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                                                                    Exhibit 10.8

                      "CONFIDENTIAL TREATMENT REQUESTED BY
                              ACTIVBIOTICS, INC."

                            CONFIDENTIAL INFORMATION

                           EXCLUSIVE LICENSE AGREEMENT
                                     BETWEEN
                               ACTIVBIOTICS, INC.
                                       AND
                            UNIVERSITY OF WASHINGTON

THIS EXCLUSIVE LICENSE AGREEMENT ("Agreement") is entered into on May 16, 2003
("Effective Date") by and between ActivBiotics, Inc, a Delaware corporation with
its principal place of business at 128 Spring Street, Lexington, MA ("Licensee")
and the University of Washington, a public institution of higher education and
an agency of the state of Washington, acting through its Office of Technology
Licensing ("OTL"), with administrative offices at 4311 11th Avenue NE, Suite
500, Seattle, WA 98105 ("University") (individually the "Party" or collectively
the "Parties").

                                    RECITALS

Whereas, University has developed and owns or is in possession of certain
technology relating to diagnosis and treatment of arterial chlamydial granuloma,
described in OTL# 1168-1291129DL ("UW Technology" as defined below) and
developed by Dr(s) Cho Cho Kuo, Allan Shor, Dorothy L. Patton, Lee Ann Campbell
and J Thomas Grayston;

Whereas, University and Licensee entered into an Exclusive Option Agreement
dated June 13, 2002 ("Exclusive Option Agreement Between ActivBiotics, Inc. and
the University of Washington" attached hereto as Exhibit A and incorporated
herein by reference), which remains in full force and effect;

Whereas, University desires that UW Technology be used as broadly and as soon as
possible in the public interest, and to this end desires to exclusively license
UW Technology to a company capable of commercially exploiting UW Patent Rights
(as defined below);

Whereas, Licensee wishes to obtain a license to UW Patent Rights and Licensee is
under no contractual or other obligation which encumber, restrict, or limit any
of the rights granted by University under this Agreement, and is committed to
commercially exploiting UW Patent Rights; and

Whereas, University is willing to grant such a license to Licensee in order that
Licensed Product(s) (as defined below) be made available on the commercial
market.

Now Therefore, in consideration of the mutual promises set forth herein, and
other good and valuable consideration, the receipt and sufficiency of which is
hereby expressly acknowledged, the Parties hereto, intending to be legally
bound, hereby agree as follows:

1.0 DEFINITIONS

[***] 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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                            CONFIDENTIAL INFORMATION

1.1 All capitalized terms used in this Agreement have the respective meanings
ascribed to them in this Agreement and, unless indicated otherwise, are intended
to include all derivative forms of the terms.

1.2 "Affiliate" means any entity that directly or indirectly controls, is
controlled by, or is under common control with Licensee. For the purposes of
this Paragraph 1.2 "control" means either the right to exercise more than 50% of
the voting rights of an entity, including but not limited to, a controlled
corporation or limited liability company or the power to direct or cause the
direction of the management or policies of any other controlled entity.
Affiliates shall mean only those companies listed on Exhibit 1.2, attached
hereto and incorporated herein by reference, which may be amended from time to
time only with prior written consent of an authorized representative of the
University.

1.3 "Combination Product" shall mean any subject matter sold at a single price,
including but not limited to, products and processes, containing both a
component that constitutes a Licensed Product and one or more other active
components that do not constitute Licensed Product.

1.4 "Confidential Information" means any information and materials of the
University (biological, chemical, or otherwise) not generally known to the
public. Confidential Information may be conveyed in written, graphic, oral,
physical, or electronic form. Confidential Information shall include, without
limitation, UW Technology Rights. Notwithstanding the foregoing, Licensee shall
have no obligation of confidentiality relating to:

     1.4.1 any information of the University that is required to be disclosed by
     judicial or legislative action or government regulation;

     1.4.2 any information that is or becomes part of the public domain through
     no fault of Licensee;

     1.4.3 any information that is known to Licensee prior to the disclosure by
     University, as evidenced by documentation;

     1.4.4 any information that is publicly released as authorized under this
     Agreement by University, its employees or agents;

     1.4.5 any information that is subsequently obtained by Licensee from a duly
     authorized Third Party; or

     1.4.6 any information that is independently developed by Licensee without
     reliance on any portion of the Confidential Information received from
     University and without any breach of this Agreement as evidenced by
     documentation.

1.5 "Field of Use" means diagnosis and treatment of arterial chlamydial
granuloma, which includes related arterial and coronary diseases or disorders
caused by or influenced by arterial chlamydia granuloma lesions and infections.

[***] 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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1.6 "Licensed Product" means a product or service, including but not limited to
products, services and processes, which are covered within UW Patent Rights
and/or UW Technology Rights.

1.7 "Licensed Territory" means worldwide.

1.8 "Net Sales" means the gross billed or invoiced amounts for Licensed
Product(s) or Combination Product(s) less discounts and allowances given and
actually taken and which are customary in Licensee's trade, other than those
which permit a reduction in payment by the customer in exchange for early
payment. Notwithstanding the foregoing, Net Sales will not be less than [***]%
of gross billed or invoiced amounts. In the event that Licensed Product(s) or
Combination Product(s) are sold to an Affiliate, then Net Sales shall be the
price which would have been charged if the Licensed Product(s) or Combination
Product(s) in question had been sold on normal terms and conditions to a
purchaser dealing at arm's length with Licensee. Licensed Product(s) and/or
Combination Product(s) shall be deemed "sold" when billed or invoiced, whichever
occurs first.

1.9 "Semi-Annual Period" means a period of six consecutive calendar months
beginning on the first day of either January or July.

1.10 "Sublicense" means the present, future or contingent transfer by Licensee
to a Third Party of any license, right, option, first right to negotiate or
other right granted under the UW Patent Rights and/or UW Technology Rights, in
whole or in part. Sublicense shall include, without limitation, such transfer to
strategic partners and marketing collaborators.

1.11 "Sublicensee" means a Third Party holding a Sublicense under the UW Patent
Rights and/or UW Technology Rights.

1.12 "Sublicensing Fee" means any license fee or non-royalty consideration,
including equity, received by Licensee from a Sublicensee for the grant of a
license to make, have made, use or distribute Licensed Products or Combination
Products and that is not included in Net Sales.

1.13 "Sublicensing Consideration" means cash or non-cash consideration of any
kind received by Licensee or Affiliate from a Sublicensee(s) for the grant of a
Sublicense under this Agreement, including, but not limited to, upfront fees or
milestone fees and including any premium paid by the Sublicensee(s) over Fair
Market Value (hereinafter defined) for stock of the Licensee or an Affiliate in
consideration for such Sublicense. However, not included in such Sublicensing
Consideration are amounts paid to the Licensee or an Affiliate by the
Sublicensee(s) for earned royalties on Licensed Product(s), product development,
research work, clinical studies, and regulatory approvals performed by or for
the Licensee or Affiliate, or third parties on their behalf pursuant to a
specific agreement including a performance plan and commensurate budget "Fair
Market Value" means the average price that the stock in question is publicly
trading at for twenty (20) days prior to the announcement of its purchase by the
Sublicensee(s), or, if the stock is not publicly traded, the value of such stock
as determined by the most recent private financing through a financial investor
(an entity whose sole interest in the Licensee or Affiliate is financial) of the
Licensee or Affiliate that issue the shares

[***] 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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1.14 "Technical Information" means any technical facts, data, or advice, oral or
written (in the form of information contained in patents and patent
applications, reports, letters, drawings, specifications, testing procedures,
training and operational manuals, bills of materials, photographs and related
materials), and/or any tangible material(s), not covered by but reasonably
necessary for practicing UW Patent Rights and developed by UW Researchers before
the Effective Date which is owned by and in possession of University and is not
covered by Third Party rights that would prevent delivery to Licensee.

1.15 "Third Party" means all individuals or entities other than University,
Licensee and Affiliates.

1.16 "UW Researchers" means Dr(s) Cho Cho Kuo, Allan Shor, Dorothy L Patton, Lee
Ann Campbell and J. Thomas Grayston.

1.17 "UW Patent Rights" shall mean the United States issued patents, United
States or international patent application(s) listed in Exhibit 1.16 and any
corresponding patent issued therefrom, including all reissues, divisionals,
continuations, reexaminations and extensions thereof, together with all
corresponding foreign patents, extensions, supplemental protection certificates
and applications corresponding thereto now issued or issued during the term of
this Agreement and which directly relate to UW Technology. Continuations-in-Part
("CIP") Patent Applications will be included with UW Patent Rights only if
Licensee substantially funds the research that results in the filing of a CIP. A
patent or patent application shall cease to be a UW Patent Right when any of the
following occur: a) it expires; b) it is abandoned; or c) it is held to be
invalid or unenforceable by a court of competent jurisdiction from which no
appeal can be taken.

1.18 "UW Technology" means the technology as developed in the University
laboratories of UW Researchers and as described in OTL File # 1168-1291129DL.

1.19 "UW Technology Rights" means UW Technology and Technical Information all of
which is the proprietary information of the University.

2.0 GRANT OF RIGHTS

2.1 Grant. Subject to Licensee's fulfillment of its obligations under this
Agreement, University hereby grants to Licensee an exclusive, royalty-bearing
license, with the right to Sublicense as further set forth in Article 3.0
(Sublicensing), under the UW Patent Rights and/or UW Technology Rights to
import, make, have made, use, sell, offer for sale and have sold Licensed
Product(s) and Combination Product(s) in the Licensed Territory in the Field of
Use.

2.2 University Reserved Rights. The license granted above is subject to a
reserved non exclusive license by University to make, have made, and use
products, processes, or other subject matter covered by the UW Patent Rights
and/or the UW Technology Rights for research, instructional, and/or other
academic purposes University has the right to use the UW Patent Rights and/or UW
Technology Rights for its own sponsored and collaborative research during the
term of this Agreement and to grant material transfer agreements to Third Party
non-profit

[***] 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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entities. University also has the right to publish any information included in
the UW Patent Rights and/or UW Technology Rights or any information that may
result from University's research in this area.

2.3 Federal Government Rights. Licensee acknowledges and understands that UW
Patent Rights may be the result of federal research funding and that such
funding imposes certain obligations on the University. Actions taken by
University to fulfill such obligations shall not be deemed inconsistent with
University's obligations under this Agreement. Licensee acknowledges that such
obligations under federal law include, without limitation, the following: a)
University's granting of a worldwide, non-exclusive, royalty-free license under
any UW Patent Rights by University to the United States government; and b) a
requirement that all United States patents and patent applications within the UW
Patent Rights include a statement of United States government patent rights.
Licensee acknowledges that any and all determinations of federal funding shall
be made solely by University and University's reasonable determination shall be
honored by Licensee. Licensee further acknowledges and agrees that, pursuant to
35 USC 200, the University's grant of an exclusive license to use or sell UW
Patent Rights in the United States are contingent on Licensee's agreement that
any products embodying UW Patent Rights or produced through the use of UW Patent
Rights must be manufactured substantially in the United States, unless Licensee
obtains a waiver from the appropriate federal agency.

3.0 SUBLICENSING

3.1 Right to Sublicense. During the term of this Agreement, Licensee shall have
the right to grant non-exclusive and exclusive Sublicenses to UW Patent Rights
and/or UW Technology Rights within the Field of Use and within the Licensed
Territory at royalty rates and with terms and conditions not less favorable to
University than those required of Licensee by this Agreement.

3.2 Sublicense Subject to this Agreement. Any and all proposed Sublicenses in
and to UW Patent Rights and/or UW Technology Rights granted by Licensee shall be
subject to prior approval of University, which shall not be unreasonably denied,
and shall be subject to the terms of this Agreement.

3.3 Copies to University. Licensee shall give the University written
notification and copies of any Sublicense it may grant under this Article 3.0.
Licensee agrees to provide such written notification indicating the effective
date of execution, effective period and operative provisions, within thirty (30)
days of its execution.. Such documents shall be held in confidence by the
University to the extent permitted by law or regulation.

3.4 Licensee agrees to consider in good faith any potential sublicensees that
University may suggest or recommend.

4.0 DELIVERY OF INFORMATION

4.1 UW Patent Rights. University agrees to disclose to Licensee copies of all
existing patents and patent applications comprising UW Patent Rights and
University shall continue

[***] 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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throughout the term of this Agreement to keep Licensee informed of all material
patent decisions and of all other patents and patent applications, pursuant to
Paragraph 9.1, that may later fall within the scope of UW Patent Rights.

4.2 Technical Information. University agrees to disclose to Licensee any
Technical Information that is in University's judgment reasonably necessary or
valuable to the commercial exploitation of the UW Patent Rights.

5.0 CONFIDENTIALITY

5.1 Confidentiality. Beginning on the Effective Date and continuing throughout
the term of this Agreement and thereafter for a period of three (3) years
("Confidentiality Period"), Licensee shall not disclose or otherwise make known
or available to any Third Party or Affiliate any Confidential Information,
without the express prior written consent of University. During the
Confidentiality Period, Licensee shall maintain the UW Patent Rights and UW
Technology Rights in confidence and refrain from disclosing information related
to UW Patent Rights or UW Technology Rights to a Third Party. In no event shall
Licensee incorporate or otherwise use UW Patent Rights or UW Technology Rights
in connection with any patent application filed by or on behalf of the Licensee.
Licensee agrees to restrict the use of UW Patent Rights and UW Technology Rights
exclusively to the terms of this Agreement. Licensee shall utilize reasonable
procedures to safeguard the Confidential Information. Licensee agrees that its
confidentiality obligations apply to Affiliates.

5.2 Public Records Act. The University of Washington is an agency of the state
of Washington and is subject to the Washington Public Records Act, RCW 42.17.250
et seq, and no obligation assumed by University under this Agreement shall be
deemed to be inconsistent with University's obligations defined under RCW 42.17.
In the event University receives a request for public records under the Public
Records Act for documents containing Confidential Information, and if University
concludes that the documents are not otherwise exempt from public disclosure,
University will provide Licensee notice of the request before releasing such
documents. Such notice shall be provided in a timely manner to afford Licensee
sufficient time to review such documents and/or seek a protective order, at
Licensee's expense. The responsibility for(1) protecting the Confidential
Information shall reside exclusively with Licensee utilizing the procedures
described in RCW 42.17.330.

6.0 DILIGENCE AND DEVELOPMENT MILESTONES

6.1 Development and Commercialization. During the term of this Agreement,
Licensee shall use, and shall compel its Sublicensee to use, at least the same
level of effort and diligence as Licensee uses or has used in proceeding with
its own product development, testing, manufacturing, sales and, where
applicable, initiating clinical trials and obtaining regulatory approval to
develop and commercialize at least one Licensed Product(s) or Combination
Product(s) Specifically, Licensee shall use such level of effort and diligence
in:

     6.1.1 developing Licensed Product(s) or Combination Product(s);

[***] 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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     6.1.2 filing for or seeking regulatory approvals in accordance with the
     business plan; and

     6.1.3 marketing and selling Licensed Product(s) or Combination Product(s)

6.2 Milestones. With regard to each of the Licensed Product(s) or Combination
Product(s), Licensee shall use at least the same level of effort and diligence
as Licensee uses or has used in proceeding with its own product development,
testing, manufacturing, sales and, where applicable, initiating clinical trials
and obtaining regulatory approval to meet all of the following diligence
milestones. Licensee agrees to provide, upon University's request, tangible
evidence of achieving the milestones.

     6.2.1 Assemble a scientific committee containing a multidisciplinary group
     of scientists (including, but not limited to, pathologists, microbiologists
     and cardiologists) for the design and oversight of a study that
     demonstrates the effective use of an antibacterial drug for the therapy of
     arterial chlamydia granuloma ("Study") by July 1st 2004.

     6.2.2 Initiate Study by September 30, 2004.

     6.2.3 Prepare and send to UW Researchers for review a pre-submission
     manuscript prepared by Licensee describing the outcomes of Study by
     December 31, 2005.

     6.2.4 First publication by Licensee or others in a peer reviewed
     international journal of Study by June 31, 2007.

     6.2.5 First publication by Licensee or others in a peer reviewed
     international journal of a study that demonstrates the effective use of an
     antibacterial drug for the therapy of acute or chronic coronary arterial
     chlamydia granuloma by December 31, 2009.

     6.2.6 First publication by Licensee or others in a peer reviewed
     international journal of a study conducted by a multidisciplinary group of
     scientists (including, but not limited to, pathologists, microbiologists
     and cardiologists) establishing that atherosclerosis is an arterial
     chlamydia granuloma or that chlamydia granuloma of the arteries is
     associated pathologically with atherosclerosis by December 31, 2006;

     6.2.7 Execute a strategic partnership and/or a Sublicense agreement for the
     development of Licensed Product(s) or Combination Product(s) with a Third
     Party by December 31, 2008.

     6.2.8 Filing by Licensee or Sublicensee of an NDA with the U.S. Food and
     Drug Administration for the use of antibacterial drugs to treat
     atherosclerosis and/or Chlamydia granuloma by December 31, 2010.

     6.2.9 Licensee or Sublicensee to apply for regulatory approval for Licensed
     Product(s) or Combination Product(s) from the U.S. Food and Drug
     Administration or a foreign equivalent governmental authority by December
     31, 2011.

[***] 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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     6.2.10 Licensee or Sublicensee to receive regulatory approval from the U.S.
     Food and Drug Administration or foreign equivalent governmental authorities
     for Licensed Product(s) or Combination Product(s) by December 31, 2012.

6.3 Milestone Payments. Licensee shall pay to University the following
non-creditable, non-cumulative, non-refundable fees within thirty (30) days of
the following milestones:

     6.3.1 [***] dollars ($[***] US) upon the second publication by Licensee or
     others in a peer reviewed international journal of a study establishing
     that atherosclerosis is an arterial Chlamydia granuloma and/or that
     Chlamydia granuloma of the arteries is the constant lesion associated
     pathologically with atherosclerosis;

     6.3.2 [***] dollars ($[***] US) upon Licensee's execution of a strategic
     partnership agreement and/or a Sublicense agreement for the development of
     antibacterial drugs for use in Chlamydia granuloma indications;

     6.3.3 [***] dollars ($[***] US) upon filing by Licensee, strategic partner
     or Sublicensee of an NDA with the U.S. Food and Drug Administration for the
     use of antibacterial drugs for treating Chlamydia granuloma

     6.3.4 [***] dollars ($[***] US) upon first commercial sale of Licensed
     Product(s) or Combination Product(s) anywhere in the Licensed Territory;
     and

     6.3.5 [***] dollars ($[***] US) after Licensee's or Sublicensee(s)'s gross
     revenues of Licensed Product(s) or Combination Product(s), reaches [***]
     Dollars [***] ($[***]) in any twelve (12)-month period

6.4 Pre-Commercialization Progress Reports. Until Licensee or any Sublicensees
engage in commercial use or sale of Licensed Product(s) or Combination
Product(s), Licensee shall prepare and submit to University within thirty (30)
days of December 31 of each year a report regarding the progress of Licensee and
any Sublicensee in developing the Licensed Product(s) or Combination Product(s)
for commercial exploitation. Such report shall include such particulars as are
necessary to demonstrate compliance with Licensee's diligence obligations set
forth in this Article 6.0

6.5 Failure to Meet Milestones. If Licensee fails to adhere to the diligence
requirements set forth in this Article 6.0 with respect to Licensed Product(s)
or Combination Product(s), University may terminate the license grants of this
Agreement with respect to such Licensed Product(s) or Combination Product(s) in
accordance with Article 18.0 (Term and Termination).

7.0 LICENSING FEES AND ROYALTIES

7.1 License Issue Fee. As partial consideration for the rights, privileges and
licenses granted hereunder, Licensee shall pay to University a one-time
non-refundable non-creditable license issue fee of [***] dollars ($[***] US) due
and payable according to the following schedule:

[***] 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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     -    [***] dollars (USD $[***] US) within fifteen (15) days of the
          Effective Date, and

     -    [***] dollars (USD $[***] US) within one hundred and eighty (180) days
          of the Effective Date.

7.2 License Maintenance Fee. Licensee shall pay to University [***] dollars
($[***] US) per year, creditable against milestone payments in the corresponding
year, until Licensee makes its first royalty payment. In years with more than
one milestone payment, the license maintenance fee will be waived for the
subsequent year. This license maintenance fee is due and payable at the end of
the quarter that includes the Effective Date of this Agreement.

7.3 Earned Royalty. Licensee shall pay to University an earned royalty of:

     7.3.1 [***] ([***]%) of Net Sales of Licensed Product(s), whether Licensed
     Product(s) is/are sold by Licensee or its Sublicensees; due and payable
     within thirty (30) days of the end of each calendar quarter during the term
     of this Agreement.

     7.3.2 Licensee shall pay earned royalties to University on a quarterly
     basis within thirty (30) days of each of the following dates: March 31,
     June 30, September 30, and December 31 of each year.

7.4 Earned Royalty for Combination Product(s). Where Combination Product(s)
is/are sold, Licensee shall pay an earned royalty based on the following
modification of Net Sales. When the component constituting a Licensed Product(s)
and each component not constituting a Licensed Product(s) have established
market prices in a particular country when sold separately, Net Sales in that
country shall be determined by multiplying the net sales for each such
Combination Product(s) by a fraction, the numerator of which shall be the
established market price for the Licensed Product(s) contained in the
Combination Product(s) and the denominator of which shall be the sum of the
established market price for the Licensed Product(s) plus the established market
price of the other components contained in the Combination Product(s). When such
separate market prices are not established in that particular country, the
Parties shall negotiate in good faith to determine a fair and equitable method
of calculating Net Sales in that country for the Combination Product(s) in
question.

7.5 Minimum Annual Royalties. Regardless of Net Sales, Licensee shall pay
minimum annual royalties to be creditable against earned royalties on a
non-cumulative basis and to be due in full and payable as shown below during the
term of this Agreement according to the following schedule:

     -    Due the first year in which a sale of Licensed Product occurs: [***]
          dollars ($[***] US)

     -    Due the first quarter of the every year thereafter: [***] dollars
          ($[***] US).

Nothing contained in this Paragraph 7.5 shall be construed to in any way alter
or reduce Licensee's obligations under Paragraph 7.3.

[***] 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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7.6 No Duplicative Royalties. Except as set forth in this Article 7.0, no
multiple royalties shall be payable to University where any Licensed Product(s)
or Combination Product(s), its manufacture, use, and/or sale is or will be
covered by more than one patent application or issued patent licensed under this
Agreement as part of UW Patent Rights.

7.7 Third Party Royalties. If Licensee is required to pay royalties to a Third
Party based on Licensee's manufacture, use, or sale of Licensed Product(s)
and/or Combination Product(s) subject to one or more patents of such Third
Party, the royalty rate specified in Paragraphs 7.3 and 7.4 shall be reduced by
an equitable amount to be determined through good faith negotiations between
University and Licensee, provided that use of any Third Party patent is required
in connection with such manufacture, use, or sale of Licensed Product(s) and/or
Combination Product(s), and provided that the royalty to University shall not
fall below fifty percent (50%) of that otherwise payable under this Agreement.

7.8 Currency and Exchange Rate. All payments required under this Agreement shall
be made in United States dollars by check, money order or wire transfer to a
bank account as designated by University. All such payments must include the
University invoice number or the contract number [***] on the check or cover
letter. The royalties on sales in currencies other than United States dollars
shall be calculated using the appropriate foreign exchange rate for such
currency as published in The Wall Street Journal (Western edition) on the last
business day of each calendar quarter in which the sales occurred. All non-U.S.
taxes related to royalty payments shall be paid by Licensee and are not
deductible from the payments due University.

7.9 Wire Transfers. If payment is made by wire transfer, such wire transfer must
contain the following information: [***], Office of Technology Licensing, ATTN:
Financial Manager. The wire transfer should be directed towards [***], ABA#
[***], and University budget number ([***]) Bank of America, University Branch,
4701 University Way NE, Seattle, WA 98105-4412, and a copy must be sent via fax
to University OTL Financial Manager and a copy to University OTL Technology
Manager at 206-685-4767. International wires must be paid in United States
dollars and must also include the reference "[***]". In the case of payment made
by wire transfer to fulfill any financial obligation of Licensee under this
Agreement any and all requirements of Article 7 must be met.

7.10 Late Fee. Licensee agrees to pay a late fee for any overdue (i.e., more
than thirty (30) days past due) licensing fee, royalty payment or other payment
due to University under terms of this Agreement. The late fee shall be computed
as the United States prime rate plus two percent (2%), compounded monthly, as
set forth by The Wall Street Journal (Western edition) on the date on which such
payment is due, of the outstanding, unpaid balance. The payment of such a late
fee shall not foreclose or limit University from exercising any other rights it
may have as a consequence of the lateness of any payment.

8.0  SUBLICENSING PAYMENTS AND FEES.

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8.1 Sublicense Fees. Within sixty (60) days after the end of each Semi-Annual
Period during the term of this Agreement, Licensee shall pay to University an
amount based on any Sublicensing Consideration received by Licensee during such
Semi-Annual Period as follows:

     8.1.1 [***] of any Sublicensing Consideration received from any
     Sublicensee for the grant of a Sublicense of UW Patent Rights and/or UW
     Technology Rights if the Sublicense is executed before publication by
     Licensee or others in a peer reviewed journal of a study that demonstrates
     the effective use of an antibacterial drug for the therapy of arterial
     Chlamydia granuloma; or

     8.1.2 [***] of any Sublicensing Consideration received from any Sublicensee
     for the grant of a Sublicense of UW Patent Rights and/or UW Technology
     Rights if the Sublicense is executed after a first sale of the Licensed
     Product(s) or Combination Product(s) by Licensee.

8.2  Equity.

     8.2.1 Publicly Traded Equity. If Licensee receives consideration in the
     form of publicly traded equity from a Sublicense, all provisions of Article
     8.0 (Sublicensing Payments and Fees) shall apply, except that University
     may, at its sole discretion, elect to receive University's share of such
     equity as either equity or the Fair Market Cash Value (hereinafter defined)
     equivalent of such equity at the time of issuance to Licensee. "Fair Market
     Cash Value" means the average price that the stock in question is publicly
     trading at for twenty (20) days prior to the transfer of the equity to
     Licensee or Affiliate from the Sublicensee.

     8.2.2 Non-publicly Traded Equity. If Licensee receives consideration in the
     form of equity that is not publicly traded from a Sublicense, all
     provisions of Article 8.0 (Sublicensing Payments and Fees) shall apply
     University shall have the right to sell such equity at any time after a
     public or private market for such equity is created.

     8.2.3 If under the provisions of this Paragraph 8.2 University elects to
     receive the equity, such equity shall be in the name "University of
     Washington".

     8.2.4 Notwithstanding the above, it is understood and agreed that
     University shall not be entitled to any portion of amounts received by
     Licensee from Sublicensee(s) for the purchase of equity in Licensee, debt
     financing, research and development, the license or Sublicense(s) of any
     intellectual property other than the UW Patent Rights and/or UW Technology
     Rights, or reimbursement for patent or other expenses.

9.0  PATENT PROSECUTION AND COST RECOVERY.

9.1 University Control of Prosecution. Subject to Paragraph 18.6 University, or
its designees shall have exclusive control over the filing, prosecution and
maintenance of any and all patent applications included in UW Patent Rights,
whether pending or not yet filed as of the Effective

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Date of this Agreement, and of the maintenance and other management of any and
all issued patents included in UW Patent Rights during the term of this
Agreement.

9.2 Licensee Role in Prosecution. University shall keep Licensee informed of the
status of any and all new patents and/or patent applications that are part of UW
Patent Rights Licensee may provide comments to University on courses of action
with respect to the filing of new patent applications relating to UW Patent
Rights, prosecution of patent applications within UW Patent Rights, and/or
maintenance of patents within UW Patent Rights, provided University has
exclusive authority to prosecute and maintain UW Patent Rights.

9.3 University Cost Recovery from Licensee. Licensee agrees to reimburse
University for all fees and costs for those actions related to the filing,
prosecution and maintenance of patent applications, including, without
limitation, interference, oppositions, and reexaminations, and maintenance and
defense of patents, in UW Patent Rights, whether incurred prior to the execution
of this Agreement or during the term of this Agreement. Such fees and costs
shall not include costs incurred by the University in the use of its own
resources, such as employee time Licensee agrees to pay invoices for such fees
and costs submitted by University upon receipt of any such invoices. In any case
where Licensee fails to pay fees and costs invoiced to Licensee by University
within sixty (60) days of the date of such invoice, University may file,
prosecute and/or maintain a patent application or patent at its own expense and
for its own exclusive benefit. Licensee shall thereupon forfeit any license
related to the filing, prosecution, and maintenance of patent applications under
such patent or patent application.

     9.3.1 University Cost Recovery from Licensee for Past Costs. Licensee is
     hereby required to pay no later than June 13, 2003 the sum of Twenty
     Thousand Four Hundred Twenty Four Dollars and Fifty One Cents ($20,424.51
     US) to cover the past fees and costs as described above in Paragraph 9.3

     9.3.2 University Cost Recovery from Licensee for Future Costs. Licensee is
     hereby required to pay within thirty (30) days of the Effective Date the
     sum of One Thousand Seven Hundred Sixty Five dollars ($1,765.00) ("Advanced
     Payment") to cover the future fees and costs as described above in
     Paragraph 9.3. The Advanced Payment will be placed in a non-interest
     bearing account to be deposited in a University Advanced Payment account
     University will submit the following documents to Licensee on a quarterly
     basis: 1) an invoice which will summarize all costs and fees that have been
     paid by University in support of the UW Patent Rights for the immediately
     preceding quarter; 2) copies of all legal invoices paid by the University
     during the immediately preceding quarter; and 3) either a report
     identifying any unused portion of the Advanced Payment to be applied to the
     next quarter's fees and costs or, if the Advanced Payment has been
     depleted, a request for additional funds to replenish the Advanced Payment
     account. The determination of the amount of additional funds necessary for
     the Advanced Payment account will be made solely by the University and will
     be based on the patent attorney's estimate for the upcoming year's fees and
     costs. Upon termination of this Agreement, any unexpended balance of the
     Advanced Payment will be held by University to pay outstanding fees and
     costs as described in Paragraph 9.3, and the unused portion refunded to
     Licensee within ninety (90) days after University's final accounting
     University may, at University's sole discretion, apply any such unused

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     portion of the Advanced Payment toward the payment of other monies Licensee
     owes University under this Agreement. The Parties agree that in
     establishing the Advance Payment account no fiduciary relationship between
     them is created, and that University's duties with regard to the Advance
     Payment are limited to those explicitly stated herein.

10.0 REPORTS

10.1 Quarterly Report. With each payment to University, Licensee shall include a
report setting forth the relevant details of the business conducted by Licensee
and each Sublicensee, if applicable, during the preceding calendar quarter
pursuant to their obligations under Paragraph 7.3 of this Agreement. This
report, for Licensee and each Sublicensee, shall include, at a minimum, the
following:

     10.1.1 the number of units of Licensed Product(s) and Combination
     Product(s) manufactured, used, or sold and by country within the Licensed
     Territory;

     10.1.2 the gross amounts invoiced for Licensed Product(s) and Combination
     Product(s);

     10.1.3 any and all discounts or allowances, and description of same,
     granted to Third Parties; and

     10.1.4 the calculation of total amounts due University

11.0 RECORD KEEPING

11.1 Records Retained. Licensee shall keep complete and accurate records and
books of account containing all information necessary for the computation and
verification of the amounts to be paid hereunder. Licensee shall keep these
records and books for a period of five (5) years, or longer if required by law,
following the end of the accounting period to which the information pertains.

11.2 Auditing Rights. Licensee agrees, at the request of University, to permit
one or more accountants selected exclusively by the University ("Accountants")
to have access to Licensee's records and books of account pertaining to this
Agreement during ordinary working hours to audit with respect to any payment
period ending prior to such request, the correctness of any report or payment
made under this Agreement, or to obtain information as to the payments due for
any such period in the case of failure of Licensee to report or make payment
pursuant to the terms of this Agreement.

11.3 Scope of Disclosure. The Accountant shall not disclose to University any
information relating to the business of Licensee except that which is necessary
to inform University of:

     11.3.1 the accuracy or inaccuracy of Licensee's reports and payments;

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     11.3.2 compliance or noncompliance by Licensee with the terms and
     conditions of this Agreement; and

     11.3.3 the extent of any inaccuracy or noncompliance.

11.4 Accountant Copies. Should the Accountant believe there is an inaccuracy in
any of Licensee's payments or noncompliance by Licensee with any of such terms
and conditions, the Accountant shall have the right to make and retain copies
(including photocopies) of any pertinent portions of the records and books of
account.

11.5 Costs of Audit. In the event that Licensee's royalties calculated for any
quarterly period are under reported by more than three percent (3%), the costs
of any audit and review initiated by University will be borne by Licensee;
otherwise, University shall bear the costs of any audit initiated by University.

12.0 PATENT INFRINGEMENT

12.1 Mutual Notice. Each Party shall promptly inform the other Party of any
alleged infringement of UW Patent Rights by a Third Party of which it becomes
aware, and provide to the other Party with any available evidence thereof

12.2 Licensee First Right to Settle During Term of Exclusivity. During the term
of exclusivity of the license granted hereunder, Licensee shall have the first
right to respond to, defend, and prosecute in its own name actions or suits
relating to UW Patent Rights. Licensee shall not settle any suits or actions in
any manner relating to the UW Patent Rights, however, where the settlement
adversely and materially affects the validity, enforceability, or existence of
UW Patent Rights without obtaining the prior written consent of University,
which consent shall not be unreasonably withheld or delayed. To enjoy said first
right, Licensee must initiate bona fide action to respond to any alleged
infringement within ninety (90) days of learning of said infringement. In the
event that University consents to settlement by Licensee, the proceeds from such
settlement will be distributed as follows: after Licensee has recovered its
reasonable attorneys' fees and other out-of-pocket expenses directly related to
any action, suit, or settlement for infringement of UW Patent Rights in the
Field of Use, University and Licensee shall divide any remaining damages,
awards, or settlement proceeds in the following manner:

University:   Twenty Percent (20%)
Licensee:     Eighty Percent (80%)

Any payment by an alleged infringer that constitutes consideration for Net
Sales, however, shall be handled according to the payment provisions of Article
7.0 (Licensing Fees and Royalties). Any payment by an alleged infringer that
constitutes consideration for the grant of a Sublicense, however, shall be
handled according to the applicable payment provisions for Sublicenses set forth
in this Agreement.

12.3 Voluntary Participation by University. In the event Licensee institutes
suit against an alleged infringer during the term of exclusivity as provided in
this Agreement, then University

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may agree to voluntarily participate as a named party at its sole discretion. If
University decides not to voluntarily participate in such suit, then University
agrees to be bound by any final judgment rendered by the court. Further, if
University chooses not to voluntarily participate but the court determines
University is a necessary or indispensable party, then Licensee agrees to pay
all University's reasonable attorneys' fees and other out-of-pocket direct
associated expenses, and University agrees to make reasonable efforts to
cooperate and assist Licensee in connection with the suit.

12.4 University Right to Institute Action. If Licensee fails, within ninety (90)
days of learning of an alleged infringement, to secure cessation of the
infringement, institute suit against the infringer, or provide to University
satisfactory evidence that Licensee is engaged in bona fide negotiation for the
acceptance by infringer of a Sublicense in and to relevant patents in UW Patent
Rights for the Field of Use, University may then, upon written notice to
Licensee, assume full right and responsibility to secure cessation of the
infringement, institute suit against the infringer, or secure acceptance of a
Sublicense from Licensee in and to relevant patents in UW Patent Rights,
approval for which Sublicense Licensee shall not unreasonably withhold. If
University in accordance with the terms and conditions of this Agreement chooses
to institute suit against an alleged infringer, University may bring such suit
in its own name (or, if required by law, in its and Licensee's name) and at its
own expense, and Licensee shall, but at University's expense for Licensee's
direct associated expenses, fully and promptly cooperate and assist University
in connection with any such suit. Any and all damages, awards, or settlement
proceeds arising from such a University initiated action shall be University's.

12.5 No Obligation to Institute Action. Neither Licensee nor University is
obligated under this Agreement to institute a suit against an alleged infringer
of UW Patent Rights.

13.0 PATENT VALIDITY

13.1 Licensee Notice to University of Third Party Actions. If any claim
challenging the validity or enforceability of any of the UW Patent Rights shall
be brought against Licensee, Licensee shall promptly notify University.
University, at its sole discretion, shall have the right, within thirty (30)
days after notification by Licensee of such action, to intervene and take over
the sole defense of the claim at University's expense. If University opts not to
intervene and take over the sole defense of the claim within thirty (30) days
after notification by Licensee, Licensee shall have the right to control the
defense of the claim at its own expense.

13.2 Covenant Not to Challenge UW Patent Rights. Licensee agrees during the term
of this Agreement not to challenge the validity or enforceability of any of the
UW Patent Rights.

14.0 PATENT MARKING. Licensee shall mark any and all material forms of Licensed
Product(s), Combination Product(s) or packaging pertaining thereto made and sold
by Licensee in the United States with an appropriate patent marking identifying
the pendency of any US patent application and/or any issued U.S. or foreign
patent forming any part of the UW Patent Rights. All product(s) shipped or sold
in other countries shall be marked in such a manner as to provide

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notice to potential infringers pursuant to the patent law and practice of the
country of manufacture or sale.

15.0 USE OF NAMES. Nothing contained in this Agreement shall be construed as
conferring any right to use in advertising, publicity or other promotional
activities any name, trade name, trademark, or other designation of University
without the express written permission of University, unless such listing is
required under local laws or regulations, provided that Licensee may state the
existence of this Agreement and the fact that both Parties entered into it For
any use other than the foregoing, Licensee hereby expressly agrees not to use
the name "University of Washington" or any contraction, abbreviation, or
simulation thereof without prior written approval from an authorized
representative of University If University or Licensee wishes to issue a press
release or make any other public announcement relating to the Agreement, the
Parties will consult with one another in advance on the content to ensure the
medical and scientific accuracy of the announcement and to ensure that such
press release or other public announcement does not contain Confidential
Information. In any event, no press release or other public announcement shall
be issued without the express written authorization of the Parties, and the
Parties agree to expedite the approval of each other's press releases

16.0 REPRESENTATIONS AND WARRANTIES

16.1 Right to Grant License. University represents and warrants that it has the
right to grant the license in and to the UW Patent Rights and disclose the UW
Technology Rights set forth in this Agreement.

16.2 DISCLAIMER OF WARRANTY. UNIVERSITY EXPRESSLY DISCLAIMS ANY AND ALL
WARRANTIES, WHETHER EXPRESS OR IMPLIED, PERTAINING TO THE MERCHANTABILITY OR
FITNESS FOR A PARTICULAR PURPOSE OF THE UW PATENT RIGHTS, UW TECHNOLOGY RIGHTS,
LICENSED PRODUCT(S), OR ANYTHING ELSE LICENSED, DISCLOSED, OR OTHERWISE PROVIDED
TO LICENSEE UNDER THIS AGREEMENT

Nothing in this Agreement shall be construed as:

     16.2.1 A representation or warranty by University as to the patentability,
     validity, scope, or usefulness of the UW Patent Rights; or

     16.2.2 A representation or warranty by University that anything made, used,
     sold, or otherwise disposed of under any license granted in this Agreement
     is or will be free from infringement of patents or other proprietary rights
     not included in the UW Patent Rights

16.3 LIMITATION OF LIABILITY OF UNIVERSITY. UNIVERSITY'S MAXIMUM LIABILITY UNDER
THIS AGREEMENT IS LIMITED TO THE COSTS AND FEES PAID TO UNIVERSITY UNDER THIS
AGREEMENT. UNIVERSITY WILL NOT BE LIABLE DIRECTLY OR INDIRECTLY FOR ANY PROPERTY
DAMAGE, PERSONAL INJURY

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LOSS OF USE, INTERRUPTION OF BUSINESS, LOSS OF PROFITS, OR OTHER SPECIAL,
INCIDENTAL OR CONSEQUENTIAL DAMAGES, HOWEVER CAUSED, WHETHER FOR BREACH OF
WARRANTY, CONTRACT, TORT (INCLUDING NEGLIGENCE), STRICT LIABILITY OR OTHERWISE

16.4 Representations by Licensee, Licensee represents that it has the right and
authority to enter into this Agreement and that it has listed all Affiliates as
of the Effective Date in Exhibit 1.2

17.0 INDEMNIFICATION AND INSURANCE

17.1 Licensee Indemnification of University. Licensee agrees to indemnify, hold
harmless, and defend University, its regents, officers, inventors, employees,
students, and agents ("Indemnified Parties") against any and all claims, causes
of action, lawsuits, or other proceedings ("Claims") and losses, damages, costs,
fees, and expenses ("Costs") filed, instituted, resulting from, or arising out
of the design, process, manufacture, use, possession, or operation by any person
or party (including Sublicensees) of UW Patent Rights, UW Technology Rights, any
products based on or incorporating UW Patent Rights or UW Technology Rights, or
any other embodiment of UW Patent Rights or UW Technology Rights Licensee agrees
to such indemnification even though such Claims or Costs related thereto are
based upon doctrines of strict liability or product liability Such indemnity
shall not, however, apply to Claims arising from the gross negligence or
intentional misconduct of any Indemnified Party This indemnification clause
shall survive the termination of this Agreement

17.2 Licensee Liability Insurance. Licensee shall maintain general liability
insurance including, but not limited to, product liability and contractual
liability coverage at an amount customary to Licensee's business for activities
and/or products of a similar nature that shall be in effect no later than the
date of the first human clinical testing of Licensed Product(s) and/or Combined
Product(s), Licensee's general liability insurance shall name University as an
additional insured Licensee shall declare whether the insurance is provided on a
"claims-made" form and must notify University within three (3) business days if
coverage is canceled

17.3 Human Clinical Trials. Licensee shall provide to University within thirty
(30) days prior to the initiation of human clinical trials with respect to
Licensed Product(s), certificates evidencing the existence and amount of the
insurance required under Article 18.0 (Term and Termination). Licensee shall
issue irrevocable instructions to its insurance agent and to the issuing
insurance company to notify University of any discontinuance or lapse of such
insurance not less than thirty (30) days prior to the time that any such
discontinuance is due to become effective Licensee shall provide University a
copy of such instructions upon their transmittal to the insurance agent and
issuing insurance company Licensee shall further provide University, at least
semi-annually, proof of continued coverage

18.0 TERM AND TERMINATION

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18.1 Term. The term of this Agreement shall commence on the Effective Date and
shall continue until the last of UW Patent Rights expires, unless sooner
terminated in accordance with the provisions set forth under this Article 18.0.

18.2 Material Breach By Licensee. University may terminate this Agreement
effective upon thirty (30) days prior written notice of termination to Licensee,
if Licensee materially breaches this Agreement and does not cure such breach
within sixty (60) days after receiving such notice. Licensee agrees that any and
all commercialization diligence requirements and required payments are material
license terms according to Articles 6.0 (Diligence and Development Milestones),
7.0 (Licensing Fees and Royalties), 8.0 (Sublicensing Payments and Fees) and 9.0
(Patent Prosecution and Cost Recovery). In the event that Licensee has breached
any such obligation with respect to Licensed Product(s) or Combination
Product(s), the University may, in its sole discretion, terminate the license
granted herein with respect to the UW Patent Rights and/or UW Technology Rights
relating to such Licensed Product(s) or Combination Product(s), while retaining
the remainder of this Agreement in full force and effect.

18.3 At-Will Termination By Licensee. Licensee may terminate this Agreement
effective upon sixty (60) days prior written notice if in Licensee's reasonable
opinion it will not commercialize the UW Patent Rights.

18.4 Insolvency. This Agreement, and the license granted to Licensee hereunder,
shall terminate immediately in the event that:

     18.4.1 Licensee seeks liquidation, reorganization, dissolution or is
     insolvent or evidence exists as to its insolvency or winding up of itself,
     or makes any general assignment for the benefit of its creditors;

     18.4.2 a petition is filed by or against Licensee, or any proceeding
     against Licensee as a debtor, under any bankruptcy or insolvency law,
     unless the laws then in effect void the effectiveness of this provision;

     18.4.3 a receiver, trustee, or any similar officer, under bankruptcy law,
     is appointed to take possession, custody or control of all or part of
     Licensee's assets or property; or

     18.4.4 Licensee adopts any resolution of its Board of Directors or
     stockholders for the purpose of effecting any of the foregoing

18.5 No Further Rights. Upon termination, Licensee shall have no further rights
under either the UW Patent Rights or the UW Technology Rights

18.6 Financial Obligations. Termination by University or Licensee under the
options set forth in this Agreement shall not relieve Licensee from any
financial obligation to University accruing prior to termination or from
performing according to any and all other provisions of this Agreement that
survive termination

18.7 Other Remedies. The provisions under which this Agreement may be terminated
shall be in addition to any and all other legal remedies which either Party may
have for the enforcement

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of any and all terms hereof, and do not in any way limit any other legal remedy
such Party may have

19.0 ASSIGNMENT

19.1 University Consent Required. This Agreement may not be assigned by Licensee
without the express written consent of University except that Licensee may
assign or otherwise transfer this Agreement and the license granted hereby and
the rights acquired by it hereunder so long as such assignment or transfer shall
be accompanied by a sale or other transfer of Licensee's entire business or of
the entirety of that part of Licensee's business to which the license granted
hereby relates, including a change of control Licensee shall give University
thirty (30) days prior notice of such assignment and transfer. Upon such
assignment or transfer, the term "Licensee" as used in this Agreement shall
include such assignee or transferee and this Agreement shall be binding upon
Licensee's permitted successors and assigns

19.2 University Assignment. University may assign or otherwise transfer this
Agreement and the license granted hereby and the rights acquired by it
hereunder. University shall give Licensee thirty (30) days prior notice of such
assignment and transfer. Upon such assignment or transfer by such assignee or
transferee, the term University herein shall include such assignee or transferee
and this Agreement shall be binding upon University's permitted successors and
assigns.

20.0 NOTICE OR DEMAND

20.1 Written Notice Required. All notices, requests, and other communications
required or permitted under this Agreement shall be in writing, shall refer
specifically to this Agreement and the OTL # 1168-1291129DL, and shall be deemed
delivered upon receipt. If delivered by United States mail, postage should be
prepaid by certified return receipt. If sent by facsimile (provided that a
transmittal sheet indicates confirmation), or other electronic transmission, a
confirmation copy will be forwarded. Any such notices, requests, and other
communications shall be addressed as follows:

LICENSEE:     ActivBiotics, Inc.
              128 Spring Street
              Lexington, MA
              Attn : Chalom Sayada, MD Ph.D.
              Chief Executive Officer, ActivBiotics Inc
              Main: 781-372-4800
              Direct: 781-372-4806
              Fax: 781-274-8638

UNIVERSITY:   University of Washington
              Office of Technology Licensing
              Attn: Director
              4311 11th Avenue NE, Suite 500

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              Seattle, WA 98105
              Fax: 206-685-4767

20.2 Change of Address. Either Party, by notice, may change the address to which
notice will be sent and unless so notified of a change of address all notices
mailed to Licensee or University at the above stated address will be deemed
sufficient

21.0 EXPORT CONTROLS. Licensee acknowledges and agrees that University is
subject to United States laws and regulations controlling the export of
technical data, computer software, laboratory prototypes, and other commodities
(including without limitation the Arms Export Control Act, the Export
Administration Act of 1979 and the U.S., Patriot Act, and including all
amendments thereof), and that its obligations hereunder are contingent on
compliance with applicable United States export laws and regulations. The
transfer of certain technical data and commodities may require a valid export
license from the cognizant agency of the United States Government and/or written
assurances by Licensee that Licensee shall not export data or commodities to
certain foreign countries without prior approval of such agency University does
not represent that an export license shall be required, nor does it represent
that such an export license shall be issued Licensee hereby agrees that Licensee
shall not export or re-export, directly or indirectly, any Licensed Product(s)
and/or UW Patent Rights and/or UW Technology Rights to any country for which the
United States Government or other competent authority at the time of export
requires an export license or other approval, without first obtaining such
license or approval from the appropriate governmental authority; obtaining such
permission will be the sole responsibility of Licensee

22.0 DISPUTE RESOLUTION. The Parties shall attempt to resolve through good faith
discussions any dispute, which arises under this Agreement. Any dispute may, at
the election of either Party, be referred to the Licensee's Chief Executive
Officer and University's Director of Technology Licensing, or their authorized
representatives

23.0 ATTORNEYS' FEES. The substantially prevailing party in arbitration or in
any judicial or administrative action or proceeding arising under or in
connection with this Agreement shall be entitled to reimbursement from the other
party for its reasonable costs and attorneys' fees, including those on appeal,
and including without limitation, the cost at the hourly charges routinely
charged by the person providing the services, the time of legal assistants,
secretarial and clerical overtime, and fees and expenses of experts retained by
counsel

24.0 PROPRIETARY RIGHTS. Licensee will not, by performance under this Agreement,
obtain any ownership interest in the UW Patent Rights and/or UW Technology
Rights or any other proprietary rights or information of University, its
officers, inventors, employees, students, or agents.

25.0 SEVERABILITY. If any provision of this Agreement is determined to be
unenforceable or otherwise unlawful, then such provision will be without effect,
and the remaining terms and conditions of this Agreement will survive, as if
such provision had not been included herein. The

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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

                                       20

<Page>

Parties will promptly meet to agree upon further terms which will, within the
confines of the law, most substantially satisfy the intention of the Parties as
reflected by the ineffective provision

26.0 HEADINGS AND CAPTIONS. The headings and captions of the Articles of this
Agreement are for convenience of reference only and in no way define, limit or
affect the scope or substance of any Article of this Agreement

27.0 SURVIVAL. Article 17.0 (Indemnification and Insurance), Article 23.0
(Attorneys' Fees), and Paragraph 28.1 (Choice of Law/Venue), and other
provisions that by their context would survive, shall survive the termination of
this Agreement.

28.0 MISCELLANEOUS

28.1 Choice of Law/Venue. Because University is a public institution with its
central administrative offices in Seattle, Washington, and because of the
critical role played by University in administrating terms of this Agreement,
the Parties agree this Agreement shall be governed by and interpreted in
accordance with the laws of the state of Washington, regardless of its conflict
of law provisions. The Parties further agree that any claim related in any
manner to the Agreement shall be instituted and commenced in, and venue shall be
either King County, Washington or the United Stated District Court for the
Western District of Washington

28.2 Successors and Assigns. This Agreement shall be binding upon and inure to
the benefit of both Parties and their respective successors and assigns,
including any corporation or entity with which or into which either Party may be
merged or which may succeed to its assets or business

28.3 Non-Agency. With respect to the subject matter of this Agreement, Licensee
and University are independent contractors and neither shall be deemed to be an
agent, employee, partner, nor joint-venturer of the other for any purpose

28.4 Waiver. No delay or omission by either Party in exercising any right under
this Agreement shall operate as a waiver of that or any other right. A waiver or
consent given by either Party on any one occasion is effective only in that
instance and shall not be construed as a bar to or waiver of any right on any
other occasion

28.5 Entire Agreement. The Parties hereto acknowledge that this Agreement,
together with the Exclusive Option Agreement Between ActivBiotics, Inc. and the
University of Washington, dated June 13, 2002, sets forth the entire Agreement
and understanding of the Parties hereto as to the subject matter hereof,
supersedes any and all prior written and oral agreements, understandings or
offers. This Agreement shall be operative in the event of inconsistencies with
any other agreement. This Agreement may not be modified, changed or discharged
in whole or in part, except by an agreement in writing signed by authorized
representatives of both Licensee and University

IN WITNESS WHEREOF, THE PARTIES HAVE EACH READ AND BY SIGNATURE OF THIS
AGREEMENT AGREE TO BE LEGALLY BOUND BY ALL OF THE ATTACHED

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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

                                       21

<Page>

TERMS AND CONDITIONS, ALL OF WHICH ARE INCORPORATED FULLY INTO THIS AGREEMENT,
AND HAVE CAUSED THIS AGREEMENT TO BE EXECUTED BY THEIR DULY AUTHORIZED
REPRESENTATIVES.

ACTIVBIOTICS INC.                       UNIVERSITY OF WASHINGTON

By: /s/ Chalom B. Sayada                By: /s/ James A. Severson
    ---------------------------------       ------------------------------------

Name: Chalom B. Sayada, M.D., Ph.D.     Name: James A. Severson

Title: CEO                              Title: Vice Provost, Intellectual
                                               Property and Technology Transfer

Date: June 2, 2003                      Date: May 19, 2003

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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

                                       22

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                                    EXHIBIT A

          Exclusive Option Agreement Between ActivBiotics, Inc. and the
                            University of Washington

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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

                                       23

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                           EXCLUSIVE OPTION AGREEMENT

                                     BETWEEN

               ACTIVBIOTICS, INC. AND THE UNIVERSITY OF WASHINGTON

THIS EXCLUSIVE OPTION AGREEMENT ("Agreement") is entered into on June 13th, 2002
("Effective Date") by and between ActivBiotics, Inc., a Delaware corporation
with its principal place of business at Broadway Street 198, Cambridge, MA
02139 ("Company") and the University of Washington, a public institution of
higher education and an agency of the state of Washington acting through its
Office of Technology Licensing, with administrative offices at 1107 NE 45th
Street, Suite 200, Seattle, WA 98105 ("University").

1. Recitals.

1.1 Whereas, University has developed and owns or is in possession of certain
technology ("UW Technology" defined below) relating to Diagnosis and Treatment
of Arterial Chlamydial Granuloma;

1.2 Whereas, Company is an early stage pharmaceutical company focusing on the
development of cures for chronic and infectious diseases;

1.3 Whereas, Company is willing to support the preparation, filing, prosecution
and maintenance of certain patent applications or issued patents covering all or
part of UW Technology and is willing to devote corporate resources directed
towards the support and development of UW Technology;

1.4 Whereas, University is willing to grant Company an option to obtain an
exclusive, worldwide, royalty bearing license to UW Patent Rights in the Field
of Use under the terms and conditions of this Agreement;

Now, therefore, in consideration of the mutual promises set forth herein, and
other good and valuable consideration, the receipt and sufficiency of which is
hereby expressly acknowledged, the University and Company (collectively "the
Parties") hereby agree as follows:

2. Definitions.

2.1 "UW Technology" shall mean technology related to Diagnosis and Treatment of
Arterial Chlamydial Granuloma as developed in the University laboratory by Dr(s)
Cho Cho Kuo, Allan Shor, Dorothy L. Patton, Lee Ann Campbell and I Thomas
Grayston and as recorded in OTL file # 1169-1291129DL

2.2 "UW Inventors" shall mean Drs Cho Chuo Kuo and Dr Allan Shor.

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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

                                                                UW-ActiveBiotics
                                                              OTL#1169-1291129DL
                                                                       6/13/2002

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2.3 "UW Patent Rights" shall mean the United States Patents listed below and any
corresponding US patent issued therefrom, including all reissues, divisionals,
continuations, reexaminations and extensions thereof, together with all
corresponding foreign patents, extensions, supplemental protection certificates
and applications corresponding thereto now issued or issued during the term of
the license agreement and which directly relate to UW Technology. A patent or
patent application shall cease to be a UW Patent Right when any of the following
occur: a) it expires; b) it is abandoned; or c) it is held to be unenforceable
by a court of competent jurisdiction from which no appeal can be taken. Issued
patents as of the Effective Date are:

United States Patent Number:     US6,043,225
Title:                           Diagnosis and Treatment of Arterial Chlamydial
                                 Granuloma
Application Date:                3/28/2000
Assignee:                        University of Washington and Allan Shor*

United States Patent Number:     US5,830,874
Title:                           Diagnosis and Treatment of Arterial Chlamydial
                                 Granuloma
Application Date:                11/3/1998
Assignee:                        University of Washington and Allan Shor*

United States Patent Number:     US5,424,187
Title:                           Diagnosis and Treatment of Arterial Chlamydial
                                 Granuloma
Application Date:                6/13/1995
Assignee:                        University of Washington and Allan Shor*

*    Exclusively controlled by University of Washington under separate agreement
     with Shor evidence of which is given in Appendix B.

2.4 "Technical Information" shall mean any technical facts, data, or advice,
written or oral (in the form of information contained in patents and patent
applications, reports, letters, drawings, specifications, testing procedures,
training and operational manuals, bills of materials, photographs and other
materials) directly related to UW Technology and which is owned or in the
possession of University, delivered to Company by University and not subject to
third party rights.

2.5 "Field of Use" shall mean Diagnosis and Treatment of Arterial Chlamydial
Granuloma, which includes related arterial and coronary diseases or disorders
caused or influenced by chlamydial infections.

3. Grant of Option, Exercise of Option, and Option Period.

3.1 Grant. Provided that Company complies with obligations set forth under this
Agreement, University hereby grants to Company a time-limited option to
negotiate a royalty-bearing,

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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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                                                              OTL#1169-1291129DL
                                                                       6/13/2002

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limited-term, worldwide exclusive license on commercially reasonable terms under
the UW Patent Rights in the Field of Use to make, have made, use, sell, and
offer to sell products that use or are derived from the UW Patent Rights in the
Field of Use.

     3.1.1 The option granted above, and any license granted pursuant thereto,
is subject to a reserved right by the University, with the right to
non-exclusively sublicense to non-profit institutions, to make, have made, and
use products, processes, or other subject matter covered by the UW Patent
Rights, UW Technology or Technical Information for internal research,
instructional and/or other academic purposes. University shall have the right to
use the UW Patent Rights, UW Technology or Technical Information for its own
internal, research, including sponsored research and academic collaborations
during the term of this Agreement. University shall also have the right to
publish any information included in the UW Patent Rights, UW Technology or
Technical Information or any information that may result from their research in
this area.

     3.1.2 Article 3.1 notwithstanding, Company acknowledges that UW Patent
Rights involve federal research funding. Company acknowledges that University
has obligations ("Obligations") under federal law, and actions taken by
University to fulfill such obligations shall not be deemed inconsistent with
University's obligations under this Agreement nor any license agreement granted
pursuant thereto. Company acknowledges that Obligations include, without
limitation, the granting of a worldwide non-exclusive, royalty-free license for
any such UW Patent Rights, by University to the United States Government, and a
statement of United States Government patent rights on all the patents and
patent applications within the UW Patent Rights. Company acknowledges that any
and all determinations of federal funding involvement shall be made solely by
University and University's determination shall be honored by Company.

3.2 Option Period/Option Period Extension. The option shall expire on the
earlier of either (a) execution of a license or (b) 1 year from the Effective
Date of the Agreement. If at the one (1) year anniversary of the Effective
Date of the Agreement the option has not been exercised, the Company shall
have the right to extend the option period ("Option Period Extension") for a
fee of [***] dollars ([***]USD) for an additional year. The Option Period
Extension shall expire the earlier of either (a) execution of a license or
(b) one (1) years from the Effective Date of the extension.

3.3 Commercialization Prohibited During the term of this Agreement. Company
shall have the right to use the UW Patent Rights and Technical Information for
research only. Company is expressly prohibited from selling any products or
services or developing any salable product or service based on the UW Patent
Rights or Technical Information until such time as a license agreement has been
fully executed between the parties.

3.4 Mutual Confidentiality. During the Option Period, Company shall maintain the
UW Technology, UW Patent Rights and Technical Information in confidence and
refrain from disclosing information related to UW Technology, UW Patent Rights
or Technical Information to a third party. In no event shall Company disclose,
or otherwise use UW Technology, UW Patent Rights or Technical Information in
connection with any patent application filed or on behalf of the Company.
Company agrees to restrict the use of UW Technology, UW Patent Rights and
Technical Information exclusively to the terms of this Agreement, provided that
such restriction does not include information that is in the public domain or
which company can show as derived prior to or independently from information
received from University. University's OTL (Office

[***] 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

                                                                UW-ActiveBiotics
                                                              OTL#1169-1291129DL
                                                                       6/13/2002

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Technology of Licensing) shall maintain in confidence and refrain from
disclosing proprietary Company information, including strategic business plans,
information regarding research, research plans, experimental results or other
proprietary information regarding the business of the Company to the extent
permitted by law. The University of Washington is a governmental agency of the
state of Washington and is subject to the Washington Public records Act, RCW
42.17.250 et seq., and no obligation assumed by University under this Agreement
shall be deemed to be inconsistent with University's obligations defined under
RCW 42.17. University shall provide notice to Company in a timely manner such
that Company is afforded sufficient time to review such documents and/or seek a
protective order, at Company's expense. The responsibility for protecting the
Confidential Information shall reside exclusively with Company utilizing the
procedures described in RCW 42.17.330

3.5 Exercise of Option. If Company wants to exercise the option hereunder it
must provide written notice to University within the term of this Agreement and
provide the University with an acceptable development plan that is similar in
scope and substance to that outlined in Exhibit A attached hereto. The Parties
agree to negotiate the terms of a license in good faith.

4. Option Fee and Payments.

4.1 Fee. As consideration for the option granted by University to Company for
the Option Period, Company agrees to pay to University a non-refundable,
non-creditable option fee of [***] Dollars (US$[***]), due within thirty (30)
days of the Effective Date of this Agreement.

4.2 Patent Prosecution and Cost Recovery

     4.2.1 During the Option Period, University, or its designee, shall have
sole control over the filing, prosecution and maintenance of any and all patent
applications included in UW Patent Rights, whether pending or not yet filed as
of the Effective Date of this Agreement, and of the maintenance and other
management of any and all issued patents included in UW Patent Rights

     4.2.2 During the Option Period, University shall keep Company informed of
the status of any and all new patents and/or patent applications that are part
of UW Patent Rights Company may provide comments to University on courses of
action with respect to the filing of new patent applications relating to UW
Technology, prosecution of patent applications, and/or management of patents in
UW Patent Rights, provided University shall have exclusive authority to
prosecute and maintain UW Patent Rights

     4.2.3 Company agrees to reimburse University for all fees and costs related
to the filing, prosecution and maintenance of patent applications, including,
without limitation, interference, oppositions, and reexaminations, and
maintenance and defense of patents, in patent fees and costs relating to UW
Patent Rights, whether incurred prior to the execution of this Agreement or
during the term of this Agreement. Such fees and costs shall not include costs
incurred by the University in the use of its own resources, such as employee
time, and shall not extend to patenting fees and costs incurred by University
after termination of this Agreement. Company agrees to pay invoices for
previously incurred fees and costs submitted by University in the amount of
Forty Thousand Eight Hundred and Forty-nine Dollars and Two cents
($40,849.02USD) according to the following schedule:

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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

                                                                UW-ActiveBiotics
                                                              OTL#1169-1291129DL
                                                                       6/13/2002

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                    -    Six (6) Months after the Effective date of this
                         Agreement: Twenty Thousand Four Hundred and Twenty-five
                         Dollars and Fifty-two Cents ($20,425 52USD);

                    -    Twelve (12) Months after the Effective Date of this
                         Agreement: Twenty Thousand Four Hundred and Twenty-five
                         Dollars and Fifty-two Cents ($20,425 52USD)

5. Termination

5.1 Termination by Company. Company has the right to terminate this Agreement
provided that Company gives University sixty (60) days prior written notice of
termination. Termination will be effective sixty (60) days from the date
University receives such notice.

5.2 Termination by University. University shall have the right to terminate this
Agreement, including the option granted to Company in Article 3.1, effective
immediately upon written notice of termination to Company in the event that
Company fails to meet the obligations of Articles 3.3, 3.4, 4.1, or 4.2.3 under
this Agreement and such failure or breach continues unremedied for a period of
sixty (60) days after receipt by Company of written notice thereof from
University. Termination will be effective sixty (60) days after the date Company
receives such notice and only in the event that Company does not cure the
failure or breach within that sixty (60) day period;

5.3 Automatic Termination. This Agreement, and the option granted to Company
hereinabove, shall terminate immediately in the event that (a) Company seeks
liquidation, reorganization, dissolution or winding-up of itself, is insolvent
or evidence exists as to its insolvency, or Company makes any general assignment
for the benefit of its creditors; (b) a petition is filed by or against Company,
or any proceeding is initiated by or against Company, or any proceeding is
initiated against Company as debtor, under any bankruptcy or insolvency law; or
(c) receiver, trustee, or any similar officer is appointed to take possession,
custody, or control of all or any part of Company's assets or property.

6. License Terms.

Upon University's receipt of notice and a development plan reasonably acceptable
to University pursuant to Article 3.5, University and Company shall enter into
good faith negotiations regarding the terms of a license agreement.

7. Miscellaneous Provisions.

7.1 Limitation of Liability of University. No term or provision of this
Agreement shall be construed as a warranty or representation by University
concerning the validity, scope or value of UW Technology, UW Patent Rights or
Technical Information. With respect to the subject matter of this Agreement,
Company and University are independent contractors and neither shall be deemed
to be an agent, employee, partner, nor joint-venturer of the other for any
purpose.

[***] 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

                                                                UW-ActiveBiotics
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                                                                       6/13/2002

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7.2 Indemnification. Company agrees to indemnify, hold harmless and defend
University, its regents, officers, inventors, employees, students, and agents
("Indemnified Parties") against any and all claims, causes of action, lawsuits,
or other proceedings ("Claims") and losses, damages, costs, fees and expenses
("Costs") filed, instituted, resulting from or arising out of the design,
process, manufacture or use by any person or party, of any Company Products
based on UW Patent Rights, UW Technology or Technical Information. Company
agrees to such indemnification even though such Claims or Costs related thereto
result in whole or in part from the negligence of any of the Indemnified Parties
or are based upon doctrines of strict liability or products liability. Such
indemnity shall not, however, apply to Claims arising from the gross negligence
or intentional misconduct of any Indemnified Party. This indemnification clause
shall survive the termination of this Agreement.

7.3 Entire Agreement. The Parties hereto acknowledge that this Agreement sets
forth the entire Agreement and understanding of the Parties hereto as to the
subject matter hereof and supersedes any and all prior written and oral
agreements, understandings or offers. This Agreement may not be modified,
changed or discharged in whole or in part, except by an agreement in writing
signed by authorized representatives of both Company and University.

7.4 Choice of Law/Venue. Because University is an agency of the state of
Washington, the Parties agree that this Agreement shall be governed by and
interpreted in accordance with the laws of the state of Washington, regardless
of choice of law provisions. The parties further agree that any claim related in
any manner to the Agreement shall be instituted and commenced in, and venue
shall be King County, Washington or the United States District Court for the
Western District of Washington.

7.5 Severability. Should any provision of this Agreement be determined to be
unenforceable or otherwise unlawful, then such provision shall be without
effect, and the remaining terms of this Agreement will survive, as if such
provision had not been included herein; and the Parties shall promptly meet to
agree upon further terms which shall, within the confines of the law, most
substantially satisfy the intention of the Parties as reflected by the
ineffective provision.

7.6 Waiver. No delay or omission by either Party in exercising any right under
this Agreement shall operate as a waiver of that or any other right. A waiver or
consent given by either Party on any one occasion is effective only in that
instance and shall not be construed as a bar to or waiver of any right on any
other occasion.

7.7 Notices and Reports. All notices, requests and other communications to
Company or University hereunder shall be in writing (including fax only if
transmittal sheet indicates confirmation), shall refer specifically to this
Agreement and shall be personally delivered or sent by fax or other electronic
transmission or by registered mail, or certified mail, return receipt requested,
postage prepaid, in each case to the respective addresses listed below (or to
such address as may be specified in writing to the other party hereto):

If to Company:

Active Biotics, Inc.
198 Broadway Street
Cambridge, MA 02139
Attn: Chief Executive Officer

[***] 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

                                                                UW-ActiveBiotics
                                                              OTL#1169-1291129DL
                                                                       6/13/2002

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Fax: 1-617-497-9688

If to University:

University of Washington
Office of Technology Licensing
1107 NE 45th St. Suite 200
Seattle, WA 98105
Attn: Director
Fax: (206)685-4767

7.8 Attorney's Fees. If any dispute shall arise under this Agreement, the
prevailing party shall be entitled to its reasonable attorneys' fees and costs
of litigation from the other party.

7.9 No License. This Agreement does not grant Company a license to UW
Technology, UW Patent Rights or Technical Information.

7.10 Use of Names, Trade Names and Trademarks. Nothing in this Agreement confers
the right upon a party to use the trade name, trademark, or name of the other
party in any advertising, publicity or other promotional activities, unless the
express, written permission of the other party has been obtained. The use of the
name "University of Washington," or any contraction, abbreviation, or simulation
thereof, by Company is expressly prohibited without prior written approval.

IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be duly
executed and delivered as of the Effective Date.

Company:

By: /s/ Chalom Sayada
    ------------------------------
    Name: Chalom Sayada, M.D, Ph.D
    Title: CEO
    Date: June 13th, 2002

University of Washington:

By: /s/ Anthony Claiborne
    ------------------------------
    Name: Anthony Claiborne
    Title: Director OTL
    Date: June 17, 2002

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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

                                                                UW-ActiveBiotics
                                                              OTL#1169-1291129DL
                                                                       6/13/2002

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                                    EXHIBIT A

                                DEVELOPMENT PLAN

A Development Plan of the scope outlined below shall be submitted to the
University of Washington ("University") within thirty (30) days of the execution
of this Agreement. In general, the Development Plan should provide the
University with a summary overview of the activities that Company believes are
necessary to bring products based on either UW Technology or UW Patent Rights to
the marketplace.

Development Program

Development Activities to be Undertaken
(please break activities into sub-units where appropriate with the anticipated
date of completion of major milestones.)

Estimated Total Development Time

Governmental Approval (if applicable)

Types of submissions required

Government Agency (e.g. FDA, EPA, etc)

Proposed Market Research

Competitive Information

Potential Competitors

Potential Competitive Devices/Compositions

Known Competitor's plans, developments, technical achievements

D. Perceived Advantage Over Competitors

Anticipated Date of Product Launch

Total Length: approximately 2-3 pages.

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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

                                                                UW-ActiveBiotics
                                                              OTL#1169-1291129DL
                                                                       6/13/2002

<Page>

                                    EXHIBIT B

              AGREEMENT BETWEEN UNIVERSITY OF WASHINGTON AND A SHOR

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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

                                                                UW-ActiveBiotics
                                                              OTL#1169-1291129DL
                                                                       6/13/2002

<Page>

                                   EXHIBIT 1.2

                                   Affiliates

As of the Effective Date, there are no Affiliates.

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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

                                       24

<Page>

                                  EXHIBIT 1.17

                     Issued patents as of the Effective Date

United States Patent Number:   6,043,225

Title:                         Diagnosis and Treatment of Arterial Chlamydial
                               Granuloma

Application Date:              3/28/2000

Assignee:                      University of Washington and Allan Shor*

United States Patent Number:   5,830,874

Title:                         Diagnosis and Treatment of Arterial Chlamydial
                               Granuloma

Application Date:              11/3/1998

Assignee:                      University of Washington and Allan Shor*

United States Patent Number:   5,424,187

Title:                         Diagnosis and Treatment of Arterial Chlamydial
                               Granuloma

Application Date:              6/13/1995

Assignee:                      University of Washington and Allan Shor*

*    Exclusively controlled by University of Washington under separate agreement
     with Allan Shor

[***] 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

                                       25<Page>

                                                                    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
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                                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

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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

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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-

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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.

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

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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

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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

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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

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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

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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

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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

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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

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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.

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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

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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.

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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.

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TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
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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.

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TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
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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

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TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
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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

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

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                                                                  EXECUTION COPY

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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                                                                  EXECUTION COPY

     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

License Agreement between Metaphore Pharmaceuticals, Inc. and Pfizer Inc

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                                                                  EXECUTION COPY

                            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

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

                                       25

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                                                                  EXECUTION COPY

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

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

                                       26

<Page>

                                                                  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

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

                                       27

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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

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

                                       28

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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

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

                                       29

<Page>

                                                                  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

<Page>

                         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

<Page>

    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.

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