agreement, any Person who has been
     debarred pursuant to Section 306 of the United States Federal Food, Drug,
     and Cosmetic Act, or who is the subject of a conviction described in such
     section. Avanir agrees to inform AstraZeneca in writing promptly if it or
     any Person who is performing services hereunder is debarred or is the
     subject of a

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     conviction described in Section 306, or if any action, suit, claim,
     investigation or legal or administrative proceeding is pending or, to the
     best of Avanir's or its Affiliates' Knowledge, is threatened, relating to
     the debarment or conviction of Avanir or any Person performing services
     hereunder.

16.4 AstraZeneca hereby covenants to Avanir that to its Knowledge it will not
     use in any capacity, in connection with the services to be performed under
     this Agreement, any Person who has been debarred pursuant to Section 306 of
     the United States Federal Food, Drug, and Cosmetic Act, or who is the
     subject of a conviction described in such section. AstraZeneca agrees to
     inform Avanir in writing promptly if it or any Person who is performing
     services hereunder is debarred or is the subject of a conviction described
     in Section 306, or if any action, suit, claim, investigation or legal or
     administrative proceeding is pending or, to AstraZeneca's or its
     Affiliates' Knowledge, is threatened, relating to the debarment or
     conviction of AstraZeneca or any Person performing services hereunder.

17   INDEMNITY

17.1 Indemnification of Avanir In addition to any other remedy available to
     Avanir, AstraZeneca shall indemnify, defend and hold harmless Avanir, its
     Affiliates and its and their respective former and current directors,
     officers and employees in full and on demand, from and against any and all
     Losses incurred by them to the extent resulting from or arising out of or
     in connection with any claims made or suits brought by a Sublicensee or
     Third Party (collectively, "THIRD PARTY CLAIMS") against Avanir, its
     Affiliates or its or their respective former and current directors,
     officers or employees that arise out of or result from:

          (a)  the development, manufacture, use, sale, storage or handling of a
               Licensed Compound or Licensed Product by AstraZeneca or its
               Affiliates or their representatives, agents, licensees,
               Sublicensees or subcontractors, or any actual or alleged
               violation of law resulting therefrom (with the exception of
               Losses based on infringement or misappropriation of intellectual
               property rights);

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          (b)  the breach by AstraZeneca, its Affiliates or Sublicensees of any
               of their material obligations, covenants, representations or
               warranties set forth in this Agreement; or

          (c)  the use, storage or handling by any Third Party of a Licensed
               Compound or a Licensed Product, the direct or indirect source of
               which is AstraZeneca, its Affiliates or Sublicensees;

     provided that the foregoing indemnification shall not apply to any Loss to
     the extent such Loss is caused by the breach of this Agreement or the
     negligence or wilful misconduct of Avanir or its Affiliates and their
     current or former employees, officers and directors.

17.2 Indemnification of AstraZeneca In addition to any other remedy available to
     AstraZeneca, Avanir shall indemnify, defend and hold harmless AstraZeneca,
     its Affiliates, and Sublicensees and its and their respective former and
     current directors, officers and employees in full and on demand, from and
     against any and all Losses incurred by them to the extent resulting from or
     arising out of or in connection with any Third Party Claims against
     AstraZeneca, its Affiliates or its or their respective former or current
     directors, officers or employees that arise out of or result from:

          (a)  negligence or wilful misconduct by Avanir or its Affiliates
               concerning their participation in the Research Collaboration or
               in performing consulting services or conducting IND studies under
               this Agreement; or

          (b)  the breach by Avanir of any of its material obligations,
               covenants, representations or warranties set forth in this
               Agreement; or

          (c)  Avanir's handling of the Licensed Compounds under the Research
               Collaboration; or

          (d)  Exploitation of any Licensed Compounds or Licensed Products by
               Avanir, its Affiliates or sublicensees after a termination by
               AstraZeneca pursuant to Section 21.3, 21.4 or 21.6 or by Avanir
               pursuant to Section 21.5;

     provided that the foregoing indemnification shall not apply to any Loss to
     the extent such Loss is caused by the breach of this Agreement or the
     negligence or wilful misconduct of

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     AstraZeneca, its Affiliates, or their Sublicensees and their current or
     former employees, officers and directors.

17.3 Notice of Claim An Indemnified Party shall give the Indemnifying Party
     prompt written notice of any Loss or discovery of fact upon which such
     Indemnified Party intends to base a request for indemnification under
     Section 17.1 or 17.2 (an "INDEMNIFICATION CLAIM NOTICE"). In no event shall
     the Indemnifying Party be liable for any Loss that results from any delay
     in providing the Indemnification Claim Notice. Each Indemnification Claim
     Notice shall contain a description of the claim and the nature and amount
     of the Loss claimed (to the extent that the nature and amount of such Loss
     is known at such time). The Indemnified Party shall furnish promptly to the
     Indemnifying Party copies of all papers and official documents received in
     respect of any such Loss. For the avoidance of doubt, all indemnification
     claims in respect of a Party, its Affiliates or their respective current or
     former directors, officers, employees and agents (each, an "INDEMNITEE")
     shall be made solely by such Party to this Agreement.

17.4 Indemnification Procedures. The obligations of an Indemnifying Party under
     this Article 17 shall be governed by and contingent upon the following:

     17.4.1 Assumption of Defence. At its option, the Indemnifying Party may
          assume the defence of any Third Party Claim by giving written notice
          to the Indemnified Party within fourteen (14) days after the
          Indemnifying Party's receipt of an Indemnification Claim Notice. The
          assumption of the defence of a Third Party Claim by the Indemnifying
          Party shall not be construed as an acknowledgement that the
          Indemnifying Party is liable to indemnify any Indemnitee in respect of
          the Third Party Claim, nor shall it constitute a waiver by the
          Indemnifying Party of any defences it may assert against any
          Indemnified Party's claim for indemnification.

     17.4.2 Control of Defence. Upon the assumption of the defence of a Third
          Party Claim by the Indemnifying Party:

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          (a)  the Indemnifying Party may appoint as lead counsel in the defence
               of the Third Party Claim any legal counsel selected by the
               Indemnifying Party, which shall be reasonably acceptable to the
               Indemnified Party, and

          (b)  the Indemnifying Party shall not be liable to the Indemnified
               Party for any legal expenses subsequently incurred by such
               Indemnified Party or any Indemnitee in connection with the
               analysis, defence or settlement of the Third Party Claim, except
               as expressly provided in Section 17.4.3. In the event that it is
               ultimately determined that the Indemnifying Party is not
               obligated to indemnify, defend or hold harmless an Indemnitee
               from and against the Third Party Claim, the Indemnified Party
               shall reimburse the Indemnifying Party for any and all costs and
               expenses (including lawyers' fees and costs of suit) and any Loss
               incurred by the Indemnifying Party in its defence of the Third
               Party Claim with respect to such Indemnified Party or Indemnitee.

     17.4.3 Right to Participate in Defence. Without limiting Section 17.4.1
          or17.4.2, any Indemnitee shall be entitled to participate in, but not
          control, the defence of a Third Party Claim and to retain counsel of
          its choice for such purpose; provided, however, that such retention
          shall be at the Indemnitee's own expense unless, (a) the Indemnifying
          Party has failed to assume the defence and retain counsel in
          accordance with Section 17.4.1 (in which case the Indemnified Party
          shall control the defence), or (b) the interests of the Indemnitee and
          the Indemnifying Party with respect to such Third Party Claim are
          sufficiently adverse to prohibit the representation by the same
          counsel of both parties under Applicable Law, ethical rules or
          equitable principles.

     17.4.4 Settlement. With respect to Losses in connection with Third Party
          Claims, where the Indemnifying Party has assumed the defence of a
          Third Party Claim in accordance with Section 17.4.1, (i) the
          Indemnifying Party shall have authority to consent to the entry of any
          judgement, enter into any settlement or otherwise dispose of such
          Losses, provided that it obtains the prior written consent of the

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          Indemnified Party which consent shall not be unreasonably withheld or
          delayed and (ii) no Indemnified Party or Indemnitee shall admit any
          liability with respect to, or settle, compromise or discharge, any
          Third Party Claim without the prior written consent of the
          Indemnifying Party, which consent shall not be unreasonably withheld
          or delayed.

     17.4.5 Cooperation. If the Indemnifying Party chooses to defend or
          prosecute any Third Party Claim, the Indemnified Party shall, and
          shall cause each other Indemnitee to, cooperate in the defence or
          prosecution thereof and shall furnish such records, information and
          testimony, provide such witnesses and attend such conferences,
          discovery proceedings, hearings, trials and appeals as may be
          reasonably requested in connection therewith. Such cooperation shall
          include access during normal business hours by the Indemnifying Party
          to, and reasonable retention by the Indemnified Party of, records and
          information that are reasonably relevant to such Third Party Claim,
          and making the Indemnified Party, the Indemnitees and its and their
          employees and agents available on a mutually convenient basis to
          provide additional information and explanation of any records or
          information provided, and the Indemnifying Party shall reimburse the
          Indemnified Party for all of its related reasonable out-of-pocket
          expenses.

     17.4.6 Expenses. Except as expressly provided above, the reasonable and
          verifiable costs and expenses, including fees and disbursements of
          counsel, incurred by the Indemnified Party in connection with any
          claim shall be reimbursed on a Calendar Quarter basis by the
          Indemnifying Party, without prejudice to the Indemnifying Party's
          right to contest the Indemnified Party's right to indemnification and
          subject to refund in the event the Indemnifying Party is ultimately
          held not to be obligated to indemnify the Indemnified Party.

17.5 Limitation of Liability. Neither Party shall be liable to the other for
     consequential, indirect or punitive damages. The foregoing limitation is
     not intended to limit a Party's obligations under Section 17.1 or Section
     17.2. For the avoidance of doubt, no Party can recover from the other Party
     more than once for a single cause of action under an

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     indemnity granted by an indemnifying Party pursuant to this Agreement. The
     foregoing sentence shall not be construed to preclude recovery in respect
     of multiple claims arising from a single event or series of events. Neither
     Party shall have liability with respect to any breach of any of such
     Party's representations and warranties under this Agreement for any
     individual item where the Loss relating thereto is less than *** U.S.
     Dollars ($***) but when a Loss exceeds such amount then the liable Party
     shall be liable for the entire amount of the Losses. The foregoing shall
     not be construed to limit liability pursuant to Section 17.1 or Section
     17.2. Each Party shall take and shall cause its Affiliates to take all
     reasonable steps to mitigate any Loss upon becoming aware of any event
     which would reasonably be expected to, or does, give rise thereto,
     including incurring costs only to the minimum extent necessary to remedy a
     breach that gives rise to the Loss. EXCEPT AS EXPRESSLY SET FORTH IN THIS
     AGREEMENT, AVANIR HEREBY EXPRESSLY DISCLAIMS ANY AND ALL WARRANTIES,
     WHETHER EXPRESS OR IMPLIED, AND FURTHER DISCLAIMS ANY EXPRESS OR IMPLIED
     WARRANTIES OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE OF ANY
     ITEM LICENSED TO ASTRAZENECA PURSUANT TO THIS AGREEMENT.

18   MAINTENANCE AND PROSECUTION OF PATENTS

18.1 Licensed Patents. AstraZeneca, through counsel of its choosing that is
     reasonably acceptable to Avanir, *** shall be responsible for obtaining,
     prosecuting (including any interferences, reissue proceedings and
     re-examinations), and maintaining throughout the world the Licensed
     Patents. In this regard, AstraZeneca shall (a) file and prosecute Patent
     applications to secure Patent rights for the Licensed Patents and such
     other patentable Licensed Know-How in the Major Markets and such other
     countries as determined by AstraZeneca or as mutually agreed by AstraZeneca
     and Avanir; and (b) upon issuance, maintain such Patents in full force in
     such countries. AstraZeneca shall regularly confer with Avanir regarding
     strategies and tactics for the conduct of the

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     foregoing activities. AstraZeneca shall give due regard to Avanir's views
     in the conduct of the foregoing activities; and in particular to material
     suggestions, which may be reasonably implemented provided that such
     suggestions are otherwise consistent with AstraZeneca's direction.

     Notwithstanding what is stated in the first sentence in the immediately
     preceding paragraph AstraZeneca shall not prior to the *** select counsel
     for obtaining, prosecuting and maintaining the Licensed Patents different
     from the counsel that was used for these purposes by Avanir immediately
     prior to the Effective Date unless such counsel has a conflict of interest
     in relation to AstraZeneca's cardiovascular business or there are other
     similar significant obstacles using such counsel. Upon AstraZeneca
     selecting a different counsel the Parties will endeavour to establish
     procedures to capture the experience and knowledge in the possession of
     such Avanir's former counsel with respect to the Licensed Patents and the
     prosecution thereof.

18.2 Election not to Prosecute. If AstraZeneca elects not to pursue or continue
     the filing, prosecution (including any interferences, reissue proceedings
     and re-examinations) or maintenance of a Licensed Patent, a Joint Patent or
     an AstraZeneca Patent in a particular country, AstraZeneca shall so notify
     Avanir promptly in writing and in good time to enable Avanir to meet any
     deadlines by which an action must be taken to establish or preserve any
     such rights in such Licensed Patent, such Joint Patent or such AstraZeneca
     Patent in such country. Upon receipt of any such notice by AstraZeneca or
     if, at any time, AstraZeneca fails to initiate any such action within ***
     after a request by Avanir that it do so (or, if after initiating any
     requested action, AstraZeneca at any time thereafter fails to diligently
     pursue such action), with the consent of AstraZeneca, not to be
     unreasonably withheld or notice whether consent has been given unreasonably
     delayed, Avanir shall have the right, but not the obligation, to pursue the
     filing or registration, or support the continued prosecution or
     maintenance, of such Licensed Patent, Joint Patent

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     or an AstraZeneca Patent at its expense in such country. For the avoidance
     of doubt, if Valid Claims issue as a result of such activity, the
     applicable royalty rate to be paid in such jurisdiction shall be that
     applied to Valid Claims unless AstraZeneca at its discretion rejects such
     Valid Claim, in which case the licence granted hereunder shall not cover
     such Valid Claim and AstraZeneca shall have no rights under such Valid
     Claim.

18.3 Collaboration Results, Joint Patents and AstraZeneca Patents. AstraZeneca,
     through counsel of its choosing that is reasonably acceptable to Avanir,
     *** shall be responsible for obtaining, prosecuting (including any
     interferences, reissue proceedings and re-examinations), and maintaining
     throughout the world the Joint Patents and the AstraZeneca Patents in its
     reasonable discretion. In this regard, AstraZeneca shall (a) file and
     prosecute Patent applications to secure Patent rights for the Joint
     Patents, the AstraZeneca Patents in the Major Markets and such other
     countries as determined by AstraZeneca or as mutually agreed by AstraZeneca
     and Avanir; and (b) upon issuance, maintain such Patents in full force in
     such countries. AstraZeneca shall regularly confer with Avanir regarding
     strategies and tactics for the conduct of the foregoing activities.
     AstraZeneca shall give due regard to Avanir's views in the conduct of the
     foregoing activities; and in particular to material suggestions, which may
     be reasonably implemented provided that such suggestions are otherwise
     consistent with AstraZeneca's direction.

     None of AstraZeneca, Avanir or any of their respective Affiliates or
     Sublicensees shall Exploit any Joint Patent or Collaboration Results
     outside the scope of this Agreement without the consent of the other Party,
     and Avanir shall not assign, pledge, encumber or otherwise transfer any of
     its rights in any Collaboration Results or Joint Patents without
     AstraZeneca's prior written consent.

18.4 Cooperation

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     18.4.1 Each Party shall, and shall cause its Affiliates to, assist and
          cooperate with the other Party, as such other Party may reasonably
          request from time to time in connection with its activities under
          Sections 18.1 and 18.3. Each Party shall keep the other Party
          currently informed of all steps to be taken in the preparation and
          prosecution of all applications filed by such first Party (the
          "PROSECUTING PARTY") according to Sections 18.1 and Section 18.3 and
          shall furnish the non-Prosecuting Party with copies of such
          applications for Patents, amendments thereto and other related
          correspondence to and from patent offices, and, to the extent
          reasonably practicable, permit the non-Prosecuting Party an
          opportunity to offer its comments thereon before the Prosecuting Party
          makes a submission to a patent office which could materially affect
          the scope or validity of the patent coverage that may result. The
          non-Prosecuting Party shall offer its comments, if any, promptly, but
          in no event shall the Prosecuting Party be required to delay any such
          submission.

     18.4.2 The Prosecuting Party shall keep the non-Prosecuting Party apprised
          of any activities related thereto by providing the other Party (i)
          with a draft of new applications and foreign filing texts at least ***
          before the intended filing; (ii) promptly with copies of all official
          actions, amendments and responses, which affect the scope of any
          claims; (iii) with foreseen amendments and responses to official
          actions which affect the scope of any claim at least *** before the
          action due date although it is expressly recognised that time-lines
          now stated are indicative only and shall not be binding on the
          Prosecuting Party.

     18.4.3 Other than reasonably considering Avanir's comments, AstraZeneca or
          its Affiliates shall have sole discretion with respect to the
          preparation, filing, prosecution and maintenance of the Licensed
          Patents, the Joint Patents and the AstraZeneca Patents.

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     18.4.4 The non-Prosecuting Party undertakes at the reasonable request of
          the Prosecuting Party and at the Prosecuting Party's expense for the
          non-Prosecuting Party's out-of-pocket costs to sign, or have signed,
          any and all documents necessary in connection with the filing,
          prosecution, maintenance, extension and enforcement of the Licensed
          Patents, the Joint Patents and the AstraZeneca Patents, as the case
          may be, and to take such other necessary actions as the Parties or
          their Affiliates may reasonably request from each other in connection
          with the Licensed Patents, the Joint Patents and the AstraZeneca
          Patents.

     18.4.5 Upon the request by a Party, to be put no more frequent than every
          *** starting *** of the anniversary of the Effective Date, a Party
          shall update the other on the status of all filings for Licensed
          Patents, Joint Patents and AstraZeneca Patents including information
          on the country particulars, filing status and other information that
          such first Party may find relevant.

19   ENFORCEMENT OF PATENTS

19.1 Rights and Procedures. In the event that either Party supposes that a Third
     Party or Sublicensee may be infringing any of the Licensed Patents, Joint
     Patents or AstraZeneca Patents, such Party shall promptly notify the other
     Party in writing, identifying the alleged infringer and the alleged
     infringement complained of and furnishing the information upon which such
     determination is based. AstraZeneca shall be entitled, in its sole
     discretion but after notifying Avanir (if time permits), through counsel of
     its choosing, to take any measures it deems appropriate to stop such
     infringing activities by such Third Party or Sublicensee in any part of the
     Territory or to grant to the infringing Third Party or Sublicensee adequate
     rights and licences necessary for continuing such activities in the
     Territory. Upon reasonable request by AstraZeneca, Avanir shall give
     AstraZeneca all reasonable information and assistance, including allowing
     AstraZeneca access to Avanir's files and documents and to Avanir's
     personnel who may have

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     possession of relevant information and, if necessary for AstraZeneca to
     prosecute any legal action, joining in the legal action as a party at its
     own expense. In the event AstraZeneca fails within *** following notice of
     such infringement, or earlier notifies Avanir in writing of its intent not,
     to take commercially appropriate steps to remove any infringement of any
     Licensed Patent, Joint Patent or AstraZeneca Patent that is likely to have
     a material adverse effect on the sale of the Licensed Product, and
     AstraZeneca has not granted the infringing Third Party or Sublicensee
     rights and licences to continue its otherwise infringing activities, Avanir
     shall have the right to do so at Avanir's expense; provided, however, that
     if AstraZeneca has commenced negotiations with an alleged infringer for
     discontinuance of such infringement within such *** period, AstraZeneca
     shall have an additional *** to conclude its negotiations before Avanir may
     bring suit for such infringement. Upon reasonable request by Avanir and at
     Avanir's cost and expense, AstraZeneca shall give Avanir all reasonable
     information and assistance in connection with such suit for infringement.

19.2 Notwithstanding what is stated in Section 19.1, Avanir shall within ***
     advise AstraZeneca of receipt of any notice of (a) any certification filed
     under the U.S. "Drug Price Competition and Patent Term Restoration Act" of
     1984 (21 United States Code Section 355(b)(2)(A)(iv) or (j)(2)(A)(vii)(IV))
     ("ANDA ACT") claiming that any Licensed Patent, Joint Patent or AstraZeneca
     Patent is invalid or unenforceable or claiming that the Licensed Patents,
     Joint Patents or AstraZeneca Patents will not be infringed by the
     Manufacture, use, marketing or sale of a product for which an application
     under the ANDA ACT is filed, or (b) any equivalent or similar certification
     or notice in any other jurisdiction. The Parties' rights and obligations
     with respect to any legal action as a result of such certification shall be
     as set forth in this Article 19, provided that within *** of such notice
     AstraZeneca shall notify Avanir as to whether or not it elects to prosecute
     such infringement.

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19.3 Recovery. Any amounts recovered by either Party pursuant to Section 19.1,
     whether by settlement or judgment, shall be used to reimburse the Parties
     for their reasonable costs and expenses in making such recovery (which
     amounts shall be allocated pro rata if insufficient to cover the totality
     of such expenses), with any remainder being retained by or paid to
     AstraZeneca and, to the extent attributable to lost sales of Licensed
     Products, being deemed "***" for which AstraZeneca shall pay Avanir any
     royalties that may be owed with respect to such ***. The Party pursuing any
     action under Section 19.1 will bear all payments awarded against or agreed
     to be paid by such Party pursuant to such action, including any costs or
     expenses incurred that exceed the amounts recovered by such Party, provided
     that AstraZeneca shall have the right to offset *** percent (***%) of such
     amounts (including such costs and expenses) against the milestone payments
     and royalties payable under Article 10; and provided further that no
     royalty payment when due, regardless of the amount or number of credits
     available to AstraZeneca in accordance with this Agreement, shall be
     reduced by more than *** percent (***%) in any Calendar Quarter. Credits
     not exhausted in any Calendar Quarter may be carried into future Calendar
     Quarters subject to the foregoing sentence.

20   POTENTIAL THIRD PARTY RIGHTS

20.1 Third Party Licences. If, in the opinion of AstraZeneca, the Exploitation
     of the Licensed Compounds or Licensed Products by AstraZeneca, its
     Affiliates or any of their Sublicensees infringes or misappropriates any
     Patent or any IP Protection Right of a Third Party in any country, such
     that AstraZeneca or any of its Affiliates, Distributors or Sublicensees, in
     AstraZeneca's sole opinion, cannot Exploit the Licensed Compounds or the
     Licensed Products in such country without infringing the Patent or IP
     Protection Rights of such Third Party (a "TRIGGERING EVENT"), then,
     AstraZeneca shall have the first right, but not the obligation, through
     counsel of its choosing, to negotiate and obtain a licence from such Third
     Party as reasonably necessary for AstraZeneca and its Affiliates

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     and Sublicensees to Exploit the Licensed Compounds and Licensed Products in
     such country. Nothing contained in this Section 20.1 shall be construed to
     limit AstraZeneca's right to terminate this Agreement pursuant to Section
     21.4.

20.2 Invalidity or Unenforceability Defences or Actions

     20.2.1 In the event that a Third Party or Sublicensee asserts, as a defence
          or as a counterclaim in any infringement action under Section 19.1,
          that any Licensed Patent, Joint Patent or AstraZeneca Patent is
          invalid or unenforceable, then the Party pursuing such infringement
          action shall promptly give written notice to the other Party.
          AstraZeneca shall have the first right, but not the obligation,
          through counsel of its choosing, to respond to such defence or defend
          against such counterclaim (as applicable), including the right to
          settle or otherwise compromise such claim. If AstraZeneca notifies
          Avanir in writing that it does not wish to respond to such defence or
          defend against, or settle, such counterclaim (as applicable), Avanir
          shall, at its sole cost and expense, have the right to respond to such
          defence or defend against such counterclaim (as applicable); provided,
          however, that Avanir shall obtain the written consent of AstraZeneca
          prior to ceasing to defend, settling or otherwise compromising such
          defence or counterclaim.

     20.2.2 Similarly, if a Third Party or Sublicensee asserts, in a declaratory
          judgment action or similar action or claim filed by such Third Party
          or Sublicensee, that any Licensed Patent, Joint Patent or AstraZeneca
          Patent is invalid or unenforceable, then the Party first becoming
          aware of such action or claim shall promptly give written notice to
          the other Party. AstraZeneca shall have the first right, but not the
          obligation, through counsel of its choosing, to defend against such
          action or claim, including the right to settle or otherwise compromise
          such claim. If AstraZeneca notifies Avanir in writing that it does not
          wish to respond to or defend against or settle such action or claim,
          Avanir shall, at its sole cost and expense, have the right to defend
          against such action or claim; provided, however,

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          that Avanir shall obtain the written consent of AstraZeneca prior to
          ceasing to defend, settling or otherwise compromising any such action
          or claim.

20.3 Third Party Litigation. In the event of any actual or threatened suit
     against Avanir, AstraZeneca or its Affiliates, Sublicensees, Distributors
     or customers alleging that the Exploitation of Licensed Compounds or
     Licensed Products or that the Exploitation of a Licensed Patent, Joint
     Patents, AstraZeneca Patent, the Licensed Know-How, the Collaboration
     Results, or any part thereof by or on behalf of AstraZeneca under this
     Agreement infringes the Patent or IP Protection Rights of any Person (an
     "INFRINGEMENT SUIT"), the Party first becoming aware of such Infringement
     Suit shall promptly give written notice to the other Party. AstraZeneca
     shall have the first right, but not the obligation, through counsel of its
     choosing, to assume direction and control of the defence of claims arising
     therefrom (including the right to settle such claims at its sole
     discretion). If AstraZeneca notifies Avanir in writing that it does not
     wish to assume such direction and control, Avanir shall have the right, but
     not the obligation to, at its sole cost and expense, defend against such
     claims; provided, however, that Avanir shall obtain the written consent of
     AstraZeneca prior to ceasing to defend, settling or otherwise compromising
     such claims.

20.4 Cooperation. Avanir will provide to AstraZeneca all reasonable assistance
     requested by AstraZeneca in connection with any action, claim or suit under
     Section 20.2 or 20.3, including allowing AstraZeneca access to Avanir's
     files and documents and to Avanir's personnel who may have possession of
     relevant information. In particular Avanir will promptly make available to
     AstraZeneca, ***, all information in its possession or control that it is
     aware will assist AstraZeneca in responding to any such action, claim or
     suit under Section 20.2 or 20.3.

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21   TERM AND TERMINATION

21.1 Term. This Agreement shall become effective on the Effective Date and shall
     continue in full force and effect, unless earlier terminated in accordance
     with this Article 21, during the Collaboration Term and thereafter for as
     long as AstraZeneca is pursuing pre-clinical research or other activities
     or clinical development of one or more Licensed Compounds or
     commercialising Licensed Products for which royalties are owed to Avanir
     pursuant to Article 10.

21.2 Collaboration Term. The Collaboration Term shall commence on the Effective
     Date and, unless the Agreement is terminated pursuant to Sections 21.3,
     21.4, 21.5, 21.6 or 21.9 or the Research Collaboration is terminated by
     AstraZeneca pursuant to Section 5.2, 21.6 or 21.9, continue until the later
     of (a) the expiration of the *** Collaboration Year, and (b) such date
     until which the Parties may have agreed that AstraZeneca shall provide
     funding to Avanir in accordance with Section 9.1.

21.3 Termination by AstraZeneca. AstraZeneca shall have the right, in its sole
     discretion, after the *** to terminate this Agreement in its entirety or
     with respect to one or more countries in the Territory upon *** prior
     written notice; provided, however, that during the Collaboration Term such
     termination shall not take effect until *** of the date of such notice or
     upon the date when the Collaboration Term expires (provided always that
     such termination does never take effect prior to the expiration of the ***
     notice period), whichever is the earlier.

     In the event that AstraZeneca terminates this Agreement pursuant to this
     Section 21.3 before the end of the Collaboration Term, AstraZeneca shall
     make a lump sum payment to Avanir to compensate Avanir for such early
     termination in an amount equal to the forecasted FTE funding due to Avanir
     pursuant to Article 9.1 above for the *** following immediately after the
     date of AstraZeneca providing notice of termination; provided,

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     however, that AstraZeneca shall have no obligation to make such payment in
     the event it terminates this Agreement pursuant to Section 21.5, 21.6 or
     21.9.

21.4 Termination for Infringement of Third Party Rights.

     21.4.1 If a Triggering Event occurs with respect to a country, AstraZeneca
          shall have the right upon written notice to Avanir to terminate this
          Agreement with respect to such country if at *** (a) AstraZeneca is
          unable to obtain such a licence on commercially reasonable terms or
          (b) AstraZeneca in good faith believes that negotiation with a Third
          Party pursuant to Article 20 with respect to such country is not
          likely to result in a commercially reasonable agreement; provided,
          however, that AstraZeneca shall have the right to terminate this
          Agreement with respect to all of Europe if such country is in Europe
          and AstraZeneca shall have the right to terminate this Agreement in
          its entirety if such country is or is in a Major Market.

     21.4.2 If a Third Party institutes an Infringement Suit with respect to a
          country, AstraZeneca shall have the right upon written notice to
          Avanir to terminate this Agreement with respect to such country if (a)
          within *** of filing, such Infringement Suit is not settled, dismissed
          or otherwise disposed of on terms reasonably acceptable to
          AstraZeneca, or (b) AstraZeneca in good faith believes that the
          outcome of such Infringement Suit is not likely to be favourable;
          provided, however, that AstraZeneca shall have the right to terminate
          this Agreement with respect to all of Europe if such country is in
          Europe and AstraZeneca shall have the right to terminate this
          Agreement in its entirety if such country is or is in a Major Market.

21.5 Termination for Material Breach. In the event that either Party (the
     "BREACHING PARTY") shall be in material default in the performance of any
     of its material obligations under this Agreement, in addition to any other
     right and remedy the other Party (the "COMPLAINING PARTY") may have, the
     Complaining Party may terminate this Agreement in its entirety by

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     *** prior written notice (the "NOTICE PERIOD") to the Breaching Party,
     specifying the breach and its claim of right to terminate, provided always
     that the termination shall not become effective at the end of the Notice
     Period if the Breaching Party cures the breach complained about during the
     Notice Period (or, if such default cannot be cured within such *** period,
     if the Breaching Party commences actions to cure such default within the
     Notice Period and thereafter diligently continues such actions); provided,
     however, that in the event that AstraZeneca is the Party in material
     default and the default is with respect to AstraZeneca's failure to comply
     with its obligation to use Commercially Reasonable Efforts as required
     under Section 8.1 with respect to the Licensed Products in a particular
     ***, Avanir shall have the right to terminate this Agreement only after it
     complies with Section 8.2 and only with respect to such *** and not in its
     entirety. It is understood that termination pursuant to this Section 21.5
     shall be a remedy of last resort and may be invoked only in the case where
     the breach cannot be reasonably remedied by the payment of money damages.
     If either Party initiates a dispute resolution procedure as permitted under
     this Agreement within *** following the end of the Notice Period to resolve
     the dispute for which termination is being sought and is diligently
     pursuing such procedure, including any litigation following therefrom, the
     termination shall become effective only if and when allowed through such
     dispute resolution procedure finally resolved. This Section 21.5 defines
     exclusively the Parties' right to terminate in case of any material breach
     of contract.

21.6 Change of Control. Upon a Change of Control of Avanir at any time during
     the Collaboration Term, by which Avanir becomes controlled by a company
     with a market capitalization in excess of *** U.S. Dollars ($***) and that
     has material parts of its operations in the health care industry,
     AstraZeneca shall have the right with immediate effect, by delivering
     written notice of termination to Avanir at any time within *** after the
     date of such Change of Control, to (a) terminate this Agreement in its
     entirety; or (b)

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     terminate only the Research Collaboration thereby ending the Collaboration
     Term; or (c) terminate Sections 3.6, 6.3.2 and 8.4 and have the IF, if
     established, dissolved. In the event AstraZeneca exercises the option under
     (b), AstraZeneca shall be under no obligation to provide Avanir with any
     further compensation pursuant to Article 9. Following such termination of
     the Collaboration Term, (x) Sections 3.6, 6.3.2 and 8.4 shall immediately
     cease to be in effect and the IF, if established, shall be dissolved, and
     (y) Avanir shall promptly provide AstraZeneca with all Collaboration
     Results generated by it under the Research Collaboration and not previously
     provided to AstraZeneca and shall promptly return to AstraZeneca all
     AstraZeneca Information and all other Confidential Information of
     AstraZeneca, including any and all copies thereof, and those portions of
     any documents, memoranda, notes, studies, analyses or other material
     prepared by or on behalf of Avanir that incorporate or are derived from
     such Confidential Information. For the avoidance of doubt, in the event of
     such termination, Avanir shall have no further rights to use any
     Collaboration Results, AstraZeneca Information or other Confidential
     Information of AstraZeneca for any purpose. The Agreement shall remain
     valid and in full force and effect in all other respects. Upon any other
     Change of Control of Avanir during the Research Collaboration, AstraZeneca
     shall be entitled with immediate effect by delivering written notice of
     termination to Avanir to terminate the Research Collaboration upon its
     reasonable determination during the *** period following the Change of
     Control in case Avanir (i) has failed to provide the *** required by this
     Agreement, (ii) has reassigned ***, (iii) has reprioritised its research
     programs away from the Research Collaboration, or (iv) has otherwise
     materially failed to deliver services as required under the Research Plan.
     In such event, the consequences of termination of the Research
     Collaboration shall be as set forth above following termination of the
     Research Collaboration.

21.7 Consequences of Termination.

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     21.7.1 Return of Material; Termination of Rights.

          (a)  In the event of termination of this Agreement in its entirety by
               AstraZeneca pursuant to Section 21.3, 21.4 or 21.6, or by Avanir
               pursuant to Section 21.5: (i) all rights and licences granted to
               AstraZeneca under this Agreement shall terminate, and (ii) each
               Party shall return all data, files, records and other materials
               in its possession or control containing or comprising the other
               Party's Information, or other Confidential Information to which
               such first Party does not retain rights hereunder (except one
               copy of which may be retained by the returning Party solely for
               archival purposes).

          (b)  In the event of termination of this Agreement with respect to one
               or more countries by AstraZeneca pursuant to Section 21.3, 21.4
               or 21.6, or by Avanir pursuant to Section 21.5: (i) all rights
               and licences granted to AstraZeneca under this Agreement shall
               terminate with respect to such country or countries, and (ii)
               each Party shall return all data, files, records and other
               materials in its possession or control containing or comprising
               the other Party's Information or other Confidential Information
               with respect to such country or countries to which such first
               Party does not retain rights hereunder (except one copy of which
               may be retained by the returning Party solely for archival
               purposes). For the avoidance of doubt, AstraZeneca shall have the
               right to retain all such Information, including Confidential
               Information, that is necessary or useful for AstraZeneca to
               Exploit Licensed Products and Improvements in the Territory.

          (c)  In the event of termination of this Agreement in its entirety or
               for one or more countries by AstraZeneca pursuant to Section 21.5
               or 21.9, Avanir shall deliver or otherwise return all data,
               files, records and other materials in its possession or control
               relating to the Licensed Compounds and Licensed Product or
               containing or comprising AstraZeneca's Information or other
               Confidential Information with respect to such country or
               countries

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               regarding which the Agreement has been terminated (except one
               copy of which may be retained by Avanir solely for archival
               purposes) and, without prejudice to any licence or right granted
               hereunder for any country regarding which this Agreement remains
               in force, all licences and other rights granted by Avanir to
               AstraZeneca under Article 3 shall continue in perpetuity and
               shall be fully paid up and AstraZeneca shall have no further
               obligations under Articles 9 and 10.

     21.7.2 Transfer of Materials. In the event of termination of this Agreement
          by AstraZeneca pursuant to Section 21.3, 21.4 or 21.6 or by Avanir
          pursuant to Section 21.5, (a) a copy of any and all documentation and
          data owned or controlled by AstraZeneca and in tangible form at the
          time of termination of the Agreement that has been generated with
          respect to Licensed Compounds, Licensed Products, their respective
          manufacture and that which is necessary to enable Avanir to continue
          development of a Licensed Product and the commercialisation thereof
          (collectively, the "ASTRAZENECA PRODUCT DATA"), shall be provided to
          Avanir, and Avanir may use such AstraZeneca Product Data at its
          discretion on a non-exclusive basis, but only to the extent necessary
          to enable Avanir to continue development of and to commercialise a
          Licensed Product, and (b) if such termination occurs after a Licensed
          Product has received Health Registration Approval (including price
          approval, if applicable), AstraZeneca shall, if permitted under local
          laws and regulations, promptly transfer to Avanir at Avanir's cost and
          expense any and all Health Registration Approvals obtained for the
          Licensed Products as well as any and all Regulatory Documentation and
          regulatory applications submitted to Health Authorities for the
          Licensed Product, provided that Avanir shall indemnify and hold
          harmless AstraZeneca and its Affiliates, Distributors and Sublicensees
          from any Losses with respect to the use of the AstraZeneca Product
          Data or the Exploitation of Licensed Compounds or Licensed Products
          under such Health Registration Approvals pursuant to Article 17 and
          any such AstraZeneca Product Data shall be subject to the
          confidentiality obligations set forth in Article 14. Avanir shall pay
          to

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          AstraZeneca, in consideration for the foregoing transfer of the
          AstraZeneca Product Data and, if applicable, the Health Registration
          Approvals and other Regulatory Documentation following termination by
          AstraZeneca in a situation where AstraZeneca considers termination of
          this Agreement reasonably necessary in order to ***, or, under the
          specific circumstance where upon termination at any time following
          completion of a ***, a royalty of *** percent (***%) of Net Sales
          (provided that, for purposes of this Section 21.7.2, references to
          AstraZeneca in such definition shall be deemed to be references to
          Avanir) of each Licensed Product Exploited by or on behalf of Avanir,
          its Affiliates or sublicensees from the First Commercial Sale of each
          such Licensed Product in a country until the *** anniversary of such
          First Commercial Sale in such country.

     21.7.3 Grant Back. In the event of termination of this Agreement in its
          entirety by AstraZeneca pursuant to Section 21.3, 21.4 or 21.6 or by
          Avanir pursuant to Section 21.5, Avanir shall have the right to elect,
          on written notice to AstraZeneca, for a period of *** from such
          termination, to obtain from AstraZeneca a non-exclusive,
          royalty-bearing licence under any Grant-Back Patents to the extent
          necessary for Avanir to continue the development and commercialisation
          of Licensed Compounds as developed by AstraZeneca up to the point of
          termination of this Agreement, provided that Avanir shall indemnify
          and hold harmless AstraZeneca and its Affiliates, Distributors and
          Sublicensees from any Losses with respect to the Exploitation of
          Licensed Compounds or Licensed Products under such licence pursuant to
          Article 17. Avanir shall pay AstraZeneca a royalty in respect of such
          licence, on terms to be agreed between AstraZeneca and Avanir. Avanir
          shall reimburse AstraZeneca for its reasonable costs and expenses
          incurred in the filing, prosecution and maintenance of the Grant-Back
          Patents. For the avoidance of doubt, the rights granted to Avanir

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          hereunder are restricted solely to Licensed Compounds and Licensed
          Products and AstraZeneca does not grant any rights whatsoever to any
          other compounds or products or to any IP Protection Rights other than
          to the Grant-Back Patents as set forth above. For purposes of this
          Section 21.7.3, "GRANT-BACK PATENTS" means any Patents owned or
          otherwise Controlled by AstraZeneca as of the effective date of such
          termination that claim the Licensed Compounds or Licensed Products, as
          applicable, solely as such Licensed Compounds or Licensed Products
          exist as of the termination of this Agreement by AstraZeneca pursuant
          to Section 21.3, 21.4 or 21.6 or by Avanir pursuant to Section 21.5,
          and that, as of such termination, AstraZeneca is free to licence to
          Avanir.

     21.7.4 Supply Obligations. In the event of termination of this Agreement in
          its entirety or with respect to one or more countries by AstraZeneca
          pursuant to Section 21.3, 21.4 or 21.6 or by Avanir pursuant to
          Section 21.5 and in order for Avanir to smoothly continue the
          commercialisation of the Licensed Compounds and Licensed Products in
          the Territory or such country(ies), as applicable, AstraZeneca shall,
          with the limitations set out below and for a maximum period of ***
          prior to Health Registration Approval or *** thereafter, supply Avanir
          in a timely manner with sufficient amount of Licensed Compound or
          Licensed Product in the Territory or such country(ies), as applicable,
          at AstraZeneca's fully absorbed costs ***. AstraZeneca's undertaking
          to supply is subject to AstraZeneca, upon termination of this
          Agreement, having in its possession appropriate and regulatory
          approved manufacturing methods and technologies for the Licensed
          Compound and Licensed Product up and running in the scales they are to
          be produced and available production capacity after meeting the
          requirements of AstraZeneca, its Affiliates, Distributors and
          Sublicensees, it being understood that AstraZeneca shall be under no
          obligation to develop or acquire

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          any manufacturing methods or other technologies in addition to what
          has been developed at the date of termination by it or on its behalf
          under this Agreement for the production of Licensed Compound and
          Licensed Product nor to expand its production capacity to meet the
          requirements of Avanir for Licensed Product. AstraZeneca does not
          represent or warrant that AstraZeneca will be able to produce clinical
          or commercial quantities of Licensed Product. The Parties will
          separately negotiate in good faith the logistical and other terms and
          conditions for such supplies, including appropriate provisions for the
          indemnification by Avanir of AstraZeneca for Avanir's or its
          Affiliates' Exploitation of the Licensed Compounds and Licensed
          Products supplied by AstraZeneca.

     21.7.5 Work-in-Progress. Upon termination of this Agreement with respect to
          one or more countries by Avanir pursuant to Section 21.5, AstraZeneca
          shall be entitled during the following ***, to finish any
          work-in-progress and to sell any inventory of the Licensed Product
          that remains on hand as of the date of the termination, so long as
          AstraZeneca pays Avanir the royalties applicable to said subsequent
          sales in accordance with the terms and conditions set forth in Section
          10.2.

     21.7.6 Unauthorised Sales. To the extent that Avanir has the right under
          this Section 21.7.6 to Exploit Licensed Products in one or more
          countries and to the extent permitted by law, Avanir shall have the
          right, both for itself and for its Affiliates, to Manufacture,
          distribute, market, promote, offer for sale and sell the Licensed
          Product only in such countries, provided that:

          (a)  Avanir shall not, and shall not permit its subsidiaries or
               authorize its other Affiliates or sublicensees to, engage in
               active sales of the Licensed Product in any country in Europe in
               which AstraZeneca's exclusive licence under this Agreement has
               not terminated or expired; and

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          (b)  Avanir shall not, and shall not permit its subsidiaries or
               authorize its other Affiliates to, distribute, market, promote,
               offer for sale or sell the Licensed Product directly or
               indirectly in any country outside of Europe in which
               AstraZeneca's exclusive licence under this Agreement has not
               terminated or expired.

          AstraZeneca shall not be obligated to provide Avanir with any other IP
          Protection Right or services than that which is explicitly provided
          for under this Section 21.7.

     21.7.7 Remedies. Early termination of this Agreement or the Research
          Collaboration by a Party shall in no way affect or limit such Party's
          right to claim against the other Party for any damages arising out of
          the breach of this Agreement.

21.8 Accrued Rights; Surviving Obligations. The termination of this Agreement
     shall not relieve the Parties from performing any obligations accrued prior
     to the date this Agreement terminates. Each Party's obligations under
     Sections 3.7.2, 5.6, 12.1, 12.2, 12.3, 21.7, 21.10 and this Section 21.8,
     and Articles 1,14, 15, 17, 18, 25, 26, 27, 30, 32, 33, 35 shall survive the
     termination or expiration of this Agreement.

21.9 Termination Upon Insolvency. Either Party may terminate this Agreement and
     AstraZeneca may terminate only the Research Collaboration, thereby ending
     the Collaboration Term, if, at any time, the other Party shall file in any
     court or agency pursuant to any statute or regulation of any state, country
     or jurisdiction, a petition in bankruptcy or insolvency or for
     reorganization or for an arrangement or for the appointment of a receiver
     or trustee of that Party or of its assets, or if the other Party proposes a
     written agreement of composition or extension of its debts, or if the other
     Party shall be served with an involuntary petition against it, filed in any
     insolvency proceeding, and such petition shall not be dismissed within
     sixty (60) days after the filing thereof, or if the other Party shall
     propose or be a party to any dissolution or liquidation, or if the other
     Party shall make an assignment for the benefit of its creditors. In case
     AstraZeneca elects to terminate the Research Collaboration only AstraZeneca
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     under no obligation to provide Avanir with any further compensation
     pursuant to Article 9 and what is stated in Section 21.6 (y) shall apply.

21.10 Rights in Bankruptcy. All rights and licences granted under or pursuant to
     this Agreement by Avanir are, and shall otherwise be deemed to be, for
     purposes of Section 365(n) of the U.S. Bankruptcy Code or analogous
     provisions of Applicable Law outside the United States, licences of right
     to "intellectual property" as defined under Section 101 of the U.S.
     Bankruptcy Code or analogous provisions of Applicable Law outside the
     United States (hereinafter "IP"). The Parties agree that AstraZeneca, as
     licensee of such rights under this Agreement, shall retain and may fully
     exercise all of its rights and elections under the U.S. Bankruptcy Code or
     any other provisions of Applicable Law outside the United States that
     provide similar protection for IP. The Parties further agree that, in the
     event of the commencement of a bankruptcy proceeding by or against Avanir
     under the U.S. Bankruptcy Code or analogous provisions of Applicable Law
     outside the United States, AstraZeneca shall be entitled to a complete
     duplicate of (or complete access to, as appropriate) any such IP and all
     embodiments of such IP, which, if not already in AstraZeneca's possession,
     shall be promptly delivered to it upon AstraZeneca's written request
     therefor.

22   FORCE MAJEURE

22.1 In this Agreement, "FORCE MAJEURE" means an event which is beyond a
     non-performing Party's reasonable control, including an act of God, act of
     the other Party, strike, lock-out or other industrial/labour disputes
     (whether involving the workforce of the Party so prevented or of any other
     Person), war, riot, civil commotion, terrorist act, malicious damage,
     epidemic, quarantine, fire, flood, storm, natural disaster or compliance
     with any law or governmental order, rule, regulation or direction
     (including changes in the requirements of the Health Authorities), whether
     or not it is later held to be invalid.

22.2 The Force Majeure Party shall, within thirty (30) days of the occurrence of
     a Force Majeure event, give notice in writing to the other Party specifying
     the nature and extent of the event of Force Majeure, its anticipated
     duration and any action being taken to avoid or minimize its effect.
     Subject to providing such notice and to Section 22.1, the

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     Force Majeure Party shall not be liable for delay in performance or for
     non-performance of its obligations under this Agreement, in whole or in
     part, nor shall the other Party have the right to terminate this Agreement,
     except as otherwise provided in this Agreement, where non-performance or
     delay in performance has resulted from an event of Force Majeure. The
     suspension of performance allowed hereunder shall be of no greater scope
     and no longer duration than is reasonably required.

22.3 The Force Majeure Party shall use reasonable endeavours, without being
     obligated to incur any expenditure or cost, to (a) bring the Force Majeure
     event to a close or (b) find a solution by which the Agreement may be
     performed despite the continuation of the event of Force Majeure.

23   ASSIGNMENT

     Neither Party may assign its rights or, except as provided in Sections 3.3,
     3.4 or 5.3, delegate its obligations under this Agreement, whether by
     operation of law or otherwise, in whole or in part without the prior
     written consent of the other Party, which consent shall not be unreasonably
     withheld or delayed, except that AstraZeneca shall always have the right,
     without such consent to perform any or all of its obligations and exercise
     any or all of its rights under this Agreement through any of its Affiliates
     or Sublicensees, and may assign any or all of its rights and delegate any
     or all of its obligations hereunder to any of its Affiliates. Either Party
     may assign any or all of its rights and delegate any or all of its
     obligations hereunder, subject to Section 21.6 in the case of an assignment
     by Avanir, to any successor in interest (whether by merger, acquisition,
     asset purchase or otherwise) to all or substantially all of the business to
     which this Agreement relates provided that the assigning Party shall
     provide written notice to the other within *** after such assignment or
     delegation; provided, however, in the event that any such transaction
     results in a Change of Control of AstraZeneca, Avanir shall be entitled to
     request further written assurances from the resulting entity re-affirming
     the commitment of the resulting

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                        CONFIDENTIAL TREATMENT REQUESTED

     entity to comply with the terms and conditions of this Agreement. Such
     further written assurances shall be delivered within *** of request by
     Avanir. Avanir may so request at any time during the *** period following
     completion of the subject transaction.

     Following the expiration of the Research Collaboration Avanir may assign
     its right to receive payments under this Agreement to a Third Party,
     provided always that any Indirect Taxes, other taxes or other costs that
     might apply in addition to what would have been the case had payments been
     made directly from AstraZeneca to Avanir as a consequence of such Avanir's
     assignment shall be carried by Avanir in their entirety. Any other proposed
     assignment by Avanir of its rights and obligations under this Agreement
     shall require the prior written consent of AstraZeneca. No assignment shall
     release either Party from responsibility for the performance of any accrued
     obligation of such Party hereunder. No assignment or delegation under this
     Agreement shall be effective until the assignee or delegate, as the case
     may be, accepts the assignment or delegation in writing. This Agreement
     shall be binding upon and enforceable against the successor to or any
     permitted assignee or permitted delegate from either of the Parties hereto.

     Any permitted successor of a Party or any permitted assignee of all of a
     Party's rights under this Agreement that has also assumed all of such
     Party's obligations hereunder in writing shall, upon any such succession or
     assignment and assumption, be deemed to be a party to this Agreement as
     though named herein in substitution for the assigning Party, whereupon the
     assigning Party shall cease to be a party to this Agreement and shall cease
     to have any rights or obligations under this Agreement. All validly
     assigned rights of a Party shall inure to the benefit of and be enforceable
     by, and all validly delegated obligations of such Party shall be binding on
     and be enforceable against, the permitted successors and assigns of such
     Party, provided that such Party, if it survives, shall remain jointly and
     severally liable for the performance of such delegated obligations under
     this

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                        CONFIDENTIAL TREATMENT REQUESTED

     Agreement. Any attempted assignment or delegation in violation of this
     Article 23 shall be void.

24   SEVERABILITY

     To the fullest extent permitted by Applicable Law, the Parties waive any
     provision of law that would render any provision in this Agreement invalid,
     illegal or unenforceable in any respect. If any provision of this Agreement
     is held to be invalid, illegal or unenforceable, in any respect, then such
     provision will be given no effect by the Parties and shall not form any
     part of this Agreement. To the fullest extent permitted by Applicable Law
     and if the rights or obligations of any Party will not be materially and
     adversely affected, all other provisions of this Agreement shall remain in
     full force and effect, and the Parties shall use their best efforts to
     negotiate a provision in replacement of the provision held invalid, illegal
     or unenforceable that is consistent with Applicable Law and achieves, as
     nearly as possible, the original intention of the Parties.

25   GOVERNING LAW; DISPUTE RESOLUTION

25.1 Governing Law. This Agreement shall be governed by and construed in
     accordance with the laws of New York, USA, excluding any conflicts or
     choice of law rule or principle that might otherwise refer construction or
     interpretation of this Agreement to the substantive law of another
     jurisdiction.

25.2 Arbitration. In the event of any controversy or claim arising out of or
     relating to any provision of this Agreement, the Parties shall try to
     settle their differences amicably between themselves. Any unresolved
     disputes arising between the Parties relating to, arising out of or in any
     way connected with this Agreement or any term or condition hereof, or the
     performance by either Party of its obligations hereunder, whether during
     the term or after termination of this Agreement, shall be resolved by final
     and binding arbitration. Whenever a Party shall decide to institute
     arbitration proceedings, it shall give

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     written notice to that effect to the other Party. Arbitration shall be held
     in ***, according to the rules of the International Chamber of Commerce
     ("ICC"). The arbitration will be conducted by a panel of three (3)
     arbitrators appointed in accordance with ICC rules; provided that each
     Party shall within thirty (30) calendar days after the institution of the
     arbitration proceedings appoint one arbitrator each, and such arbitrators
     shall select, if available, a third arbitrator within thirty (30) calendar
     days thereafter. If the two first arbitrators are unable to select a third
     arbitrator within such period, the third arbitrator shall be appointed in
     accordance with ICC rules. All arbitrators eligible to conduct the
     arbitration must agree to render their opinion(s) within thirty (30)
     calendar days of the final arbitration hearing. No arbitrator (nor the
     panel of arbitrators) shall have the power to award punitive damages under
     this Agreement and such award is expressly prohibited. Decisions of the
     arbitrators shall be confidential, final and binding on all of the Parties.
     Judgment on the award so rendered may be entered in a court having
     jurisdiction thereof. The losing Party to the arbitration (if any) as
     determined by the arbitrators shall pay the costs of arbitration. The
     proceedings, including any outcome, shall be confidential. Nothing in this
     Section 25.2 will preclude either Party from seeking equitable relief in
     accordance with Article 33 or interim or provisional relief from a court of
     competent jurisdiction, including a temporary restraining order,
     preliminary injunction or other interim equitable relief, concerning a
     dispute either prior to or during any arbitration if necessary to protect
     the interests of such Party or to preserve the status quo pending the
     arbitration proceeding.

26   INTERPRETATION OF CERTAIN EVIDENCE

     Any dispute with respect to whether a compound is a Collaboration Compound
     shall be subject to the provisions of Article 25, provided that, whatever
     the dispute resolution proceedings or procedures, the Parties agree that
     AstraZeneca's internal laboratory books and records from the relevant
     discovery process and its other relevant documentation

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                        CONFIDENTIAL TREATMENT REQUESTED

     (e.g., in-license agreements, invention disclosure documents or Patents
     disclosing or covering such compound) shall provide presumptive evidence
     with respect to any such dispute and Avanir shall bear the burden of
     proving that such documentation is not accurate.

27   NOTICES

27.1 Notice Requirements Any notice, request, demand, waiver, consent, approval
     or other communication permitted or required under this Agreement shall be
     in writing, shall refer specifically to this Agreement and shall be deemed
     given only if delivered by hand or sent by facsimile transmission (with
     transmission confirmed) or by internationally recognised overnight delivery
     service that maintains records of delivery, addressed to the Parties at
     their respective addresses specified in Section 27.2 or to such other
     address as the Party to whom notice is to be given may have provided to the
     other Party in accordance with this Article 27. Such notice shall be deemed
     to have been given as of the date delivered by hand or transmitted by
     facsimile (with transmission confirmed) or on the second business day (at
     the place of delivery) after deposit with an internationally recognised
     overnight delivery service. Any notice delivered by facsimile shall be
     confirmed by a hard copy delivered as soon as practicable thereafter. This
     Article 27 is not intended to govern the day-to-day business communications
     necessary between the Parties in performing their obligations under the
     terms of this Agreement.

27.2 Address for Notice

     For: AstraZeneca
          15 Stanhope Gate
          London, WIK 1LN, England
          Facsimile: 44 20 7304 5151
          For the attention of: Chris R. W. Petty, Assistant General Counsel

     For: Avanir
          11388 Sorrento Valley Road, Suite 200
          San Diego, California 92121
          Facsimile: (858) 658-7455
          For the attention of: Chief Financial Officer
          With a copy to:
          Heller Ehrman LLP

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                        CONFIDENTIAL TREATMENT REQUESTED

          4350 La Jolla Village Drive, 7th Floor
          San Diego, CA 92122
          Facsimile: (858) 450-8499
          For the attention of: Richard A. Kaufman

28   RELATIONSHIP OF THE PARTIES

     The status of a Party under this Agreement shall be that of an independent
     contractor. Nothing contained in this Agreement shall be construed as
     creating a partnership, joint venture or agency relationship between the
     Parties or, except as otherwise expressly provided in this Agreement, as
     granting either Party the authority to bind or contract any obligation in
     the name of or on the account of the other Party or to make any statements,
     representations, warranties or commitments on behalf of the other Party.
     All persons employed by a Party shall be employees of such Party and not of
     the other Party and all costs and obligations incurred by reason of any
     such employment shall be for the account and expense of such Party.

29   ENTIRE AGREEMENT

     This Agreement constitutes the entire agreement between the Parties with
     respect to the subject matter of the Agreement. This Agreement supersedes
     all prior agreements, whether written or oral, with respect to the subject
     matter of the Agreement. Each Party confirms that it is not relying on any
     representations, warranties or covenants of the other Party except as
     specifically set out in this Agreement. Nothing in this Agreement is
     intended to limit or exclude any liability for fraud. All Schedules
     referred to in this Agreement are intended to be and are hereby
     specifically incorporated into and made a part of this Agreement. In the
     event of any inconsistency between any such Schedules and this Agreement,
     the terms of this Agreement shall govern.

30   ENGLISH LANGUAGE

     This Agreement is written and executed in the English language. Any
     translation into any other language shall not be an official version of
     this Agreement and in the event of any conflict in interpretation between
     the English version and such translation, the English version shall
     prevail.

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31   AMENDMENT

     Any amendment or modification of this Agreement must be in writing and
     signed by authorised representatives of both Parties.

32   WAIVER AND NON-EXCLUSION OF REMEDIES

     A Party's failure to enforce, at any time or for any period of time, any
     provision of this Agreement, or to exercise any right or remedy shall not
     constitute a waiver of that provision, right or remedy or prevent such
     Party from enforcing any or all provisions of this Agreement and exercising
     any rights or remedies. To be effective any waiver must be in writing. All
     rights and remedies are cumulative and, except as expressly provided in
     Section 21.5 and elsewhere in this Agreement, do not exclude any other
     right or remedy provided by law or otherwise available.

33   EQUITABLE RELIEF

     Avanir acknowledges and agrees that the restrictions set forth in Section
     3.7.2 and Article 14 of this Agreement are reasonable and necessary to
     protect the legitimate interests of AstraZeneca and that AstraZeneca would
     not have entered into this Agreement in the absence of such restrictions,
     and that any breach or threatened breach of any provision of Section 3.7.2
     and Article 14 will result in irreparable injury to AstraZeneca for which
     there will be no adequate remedy at law. In the event of a breach or
     threatened breach of any provision of Section 3.7.2 and Article 14,
     AstraZeneca shall be authorised and entitled to obtain from any court of
     competent jurisdiction injunctive relief, whether preliminary or permanent,
     specific performance and an equitable accounting of all earnings, profits
     and other benefits arising from such breach, which rights shall be
     cumulative and in addition to any other rights or remedies to which
     AstraZeneca may be entitled in law or equity. Avanir agrees to waive any
     requirement that AstraZeneca (a) post a bond or other security as a
     condition for obtaining any such relief, and (b) show irreparable harm,
     balancing of harms, consideration of the public interest or inadequacy of
     monetary damages as a remedy. Nothing in this Article 33 is

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     intended, or should be construed, to limit AstraZeneca's rights to
     equitable relief or any other remedy for a breach of any other provision of
     this Agreement.

34   FURTHER ASSURANCE

     Each Party shall perform all further acts and things and execute and
     deliver such further documents as may be necessary or as the other Party
     may reasonably require to implement or give effect to this Agreement. For
     the avoidance of doubt, wherever in this Agreement an Affiliate of a Party,
     which is an Affiliate both at the Effective Date and at times thereafter,
     is either precluded from taking an action or is affirmatively required to
     take an action, the Party with which such Affiliate is affiliated may not
     obviate compliance with any such provision through the creation of an
     Affiliate after the Effective Date.

35   EXPENSES

     Except as otherwise expressly provided in this Agreement, each Party shall
     pay the fees and expenses of its respective lawyers and other experts and
     all other expenses and costs incurred by such Party incidental to the
     negotiation, preparation, execution and delivery of this Agreement.

IN WITNESS WHEREOF, the Parties hereto have executed this Agreement in two (2)
original copies of which, each of the Parties have taken one each.

SIGNED for and on behalf of             SIGNED for and on behalf of
AstraZeneca UK Limited                  Avanir Pharmaceuticals


/s/ Denise E Goode                      /s/ Charles Mathews
-------------------------------------   ----------------------------------------
Signature                               Signature

Name: Denise E Goode                    Name: Charles Mathews

Title: Director, Global Licensing       Title: Chairman of the Board of
       By power of attorney                    Directors

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                        CONFIDENTIAL TREATMENT REQUESTED

                                   SCHEDULE 1

                                  RESEARCH PLAN

                     REVERSE CHOLESTEROL TRANSPORT PROMOTER

                             ASTRAZENECA AND AVANIR

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                        CONFIDENTIAL TREATMENT REQUESTED

***

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***

<TABLE>
<S>   <C>
***   ***

***   ***

***   ***

***   ***

***   ***
</TABLE>

***

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                        CONFIDENTIAL TREATMENT REQUESTED

***

<TABLE>
<S>   <C>   <C>   <C>
      ***   ***   ***

***   ***   ***   ***

***   ***   ***   ***

***   ***         ***

***   ***   ***   ***

***   ***         ***

***   ***         ***
</TABLE>

***

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                                                                     Page 1 of 1

                                   SCHEDULE 2

                                Licensed Know-How

The Licensed Know-How is the information relating to the use of *** to affect
reverse cholesterol transport in animals which ***, possess, whether or not
reduced to writing, and which will be disclosed to the licensee.

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                                                                     Page 1 of 3

                                   SCHEDULE 3

                                 IND FILING PLAN

                                       ***

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                                   SCHEDULE 4

                        Licensed Patents and Applications

<TABLE>
<CAPTION>
                                                                                                DATE
CASE NO.   TITLE OF INVENTION   COUNTRY   STATUS   APPLICATION NO.   FILING DATE   PATENT NO   ISSUED   PUBLICATION NO.
--------   ------------------   -------   ------   ---------------   -----------   ---------   ------   ---------------
<S>        <C>                  <C>       <C>      <C>               <C>           <C>         <C>      <C>
           ***                    ****     ****          ***             ***

***

           ***                    ***       ***          ***             ***

***

           ***                    ***       ***          ***             ***

***                                                                                                             ***
</TABLE>

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                                   SCHEDULE 5

                          CONFIRMATORY PATENT LICENCES

Date: _______________________

Parties: ____________________

(1)  'The Licensor': ____________ having its registered office at __________.

(2)  'The Licensee': ____________ having its registered office at __________.

Recitals:

By an Agreement ('the Main Agreement') dated _________________ and made between
the Licensor and the Licensee the Licensor granted for the consideration therein
contained to the Licensee a licence under [Patent No _________________] ('the
Patent').

Operative provision:

In pursuance of the Main Agreement and for the consideration referred to in the
Main Agreement the Licensor hereby confirms the grant to the Licensee of the
exclusive licence from the Effective Date to manufacture, market, sell and
otherwise dispose of Licensed Products (as defined in the Main Agreement) for
the life of the Patent and subject to the provisions of the Main Agreement.

IN WITNESS of which this Agreement has been executed as a deed and delivered the
day and year first above written.

EXECUTED as a Deed by _________________ acting by:
[name of director] and:
[name of director/secretary]

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                                                                     Page 2 of 2

EXECUTED as a Deed by _________________ acting by:
[name of director] and:
[name of director/secretary]

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                        CONFIDENTIAL TREATMENT REQUESTED

                                   SCHEDULE 6

                                KEY PERSONNEL AND

                         ASTRAZENECA PRINCIPAL SCIENTIST

Key Personnel at Avanir:

***

***

AstraZeneca Principal Scientist:

***

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                                   SCHEDULE 7

                                  PRESS RELEASE

For business / financial media only

         ASTRAZENECA AND AVANIR ANNOUNCE GLOBAL ALLIANCE TO DISCOVER AND
         DEVELOP NOVEL REVERSE CHOLESTEROL TRANSPORT ENHANCING COMPOUNDS

AstraZeneca today announced an exclusive global licensing and research
collaboration agreement with Avanir to discover, develop and commercialise
Reverse Cholesterol Transport (RCT) enhancing compounds for the treatment of
cardiovascular disease.

RCT enhancing compounds are aimed to enhance the flow of lipids from tissues,
such as blood vessel walls, and the transportation of lipids to the liver for
excretion by promoting a natural process known as reverse cholesterol transport.
Compounds that enhance this pathway may potentially reverse existing vascular
disease in comparison to current agents that have to date only been shown to
prevent disease progression.

"AstraZeneca has a strategic commitment to find new treatments for
dyslipidaemia, and Reverse Cholesterol Transport is an exciting therapeutic area
for us. We wish to build on our existing strengths and this alliance will open
up new opportunities for AstraZeneca in the treatment of cardiovascular disease"
said Gunnar Olsson, Head of Cardiovascular Therapy Area, AstraZeneca.

Under the terms of the agreement, Avanir will receive an upfront payment of $10
million. In addition, Avanir is eligible for milestone payments totaling $330
million, contingent upon achievement of development and regulatory milestones
and on achievement of sales targets, together with the payment of stepped
royalties rising from single digit to low double digit rates dependent on sales
achieved. AstraZeneca will assume responsibility for development, and for both
product discovery and development costs, and both parties will contribute
scientific expertise in the research collaboration.

"Reverse Cholesterol Transport is an attractive target for the development of
drugs for cardiovascular disease. AstraZeneca has a long-standing record of
achievement in the development and commercialization in the dyslipidaemia area.
Their leadership in

<PAGE>

cardiovascular therapies makes them the ideal partner to maximize the potential
of this programme," said Martin Emanuele, VP Business Development, Avanir
Pharmaceuticals.

RCT is a natural process that involves flow of cholesterol from all tissues,
including the walls of blood vessels, and its subsequent transport to the liver
for metabolism and removal from the body. The process is complex, involving
several steps, and a variety of specialized transporter molecules and carrier
proteins to take cholesterol out of body tissues into the liver. Once
cholesterol is taken up by the liver, it can then be transported to the gall
bladder for excretion.

Enhancement of the reverse cholesterol pathway is promising because it is likely
to provide a more effective process for protecting blood vessels from vascular
disease induced by abnormal blood lipids. Currently available agents are
effective in prevention of the fuller development of additional lipid rich
plaque, but have yet to be proved effective in regressing or decreasing the
existing plaque burden. Enhancing the RCT pathway may be more effective at
reducing pre-existing vascular disease.

                                     -ends-

X June 2005

FOR FURTHER INFORMATION CONTACT:

MEDIA ENQUIRIES:

Edel McCaffrey, Tel: +44 (0) 207 304 5034

Steve Brown, Tel: +44 (0) 207 304 5033

INVESTOR ENQUIRIES:

Mina Blair, Tel: +44 (0) 207 304 5084

Jonathan Hunt, Tel: +44 (0) 207 304 5087

<PAGE>

NOTES TO EDITORS:

AstraZeneca is a major international healthcare business engaged in the
research, development, manufacture and marketing of prescription pharmaceuticals
and the supply of healthcare services. It is one of the world's leading
pharmaceutical companies with healthcare sales of over $21.4 billion and leading
positions in sales of gastrointestinal, cardiovascular, respiratory, oncology
and neuroscience products. AstraZeneca is listed in the Dow Jones Sustainability
Index (Global) as well as the FTSE4Good Index.

Avanir Pharmaceuticals is a drug discovery and development company focused on
developing and commercializing novel therapeutic products for the treatment of
chronic diseases. Avanir's product candidates address therapeutic markets that
include central nervous system and cardiovascular disorders, inflammation and
infectious disease. Further information about Avanir can be found at
www.avanir.com