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                                                                    Exhibit 10.9

                      "CONFIDENTIAL TREATMENT REQUESTED BY        EXECUTION COPY
                               ACTIVBIOTICS, INC."

                                LICENSE AGREEMENT

                                     BETWEEN

                                   PFIZER INC

                                       AND

                         METAPHORE PHARMACEUTICALS, INC.

                                DECEMBER 19, 2003

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

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                                                                  EXECUTION COPY

                                TABLE OF CONTENTS

ARTICLE 1: DEFINITIONS                                                         1
   1.1    "Affiliates"                                                         1
   1.2    "Confidential Information"                                           2
   1.3    "Control" or "Controlled"                                            2
   1.4    "Know-How"                                                           2
   1.5    "Licensed Intellectual Property"                                     2
   1.6    "Licensed Product"                                                   2
   1.7    "Net Sales"                                                          3
   1.8    "Oral Product"                                                       3
   1.9    "Patent(s)"                                                          4
   1.10   "Patent Rights"                                                      4
   1.11   "Person"                                                             4
   1.12   "Sublicensee"                                                        4
   1.13   "Term"                                                               4
   1.14   "Territory"                                                          4
   1.15   "Third Party"                                                        4
   1.16   "Valid Claim"                                                        4

ARTICLE 2: LICENSE GRANT; RETAINED RIGHTS; PFIZER OPTION                       5
   2.1    License to Metaphore                                                 5
   2.2    Pfizer Retained Rights                                               5
   2.3    Pfizer Option                                                        5
   2.4    Access to Know-How                                                   7
   2.5    Pfizer Direct Sublicensee Licenses                                   7

ARTICLE 3: ROYALTIES; PAYMENT TERMS                                            8
   3.1    Royalties                                                            8
   3.2    Timing of Payments                                                   9
   3.3    Length of Royalty Obligations; Reduction in Royalties                9
   3.4    Payment Reports                                                      9
   3.5    Record Keeping; Audits                                              10
   3.6    Currency and Method of Payments                                     10
   3.7    Interest; Late Payments                                             11
   3.8    Exchange Control                                                    11
   3.9    Withholding Taxes                                                   11

ARTICLE 4: INTELLECTUAL PROPERTY RIGHTS                                       12
   4.1    Prosecution, Maintenance and Protection of Intellectual Property
             Rights                                                           12
   4.2    Third Party Infringement                                            13
   4.3    Third Party Claims                                                  14
   4.4    Certain Deductions                                                  16

ARTICLE 5: TERM; DEFAULT; AND TERMINATION                                     16

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED


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   5.1    Term                                                                16
   5.2    Default                                                             16
   5.3    Termination by Metaphore                                            17
   5.4    Effect of Expiration and Termination                                17
   5.5    Survival                                                            18
   5.6    No Damages on Termination                                           18

ARTICLE 6: REPRESENTATIONS AND WARRANTIES                                     18
   6.1    Party Representations, Warranties and Certain Covenants             18
   6.2    Pfizer Representations, Warranties and Certain Covenants            19
   6.3    DISCLAIMER                                                          20
   6.4    LIMITATION ON DAMAGES                                               20

ARTICLE 7: INDEMNIFICATION                                                    20
   7.1    Indemnification by Metaphore                                        20
   7.2    Indemnification by Pfizer                                           20
   7.3    Procedures                                                          21

ARTICLE 8: CONFIDENTIALITY                                                    21
   8.1    Confidential Information                                            21
   8.2    Exceptions                                                          22
   8.3    Certain Obligations                                                 23
   8.4    Press Releases, Disclosures and Public Announcements                24
   8.5    Return; and Permitted Uses                                          24
   8.6    Termination                                                         24

ARTICLE 9: MISCELLANEOUS                                                      25
   9.1    Assignment and Delegation                                           25
   9.2    Termination of Collaborative Research Agreement                     25
   9.3    Entire Agreement; Compliance                                        25
   9.4    Amendments                                                          25
   9.5    Governing Law                                                       25
   9.6    Force Majeure                                                       25
   9.7    Severability                                                        26
   9.8    Notice                                                              26
   9.9    Independent Contractor                                              27
   9.10   Waiver                                                              27
   9.11   Interpretation                                                      27
   9.12   No Third Party Beneficiaries                                        28
   9.13   License Survival During Bankruptcy                                  28
   9.14   Counterparts                                                        28

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED


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                                LICENSE AGREEMENT

     This LICENSE AGREEMENT ("Agreement") is made and entered into as of the
19th day of December, 2003 (the "Effective Date") by and between METAPHORE
PHARMACEUTICALS, INC., a Delaware corporation with offices at One Bridge Plaza,
Suite 500, Fort Lee, New Jersey 07024 (Metaphore Pharmaceuticals, Inc., together
with its Affiliates, "Metaphore") and PFIZER INC, a Delaware corporation, with
offices at 235 East 42nd Street, New York, New York 10017 (Pfizer Inc, together
with its Affiliates, "Pfizer"). Metaphore and Pfizer are each referred to herein
individually, as a "Party" and collectively, as the "Parties."

                                   WITNESSETH:

     WHEREAS Metaphore and Pfizer (as the successor to Pharmacia Corporation
which was the successor to the Monsanto Company) are parties to that certain
Collaborative Research and Development License Agreement dated December 23, 1998
as amended by the First Amendment to the Collaborative Research and Development
License Agreement dated July 8, 1999 and the Addendum to the Collaborative
Research and Development License Agreement dated January 12, 2000, collectively
the "Collaborative Research Agreement"; and

     WHEREAS Metaphore and Pfizer desire to terminate the Collaborative Research
Agreement in its entirety and to enter into this Agreement under which Pfizer
will grant an exclusive license to Metaphore, all on the terms and conditions
set forth herein.

     NOW, THEREFORE, in consideration of the mutual covenants herein contained,
and for other good and valuable consideration, the amount and sufficiency of
which are hereby acknowledged, the Parties hereby agree as follows:

                             ARTICLE 1: DEFINITIONS

     1.1 "Affiliates" means any Person that directly or indirectly controls, is
controlled by, or is under common control with a Party. For purposes of this
Section 1.1, "control" shall mean (a) in the case of corporate Persons, direct
or indirect ownership of more than fifty percent (50%) of the stock or shares
having the right to vote for the election of directors, and (b) in the case of
non-

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

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corporate Persons, direct or indirect ownership of more than fifty percent (50%)
of the equity interest with the power to direct the management and policies of
such non-corporate Persons.

     1.2 "Confidential Information" shall have the meaning set forth in Article
8.

     1.3 "Control" or "Controlled" in the context of intellectual property
rights, means rights to intellectual property sufficient to grant the applicable
license or sublicense under this Agreement, provided that where a license or
sublicense under this Agreement shall be exclusive, if Pfizer does not have the
right under a Third Party agreement entered into prior to the Effective Date
(which Pfizer shall have disclosed on Exhibit A if any such agreements exist) to
grant an exclusive license or sublicense, such license or sublicense shall be
non-exclusive.

     1.4 "Know-How" means all techniques, data, trade secrets, materials and
other know-how and information and including all inventions (whether or not
patentable or reduced to practice), disclosures, improvements, developments,
discoveries, practices, methods, processes, concepts, copyrights, biological
materials, documents, computer data, computer code, clinical and regulatory
strategies or data, test data, analytical and quality control data, formulation,
manufacturing, patent data or descriptions and files, drawings, specifications,
designs, plans, proposals and technical data and manuals, laboratory notes,
software, tests, protocols, business plans, marketing research and materials,
and all other intellectual property and other rights owned or Controlled by
Pfizer that were obtained or developed under the Collaborative Research
Agreement or that were obtained by Metaphore, or provided to Metaphore by or on
behalf of Pfizer, Pharmacia Corporation and/or the Monsanto Company (and
including all intellectual property and other rights provided to, or obtained or
developed by or on behalf of, Metaphore under the Collaborative Research
Agreement that are owned or Controlled by Pfizer).

     1.5 "Licensed Intellectual Property" means all of the Patent Rights and
Know-How covered by the license granted to Metaphore and its Affiliates pursuant
to Section 2.1 in the Territory.

     1.6 "Licensed Product" means any composition or medical device the
manufacture, use, sale, import or offer for sale of which would, in the absence
of a license, infringe a Valid Claim of any Patent Right, and/or infringe or
otherwise violate any other Licensed Intellectual Property.

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

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     1.7 "Net Sales" means the gross invoiced sales in the Territory of Licensed
Products (in the final form intended for use by the end user) by Metaphore
and/or its Affiliates and/or any Sublicensees to Third Parties less any of the
following, determined under GAAP for sales of Licensed Products in the
Territory, to the extent taken or allowed:

          (a) credits, allowances and rebates to, and chargebacks from the
account of, customers for rejected, damaged, out-dated, withdrawn, recalled or
returned Licensed Product or on account of any retroactive price reductions;

          (b) trade, cash and quantity discounts, rebates (including Medicaid
rebates or other similar government rebate, discount or chargeback programs) and
other price reduction programs;

          (c) sales, value-added, inventory and other direct taxes;

          (d) customs duties, surcharges and other governmental charges incurred
in connection with the exportation or importation of the Licensed Product;

          (e) transport, freight, insurance, handling and distribution
transportation charges and insurance through the whole distribution pipeline;
and

          (f) receivables which are reserved as uncollectable.

Sales between or among Metaphore and/or its Affiliates and/or any Sublicensees
shall be excluded from the computation of Net Sales, but Net Sales shall
otherwise include the first sales to Third Parties by Metaphore or any such
Affiliates or any such Sublicensees, as applicable. The supply of Licensed
Products as free commercial samples or for clinical use shall not be included
within the computation of Net Sales.

     1.8 "Oral Product" means any oral product which is a composition, the
active ingredient of which [***] [***] [***].

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

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     1.9 "Patent(s)" means patents and patent applications and all additions,
divisions, continuations, continuations-in-part, pipeline protection,
substitutions, reissues, reexaminations, extensions, registrations, patent term
extensions, SUPPLEMENTARY PROTECTION CERTIFICATES, COUNTERPARTS and renewals of
any of the foregoing.

     1.10 "Patent Rights" means those patents and patent applications set forth
in Exhibit A attached hereto, and any additions, divisions, continuations,
continuations-in-part, pipeline protection, substitutions, reissues,
reexaminations, extensions, registrations, patent term extensions, supplementary
protection certificates, renewals and counterparts of any of the patents or
patent applications set forth in Exhibit A or of any of the foregoing.

     1.11 "Person" means any person or entity, including any individual,
trustee, corporation, partnership, trust, unincorporated organization, limited
liability company, business association, firm, joint venture or governmental
agency or authority.

     1.12 "Sublicensee" means any Third Party that has been granted a sublicense
by Metaphore or any of its Affiliates under the Licensed Intellectual Property.
For the avoidance of doubt, upon the expiration or termination of any such
sublicense to a Third Party, such Third Party shall automatically and
immediately be excluded from this definition and shall no longer be a
"Sublicensee" hereunder.

     1.13 "Term" shall have the meaning set forth in Section 5.1.

     1.14 "Territory" means all the countries of the world.

     1.15 "Third Party" means a Person that is not Metaphore or Pfizer.

     1.16 "Valid Claim" means (i) any claim of an issued and unexpired Patent
included within the Patent Rights which has not been held permanently revoked,
unenforceable or invalid by a decision of a court or other governmental agency
of competent jurisdiction, unappealable or unappealed within the time allowed
for appeal, and which has not been admitted to be invalid or unenforceable
through reissue or disclaimer or otherwise; and (ii) a claim of a pending Patent

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

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application included within the Patent Rights which claim was filed in good
faith and has not been abandoned or finally disallowed without the possibility
of appeal or refiling of such application.

            ARTICLE 2: LICENSE GRANT; RETAINED RIGHTS; PFIZER OPTION

     2.1 License to Metaphore. Pfizer hereby grants to Metaphore, and Metaphore
hereby accepts, an exclusive right and license (including the right to grant
sublicenses which may in turn include the right to grant further sublicenses)
under the Know-How and Patent Rights to utilize the Know-How and Patent Rights
and to make, have made, use, sell, offer for sale and import Licensed Products
in the Territory. The term "exclusive" as used herein shall operate to exclude
Pfizer, except as set forth in Section 2.2.

     2.2 Pfizer Retained Rights. Pfizer shall retain the non-exclusive,
non-transferable right under the Licensed Intellectual Property in the Territory
solely to conduct research activities. Except as provided in the foregoing
sentence, during the Term of this Agreement, neither Pfizer nor its Affiliates
shall research, develop, manufacture or commercialize any Licensed Products in
the Territory, and shall not license, assist or enable any Third Party to do any
of the foregoing, except for the research activities expressly permitted above
in this Section 2.2 or pursuant to an agreement entered into by the Parties
pursuant to Section 2.3. For the avoidance of doubt, Pfizer acknowledges and
agrees that in the event that Pfizer wishes to make, have made, use, sell, offer
for sale or import any products or to otherwise operate under, or to utilize any
of the Licensed Intellectual Property other than for research purposes as
permitted in this Section 2.2, Pfizer would have to obtain a written license
from Metaphore, if and as may be agreed to by Metaphore.

     2.3 Pfizer Option.

          2.3.1 For a period beginning on the Effective Date and ending three
(3) years thereafter (the "Option Period"), Pfizer shall have an option to
negotiate an agreement with Metaphore for the right to develop and commercialize
certain Oral Product(s) that Metaphore offers to Pfizer in a Notice (as defined
below) during the Option Period, as provided below in this Section. During the
Option Period, if Metaphore decides to seek a partner, or discuss with any Third
Parties an agreement, for the development and commercialization of any Oral
Product(s), Metaphore shall notify Pfizer of such Oral Product(s) (a "Notice").
Metaphore shall send any such Notice to the

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

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attention of the Vice President, Strategic Alliances, Pfizer Global Research and
Development (or such other Person as Pfizer may designate to Metaphore in
writing). Together with any such Notice, Metaphore shall provide Pfizer with
data relating to such Oral Product(s) identified in such Notice that Metaphore
may have in its possession or control with the right to disclose to Pfizer as
Metaphore determines is relevant and necessary to allow Pfizer to review such
Oral Product(s) at the applicable stage of development. Such data would be
provided to Pfizer solely for the limited purpose of determining whether it
wishes to enter into a development and commercialization agreement with
Metaphore with respect to such Oral Product(s) and not for any other purpose,
and would be considered Metaphore Confidential Information. If Pfizer is
interested in developing and commercializing such Oral Product(s), it shall so
notify Metaphore in writing within forty-five (45) days of Pfizer's receipt of
such Notice from Metaphore. If Pfizer notifies Metaphore within forty-five (45)
days of its receipt of such Notice that it is interested in negotiating an
agreement with Metaphore for the right to develop and commercialize the Oral
Product(s) set forth in the Notice, then the Parties shall discuss and negotiate
in good faith a term sheet setting out the terms and conditions of a development
and commercialization agreement for such Oral Product(s) in the Territory within
sixty (60) days of Pfizer's notification to Metaphore of its interest in
negotiating an agreement. If the Parties mutually agree upon a term sheet within
such sixty (60) day time period, then the Parties shall discuss and negotiate in
good faith the terms and conditions of a definitive agreement mutually agreed
upon by the Parties, and based on the mutually agreed term sheet. In the event
that (a) Pfizer does not notify Metaphore within forty-five (45) days of
Pfizer's receipt of such Notice from Metaphore that it is interested in
negotiating an agreement with Metaphore for rights to such Oral Product(s) set
forth in the Notice, or (b) the Parties do not agree in writing upon a term
sheet within sixty (60) days of Pfizer's notification to Metaphore of its
interest in negotiating an agreement, or (c) the Parties do not execute a
definitive agreement within sixty (60) days of the Parties having agreed upon a
term sheet during the applicable sixty (60) day period that the Parties had to
negotiate such term sheet under this Section, then Metaphore shall have no
further obligation to Pfizer with respect to such Oral Product(s) and, for the
avoidance of doubt may develop and/or commercialize such Oral Product(s) itself
or with any other Person.

          2.3.2 If, at the end of the Option Period, Metaphore has not provided
a Notice (as defined in Section 2.3.1) to Pfizer during the Option Period, then
Metaphore shall notify Pfizer that

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES PROMULGATED UNDER THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

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Metaphore will give a presentation to Pfizer concerning certain Oral Product(s)
identified by Metaphore for the presentation. Such presentation would be similar
to what Metaphore would give as a business development presentation to a Third
Party to determine whether such Third Party is interested in discussing a
potential business transaction with Metaphore, and Metaphore shall not have any
obligation to disclose any confidential information unless Metaphore decides in
its DISCRETION TO DO SO (AND THEN ANY SUCH CONFIDENTIAL INFORMATION DISCLOSED
SHALL BE CONSIDERED TO BE Confidential Information of Metaphore). Pfizer shall
notify Metaphore within thirty (30) days of its receipt of such notice from
Metaphore whether it would like to see the presentation. If Pfizer notifies
Metaphore that it is not interested in seeing the presentation or does not send
notice to Metaphore within such thirty (30) day period, Metaphore shall not have
any obligation to give any such presentation to Pfizer.

     2.4 Access to Know-How. Pfizer shall use its reasonable commercial efforts
to cooperate with Metaphore and to locate and provide copies of, and to
otherwise convey, any Know-How to Metaphore that is in Pfizer's possession or
control that Metaphore may request for use in connection with any regulatory
activities, filings or submissions and/or in connection with any matters
relating to the filing, prosecution or enforcement of any of the Licensed
Intellectual Property, but only if and as may be reasonably requested by
Metaphore from time to time.

     2.5 Pfizer Direct Sublicensee Licenses. Pfizer hereby agrees to enter into
direct license agreements with any sublicensees that have been granted a
sublicense under the Licensed Intellectual Property with respect to any Oral
Products, as may be requested by Metaphore either at the time of entering into
any agreement with any such sublicensee or thereafter. Any such direct license
agreement by Pfizer to a sublicensee shall (i) grant a license under the
Know-How and Patent Rights from Pfizer to such sublicensee with respect to such
Oral Product(s); (ii) be a present grant that would be effective with respect to
each such Oral Product upon the occurrence of a partial termination by Pfizer
pursuant to Section 5.2.1, if any, of the license granted to Metaphore pursuant
to Section 2.1 due to a material breach by Metaphore of any of its obligations
under Section 2.3 with respect to such Oral Product; and (iii) be consistent
with the terms and conditions of this Agreement and the sublicense granted to
such sublicensee. For the avoidance of doubt, in the event that Pfizer enters
into a direct license agreement as set forth herein with a sublicensee and there
is a partial

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED
WITH THE SECURITIES PROMULGATED UNDER THE SECURITIES EXCHANGE ACT OF 1934, AS
AMENDED

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termination by Pfizer pursuant to Section 5.2.1 of the license granted to
Metaphore pursuant to Section 2.1 due to a material breach by Metaphore of any
of its obligations under Section 2.3 with respect to such Oral Product,
Metaphore shall not owe or otherwise be liable for the payment of any royalty
payments to Pfizer arising from the sales of such Oral Product, and such
sublicensee shall no longer be deemed to be a sublicensee hereunder with respect
to such Oral Product.

                       ARTICLE 3: ROYALTIES; PAYMENT TERMS

     3.1 Royalties. Subject to and in accordance with the terms and conditions
of this Agreement, during the Term of this Agreement, in consideration for the
rights granted to Metaphore and its Affiliates by Pfizer hereunder, in each
country of the Territory in which Pfizer owns or Controls any Licensed
Intellectual Property that would, but for the license granted by Pfizer to
Metaphore pursuant to Section 2.1, be infringed by the manufacture, use, sale,
import or offer for sale of a Licensed Product, Metaphore shall pay to Pfizer,
on a Licensed Product-by-Licensed Product basis, in accordance with the timing
set forth in Section 3.2 and subject to the terms and conditions set forth in
Section 3.3, the following applicable royalty based on the Net Sales by
Metaphore and its Sublicensee(s) of such Licensed Product:

          (a)  [***] percent [***] of the Net Sales of such Licensed Product
               generated during the applicable calendar quarter, for Net Sales
               up to [***] and [***] U.S. Dollars (U.S. [***]) for such Licensed
               Product; or

          (b)  [***] percent ([***]%) of the Net Sales of such Licensed Product
               generated during the applicable calendar quarter, for Net Sales
               from [***] U.S. Dollars (U.S. [***]) up through [***] U.S.
               Dollars (U.S.[***]) for such Licensed Product; or

          (c)  [***] percent [***] of the Net Sales of such Licensed Product
               generated during the applicable calendar quarter, for Net Sales
               in excess of [***] U.S. Dollars (U.S. [***]) for such Licensed
               Product.

Metaphore may also direct its Affiliates and/or Sublicensees to pay Pfizer
directly. For the

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED
WITH THE SECURITIES PROMULGATED UNDER THE SECURITIES EXCHANGE ACT OF 1934, AS
AMENDED

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avoidance of doubt, (i) in no event shall a royalty payment be payable under
more than one subsection of this Section 3.1 (i.e., Section 3.1(a), Section
3.1(b) or Section 3.1(C)) at any time during the Term of this Agreement; and
(ii) the Net Sales thresholds used to determine the applicable royalty
percentage pursuant to Section 3.1(a), Section 3.1(b) and Section 3.1(c) shall
be determined on a Licensed Product-by-Licensed Product basis.

     3.2 Timing of Payments. Subject to Section 3.8, all payments due pursuant
to Section 3.1 shall be paid to Pfizer on a quarterly basis within sixty (60)
days following the end of each calendar quarter during the Term of this
Agreement in which such Net Sales are generated by Metaphore or its Affiliates,
or with respect to Net Sales generated by Sublicensees, within sixty (60) days
following the end of the calendar quarter in which Metaphore receives the
applicable payment due to Pfizer under Section 3.1 from such Sublicensees.

     3.3 Length of Royalty Obligations; Reduction in Royalties.

     Subject to the terms and conditions of this Agreement, during the Term of
this Agreement, Metaphore's obligation to pay royalties on Net Sales of a
Licensed Product pursuant to Section 3.1 shall commence on a country-by-country
basis on the date of first commercial sale of a Licensed Product in such country
and shall continue on a country-by-country basis until: (a) expiration in such
country of the last to expire Valid Claim that claims such Licensed Product; or
(b) if there is no Valid Claim in such country that claims such Licensed Product
on the date of first commercial sale of a Licensed Product in such country, but
there is a Valid Claim in the United States that claims such Licensed Product at
the date of first commercial sale in such country, then Metaphore's obligation
to pay royalties on Net Sales of the Licensed Product in such country shall
continue for [***] years after the date of first commercial sale of such
Licensed Product in such country, but the royalty percentage payable pursuant to
Section 3.1 on the Net Sales of the Licensed Product in such country shall be
reduced by [***] percent [***].

     3.4 Payment Reports. Metaphore and/or its Affiliates and/or Sublicensees
shall deliver to Pfizer, within the same time period it is obligated to make the
royalty payment pursuant to Section 3.2, a report that sets out the Net Sales
generated that are subject to the royalty payment payable to Pfizer under
Section 3.2 for the applicable calendar quarter, and the calculation of Net
Sales based on

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED
WITH THE SECURITIES PROMULGATED UNDER THE SECURITIES EXCHANGE ACT OF 1934, AS
AMENDED

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gross invoiced sales of Licensed Products. This obligation shall commence with
the first calendar quarter in which Net Sales are generated by Metaphore or its
Affiliates or a royalty payment is received by Metaphore from a Sublicensee.
With respect to the sales of Licensed Products invoiced or monies received in
U.S. Dollars, the Net Sales and amounts payable shall be expressed in U.S.
Dollars. With respect to sales in the Territory of Licensed Products invoiced or
monies received in a currency other than U.S. Dollars, the Net Sales payable
hereunder shall be expressed in their U.S. Dollar equivalent, calculated as set
forth in Section 3.6.

     3.5 Record Keeping; Audits. Metaphore shall keep, and shall require its
Affiliates and Sublicensees to keep, complete and accurate records of the latest
three (3) years of sales with respect to which Metaphore has an obligation to
make, and/or have made, a royalty payment to Pfizer hereunder. For the sole
purpose of verifying the amount of any payments due to Pfizer hereunder, Pfizer
shall have the right annually at Pfizer's expense to retain an independent,
certified public accountant, selected by Pfizer and reasonably acceptable to
Metaphore to review such records in the location(s) where such records are
maintained by Metaphore or its Sublicensees upon reasonable notice and during
regular business hours and under obligations of strict confidence. Results of
such review shall be made available to both Pfizer and Metaphore; provided that
any information provided by the independent certified public accounting firm to
Pfizer shall be solely limited to any discrepancies and the numerical summary of
any payments due, and Pfizer shall be prohibited from disclosing any such
information to Third Parties. If the review reveals an underpayment of any
royalty payments due and payable to Pfizer hereunder, such underpayment shall be
promptly remitted to Pfizer, together with interest calculated pursuant to
Section 3.7. If the underpayment is equal to or greater than ten percent (10%)
of the amount that was otherwise due pursuant to Section 3.1, Pfizer shall be
entitled to have Metaphore pay all of the reasonable out-of-pocket costs
incurred by Pfizer in connection with such review.

     3.6 Currency and Method of Payments. All payments under this Agreement
shall be made in United States Dollars by wire transfer to such bank account as
Pfizer may designate from time to time. Except where a payment or an amount is
in dispute, and subject to Section 3.8, payments shall be made on or before the
date on which such payment is due pursuant to Section 3.2, and if such day is
not a business day, then on the following business day. Any payments due

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

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hereunder with respect to sales outside of the United States shall be payable,
subject to Section 3.8, in their U.S. Dollar equivalents, calculated using the
closing conversion rate for the last business day of the calendar quarter for
which a payment is payable where such daily closing rates are published by The
Wall Street Journal (or such other reliable source mutually agreed to by the
Parties).

     3.7 Interest; Late Payments. Metaphore shall pay interest to Pfizer on the
aggregate amount of any payments (the payment or amount of which is not in
dispute) that are not paid on or before the date such payments are due under
this Agreement at a rate per annum equal to the lesser of (x) the average prime
rate of interest during the period of delay plus one percent (1%), as published
in The Wall Street Journal (or such other reliable source mutually agreed to by
both Parties) for the next business day after such calculation is made, and (y)
the highest rate permitted by applicable law, calculated on the number of days
such payment is delinquent.

     3.8 Exchange Control. If at any time legal restrictions prevent the prompt
remittance of part or all of any payments payable to Pfizer hereunder with
respect to any country in the Territory where any Licensed Product is sold,
payment shall be made through such lawful means or methods as Metaphore shall
reasonably determine, and such payment shall not be considered late or bear any
interest.

     3.9 Withholding Taxes. Metaphore shall be entitled to deduct from its
payments to Pfizer the amount of any withholding taxes, value-added taxes or
other taxes, levies or charges with respect to such amounts payable by Metaphore
or any of its Affiliates or Sublicensees, or any taxes in each case required by
applicable law to be withheld by Metaphore or any of its Affiliates or
Sublicensees to the extent Metaphore or any of its Affiliates or Sublicensees
pays to the appropriate governmental authority on behalf of Pfizer such taxes,
levies or charges. Metaphore, or if requested by Metaphore, its Affiliate or
Sublicensee, shall deliver to Pfizer, upon Pfizer's request, proof of payment of
all such taxes, levies and other charges and the appropriate documentation which
is necessary to obtain a tax credit, to the extent such tax credit can be
obtained. If and as may be reasonably requested by Metaphore, Pfizer shall
provide assistance to Metaphore and its Sublicensees in seeking any benefits
available to Metaphore or its Sublicensees with respect to government tax
withholdings by any relevant law or double tax treaty. If Pfizer timely
furnishes to Metaphore a document from the appropriate governmental authority
certifying that the applicable payments may be made without

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

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withholding or at a reduced rate of withholding according to any relevant law or
double tax treaty, then Metaphore shall withhold such taxes, levies or charges
at the rate specified in the document.

                     ARTICLE 4: INTELLECTUAL PROPERTY RIGHTS

     4.1 Prosecution, Maintenance and Protection of Intellectual Property
Rights.

          4.1.1 As between Metaphore and Pfizer, Metaphore, and/or its designee,
shall, at Metaphore's cost, have the sole and exclusive right in the Territory
to prosecute and maintain and, subject to Section 4.2, enforce and protect all
Licensed Intellectual Property, and to file Patents covering any Know-How.

          4.1.2 If Metaphore, prior or subsequent to filing any Patent
applications included in the Licensed Intellectual Property elects not to file
or prosecute such Patent applications or maintain any ensuing Patents included
in the Licensed Intellectual Property, Metaphore shall notify Pfizer within a
reasonable period of time prior to allowing such Patents to lapse or become
abandoned or unenforceable, and Pfizer may, at its sole expense, prepare, file,
prosecute, and maintain such Patents provided that Pfizer so notifies Metaphore
in writing within thirty (30) days of Pfizer's receipt of such notice.

          4.1.3 Pfizer shall, at Metaphore's cost, cooperate and assist
Metaphore, and/or its designee, in connection with the preparation, filing,
prosecution, maintenance, enforcement and protection of any Licensed
Intellectual Property, and any Third Party infringement or other Third Party
claim or action that may be asserted (including with respect to the activities
covered by Sections 4.2 and 4.3), as may be reasonably requested by Metaphore
from time to time, including by providing Metaphore with access to applicable
data and information and by executing powers of attorney in favor of Metaphore
and Metaphore's patent counsel and/or designee(s), and by working with and
assisting Metaphore in connection therewith, by taking joint action or sending
joint letters, and by permitting Metaphore to use Pfizer's name as the owner of
the Licensed Intellectual Property in connection with such matters, including in
connection with letters to Third Party's that may be infringing,
misappropriating or otherwise using any of the Licensed Intellectual Property
without authorization.

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

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     4.2 Third Party Infringement.

          4.2.1 Promptly after either Party becomes aware of any actual or
suspected infringement, or any actual or suspected misappropriation or other
unauthorized use, of any Licensed Intellectual Property, such Party shall
provide written notice to the other Party.

          4.2.2 Metaphore shall have the first right, but not the obligation to
decide whether to institute any suit or to take any other action that it
believes may be reasonably required to protect the Licensed Intellectual
Property and Licensed Products in the Territory. If Metaphore does not institute
a suit or take any other action within ninety (90) days after becoming aware or
receiving notice of such infringement or misappropriation or other unauthorized
use pursuant to Section 4.2.1, then, subject to the conditions set forth in this
Section, Pfizer shall have the right, but not the obligation, at its sole
discretion, to institute a suit or take any other action as may be reasonable
and appropriate to protect the Licensed Intellectual Property and Licensed
Products.

          4.2.3 In the event that either Metaphore or Pfizer takes action
pursuant to Section 4.2.2 and without limiting Section 4.1.4, (a) the other
Party shall assist and cooperate with the acting Party to the extent reasonably
possible, as may be reasonably requested by the acting Party from time to time,
including by joining as a party to any suit if necessary or desirable and
requested by the acting Party and by taking joint action or sending joint
letters and jointly participating in any settlement and other similar
conferences; (b) the acting Party shall keep the other Party updated with regard
to any such suit or action; and (c) neither Party shall settle or enter into any
voluntary consent judgment or otherwise compromise any claim or proceeding
without the prior written consent of the other Party (such consent not to be
unreasonably withheld or delayed).

          4.2.4 Each Party shall assume and pay all of its own out-of-pocket
costs incurred in connection with any suit, action or proceeding described in
this Section, including the fees and expenses of such Party's counsel.

          4.2.5 All amounts recovered from a Third Party pursuant to this
Section 4.2 shall be used first to reimburse the reasonable costs and expenses
(including reasonable attorney's fees and costs) incurred by each Party in
initiating or taking action (including any settlement negotiation or proceeding)
as provided in this Section 4.2. Where the amounts recovered do not fully
reimburse the

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

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costs and expenses incurred by the Parties in initiating and taking action as
provided in this Section 4.2. such amounts shall be paid to the Parties on a PRO
RATA basis based upon the costs and expenses incurred by the Parties. Where the
amounts recovered exceed the costs and expenses incurred by the Parties in
initiating and taking action as provided in this Section 4.2, after the Parties
are reimbursed for their respective costs and expenses incurred in initiating
and taking action as provided in this Section 4.2. the remaining amounts from
such recovery shall be allocated as follows:

               (a) if Metaphore initiated and prosecuted the action pursuant to
Section 4.2.2, Metaphore shall receive ninety-five percent (95%) and Pfizer
shall receive five percent (5%) of the balance of such remaining amount; and

               (b) if Pfizer initiated and prosecuted the action pursuant to
Section 4.2.1, Pfizer shall receive ten percent (10%) and Metaphore shall
receive ninety percent (90%) of the balance of such remaining amount.

     4.3 Third Party Claims.

          4.3.1 During the Term, Pfizer shall promptly notify Metaphore in
writing if it becomes aware of:

               (a) any claim or action made or threatened against Pfizer and/or
Metaphore and/or any Sublicensees asserting the invalidity, misuse,
unregistrability, non-infringement or unenforceability of any of the Licensed
Intellectual Property or challenging its or their right to use, or ownership of,
or other right, title or interest in or to, any of the Licensed Intellectual
Property or any other adverse claim of ownership thereof; or

               (b) any pending or threatened claim or action which alleges
Pfizer's or any of its and/or Metaphore's and/or any Sublicensees' activities,
or the conduct of its or their businesses, relating to the Licensed Intellectual
Property have infringed, misappropriated or otherwise violated the intellectual
property rights of any other Person, including in connection with the promotion,
marketing, distribution, manufacture, use, sale, import or offer for sale of any
Licensed Product.

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

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The Parties shall consult as to the appropriate action to defend against any
such claim or action; provided that, as between the Parties, Metaphore shall
have the sole right, but not the obligation, if and as determined by Metaphore
in its sole discretion, to take any action and to control and defend against any
Third Party infringement claims or actions and with respect to any claims or
actions relating to the validity or enforceability of any of the Licensed
Patents or the misappropriation or other unauthorized use of any Licensed
Intellectual Property. Pfizer shall give Metaphore full authority (including the
right to exclusive control of the defense of any such claim or action and the
exclusive right after consultation with Pfizer, to compromise, litigate, settle
or otherwise dispose of any such claim or action), information and assistance
necessary to defend or settle any such claim or action; provided, however, that
Metaphore shall be required to obtain Pfizer's prior consent to such part of any
settlement which requires payment or other action by Pfizer. Pfizer shall
cooperate with Metaphore, at Metaphore's expense, as may be reasonably requested
by Metaphore from time to time, in the defense of any such claim or action
alleging the infringement of the intellectual property rights of a Third Party
by reason of the use of the License Patents in the manufacture, use or sale of
the Licensed Product, including by being joined as a defendant if necessary or
desirable, and by executing all documents and taking all other actions,
including giving testimony, which may reasonably be required in connection with
the prosecution of such claim or action.

          4.3.2 Each Party shall assume and pay all of its own out-of-pocket
costs incurred in connection with any such claim or action described in this
Section, including the fees and expenses of such Party's counsel.

          4.3.3 In the event that Pfizer takes action pursuant to Section 4.3.1
(a) Metaphore shall assist and cooperate with Pfizer to the extent reasonably
possible, as may be reasonably requested by Pfizer from time to time, at
Pfizer's cost; (b) Pfizer shall keep Metaphore updated with regard to any such
suit or action; and (c) Pfizer shall not settle or enter into any voluntary
consent judgment or otherwise compromise any claim or proceeding without the
prior written consent of Metaphore (such consent not to be unreasonably withheld
or delayed).

          4.3.4 Any amounts received from a Third Party pursuant to this Section
4.3, shall be allocated between the Parties in the same manner as set forth in
Section 4.2.5.

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

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     4.4 Certain Deductions. If Metaphore determines that it is necessary or
desirable to seek a license or immunity from suit from any Person in order for
Metaphore (including any of its Affiliates) or any Sublicensees to exercise or
use the rights and licenses granted to Metaphore by Pfizer pursuant to Section
2.1. or if Metaphore (including any Affiliate) or any Sublicensee is otherwise
required to pay to any Person (other than to Pfizer under this Agreement) any
fee, royalty or other payment in connection with the manufacture, use, sale,
import or offer for sale of any Licensed Products in the Territory, then
Metaphore shall have the right to deduct and set off any amounts payable to any
such Persons, including any fee, royalty or other payment, against any amounts
due or payable to Pfizer hereunder, but only up to fifty percent (50%) of each
such amount due or payable to Pfizer hereunder. Such right of offset shall not
in any way limit, and shall be in addition to and not in lieu of, any other
rights, remedies or claims that Metaphore may have under this Agreement or
otherwise.

                    ARTICLE 5: TERM; DEFAULT; AND TERMINATION

     5.1 Term. The term of this Agreement (the "Term") shall commence on the
Effective Date and, unless sooner terminated by mutual agreement of the Parties
or pursuant to Section 5.3, shall terminate upon the expiration of Metaphore's
obligation to pay a royalty to Pfizer as set forth in Section 3.3.

     5.2 Default.

          5.2.1 Notwithstanding Section 5.2.2, if Metaphore commits a material
breach of any of its obligations with respect to an Oral Product under Section
2.3, and fails to cure such breach of Section 2.3 within sixty (60) days after
receiving written notice of such breach from Pfizer, then Pfizer may partially
terminate the license granted to Metaphore pursuant to Section 2.1 solely with
respect to such Oral Product upon giving written notice to Metaphore; provided
that, during such sixty (60) day cure period, if requested by Metaphore, Pfizer
shall in good faith make available to Metaphore a senior executive of Pfizer
that would be an appropriate person to discuss in good faith with a senior
executive of Metaphore the matter of the breach that is the subject of the
notice and any controversy, claim or dispute relating thereto. With the
exception of a partial termination as set forth above in this Section 5.2.1
neither party may terminate this Agreement for breach or for any other.

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED


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reason, in whole or in part (except for Metaphore pursuant to Section 5.3).

          5.2.2 Except as expressly set forth in Section 5.2.1, if either Party
commits a material breach of any material term or condition of this Agreement,
the non-breaching Party may give the other Party written notice of the breach,
and if the breach is not cured within thirty (30) days after receiving written
notice of the breach, the non-breaching Party shall have the right to seek and
obtain any legal or equitable remedies that it may have as a result of such
breach by the other Party of this Agreement. The Parties shall have the right to
seek injunctive or other equitable relief from a court of competent jurisdiction
with respect to any controversy, claim or dispute arising out of or relating to
this Agreement at any time.

          5.2.3 Notwithstanding anything contained in this Agreement, the
Parties hereby acknowledge and agree that in no event shall the Parties have the
right to terminate this Agreement or any rights granted hereunder, in whole or
in part, except for a partial termination of the license as expressly set forth
in Section 5.2.1 with respect to any Oral Product that is the subject of an
uncured breach and for a termination by Metaphore pursuant Section 5.3.

     5.3 Termination by Metaphore. Metaphore may terminate this Agreement at any
time, with or without cause, upon six (6) months advanced written notice to
Pfizer.

     5.4 Effect of Expiration and Termination. Except for termination of this
Agreement by Metaphore pursuant to Section 5.3 or a partial termination of the
license pursuant to Section 5.2.1, upon any termination or expiration of this
Agreement, Metaphore shall have an irrevocable, fully paid-up, fully
transferable and sublicensable, exclusive, perpetual license under the rights
granted to Metaphore pursuant to Section 2.1. Upon a termination of this
Agreement by Metaphore pursuant to Section 5.3. Metaphore and its Sublicensees
shall cease all activities covered by any Valid Claims included in the Licensed
Intellectual Property and using any Know-How that constitutes Confidential
Information of Pfizer (unless or until such Know-How is covered by any of the
exceptions set forth in Section 8.2); provided that, subject to making royalty
payments to Pfizer in accordance with Article 3, Metaphore and its Affiliates
and its and their Sublicensees shall be permitted to continue to operate under
the license granted pursuant to Section 2.1 under the Licensed Intellectual
Property in order to make, have made, use, distribute, promote, market, sell,
offer for sale, import and export any

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED


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Licensed Products in inventory or in production as of the date of such
termination for a period of twelve (12) months after such termination.

     5.5 Survival. Termination or expiration of this Agreement through any means
and for any reason shall not relieve the Parties of any obligation accruing
prior thereto and shall be without prejudice to the rights and remedies of
either Party with respect to any antecedent breach of any of the provisions of
this Agreement. Expiration or termination of this Agreement shall not affect any
rights or obligations of the Parties under this Agreement which are intended by
the Parties to survive such termination. Without limiting the generality of the
foregoing, Articles 7 and 8 and Sections 2.5, 3.5, 5.4, 5.5, 5.6, 6.3 and 6.4
shall survive expiration or termination of this Agreement for any reason, and
Article 4 and Sections 2.1 and 2.2 shall survive expiration or termination of
this Agreement for any reason except for termination of this Agreement by
Metaphore pursuant to Section 5.3.

     5.6 No Damages on Termination. Pfizer shall not be entitled to any
compensation whatsoever as a result of termination of this Agreement by
Metaphore pursuant to Section 5.3, provided, however that, for the avoidance of
doubt, Metaphore will be obligated to pay Pfizer for amounts accrued under
Article 3 prior to the date of any such termination.

                    ARTICLE 6: REPRESENTATIONS AND WARRANTIES

     6.1 Party Representations, Warranties and Certain Covenants. Each Party
hereby represents, warrants and covenants to the other Party that:

          6.1.1 Such Party is a corporation duly organized, validly existing and
in good standing under the laws of Delaware and has the corporate power and
authority to engage in the business such Party is presently engaged in and has
the full right, power and authority, and has obtained all approvals, permits,
consents and licenses necessary, to enter into this Agreement and to perform all
of its obligations hereunder, including, with respect to Pfizer, to grant the
rights and licenses granted to Metaphore pursuant to Section 2.1 (all of which
are exclusive and Metaphore shall not be subject to any limitations or
restrictions in its exercise thereof).

          6.1.2 The execution, delivery and performance of this Agreement by
such Party

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED


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does not and will not (i) violate or breach its certificate of incorporation or
by-laws, (ii) violate or conflict with any applicable laws or regulations, (iii)
violate, breach, cause a default under or otherwise give rise to a right of
termination, cancellation or acceleration with respect to (presently, with the
giving of notice or the passage of time) any agreement to which such Party or
any of its Affiliates is a party or by which any of its assets is bound, or (iv)
result in the creation or imposition of any lien, pledge, mortgage, claim,
charge, or encumbrance upon any assets of such Party or any of its Affiliates.

          6.1.3 This Agreement is a legal and valid obligation binding upon such
Party and is enforceable against it in accordance with its terms and conditions.

     6.2 Pfizer Representations, Warranties and Certain Covenants. Pfizer hereby
represents, warrants and covenants to Metaphore that:

          6.2.1 Neither Pfizer nor its Affiliates have, prior to the Effective
Date, entered into, and Pfizer shall not, and shall ensure that its Affiliates
shall not, following the Effective Date, enter into, any agreement, and have not
granted any now existing, or agreed to grant any future, license, right or
privilege which agreement, license, right or privilege limits or conflicts in
any way with Pfizer's obligations hereunder or otherwise with any of the terms
or conditions of this Agreement.

          6.2.2 Pfizer Inc is the sole and exclusive owner of all right, title
and interest in and to the Licensed Intellectual Property, free and clear of any
liens or other encumbrances.

          6.2.3 Pfizer acquired from Pharmacia all of the intellectual property
and other rights that were subject to or otherwise arose under the Collaborative
Research Agreement that were owned or controlled by Pharmacia prior to such
acquisition, and, after such acquisition, Pfizer has retained all right, title
and interest therein and thereto and has not assigned or otherwise transferred
or granted any right, title or interest, or any options, in or to any such
intellectual property or other rights acquired from Pharmacia except to
Metaphore pursuant to this Agreement.

          6.2.4 No claims of infringement, misappropriation or other conflict
with any intellectual property rights or other rights owned or controlled by any
Third Party have been made or threatened with respect to the Licensed
Intellectual Property or Licensed Products.

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

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     6.3 DISCLAIMER. EACH PARTY HEREBY DISCLAIMS ALL WARRANTIES (OTHER THAN
THOSE SET FORTH IN SECTIONS 6.1 AND 6.2), EXPRESS OR IMPLIED, INCLUDING, THE
IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, OR
FOR PATENTABILITY OR NON-INFRINGEMENT, AND ALL OTHER WARRANTIES.

     6.4 LIMITATION ON DAMAGES. NEITHER PARTY SHALL BE LIABLE TO THE OTHER IN
CONTRACT, TORT OR OTHERWISE FOR ANY SPECIAL, CONSEQUENTIAL OR INDIRECT LOSSES.
THIS LIMITATION SHALL NOT, HOWEVER, LIMIT OR APPLY TO: (I) THE INDEMNITY
OBLIGATIONS SET FORTH IN ARTICLE 7 OF THIS AGREEMENT; (II) ANY LIABILITY OF A
PARTY WITH RESPECT TO ITS BREACH OF ANY OF ITS OBLIGATIONS OF CONFIDENTIALITY
SET FORTH IN ARTICLE 8 OF THIS AGREEMENT; OR (III) ANY LIABILITY OF METAPHORE
WITH RESPECT TO ANY BREACH OF ITS OBLIGATIONS UNDER SECTION 2.3.

                           ARTICLE 7: INDEMNIFICATION

     7.1 Indemnification by Metaphore. Metaphore shall defend, indemnify and
hold harmless Pfizer and its respective officers, directors, employees,
consultants and agents from and against any and all liabilities, costs, damages,
fees, losses and expenses, including reasonable attorneys' fees (collectively,
"Losses"), arising from any Third Party claim or action arising out of, or in
any way attributable to, (a) any breach by Metaphore of any of its
representations, warranties or covenants under this Agreement, or (b) any
personal injury arising from the development, manufacture, use, sale, import or
offer for sale of any Licensed Product by Metaphore and/or its Affiliates,
Sublicensees or collaborators (other than Pfizer or any of its Affiliates or
(sub)licensees or any of its or their respective employees, consultants or
agents); except if and to the extent that such Losses are caused by the
negligence or willful misconduct of Pfizer.

     7.2 Indemnification by Pfizer. Pfizer shall defend, indemnify and hold
harmless Metaphore and its respective officers, directors, employees,
consultants and agents from and against any and all liabilities, costs, damages,
fees, losses and expenses, including reasonable attorneys' fees (collectively,
"Losses"), arising from any Third Party claim or action arising out of, or in
any way

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

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attributable to, (a) any breach by Pfizer of any of its representations,
warranties or covenants under this Agreement, or (b) any personal injury arising
from the development, manufacture, use, sale, import or offer for sale of any
Licensed Product by Pfizer and/or its Affiliates, (sub)licensees or
collaborators (other than Metaphore or any of its Affiliates or Sublicensees or
any of its or their respective employees, consultants or agents), or (c)
Pfizer's research activities conducted under the rights retained pursuant to
Section 2.2; except if and to the extent that such Losses are caused by the
negligence or willful misconduct of Metaphore.

     7.3 Procedures. The indemnities set forth in this Article 7 are subject to
the condition that the Party seeking indemnity shall forthwith notify the other
Party on being notified or otherwise made aware of a suit, action or claim
against a member of the indemnified Party indemnitees, as applicable, (provided
that the failure to so notify an indemnifying Party shall not affect the
obligations of the indemnifying Party hereunder unless the indemnifying Party is
actually prejudiced by such failure), and that the indemnifying Party defend and
control any proceedings with the other Party being permitted to participate at
its own expense (unless there shall be a conflict of interest which would
prevent representation by joint counsel, in which event the indemnifying Party
shall pay for the other Party's counsel); provided that any settlement or
voluntary consent judgment shall not be entered into without the consent of the
indemnified Party, such consent not to be unreasonably withheld. The Parties
shall cooperate in the defense of any Third Party claim. An indemnifying Party
shall not be responsible for the indemnification of any member of the
indemnified Party's indemnitees arising from any negligent or intentional acts
by any such indemnitees.

                           ARTICLE 8: CONFIDENTIALITY

     8.1 Confidential Information. During the Term of this Agreement and for
five (5) years thereafter without regard to the means of termination or
expiration, except as expressly permitted herein and subject to Section 8.2.
neither Pfizer nor Metaphore shall use, for any purpose other than the purpose
of this Agreement, or reveal or disclose to any Third Party information or
materials disclosed by the other Party, including information provided by a
Party to the other Party prior to the Effective Date (and including all
information provided under the Collaborative Research Agreement), and marked as
confidential, or if disclosed or obtained orally or visually (or otherwise in a
non-written form), which was described or summarized in a writing or other
tangible form and


[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

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identified as "confidential" and forwarded to the receiving Party within thirty
(30) days of such disclosure (collectively, "Confidential Information"), without
first obtaining the prior written consent of the other Party. Notwithstanding
the foregoing, all materials, information and data disclosed to Pfizer
(including to its predecessors, Pharmacia Corporation or the Monsanto Company)
by or on behalf of Metaphore (including any Indication Data Packages (as such
term is defined under the Collaborative Research Agreement)) shall be considered
Confidential Information of Metaphore and Pfizer shall not have any right to use
any such materials, information or data without first obtaining the prior
written consent of Metaphore. In addition, Pfizer shall not disclose any
Know-How or any other information relating to any of the Licensed Intellectual
Property or Licensed Products to any Third Party without first obtaining the
prior written consent of Metaphore and shall not use any Know-How except as
permitted pursuant to Section 2.2, and all such information shall be deemed to
be Confidential Information of Metaphore during the Term.

     8.2 Exceptions. This confidentiality obligation shall not apply to
information which (a) is or becomes a matter of public knowledge through no
fault of the receiving Party; (b) is already in the possession of the receiving
Party without obligation of confidentiality at the time of the disclosure by the
disclosing Party; or (c) is disclosed non-confidentially to the receiving Party
by a Third Party having the right to do so. The Parties shall take the same
measures as it would take for its own confidential information to assure that no
unauthorized use or disclosure is made by other Persons to whom access to such
information is granted. In addition, and notwithstanding anything contained in
this Article 8, a Party may disclose Confidential Information of the other Party
and make other disclosures if required by applicable law, rule, regulation,
government requirement and/or court order, including as may be required in
connection with any filings made with, or by the disclosure policies of a major
stock exchange; provided that, the disclosing Party promptly notifies the other
Party of any such requirement and, to the extent it is reasonably able to do so,
provides the other Party a reasonable opportunity to seek a protective order or
other appropriate remedy and/or to waive compliance with the provisions of this
Agreement. In addition, Metaphore may disclose Confidential Information of
Pfizer in connection with filings with, and disclosures or submissions to, or
any inspections or inquiries by, any regulatory or other governmental agency in
the Territory in connection with securing regulatory, pricing or other
approvals in the Territory.

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

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     8.3 Certain Obligations. During the Term of this Agreement and for a period
of five (5) years thereafter and subject to the exceptions set forth in Section
8.2, Metaphore and Pfizer agree:

          (a)  to use Confidential Information of the other Party only for the
               purposes contemplated under this Agreement;

          (b)  to treat the Confidential Information of the other Party as it
               would its own confidential information; and

          (c)  to take all reasonable precautions to prevent the disclosure to
               the Confidential Information of the other Party to a Third Party
               without written consent of the other Party and to only disclose
               the Confidential Information of the other Party to those
               Affiliates, and to those employees, consultants and agents of its
               and its Affiliates, who have a need to know such Confidential
               Information for the purposes set forth herein and who are bound
               by and subject to written obligations of confidentiality
               substantially similar to, or more stringent than, those set forth
               herein; except that in the case of Metaphore, Metaphore may
               provide Confidential Information of Pfizer relating to a Licensed
               Product (including with respect to the development, marketing
               promotion, manufacturing, distribution, sale and/or
               commercialization thereof) to Metaphore's (sub)licensees,
               distributors, collaborators, investors and partners (and to any
               potential (sub)licensees, distributors, collaborators, investors
               and partners) and to Metaphore's legal and financial and other
               representatives and advisors in connection with the exercise of
               the license and other rights granted to Metaphore and its
               Affiliates under this Agreement, the conduct of its business
               and/or any actual or potential sale, merger or transfer of all or
               substantially all of its assets or any other acquisition of
               Metaphore or any of its assets, provided that such Persons are
               bound by and subject to written obligations of confidentiality
               substantially similar to, or more stringent than, those set forth
               herein.

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

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     8.4 Press Releases, Disclosures and Public Announcements. Neither Party
shall issue any press release or other publicity materials with respect to this
Agreement without the prior written consent of the other Party (such consent not
to be unreasonably withheld or delayed), provided that either Party shall have
the right thereafter to issue any press release or other publicity materials
that contains information or statements that are substantially similar to those
contained in any press release or other publicity materials for which the other
Party has already given its consent. This restriction shall not apply to
disclosures required by any law, rule or regulation, including as may be
required in connection with any filings made with, or by the disclosure policies
of a major stock exchange; provided that, the disclosing Party promptly notifies
the other Party of any such requirement and, to the extent it is reasonably able
to do so, provides the other Party a reasonable opportunity to seek a protective
order or other appropriate remedy and/or to waive compliance with the provisions
of this Agreement.

     8.5 Return; and Permitted Uses. Upon termination or expiration of this
Agreement and upon the request of the disclosing Party, the receiving Party
shall promptly return to the disclosing Party, or destroy, as requested by the
disclosing Party, all copies of Confidential Information received from such
Party (and document the destruction thereof); except that each Party shall be
permitted to retain a copy (or copies, as necessary) of such Confidential
Information for the purpose of compliance with this Agreement or as may be
required by any law or regulation or as may be necessary for regulatory
purposes. Notwithstanding the foregoing or anything contained in this Agreement,
Metaphore and its Affiliates may use Confidential Information of Pfizer
(including, for the avoidance of doubt, any Confidential Information received
from Pharmacia Corporation or the Monsanto Company under the Collaborative
Research Agreement) during and after the Term of this Agreement unless Metaphore
terminates this Agreement pursuant to Section 5.3.

     8.6 Termination. If this Agreement is terminated or expires, neither Party
shall disclose to any Third Party any reason for such termination or for not
proceeding with this Agreement without the express written consent of the other
Party, and the Parties shall agree upon statements for public disclosure, such
agreement not to be unreasonably withheld or delayed.

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

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                            ARTICLE 9: MISCELLANEOUS

     9.1 Assignment and Delegation. This Agreement shall not be assignable by
either Party without the prior written consent of the other Party, except to an
Affiliate or to any successor of the assigning Party, or in connection with the
sale, merger or transfer of all or substantially all of its assets. Any transfer
or assignment of this Agreement in violation of this Section 9.1 shall be null
and void ab initio. Subject to the foregoing, this Agreement shall be binding
upon and inure to the benefit of, and be enforceable by the Parties hereto and
their respective permitted successors and assigns.

     9.2 Termination of Collaborative Research Agreement. The Parties hereby
agree that the Collaborative Research Agreement is hereby terminated in its
entirety immediately and automatically as of the Effective Date, and that
notwithstanding any provisions of the Collaborative Research Agreement, no terms
or conditions of such agreement shall survive termination thereof.

     9.3 Entire Agreement; Compliance. This Agreement, and the Exhibit attached
hereto, constitute the entire agreement between the Parties with respect to the
subject matter hereof, and supersede all previous arrangements with respect to
the subject matter hereof, whether written or oral, including the Collaborative
Research Agreement.

     9.4 Amendments. Any amendment or modification to this Agreement shall be
made in writing signed by both Parties.

     9.5 Governing Law. This Agreement shall be construed and the respective
rights of the Parties hereto determined according to the substantive laws of the
State of Delaware (other than with respect to its conflict of law rules), except
matters of intellectual property law which shall be determined in accordance
with the intellectual property laws of the United States or other jurisdiction
relevant to the intellectual property in question. The United Nations Convention
on Contracts for the International Sale of Goods shall have no application to
this Agreement and is hereby excluded.

     9.6 Force Majeure. No failure or omission by the Parties hereto in the
performance of any obligation of this Agreement shall be deemed a breach of this
Agreement or create any liability if the same shall arise from any cause or
causes beyond the control of the Parties, including, the following:

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

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acts of God, acts or omissions of any government, any rules, regulations or
orders issued by any governmental authority or by any officer, department,
agency or instrumentality thereof, equipment or machinery breakdown, strike, or
any labor disturbance (regardless of the reasonableness of the demands of
labor), civil commotions, regulations, or directions of any governmental entity,
voluntary or mandatory compliance with any request of any governmental entity,
facility shut down, voluntary or mandatory compliance with any request for
material represented to be for purposes of (directly or indirectly) producing
articles for national defense or national defense facilities, shortage of labor,
fuel, power or raw materials, inability to obtain raw materials or supplies,
failures of normal sources of supplies, inability to obtain or delays of
transportation facilities, fire, storm, flood, earthquake, accident, explosion,
sabotage, war, terrorism, rebellion, insurrection, riot, and invasion (or the
threat of any of the foregoing), provided that (i) the affected Party shall
promptly notify the other Party in writing, and (ii) such failure or omission
resulting from one of the above causes is cured as soon as is practicable after
the occurrence of one or more of the above-mentioned causes.

     9.7 Severability. If any provision hereof should be held invalid, illegal
or unenforceable in any respect in any jurisdiction, then such provision shall
be of no effect, and, to the fullest extent permitted by law, (a) all other
provisions hereof shall remain in full force and effect in such jurisdiction and
shall be liberally construed in order to carry out the intentions of the Parties
as nearly as may be possible, (b) such invalidity, illegality or
unenforceability shall not affect the validity, legality or enforceability of
such provision in any other jurisdiction, and (c) the Parties shall negotiate in
good faith to replace such provision with a provision which effects to the
extent possible the original intent of such provision. To the extent permitted
by applicable law, Pfizer and Metaphore hereby waive any provision of law that
would render any provision hereof, prohibited or unenforceable in any respect.

     9.8 Notice. Any notices and communications hereunder shall be in writing in
the English language, shall be deemed made and effective on receipt, and shall
be sent either (i) in person, (ii) by registered or certified United States
Mail, postage prepaid and return receipt requested, or (iii) by overnight
courier service, and addressed to the Party to receive such notice or
communication at the address given below, or such other address as may hereafter
be designated by notice in writing:

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

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                                                                  EXECUTION COPY

     Notices to Metaphore:

     Metaphore Pharmaceuticals, Inc.
     One Bridge Plaza, Suite 500
     Fort Lee, New Jersey 07024
     Attention: President and CEO

     Notices to Pfizer:                         with a copy to:

     Pfizer Global R&D Headquarters             Pfizer Global R&D Headquarters
     50 Pequot Avenue                           50 Pequot Avenue
     New London, Connecticut 06320              New London, Connecticut 06320
     Attention: Executive Vice President, PGRD  Attention: General Counsel, PGRD

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

     9.9 Independent Contractor. It is understood and agreed that the
relationship between the Parties hereunder is that of independent contractors
and that nothing in this Agreement shall be construed to create any relationship
of agency, partnership or joint venture or any fiduciary relationship between
the Parties or as authorization for either Pfizer, on the one hand, or
Metaphore, on the other hand, to act as agent for the other. Neither Party shall
have the authority to bind the other Party or the other Party's representatives
in any way.

     9.10 Waiver. No failure on the part of Pfizer or Metaphore to exercise, and
no delay in exercising, any right, power, remedy or privilege under this
Agreement, or provided by statute or at law or in equity or otherwise, shall
operate to impair, prejudice, constitute or be deemed to constitute a waiver of
any such right, power, remedy or privilege or be construed as a waiver to any
breach of this Agreement or as an acquiescence therein, nor shall any single or
partial exercise of any such right, power, remedy or privilege preclude any
other or further exercise thereof or the exercise of any other right, power,
remedy or privilege. No waiver of this Agreement or any provision hereof shall
be enforceable against any Party hereto unless in writing, signed by the Party
against whom such waiver is claimed, and shall be limited solely to the one
event.

     9.11 Interpretation. This Agreement has been prepared jointly and shall not
be strictly construed against either Party. The captions or headings of the
sections or other subdivisions hereof are inserted only as a matter of
convenience or for reference and shall have no effect on the meaning of the
provisions hereof. In this Agreement, the singular shall include the plural and
vice versa and

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

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                                                                  EXECUTION COPY

the word "including" or "included" shall be deemed to be followed by the phrase
"without limitation."

     9.12 No Third Party Beneficiaries. No person or entity other than Metaphore
and Pfizer and Metaphore's Affiliates and permitted Sublicensees and assignees
hereunder shall be deemed an intended beneficiary hereunder or have any right to
enforce any obligation of this Agreement.

     9.13 License Survival During Bankruptcy. All rights and licenses granted
under or pursuant to this Agreement are, and shall otherwise be deemed to be,
for purposes of Paragraph 365(n) of the U.S. Bankruptcy Code, licenses of rights
to "intellectual property" as defined under Paragraph 101(35A) of the U.S.
Bankruptcy Code. The Parties agree that Metaphore, as a licensee of such rights
under this Agreement, shall retain and may fully exercise all of its rights and
elections under the U.S. Bankruptcy Code. The Parties further agree that, in the
event of the commencement of a bankruptcy proceeding by or against Pfizer
including under the U.S. Bankruptcy Code, Metaphore shall be entitled to a
complete duplicate of (or complete access to, as appropriate) any such
intellectual property and all embodiments of such intellectual property,
including Know-How, and the same, if not already in Metaphore's possession,
shall be promptly delivered to Metaphore upon any such commencement of a
bankruptcy proceeding upon written request therefore by Metaphore.

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

                                    * * * * *

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2. PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

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                                                                  EXECUTION COPY

     IN WITNESS WHEREOF, the Parties have executed this Agreement by their duly
authorized representative.

METAPHORE PHARMACEUTICALS, INC.         PFIZER INC.


By: /s/ Alan W. Dunton                  By: /s/ Alan R. Proctor
    ---------------------------------       -----------------------------------
Name: Alan W. Dunton, M.D.              Name: Alan R. Proctor
Title: President + CEO                  Title: VP. Strategic Alliances

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2. PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

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                                                                  EXECUTION COPY

                                    EXHIBIT A

                                  PATENT RIGHTS

                                Attached hereto.

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2. PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

License Agreement between Metaphore Pharmaceuticals, Inc. and Pfizer Inc.


                                   Exhibit A

<Page>

METAPHORE, INC.                                                     CONFIDENTIAL

                                    EXHIBIT A

                                  PATENT RIGHTS

COUNTRY          PATENT NO.   ISSUE DATE
-------          ----------   ----------

  ANALGESIC METHODS USING SYNTHETIC CATALYSTS FOR THE DISMUTATION OF SUPEROXIDE
                                    RADICALS

AUSTRALIA        733,415      8/30/2001
UNITED STATES    6,180,620    1/30/2001
UNITED STATES    6,214,817    4/10/2001
UNITED STATES    6,395,725    5/28/2002

         MANGANESE COMPLEXES OF NITROGEN-CONTAINING MACROCYCLIC LIGANDS
               EFFECTIVE AS CATALYSTS FOR DISMUTATING SUPEROXIDE

UNITED STATES    5,874,421    2/23/1999
UNITED STATES    6,204,259    3/20/2001
UNITED STATES    6,084,093    7/4/2000
UNITED STATES    5,637,578    6/10/1997
UNITED STATES    5,610,293    3/11/1997
AUSTRIA          0598753      3/18/1998
AUSTRALIA        661023       10/31/1995
BELGIUM          0598753      3/18/1998
SWITZERLAND      0598753      3/18/1998
GERMANY          69224839.0   3/18/1998
DENMARK          0598753      3/18/1998
SPAIN            0598753      3/18/1998
FRANCE           0598753      3/18/1998
UNITED KINGDOM   0598753      3/18/1998
GREECE           3027158      3/18/1998
ITALY            0598753      3/18/1998
JAPAN            3155552      2/2/2001
SOUTH KOREA      154346       7/9/1998
SOUTH KOREA      145953       5/6/1998
LUXEMBOURG       0598753      3/18/1998
NETHERLANDS      0598753      3/18/1998
PORTUGAL         0598753      3/18/1998
SWEDEN           0598753      3/18/1998
NEW ZEALAND      272364       6/17/1996
SOUTH AFRICA     92/5139      6/30/1993

         MANGANESE OR IRON COMPLEXES OF NITROGEN-CONTAINING MACROCYCLIC
           LIGANDS EFFECTIVE AS CATALYSTS FOR DISMUTATING SUPEROXIDE

UNITED STATES    6,525,041    2/25/2003

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934 AS AMENDED

<Page>

METAPHORE, INC.                                                     CONFIDENTIAL

COUNTRY          PATENT NO.   ISSUE DATE
-------          ----------   ----------

     METHODS OF DIAGNOSTIC IMAGE ANALYSIS USING METAL COMPLEXES OF NITROGEN-
                         CONTAINING MACROCYCLIC LIGANDS

UNITED STATES    5,976,498    11/2/1999

    METHODS OF USE FOR PEROXYNITRITE DECOMPOSITION CATALYSTS, PHARMACEUTICAL
                              COMPOSITIONS THEREFOR

UNITED STATES    6,245,758    6/12/2001
NEW ZEALAND      285648       06/08/2000
MEXICO           215808       8/15/2003

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED


                                        2

<Page>

METAPHORE, INC.                                                     CONFIDENTIAL

                               PATENT APPLICATIONS

COUNTRY          SERIAL NO.    FILING DATE
-------          ----------    -----------

  ANALGESIC METHODS USING SYNTHETIC CATALYSTS FOR THE DISMUTATION OF SUPEROXIDE
                                    RADICALS

AUSTRALIA        77024/00       9/14/2000
CANADA           2294155        6/15/1998
CANADA           2382105        9/14/2000
EPO              98929022.6     6/15/1998
EPO              00966722.1     9/14/2000
JAPAN            504593/1999    6/15/1998
JAPAN            2001-523400    9/14/2000
UNITED STATES    09/997,974(1)  11/30/2001
HONKONG          02108379.2     9/14/2000

   MANGANESE COMPLEXES OF NITROGEN-CONTAINING MACROCYCLIC LIGANDS EFFECTIVE AS
                      CATALYSTS FOR DISMUTATING SUPEROXIDE

CANADA           2072934           7/2/1992
IRELAND          922211            7/7/1992

 ANALYTICAL METHOD FOR THE DETECTION AND QUANTIFICATION OF SUPEROXIDE DISMUTASE
                     MIMETIC COMPOUNDS IN BIOLOGICAL FLUIDS

UNITED STATES    09/809,903        3/16/2001

    COMBINATION THERAPY OF AN SODM AND A CORTICOSTEROID FOR PREVENTION AND/OR
                        TREATMENT OF INFLAMMATORY DISEASE

WIPO             PCT/US02/20476(2) 6/26/2002

 METHODS OF DIAGNOSTIC IMAGE ANALYSIS USING BIOCONJUGATES OF METAL COMPLEXES OF
                     NITROGEN-CONTAINING MACROCYCLIC LIGANDS

UNITED STATES    10/405,044        4/1/2003

 COMPOSITIONS COMPRISING A CATALYSTS FOR THE DISMUTATION OF SUPEROXIDE AND USE
           OF THE COMPOSITION FOR PREVENTING AND TREATING HYPOTENSION

EUROPE           01977901.6        10/5/2001
AUSTRALIA        2001296984        10/5/2001
JAPAN            2002-532215       10/5/2001
CANADA           2425266           10/5/2001
UNITED STATES    10/398,705        4/7/2003

----------
(1)  Jointly owned by Pharmacia Corporation and Metaphore Pharmaceuticals, Inc.

(2)  Jointly owned by Monsanto Company and Metaphore Pharmaceuticals, Inc.

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED


                                        3

<Page>

METAPHORE, INC.                                                     CONFIDENTIAL

COUNTRY          SERIAL NO.    FILING DATE
-------------   ------------   -----------
             BIOMATERIALS MODIFIED WITH SUPEROXIDE DISMUTASE MIMICS

UNITED STATES   09/580007        5/26/2000
EUROPE          00932810.5       5/26/2000
CANADA          2374472          5/26/2000
JAPAN           2000-620999      5/26/2000

           METHODS OF USE FOR PEROXYNITRITE DECOMPOSITION CATALYSTS,
                     PHARMACEUTICAL COMPOSITIONS THEREFOR

BRAZIL          PI 9507643.3    05/09/1995
CANADA          2189528         05/09/1995
CHINA           95194075.9      05/09/1995
FINLAND         964537          05/09/1995
HUNGARY         P9603140        05/09/1995
JAPAN           529755/95       05/09/1995
UNITED STATES   09/930,433      08/15/2001

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED


                                        4

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                         AMENDMENT TO LICENSE AGREEMENT

     This AMENDMENT TO LICENSE AGREEMENT ("Amendment") is made and entered into
as of the 25th day of May, 2006 by and between ActivBiotics, Inc., a Delaware
corporation with offices at 110 Hartwell Avenue, Lexington, Massachusetts 02421
(ActivBiotics Inc., together with its affiliates, "ABI"), and PFIZER INC., a
Delaware corporation, with offices at 235 East 42nd Street, New York, New York
10017 (Pfizer Inc., together with its affiliates, "Pfizer"). ABI and Pfizer are
each referred to herein individually, as a "Party" and collectively, as the
"Parties".

                                   WITNESSETH:

     WHEREAS ABI (as the successor to Metaphore Pharmaceuticals, Inc.,
"Metaphore") and Pfizer are parties to that certain License Agreement dated
December 19, 2003 ("License") granting an exclusive license to Metaphore to the
Know How and Patent Rights defined in said License;

     WHEREAS Metaphore and Aeolus Pharmaceuticals, Inc. ("Aeolus") are engaged
in a patent interference, Interference 105,388 pending before the Board of
Patent Appeals and Interferences of the U.S. Patent and Trademark Office (the
"interference"), declared November 23, 2005 between Stern et al, U.S. Pat.
Reissue Appln. No. 09/930,433, based on U.S. Pat. No. 6,245,758 (owned by
Pfizer, party in interest Metaphore) and Fridovich et al, U.S. Pat. No.
6,103,714 (owned by Duke University, parties in interest, Duke University and
Aeolus Pharmaceuticals, Inc.);

     WHEREAS ABI, upon acquisition of Metaphore, desired to terminate the
interference with Aeolus and sought Pfizer's approval to settle with Aeolus by
abandoning U.S. Pat. Reissue Appln. No. 09/930,433, reviving U.S. Pat. No.
6,245,758 (the "758 patent"), and agreeing to a mutual release and
cross-license with Aeolus; and

     WHEREAS ABI sought Pfizer's further approval to accept a proposed
settlement payment and a capped royalty from Aeolus based on net sales of any
products and/or services sold by Aeolus, and/or its sub-licensees, for which
products and/or services are covered by any claims contained in U.S. Pat. No.
6,245,758 and seeks to amend the License to accommodate the settlement terms.

     NOW, THEREFORE, in consideration of the mutual covenants herein contained,
and for other good and valuable consideration, the amount and sufficiency of
which are hereby acknowledged, the Parties hereby agree as follows:

     With Pfizer's agreement to the settlement terms of the interference between
ABI and Aeolus, Pfizer and ABI agree to add new subsection Section 3.1.1 to the
Royalties section of the Agreement to describe the special royalty terms for
products subject to the interference:

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

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    3.1.1 Special Compensation from ABI in Regard to Patent Interference
          Settlement with Aeolus Pharmaceuticals, Inc. ABI agrees to share any
          revenue, whether in the form of a royalty, a milestone payment, or any
          other form of compensation, received from Aeolus based on compounds
          arising out of the '758 patent, or on any agreement involving the
          settlement of the interference, on a [***] basis. The terms of the
          settlement between ABI and Aeolus are set forth in Exhibit B. Any
          modification of the terms of the interference settlement would require
          Pfizer's prior written approval.

The remaining terms and conditions set forth in the Agreement will remain in
full force and effect and binding on ABI and Pfizer.

                                      *****

     IN WITNESS WHEREOF, the Parties have executed this Agreement by their duly
authorized representative.

ACTIVBIOTICS, INC.                      PFIZER INC.


By: /s/ Steven C. Gilman, Ph.D.         By: /s/ B. J. Bormann, Ph.D.
    ---------------------------------       ------------------------------------
Name: Steven C. Gilman, Ph.D.           Name: B. J. Bormann, Ph.D.
Title: President & CEO                  Title: Vice President, PGRD

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 PROMULGATED UNDER THE
SECURITIES EXCHANGE ACT OF 1934, AS AMENDED.