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                                                                REDACTED VERSION

                                  EXHIBIT 10.18

                                       TO

                         LIGHT SCIENCES ONCOLOGY, INC.'S

                       REGISTRATION STATEMENT ON FORM S-1

                                 INITIALLY FILED

                                 APRIL 21, 2006

                           REGISTRATION NO. 333-133474

"[ * ]" = omitted, confidential material, which material has been separately
          filed with the Securities and Exchange Commission pursuant to a
          request for confidential treatment.

<PAGE>

                          LICENSE AND SUPPLY AGREEMENT

                           DATED AS OF APRIL 28, 2000

                                  BY AND AMONG

                         NIPPON PETROCHEMICALS CO., LTD

                                       AND

                            MEIJI SEIKA KAISHA, LTD.

                                       AND

                           LIGHT SCIENCES CORPORATION

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                                TABLE OF CONTENTS

<TABLE>
<CAPTION>
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<S>         <C>                                                             <C>
ARTICLE 1.  DEFINITIONS..................................................     1
   1.1      Affiliate....................................................     1
   1.2      Bulk.........................................................     2
   1.3      CMC Section..................................................     2
   1.4      Compound.....................................................     2
   1.5      Confidential Information.....................................     2
   1.6      Device.......................................................     2
   1.7      Disease Area.................................................     2
   1.8      DMF or Drug Master File......................................     2
   1.9      Effective Date...............................................     2
   1.10     Europe.......................................................     3
   1.11     FDA..........................................................     3
   1.12     Field........................................................     3
   1.13     First Commercial Sale........................................     3
   1.14     IND..........................................................     3
   1.15     Indication...................................................     3
   1.16     Kit..........................................................     3
   1.17     Licensed Know-How............................................     3
   1.18     Licensed Patents.............................................     4
   1.19     Licensed Technology..........................................     4
   1.20     Licensee Information.........................................     4
   1.21     Licensor.....................................................     4
   1.22     Manufacturing Know-How.......................................     5
   1.23     Market Exclusivity...........................................     5
   1.24     NDA..........................................................     5
   1.25     Net Sales....................................................     5
   1.26     Other Commercial Application.................................     5
   1.27     PDT or Photodynamic Therapy..................................     6
   1.28     Phase I Clinical Studies.....................................     6
   1.29     Phase II Clinical Studies....................................     6
   1.30     Phase III Clinical Studies...................................     6
   1.31     Pivotal Clinical Studies.....................................     6
   1.32     [ * ]........................................................     6
   1.33     Product......................................................     6
   1.34     Regulatory Approval..........................................     6
   1.35     Territory....................................................     6
   1.36     Valid Claim..................................................     6

ARTICLE 2.  GRANT OF LICENSE.............................................     6
   2.1      License Grant................................................     6
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<TABLE>
<S>         <C>                                                             <C>
   2.2      Sublicense...................................................     6

ARTICLE 3.  SUPPLY OF LICENSED KNOW-HOW, LICENSED PATENTS AND EXCHANGE OF
            DATA.........................................................     7
   3.1      Supply by Licensor...........................................     7
   3.2      Translation Cost.............................................     7
   3.3      Supply by Licensee...........................................     7

ARTICLE 4.  TRANSFER OF MANUFACTURING KNOW-HOW...........................     8
   4.1      Third-Party Manufacturer(s)..................................     8
   4.2      Transfer of Manufacturing Know-How...........................     8

ARTICLE 5.  UPFRONT LICENSE FEE, MILESTONE PAYMENTS AND ROYALTIES........     9
   5.1      Upfront License Fee..........................................     9
   5.2      Milestone Payments...........................................     9
   5.3      Royalty Payments.............................................    11
            5.3.1  Royalty in Countries Without Market Exclusivity.......    11
            5.3.2  Royalty in Countries Covered by Market Exclusivity....    12
            5.3.3  Royalties on Net Sales of Product for Other than
                   Therapeutic Application to Human Disease Areas........    13
            5.3.4  Extension of Market Exclusivity.......................    13
            5.3.5  Reduction of Royalties................................    14
            5.3.6  Quarterly Payments in U.S. Dollars....................    14
            5.3.7  Royalty Statement.....................................    14
            5.3.8  [ * ] Product and Kit.................................    15
            5.3.9  Sales to Affiliates and Sublicensees..................    15
            5.3.10 Records...............................................    15
   5.4      Bank Remittance..............................................    16
   5.5      Late Payments................................................    16
   5.6      Taxes and Withholdings.......................................    16

ARTICLE 6.  DEVELOPMENT..................................................    16
   6.1      Due Diligence................................................    16
   6.2      Compliance with Regulations..................................    17
   6.3      Progress Report..............................................    17
   6.4      Failure of Due Diligence.....................................    17
   6.5      Licensee Information.........................................    19
   6.6      Transfer of IND..............................................    19

ARTICLE 7.  REPORTS OF ADVERSE EVENTS....................................    19
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<TABLE>
<S>         <C>                                                             <C>
ARTICLE 8.  SUPPLY OF THE BULK AND PRODUCT BY MEIJI......................    20
   8.1      Bulk Supply..................................................    20
   8.2      Product Supply...............................................    21
   8.3      Room Temperature Stability Studies...........................    21
   8.4      Compliance With Specifications...............................    21
            8.4.1  Audit.................................................    21
            8.4.2  Meiji Responsibility for Compliance With
                   Specifications, Including cGMP........................    21
   8.5      Forecasting, Orders, Delivery and Acceptance.................    22
            8.5.1  Forecasting and Ordering of Supply for Development....    22
            8.5.2  Shipment of Bulk and Product for Development..........    22
            8.5.3  Payment...............................................    22
            8.5.4  Acceptance............................................    22
   8.6      Term of Supply Obligation....................................    23

ARTICLE 9.  SALES AND PROMOTION..........................................    23
   9.1      Commercial Sale..............................................    23
   9.2      Sales Promotion..............................................    23
   9.3      Supply of Promotional Materials..............................    24
   9.4      Packaging Reference..........................................    24

ARTICLE 10. ANTI-INFECTIVES: MEIJI RIGHT OF FIRST NEGOTIATION............    24

ARTICLE 11. LICENSEE'S DEVICE............................................    24

ARTICLE 12. PRODUCT LIABILITY AND INDEMNIFICATION........................    25
   12.1     Licensor's Indemnification of Licensee.......................    25
   12.2     Licensee's Indemnification of Licensor.......................    25
   12.3     Indemnification Obligations with respect to Bulk and Product
            Supplied by Meiji............................................    26

ARTICLE 13. TRADEMARKS...................................................    26

ARTICLE 14. PATENTS......................................................    26
   14.1     Patent Maintenance...........................................    26
   14.2     Extension of Licensed Patent Term............................    26
   14.3     Third-Party Infringement of Licensed Patents.................    26
   14.4     Alleged Infringement of Third-Party Patents..................    27

ARTICLE 15. INVENTIONS...................................................    29
   15.1     Licensee's Inventions........................................    29
   15.2     Licensor's Inventions........................................    30
   15.3     Joint Inventions.............................................    30

ARTICLE 16. TERM AND TERMINATION.........................................    31
</TABLE>

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<TABLE>
<S>         <C>                                                             <C>
   16.1     Term.........................................................    31
   16.2     Termination by Mutual Agreement..............................    31
   16.3     Breach.......................................................    31
   16.4     Insolvency or Bankruptcy.....................................    32
   16.5     Serious Events...............................................    32
   16.6     Effect of Termination........................................    32
   16.7     Survival of Liability and Other Obligations..................    34

ARTICLE 17. FORCE MAJEURE................................................    34

ARTICLE 18. CONFIDENTIALITY AND DISCLOSURE...............................    34
   18.1     Confidentiality..............................................    34
   18.2     Disclosure...................................................    35
   18.3     Prior Confidentiality Agreement..............................    35

ARTICLE 19. REPRESENTATIONS AND WARRANTIES...............................    35
   19.1     By Licensor..................................................    35
   19.2     By Licensee..................................................    37

ARTICLE 20. MISCELLANEOUS................................................    38
   20.1     Assignment...................................................    38
   20.2     Severability.................................................    38
   20.3     Notices......................................................    38
   20.4     Applicable Law...............................................    39
   20.5     Entire Agreement.............................................    39
   20.6     Headings.....................................................    39
   20.7     Independent Contractors......................................    39
   20.8     Waiver.......................................................    40
   20.9     Dispute Resolution...........................................    40
   20.10    Arbitration..................................................    40
   20.11    Public Announcements.........................................    40
   20.12    Limitations of Liability.....................................    41
   20.13    Counterparts.................................................    41
   20.14    Official Language............................................    41
   20.15    Further Documents............................................    41
</TABLE>

EXHIBIT A - Licensed Patents

EXHIBIT B - Development Plan

EXHIBIT C - Transfer of IND

EXHIBIT D - List of Documents to be Translated
<PAGE>

                          LICENSE AND SUPPLY AGREEMENT

     THIS LICENSE AND SUPPLY AGREEMENT (the "Agreement") is made as of the 28th
day of April, 2000 (the "Effective Date"), by and among:

     Nippon Petrochemicals Co., Ltd., a Japanese corporation having its
principal place of business at 3-1, Uchisaiwai-cho 1-chome, Chiyoda-ku, Tokyo
100-8530, Japan (hereinafter referred to as "NPC");

     Meiji Seika Kaisha, Ltd., a Japanese corporation having its principal place
of business at 4-16, Kyobashi 2-chome, Chuo-ku, Tokyo 104-8002, Japan
(hereinafter referred to as "Meiji");

     (Meiji and NPC shall hereinafter be individually referred to as such and
collectively referred to as "Licensor", as further provided in Section 1.21
below); and

     Light Sciences Limited Partnership, a Washington State limited partnership
having its principal place of business at 1065-12th Avenue NW, Suite E-5,
Issaquah, Washington 98027, U.S.A. (hereinafter referred to as "Licensee").

                                   WITNESSETH

     WHEREAS, either NPC or Meiji is the owner of the Licensed Patents (as
hereinafter defined) covering a photosensitizing agent coded NPe6 (also known as
ME2906), which is potentially useful in photodynamic therapy, and is also the
owner of the Licensed Know-How (as hereinafter defined) relating thereto; and

     WHEREAS, Licensee wishes to obtain a worldwide (except in Japan) exclusive
license to develop, make, have made and commercialize the Product (as
hereinafter defined); and

     WHEREAS, Licensor is willing to grant Licensee such license under the terms
and conditions set forth in this Agreement;

     NOW, THEREFORE, in consideration of the obligations and promises as set
forth herein, the parties do hereby agree as follows:

ARTICLE 1. DEFINITIONS

     As used in this Agreement, the following terms shall have the following
respective meanings:

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     1.1 AFFILIATE means any corporation or other entity which controls, is
controlled by, or is under common control with a party to this Agreement. A
corporation or other entity shall be regarded as in control of another
corporation or entity if it owns or controls directly or indirectly fifty
percent (50%) or more of the voting power of the other corporation or entity or
otherwise has the power to control its general activities, but in each case only
so long as such ownership or control shall continue.

     1.2 BULK means the Compound in bulk form.

     1.3 CMC SECTION means the Section on [ * ].

     1.4 COMPOUND means a photosensitizing compound coded [ * ].

     1.5 CONFIDENTIAL INFORMATION means the Licensed Know-How, the Licensee
Information and any information, data, improvements, inventions, development,
commercialization or business plans or development or royalty reports relating
to the Compound, the Bulk, the Product, the Kit and/or the Device which a party
discloses to the other party, except any portion thereof which:

          (i)  was already known to the receiving party, other than under an
               obligation of confidentiality, at the time of disclosure, as
               documented by written records;

          (ii) is or was disclosed to the receiving party, other than under an
               obligation of confidentiality, by a third person with a right to
               make such disclosure;

          (iii) was or becomes part of the public domain through no fault or
               breach of the receiving party; or

          (iv) is or was independently developed by personnel of the receiving
               party and without access or reference to the information
               disclosed by the other party, as evidenced by the receiving
               party's written records.

     1.6 DEVICE means any light generation and/or light delivery device(s)
acquired, developed, produced and/or manufactured by or on behalf of Licensee
for use with the Product in the Field.

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     1.7 DISEASE AREA means [ * ].

     1.8 DMF or DRUG MASTER FILE means the information defined in 21 C.F.R.
314.420 or any successor to such provision, or any foreign counterpart thereof,
and filed with the FDA, or any foreign equivalent thereof, by or on behalf of
Meiji, [ * ] or Licensee with respect to the manufacture of the Bulk or the
Product, as applicable, in support of an IND or NDA for the Product.

     1.9 EFFECTIVE DATE means the date first written above.

     1.10 EUROPE means the European Union and any country that is a member of
the European Union.

     1.11 FDA means the United States (U.S.) Food and Drug Administration or any
successor entity thereto.

     1.12 FIELD means any treatment, diagnosis or monitoring of any Disease Area
in humans or animals and all Other Commercial Applications of the Product.

     1.13 FIRST COMMERCIAL SALE means, on a country-by-country basis and an
Indication-by-Indication basis, the first sale of the Product or the Kit in a
country in the Territory by Licensee, its Affiliates or sublicensees to any
unaffiliated third party.

     1.14 IND means an Investigational New Drug Application filed with the FDA
to commence human clinical testing of a drug, or any foreign counterpart
thereof.

     1.15 INDICATION means a specific type of disease within a Disease Area; for
the avoidance of doubt, [ * ].

     1.16 KIT means a combination of the Product and a consumable light delivery
apparatus when sold collectively for a single price on a unit-treatment basis.

     1.17 LICENSED KNOW-HOW means any and all proprietary data, information,
trade secrets, formulations, inventions (including new formulations),
improvements, know-how and technology (other than the Licensed Patents) owned or
controlled by Licensor, their Affiliates or licensees (excluding Licensee), as
of the Effective Date or thereafter during the term of this Agreement relating
to the Compound, the Bulk and/or the Product, including but not limited to, all
pharmacological and toxicological data, all non-clinical, clinical and
regulatory data, results and reports (including, without limitation, all data,
results and reports submitted by, or in the possession or

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control of, all third parties generating such data, results and reports on
behalf of Licensor, their Affiliates or licensees (excluding Licensee), [ * ]
and [ * ], to the extent Licensor has the right, or can reasonably obtain the
right at no cost, to disclose such information to Licensee), formulation data,
the CMC Section(s) submitted by Meiji, the Drug Master File filed by or on
behalf of Meiji, the Manufacturing Know-How, copies of all written
communications and submissions to and from regulatory authorities and pricing
authorities in the United States and Japan, and a detailed written summary of
all substantive oral communications and discussion with such authorities;
provided that Licensed Know-How excludes Manufacturing Know-How not existing on
the Effective Date but to be owned or controlled by Licensor after the Effective
Date and also excludes Licensor's proprietary data, information, trade secrets,
formulations, inventions, improvements, know-how and technology pertaining only
to Other Commercial Applications of the Product.

     1.18 LICENSED PATENTS means (i) all patents and patent applications in the
Territory set forth in Exhibit A attached hereto and incorporated by reference
herein, and any patents which may issue from the patent applications listed in
Exhibit A, in each case together with any substitutions, extensions, additions,
reissues, reexaminations, renewals, divisionals, continuations,
continuations-in-part and supplementary patent certificates thereof or therefor,
owned or controlled by Licensor as of the Effective Date or thereafter during
the term of this Agreement relating to the Compound and/or the Product and/or
Manufacturing Know-How (Manufacturing Know-How existing as of the Effective
Date), and (ii) to the extent of Meiji's or NPC's interest therein and subject
to Section 5.3.4, all other patents and applications in the Territory owned or
controlled by Licensor, or any of their Affiliates, during the term of this
Agreement relating to the Compound and/or Product or methods of use for the
Compound or Product, together with any substitutions, extensions, additions,
reissues, reexaminations, renewals, divisionals, continuations-in-part and
supplementary patent certificates thereof or therefor, excluding such other
patents to be owned or controlled by Licensor or any of their Affiliates after
the Effective Date pertaining to inventions for the manufacture of the Compound,
Bulk and Product invented after the Effective Date and such other patents
pertaining only to Other Commercial Applications of the Product.

     1.19 LICENSED TECHNOLOGY means the Licensed Know-How and the Licensed
Patents.

     1.20 LICENSEE INFORMATION means any and all proprietary data, information
and know-how arising out of all development activities hereunder with respect to
the

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Compound, the Bulk and the Product conducted by or on behalf of Licensee, its
Affiliates or sublicensees during the term of this Agreement, including, without
limitation, all pharmacological, toxicological, non-clinical, clinical and
regulatory data, results and reports (including, without limitation, all data,
results and reports submitted by, or in the possession or control of all third
parties generating such data, results and reports on behalf of Licensee, its
Affiliates or sublicensees, all to the extent Licensee has the right, or can
reasonably obtain the right at no cost, to disclose such information to
Licensor; provided that, Licensee's patentable inventions (including
proprietary, new processes and formulations and new uses of the Compound) and
patentable improvements pertaining to the Compound, the Bulk and the Product are
excluded from Licensee Information and, instead, are addressed in Section 15.1
below; provided further that Licensee Information excludes Licensee's
proprietary data, information and know-how pertaining to the manufacture of the
Compound, the Bulk and the Product, and also excludes Licensee's proprietary
data, information and know-how pertaining only to Other Commercial Applications
of the Product. For the sake of clarification, Licensee Information excludes
Licensee's proprietary data, information, and know-how related to its Device(s),
rights to which are as set forth in Article 11;

     1.21 LICENSOR means Meiji and NPC; the rights and obligations of Licensor
are and shall be the joint and several rights and obligations of Meiji and NPC;
except where this Agreement expressly provides otherwise, Meiji shall be
authorized to act for and on behalf of Licensor for all purposes in connection
with this Agreement; Licensee's notices and communications to Meiji shall be
deemed notices and communications to Licensor; Meiji's notices and
communications to Licensee shall be deemed notices and communications from
Licensor; and Licensee shall be entitled to rely on the actions of Meiji as
being the actions of Licensor.

     1.22 MANUFACTURING KNOW-HOW means all data, know-how, technical
information, processes, trade secrets, inventions and improvements relating to
the manufacture of the Bulk and/or the Product, including all Drug Master Files,
which is owned or controlled by, or filed on behalf of, Meiji.

     1.23 MARKET EXCLUSIVITY means, on a country-by-country basis and an
Indication-by-Indication basis, the status in which, and the period during
which, either (x) the manufacture, use or sale of the Product would infringe a
Valid Claim of the Licensed Patents enforceable in such country in the absence
of the license granted herein, or (y) the Product is otherwise legally protected
with market exclusivity conferred by the governing authorities of such country
(including, but not limited to, the U.S. Waxman-Hatch Act or Drug Price
Competition and Patent Term Restoration Act or EC Directive 65/65/EEC or
87/21/EEC), provided such legal protection is granted for and based on the
Licensed Technology and/or data generated therefrom,

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as opposed to other intellectual property rights or data covering the Product
independent of the Licensed Technology.

     1.24 NDA means a New Drug Application and all supplements filed pursuant to
the requirements of FDA, and any foreign counterparts thereof, to commence
commercial sale of a drug, including all documents, data and other information
concerning the Compound, the Product and/or the Kit which are necessary for
approval of such application.

     1.25 NET SALES means the gross amounts invoiced by Licensee, its Affiliates
or sublicensees for sales of the Product and/or the Kit, as applicable, to
unrelated third parties (distributors, agents, wholesalers, customers or
reimbursement organizations, as the case may be) less [ * ] of such gross
amounts. For the sake of clarification, amounts invoiced for transfers between
and among Licensee, its Affiliates and sublicensees shall not be included in the
calculation of Net Sales. Section 5.3.2(a)(ii) sets forth the calculation of Net
Sales of the Product component of a Kit.

     In the event any Product or Kit contains, in addition to the Compound, one
or more other active ingredients, the gross selling price for purposes of
determining Net Sales on such combination shall be calculated by [ * ]. In the
event that no separate sale of either such above-designated Product or Kit or
such above-designated other active ingredient(s) is made by Licensee, its
Affiliates or sublicensees during the royalty reporting period in which the sale
was made, the parties shall, for purposes of determining Net Sales, [ * ].

     1.26 OTHER COMMERCIAL APPLICATION means any application of the Product not
related to the treatment, diagnosis or monitoring of any Disease Area in humans
or animals.

     1.27 PDT or PHOTODYNAMIC THERAPY means the treatment, diagnosis and
monitoring of diseases or Other Commercial Applications by application of light
with a photosensitizing active agent.

     1.28 PHASE I CLINICAL STUDIES means the type of studies defined in 21
C.F.R. 312.21(a) or any successor to such provision and the foreign equivalent
thereof.

     1.29 PHASE II CLINICAL STUDIES means the type of studies defined in 21
C.F.R. 312.21(b) or any successor to such provision and the foreign equivalent
thereof.

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     1.30 PHASE III CLINICAL STUDIES means the type of studies defined in 21
C.F.R. 312.21(c) or any successor to such provision and the foreign equivalent
thereof.

     1.31 PIVOTAL CLINICAL STUDIES means that portion of the clinical
development program which is the last clinical trial step required to be
completed prior to the filing of an NDA.

     1.32 [ * ].

     1.33 PRODUCT means any formulation containing the Compound as an active
ingredient in the finished form packaged and labeled and suitable for use by the
ultimate customer. A Kit is not a Product but contains a Product.

     1.34 REGULATORY APPROVAL means all governmental approvals, registrations,
licenses and authorizations necessary for the commercial sale of the Product in
a country in the Territory, including but not limited to marketing
authorization, pricing approval and pricing reimbursement, as applicable.

     1.35 TERRITORY means all countries in the world except for Japan.

     1.36 VALID CLAIM means any claim of an issued and unexpired patent in the
Licensed Patents which has not been held unenforceable, unpatentable or invalid
by a decision of a court or government agency of competent jurisdiction,
unappealable or unappealed within the time allowed for appeal, or which has not
been admitted by the holder of the patent to be invalid or unenforceable through
reissue, disclaimer or otherwise.

ARTICLE 2. GRANT OF LICENSE

     2.1 License Grant. Licensor hereby grants to Licensee an exclusive (even as
to Licensor) license, with the right to grant sublicenses, to research and
develop, use, make, have made, distribute, offer for sale, sell, import and
export the Bulk, Compound, Product and Kit in the Field in the Territory under
the Licensed Technology. Notwithstanding the foregoing, Licensor reserves the
non-exclusive right, with the right to grant licenses, only to conduct research
in the Territory regarding Other Commercial Applications of the Product.

     2.2 Sublicense. In the event that Licensee grants a sublicense hereunder to
any entity, Licensee shall inform Licensor, subject to the confidentiality
provisions of

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this Agreement, of the name(s) of such sublicensee(s) in advance (except that
Licensee need not inform Licensor in advance if Licensee's license rights become
semi-exclusive as provided in Article 6). Such sublicensees shall be subject to
applicable provisions of this Agreement, and Licensee shall incorporate into the
agreements with such sublicensees all the obligations of Licensee contained in
this Agreement to the extent that such obligations are relevant to and
applicable to such sublicensees. In the event that Licensee sublicenses to any
entity for the sale of Product in the Territory or any part of the Territory,
Licensee shall continue to be responsible for paying any royalties due and
payable on Net Sales in the Territory.

ARTICLE 3. SUPPLY OF LICENSED KNOW-HOW, LICENSED PATENTS AND EXCHANGE OF DATA

     3.1 Supply by Licensor. Promptly after Licensor's receipt of the Upfront
License Fee provided in Section 5.1, Licensor shall furnish Licensee without
charge with all the Licensed Know-How then available to Licensor that is
reasonably necessary or useful to Licensee, its Affiliates and sublicensees for
the development of the Product and/or Kit, the conduct of pre-clinical and
clinical studies, the preparation and submission of filings for Regulatory
Approval of the Product and/or the Kit and the maintenance of Regulatory
Approvals, and the manufacture of Bulk and/or Product (as specified in Article
4.2). Further, during the term of this Agreement, Licensor shall promptly
furnish Licensee with any and all Licensed Know-How which hereafter becomes
available to Licensor that is reasonably necessary or useful to Licensee, its
Affiliates and sublicensees for the development of the Product and/or Kit, the
conduct of pre-clinical and clinical studies, the preparation and submission of
filings for Regulatory Approval of the Product and/or Kit and the maintenance of
Regulatory Approvals. In addition, promptly after Licensor's receipt of the
Upfront License Fee provided in Section 5.1, and on an ongoing basis thereafter
during the term of this Agreement as additional documentation becomes available,
Licensor shall provide to Licensee, without charge to Licensee, all copies of
all the Licensed Patents (including copies of all communications and
correspondence by or on behalf of Licensor and the relevant patent offices
related to patent applications included in the Licensed Patents). Consistent
with Licensee's obligation under Section 6.3, Meiji shall report semi-annually
to Licensee on the progress status of its development and commercialization of
the Product in Japan.

     3.2 Translation Cost. Licensor shall, as soon as reasonably possible,
[ * ], translate into English the Licensed Know-How written in Japanese which is
described on Exhibit D. Licensor shall provide such Licensed Know-How to

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Licensee in such translated form (and shall also provide the Japanese form to
Licensee at Licensee's request). With respect to Licensed Know-How existing as
of the Effective Date that is not translated into English and Licensed Know-How
that first comes into existence during the term of this Agreement after the
Effective Date, if Licensee requests translation into English of such Licensed
Know-How that is written in Japanese, Licensor shall, at Licensee's request,
make arrangements for having outside translators prepare English translations,
and Licensee shall bear the cost of such translation work.

     3.3 Supply by Licensee. From time to time during the term of this
Agreement, so long as Meiji, its Affiliates or licensees are developing and
commercializing the Product in Japan, Licensee shall furnish Meiji without
charge, for use solely in Japan in connection with the Product by Meiji, its
Affiliates and licensees in Japan, with the Licensee Information which hereafter
becomes available to Licensee that is necessary or useful to Meiji, its
Affiliates and its licensees for the development of Product, the conduct of
pre-clinical and clinical studies, the preparation and submission of filings for
Regulatory Approval of the Product in Japan and the maintenance of such
Regulatory Approvals.

ARTICLE 4. TRANSFER OF MANUFACTURING KNOW-HOW

     4.1 Third-Party Manufacturer(s). As soon as practically possible after the
Effective Date, Licensee shall identify a third-party manufacturer or
manufacturers of choice who will undertake to manufacture the Bulk and the
Product for Licensee (hereinafter referred to as "Third-Party Manufacturer(s)").
In the process of evaluating candidates to be the Third-Party Manufacturer(s)
and retaining consultants to assist Licensee in such process, and in the
agreement(s) with the selected Third-Party Manufacturer(s), Licensee shall
obtain appropriate non-disclosure agreements from such candidates, consultants
and Third-Party Manufacturer(s) to whom Licensee discloses the Manufacturing
Know-How in order to protect the Manufacturing Know-How.

     4.2 Transfer of Manufacturing Know-How. During a period ending [ * ] months
following the Effective Date, such period to be extended up to an additional
[ * ] months by mutual agreement of Meiji and Licensee if reasonably necessary
(such agreement not to be unreasonably withheld), Meiji shall, upon request by
Licensee, and [ * ] except for the reimbursement of expenses as provided in
subsection (c) below, transfer and furnish the Manufacturing Know-How existing
as of the Effective Date to Licensee and the Third-Party Manufacturer(s)
selected by

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Licensee, in a manner to be mutually agreed upon, and shall provide all
necessary and useful technical assistance and training to facilitate the
Third-Party Manufacturer(s)' use of such Manufacturing Know-How and their
effective and efficient manufacture of Bulk and/or Product. The transfer of such
Manufacturing Know-How will occur by means of (i) qualified technical personnel
of the Third-Party Manufacturer(s) (and, in Licensee's discretion, its
representatives and consultants) visiting Meiji's facilities and/or, (ii) at
Licensee's request, by Meiji dispatching qualified technical personnel to the
facilities of the Third-Party Manufacturer(s), subject to the following
conditions in subsections (a) - (c) below. In addition to such visits, qualified
Meiji personnel shall, via telephone or e-mail, provide consultation with
respect to such Manufacturing Know-How from time to time in response to
reasonable requests from the Third-Party Manufacturer(s) or Licensee:

          (a) With respect to the dispatch of technical personnel by both Meiji
and the Third-Party Manufacturer(s) to the facilities of the other, the timing
of dispatch, the number of personnel to be dispatched (subject to (c) (i) below
in the case of Meiji's dispatch of its personnel) and the duration of their stay
shall be mutually and reasonably agreed upon by the parties in advance.

          (b) With respect to the dispatch of technical personnel of the
Third-Party Manufacturer(s) to Meiji (and in Licensee's discretion, its
personnel and consultants), all expenses incurred in connection with the
dispatch of such personnel shall be borne by Licensee or the Third-Party
Manufacturer(s).

          (c) With respect to the dispatch of Meiji's technical personnel to the
Third-Party Manufacturer(s) (if requested by Licensee):

          (i)  The number of Meiji personnel to be dispatched in one trip shall
               not exceed [ * ], both of whom shall be qualified to transfer the
               Manufacturing Know-How and provide technical assistance and
               training to the Third-Party Manufacturer(s); and

          (ii) The total number of days of each Meiji employee's stay at the
               facilities of the Third-Party Manufacturer(s), including his/her
               traveling days (but excluding holidays and weekends), shall not
               exceed [ * ] days per person; and

          (iii) Licensee or the Third-Party Manufacturer(s) shall reimburse
               Meiji for round-trip business class air fares, in-land traveling

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               expenses, first class hotel expenses and reasonable living
               expenses actually incurred by the Meiji personnel during their
               visit(s) to the facilities of the Third-Party Manufacturer(s). In
               addition, if Meiji personnel stay more than [ * ] days per person
               at the facilities of the Third-Party Manufacturer(s) (e.g., [ * ]
               Meiji personnel each staying a total of more than [ * ] days in
               one or more trips; not, e.g., [ * ] Meiji personnel staying [ * ]
               days each), then Licensee shall also reimburse and pay Meiji for
               the actual salaries (excluding overhead) of such Meiji personnel
               for the days in excess of [ * ] days that each such person is at
               the facilities of the Third-Party Manufacturer(s), including
               traveling days, holidays and weekends.

Should Licensee reasonably require further assistance with respect to the
transfer of Manufacturing Know-How existing as of the Effective Date, Meiji
shall provide such assistance subject to the terms to be reasonably agreed upon
by the parties.

ARTICLE 5. UPFRONT LICENSE FEE, MILESTONE PAYMENTS AND ROYALTIES

     5.1 Upfront License Fee. In consideration of the license granted under
Article 2 and Licensor's fulfillment of its other obligations and undertakings
under this Agreement, Licensee shall pay to Licensor a non-refundable upfront
license fee in the amount of [ * ] within [ * ] days after the Effective Date.

     5.2 Milestone Payments. In consideration of the license granted under
Article 2 and Licensor's fulfillment of its other obligations and undertakings
under this Agreement, Licensee shall make the following (and only the following)
non-refundable milestone payments to Licensor within [ * ] days after the event
specified below. Such milestones refer only to the therapeutic application of
the Product or Kit to human Disease Areas.

          (a) With respect to Oncology (Up to US$15 million in total):

          (i)  [ * ];

          (ii) [ * ];

          (iii) [ * ];

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          (iv) [ * ]

          (v)  [ * ].

For the sake of clarification with respect to the above milestone payments,
should Licensee file an NDA for approval of Product for the first Indication in
the Oncology Disease Area [ * ].

          (b) With respect to Ophthalmology (Up to [ * ] in total):

          (i)  [ * ];

          (ii) [ * ]

          (iii) [ * ].

          (c) With respect to Third Disease Area (excluding Oncology and
Ophthalmology) (Up to [ * ] in total):

          (i)  [ * ]

          (ii) [ * ].

          (d) With respect to Fourth Disease Area (excluding Oncology,
Ophthalmology and the Third Disease Area) (Up to [ * ] in total):

          (i)  [ * ]

          (ii) [ * ].

     5.3 Royalty Payments. In consideration of the license granted under Article
2 and Licensor's fulfillment of its other obligations and undertakings under
this Agreement, Licensee shall pay to Licensor a non-refundable royalty, on a
country-by-country basis and (subject to Section 5.3.8) an
Indication-by-Indication basis, on the Net Sales of the Product and the Kit sold
by Licensee, its Affiliates and sublicensees in the Territory.

     5.3.1 Royalty in Countries Without Market Exclusivity. With respect to all
countries in which no Market Exclusivity exists for a given Indication (i.e., in
contrast to countries in which Market Exclusivity exists for a period of time,
but then expires), Licensee (subject to Sections 5.3.5, 5.3.8 and 5.3.9 below)
shall pay the following

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royalty on Net Sales of the Product or the Kit (as the case may be) sold in such
country for such Indication for therapeutic application to human Disease Areas
from the date of the First Commercial Sale in such country until the earlier of
(x) the date of expiration of the Market Exclusivity for such Indication in the
U.S. or (y) the tenth anniversary of the date of the First Commercial Sale in
such country for such Indication:

          (i)  If Licensee, its Affiliates or sublicensees market and sell the
               Product alone, [ * ]of the Net Sales of the Product; and

          (ii) If Licensee, its Affiliates or sublicensees market and sell the
               Product as part of a Kit, [ * ] of the Net Sales of the Kit.

          (iii) Following the termination of the royalty period set forth above
               (i.e., upon the earlier of (x) or (y) above), if (a) any of the
               composition-of-matter patents in Japan covering the Compound
               [ * ] is still enforceable in Japan, and such patent(s) were
               issued and effective as of the Effective Date and remain subject
               to royalty obligations under the Research Agreement and the
               Assignment described in clause (b) below, and the sale of the
               Product in Japan would infringe a Valid Claim of such patent(s)
               absent a license, and (b) if at such time NPC continues to have
               royalty obligations to [ * ], based on gross sales of the Product
               in such countries in the Territory, then, in countries without
               Market Exclusivity, Licensee shall pay Licensor a royalty of
               [ * ] of the gross sales of the Product if Licensee, its
               Affiliates or sublicensees sell the Product alone in countries
               without Market Exclusivity, or (subject to the last sentence of
               this Paragraph (iii)) [ * ] of gross sales of the Kit if
               Licensee, its Affiliates or sublicensees sell the Product as part
               of a Kit in countries without Market Exclusivity, but only until
               the earlier of (a) or (b) above is no longer the case.
               Notwithstanding the foregoing, if during the royalty period in
               which Net Sales of the Kit are calculated under this Paragraph
               (iii), Licensee, its Affiliates or sublicensees also sell the
               Product separately in the same country where they sell the Kit
               for the same Indication, then Licensee shall (when royalties are
               payable under this Paragraph (iii)) pay royalties on all Product
               sold as part of Kits in such country at the rate of [ * ] of
               gross sales during such

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               period (for example, if Licensee sells the Product as part of the
               Kit in Country A for $X per Kit per dose for lung cancer and, in
               the same royalty period, Licensee also sells the Product
               separately for $Y per dose in Country A for lung cancer, Licensee
               shall (with respect to sales of Kits) pay a royalty equal to
               [ * ] times gross sales based on $Y times the number of Kits sold
               in Country A during that royalty period).

     5.3.2 Royalty in Countries Covered by Market Exclusivity. With respect to
all countries in which Market Exclusivity exists for the Product for a given
Indication, Licensee shall pay the following royalty in respect to the Product
and the Kit sold in such country for such Indication for therapeutic application
to human Disease Areas from the date of the First Commercial Sale in such
country:

          (a) Until expiration of such Market Exclusivity:

          (i)  If Licensee or its Affiliates market and sell the Product alone
               (not as part of a Kit), [ * ] of the Net Sales of the Product; if
               sublicensees market and sell the Product alone (not as part of a
               Kit) for therapeutic application in the Oncology Disease Area in
               humans, [ * ] of the Net Sales of the Product; if sublicensees
               market and sell the Product alone for therapeutic application in
               the Ophthalmology Disease Area in humans, [ * ] of the Net Sales
               of the Product; and if sublicensees market and sell the Product
               alone for therapeutic application in other Disease Areas in
               humans other than Oncology and Ophthalmology, the royalty
               percentage set forth in the table at the end of this Section
               5.3.2(a).

          (ii) If Licensee or its Affiliates market and sell the Product as part
               of a Kit, [ * ] of the Net Sales of the Kit; if sublicensees
               market and sell the Product as part of a Kit for therapeutic
               application in the Oncology Disease Area in humans, [ * ] of the
               Net Sales of the Kit; if sublicensees market and sell the Product
               for therapeutic application in the Ophthalmology Disease Area in
               humans, [ * ] of the Net Sales of the Kit; and if sublicensees
               market and sell the Kit for therapeutic application in other
               Disease Areas in humans other than Oncology and Ophthalmology,
               the royalty percentage set forth in the table at

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               the end of this Section 5.3.2(a); provided that, if during the
               royalty period for which Net Sales of the Kit are calculated,
               Licensee, its Affiliates or sublicensees also sell the Product
               separately in the same country where they sell the Kit for the
               same Indication, then Licensee shall pay royalties on all Product
               sold as part of Kits in such country at the rates set forth in
               subsection (a)(i) above during such period (for example, if
               Licensee sells the Product as part of the Kit in the United
               States for $X per Kit per dose for lung cancer and, in the same
               royalty period, Licensee also sells the Product separately for $Y
               per dose in the United States for lung cancer, Licensee shall
               (with respect to sales of Kits) pay a royalty equal to [ * ]
               times Net Sales based on $Y times the number of Kits sold in the
               United States during that royalty period).

             Royalty Percentages Applicable to Sublicensee Net Sales
             of Product for Therapeutic Application in Human Disease
                  Areas Other Than Oncology and Ophthalmology:

<TABLE>
<CAPTION>
 If the gross selling price    Royalty on Net    Royalty on Net
per dose of the Product is:   Sales of Product    Sales of Kit
---------------------------   ----------------   --------------
<S>                           <C>                <C>
-    [ * ]                          [ * ]             [ * ]

-    [ * ]                          [ * ]             [ * ]

-    [ * ]                          [ * ]             [ * ]

-    [ * ]                          [ * ]             [ * ]

-    [ * ]                          [ * ]             [ * ]
</TABLE>

          (b) On and after the date of expiration of such Market Exclusivity and
until the tenth anniversary of the date of the First Commercial Sale in such
country for such Indication:

          (i)  If Licensee, its Affiliates or sublicensees market and sell the
               Product alone, [ * ] of the Net Sales of the Product; and

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          (ii) If Licensee, its Affiliates or sublicensees market and sell the
               Product as part of a Kit, [ * ] of the Net Sales of the Kit.

     5.3.3 Royalties on Net Sales of Product for Other than Therapeutic
Application to Human Disease Areas. Licensee shall pay a royalty on Net Sales of
the Product or the Kit sold for uses other than human therapeutic uses (e.g.,
diagnostic and monitoring uses for human Disease Areas, veterinary uses and
Other Commercial Applications); the amount of such royalty shall be [ * ] of the
royalty rates specified above except for the royalty payable under Section
5.3.1(iii) (such royalty only being due if owed by NPC to PPI's former
shareholders on such Product sales under the Research Agreement and Assignment
described in Section 5.3.1(iii)).

     5.3.4 Extension of Market Exclusivity. If during the term of this
Agreement, (i) Licensor obtains a new patent right covering an invention that,
if used for the Product, would extend Market Exclusivity or create new Market
Exclusivity for the Product in a given Indication in a given country, and (ii)
Licensee notifies Licensor that Licensee elects, in its discretion, to use such
invention for the Product, such patent right shall automatically, upon such
election by Licensee, be included in the Licensed Patents. In such event,
Licensee shall (subject to Sections 5.3.5, 5.3.8 and 5.3.9 below) pay the
royalty on Net Sales of such Product (or a Kit including such Product, as the
case may be) in the Indication and country in which Market Exclusivity is
created or extended by such new patent right at the rate(s) set forth in Section
5.3.2(a) above during the period of such Market Exclusivity (if such Indication
is for therapeutic application to a human Disease Area; otherwise, in accordance
with Section 5.3.3, the royalty shall be [ * ] of such rates during the period
of Market Exclusivity). Unless and until Licensee notifies Licensor that it
elects to use a new patent right as aforesaid, such new patent right shall be
excluded from the Licensed Patents.

     5.3.5 Reduction of Royalties. Royalties payable by Licensee to Licensor
under this Section 5.3 shall be reduced or abated, as the case may be, as
follows:

          (a) In the event of, and only during the pendency of, any third-party
infringement of Licensed Patents, royalties due in the country(ies) of such
infringement shall be reduced to [ * ] of the then currently applicable levels,
provided that the recovery obtained in any action or suit against a third-party
infringer shall be subject to Section 14.3(b).

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          (b) In the event the development, manufacture, use, distribution,
marketing or sale of the Product or the Product as part of the Kit in the
Territory allegedly infringes a third party's patent rights, where the alleged
infringement is based on Licensee's or its Affiliates' or sublicensees' practice
in the Territory of the Licensed Technology, amounts otherwise payable to
Licensor shall be reduced as provided in Section 14.4.

          (c) If a third party obtains, by order, decree or grant from a
competent governmental authority in any country in the Territory, a compulsory
license under Licensed Patents authorizing such third party to manufacture, use
or sell any Product or the Product as part of the Kit in such country, with a
royalty rate lower than the applicable royalty rate set forth in this Article 5,
Licensor or Licensee, as the case may be, shall give the other party prompt
notice of such compulsory license. During the period of sales of such Product
and/or the Product as part of the Kit by said third party under such compulsory
license, Licensee's obligations to pay royalties under Section 5.3 hereof with
respect to sales in such country for such Product and/or the Product as part of
the Kit shall be reduced to the rate payable by said third party under such
compulsory license.

     5.3.6 Quarterly Payments in U.S. Dollars. Royalty payments due under this
Agreement shall accrue on a calendar quarter basis (each calendar quarter being
a "royalty period") and shall be made in U.S. Dollars within [ * ], with respect
to sales by Licensee and its Affiliates, and within [ * ], with respect to sales
by sublicensees, after the last day of March, June, September and December for
royalties accruing on the Net Sales during the preceding royalty period.

     5.3.7 Royalty Statement. Each quarterly royalty payment shall be
accompanied by a statement which sets forth, on a country-by-country basis and
an Indication-by-Indication basis (to the extent such information is readily
available), the gross sales and the Net Sales expressed in U.S. Dollars, the
quantity of the Product and/or the Kit sold, and the royalty rates and royalties
payable. For those Net Sales occurring in currencies other than United States
Dollars, the exchange conversion of foreign payments into U.S. Dollars shall be
calculated at the [ * ] during the royalty period as provided for in Section
5.3.6.

     5.3.8 [ * ] Product and Kit. [ * ] shall be payable in respect of the Net
Sales of a given Product or Kit [ * ] shall be due on the Net Sales of that
Product or Kit to that customer, [ * ].

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     In the event that one formulation of the Product is approved for use with
[ * ] within a Disease Area or for use with [ * ], then the royalty rate and the
term of royalty payments shall be determined in accordance with the following
example: [ * ].

     In addition, if a Product is sold as a part of a Kit, [ * ] -- on Net Sales
of the Kit -- [ * ].

     5.3.9 Sales to Affiliates and Sublicensees. No royalties shall be payable
on sales between and among Licensee, its Affiliates and sublicensees, but shall
become payable upon the first sale by Licensee, its Affiliates and/or
sublicensees to an unrelated third party.

     5.3.10 Records. Licensee shall keep, and cause its Affiliates and
sublicensees to keep, accurate records of sales of Products and Kits made
pursuant to the license granted hereunder so that the royalty payable and the
royalty statement may be verified. Such records shall be open to inspection at
any reasonable time -- but there shall not be more than [ * ] -- within [ * ]
years after the royalty period to which such records relate. Such inspection
shall be by an independent certified public accounting firm selected by Licensor
and approved by Licensee, which approval shall not be unreasonably withheld, and
shall be at Licensor's expense. Such accounting firm shall execute and deliver
to Licensee a confidentiality agreement in a form reasonably acceptable to
Licensee. In no event shall any information, except for the information
necessary for Licensor to confirm the accuracy of the royalty payments, be
disclosed by such accounting firm to Licensor. Such accounting firm shall
disclose the same information to Licensee. If said examination of the records
reveals more than a [ * ] underpayment of the royalty payable during the royalty
period(s) under inspection, expenses for said accounting firm shall be borne by
Licensee.

     5.4 Bank Remittance. All payments under Sections 5.1, 5.2 and 5.3 shall be
made by wire transfer to the bank and to the account designated by NPC on behalf
of Licensor. The allocation of payments between NPC and Meiji shall be solely in
their discretion and solely their responsibility.

     5.5 Late Payments. In the event that any payment under Sections 5.1, 5.2 or
5.3 is not made when due, including any underpayment of royalties determined in

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accordance with Section 5.3.10, [ * ].

     5.6 Taxes and Withholdings. All taxes required to be withheld from any
payments under Article 5 shall be deducted from the amounts payable and shall be
paid to the appropriate fiscal or tax authorities on behalf of Licensor. Such
payments shall be withheld and paid on behalf of NPC unless NPC notifies
Licensee in writing that some or all of such payments should be withheld and
paid on behalf of Meiji. Licensee shall promptly furnish to Licensor (care of
NPC unless Licensee is notified otherwise) tax receipts issued by the
appropriate fiscal or tax authorities evidencing payment of such taxes. Licensor
may seek applicable tax credits in Japan for the amount of such withholdings.

ARTICLE 6. DEVELOPMENT

     6.1 Due Diligence. Licensee shall use commercially reasonable
diligence--consistent with accepted business practices and legal requirements
(which diligence may, but not necessarily will, include application of
scientific, technical, clinical and regulatory personnel, equipment, and time
and resources towards the development of the Product and/or the Product as part
of the Kit to meet Licensee's obligations under this Agreement), and taking into
account issues of commercial viability, safety and efficacy -- to develop,
obtain Regulatory Approval of, and commercialize the Product (and/or, in
Licensee's discretion, the Product as part of a Kit). Licensee's development
efforts with respect to the Oncology and Ophthalmology Disease Areas shall be
guided by the development plan attached hereto as Exhibit B (hereinafter
referred to as the "Development Plan"), but the failure to comply with such
Development Plan shall not be deemed a failure of required diligence if
Licensee's efforts reflect commercially reasonable diligence as described above.
Licensee shall notify Meiji of any material amendment or modification of the
Development Plan and the reasons therefor, and Meiji shall have the right to
offer input and suggestions to Licensee regarding such amendment(s) and
modifications(s); Licensee shall give due consideration to such input and
suggestions, provided that such consideration shall be in accordance with
commercially reasonable diligence as described above. In addition, Licensee
shall use commercially reasonable diligence to achieve the [ * ]. Licensor
recognizes, however, that commercial, safety or efficacy issues may not make it
commercially reasonable to achieve such targets, and that many aspects of
achieving such targets are beyond Licensee's reasonable control. Licensor
further agrees that Licensee's exercise of commercially reasonable diligence
with respect to a Product or a Product as part of a Kit for any one Indication
in a Disease Area shall be deemed to satisfy Licensee's diligence obligations in
such Disease Area.

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Licensor further agrees that, during the first [ * ] months following the
Effective Date of this Agreement, Licensee's exercise of commercially reasonable
diligence in the development of a Product or a Product as part of a Kit in any
one Disease Area shall be deemed to satisfy Licensee's diligence obligations
under this Agreement.

     Provided that it is reasonable to do so on grounds of commercial
non-viability, toxicity or non-efficacy, Licensee shall have the right,
exercised by giving notice in writing to Licensor, either not to commence
development of a Product (including a Product as part of a Kit), or to cease
development of a Product, or not to pursue Regulatory Approval or
commercialization of a Product in one or more Disease Area(s) in a particular
country or countries. In such case, at Licensee's option as indicated in its
notice to Licensor, either (i) the scope of Licensee's rights under the license
granted in this Agreement shall be reduced commensurate with the Disease Area(s)
or countries Licensee elects to relinquish in such notice, or (ii) Licensee may
elect to reduce its license rights in respect to a specified country or
countries or a specified Disease Area or Disease Areas to a "semi-exclusive
license" as described, and on the terms provided, in Section 6.4 below.

     6.2 Compliance with Regulations. Licensee shall undertake development of
the Product and/or the Product as part of the Kit hereunder in accordance with
all applicable regulatory requirements including, but not limited to, the
then-current Good Laboratory Practices, Good Clinical Practices and Good
Manufacturing Practices promulgated by any regulatory authorities in any country
of the Territory.

     6.3 Progress Report. Licensee shall report semi-annually to Licensor on the
progress status of the development work and activities with respect to the
Product and/or the Product as part of the Kit. In addition, at the request of
either Meiji or Licensee, the parties shall meet every six (6) months to discuss
the status of development, at a mutually agreeable time and place.

     6.4 Failure of Due Diligence. In the event that Licensor believes Licensee
has failed to perform in accordance with the diligence obligations with respect
to the development and commercialization of the Product as set forth in this
Agreement, Licensor may, in its discretion, acting through Meiji, give detailed
written notice of such alleged failure to Licensee, such notice to specify the
countries and Disease Area(s) (collectively, the "areas") in which Licensor
believes Licensee has failed to proceed with commercially reasonable diligence.
Licensee and Meiji shall then discuss the situation in good faith. If Licensee
agrees it has not acted with the requisite diligence in the areas indicated in
Licensor's notice, but is willing to do so, it

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shall immediately commence diligent efforts in the areas indicated.
Alternatively, Licensee may, in its discretion, agree to relinquish certain
rights under the license granted in this Agreement, as provided in Section 6.1
above. Alternatively, Licensee may disagree with Licensor and claim that its
efforts reflect commercially reasonable diligence as required in Section 6.1. In
such case, Licensor may agree with Licensee following their discussion or may
disagree with Licensee. If Licensor disagrees with Licensee, Licensor may, in
its discretion (acting through Meiji) initiate a dispute resolution process in
accordance with Section 20.9 and an arbitration proceeding in accordance with
Section 20.10 to resolve the issue.

     If the arbitrators issue a final decision in favor of Licensor on the issue
of diligence, then the following shall be the sole options and remedies
available to the parties:

          (a) Licensee has the option (to be exercised in writing not later than
[ * ] days following Licensee's receipt of the arbitrators' final decision), in
its discretion, of terminating its rights under the license granted in this
Agreement in areas in which the arbitrators found it failed to exercise
commercially reasonable diligence; or

          (b) If Licensee elects, in its discretion, to retain its full,
exclusive rights under this Agreement, Licensee shall (either before or after
the arbitration proceeding, but not later than [ * ] following its receipt of
the arbitrators' final decision) pay [ * ]. If Licensee continues to elect to
retain its full rights under this Agreement, it shall pay [ * ], whichever is
earlier. Upon Licensee's payment of the total first milestone payment due in a
given Disease Area, Licensee shall be deemed to have satisfied its diligence
obligations under this Agreement in such Disease Area, and Licensor shall
thereafter have no right or ability to allege or contest Licensee's lack of
diligence in such Disease Area.

          (c) If Licensee elects not to avail itself of either option described
in Paragraph (a) or Paragraph (b) above, then Licensor shall have, as its sole
remedy for Licensee's failure to exercise the requisite diligence, the option
(to be exercised in writing between [ * ] and [ * ] days following Meiji's
receipt of the arbitrators' final decision, if Licensee did not elect either of
its options above) to convert the exclusive license granted to Licensee under
this Agreement into a semi-exclusive one in respect to a country or countries
and a Disease Area or Disease Areas with respect to which the arbitrators
concluded Licensee's failure of commercially reasonable diligence occurred;
provided that if the arbitrators conclude both (a) that

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Licensee is not diligently developing the Product at all, in any Disease Area,
and (b) that Licensee is at that time developing a competing product in a given
Disease Area, then Licensor, acting through Meiji, may in its discretion (to be
exercised in writing between [ * ] and [ * ] days following Meiji's receipt of
the arbitrators' final decision if Licensee did not elect either of its options
above) terminate (rather than merely convert to semi-exclusive) Licensee's
license rights under this Agreement in the Disease Area in which Licensee is
developing a competing product. (For the avoidance of doubt, and without
limiting the above, this Agreement does not prohibit Licensee from developing
and commercializing other products in the Field.)

     The term "semi-exclusive license" shall mean that Licensee shall retain the
exclusive license granted to it under this Agreement, with the right to
sublicense, subject to the reservation of the same right by Licensor (including
the right to manufacture Compound and Bulk and make, use and sell Product), but
only in the country(ies) and Disease Area(s) in which Licensee failed to
exercise the required diligence, with the right to license (subject to
Licensee's semi-exclusive license). In such case, Licensee's right to sublicense
and Licensor's right to license, as applicable, means only the right to
sublicense or license, as the case may be, all of the granted rights under
Article 2 or the reserved rights under this Section 6.4 to one third party each
(for a total of two) in a particular country relating to the Disease Area(s) in
question. In the event of such sublicense or license, Licensee and Licensor
shall each have no right itself to exercise the right granted under Article 2 or
reserved under this Section 6.4 in such particular country for the Disease
Area(s) in question, as the case may be (for the sake of clarification, this
means that, in the event of a semi-exclusive license, each party will have the
right itself, or through an Affiliate or one sublicensee (in the case of
Licensee) or through an Affiliate or one licensee (in the case of Licensor), to
make, use and sell the Product relating to the Disease Area in question in a
given country). If Licensee's exclusive license is converted into a
semi-exclusive one as to a Disease Area in a country, then the royalty rates set
forth in Section 5.3 shall be [ * ] in respect to Net Sales of Product in such
Disease Area in such country for which the option is exercised, except in those
country(ies) where Licensor elects never to undertake the development,
Regulatory Approval or commercialization of the Product (itself or through an
Affiliate or a licensee). In the event Licensee's license is converted to
semi-exclusive in a Disease Area in a country, Licensee shall consent to
Licensor cross-referencing Licensee's IND for such Disease Area in such country,
free of charge.

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     6.5 Licensee Information. Licensee shall own all resulting Licensee
Information, data, reports and other information and all rights arising from its
research, development, regulatory and commercialization activities and efforts
including, but not limited, to all data, reports, information and rights arising
out of any NDA for a Product or Kit, any FDA approval thereof or any
corresponding application or approval in any country in the Territory.

     6.6 Transfer of IND. NPC has an IND with the FDA for the Product (IND No.
[ * ]. Promptly after Licensor's receipt of the Upfront License Fee specified in
Section 5.1 (unless due to unavoidable translation problems), Licensor shall
complete the tasks assigned to it and submit the specified materials to Licensee
in accordance with Exhibit C (IND Transfer to Light Sciences). NPC shall
transfer the IND and all of NPC's rights and responsibilities in such IND to
Licensee. Such transfer shall be substantially in the form as set forth in
Exhibit C. Provided Licensor complies with its obligations in accordance with
Exhibit C, all subsequent work necessary to make such IND fully compliant with
applicable laws and regulations, and to enable Licensee to conduct further
development thereon, shall be at Licensee's sole responsibility and cost.

ARTICLE 7. REPORTS OF ADVERSE EVENTS

     Promptly after the Effective Date, and from time to time thereafter at
either party's request, the parties hereto shall discuss and establish standard
operating procedures for the prompt exchange -- in compliance with all
applicable laws and regulations -- of any and all information on serious and
other adverse drug experiences, as defined and required by the FDA and other
applicable regulatory authorities, which the parties are obligated to report to
any regulatory authorities in accordance with applicable regulations or
requirements in connection with any use of the Compound and/or the Product. Each
party shall comply with such agreed procedures. Without limiting the foregoing,
each party shall immediately provide to the other party a copy of any adverse
event report(s) of which it becomes aware during the term of this Agreement, so
long as the other party is developing or marketing the Product.

ARTICLE 8. SUPPLY OF THE BULK AND PRODUCT BY MEIJI

     8.1 Bulk Supply.

          (a) Development Phase

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          (i)  In order to enable Licensee to proceed with development of the
               Product without disruption, Meiji shall, as requested by
               Licensee, supply Licensee with up to [ * ] of the Bulk in the
               year 2000 and [ * ] of the Bulk in the year 2001 for the
               development of the Product. [ * ].

          (ii) The procedures and time periods for forecasting, ordering,
               delivery and acceptance of the Bulk to be supplied for the
               development use under (i) above are set forth in Section 8.5
               below. It is understood and agreed that there shall be no minimum
               batch size for orders of the Bulk.

          (iii) Price of the Bulk to be supplied for the development use under
               (i) above shall be [ * ]; provided that Meiji shall supply the
               [ * ].

          (b) Commercialization Phase. If Licensee requests Meiji to supply the
Bulk during the period of Product commercialization, Meiji shall do so, subject
to the terms and conditions of a separate supply agreement to be negotiated in
good faith and executed at the time of such request by Licensee. Such separate
agreement shall be consistent with the applicable terms of the Agreement, will
contain commercially reasonable terms and conditions as are necessary and
appropriate for such a supply agreement, and shall incorporate the following
terms among others: (x) Licensee shall pay not less than [ * ] for the first
[ * ] of the Bulk supplied each year for commercial use, and (y) if Licensee
requests more than [ * ] per year, the separate agreement shall assure the price
of the Bulk not less than [ * ] and compensation to Meiji for its capital
investment (if any) necessary to increase its manufacturing capacity to supply
Licensee's requirements. Unless such separate agreement is executed by the date
of the First Commercial Sale of Product in the United States or Europe,
whichever is earlier, Meiji shall have no subsequent obligations to supply the
Bulk for commercial use.

     8.2 Product Supply. If requested by Licensee, Meiji shall supply the
Product for the development use during the Phase I Clinical Studies for the
first Product and - but only if reasonably necessary to prevent disruption of
Product development - the Phase II Clinical Studies for the first Product (for
the avoidance of doubt, Phase II Clinical Studies are not Pivotal Clinical
Studies). Meiji shall not supply the Product to Licensee thereafter. Licensee
shall use the Product supplied by Meiji hereunder solely for the purpose of the
development specified herein and shall

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not use the same for any other purposes. Price of the Product per vial of 100 mg
active Compound to be supplied for the development use hereunder shall be [ * ]
and all orders for the Product (except for the [ * ]) shall call for each
shipment to be in quantities of [ * ] as a unit; provided that Meiji shall
supply the [ * ] of Product to Licensee [ * ]. The procedures and time periods
for forecasting, ordering, delivery and acceptance of the Product are set forth
in Section 8.5 below.

     8.3 Room Temperature Stability Studies. Promptly after receipt of the
Upfront License Fee specified in Section 5.1, [ * ].

     8.4 Compliance With Specifications.

          8.4.1 Audit. Prior to commencement of supply of the Bulk and/or the
Product by Meiji to Licensee as provided hereunder, Licensee shall audit Meiji's
manufacturing facilities during reasonable business hours to verify that Meiji's
facilities, equipment and procedures are acceptable to Licensee in its quality
assurance and production standards.

          8.4.2 Meiji Responsibility for Compliance With Specifications,
Including cGMP. In the event that, as the result of such audit under 8.4.1
above, Licensee accepts and requires Meiji to supply the Bulk and/or the
Product, Meiji shall supply the Bulk and/or the Product in accordance with this
Article 8. Meiji shall use its best efforts promptly to remedy any plant
deficiencies or manufacturing problems brought to Meiji's attention by Licensee,
the FDA or any foreign counterparts of the FDA in Europe and to maintain all of
its manufacturing facilities for supply of the Bulk and the Product to Licensee
in compliance with the then-current U.S. Good Manufacturing Practices (cGMP) and
any other comparable regulations or guidelines in Europe. The Bulk and Product
Meiji supplies to Licensee (or its designees) shall conform in all respects to
the then-current agreed Specifications for such Bulk and Product, including
cGMP, and Meiji will manufacture such Bulk without negligence or fault,
including without contamination or adulteration. As used in this Section 8.4.2,
"Bulk" means NPe6 or ME2906 itself in bulk form, and "Product" means any
formulation containing NPe6 or ME2906 itself as an active ingredient in finished
form.

     8.5 Forecasting, Orders, Delivery and Acceptance.

          8.5.1 Forecasting and Ordering of Supply for Development. Subject to
the limitations in Sections 8.1(a) and 8.2 above, Meiji shall supply Licensee
with such quantities of the Bulk and/or Product as Licensee may order pursuant
to this

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Agreement. Promptly after the Effective Date and thereafter, no later than [ * ]
days before the start of each Half-Year Period, Licensee shall provide Meiji
with a rolling [ * ] quarter forecast of its expected requirements of the Bulk
and/or Product, including forecast quantities and delivery dates. Licensee shall
update such forecast at the beginning of each calendar quarter thereafter during
the development phase. No later than [ * ] days before the first day of any
calendar month in which delivery is required (a "Delivery Month"), Licensee
shall provide to Meiji its firm purchase orders for Bulk and/or Product for
development use, including quantities and delivery dates. Such orders shall not
deviate by more than [ * ] percent from the amount forecasted for such delivery
dates in the most recent forecast. Meiji shall use its best efforts to deliver
the ordered quantities to Licensee during the specified Delivery Month, at
facilities designated by Licensee, no later than [ * ]days after receipt by
Meiji of Licensee's firm order for a specified quantity of the Bulk and/or
Product. The actual date of delivery to Licensee within each specified Delivery
Month shall be within the discretion of Meiji, and Licensee shall undertake to
accept delivery on such delivery date. Notwithstanding the foregoing, Meiji
shall delivery to Licensee the first [ * ] of Bulk (referenced in Section
8.1(a)(iii)) within [ * ] days after Licensee pays the Upfront License Fee
(unless Licensee and Meiji agree on a different delivery date), and Meiji shall
deliver to Licensee the first [ * ] of Product (referenced in Section 8.2) in
[ * ] (unless Licensee and Meiji agree on a different delivery date, in order to
enable Product development to proceed without disruption. As used herein,
Half-Year Period shall mean the period from April 1 to September 30 in any year
or the period from October 1 in one year to March 31 in the following year, as
the case may require.

          8.5.2 Shipment of Bulk and Product for Development. Meiji shall ship
all Bulk and Product ordered by Licensee to a U.S. port designated by Licensee,
with all expenses associated with shipping, delivery and insurance to be paid by
Licensee.

          8.5.3 Payment. Licensee shall pay Meiji for the Bulk and/or Product it
orders from Meiji within the later of [ * ] days following (i) Licensee's
receipt of Meiji's invoice therefor or (ii) Licensee's receipt of the ordered
Bulk and/or Product at its facilities. Any payment not made when due [ * ].

          8.5.4 Acceptance. Licensee and Meiji shall reasonably agree upon
applicable written specifications, including production criteria in compliance
with cGMP (collectively, "Specifications") for the Bulk and Product. Meiji shall
manufacture and supply all Bulk and Product in accordance with such
Specifications and shall deliver a Certificate of Analysis (in a mutually
agreeable form) with each

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shipment, which certificate shall confirm that the Bulk and Product are in
compliance with the Specifications on the date of shipment. Licensee shall
inspect all shipments of the Bulk and Product supplied by Meiji promptly upon
receipt, and Licensee may, by giving written notice to Meiji, reject any
shipment (i) which does not conform to the applicable Specifications or (ii)
which otherwise is deficient with respect to the quantity or quality of material
provided or due to contamination by materials not listed in the Specifications
or which is adulterated or misbranded (collectively, is "Deficient"). Any such
notice shall be in writing and shall indicate the reasons for such rejection. In
order to reject delivery of a shipment of the Bulk or Product, Licensee shall
give written notice to Meiji of Licensee's rejection of any delivery within
[ * ] days after receipt of such delivery at Licensee's designated facilities
(arrival at the port designated by Licensee shall not constitute delivery to the
facilities designated by Licensee). If Meiji is satisfied that the relevant
shipment does not comply with the Specifications or is Deficient, Licensee shall
dispose of the noncomplying shipment as Meiji shall lawfully direct and, at
Meiji's sole cost and expense, Meiji shall replace the shipment or remedy the
deficiency as soon as practically possible, at its sole cost and expense. If
Meiji disputes Licensee's rejection of such Bulk or Product, the parties shall
submit such Bulk or Product to a mutually agreed third-party laboratory in the
U.S. for testing. Such laboratory's determination shall be final. The party
against whom the third-party laboratory rules shall bear all costs of the
third-party testing. In the event that the third-party laboratory determines
that such Bulk or Product fails to meet the Specifications or is Deficient,
Meiji shall replace such Bulk or Product or remedy the deficiency as soon as
practically possible after receiving the third-party laboratory's notice of such
determination. If the third-party laboratory rules that the rejected Bulk or
Product meets the Specifications and is not Deficient, Licensee shall purchase
such Bulk or Product at the agreed-upon price. If Licensee sends no such notice
of rejection to Meiji, Licensee shall be deemed to have accepted such delivery
[ * ] days after receipt of the shipment at its facilities. Once Licensee
accepts shipment of the Bulk or Product, Licensee shall have no recourse against
Meiji if such Bulk or Product is subsequently deemed unsuitable for use, unless
Licensee proves that the aforementioned qualitative faults could not have been
detected within such period using mutually agreed quality control and acceptance
procedures.

     8.6 Term of Supply Obligation. [ * ].

ARTICLE 9. SALES AND PROMOTION

     9.1 Commercial Sale. Subject to the acknowledgement in Section 9.2

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below, Licensee (including its Affiliates, sublicensees and distributors) shall
commence marketing and sale of the Product and/or Kit in each country of the
Territory as soon as commercially reasonable following the date when all the
necessary Regulatory Approvals to market and sell the Product and/or Kit are
obtained from the regulatory authorities in such country. Licensee shall
promptly notify Licensor of the respective dates when the Regulatory Approvals
are obtained and the commercial sale of the Product and/or Kit is commenced in
each country of the Territory.

     9.2 Sales Promotion. Licensee (including its Affiliates, sublicensees and
distributors) shall use commercially reasonable efforts to promote and
commercialize the Product and/or the Kit in the Territory; provided that
Licensor acknowledges that potential market size or financial, pricing or
regulatory conditions in certain countries may make it commercially unreasonable
to commercialize Product in such countries, and that it will be commercially
reasonable for Licensee to promote and commercialize Product in certain
countries before other countries.

     Licensee shall promote, at its own expense, sales of the Product and/or the
Kit efficiently and in commercially reasonable fashion by distributing
scientific literature and samples, by advertising in professional publications,
etc., by detailing doctors, hospitals, etc. and by other commercially reasonable
means.

     9.3 Supply of Promotional Materials. Licensee shall furnish Licensor with
copies of its representative promotional materials and packages used for the
Product and/or the Kit for Licensor's reference.

     9.4 Packaging Reference. Where commercially appropriate and in compliance
with applicable laws and regulations, Licensee shall indicate in writing on the
secondary Product packaging (i.e. the unit carton), labels, packages, package
inserts, and promotional materials for the Product, in wording previously
approved in writing by Licensor, that the Product contains Compound developed
and sold under license from Meiji and NPC.

ARTICLE 10. ANTI-INFECTIVES: MEIJI RIGHT OF FIRST NEGOTIATION

     In the event that Licensee or its Affiliates desire to develop the Product
for use in the field of anti-infectives, Licensee shall, prior to implementing a
plan for such development, present a proposal to Meiji for a worldwide
relationship in such field (exclusive of Japan). Meiji shall have a period of
[ * ] days from its receipt of such proposal in which to accept or decline such
proposal. If Meiji declines (or fails

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to accept) such proposal within such [ * ] day period, Licensee, its Affiliates
or sublicensees (by themselves or in collaboration with one or more third
parties) shall be free to develop and commercialize the Product throughout the
Territory for use in the field of anti-infectives, free of any obligations to
Meiji under this Article 10, subject only to the terms and conditions set forth
elsewhere in this Agreement, including payment of the applicable milestone and
royalty payments to Licensor set forth in Sections 5.2 and 5.3 hereof. If Meiji
accepts such proposal within the [ * ] day period, Licensee and Meiji shall
promptly negotiate an appropriate agreement setting forth detailed terms and
conditions to implement such proposal. If the parties fail to execute such
agreement within [ * ] days thereafter, Licensee, its Affiliates or sublicensees
shall be free to develop and commercialize the Product throughout the Territory
for use in the field of anti-infectives, with no obligation to Meiji under this
Article 10, subject only to the terms and conditions set forth elsewhere in this
Agreement.

ARTICLE 11. LICENSEE'S DEVICE

     If Licensee develops or acquires rights to the Device, and if Licensee has
the right and authority to grant the following rights in the Device to Meiji,
Meiji shall have the right, subject to mutual agreement on the terms and
conditions thereof, to develop and customize the Device, and to be the exclusive
distributor (with the right to use subdistributors) of the Device, solely in
Japan and solely in conjunction with the Product. Such terms and conditions,
including Meiji's payment obligation to Licensee in connection therewith and its
obligation to disclose improvements to the Device to Licensee, shall be subject
to discussion and mutual agreement by the parties. When Licensee has developed
or obtained rights to the Device, by itself or through its Affiliates, licensees
or sublicensees, Licensee shall inform Meiji thereof so that Meiji may, in its
discretion, notify Licensee whether Meiji is interested in obtaining rights to
the Device for use with the Product in Japan. If so, Meiji shall present a
written proposal to Licensee, which the parties shall then promptly discuss. If
the parties do not execute an agreement within [ * ] days after Licensee invites
Meiji to present such a proposal, Licensee shall have no further obligation to
Meiji under this Section or otherwise with respect to the Device (except for
royalty obligations under this Agreement based on Net Sales of the Kit). Meiji
recognizes that in the course of developing the Device, obtaining rights to the
Device (or components thereof) from others or contracting with others for the
development of the Device, Licensee may not have, or may lose, the right to
grant Meiji the rights contemplated in this Section, in which case Meiji shall
have no rights hereunder, provided that Licensee shall use reasonable efforts,
at no cost to Licensee, to obtain

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the right to grant Meiji the rights contemplated in this Section. For the
avoidance of doubt, this Section contemplates Licensee's grant to Meiji of
rights to the Device solely in Japan and solely in conjunction with the Product;
Licensee is free to grant rights to the Device to others for use in Japan in
conjunction with products other than the Product.

ARTICLE 12. PRODUCT LIABILITY AND INDEMNIFICATION

     12.1 Licensor's Indemnification of Licensee. In addition to, and without
limiting, Meiji's indemnification obligations under Section 12.3 and Licensor's
obligations under Section 14.4, Licensor shall [ * ].

     12.2 Licensee's Indemnification of Licensor. In addition to, and without
limiting, Licensee's indemnification obligations under Section 12.3 and
Licensee's obligations under Section 14.4, Licensee shall [ * ].

     12.3 Indemnification Obligations with respect to Bulk and Product Supplied
by Meiji. Subject to, and without limiting, Licensor's obligations under
Sections 12.1 and 14.4, during and after the term of this Agreement, Licensee
shall [ * ].

ARTICLE 13. TRADEMARKS

     Licensee and its Affiliates and sublicensees may use any trademark(s) owned
or controlled by Licensee or any of its Affiliates or sublicensees in connection
with the Product and/or Kit to be distributed in the Territory, and shall notify
Licensor in writing of the same. Licensor shall have no ownership or other right
in or to such trademark(s).

ARTICLE 14. PATENTS

     14.1 Patent Maintenance. Licensor shall, at its sole cost and expense, use
diligent efforts to prosecute, obtain and maintain all Licensed Patents in the
Territory. Licensor shall promptly notify Licensee in writing of the filing or
issuance of any Licensed Patents. In addition, on an ongoing basis during the
term of this Agreement, Licensor shall provide to Licensee [ * ].

     14.2 Extension of Licensed Patent Term. Upon the written request of
Licensee, and with Licensee's reasonable cooperation, Licensor shall execute and
file any appropriate application and related documents to extend the term of any
Licensed Patent.

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     14.3 Third-Party Infringement of Licensed Patents.

          (a) Each party shall promptly notify the other party if it becomes
aware of the activities of any third party which are believed to infringe any of
the Licensed Patents.

The parties, including their Affiliates and sublicensees as appropriate, shall
consult as to a potential litigation strategy or strategies against the alleged
infringer and shall use reasonable efforts to terminate such alleged
infringement without litigation.

          (b) If the efforts of the parties are not successful in abating the
alleged infringement, Licensee shall have the first right, but not the
obligation, to bring an appropriate suit or action against such infringement,
[ * ].

     14.4 Alleged Infringement of Third-Party Patents.

          (a) Resolution of Alleged Infringement Through Third-Party License. In
the event either Licensor or Licensee learns of any third party's patents which
may cover the development, manufacture, use, distribution, marketing or sale of
the Product and/or the Product as part of the Kit in the Territory, and such
coverage arises out of Licensee's practice, in the Field and in the Territory,
of its rights granted by Licensor hereunder, such party shall notify the other.
The parties shall confer in good faith regarding such potential infringement
risk and shall explore reasonable alternatives for avoiding such risk. Unless
the parties mutually agree on a different strategy to avoid the risk, and if
Licensee believes in good faith that the manufacture, use or sale of the Product
would create an unjustified risk of infringement liability, Licensee may
negotiate and enter into a license for such third party's patents. Licensee
shall pay any royalties that may be due by Licensee under such third-party
license. Provided that Licensee has obtained Licensor's prior written consent to
such third-party license, which consent Licensor shall not unreasonably withhold
or delay, Licensee may credit and offset [ * ] of the amount of royalties due
for such third-party license against any subsequent royalty payments owed to
Licensor hereunder (for the sake of clarification, such credit and offset shall
not be applicable to royalties paid to Licensor prior to such third-party
license); provided that, in no event may Licensee reduce the amount owed to
Licensor by more than [ * ] of any royalty payment owed to Licensor in any
calendar quarter, and any unused credit may carry forward to be used as a credit
against future royalty payments due to Licensor hereunder so long as any portion
of such credit remains unused.

          (b) Defense of Action for Alleged Infringement. Additionally, if a

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third party files a claim, suit or action (collectively, an "Infringement
Claim") against Licensee or any of its Affiliates or sublicensees claiming that
any patent owned or controlled by a third party is infringed by the development,
manufacture, use, marketing, distribution or sale of the Product and/or the
Product as part of the Kit, and any such Infringement Claim arises out of
Licensee's or any of its Affiliates' or sublicensees' practice in the Field in
the Territory of any Licensed Technology licensed hereunder, [ * ].

          (c) Where Licensee Is Unable to Continue Product Sales Because of
Infringement Claim. In the event Licensee, its Affiliates or sublicensees shall
not be able to continue to sell the Product any longer in the country(ies) or
Disease Areas that were the subject of the Infringement Claim due to such
Infringement Claim, [ * ].

          (d) Licensor's Obligations Where Licensee is Able to Continue Product
Sales. In the event Licensee, its Affiliates and sublicensees shall be able to
continue to sell the Product despite such Infringement Claim, Licensee shall
[ * ].

          (e) Licensor's Sole and Exclusive Obligations. Except for, and without
limiting, Licensor's obligations under Sections 12.1 and 19.1, Licensor's
obligations to Licensee set forth in this Section 14.4, and Licensee's rights
under this Section 14.4 [ * ] with respect to the alleged infringement of
third-party patents by Licensee, its Affiliates and sublicensees.

ARTICLE 15. INVENTIONS

     15.1 Licensee's Inventions. All improvements and inventions made by
Licensee pertaining to the Compound, the Product and/or the Kit shall be owned
solely by it, and Licensee shall have the right to control the filing,
prosecution and maintenance of all patents on such inventions worldwide at its
own expense. So long as Meiji is developing and commercializing the Product in
Japan, and provided that Licensee at such time has the right and authority to
make the following disclosures to Meiji and to grant the following rights to
Meiji, Licensee shall promptly disclose to Meiji in writing all improvements and
inventions relating to the Compound, the Product and the Product part of the Kit
in sufficient detail to allow Meiji to evaluate them (excluding any improvements
and inventions relating to the manufacture of the Compound, the Bulk and/or the
Product). Meiji shall have the right to use non-patentable improvements
(excluding those relating to (i) the manufacture of the

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Compound, the Bulk and/or the Product and (ii) Other Commercial Applications),
[ * ], solely in connection with Meiji's development and sale of the Product in
Japan in the Field. Meiji shall have the right of first negotiation to obtain an
exclusive license, with the right to sublicense, to exercise (a) patentable
improvements and inventions relating to the Compound, the Product and the
Product part of the Kit (excluding those relating to the manufacture of the
Compound, the Bulk and/or the Product), and (b) patentable and non-patentable
inventions and improvements relating to Other Commercial Applications during the
term of this Agreement in Japan in connection with Meiji's development and sale
of the Product in Japan in the Field. In the event that Licensee has filed
patent application(s) on such inventions and improvements, Licensee shall notify
Meiji of the identity of such patent application(s) and a summary of the
inventions and improvements claimed therein. Thereafter, Licensee shall, if
requested by Meiji, inform Meiji of the prosecution status of such patent
application(s). If Meiji expresses an interest in any such improvement or
invention, Meiji shall present the proposed terms and conditions of an exclusive
license to Licensee to practice such improvement or invention in connection with
the Product in Japan during the term of this Agreement. If Licensee accepts such
proposal within [ * ] days of its receipt of such proposal, Meiji and Licensee
shall promptly negotiate an appropriate agreement setting forth detailed terms
and conditions to implement such proposal. If the parties fail to execute such
agreement within [ * ] days thereafter, Licensee shall have no further
obligation to Meiji with respect to such invention or improvement.

     15.2 Licensor's Inventions. All improvements and inventions made by
Licensor pertaining to the Compound or Product shall be owned solely by
Licensor, subject to this Agreement. Licensor shall have the right to control
the filing, prosecution and maintenance of all patents on such inventions
worldwide at its own expense. Licensor shall promptly disclose to Licensee in
writing all improvements and inventions pertaining to the Compound or Product in
sufficient detail to allow Licensee to evaluate them (excluding any improvements
and inventions relating to the manufacture of the Compound, the Bulk and/or the
Product that Licensor develops during the term of this Agreement, after the
Effective Date). Except as provided below in this Section 15.2, such
improvements and inventions developed by Licensor (excluding any improvements
and inventions relating to the manufacture of the Compound, the Bulk and/or the
Product) shall, if desired by Licensee in its discretion, be included within the
scope of Licensed Technology under this Agreement and are and shall be
automatically included within the scope of the exclusive license granted by
Licensor to Licensee in this Agreement, [ * ], but subject to the terms and

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conditions of this Agreement. In the event that Licensor has filed patent
application(s) on such inventions and improvements, Licensor shall notify
Licensee of the identity of such patent application(s) and a summary of the
inventions and improvements claimed therein. Thereafter, Licensor shall, if
requested by Licensee, inform Licensee of the prosecution status of such patent
application(s).

     Notwithstanding the above, if Licensor's improvement or invention does not
pertain to the treatment, monitoring or diagnosis of a Disease Area (human or
animal) but, instead, pertains to an Other Commercial Application, then Licensee
shall not be entitled automatically to include such improvement or invention
within the scope of Licensed Technology licensed under this Agreement; instead,
Licensee shall have a right of first negotiation to obtain an exclusive license
to such improvement or invention in the Territory. After Licensor has disclosed
such improvement or invention to Licensee in sufficient detail to allow Licensee
to evaluate it, and Licensee has had [ * ] days to evaluate such improvement or
invention, Licensee shall notify Licensor whether Licensee is interested in
obtaining license rights to such improvement or invention in connection with the
development and sale of the Product and/or Kit in the Territory in the field
during the term of this Agreement. If so, Licensee shall present a written
proposal to Licensor, which the parties shall then promptly discuss. If the
parties do not execute an agreement for such improvement or invention within
[ * ] days after Licensor receives Licensee's proposal, Licensee shall have no
further rights to such improvement or invention.

     15.3 Joint Inventions. All Inventions made jointly by employees or agents
of each party pertaining to the Compound or the Product shall be jointly owned
(the "Joint Inventions), all as determined in accordance with U.S. laws of
inventorship. With respect to all Joint Inventions relating to the treatment,
diagnosis or monitoring of any Disease Area in humans or animals: (i) Licensee
shall have the exclusive right (with the right to license and sublicense), and
Licensor hereby grants such right to Licensee, without any additional payment to
Licensor, to practice and use the Joint Inventions in the Territory, and shall
have the right to file, prosecute, maintain and control, at its expense, any
patent applications on the Joint Inventions in the Territory; and (ii) Licensor
shall have the exclusive right, with the right to license and sublicense, and
Licensee hereby grants such right to Licensor, without any payment to Licensee,
to practice and use the Joint Inventions in Japan, and shall have the right to
file and control, at its expense, any patent applications on such Joint
Inventions in Japan. With respect to Joint Inventions related to Other
Commercial Applications, the parties shall discuss in good faith the
development, intellectual property protection and commercialization of such
inventions, and their rights and responsibilities with

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respect thereto. Each party shall execute such further documents and take such
further steps as the other party reasonably determines may be necessary or
desirable to effectuate the purposes of this Section.

ARTICLE 16. TERM AND TERMINATION

     16.1 Term. The term of this Agreement shall commence on the Effective Date
and shall extend until, and expire upon, the later of (a) [ * ] or (b), on a
country-by-country basis in the Territory, the expiration, lapse, cancellation,
abandonment or invalidation of the last to expire of the Licensed Patents
covering the Product; provided that if, but for such expiration of the
Agreement, Licensee would remain obligated, on a country-by-country basis, to
pay royalties under Section 5.3, then the Agreement shall continue in effect in
such countries until Licensee no longer remains obligated to pay such royalties,
and shall expire in such countries at such time. [ * ].

     16.2 Termination by Mutual Agreement. The parties may at any time terminate
this Agreement by mutual written agreement executed by Licensor and Licensee.

     16.3 Breach. Either Licensor or Licensee may, in addition to any other
remedies available to it at law or in equity (subject to the terms and
conditions of this Agreement), terminate this Agreement based on the other
party's unremedied breach of a material provision of this Agreement, as provided
in, and in accordance with the procedures set forth in, this Section 16.3. In
the event Licensor or Licensee alleges that the other party has breached a
material provision of this Agreement, it shall give detailed written notice
specifying the alleged breach to the other party, which notice shall, if it is
intended to be a basis for termination, state such intention to the alleged
breaching party if the breach is not cured. If the alleged breaching party fails
to cure its breach of a material provision of this Agreement within [ * ] of its
receipt of such notice, or if such breach is incapable of cure within s[ * ]
period and the alleged breaching party fails to commence diligent and reasonable
steps to cure such breach within such [ * ] period and to continue such steps
diligently thereafter until the breach is cured, then the other party shall have
the right to terminate this Agreement in full upon a further [ * ] written
notice; provided, that should the alleged breaching party dispute in writing the
alleged breach or allege that it has cured the breach or commenced diligent and
reasonable steps to cure such breach within such [ * ] period, the dispute shall
be resolved through the dispute resolution and arbitration process as provided
in Sections 20.9 and 20.10. In the case of such a

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dispute, the termination of this Agreement shall not take effect unless and
until the Agreement is terminated by mutual agreement pursuant to Section 16.2
or by a final decision of the arbitrators pursuant to Section 20.10, which
decision finds that the alleged breaching party has breached a material
provision of this Agreement and failed to cure, and to take reasonable steps to
cure, such breach. Such arbitration proceeding shall be deemed commenced by the
party alleging the breach and seeking to terminate this Agreement. This Section
16.3 shall not apply to the alleged failure of Licensee to proceed with
diligence in the development and commercialization of the Product; the process
and remedy for dealing with such alleged failure is set forth in Section 6.4.

     16.4 Insolvency or Bankruptcy. Either of Licensor (as to Licensee) and
Licensee (as to Meiji or NPC) may, in addition to any other remedies available
to it at law or in equity (subject to the terms and conditions of this
Agreement), terminate this Agreement by written notice to the other party in the
event (where Licensee is the other party) of the commencement of a bankruptcy
proceeding by or against Licensee under the United States Bankruptcy Code, or
(where Meiji or NPC is the other party) of the commencement of an equivalent
proceeding by or against Meiji or NPC under Japanese law, which proceeding seeks
the liquidation, dissolution or winding-up of Licensee, Meiji or NPC, as the
case may be; provided that such proceeding continues unabated for at least [ * ]
days following its commencement; and provided further that the continuation and
success of such proceeding will render the affected party unable to fulfill its
obligations under this Agreement.

     16.5 Serious Events. Should there occur serious or unexpected events or
circumstances which, from a reasonable pharmaceutical company's point of view,
would make it impossible, impracticable or commercially unreasonable to pursue
the development and commercialization of the Product, such as (without
limitation) safety issues, efficacy issues, regulatory issues or other
justifiable reasons which would have a material adverse effect on the
development and commercialization of the Product, Licensee may, in its sole
discretion, but in consultation with Licensor, terminate this Agreement by
written notice to Licensor, such notice to be effective on its receipt.

     16.6 Effect of Termination.

          (a) Upon termination of this Agreement in accordance with Sections
16.2 or 16.5 or by Licensor in accordance with Sections 16.3 or 16.4:

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<PAGE>

          (i)  All rights and licenses granted to Licensee hereunder, including
               the license to develop, use, manufacture and sell the Compound,
               the Bulk and the Product, shall immediately terminate and shall
               revert to Licensor, provided, however, that Licensee may, in its
               discretion, continue to sell its remaining inventory of the Bulk
               and the Product for [ * ] from the effective date of such
               termination, subject to the royalty payment on the Net Sales
               generated by such sales in accordance with Section 5.3; and;

          (ii) Licensee shall, in accordance with Licensor's instruction, return
               to Licensor, or destroy, all the Licensed Know-How and any other
               Confidential Information supplied by Licensor in tangible form
               and copies thereof then possessed by Licensee, its Affiliates and
               sublicensees and the Third-Party Manufacturer(s); and cease all
               use of the Licensed Know-How and any other Confidential
               Information disclosed by Licensor, except to the extent, at the
               time of such termination, the Licensed Know-How and any other
               Confidential Information disclosed by Licensor, is no longer
               Confidential Information (other than due to a breach of Article
               18 by Licensee); and

          (iii) In the event of termination by Licensor under Section 16.3 based
               on Licensee's unremedied breach of a material provision
               hereunder, or termination by Licensor under Section 16.4,
               Licensee shall transfer to Meiji or NPC, as Licensor directs
               [ * ], any Regulatory Approvals (including IND's) or applications
               for Regulatory Approvals (including IND's) for the Product in the
               Territory, together with the Licensee Information and the full
               dossier and all data submitted in support of such Regulatory
               Approvals (including, IND's), excluding any Regulatory Approvals
               pertaining to the Device, applications therefor, and data and
               information related thereto.

          (b) Upon termination of this Agreement by Licensee pursuant to Section
16.3 or 16.4:

          (i)  All rights of Licensor to use or reference any Licensee

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<PAGE>

               Information, or any Licensee invention, improvement or Device,
               and any other Confidential Information disclosed by Licensee
               hereunder, shall immediately terminate; and

          (ii) Licensor shall, in accordance with Licensee's instruction, return
               to Licensee, or destroy, all such Licensee Information,
               information related to Licensee inventions, improvements or the
               Device, and any other Confidential Information disclosed by
               Licensee, except to the extent, at the time of such termination,
               such information is no longer Confidential Information (other
               than due to a breach of Article 18 by Licensor); and

          (iii) Licensee shall have a fully paid up, irrevocable, exclusive
               license under the Licensed Technology, with the right to
               sublicense, to make, have made, develop, use, distribute, offer
               for sale, sell, import and export the Product in the Territory;
               and

          (iv) If at the time of such termination Licensor has not yet
               transferred the Manufacturing Know-How to Licensee and the
               Third-Party Manufacturer(s) as provided in Article 4, it shall do
               so promptly in accordance with the provisions of Article 4.

          (c) Upon termination of Licensee's rights under the license granted in
this Agreement in a particular Disease Area in a particular country due to
failure of Due Diligence by Licensee as set forth in Section 6.4(a) or 6.4(c):

          (i)  All rights and license granted to Licensee hereunder with respect
               to such particular Disease Area in such country, including the
               license to develop, use, manufacture and sell the Compound, Bulk
               and Product in such particular Disease Area in such country,
               shall immediately terminate and shall revert to Licensor;

          (ii) Licensee shall cease all use of the Licensed Know-How and any
               other Confidential Information disclosed by Licensor with respect
               to such particular Disease Area in such country, except to the
               extent, at the time of such termination, the Licensed Know-How
               and any other Confidential Information disclosed by Licensor is
               no longer Confidential Information (other than due to a breach of
               Article 18 by Licensee);

<PAGE>

          (iii) Licensee shall transfer to Meiji or NPC, as Licensor directs
               [ * ], any Regulatory Approvals (including IND's) and
               applications for Regulatory Approvals (including IND's) for the
               Product in such particular Disease Area in such country, together
               with the related Licensee Information and the full dossier and
               all data submitted in support of such Regulatory Approvals
               (including IND's), excluding any Regulatory Approvals pertaining
               to the Device, applications therefor, and data and information
               related thereto; and

          (iv) Licensee's rights under this Agreement in all Disease Areas and
               in all countries not the subject of termination under Section
               6.4(a) or 6.4(c) shall remain unaffected and in full force.

     16.7 Survival of Liability and Other Obligations. Expiration or termination
of this Agreement through any means and for any reason shall not affect any
accrued obligations, rights and remedies prior thereto and shall be without
prejudice to the rights and remedies of either party with respect to any
antecedent breach of any provision of this Agreement, which rights and remedies
shall be subject to the terms and conditions of this Agreement. The rights and
obligations described in the following Articles of this Agreement shall survive
its expiration or termination: Articles 7, 12, 16, 18, 19 and 20 plus such other
provisions of the Agreement which by their express terms or their context are
intended to survive expiration or termination of this Agreement.

ARTICLE 17. FORCE MAJEURE

     None of the parties shall be held liable or responsible to the other
parties nor be deemed to have defaulted under or breached this Agreement for
failure or delay in fulfilling or performing any obligations under this
Agreement when such failure or delay is caused by or results from causes beyond
the reasonable control of the affected party, including but not limited to fire,
floods, embargoes, wars, acts of war (whether war is declared or not),
insurrections, riots, civil commotions, strikes, lockouts or other labor
disturbances, acts of God or acts, omissions or delays in acting by any
governmental authority or the other parties; provided, however, that the party
so affected shall use reasonable efforts to avoid or remove such causes of delay
or nonperformance, and shall continue to perform hereunder with reasonable
dispatch

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whenever such causes are removed. Any party shall provide the other parties with
prompt written notice of any delay or failure to perform that occurs by reason
of force majeure.

ARTICLE 18. CONFIDENTIALITY AND DISCLOSURE

     18.1 Confidentiality. Each party shall maintain in confidence, and neither
party shall disclose to any third party, any Confidential Information received
by it from the other party pursuant to this Agreement, or pursuant to the
Confidential Disclosure Agreement described in Section 18.3, nor use any such
Confidential Information for any purpose other than the purpose of this
Agreement without the prior written consent of the other party. Neither party
shall use, disclose, transfer or grant use of such Confidential Information
except as expressly authorized by this Agreement or as reasonably necessary to
perform acts permitted by this Agreement. This obligation shall continue for a
period of [ * ] years after expiration or termination of this Agreement.

     18.2 Disclosure. Nothing contained in this Article shall be construed to
restrict the parties from disclosing or using Confidential Information as
reasonably necessary: (i) in prosecuting or defending litigation; (ii) in
responding to court order or other government order or request; or (iii) to
perform acts permitted by this Agreement, including developing the Product,
seeking and maintaining Regulatory Approval of the Product, marketing, sale or
use of the Product, and filing and prosecuting patent applications; provided
that, if any party is required or finds it reasonably necessary to make any such
disclosure of Confidential Information, it will to the extent practicable and
appropriate use reasonable efforts to secure confidential treatment of such
disclosed information.

     18.3 Prior Confidentiality Agreement. Information disclosed under the
Confidential Disclosure Agreement (the "CDA") between Meiji and Licensee dated
July 28, 1999, information and data generated by or on behalf of Licensee under
the Statement of Investigator dated September 10, 1999, and information
disclosed under the CDA between NPC and Licensee dated January 20, 2000, shall
be covered by the terms of this Article 18.

ARTICLE 19. REPRESENTATIONS AND WARRANTIES

     19.1 By Licensor. Licensor represents and warrants that:

          (a) Licensor has the right, power and authority to grant to Licensee

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the exclusive licenses and rights to the Licensed Technology in the Territory
set forth in this Agreement and to enter into this Agreement and perform
Licensor's obligations hereunder;

          (b) This Agreement has been duly executed and delivered by Licensor
and is a legal, valid and binding obligation enforceable against Licensor in
accordance with its terms, subject to applicable bankruptcy, insolvency,
reorganization, arrangement, moratorium and other laws relating to or affecting
creditors' rights generally and equitable principles;

          (c) The execution, delivery and performance of this Agreement, and the
rights and licenses granted hereunder, do not conflict with, violate or breach
any agreement to which Licensor is a party, and there are no agreements,
assignments or encumbrances in existence inconsistent with the provisions of
this Agreement. Licensor has not granted and will not grant any license or other
right in any of the Licensed Technology that interferes with or conflicts with
any of the licenses or rights granted to Licensee under this Agreement;

          (d) The License Agreement dated as of [ * ] between NPC and Meiji
relating to NPe6 (the "NPC-Meiji Agreement") remains in effect, without breach
by either party. This Agreement is not a sublicense of the NPC-Meiji Agreement.
[ * ]. Meiji has granted no sublicense or other rights under the NPC-Meiji
Agreement in the Territory;

          (e) As of the Effective Date of this Agreement, Licensor is the sole
and exclusive owner of, or controls the sole and exclusive rights to, the
Licensed Technology including the Compound (including, without limitation, all
versions of the Drug Master File filed by Meiji);

          (f) To the best knowledge of Licensor as of the Effective Date, no
third party has any right, title or interest in or to the Licensed Technology in
the Territory; [ * ].

          (g) As of the Effective Date, Licensor has not received any notice
from any third party claiming any ownership interest or control in the Licensed
Technology, including the Compound;

          (h) The Licensed Technology has not knowingly been obtained through
any activity, omission or representation that would limit or destroy the

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validity or enforceability of the Licensed Technology, and Licensor has, as of
the Effective Date, no knowledge or information that would have a material
adverse impact on the validity and/or enforceability of the Licensed Technology;

          (i) As of the Effective Date, there are no actions pending, or, to the
best of Licensor's knowledge as of the Effective Date, threatened before any
court or tribunal relating to the Licensed Technology, and no Licensed Patent
has been involved in any reissue, reexamination, interference, opposition or
equivalent or similar proceeding or in any litigation, [ * ];

          (j) To the best knowledge of Licensor as of the Effective Date, the
issued Licensed Patents are valid and enforceable and are not being infringed by
any third party in the Territory or Japan. Licensor has, as of the Effective
Date, no knowledge or information that would materially affect the validity
and/or enforceability of the Licensed Patents. However, Licensor does not
represent and warrant that any of the Licensed Patents is valid and enforceable;

          (k) As of the Effective Date, Licensor has not received any notice
from any third party claiming that the development, manufacture, use,
importation, exportation or sale of NPe6 or ME2906 will infringe any patent of
any third party;

          (l) No other license for currently existing patents or patent
applications of Licensor or Affiliates of Licensor is required to develop, make,
have made, use, import, export, offer for sale or sell the Compound in the
Territory;

          (m) Licensor has not knowingly misstated any material fact with
respect to the Compound, including its manufacture, safety and efficacy, or the
Licensed Patents or with respect to the information related thereto provided by
Licensor to Licensee, nor has Licensor knowingly omitted to state any material
fact or provide any material information required to make such information not
misleading;

          (n) As of the Effective Date, Licensor neither owns nor controls any
compound, other than the Compound, for use with PDT, or any intellectual
property rights related to any such compound, and is not, as of the Effective
Date, developing or negotiating to obtain any such compound or intellectual
property rights; and

          (o) The execution and delivery by Licensor of this Agreement require
no governmental approvals to be obtained on the part of Licensor, or, if
required, Licensor has obtained such approvals.

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          (p) Without limiting Licensor's obligations regarding the Licensed
Know-How under Section 2.1, Article 3, Article 4, Section 6.6, Article 7 and
Article 15 of this Agreement, and except for and subject to Licensor's
representations and warranties set forth above, LICENSOR MAKES NO OTHER WARRANTY
WITH RESPECT TO THE ACCURACY, COMPLETENESS, APPLICABILITY, FITNESS OR
MERCHANTABILITY OF THE LICENSED KNOW-HOW, INCLUDING THE ENGLISH TRANSLATION
THEREOF.

     19.2 By Licensee. Licensee represents and warrants that:

          (a) Licensee has the right, power and authority to enter into this
Agreement and to perform Licensee's obligations hereunder.

          (b) This Agreement has been duly executed and delivered by Licensee
and is a legal, valid and binding obligation enforceable against Licensee in
accordance with its terms, subject to applicable bankruptcy, insolvency,
reorganization, arrangement, moratorium and other laws relating to or affecting
creditors' rights generally and equitable principles;

          (c) The execution, delivery and performance of this Agreement, and the
rights and licenses granted hereunder, do not conflict with, violate or breach
any agreement to which Licensee is a party, and there are no agreements,
assignments or encumbrances in existence inconsistent with the provisions of
this Agreement;

          (d) The execution and delivery by Licensee of this Agreement require
no governmental approvals to be obtained on the part of Licensee, or, if
required, Licensee has obtained such approvals.

ARTICLE 20. MISCELLANEOUS

     20.1 Assignment. Neither party may assign any right or obligation hereunder
without the prior written consent of the other party, except if such assignment
arises under a transaction in which the assigning party is selling or
transferring substantially all of its business or is being acquired by or
merging with a third party (which assignment shall be permitted without the
consent of the other party but shall require prompt written notice to the other
party). This Agreement shall be binding upon and inure to the benefit of the
parties' respective successors and permitted assigns. Any attempted assignment
in violation of this provision shall be void and of no effect. Licensor
acknowledges that Licensee plans to convert from a limited partnership form to a
corporate form, that Licensee then plans to merge with and assign its rights,
interests and obligations in this Agreement to such corporation, and that this
shall be a permitted assignment under this Agreement.
<PAGE>

     20.2 Severability. Each party intends not to violate any public policy,
statutory or common law, rule, regulation, treaty or decision of any government
agency or executive body thereof of any country or community or association of
countries. If any term or provision of this Agreement is held to be invalid,
illegal or unenforceable by a court or other governmental authority of competent
jurisdiction, such invalidity, illegality or unenforceability shall not affect
any other term or provision of this Agreement, which shall remain in full force
and effect. To the extent possible, the parties shall revise such invalid,
illegal or unenforceable term or provision in a manner that will render such
term or provision valid without impairing the parties' original intent. The
holding of a term or provision to be invalid, illegal or unenforceable in one
jurisdiction shall not have any effect on the enforceability of the term or
provision in any other jurisdiction.

     20.3 Notices. Any consent, notice or approval required or permitted to be
given or made under this Agreement by one of the parties hereto to the other
shall be in writing, delivered personally or by facsimile (and promptly
confirmed by personal delivery, first-class mail or commercial courier),
first-class mail or commercial courier (e.g., Fed Ex, DHL), postage prepaid
(where applicable), addressed to such other party at its address indicated
below, or to such other address as the addressee shall have last furnished in
writing to the addressor, and shall be effective upon the earlier of its
documented receipt by the addressee or [ * ] business days after dispatch of
such notice in accordance with this Section.

If to NPC:      Nippon Petrochemicals Co., Ltd.
                3-1, Uchisaiwai-cho 1-chome
                Chiyoda-ku, Tokyo 100-8530
                Japan
                Attention: Director, General Manager of
                New Business Development Department

If to Meiji:    Meiji Seika Kaisha, Ltd.
                4-16, Kyobashi 2-Chome
                Chuo-ku, Tokyo 104-8002
                Japan
                Attention: President, Pharmaceuticals

If to Licensor: To Meiji (at the above-specified address) on behalf of NPC and
                Meiji

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If to Licensee: Light Sciences Limited Partnership
                1065-12th Avenue NW, Suite E-5
                Issaquah, Washington 98027
                U.S.A.
                Attention: Both the President and the V.P., Product Development

     20.4 Applicable Law. This Agreement is deemed to have been entered into in
the State of New York, United States of America, and it shall be governed by,
construed, and enforced in accordance with the laws of the State of New York,
United States of America, excluding its conflict-of-laws provision.

     20.5 Entire Agreement. This Agreement, including the exhibits hereto,
contains the entire understanding of the parties with respect to the subject
matter hereof. All express or implied agreements and understandings, either oral
or written, heretofore made are expressly merged in and made a part of this
Agreement. There are no understandings, obligations, indemnifications,
warranties and representations except as expressly set forth herein, and no
rights or licenses are granted except as expressly set forth herein. This
Agreement may be amended, or any term hereof modified, only by a written
instrument duly executed by all the parties hereto.

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

     20.7 Independent Contractors. It is expressly understood and agreed that
Licensor and Licensee are and shall be independent contractors and that the
relationship between the parties shall not constitute a partnership, joint
venture or agency. None of the parties hereto shall have the authority to make
any statements, representations or commitments of any kind, or to take any
action, which shall be binding on the other parties, without the prior written
consent of the parties to do so, except as expressly provided in this Agreement.

     20.8 Waiver. The waiver by either party hereto of any right hereunder or of
a failure to perform or breach by the other party shall not be deemed a waiver
of any other right hereunder or of any other failure or breach, whether of a
similar nature or otherwise.

     20.9 Dispute Resolution. In the event a dispute arises between the parties
relating to this Agreement, or any alleged breach of this Agreement or the
grounds for the termination thereof (the "Dispute"), the aggrieved party shall
notify the other party in writing of such Dispute, and the parties shall attempt
to resolve such Dispute

<PAGE>

in good faith. If, within [ * ] days of such written notice, the parties have
not succeeded in resolving the Dispute, the matter shall be referred by the
aggrieved party for review and resolution by the CEOs of Licensor and Licensee.
The CEOs shall attempt in good faith to resolve the Dispute for a period of
[ * ] days and shall, if they mutually agree, submit the dispute to voluntary
mediation at such place and following such procedures as the parties shall
reasonably agree. If no successful resolution of the Dispute has been mutually
agreed to at the end of this period, either party shall be free to seek legal or
equitable relief under Section 20.10 of this Agreement.

     20.10 Arbitration. Licensor and Licensee agree that any Dispute that arises
between them in connection with this Agreement, which cannot be amicably
resolved by the parties pursuant to Section 20.9, shall be finally resolved by
binding arbitration to be conducted by a single arbitrator or a panel of three
(3) arbitrators. If arbitration is initiated by Meiji and/or NPC against
Licensee, the arbitration shall be conducted in Seattle, Washington, U.S., in
the English language pursuant to the Rules of the American Arbitration
Association. If arbitration is initiated by Licensee against Meiji and/or NPC,
arbitration shall be conducted in Tokyo, Japan, in the Japanese language,
pursuant to the Rules of the Japan Commercial Arbitration Association. Such
arbitrator(s) shall be lawyers or business executives or experts in the
pharmaceutical business, having no business relationship with any of the
parties, who are experienced in the subject matter that is the basis of the
dispute. The parties shall mutually agree on such arbitrator(s) within [ * ]
days after one party's receipt of notice initiating the arbitration proceeding
from the other party. If the parties do not mutually agree on such arbitrator(s)
within such period, the arbitration shall be conducted by a panel of three (3)
arbitrators, one to be selected by Licensor and one to be selected by Licensee
within [ * ] days after the end of the initial [ * ] period. Those two
arbitrators shall then mutually agree on the third arbitrator within [ * ] days
thereafter. If they do not reach such agreement, the Director of the Arbitration
Association office in the city where the arbitration will be conducted shall
select such third arbitrator, as well as any other arbitrator(s) the parties
were entitled to select but did not select within the allotted time period. The
arbitration award at the conclusion of the proceeding, which shall be the final
decision of the majority of the arbitrators, may include legal and equitable
relief and shall be final and binding upon both parties. Judgment upon the award
rendered through arbitration may be entered in any court having jurisdiction, or
application may be made to such court for a judicial acceptance of the award, an
order of enforcement or such other appropriate remedy as may be available.

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     20.11 Public Announcements. Except as may otherwise be required by law or
regulation (including as may be required by the Securities and Exchange
Commission or by the disclosure policies of a major Stock Exchange), neither
party shall make any public announcement concerning this Agreement or the
subject matter hereof without the prior written consent of the other party. If
any party determines that notification is required by law or regulation, such
party shall submit a copy of the proposed announcement to the other party for
review. The other party shall have [ * ] business days to review such
announcement and provide its comments and suggestions. The party issuing such
announcement, subject to legal requirements, shall use its every effort to
accommodate the other party's comments and suggestions.

     20.12 Limitations of Liability. Without limiting the parties'
indemnification obligations for third-party Claims under Article 12 or their
obligations under Section 14.4, IN NO EVENT SHALL EITHER PARTY OR ITS
AFFILIATES, OR THEIR RESPECTIVE DIRECTORS, OFFICERS, EMPLOYEES, AGENTS OR
REPRESENTATIVES BE LIABLE TO THE OTHER PARTY FOR ANY INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES, WHETHER BASED UPON A CLAIM OR
ACTION OF CONTRACT, WARRANTY, NEGLIGENCE, STRICT LIABILITY OR OTHER TORT OR
LEGAL THEORY, OR ARISING OUT OF THIS AGREEMENT.

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

     20.14 Official Language. The official text of this Agreement and any
appendices, exhibits and schedules hereto, or any notice or consent given or
reports, accounts or statements required by this Agreement, shall be in English.
In the event of any dispute concerning the construction or meaning of this
Agreement, reference shall be made only to this Agreement as written in English
and not to any other translation into any other language.

     20.15 Further Documents. Each party hereto agrees to execute such further
documents and take such further steps as the other party reasonably determines
may be necessary or desirable to effectuate the purposes of this Agreement.

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

NIPPON PETROCHEMICALS CO., LTD.         MEIJI SEIKA KAISHA, LTD.


By: /s/ Kenzo Saikawa                   By: /s/ Yutaka Ogawa
    ---------------------------------       ------------------------------------
    Kenzo Saikawa                           Yutaka Ogawa
    President                               President, Pharmaceuticals


LIGHT SCIENCES LIMITED PARTNERSHIP


By: /s/ Steven Russell
    ---------------------------------
    Steven Russell
    President, Light Sciences II Co.,
    General Partner

<PAGE>

                                    EXHIBIT A

                                LICENSED PATENTS

                                      [ * ]

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<PAGE>

                                    EXHIBIT B

                                DEVELOPMENT PLAN

                                      [ * ]

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                                    EXHIBIT C

                                 TRANSFER OF IND

                                      [ * ]

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<PAGE>

                                    EXHIBIT D

                       LIST OF DOCUMENTS TO BE TRANSLATED

                                      [ * ]

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