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                                                                   Exhibit 10.10

                                                                  EXECUTION COPY

                           EXCLUSIVE LICENSE AGREEMENT

     THIS EXCLUSIVE LICENSE AGREEMENT (this "Agreement") is entered into on the
14th day of February 2005, by and between EndoChem, Inc., a corporation
organized and existing under the laws of the State of California having its
principal place of business at 1751 Capistrano Ave, Berkeley, California
94707-1805 ("EndoChem"), and QuatRx Pharmaceuticals Company, a corporation
organized and existing under the laws of the State of Delaware having its
principal place of business at 777 East Eisenhower Parkway, Suite 100, Ann
Arbor, Michigan 48108-8935 (hereinafter called "Licensee"). EndoChem and
Licensee are each individually referred to herein as a "Party" and collectively
as the "Parties".

     WHEREAS, EndoChem owns or has license rights to certain inventions that are
described in the "Licensed Patents" defined below, and EndoChem is willing to
grant a license to Licensee and Licensee desires a license under the Licensed
Patents;

     NOW, THEREFORE, in consideration of the mutual covenants and agreements set
forth below, the parties covenant and agree as follows:

SECTION 1. DEFINITIONS.

The following capitalized terms shall have the meanings set forth below:

     1.1 "Affiliate" shall mean, with respect to a given entity, any other
entity (including any individual) which, directly or indirectly, Controls, is
Controlled by or is under common Control with such entity. "Control" for the
purpose of this Section 1.1 means (i) having the actual, present capacity to
elect a majority of the directors of such entity; (ii) having the power to
direct at least fifty percent (50%) of the voting rights entitled to elect
directors; or (iii) in any country where the local law will not permit foreign
equity participation of a majority, ownership or control, directly or
indirectly, of the maximum percentage of such outstanding stock or voting rights
permitted by local law.

     1.2 "Agreement" has the meaning set forth in the first paragraph.

     1.3 "Attributed Income" shall mean the total gross proceeds (excluding from
such proceeds Sublicensee Royalties of Sublicensees and Earned Royalties, but
including in such proceeds, without limitation, any license fees, maintenance
fees, or milestone payments), whether consisting of cash or any other form of
consideration and whether or not any rights other than Patent Rights are
granted, which gross proceeds are received by or payable to the Licensee and/or
any of its Affiliates from any Sublicensee in consideration of the grant of a
sublicense and from any Development Partner in consideration of any agreement or
arrangement between such Development Partner and Licensee or Sublicensee in
connection with an agreement or arrangement relating to the research or
development of Licensed Products. Notwithstanding the foregoing, Attributed
Income shall not include proceeds reasonably and fairly attributed in such
sublicense or such agreement or arrangement to bona fide (i) debt financing;
(ii) equity (and conditional equity, such as warrants, convertible debt and the
like) investments in the Licensee at market value; (iii) reimbursements of
Patent

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Prosecution Costs actually incurred by Licensee; (iv) reimbursement for the
cost of research and/or development services to be provided by Licensee on a
going forward basis (or within the six (6) month period preceding the
consummation of such sublicense or such agreement or arrangement, so long as the
reimbursement in question is specifically agreed upon between Licensee and such
Sublicensee or Development Partner in view of the negotiation period involved)
which is payable on a commercially reasonable full-time equivalent ("FTE") basis
or other similar commercially reasonable basis where reference to FTEs is not
applicable; (v) amounts paid for the supply of Licensed Products by Licensee to
a Sublicensee or a Development Partner or by a Sublicensee to a Development
Partner for preclinical or clinical development (so long as amounts received for
such supply do not exceed ********* percent (***%) of the actual fully burdened
manufacturing cost thereof); and (vi) reimbursement of reasonable out-of-pocket
costs actually paid by Licensee to third parties in connection with the services
described in subsection (iv) above to the extent such costs are not already
included in subsections (iv) or (v). For the avoidance of doubt, any gross
proceeds meeting the definition set forth above shall be "Attributed Income"
irrespective of whether such gross proceeds are received under one or more
separate agreements and irrespective of how such gross proceeds are referred to
or characterized by Licensee, the Sublicensee or the Development Partner.
Although Attributed Income shall include all aggregate proceeds meeting the
foregoing definition, regardless of whether the underlying sublicense or
agreement or arrangement includes other intellectual property or technology
besides the Patent Rights, in the event this results in a very substantial and
disproportionate amount of proceeds attributable solely to such other
intellectual property or technology to be included in Attributed Income so as to
impose an overly burdensome and inequitable obligation on Licensee, Licensee may
reasonably request EndoChem to make appropriate adjustment to Attributed Income
in such a particular case to mitigate such burden and inequity, which request
EndoChem shall consider in good faith. Notwithstanding the foregoing, however,
the Parties understand and agree that the negotiated Sublicense Fee rate in
Section 6.2 already presumes that additional value, technology and intellectual
property will be included in any transaction generating a given amount of
Attributable Income and that the mere inclusion of such additional value,
technology and/or intellectual property shall not, by itself, be sufficient to
justify any such adjustment.

     1.4 "Claim" has the meaning set forth in Section 11.1.

     1.5 "Combination Product" shall mean a combined Product that contains or
uses a Licensed Product as an active ingredient and at least one other Product
or process that is not a Licensed Product (a "Combination Product Component"),
where (i) if such Combination Product Component were removed from such combined
Product, the manufacture, use, Sale or import of the resulting Product in or
into a particular country would infringe, but for a license, the same Valid
Claim in the country where such manufacture, use, Sale or import occurs as such
Combination Product, (ii) such Combination Product Component is either a
separate active ingredient with independent therapeutic functionality or a
specialized delivery device (thus excluding, for example and without limitation,
adjuvants, conjugates, excipients, syringes and similar components), and (iii)
the market price of such combined Product is higher than the market price for
(or, if no such price exists, the fair market value of) such Licensed Product as
a result of such combined Product containing or using such Combination Product
Component.

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     1.6 "Commencement" shall mean, in connection with a clinical trial, the
first dosing of the first patient in such trial.

     1.7 "Confidential Information" has the meaning set forth in Section 9.1.

     1.8 "Control" shall mean, with respect to an item of information or
intellectual property right, that a Party or one of its Affiliates owns or has a
license to such item or right and has the ability to disclose to the other Party
and grant a license or sublicense under such item or right as provided for in
this Agreement without violating the terms of any agreement with or other
obligation to any Third Party.

     1.9 "Development Partner" shall mean any person or entity other than a
Sublicensee that has an agreement or arrangement with the Licensee, its
Affiliates or any Sublicensee for the conduct of research or development of
Licensed Products.

     1.10 "Disclosing Party" has the meaning set forth in Section 9.1.

     1.11 "Earned Royalty" shall mean any Sublicensee Royalty and/or any
Royalty.

     1.12 "Effective Date" shall mean the later of (i) the date upon which this
Agreement is entered into, as set forth in the first paragraph, and (ii) the
date upon which each of this Agreement, the UC Agreement, and the letter
agreement by and between QuatRx and UC relating to Section 3.1.2 of the UC
Agreement are executed by all parties thereto. QuatRx shall notify EndoChem in
writing when it has executed the letter agreement between it and UC.

     1.13 "FDA" shall mean the United States Food and Drug Administration, or a
successor federal agency thereto.

     1.14 "Field of Use" shall mean the use of Licensed Product or Licensed
Method for all human therapeutic applications, including, but not limited to,
the treatment of hyperlipidemia, obesity and diabetes. The Field of Use
specifically excludes all uses and applications other than human therapeutic
applications.

     1.15 "First Commercial Sale" shall mean the first Sale of a Licensed
Product to a Third Party (other than an Affiliate or Sublicensee) in a
jurisdiction after Regulatory Approval.

     1.16 "Invention" has the meaning set forth in Section 10.2.

     1.17 "Inventor" has the meaning set forth in Section 10.2.

     1.18 "Licensed Method" shall mean any process, art or method the use or
practice of which, but for the license granted in this Agreement, would
infringe, or contribute to, or induce the infringement of, any Licensed Patents
in any country were they issued at or prior to the time of the infringing
activity in that country.

     1.19 "Licensed Patents" shall mean: (i) the Patent Rights; (ii) any other
patents and patent applications that are now or hereafter Controlled by EndoChem
that are (a) necessary to make, use or sell the composition of matter of any
compound, or to practice a method,

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claimed by the Patent Rights in subsection (i), or (b) necessary to make or use
the composition of matter of any intermediates used to make the foregoing
compounds; and (iii) any patents and patent applications on inventions made by
EndoChem during its participation on the Steering Committee, in each case
including any foreign counterparts thereof, and any continuations,
continuations-in-part, divisions, re-issues, additions, reexaminations, renewals
and extensions thereof, and any patents issuing from any such patent
applications in any jurisdiction in the Territory. In no event shall the
Licensed Patents include any patents or patent applications Controlled by
EndoChem that claim any methods of manufacturing or formulations of the
compositions of matter claimed by the Patent Rights, unless such patents and
patent applications are described in (i) or (ii).

     1.20 "Licensed Product" shall mean any Product, including, without
limitation, a Product for use or used in practicing a Licensed Method and any
Product made by practicing a Licensed Method, the manufacture, use, Sale, offer
for Sale or import of which, but for the license granted in this Agreement,
would infringe, or contribute to, or induce the infringement of, any Licensed
Patents in any country were they issued at or prior to the time of the
infringing activity in that country.

     1.21 "Licensee" has the meaning set forth in the first paragraph.

     1.22 "Net Invoice Price" shall mean (a) the gross invoice price or, if no
invoice is issued for the Sale of Licensed Product, the amount otherwise charged
by the Licensee and/or any Sublicensee for a Licensed Product or a Licensed
Method, or (b) in those instances where the Licensed Product is combined in any
manner with any other Product or service, the gross invoice price or, if no
invoice is issued for the Sale of Licensed Product, the amount otherwise charged
by the Licensee and/or any Sublicensee for the combined Product or service in
its entirety, less the following items, but only to the extent that they
actually pertain to the disposition of such Licensed Product and are separately
billed:

          (i) Allowances actually granted to customers for rejections, returns
     and prompt payment and volume discounts;

          (ii) Freight, transport packing and insurance charges associated with
     transportation to the extent included in the gross invoice price;

          (iii) Taxes, including Deductible Value Added Tax, tariffs or
     import/export duties based on Sales when included in the gross invoice
     price, but excluding value-added taxes other than Deductible Value Added
     Tax or taxes assessed on income derived from Sales, where "Deductible Value
     Added Tax" means value added tax only to the extent that such value added
     tax is actually incurred and is not reimbursable, refundable or creditable
     under the tax authority of any country;

          (iv) Only those normal and customary discounts and rebates that are
     given as part of a formulary program and are paid or credited to customers,
     third-party payers, healthcare systems, or administrators for a Licensed
     Product that is included in such formulary program, as permitted by
     applicable law;

          (v) Only those normal and customary wholesaler's discounts and rebates
     that are given as part of a formulary program and are paid or credited to

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     customers, third-party payers, health care systems, or administrators for a
     Licensed Product that is included in such formulary program, as permitted
     by applicable law; and

          (vi) Rebates and discounts which are reasonable and customary in the
     industry paid or credited as permitted by applicable law.

     1.23 "Net Sale" shall mean:

          (i) except in the instances described in Sections (ii), (iii), (iv),
     (v), (vi), and (vii) of this definition, the Net Invoice Price;

          (ii) for any Relationship-Influenced Sale of a Licensed Product, Net
     Sales shall be based on the Net Invoice Price (calculated as if the
     Relationship-Influenced Sale Purchaser was a Sublicensee) at which the
     Relationship-Influenced Sale Purchaser resells such Licensed Product in
     lieu of the Net Invoice Price of the Licensee and/or any Sublicensee with
     respect to such Licensed Product;

          (iii) in those instances where Licensed Product is not Sold, but is
     otherwise used for purposes other than those directed toward the further
     research and development (including without limitation for quality
     assurance, quality control, compound assays, or similar activities, whether
     conducted pre- and/or post-approval) of Licensed Products, (a) the Net
     Sales for such Licensed Product shall be the Net Invoice Price of such
     Licensed Products if then being commercialized, or (b) if such Licensed
     Products are not then being commercialized, the Net Sales for such Licensed
     Product shall be the Net Invoice Price of similar products or services Sold
     in similar quantities in an arm's length transaction by Licensee, a
     Sublicensee or, if not Sold by Licensee or a Sublicensee, by any other
     manufacturer (taking into account, however, the fact (if true) that the
     Licensed Product in question is not then being produced in commercial
     quantities, in which case a reasonable discount shall be applied), or (c)
     if subsection (a) does not apply and similar products or services are not
     then being Sold by Licensee, a Sublicensee or any other manufacturer, then
     the Net Sale of the Licensed Product so used for such a purpose shall be
     Licensee's or the Sublicensee's ********** such Licensed Product
     (determined in accordance with generally accepted accounting principles)
     plus an additional **** percent (**%) thereof;

          (iv) in those instances where the Licensee or any Sublicensee acquires
     a Licensed Product and then subsequently Sells or otherwise uses (as
     described in Section (iii)) such Licensed Product, Net Sales shall mean the
     Net Invoice Price charged upon the Sale or other use of such Licensed
     Product by the Licensee or any Sublicensee, with the resulting royalty
     amount due to UC subject to a deduction for any royalty amounts paid to UC
     on account of an earlier Sale or other use (as described in Section (iii))
     of such Licensed Product, if any;

          (v) in the event Licensee or its Sublicensee Sells or otherwise uses
     (as described in Section (iii)) any Licensed Product in the Territory in
     the form of a Combination Product containing one or more active ingredients
     which are themselves not Licensed Products (which may be either combined in
     a single formulation or bundled with separate formulations but sold as one
     product), (a) Net

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     Sales for such Combination Product will be calculated by multiplying actual
     Net Sales of such Combination Product (i.e., calculated as if the entire
     Combination Product is one Licensed Product) by the fraction A/(A+B) where
     A is the standard arms-length invoice price of the Licensed Product within
     such Combination Product if sold separately, and B is the total standard,
     arms-length invoice price of the other active ingredient or ingredients in
     the Combination Product, if sold separately (with Section (iii) being used
     to calculate the Net Invoice Price of a Licensed Product used as described
     in such paragraph) or (b) if, on a country-by-country basis, the other
     active ingredient or ingredients in the Combination Product are not sold
     separately in said country, Net Sales for the purpose of determining
     royalties of the Combination Product shall be determined by the Parties in
     good faith and in a manner consistent with the intent of this Agreement
     (Net Sales shall be determined in a manner consistent for all Licensed
     Products and in accordance with GAAP, and notwithstanding any of the
     foregoing to the contrary, in no event shall Net Sales for a Combination
     Product be **** **** percent (**%) of Net Sales, calculated without
     regard to the formulas set forth above, of the entire Combination Product);

          (vi) transfers or dispositions of Licensed Products for no
     consideration or for consideration at or below the manufacturing cost
     thereof in commercially reasonable quantities for charitable (i.e. for use
     in an investigator initiated studies by a not-for-profit entity or for
     compassionate use purposes) or promotional purposes or for preclinical,
     clinical, manufacturing scale-up, regulatory or governmental (i.e. required
     by a governmental authority to be supplied to a governmental authority for
     use by such governmental authority) purposes shall not be included in the
     calculation of Net Invoice Price or Net Sales;

          (vii) except as otherwise provided in Section (ii), if Licensee or a
     Sublicensee Sell a Licensed Product other than in a bona fide arm's length
     transaction exclusively for cash consideration, such Sale shall be deemed
     to constitute a Sale invoiced at the relevant market value of such Licensed
     Product in the country in which the sale occurs, or, if that price is not
     ascertainable, then it shall be deemed to constitute a sale invoiced at a
     reasonable price assessed on an arm's length basis for such Licensed
     Product in such country; and

          (viii) to the extent Licensee and/or any Sublicensee receives any cash
     amounts or any non-cash consideration for the Sale of Licensed Products
     that are not otherwise included in the Net Invoice Price and that are not
     otherwise addressed in the foregoing subsections of this Section, then the
     Net Invoice Price shall be deemed to include such additional cash amounts
     and the fair market value of such non-cash consideration so received for
     such Sale of such Licensed Products.

     1.24 "New Developments" shall mean inventions, or claims to inventions,
made by UC which constitute advancements, developments or improvements to the
technology claimed in Valid Claims in the Patent Rights, whether or not
patentable and whether or not the subject of any patent application, which are
not sufficiently supported by the specification of a previously-filed patent or
patent application within the Patent Rights to be entitled to the priority date
of the previously-filed patent or patent application.

     1.25 "Party" or "Parties" has the meaning set forth in the first paragraph.

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          1.26 "Patent Prosecution Costs" shall mean the costs of preparing,
     filing, prosecuting and maintaining all United States and foreign patent
     applications contemplated by this Agreement.

          1.27 "Patent Rights" shall mean the Valid Claims of the following
     United States patents and patent applications:

<TABLE>
<CAPTION>
                 Patent Application Number
UC Case Number        or Patent Number          Filing or Issue Date
--------------   -------------------------   -------------------------
<S>              <C>                         <C>
    *****                *********                    ******
                         *********                    ******
                         *********                    ******
                         *********                    ******
                         *********                    ******
                         *********                    ******
                         *********                    ******
                         *********                    ******
    *****                *********                    ******
    *****                *********                    ******
    *****                *********                    ******
                         *********                    ******
                         *********                    ******
                         *********                    ******
</TABLE>

     Patent Rights shall further include: (a) the Valid Claims of the foreign
patents and patent applications corresponding to the patents and patent
applications listed above (and all patents and patent applications (i) requested
under Section 10.1.4 herein after the Effective Date, or, (ii) with respect to
patents and patent applications requested prior to the Effective Date, as to
which Licensee has complied with its obligation to bear the Patent Prosecution
Costs thereof); and (b) any reissues, reexaminations, extensions and
substitutions, and any continuation, division, and continuation-in-part
applications (provided that Valid Claims in the continuation-in-part
applications are included in the Patent Rights only if entirely supported in the
specification of, and entitled to the priority date of, a parent application
listed in the

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chart above), all to the extent assigned to or otherwise obtained by UC. This
definition of Patent Rights excludes any rights in and to New Developments.

     1.28 "Product" shall mean any kit, article of manufacture, composition of
matter, material, compound, component or product.

     1.29 "Regulatory Approval" shall mean all approvals by government pricing
and health authorities in a country or supra-national organization (including,
but not limited to the FDA and its foreign equivalents), product licenses,
registrations and authorizations of all national and international regulatory
agencies, departments, bureaus and other governmental entities, in each case
that are necessary for the commercial manufacture, use, storage, importation,
export, transport and Sale of Licensed Products in a regulatory jurisdiction.

     1.30 "Related Party" shall mean a corporation, firm or other entity with
which, or individual with whom, the Licensee, any Sublicensee and/or any
Development Partner (or any of their respective Affiliates) have any agreement,
understanding or arrangement (for example, but not by way of limitation, an
option to purchase stock or other equity interest, or an arrangement involving a
division of revenue, profits, discounts, rebates or allowances) unrelated to the
Sale or use of the Licensed Products without which such other agreement,
understanding or arrangement, the amounts, if any, charged by the Licensee or
any Sublicensee to such entity or individual for the Sale of Licensed Product,
would be higher than the Net Invoice Price actually received, or if such
agreement, understanding or arrangement results in the Licensee or any
Sublicensee extending to such entity or individual lower prices for the Sale of
such Licensed Product than those charged to others without such agreement,
understanding or arrangement buying similar products or services in similar
quantities.

     1.31 "Relationship-Influenced Sale" shall mean a Sale or use of a Licensed
Product or use of a Licensed Method between the Licensee and/or any Sublicensee
and (i) an Affiliate of such entity (wherein, for purpose of this definition,
Affiliate shall be defined by reference to the 40% ownership standard rather
than the 50% standard in the "Affiliate" definition above); (ii) a Related Party
or (iii) the Licensee, a Sublicensee and/or a Development Partner.

     1.32 "Relationship-Influenced Sale Purchaser" shall mean the purchaser of
Licensed Product in a Relationship-Influenced Sale.

     1.33 "Royalty" shall have the meaning set forth in Section 6.4.

     1.34 "Royalty Term" shall mean, with respect to a particular Licensed
Product in any country in the Territory, the period of time commencing on the
First Commercial Sale of such Licensed Product in such jurisdiction and ending
upon the expiration of the last to expire Licensed Patent containing a Valid
Claim which would be infringed by the manufacture, use, importation, offer for
Sale, or Sale of such Licensed Product in such country.

     1.35 "Sale" shall mean the act of selling, leasing or otherwise
transferring, providing, or furnishing for use for any consideration.
Correspondingly, "Sell" means to make or cause to be made a Sale and "Sold"
means to have made or caused to be made a Sale.

     1.36 "Steering Committee" shall have the meaning set forth in Section 3.2.

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     1.37 "Subcontractor" shall mean a Third Party that has been retained by a
Licensee or Sublicensee hereto to perform specific research, development or
manufacturing activities on a fee-for-service basis.

     1.38 "Sublicense Fees" shall have the meaning set forth in Section 6.2.

     1.39 "Sublicensee" shall mean any person or entity (excluding any
Subcontractor, Development Partner or distributor) to which any of the license
rights granted to the Licensee hereunder are sublicensed.

     1.40 "Technical Information" shall mean any and all know-how, trade secret
or other information of a technical nature necessary for the manufacture, use,
or sale of the composition of matter of any compound, or practice of any method,
claimed by the Licensed Patents in Section 1.19(i) that is Controlled by
EndoChem.

     1.41 "Territory" shall mean the world.

     1.42 "Third Party" shall mean any individual or entity other than the
Parties or their respective Affiliates.

     1.43 "UC" shall mean The Regents of the University of California.

     1.44 "UC Agreement" shall mean that certain License Agreement between
EndoChem and the UC dated February 14, 2005.

     1.45 "Valid Claim" shall mean a claim of a patent or patent application in
any country, whether existing as of the Effective Date or thereafter, that (i)
has not expired; (ii) has not been disclaimed; (iii) has not been cancelled or
superseded, or if cancelled or superseded, has been reinstated; and (iv) has not
been revoked, held invalid, or otherwise declared unenforceable or not allowable
by a tribunal or patent authority of competent jurisdiction over such claim in
such country from which no further appeal has or may be taken.

SECTION 2. GRANT.

     2.1 License. EndoChem hereby grants to Licensee an exclusive, sublicensable
(subject to Section 2.2 below), royalty-bearing license in the Territory under
the Licensed Patents Controlled by EndoChem to make, have made, use, Sell, have
Sold, offer for Sale and import and export Licensed Products and to practice
Licensed Patents, in each case in the Field of Use. Licensee acknowledges that
the Licensed Patents licensed to EndoChem pursuant to the UC Agreement exist
only in certain countries in the Territory.

          2.1.1 Licensee's rights under the Patent Rights shall be subject to
     the restrictions set forth in Sections 2.2 thru 2.5 and 3.1 of the UC
     Agreement, which is attached hereto as Exhibit A (with certain portions
     redacted). Licensee and each Sublicensee (as authorized under Section 2.2
     below) shall comply with all applicable terms, conditions, obligations and
     other restrictions of the UC Agreement that protect or benefit UC's (and,
     if applicable, the United States Government's and other sponsors') rights
     and interests, other than those terms, conditions and obligations specified
     in

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     Article 6 (License Issue Fee), Article 7 (License Maintenance Fee) and
     Paragraph 9.3 (Minimum Annual Royalty), Article 10 (Milestone Payments) and
     Paragraphs 21.4 and 21.6 (reimbursement for Patent Prosecution Costs) of
     the UC Agreement (although the foregoing shall not limit Licensee's
     obligations to make the payments it is required to make under this
     Agreement to EndoChem). Licensee shall attach a copy of the UC Agreement to
     each sublicense issued under Section 2.2 below and shall specify in the
     sublicense that the sublicensee must comply with the terms of the UC
     Agreement to the extent required in the previous sentence.

          2.1.2 Within five (5) days of the date hereof, EndoChem shall deliver
     to Licensee, at EndoChem's cost, copies of all materials embodying the
     Licensed Patents and Technical Information Controlled by EndoChem and any
     other information, data or materials, whether or not in a tangible medium,
     relating to or necessary for the research and/or development of Licensed
     Products or the practice of Licensed Methods.

          2.1.3 Licensee shall provide EndoChem with a written copy of any
     correspondence or notice Licensee sends to UC under Section 3.1.2 of the UC
     Agreement concurrently with its provision of such notice to UC. EndoChem
     further agrees that notwithstanding the terms of Section 3.1.2 of the UC
     Agreement, Licensee shall not be required to seek or obtain EndoChem's
     consent under such Section 3.1.2 of the UC Agreement prior to or as a
     condition of asserting its rights as described in Section 3.1.2 of the UC
     Agreement to continue to exercise the rights sublicensed by EndoChem to
     Licensee hereunder. EndoChem does not waive or forego any other rights it
     may have under the UC Agreement or at law or equity, with respect to any
     rights obtained by EndoChem under the UC Agreement.

          2.1.4 During the term of this Agreement, EndoChem shall not (a)
     directly or indirectly, license or otherwise grant to any Third Party any
     rights or licenses, including, without limitation, the right to grant
     sublicenses in, to and under the Licensed Patents or Technical Information,
     to make or have made, use, have used, have imported, Sell, offer for Sale
     or have Sold the Licensed Product(s) and/or Licensed Methods in the Field
     of Use, or (b) directly or indirectly, use, develop, manufacture, market,
     distribute, import, export, license to, Sell or offer for Sale, or assist a
     Third Party in using, developing, manufacturing, marketing, distributing,
     importing, exporting, licensing, Selling or offering for Sale, a Licensed
     Product or Licensed Method which incorporates or otherwise exploits a
     compound that has activity as ******************. EndoChem shall not amend,
     modify, breach or terminate the UC Agreement and shall provide Licensee a
     copy of any notice EndoChem receives from UC alleging breach by EndoChem,
     and confer with Licensee to determine how to respond to any such notice.
     Notwithstanding the foregoing, (i) any breach or termination of the UC
     Agreement arising from Licensee's breach of its obligations under this
     Agreement shall not constitute a breach of EndoChem's obligations in the
     prior sentence, and (ii) Licensee will reasonably consider in good faith
     and not unreasonably withhold or delay its consent to any proposal by
     EndoChem to amend or modify the UC Agreement in any manner that does not
     affect Licensee's rights under this Agreement.

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     2.2 Sublicenses. Affiliates of Licensee shall have no licenses under this
Agreement unless Licensee grants a sub-license to such Affiliates. Licensee may
only sublicense to its Affiliates or other parties to the extent reasonably
necessary for the development and commercialization of Licensed Products in
accordance with this Agreement. Each Sublicensee must be subject to a written
sublicense agreement. Such sublicenses shall contain terms, conditions,
obligations and other restrictions that are consistent with those in this
Agreement. For the purposes of compliance with this Agreement, Licensee shall be
responsible to ensure that its Sublicensees comply with the terms of this
Agreement, and accordingly, the operations of all Sublicensees shall be deemed
to be the operations of the Licensee, for which the Licensee shall be
responsible. Sublicensees who have received a direct sublicense from Licensee
under this Article 2 may grant further sublicenses (without further rights to
sublicense) solely for the purpose of developing, manufacturing and/or
commercializing, in collaboration with Licensee, Licensed Products developed
and/or commercialized in material part by Licensee or EndoChem. Any such
sublicense (a) shall not be granted on a stand-alone basis, where the term
"standalone" means that a sublicense is granted to an entity for the
development, manufacture or commercialization of Licensed Products without
EndoChem or Licensee or any such direct Sublicensee participating or having
participated in the development or commercialization of Licensed Products in
material part (i.e., without Licensee or EndoChem or any such direct Sublicensee
having incurred more than ******** dollars ($*****) in costs related to
the development, manufacture or commercialization of Licensed Products); (b)
shall not allow for further sublicensing of any such rights; and (c) shall be
subject to the terms and conditions herein. For the avoidance of doubt, Licensee
and any permitted Sublicensee can engage independent contractors such as
manufacturers, clinical trial organizations, and work-for-hire research
laboratories (such as those who conduct assays on a fee for service basis) so
long as the work conducted by such entities is being conducted on Licensee's or
such Sublicensee's behalf and such contracting entity does not receive rights to
develop, manufacture, use or commercialize Licensed Products outside of, or
after it completes, its services. Licensee shall require appropriate reporting
from all Sublicensees to establish all amounts owed hereunder, and shall make
such reports available to EndoChem. Licensee shall require all Sublicensees to
comply with the audits and obligations set forth in Section 6.7 as if they were
Licensee and to submit to Licensee progress reports and financial reports
consistent with this Agreement. Licensee shall make all of the foregoing reports
available to EndoChem. Licensee understands and agrees that EndoChem may provide
the information in these reports to UC, in accordance with EndoChem's reporting
requirements under the UC Agreement. Licensee shall require that Sublicensees
indemnify UC as provided for in Section 11 of this Agreement.

          2.2.1 The Licensee will identify each Sublicensee to EndoChem and will
     notify EndoChem of each sublicense granted hereunder (including, without
     limitation, any sublicenses granted by any Sublicensee and any sublicense
     granted to or by Licensee) and will provide EndoChem with a complete copy
     of each such sublicense and each amendment to such sublicense within twenty
     (20) days of issuance of such sublicense or such amendment.

     2.3 Mandatory Sublicensing.

          2.3.1 If UC provides a written notice to EndoChem under the UC
     Agreement of evidence supporting any commercially reasonable application or
     use for Products (the "New Product Use"), the manufacture, use or Sale of
     which are claimed in the Patent

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     Rights, (other than Licensed Products which are currently being Sold by
     Licensee), within the Field of Use but for which Licensed Products have not
     been developed or are not, at such time, being developed by Licensee, then
     EndoChem shall immediately give written notice to Licensee thereof, along
     with a copy of such notice from UC.

          2.3.2 Within ninety (90) days of Licensee's receipt of such notice,
     Licensee shall give EndoChem written notice stating whether Licensee agrees
     to develop and commercialize Licensed Products for such application either
     itself or with or through a Sublicensee ("New Licensed Products"). If
     Licensee so agrees, such notice shall be accompanied by (i) a detailed
     development schedule, including specific diligence requirements and
     development milestones, for the development of New Licensed Products; and
     (ii) a detailed business plan for the development, marketing and
     commercialization of New Licensed Products (collectively, the "Development
     Plan"). If (a) Licensee has not notified EndoChem, in accordance with the
     foregoing, that Licensee agrees to develop and commercialize such New
     Licensed Product within such ninety (90) day period, or if (b) the
     Development Plan is not reasonably acceptable to UC, then Licensee shall be
     deemed to not so agree provided that as to (b), EndoChem so notifies
     Licensee in writing providing the basis for UC's determination, cooperates
     with Licensee's efforts to discuss such business plan with UC, and Licensee
     fails to provide an updated business plan reasonably acceptable to UC
     within thirty (30) business days after receiving such written notice.

          2.3.3 If Licensee agrees, as set forth in Section 2.3.2, to develop
     and commercialize such New Licensed Product, then Licensee shall (a)
     diligently proceed with the development, manufacture and commercialization
     of such New Licensed Product and earnestly and diligently endeavor to
     market the same in accordance with the Development Plan and in quantities
     sufficient to meet market demand, either itself or with or through a
     Sublicensee; and (b) Licensee shall submit a written progress report
     setting forth in detail the status of such development, manufacture and
     commercialization every six (6) months to EndoChem, which may provide such
     report to UC as required under the UC Agreement.

          2.3.4 If Licensee does not agree, as set forth in Section 2.3.2, to
     develop and commercialize such New Licensed Product, but instead notifies
     EndoChem in writing that development of the New Licensed Product would
     impair Licensee's ability to develop or commercialize Licensed Products
     then under development or being commercialized by Licensee on a
     commercially reasonable basis (for example, if such New Licensed Product
     were useful for an indication or use for which Licensee, its Sublicensees
     or Development Partners are then developing or commercializing Licensed
     Products, if such New Licensed Product contained the same or a
     substantially similar active ingredient as a Licensed Product then being
     developed or commercialized by Licensee, its Sublicensees or Development
     Partners), then the Parties shall meet with UC to discuss the basis for
     Licensee's belief and any basis for UC's disagreement with such basis for
     Licensee's belief for a period of thirty (30) days.

          2.3.5 If Licensee does not agree, as set forth in Section 2.3.2, to
     develop and commercialize such New Licensed Product, or if Licensee fails
     to diligently pursue the development and commercialization thereof in
     accordance with the Development Plan, or if UC does not agree (in
     accordance with Section 2.3.4) that development of

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     New Licensed Products would impair Licensee's ability to develop or
     commercialize Licensed Products on a commercially reasonable basis , then
     UC has the right to seek one or more Third Parties for the development and
     commercialization of such New Licensed Product and refer such Third Party
     to EndoChem, which shall refer such Third Party to Licensee, so that such
     Third Party may request a sublicense allowing for development and
     commercialization of such New Licensed Product. If the Third Party requests
     a sublicense, then Licensee shall report such request to EndoChem, together
     with the terms and conditions thereof, within thirty (30) days from the
     date of such request.

          2.3.6 If Licensee does not grant a sublicense to the Third Party
     within a reasonable time after such request (and, in any event, within
     ninety (60) days after such request), or refuses to grant such sublicense
     under reasonable terms, then Licensee shall promptly, or, in the event of
     such refusal, within thirty (30) days after such refusal, submit to
     EndoChem (which shall in turn submit to UC) a written report specifying the
     license terms proposed by the Third Party and a written justification for
     the Licensee's refusal or failure to grant such sublicense. If UC
     determines that the terms of the sublicense proposed by the Third Party are
     reasonable under the circumstances, then UC has the right to grant to the
     Third Party (and the rights granted to Licensee in this Agreement shall be
     limited accordingly) a license to make, have made, use, Sell, offer for
     Sale and import Licensed Products, and to practice the Licensed Methods
     claimed in the Patent Rights (within the Field of Use and otherwise), but
     only to the extent necessary to research, develop and commercialize such
     Licensed Products for such New Product Use, at substantially the same terms
     last proposed to Licensee by the Third Party provided that the royalty
     rates are not lower than the earned royalties owed by EndoChem to UC under
     the UC Agreement. Any such grant of a license by UC to such a Third Party
     shall be deemed to restrict the license granted to Licensee under Section
     2.1 to the extent necessary to permit such Third Party to conduct such
     activities, and shall not be deemed a breach of this Agreement by EndoChem.

          2.3.7 In the event that Licensee reasonably believes that (a) the
     evidence provided by UC under Section 2.3.1 does not support any
     commercially reasonable application or use for Products, (b) UC
     unreasonably rejected the Development Plan provided by Licensee under
     Section 2.3.2, or (c) the terms proposed by a Third Party and granted by UC
     as described in Section 2.3.6 are not of an appropriate scope or have not
     been granted on terms consistent with those described in the last clause of
     Section 2.3.6, then EndoChem shall facilitate and cooperate with Licensee's
     efforts to seek any legal or equitable recourse available to EndoChem under
     the UC Agreement with respect to such belief, including, without
     limitation, permitting Licensee to seek legal and equitable remedies in
     EndoChem's name at Licensee's expense. EndoChem shall retain the right, at
     its sole discretion, to engage counsel of its own choice in connection with
     any such legal or equitable remedies undertaken by Licensee for the sole
     purpose of monitoring Licensee's efforts to seek such legal or equitable
     remedies.

SECTION 3. DEVELOPMENT.

     3.1 Responsibility. Licensee shall be responsible for, and shall have sole
control over the research and development of the Licensed Products, including,
without limitation,

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providing all funding of such research and development, subject to the terms and
conditions of this Agreement. EndoChem shall not be required to incur any
research or development costs or otherwise conduct research or development
relating to Licensed Products. EndoChem shall not conduct any research or
development relating to Licensed Products without Licensee's prior written
consent, provided, however, that Licensee shall consider in good faith any
proposal by EndoChem to allow EndoChem to perform research and development on
Licensed Products, and provided further that Licensee may withhold its consent
in Licensee's sole discretion.

     3.2 Steering Committee. Licensee shall establish a steering committee
("Steering Committee") which shall include two Licensee representatives and one
representative of EndoChem. Each Party may replace its representatives to the
Steering Committee at any time in its sole discretion. The Steering Committee
shall be responsible for monitoring the overall development of Licensed
Products, but shall have no responsibility over the management or day to day
decisions relating to the development of Licensed Products. All decisions of the
Steering Committee shall require a majority vote. The Steering Committee shall
meet semi-annually at dates and times mutually agreeable to the Parties. Each
meeting shall require a quorum of three members. The Steering Committee may meet
by telephone or videoconference or in person as determined by the members.
Attendance at meetings shall be at the respective expense of each Party. The
Steering Committee shall assure that agendas and minutes are prepared for each
of its meetings.

SECTION 4. DILIGENCE.

     4.1 Diligence. The Licensee, by itself or with or through its Sublicensees
or (with respect to development) Development Partners, upon execution of this
Agreement, will diligently proceed with the development, manufacture and Sale of
Licensed Products and will earnestly and diligently market the same after
execution of this Agreement and in quantities sufficient to meet the market
demands therefor.

     4.2 Regulatory Approvals. The Licensee, by itself or with or through its
Sublicensees or Development Partners, will obtain all necessary Regulatory
Approvals in each country where Licensed Products are manufactured, used, Sold,
offered for Sale or imported. For the purpose of the foregoing sentence, a
Regulatory Approval will be deemed to be necessary only when the relevant
activity could not be conducted legally within the relevant country without
first obtaining such an approval for the purpose of conducting such activity.
For example and without limiting the foregoing, if Licensee manufactures
Licensed Product in a given country but does not Sell such Licensed Product in
such country, then Licensee shall only be required to have obtained those
approvals necessary to conduct such manufacturing activities in such country,
and it shall not be required to obtain Regulatory Approvals required to sell
such Licensed Product legally in such country unless it also Sells Licensed
Products in such country. For clarity, nothing in this Section 4.2 shall expand
Licensee's diligence obligations under this Agreement to require Licensee or its
Sublicensees or Development Partners to obtain Regulatory Approvals in all
countries of the Territory.

     4.3 Diligence Milestones. The Licensee, its Affiliates and/or Sublicensees
or Development Partners will diligently proceed to achieve the following
milestones prior to or on the target date specified below:

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          4.3.1 submit ************* within ******* after the Effective Date;

          4.3.2 submit ************* within ******* after the Effective Date;

          4.3.3 submit an application for marketing approval in the
     ****************** within ******* after the Effective Date;

          4.3.4 achieve the **** within ********* after the Effective Date;

          4.3.5 launch and market ******************* within **** of receiving
     approval for such Licensed Product from the *** (but in any event
     *******************); and

          4.3.6 fill the market demand for Licensed Products following
     commencement of marketing at any time during the exclusive period as
     required under 35 U.S.C. Section 203.

     4.4 Diligence Funding. In addition to the obligations set forth above,
Licensee, or its Sublicensees or Development Partners shall spend an aggregate
of not less than $****** dollars ($******) for the development of Licensed
Products during the first *** years following the Effective Date of this
Agreement.

     4.5 Tolling of Diligence Milestones. In the event that Licensee is unable
to meet any of the deadlines set forth in Section 4.3 for reasons attributable
to safety, efficacy or regulatory agency actions or requirements (including,
without limitation, such actions or requirements affecting dosage methodology,
formulation or recruitment of clinical sites or clinical patients) which actions
or requirements (a) directly cause a delay in the ability to meet the applicable
milestone, and (b) do not result from the failure of Licensee (or its applicable
Sublicensee and/or Development Partner) to diligently proceed with development
of Licensed Products (including failure to diligently design and conduct
reasonable clinical trials and pursue a reasonable regulatory strategy), then
Licensee may extend the time period for required achievement of such relevant
target milestones and all ensuing target milestones for additional *** year
periods (each an "Extension Period(s)") for up to a total of **** years in the
aggregate. For the avoidance of doubt, Licensee may only obtain a total of
******-year extensions hereunder and no specific target milestone may have its
original time period extended more than **** years beyond its original date
(whether such extensions are cause by the direct extension of such target
milestone or by the combined effect of the extension of preceding milestones, or
both). In order to obtain an extension, Licensee shall pay to EndoChem a fee,
which for the first Extension Period shall be $******, for the second Extension
Period shall be $****** and for the third Extension Period shall be $******,
provided that no fee shall be required to be paid by Licensee to extend any
deadline for any Extension Period in the event that the underlying delay is
caused by a change in the applicable laws and regulations governing the
development of Licensed Products that directly affects the target milestone at
issue. No extension hereunder shall be effective

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unless and until the applicable fee, if any, is paid to EndoChem, which shall
remit such fee to UC as required under Section 11.4 of the UC Agreement. In
addition, (y) with respect to any extension for regulatory actions or
requirements, Licensee must provide EndoChem a written plan for addressing the
problems raised by the source of delay and Licensee shall thereafter diligently
pursue such plan until the delayed milestone is achieved; (z) with respect to
the **** Extension Period, EndoChem and/or UC shall have the right to discuss
the reasons for any such **** extension with Licensee to understand Licensee's
plan for pursuing the applicable diligence milestone event associated with such
target date. For the avoidance of doubt and by way of example only, it is
understood that in the event Licensee extends a target milestone for the first
Extension Period, then such target milestone and all ensuing target milestones
are automatically extended in a lock-step fashion for *******. Thereafter,
Licensee may extend the same target milestone and all ensuing target milestones
for up to **** Extension Periods, or Licensee may extend one or more of the
ensuing target milestones (and each target milestone following such extended
target milestone) for up to **** Extension Periods, in all cases up to a maximum
extension for each target milestone of *******.

     4.6 Termination Right. Without limiting any other rights or remedies of
EndoChem hereunder, if the Licensee is unable to perform any of the provisions
set forth in Section 4.3 in spite of the extensions granted pursuant to Section
4.5, then EndoChem shall have the right and option to either terminate this
Agreement or convert the exclusive license granted to the Licensee to a
non-exclusive license in accordance with Section 4.7 below. This right, if
exercised, shall be deemed to modify the rights granted in Article 2 as
necessary to effect EndoChem's decision to reduce the license to a non-exclusive
license.

     4.7 Notice of Deficiency. If EndoChem notifies Licensee that Licensee's
rights under this Agreement will terminate or convert the exclusive license to a
non-exclusive license because UC has elected to so terminate or modify such
rights under the UC Agreement for lack of diligence, EndoChem shall give the
Licensee written notice of the deficiency. The Licensee thereafter has
eighty-five (85) days to cure the deficiency. If (a) EndoChem has not received
written tangible evidence that the deficiency has been cured; or (b) for any
non-monetary default, if such default is not curable within such eighty-five
(85) day period and a written plan for such cure reasonably satisfactory to UC
(which in any event shall provide for the cure to be completed no later than one
hundred seventy (170) days from the original date of EndoChem's notice) along
with written tangible evidence that Licensee has begun to implement such plan
has not been received by EndoChem within such eighty-five (85) day period; or
(c) if a cure plan has been provided pursuant to (b) above, EndoChem has not
received within the aforementioned one hundred seventy (170) day period written
tangible evidence reasonably satisfactory to EndoChem and UC that the deficiency
has been cured, then in each case EndoChem may, at its option, terminate this
Agreement immediately by additional written notice to Licensee, which shall be
effective immediately without the obligation to provide any further notice, or
reduce the exclusive license granted to the Licensee to a non-exclusive license
by giving written notice to the Licensee.

SECTION 5. PROGRESS AND ROYALTY REPORTS

     5.1 Reporting Obligation. Beginning on June 15, 2005, and semi-annually
thereafter, the Licensee will submit to EndoChem a written progress report as
described in Section 5.2 below covering the Licensee's (and any Affiliate's,
Sublicensee's or Development

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Partner's) activities related to the development and testing of all Licensed
Products, the obtaining of the governmental approvals necessary for marketing
and the activities required and undertaken in order to meet the diligence
requirements set forth in Section 4. Progress reports are required for each
Licensed Product until the first Sale or other exploitation of that Licensed
Product occurs in the United States and shall be again required if Sales of such
Licensed Product are suspended or discontinued.

     5.2 Development Report Contents. Progress reports submitted under Section
5.1 shall include, but are not limited to, a detailed summary of the following
topics at a level that enables EndoChem and UC to determine the progress of the
development of Licensed Products and to determine whether or not the Licensee
has met its diligence obligations set forth in Article 4 above:

          5.2.1 summary of work completed with respect to development and
     commercialization of Licensed Products as of the submission date of the
     progress report;

          5.2.2 a description of key scientific discoveries relating to Licensed
     Products or Licensed Methods (or the development or commercialization
     thereof) as of the submission date of the progress report (including
     preclinical analyses performed with respect to the Licensed Products);

          5.2.3 a summary of work in progress with respect to development and
     commercialization of Licensed Products as of the submission date of the
     progress report;

          5.2.4 a current schedule of anticipated events and milestones with
     respect to development and commercialization of Licensed Products,
     including those events and milestones specified in Article 4;

          5.2.5 market plans for introduction of Licensed Products including the
     anticipated and actual market introduction dates of each Licensed Product;

          5.2.6 a description of Sublicensees' and/or Development Partners'
     activities relating to the above items, if there are any Sublicensees or
     Development Partners;

          5.2.7 a summary of resources (dollar value) spent in the reporting
     period with respect to development and commercialization of Licensed
     Products;

          5.2.8 a description of Licensee's progress in developing any New
     Licensed Products elected for commercial development by Licensee pursuant
     to Section 2.3.2 of this Agreement; and

          5.2.9 if sublicenses are granted pursuant to Article 2 of this
     Agreement, the identity and number of all Licensed Products under
     development by each Sublicensee for each Licensed Product in development.

     5.3 Failure to Submit Progress Reports. If the Licensee fails to submit a
timely progress report to EndoChem, then EndoChem will be entitled to terminate
this Agreement if

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such failure is not cured within sixty (60) days of receipt of written notice
from EndoChem of such failure. If either Party terminates this Agreement before
any Licensed Products are Sold or before this Agreement's expiration, then a
final progress report covering the period prior to termination must be submitted
within thirty (30) days of termination or expiration.

     5.4 Business Entity Status. The Licensee has a continuing responsibility to
keep EndoChem informed of the business entity status (small business entity
status or large business entity status as defined by the United States Patent
and Trademark Office) of itself, any Sublicensees and, to the extent relevant
for determination of entity status under applicable law, any of their
Affiliates. The Licensee will notify EndoChem (with a copy to UC) of any change
of its status or that of any Sublicensee or (to the extent applicable) any
Affiliate within thirty (30) days of the change in status.

     5.5 Report of First Sale. The Licensee will report to EndoChem the date of
first Sale of a Licensed Product in each country in its first progress and
royalty reports following such first Sale of a Licensed Product.

     5.6 Royalty Reports. Beginning with the earlier of (i) the first Sale or
other uses of a Licensed Product described in Section 1.23(iii), or (ii) the
first transaction that results in Sublicense Fees accruing to EndoChem, the
Licensee will make quarterly Earned Royalty and Sublicensee Fee reports to
EndoChem on or before each February 15 (for the quarter ending December 31), May
15 (for the quarter ending March 31), August 15 (for the quarter ending June 30)
and November 15 (for the quarter ending September 30) of each year. Each Earned
Royalty and Sublicensee Fee report will cover Licensee's most recently completed
calendar quarter and will, at a minimum, show:

          5.6.1 the gross invoice prices and Net Sales of Licensed Products Sold
     or otherwise exploited as described in the Net Sales definition (itemizing
     the applicable gross proceeds and any deductions therefrom);

          5.6.2 the quantity of each type of Licensed Product Sold or otherwise
     exploited;

          5.6.3 the country in which each Licensed Product was made, used or
     Sold or otherwise exploited;

          5.6.4 the Earned Royalties, in United States dollars, payable with
     respect to Net Sales;

          5.6.5 the Sublicense Fees, in United States dollars, payable with
     respect to Attributed Income;

          5.6.6 the method used to calculate the Earned Royalty, specifying all
     deductions taken and the dollar amount of each such deduction;

          5.6.7 the exchange rates used, if any;

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          5.6.8 the amount of the cash and the amount of the cash equivalent of
     any non-cash consideration including the method used to calculate the
     non-cash consideration; and

          5.6.9 any other information reasonably necessary to confirm Licensee's
     calculation of its financial obligations hereunder.

If no Sales of Licensed Products have been made and no Licensed Products have
been otherwise exploited during any reporting period, then a statement to this
effect must be provided by the Licensee in the immediately subsequent royalty
report.

EndoChem shall be permitted to provide any reports required under this Article 5
to UC for reporting purposes under Article 12 of the UC Agreement, subject to
the confidentiality obligations herein.

SECTION 6. CONSIDERATION.

     6.1 License Fee. Licensee agrees to pay to EndoChem a non-refundable,
non-creditable license fee of $800,000 (the "License Fee"), with $450,000
payable within seven days of the Effective Date, $100,000 payable within seven
(7) days after the twelve (12) month anniversary of the Effective Date, and the
remaining $250,000 payable within seven (7) days after the filing of an IND (or
foreign equivalent) for Commencement of Phase I clinical trials of a Licensed
Product. Any amounts paid by Licensee to EndoChem under that certain Standstill
Agreement between the Parties effective April 28, 2004 (which currently total
$******) shall be credited against the License Fee.

     6.2 Sublicense Consideration.

          6.2.1 The Licensee will pay to EndoChem the following non-refundable
     and non-creditable sublicense fees ("Sublicense Fees"): ***** percent
     (**%) of all Attributed Income.

          6.2.2 The Licensee will also pay to EndoChem, with respect to each
     Sublicensee (other than an Affiliate of Licensee), an earned royalty of
     ***** percent (**%) of the Net Sales of each Licensed Product or Licensed
     Method by such Sublicensee ("Sublicensee Royalty").

     6.3 Milestones. Licensee shall make the following non-refundable,
non-creditable milestone payments to EndoChem within 30 days after the first
achievement of each of the following milestones for each Licensed Product
covered by a Valid Claim in the Licensed Patents being developed by Licensee
within the Field of Use:

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<TABLE>
<CAPTION>
                    MILESTONE EVENT                         PAYMENT
                    ---------------                       ----------
<S>                                                       <C>
Acceptance for ****************                           $  *******
****************
****************



Commencement of the ****************                      $  *******





Commencement of the ****************                      $  *******


Acceptance of ****************                            $  *******

Approval by the ****************                          $  *******

First Regulatory Approval for the                         $  *******
****************
****************
****************


</TABLE>

For purposes of this Article 6, "acceptance of an NDA" means the earliest date
the FDA (or an equivalent foreign regulatory authority) notifies Licensee (or
any Sublicensee or Development Partner or any of their Affiliates) that it has
accepted an NDA submission (or foreign equivalent).

Each milestone payment referred to in this Section 6 shall be made only once
with respect to each Licensed Product and Licensee shall not be required to pay
milestone payments for additional formulations of such Licensed Products which
are developed or commercialized. In the event Licensee ceases development of
another Licensed Product for which milestones payments have been made due to
safety, efficacy, regulatory or manufacturing reasons, and Licensee commences or
continues development of a Licensed Product for the same or similar indications
as the discontinued Licensed Product, then Licensee shall not be obligated to
make any milestone payments to EndoChem with respect to such additional Licensed
Product until such additional Licensed Product achieves milestones which were
not achieved by the discontinued Licensed Product. For clarity, if there are two
(2) different Licensed Products developed for the same indication within the
Field of Use, separate milestone payments shall be payable on each such Licensed
Product as each such Licensed Product achieves a milestone. For the purposes of
this Article 6, a Licensed Product will be deemed different from another
Licensed Product only if a separate NDA or an equivalent application is required

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to obtain marketing approval for such Licensed Product. Furthermore, each such
milestone payment will be payable regardless of whether the applicable milestone
event has been achieved by the Licensee or any Sublicensee or Development
Partner (or any of their respective Affiliates).

     6.4 Royalty.

          6.4.1 During the Royalty Term, Licensee shall pay to EndoChem a
     royalty payment on Licensee's and its Affiliates' Net Sales of each
     Licensed Product or Licensed Method equal to **% of such Net Sales (the
     "Royalty"). Such royalties shall be due and payable without reduction for
     royalties that might be payable by Licensee to Third Parties in respect of
     such Sales, except that Licensee may deduct from any royalties owed for a
     particular Licensed Product, any payments due to Third Parties under
     licenses to a patent that would be infringed by the making, using or
     Selling of the active ingredient included in Licensed Products, but for the
     grant of such license, provided that in no event shall the royalty payable
     to EndoChem be reduced to less than **** percent (**%) of Net Sales of
     Licensed Products or Licensed Methods by the Licensee or any Sublicensee as
     a result of all credits applied under this Agreement and provided further
     that no such credit shall be available with respect to any Combination
     Product to the extent attributable to payments under such Third Party
     license for patent rights that cover the Combination Product Component.

          6.4.2 The Licensee will also pay to EndoChem a minimum annual royalty
     of one hundred thousand dollars ($100,000) for the life of Patent Rights,
     beginning with the year of the first Sale of Licensed Product, which shall
     be deemed to occur in 2012 if it has not actually occurred prior to
     December 31, 2011. The minimum annual royalty will be paid to EndoChem by
     February 28 of each year and will be credited against the Earned Royalty
     due for the calendar year in which the minimum payment was made. However,
     if the year of the first Sale is earlier than December 31, 2011, then the
     Licensee's obligation to pay the minimum annual royalty will be pro-rated
     for the number of months remaining in that calendar year after the month in
     which Sales commence and will be due the following February 28 (along with
     the minimum annual royalty payment for that year), to allow for crediting
     of the pro-rated year's Earned Royalties.

          6.4.3 In the event that any patent, patent application or claim
     thereof included within the Licensed Patents is held invalid in a final
     decision by a court of competent jurisdiction and last resort and from
     which no appeal has or can be taken, then all obligation to pay royalties
     based on that patent or claim or any claim patentably indistinct therefrom
     will cease as of the date of final decision. The Licensee will not,
     however, be relieved from paying any royalties that accrued before such
     final decision and the foregoing shall not limit Licensee's obligation to
     pay the full amount of royalties due hereunder if any other Licensed Patent
     covers the Licensed Products that are Sold.

     6.5 Government Sales. No Earned Royalties will be collected or paid
hereunder on Licensed Products Sold to, or otherwise exploited for, the account
of the United States Government as provided for in the license to the United
States Government. The Licensee and its Sublicensees will reduce the amount
charged for Licensed Products Sold to, or

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otherwise exploited by, the United States Government by an amount equal to the
Earned Royalty for such Licensed Products otherwise due to EndoChem. Such
reduction in Earned Royalties will be in addition to any other reductions in
price required by the United States Government.

     6.6 Payments.

          6.6.1 Earned Royalties are payable on products and methods covered by
     both pending patent applications and issued patents within the Licensed
     Patents. Earned Royalties will accrue on a country-by-country basis until
     the expiration of the last to expire of the Licensed Patents containing a
     Valid Claim in such country, and will be payable to EndoChem when Licensed
     Products are invoiced on a quarterly basis pursuant to Section 6.5.2 below,
     or if not invoiced, when delivered or otherwise used by the Licensee or
     Sublicensee in a manner constituting a Net Sale as described in Article 1.
     For the avoidance of doubt, Licensed Products covered by a Valid Claim of
     the Patent Rights when manufactured shall be treated as Licensed Products
     hereunder for purposes of Earned Royalties, regardless of whether or not
     such Licensed Products are covered by a Valid Claim of the Patent Rights
     when and as Sold. Sublicense Fees with respect to any Attributed Income
     shall accrue to EndoChem within thirty (30) days of the date that such
     Attributed Income is payable by the Licensee.

          6.6.2 The Licensee will pay to EndoChem all Earned Royalties quarterly
     on or before February 25 (for the calendar quarter ending December 31), May
     25 (for the calendar quarter ending March 31), August 25 (for the calendar
     quarter ending June 30) and November 25 (for the calendar quarter ending
     September 30) of each calendar year. Each payment will be for Earned
     Royalties which has accrued within the Licensee's most recently completed
     calendar quarter.

          6.6.3 All payments due to EndoChem under this Agreement shall be made
     in United States dollars and shall be sent by Licensee to EndoChem to the
     attention of "CEO" at the address shown in Section 13.5. The Licensee is
     responsible for paying all bank or other transfer charges. When Licensed
     Products are Sold for monies other than United States dollars, the Earned
     Royalties and other consideration will first be determined in the foreign
     currency of the country in which such Licensed Products were Sold and then
     converted into equivalent United States dollars. For each currency, the
     exchange rate shall equal the daily exchange rate (obtained as described
     below) for the last day of the applicable calendar quarter; each daily
     exchange rate shall be obtained from The Wall Street Journal, Eastern U.S.
     Edition, or, if not so available, an equivalent source of international
     currency exchange rates as otherwise agreed by the Parties in good faith.

          6.6.4 Each Party shall, at the other Party's request, sign license
     and/or royalty agreements directly with the other Party's Affiliates in
     those situations where such agreements would not (i) decrease the amount of
     royalties which would be paid hereunder, net of withholding obligations;
     (ii) otherwise impair EndoChem's ability to seek recourse in the event of
     breach; or (iii) cause EndoChem to breach the UC Agreement. Such agreements
     shall contain the same language as contained herein with appropriate
     changes in parties and territory. No such license and/or royalty agreement
     will relieve Licensee of its obligations hereunder, and Licensee will

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     guarantee the obligations of its Affiliates in any such agreement.
     Royalties received directly from one Party's Affiliates shall be credited
     towards such Party's royalty obligations hereunder. Notwithstanding the
     foregoing, in no event will licenses or agreements executed pursuant to
     this Section 6.6.4 permit any actions not permitted under or that are
     inconsistent with the UC Agreement.

          6.6.5 Sublicense Fees and Earned Royalties on Net Sales of Licensed
     Products and other consideration accrued in any country outside the United
     States may not be reduced by any taxes, fees or other charges imposed by
     the government of such country, except those taxes, fees and charges
     allowed under the provisions of Sections 1.22 or 1.23. Sublicense Fees,
     Earned Royalties and all other payments due EndoChem hereunder do not
     include, and Licensee shall be solely liable for, any taxes not based on
     UC's net income (including, without limitation, any sales, use,
     value-added, property, excise, import or export tax), duties or tariffs
     imposed or levied by any governmental entity on Licensed Products or
     Licensed Methods on any payments payable by Licensee hereunder, or in
     connection with Licensee's activities under this Agreement or the
     performance hereof. Notwithstanding the foregoing, if Licensee is required
     by law to withhold or deduct from any payments to EndoChem as a result of
     the UC Agreement, (a) Licensee may make such required withholding or
     deduction provided that Licensee shall pay such withheld or deducted
     amounts to the appropriate governmental authority and (b) all Sublicense
     Fees, Earned Royalties and all other payments due to EndoChem hereunder
     which are obligated to be paid to UC shall be increased as may be necessary
     so that after Licensee makes all deductions or withholdings that may be
     required by applicable law, EndoChem shall receive amounts which it is
     required to remit to UC equal to the amounts it would have received had no
     such deductions or withholdings been required. If Licensee is required to
     withhold on EndoChem's behalf as a result of EndoChem's obligations to UC
     under the UC Agreement, EndoChem will provide all documentation within its
     control and ability to provide (to the extent not unduly burdensome to do
     so) that is required by any United States government (or foreign
     equivalent) taxing authority or reasonably requested by Licensee to secure
     a reduction in or credit of the applicable withholding taxes. In the event
     EndoChem fails to provide the documentation as required in the foregoing
     sentence after notice from Licensee and an opportunity for EndoChem to cure
     such failure within thirty (30) days of such notice, Licensee may credit
     any additional amounts paid under this Section 6.6.5 on account of a
     withholding obligation (to the extent such additional amounts correspond to
     the reduction or credit that Licensee was attempting to obtain with the
     documentation that EndoChem failed to provide) against future amounts owed
     to EndoChem under this Agreement.

          6.6.6 Notwithstanding the provisions of Article 13.8 if at any time
     legal restrictions prevent the prompt remittance of Earned Royalties or
     other consideration owed to EndoChem by the Licensee with respect to any
     country where a sublicense is issued or a Licensed Product is Sold or
     otherwise used (as described in Paragraph 1.23(iii)), then the Licensee
     shall convert the amount owed to EndoChem which EndoChem is obligated to
     remit to UC under the UC Agreement into United States dollars and will pay
     EndoChem directly from another source of funds in order to remit such
     amount owed to EndoChem.

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          6.6.7 In the event that royalties, fees, reimbursements for Patent
     Prosecution Costs or other monies owed to EndoChem are not received by
     EndoChem when due, the Licensee will pay to EndoChem interest at a rate of
     ten percent (10%) simple interest per annum. Such interest will be
     calculated from the date payment was due until actually received by
     EndoChem. Such accrual of interest will be in addition to and not in lieu
     of, enforcement of any other rights of EndoChem due to such late payment.

     6.7 Books and Records.

          6.7.1 The Licensee will keep accurate books and records showing all
     Licensed Product under development, manufactured, used, offered for Sale,
     imported, Sold and or otherwise exploited; all Net Sales, all Attributed
     Income, and other amounts upon which payments are due hereunder; and all
     sublicenses granted under the terms of this Agreement. Such books and
     records will be preserved for at least five (5) years after the date of the
     payment to which they pertain and will be open to inspection during normal
     business hours (not more frequently than once per year) by an independent
     accounting firm engaged by UC or EndoChem that is reasonably acceptable to
     Licensee to determine the accuracy of amounts paid or payable hereunder and
     of reports for such amounts required to be provided hereunder. Such
     accounting firm shall be bound by terms of confidentiality no less
     restrictive than those set forth herein. In addition, such accounting firm
     may only disclose to UC or EndoChem (a) the amount of any overpayment or
     underpayment if any (or the extent of any failure to deliver accurate
     reports as required hereunder), and (b) any information necessary to
     establish the basis for determining the existence and amount of such
     overpayment or underpayment (or inaccurate report), and may not disclose
     any other information obtained or derived as a result of any such audit.

          6.7.2 EndoChem shall pay the fees and expenses of such examination.
     If, however, an error in royalties or other payments owed to EndoChem of
     more than five percent (5%) of the total amounts due for any year is
     discovered in any examination, then the Licensee shall bear the fees and
     expenses of such examination and shall remit such underpayment to EndoChem
     within thirty (30) days of the examination results.

          6.7.3 Licensee shall require its direct Sublicensees to allow EndoChem
     and/or UC to conduct an audit of such Sublicensee under Sections 6.7.1 and
     6.7.2, as if such direct Sublicensee were Licensee, to determine the
     accuracy of amounts paid or payable hereunder and of reports for such
     amounts required to be provided hereunder. In the event that UC or EndoChem
     wishes to inspect the books and records of a direct Sublicensee such direct
     Sublicensee shall be responsible for gathering and making available all
     necessary books and records of all its further Sublicensees, if any,
     through direct reporting obligations from such further Sublicensees to such
     direct Sublicensee and through exercise of audit rights with such further
     Sublicensees (which will include the right to disclose the audit results to
     UC or EndoChem)), then Licensee shall pay for the costs of **** such
     inspection (with Licensee's costs thereof capped at ******** dollars
     ($******) with any excess payable by UC or EndoChem). In the event that an
     error in payments due to UC of more than **** percent (**%) of the total
     payments due for any year is discovered in any examination

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     of a direct Sublicensee (whether the initial inspection of any subsequent
     inspection), then Licensee shall pay the costs of a follow-up inspection by
     UC or EndoChem, such follow-up inspection not to occur any earlier than one
     (1) year after the predecessor examination conducted under this Agreement.
     For the avoidance of doubt, UC and EndoChem shall not have the right to
     inspect any books and records of Licensee or any Sublicensee that do not
     pertain to the Licensed Products.

          6.7.4 Upon request from UC or EndoChem, Licensee shall provide to UC
     or EndoChem, (and shall require Sublicensees to provide to UC or EndoChem,
     where applicable) reasonable information and documents confirming
     compliance with the applicable sublicensing provisions of Article 2, the
     diligence obligations under Article 4, the reporting obligations under
     Article 5, the use of name related obligations under Article 13 and the
     indemnification obligations under Article 11.

SECTION 7. REPRESENTATIONS AND WARRANTIES.

     7.1 EndoChem Representations. EndoChem represents and warrants that:

          (a) it is the licensee of the Patent Rights under the UC Agreement;

          (b) EndoChem has the right, power and authority to grant to Licensee
     the licenses set forth in this Agreement, and to its knowledge, such
     licenses are free and clear of any liens, security interests, restrictions
     on use or encumbrances of any nature whatsoever;

          (c) EndoChem has not granted, and shall not grant to any Third Party
     or other Affiliate, any rights or licenses, and has not otherwise taken any
     action, that materially conflicts with or adversely affects the rights and
     licenses granted to Licensee under this Agreement;

          (d) to EndoChem's knowledge, UC has maintained the Patent Rights in
     full force and effect, including the payment of maintenance fees;

          (e) to EndoChem's knowledge, the Patent Rights are not involved in any
     court proceeding, arbitration, mediation interference, reissue,
     re-examination or opposition proceeding;

          (f) except for the Letter of Intent between the UC and EndoChem dated
     April 6, 2004, and the Non-Disclosure Agreement between the UC and EndoChem
     dated September 24, 2003, the UC Agreement is the only agreement and
     understanding, written or oral, by and among UC and EndoChem with respect
     to the Patent Rights;

          (g) the UC Agreement will, when executed, be binding as to EndoChem,
     and to EndoChem's knowledge, will be binding as to UC;

          (h) no event has occurred or circumstance exists within EndoChem's
     control that (with or without notice or lapse of time) shall, as of the
     effective date of the UC Agreement, give UC the right to declare a default
     or exercise any remedy

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     under, or to accelerate the maturity or performance of, or payment under,
     or to cancel, terminate or modify, the UC Agreement;

          (i) no notice has been received or given regarding any actual,
     alleged, possible or potential violation or breach of, or default under,
     the UC Agreement as of the Effective Date;

          (j) there are no outstanding renegotiations or attempts to renegotiate
     the UC Agreement;

          (k) there is no action, suit, claim, investigation or proceeding
     pending, or to EndoChem's knowledge, threatened against, by or affecting
     EndoChem, its applicable Affiliates and/or UC, which, if adversely decided,
     might adversely affect: (i) EndoChem's ability to enter into this
     Agreement; (ii) Licensee's rights under this Agreement; or (iii) EndoChem's
     performance of its obligations under this Agreement;

          (l) to EndoChem's knowledge, other than under the UC Agreement or
     under obligations which UC may owe to ****** pursuant to a prior
     license agreement between UC and ****** relating to certain of the
     Patent Rights, there are no royalties or milestone payments which would be
     due and owing to any Third Party under any agreement in effect as of the
     Effective Date relating to the Licensed Patents;

          (m) no regulatory authority in any jurisdiction in the Territory has
     communicated to EndoChem, or to EndoChem's knowledge, to UC or any prior UC
     licensee, any concerns, issues or comments regarding development of any
     Licensed Product; and

          (n) except as expressly set forth in this Agreement, the license to
     Licensee and the associated Invention, Patent Rights, Licensed Products and
     Licensed Methods are provided by EndoChem WITHOUT WARRANTY OF
     MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE OR ANY OTHER WARRANTY
     OF ANY KIND, EXPRESS OR IMPLIED. ENDOCHEM MAKES NO EXPRESS OR IMPLIED
     REPRESENTATION OR WARRANTY THAT THE INVENTION, PATENT RIGHTS, LICENSED
     PRODUCTS OR LICENSED METHODS WILL NOT INFRINGE ANY PATENT, COPYRIGHT,
     TRADEMARK OR OTHER RIGHTS.

     7.2 Mutual Representations. Each of the Parties hereby represents and
warrants to the other Party as follows:

          (a) it has never been, is not currently, and, during the term of this
     Agreement, will not become (i) an individual who has been debarred by the
     United States Food and Drug Administration ("FDA") pursuant to 21 U.S.C.
     Section 335a (a) or (b) ("Debarred Individual") and thereby restricted from
     providing services in any capacity to a person that has an approved or
     pending drug application, or an employer, employee or partner of a Debarred
     Individual, or (ii) a corporation, partnership or association that has been
     debarred by the FDA pursuant to 21 U.S.C. Section 335a (a) or (b)
     ("Debarred Entity") from submitting or assisting in the submission of any
     abbreviated

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     drug application, or an employee, partner, shareholder, member, subsidiary
     or affiliate of a Debarred Entity;

          (b) it is validly existing and in good standing under the laws of the
     state of its incorporation;

          (c) the execution of this Agreement and full and timely performance of
     the covenants, duties and obligations described herein have been duly
     authorized by all necessary corporate action in accordance with all laws;

          (d) it has the full power and authority to execute and deliver this
     Agreement and perform its covenants, duties and obligations described in
     this Agreement;

          (e) with the exception of ongoing patent prosecution matters, there is
     no action, suit, claim, investigation or proceeding pending, or to its
     knowledge, threatened against, by or affecting it or, its applicable
     Affiliates, which, if adversely decided, might adversely affect: (i) such
     Party's ability to enter into this Agreement; (ii) the other Party's rights
     under this Agreement; or (iii) such Party's performance of its obligations
     under this Agreement; and

          (f) this Agreement is a legal and valid obligation binding upon such
     Party and enforceable in accordance with its terms. The execution, delivery
     and performance of this Agreement by such Party does not conflict with any
     agreement, instrument or understanding, oral or written, to which it is a
     party or by which it is bound, nor violate any law or regulation of any
     court, governmental body or administrative or other agency having
     jurisdiction over it.

     7.3 Use of Affiliates. The Parties recognize that each may perform some or
all of its obligations under this Agreement through Affiliates, subject to the
terms and conditions of this Agreement. Each Party shall remain responsible for,
and hereby guarantees, the performance by its Affiliates and shall cause its
Affiliates to comply with the provisions of this Agreement in connection with
such performance. In the event of any dispute arising from the performance by an
Affiliate under this Agreement, the Party having such a dispute may proceed
directly against the other Party, without any obligation to first proceed
against the Affiliate.

SECTION 8. TERM AND TERMINATION.

     8.1 The term of this Agreement shall begin on the Effective Date of this
Agreement and continue until this Agreement is terminated as provided herein.

     8.2 Subject to Licensee's rights under Section 3.1.2 of the UC Agreement,
this Agreement shall terminate automatically upon termination or expiration of
the UC Agreement.

     8.3 If the Licensee fails to perform or violates any material term or
provision of this Agreement, then EndoChem may give written notice of such
default ("Notice of Default") to the Licensee. If the Licensee fails to repair
such default within 45 days for a monetary

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default and 75 days for all other defaults, in each case after the effective
date of such notice, then EndoChem will have the right to immediately terminate
this Agreement and its licenses by providing a written notice of termination
("Notice of Termination") to the Licensee. Notwithstanding the foregoing, in the
event of a non-monetary default that cannot be cured within 75 days of EndoChem
notice, the applicable cure period shall be extended to 160 days from the date
of EndoChem' notice provided that the Licensee provides a reasonable, written
cure plan to EndoChem and diligently works to implement such plan within such
extended cure period. If the applicable default is not cured within such 160 day
period from the date of EndoChem's notice, EndoChem shall have the right to
terminate this Agreement as provided above.

     8.4 Licensee may terminate this Agreement at any time by giving at least 90
days written and unambiguous notice of such termination to EndoChem. Such a
notice shall be accompanied by a statement of the reasons for termination.
Licensee may also terminate its rights under the Licensed Patents on a
country-by-country basis by giving notice in writing to EndoChem.

     8.5 Upon the termination of this Agreement, Licensee shall remain obligated
to provide an accounting for and to pay milestone and other payments and
royalties earned up to the date of the termination.

     8.6 If applicable Patent Rights exist at the time of any making, Sale,
offer for Sale, or import of a Licensed Product, then Earned Royalties shall be
paid at the times provided herein and royalty reports shall be rendered in
connection therewith, notwithstanding the absence of applicable Patent Rights
with respect to such Licensed Product at any later time. Otherwise, no Earned
Royalties shall be paid on the Sales of such product or service. Any fees or
other payments owed to EndoChem at the time of expiration not based on the Sales
of a Licensed Product will be paid to EndoChem at the time such fee or other
payment would have been due had this Agreement not expired.

     8.7 Waiver by either Party of a single breach or default, or a succession
of breaches or defaults, shall not deprive such Party of any right to terminate
this Agreement in the event of any subsequent breach or default.

     8.8 If this Agreement is terminated under Section 8.3 or 8.4, Licensee
shall promptly transfer to EndoChem all Technical Information received from
EndoChem in Licensee's possession relating to Licensed Products. Licensee shall
promptly transfer to EndoChem ownership of any IND, NDA or other regulatory
filing relating to the development or marketing approval of any Licensed Product
and shall, and hereby does, grant to EndoChem an exclusive, worldwide,
sublicensable license under Licensee's interest in any invention, patent
application and/or patent relating to Licensed Products then Controlled by
Licensee or its Affiliates in the applicable country(ies) where Licensee's
rights have been terminated, to make, have made, use, sell, offer for sale or
import Licensed Products. If this Agreement is terminated for cause under
Section 8.3 by EndoChem or 8.4 by Licensee above, then the following shall
apply:

          a. If termination occurs prior to completion of an FDA-approved Phase
     I clinical trial: EndoChem will pay to Licensee **** percent (*%) of
     revenues received from any Third Party with respect to Licensed Products,
     up to an aggregate of ****

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     percent (**%) of the costs incurred by Licensee reported as of the
     termination date in compliance with Section 12.2.7 of the UC Agreement.

          b. If termination occurs following completion of an FDA-approved Phase
     I clinical trial and prior to completion of an FDA-approved Phase II
     clinical trial: EndoChem will pay to Licensee **** percent (**%) of
     revenues received from any Third Party with respect to Licensed Products,
     up to an aggregate of **** percent (**%) of the costs incurred by Licensee
     reported as of the termination date in compliance with Section 12.2.7 of
     the UC Agreement.

          c. If termination occurs following completion of an FDA-approved Phase
     II clinical trial: EndoChem will pay to Licensee **** percent (**%) of
     revenues received from any Third Party with respect to Licensed Products,
     up to an aggregate of **** percent (**%) of the costs incurred by Licensee
     reported as of the termination date in compliance with Section 12.2.7 of
     the UC Agreement.

For purposes of this Section 8.8, the term "completion" shall mean the last
dosing of the last patient in the applicable clinical trial.

     8.9 If this Agreement is terminated under Sections 8.2, 8.3 or 8.4, then
within a period of one hundred and twenty (120) days after the date of
termination, the Licensee, Sublicensees and Development Partners are entitled to
dispose of all previously made or partially made Licensed Product, but no more,
provided that the Sale or use of such Licensed Product is subject to the terms
of this Agreement, including, but not limited to, the rendering of reports and
payment of Earned Royalties and other amounts due. The Licensee, Sublicensees or
Development Partners may not otherwise make, Sell, offer for Sale or import
Licensed Products or practice the Licensed Method after the date of termination.

     8.10 Upon expiration of the term of this Agreement (but not termination
under Section 8.3 or 8.4), in addition to the other rights and obligations of
the Parties pursuant to this Section 8, Licensee shall have a fully paid-up,
perpetual, nonexclusive license to use the Technical Information for Licensed
Product(s) in the Field of Use in the Territory with no obligation of accounting
or otherwise to EndoChem, solely to the extent necessary or useful to research,
develop, and commercialize Licensed Products.

     8.11 Any termination or expiration of this Agreement will not affect the
rights and obligations set forth in Sections 6.2 (solely as to amounts accrued
before the effective date of termination or pursuant to Section 8.9 after
termination), 6.4.2 (solely as to amounts accrued before the effective date of
termination or pursuant to Section 8.9 after termination), 6.6.7, 6.7, and
Articles 1, 8, 9, 10, 11 and 13.

SECTION 9. CONFIDENTIALITY.

     9.1 Except as specifically permitted hereunder, each Party hereby agrees to
hold in confidence and not use on behalf of itself or others, all data, samples,
technical and economic information (including any progress reports, royalty
reports, or the terms hereof), commercialization, clinical and research
strategies and know-how provided to a Party by the other Party (the "Disclosing
Party") for a period of five years from the date of disclosure

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(collectively the "Confidential Information"). Confidential Information of
EndoChem shall not include the Technical Information.

     9.2 The Licensee and EndoChem may use and disclose Confidential Information
they receive pursuant to this Agreement to their employees, agents, consultants,
contractors and, in the case of the Licensee, its Sublicensees, Development
Partners, bona fide potential Sublicensees, investors and professional service
providers who have a need to know such Confidential Information, provided that
such entities are bound by a duty of confidentiality substantially similar to
that provided in this Article 9.

     9.3 The obligations under Sections 9.1 and 9.2 shall not apply to any
"Confidential Information" to the extent such information:

          (i) is or becomes part of the public domain through no fault of the
     non-Disclosing Party or its Affiliates;

          (ii) is obtained after the date hereof by the non-Disclosing Party or
     one of its Affiliates from any Third Party which is lawfully in possession
     of such Confidential Information and not in violation of any contractual or
     legal obligation to the Disclosing Party with respect to such Confidential
     Information;

          (iii) is independently developed by the non-Disclosing Party as shown
     by written records of the non-Disclosing Party;

          (iv) is known to the non-Disclosing Party or one or more of its
     Affiliates prior to disclosure by the Disclosing Party, as evidenced by the
     non-Disclosing Party's written records; and

          (v) is necessary to be disclosed to any governmental authorities or
     pursuant to any regulatory filings, provided that in such case the
     non-Disclosing Party notifies the Disclosing Party reasonably in advance of
     such disclosure and cooperates with the Disclosing Party to minimize the
     scope or content of such disclosure.

     9.4 Licensee shall have sole control, in its sole discretion, over the
publication or dissemination of the results of the development of Licensed
Products. Neither Party shall issue any communications to the general public
regarding the contents of this Agreement without the prior written consent of
the other Party, except to the extent required by any law, rule or regulation,
or advice of independent counsel, and in such event, the Party that is required
to make such disclosure shall use reasonable efforts to provide Licensee with a
copy of such communication at least four (4) business days prior to release and
shall in good faith consider all comments or suggested edits made by Licensee.
The Parties agree to issue a press release regarding the consummation of this
Agreement. Such press release shall be subject to mutual agreement of the
Parties.

     9.5 Upon termination (but not expiration) of this Agreement, the
non-Disclosing Party will destroy or return any of the Disclosing Party's
Confidential Information in its possession within fifteen (15) days following
the termination of this Agreement. The Licensee and EndoChem will provide each
other, within thirty (30) days following termination, with

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written notice that such Confidential Information has been returned or
destroyed. Each Party may, however, retain one copy of such Confidential
Information it received under this Agreement for archival purposes in
non-working files.

     9.6 The obligations of Section 9.1 and 9.3 shall survive the expiration or
termination of this Agreement for a period of five (5) years.

SECTION 10. INTELLECTUAL PROPERTY RIGHTS.

     10.1 Prosecution of Licensed Patents.

          10.1.1 EndoChem shall (and with regard to the Patent Rights shall use
     commercially reasonable efforts to cause UC to) diligently prosecute and
     maintain the United States and foreign patents comprising the Licensed
     Patents using counsel reasonably acceptable to the Licensee and in
     jurisdictions requested by Licensee (where available). Notwithstanding the
     above, in the event Licensee has rejected three (3) counsels with regard to
     the Patent Rights, Licensee acknowledges that UC shall have the right to
     use reasonably qualified counsel of its choice without Licensee's assent as
     to the Patent Rights. Licensee acknowledges that UC's counsel will take
     instructions only from UC and EndoChem's counsel will take instructions
     only from EndoChem. EndoChem will provide the Licensee with copies of all
     relevant documentation with regard to the prosecution and maintenance of
     the Licensed Patents (as to the Patent Rights, to the extent Licensee
     receives such documentation from UC) so that the Licensee will be informed
     of the continuing prosecution and may comment upon such documentation
     sufficiently in advance of any initial deadline for filing a response.
     EndoChem shall ensure that all such comments by Licensee are considered in
     good faith (except that as to Patent Rights, EndoChem shall only be
     obligated to use commercially reasonable efforts to ensure that UC reviews
     such comments) and, where accepted, are incorporated into such filings;
     provided however, that if Licensee has not commented upon such
     documentation in a reasonable time for EndoChem (and, as to the Patent
     Rights, UC) to sufficiently consider Licensee's comments prior to a
     deadline with the relevant government patent office, or EndoChem or UC (as
     to the Patent Rights) must act to preserve the Licensed Patents, EndoChem
     and/or UC will be free to respond without consideration of Licensee's
     comments, if any. Licensee agrees to treat all such documentation as
     Confidential Information of EndoChem.

          10.1.2 EndoChem shall, and with regard to the Patent Rights shall
     request UC to, use reasonable efforts to amend any patent application to
     include claims reasonably requested by the Licensee to protect the Licensed
     Products contemplated to be made, used or Sold, or the Licensed Method to
     be practiced, under this Agreement. EndoChem shall not abandon any patent
     application or patent within the Licensed Patents (but excluding the Patent
     Rights), except for the purpose of filing continuation or
     continuation-in-part applications, without the prior written consent of
     Licensee. With regard to the Patent Rights shall, EndoChem shall request
     that UC shall not, abandon any patent application or patent within the
     Licensed Patents, except for the purpose of filing continuation or
     continuation-in-part applications within the Patent Rights, without prior
     consultation with Licensee.

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          10.1.3 The Licensee may apply for an extension of the term of any
     patent included within the Licensed Patents if reasonable and appropriate
     under the Drug Price Competition and Patent Term Restoration Act of 1984
     and/or European, Japanese and other foreign counterparts of such Law. The
     Licensee shall prepare all documents and EndoChem agrees to execute, or
     request UC to execute, the documents and to take additional action as the
     Licensee reasonably requests in connection therewith. Licensee shall be
     liable for all costs relating to such application.

          10.1.4 The Licensee may request that EndoChem obtain patent protection
     on any Licensed Product or Licensed Method in foreign countries, if
     available and if it so desires (it being recognized that the deadline for
     making such request as to certain countries in which Patent Rights may have
     been sought has passed). The Licensee will notify EndoChem of its decision
     to obtain or maintain foreign patents not less than thirty (30) days prior
     to the deadline for any payment, filing or action to be taken in connection
     therewith with respect to Licensed Patents that are not Patent Rights, and
     ninety-five (95) days with respect to Patent Rights, provided in each case
     that EndoChem (or, as to Patent Rights, UC) has provided reasonable notice
     to Licensee (or, as to Patent Rights, UC) of such impending deadline.
     EndoChem shall be obligated to provide such notice of impending deadline to
     Licensee, provided that as to Patent Rights, the foregoing shall apply only
     if UC has so notified EndoChem. This notice concerning foreign filing must
     be in writing and must identify the countries desired. The absence of such
     a notice from the Licensee to EndoChem will be considered an election not
     to obtain or maintain foreign patent rights with respect to the applicable
     US patent included in the Licensed Patents.

          10.1.5 The Licensee will bear all past and future costs of preparing,
     filing, prosecuting and maintaining all United States and foreign patent
     applications contemplated by this Agreement ("Patent Prosecution Costs"),
     except as otherwise expressly provided in this Section 10.1.5. Patent
     Prosecution Costs billed to EndoChem by UC's counsel (as to Patent Rights)
     or EndoChem's counsel after the Effective Date will be rebilled to the
     Licensee and shall be due within twenty-five (25) days of such rebilling.
     Such Patent Prosecution Costs will include without limitation past patent
     prosecution costs for the Invention claimed in UC file ***** which were
     incurred by UC prior to the Effective Date, and all patent prosecution
     costs that may be incurred for patentability opinions, re-examination,
     re-issue, interferences, oppositions or inventorship determinations.
     Notwithstanding the foregoing, the Parties have agreed that EndoChem will
     bear solely, and QuatRx shall not be obligated to reimburse EndoChem, a
     total of ************ dollars (*****) in past Patent Prosecution Costs that
     UC has billed to EndoChem and EndoChem has paid to UC prior to the
     Effective Date (such amount, the "EndoChem Amount"). If any Patent
     Prosecution Costs in excess of the EndoChem Amount are incurred and billed
     to EndoChem prior to the Effective Date, then QuatRx shall reimburse
     EndoChem any amounts EndoChem pays to UC or directly pay such amount to UC
     within the time required by the UC Agreement, as the Parties may agree.

          10.1.6 EndoChem (or, as to Patent Rights, UC) may file, prosecute or
     maintain patent applications or patents included in the Licensed Patents at
     its own expense in any country in which the Licensee has not elected to
     file, prosecute or maintain

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     patent applications or patents in accordance with this Article 10 and those
     applications, resultant patents and patents will not be subject to this
     Agreement.

     10.2 Ownership of New Inventions.

          10.2.1 Inventorship of any invention that is developed, discovered or
     made by a Party, solely or jointly with the other Party (as applicable, the
     "Inventor") pursuant to work conducted under this Agreement (an
     "Invention") shall be determined in accordance with United States laws of
     inventorship, subject only to the license rights granted under this
     Agreement. Each Party shall promptly notify the other Party if it
     determines that an Invention has been made. EndoChem shall obtain from each
     of its employees, contractors, representatives and agents a written
     obligation to assign to EndoChem all right, title and interest in and to
     all Inventions. The Inventor of such Invention shall be deemed the owner
     thereof.

          10.2.2 With respect to any patent that claims any Invention which is
     owned by a Party hereunder, such Party shall have the right, at its option
     and expense, to prepare, file and prosecute in its own name any patents
     with respect to any such Invention and to maintain any patents issued
     thereon. In connection with any such prosecution efforts, such Party agrees
     to cooperate reasonably with the other Party at such Party's expense in the
     preparation and prosecution of all such patents and in the maintenance of
     any patents issued. This obligation shall survive the expiration or
     termination of this Agreement.

     10.3 Infringement of Licensed Patents. Each of EndoChem and Licensee shall
promptly inform the other in writing of any infringement of Licensed Patents by
a Third Party in the Field of Use of which it has knowledge and shall provide
the other with any available information relating to such infringement (the
"Infringement Notice").

In the event that the infringement is of Licensed Patents that are included in
the Patent Rights, then the following provisions shall apply:

          10.3.1 During the period in which, and in the jurisdiction where, the
     Licensee has exclusive rights under this Agreement, EndoChem shall use
     reasonable efforts to obtain the consent of UC to permit Licensee, on
     behalf of EndoChem, to notify the possible infringer of infringement or put
     such infringer on notice of the existence of the Patent Rights and shall
     confer with Licensee regarding how to proceed if UC does not so consent. If
     the Licensee puts such infringer on notice of the existence of any Patent
     Rights with respect to such infringement without first so obtaining the
     written consent of UC and if a declaratory judgment action is filed by such
     infringer against UC, then Licensee's right to initiate a suit against such
     infringer for infringement under Section 10.3.2 below will terminate
     immediately. Both EndoChem and the Licensee will use their diligent efforts
     to cooperate with each other and with UC to terminate such infringement
     without litigation.

          10.3.2 If infringing activity of potential commercial significance by
     the infringer has not been abated within ninety (90) days following the
     date the Infringement Notice takes effect, then the Licensee may institute
     suit for patent infringement against the infringer. Licensee understands
     that UC may voluntarily join

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     such suit at its own expense, but may not thereafter commence suit against
     the infringer for the acts of infringement that are the subject of the
     Licensee's suit or any judgment rendered in that suit. The Licensee may not
     join EndoChem or UC as a party in a suit initiated by the Licensee without
     EndoChem's and UC's prior written consent unless required to continue such
     suit. If, in a suit initiated by the Licensee, EndoChem or UC is joined,
     then the Licensee will pay any costs incurred by EndoChem or UC arising out
     of such suit, including but not limited to, any legal fees of counsel that
     EndoChem or UC and Licensee mutually agree to retain to represent EndoChem
     or UC in the suit.

          10.3.3 If, within a hundred and twenty (120) days following the date
     the Infringement Notice takes effect, infringing activity of potential
     commercial significance by the infringer has not been abated and if the
     Licensee has not brought suit against the infringer, then EndoChem or UC
     may institute suit for patent infringement against the infringer. If
     EndoChem or UC institutes such suit, then the Licensee may not join such
     suit without EndoChem's or UC's consent and may not thereafter commence
     suit against the infringer for the acts of infringement that are the
     subject of EndoChem's or UC's suit or any judgment rendered in that suit.

          10.3.4 Notwithstanding anything to the contrary in this Agreement, in
     the event that the infringement or potential infringement pertains to an
     issued patent included within the Patent Rights and written notice is given
     under the Drug Price Competition and Patent Term Restoration Act of 1984
     (and/or foreign counterparts of this Law), then the Party in receipt of
     such notice under the Act shall provide the Infringement Notice to the
     other Party and to UC promptly. If the time period is such that the
     Licensee will lose the right to pursue legal remedy for infringement by not
     notifying a Third Party or by not filing suit, the notification period and
     the time period to file suit will be accelerated to within forty-five (45)
     days of the date of such notice to either Party.

          10.3.5 Notwithstanding the foregoing, to the extent Article 23 of the
     UC Agreement prevents EndoChem from granting the rights set forth in this
     Section 10.3 to Licensee, then the Parties shall confer how to proceed
     within the limits of the UC Agreement, which may include without limitation
     EndoChem itself bringing suit, at Licensee's expense, against such
     infringer, provided that Licensee shall have control over the prosecution
     of such suit. Subject to the foregoing sentence, EndoChem shall have the
     right, but not the obligation, to be represented by counsel of EndoChem's
     choice during any such suit or related proceedings.

          10.3.6 Any recovery or settlement received in connection with any suit
     will first be allocated to UC on the one hand and EndoChem and the Licensee
     on the other hand to cover any  litigation  costs each entity  incurred (if
     any). If such recovery is less than the Parties'  total  litigation  costs,
     the  recovery  shall be shared by UC and the Parties in  proportion  to the
     litigation  costs  each  entity  incurred.  In any  suit  initiated  by the
     Licensee, any recovery in excess of litigation costs will be shared between
     Licensee,  EndoChem  and UC as  follows:  (a) for any  recovery  other than
     amounts paid for willful infringement:  (i) UC will receive ***** percent
     (**%) of the recovery if UC was not a party in the  litigation  and did not
     incur any  litigation  costs,  (ii) UC will receive ***** percent (**%) of
     the recovery if UC was a party in the litigation

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     whether joined as a party under the provisions of Section 10.3.2 or
     otherwise, but did not incur any litigation costs, and (iii) UC will
     receive **** percent (**%) of the recovery if UC incurred more than de
     minimis litigation costs in connection with the litigation; and (b) for any
     recovery for willful infringement, UC will receive **** percent (**%) of
     the recovery. After the foregoing allocation to UC is effected, any
     remaining amounts will be split by the Parties such that Licensee retains
     **** percent (**%) of such amount and EndoChem retains **** percent (**%)
     of such remainder. In any suit initiated by EndoChem or UC, any recovery in
     excess of litigation costs will belong to EndoChem and/or UC. The UC,
     EndoChem and Licensee agree to be bound by all determinations of patent
     infringement, validity, and enforceability (but no other issue) resolved by
     any adjudicated judgment in a suit brought in compliance with this Article
     10.

In the event that the infringement is of a Licensed Patent that is not a Patent
Right, then the following provisions shall apply:

          10.3.7 Licensee shall have the first right to prosecute such
     infringers at its own cost and expense. Licensee may for such purposes use
     the name of EndoChem as a party plaintiff. EndoChem shall reasonably
     cooperate with Licensee, at Licensee's expense, in connection therewith,
     and may participate in any such suit at its expense to protect its
     interests, provided that Licensee shall have control over such prosecution.
     Subject to the foregoing sentence, EndoChem shall have the right, but not
     the obligation, to be represented by counsel of EndoChem's choice during
     any such suit or related proceedings.

          10.3.8 If within ninety (90) days after having been notified by
     Licensee of any alleged infringement pursuant to Section 10.3, Licensee has
     been unsuccessful in persuading the alleged infringer to desist and has not
     brought, and is not diligently maintaining an infringement action or if
     Licensee notifies EndoChem at any time prior thereto of its intention not
     to bring suit against any alleged infringer, then EndoChem may, but shall
     not be obligated to, prosecute, at its own expense, any such infringement
     of the Licensed Patents in the Field of Use, provided that Licensee may, at
     Licensee's expense, participate in any such litigation to the extent
     required to protect its rights.

          10.3.9 Any recovery of damages by Licensee for any such suit shall be
     applied first in satisfaction of any unreimbursed expenses and legal fees
     of Licensee relating to the suit or settlement thereof, and next toward
     reimbursement of EndoChem for any litigation costs incurred by EndoChem.
     The balance thereafter remaining from such recovery shall be allocated **%
     to Licensee and **% to EndoChem. No settlement, or consent judgment, or
     other voluntary final disposition of the suit may be entered into without
     the consent of EndoChem, which consent shall not be unreasonably withheld
     or delayed.

          10.3.10 In the event that EndoChem undertakes the enforcement and/or
     defense of the Licensed Patents by litigation or settlement action, any
     recovery of damages by EndoChem shall be allocated **% to EndoChem and **%
     to Licensee. Provided Licensee is not in breach of this Agreement and is
     current in reimbursing EndoChem for all costs and expenses, including
     reasonable attorney fees and legal

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     costs, in connection with such litigation or action, no settlement, or
     consent judgment, or other voluntary final disposition of the suit, which
     may limit Licensee's rights hereunder may be entered into without the
     consent of Licensee, which consent shall not be unreasonably withheld or
     delayed.

          10.3.11 In any infringement suit that either Party may institute to
     enforce the Licensed Patents or in any declaratory Judgment action alleging
     invalidity, unenforceability or non-infringement of any Licensed Patents
     brought against either Party, the other Party hereto agrees, at the request
     and expense of the Party initiating or defending the suit or action, to
     cooperate in all reasonable respects and to have its employees testify when
     requested and to make available relevant records, papers, information
     samples, and specimens.

          10.3.12 In the event any action is brought by a Third Party in a court
     of competent jurisdiction alleging invalidity or unenforceability of, or
     any other material defect in, any of the Licensed Patents other than the
     Patent Rights against Licensee or EndoChem, Licensee shall have the right
     to withhold **** percent (**%) of any payments due hereunder related to
     the applicable Licensed Patents, including, without limitation, any license
     fees, milestone payments and/or royalties accruing after the date of such
     action, until such time as such action shall have been abated or settled,
     as reasonably determined by Licensee. If such action results in the
     relevant Licensed Patents being determined to be valid, enforceable or
     otherwise not defective (as applicable in view of the nature of such
     action), then Licensee shall repay to Endochem any amounts so withheld in
     reasonable installments as the Parties shall mutually agree (with the
     intent being that Licensee shall not be unduly burdened by such repayment
     obligation prior to First Commercial Sale of Licensed Products).
     Additionally, if any such action results in Licensee recovering amounts
     from the Third Party (for example, as a result of a counterclaim of
     infringement by Licensee), then the withheld amounts shall be reimbursed to
     EndoChem out of such recovery if not otherwise previously repaid.

     Each Party will cooperate with the other in litigation proceedings
instituted hereunder but at the expense of the Party who initiated the suit
(unless such suit is being jointly prosecuted by the Parties). Neither Party
shall consent to the entry of any judgment or settle or otherwise compromise any
such action or suit in a way that adversely affects the other Party's
intellectual property rights or its rights or interests with respect to Licensed
Products without such other Party's prior written consent (not to be
unreasonably withheld). Any litigation proceedings will be controlled by the
Party bringing the suit, except that the other Party may retain counsel of its
choice to monitor the proceedings.

SECTION 11. INDEMNIFICATION.

     11.1 EndoChem hereby agrees to defend, indemnify and hold Licensee and its
employees, officers, directors, representatives, subcontractors, agents and
sublicensees harmless from and against any and all costs, expenses (including
reasonable attorneys' fees and amounts paid in settlement), damages and
liabilities claimed by a Third Party ("Claim") resulting directly or indirectly
from (a) the negligence or willful misconduct or breach of this Agreement or any
EndoChem representation or warranty by EndoChem, or its employees,
representatives, subcontractors, agents or sublicensees or (b) the performance
of any

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research or development of Licensed Products by EndoChem to the extent performed
in a negligent manner or with willful misconduct or in violation of any law,
rule or regulation, all to the extent such Claim does not also result from the
negligence or willful misconduct or breach of this Agreement by Licensee or its
employees, representatives, subcontractors, agents or sublicensees. If Licensee,
in its sole discretion, believes that there will be a conflict of interest or it
will not otherwise be adequately represented by counsel chosen by EndoChem to
defend Licensee in accordance with this Section 11.1, then Licensee may retain
counsel of its choice to represent it and EndoChem will pay all reasonable
expenses for such representation.

     11.2 The Licensee shall, and will require its Sublicensees to, indemnify,
hold harmless and defend EndoChem and UC and their respective officers,
directors, shareholders, employees and agents, the sponsors of the research that
led to the Invention, and the inventors of any invention claimed in patents or
patent applications under Licensed Patents (including the Licensed Products and
Licensed Methods contemplated thereunder) and their employers against any and
all Third Party claims, suits, losses, damage, costs, fees and expenses
resulting from, or arising out of, the exercise of the licenses or any
sublicenses granted pursuant to this Agreement except to the extent arising from
EndoChem's breach of this Agreement or its negligence or willful misconduct
(whether committed by affirmative act or by omission). This indemnification will
include, but not be limited to, any product liability. If UC or EndoChem, in its
sole discretion, believes that there will be a conflict of interest or it will
not otherwise be adequately represented by counsel chosen by the Licensee to
defend UC or EndoChem in accordance with this Section 11.2, then UC or EndoChem
may retain counsel of its choice to represent it and the Licensee will pay all
reasonable expenses for such representation. As a condition to being indemnified
hereunder, the Licensee shall have sole control over the defense and settlement
of all claims, and EndoChem and UC must cooperate with Licensee's investigation,
defense and settlement of all claims and shall promptly notify the Licensee of
all claims and threatened claims; provided, however, that in no event shall
Licensee settle any such claims (nor admit wrongdoing or liability on the party
of any indemnitee) without EndoChem's and UC's prior written consent (provided
that EndoChem's consent shall only be required in the event such settlement
admits liability or wrongdoing on the part of EndoChem or contains any admission
of invalidity of a Licensed Patent or any obligation or other admission, such as
an obligation on the part of EndoChem to perform any act or incur any expense
after such settlement is entered).

     11.3 EXCEPT FOR EACH PARTY'S INDEMNIFICATION OBLIGATIONS UNDER THIS ARTICLE
11, NEITHER PARTY WILL BE LIABLE TO THE OTHER PARTY FOR ANY LOST PROFITS, COSTS
OF PROCURING SUBSTITUTE GOODS OR SERVICES, LOST BUSINESS, ENHANCED DAMAGES FOR
INTELLECTUAL PROPERTY INFRINGEMENT OR ANY INDIRECT, INCIDENTAL, CONSEQUENTIAL,
PUNITIVE OR OTHER SPECIAL DAMAGES SUFFERED BY THE OTHER PARTY ARISING OUT OF OR
RELATED TO THIS AGREEMENT FOR ALL CAUSES OF ACTION OF ANY KIND (INCLUDING TORT,
NEGLIGENCE, STRICT LIABILITY AND BREACH OF WARRANTY) EVEN IF SUCH PARTY HAS BEEN
ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. Notwithstanding anything to the
contrary herein, nothing in this Article 11 shall limit EndoChem's right to seek
and recover from Licensee any accrued but unpaid Earned Royalties, Sublicense
Fees or other payments due pursuant to this Agreement.

     11.4 The terms of this Section 11 shall survive the termination or
expiration of this Agreement.

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SECTION 12. INSURANCE.

     12.1 During the term of this Agreement and for three (3) years following
its termination or expiration, each Party, at its sole cost and expense, will
insure its activities in connection with any work performed hereunder and will
obtain and maintain the following insurance (or an equivalent program of self
insurance):

          12.1.1 Comprehensive or Commercial Form General Liability Insurance
     (contractual liability included) with limits as follows:

<TABLE>
<S>                                        <C>
Each Occurrence                            $  500,000
Products/Completed Operations Aggregate    $1,000,000
Personal and Advertising Injury            $  500,000
General Aggregate (commercial form only)   $1,000,000
</TABLE>

          12.1.2 Notwithstanding the above, no later than the earlier of: i)
     sixty (60) days before the anticipated date of market introduction of any
     Licensed Product; or ii) sixty (60) days before the first use of any
     Licensed Product in a human under this Agreement, Licensee, at its sole
     cost and expense, shall insure its activities in connection with the work
     under this Agreement and obtain, keep in force and maintain the following
     insurance (or an equivalent program of self-insurance) during the term of
     this Agreement and for three (3) years following its termination,
     Comprehensive or Commercial Form General Liability Insurance (contractual
     liability included) with limits as follows:

<TABLE>
<S>                                        <C>
Each Occurrence                            $ 5,000,000
Products/Completed Operations Aggregate    $10,000,000
Personal and Advertising Injury            $ 5,000,000
General Aggregate (commercial form only)   $10,000,000
</TABLE>

The coverage and limits referred to in Sections 12.1.1 and 12.1.2 above will not
in any way limit the liability of the Licensee. The Licensee will furnish
EndoChem with certificates of insurance evidencing compliance with all
requirements. Such certificates will:

          12.1.3 Indicate that EndoChem and UC have been endorsed as additional
     insureds under the coverage described above; and

          12.1.4 Include a provision that the coverage will be primary and will
     not participate with, nor will be excess over, any valid and collectable
     insurance or program of self-insurance maintained by EndoChem or UC.
     Licensee will use reasonable efforts to provide thirty (30) days advance
     notice to EndoChem of any modification to Licensee's insurance.

EndoChem will promptly notify the Licensee in writing of any claim or suit
brought against EndoChem or UC for which either EndoChem or UC intends to invoke
the provisions of Section 11.

SECTION 13. MISCELLANEOUS.

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     13.1 Dispute Resolution. In the event of any controversy or claim arising
out of, relating to or in connection with any provision of this Agreement, or
the rights or obligations of the Parties hereunder, the Parties shall try to
settle their differences amicably between themselves. Either Party may initiate
such informal dispute resolution by sending written notice of the dispute to the
other Party, and within ten (10) days after such notice appropriate
representatives of the Parties shall meet for attempted resolution by good faith
negotiations. If such representatives are unable to resolve promptly such
disputed matter within such ten (10) day period, either Party shall have the
right to pursue all available remedies at law or in equity. Notwithstanding the
foregoing, EndoChem shall not be obligated to utilize the foregoing informal
dispute resolution procedures with respect to any controversy or claim regarding
amounts paid or payable by Licensee to EndoChem hereunder.

     13.2 Assignment.

          13.2.1 Affiliates. Either Party may assign any of its rights or
     obligations under this Agreement in any country to any Affiliates;
     provided, however, that such assignment shall not relieve the assigning
     Party of its responsibilities for performance of its obligations under this
     Agreement, and further provided that if a proposed assignment would have an
     adverse financial impact upon the non-assigning Party (e.g., by reason of
     changed tax treatment of payments due under this Agreement), such
     assignment shall be subject to the other Party's prior written consent. If
     EndoChem assigns this Agreement or is acquired by any entity that is then
     developing or commercializing a product for the same indications for which
     Licensee is then developing or commercializing Licensed Products, then
     after the closing of such transaction, QuatRx's obligations under Section
     5.2 shall be modified so that QuatRx shall provide the reports required
     thereunder directly to UC and shall provide to EndoChem or the assignee or
     acquiring entity only a summary report containing information necessary for
     confirming QuatRx's performance of its obligations under Article 4.

          13.2.2 Merger, Acquisition Or Sale Of Assets. Subject to the terms
     hereof, either Party may assign its rights or obligations under this
     Agreement to a non-Affiliate only in connection with a merger or similar
     reorganization or the Sale of all or substantially all of its assets or the
     Sale of all or substantially all of its pharmaceutical and/or healthcare
     assets, or otherwise without the prior written consent of the other Party.
     This Agreement shall survive any such merger or reorganization of either
     Party with or into, or such Sale of assets to, another party and shall be
     fully enforceable against the surviving, consolidated or reorganized entity
     of such merger, consolidation or re-organization and no consent for such
     merger, reorganization or Sale shall be required hereunder.

          13.2.3 Binding Upon Successors And Assigns. This Agreement shall be
     binding upon and inure to the benefit of the successors and permitted
     assigns of the Parties. Any assignment not in accordance with this
     Agreement shall be void and the rights and obligations shall remain in the
     Party that attempted the void assignment.

     13.3 Further Actions. Each Party agrees to execute, acknowledge and deliver
such further instruments, and to do all such other acts, as may be necessary or
appropriate in order to carry out the purposes and intent of this Agreement.

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     13.4 No Trademark Rights. Except as otherwise provided herein, no right,
express or implied, is granted by this Agreement to use in any manner the name
of EndoChem, Licensee or any other trade name or trademark of either Party or
its Affiliates in connection with the performance of this Agreement.

     13.5 Notices. All notices hereunder shall be in writing and shall be deemed
given if delivered personally or by facsimile transmission (receipt verified),
telexed, mailed by registered or certified mail (return receipt requested),
postage prepaid, or sent by express courier service, to the Parties at the
following addresses (or at such other address for a Party as shall be specified
by like notice; provided that notices of a change of address shall be effective
only upon receipt thereof).

     If to Licensee, addressed to:
          QuatRx Pharmaceuticals Company
          777 East Eisenhower Parkway, Suite 100
          Ann Arbor, MI 48108
          Attention: CEO
          Telephone: 734-913-9900
          Telecopy: 734-913-0743

     With a copy to:
          Brinza & Associates
          49697 Leyland
          Novi, MI 48374
          Attention: Jeffery M. Brinza, Esq.
          Telephone: 248-939-3927

     If to EndoChem, addressed to:
          EndoChem, Inc.
          1751 Capistrano Avenue
          Berkeley, CA 94707
          Attention: John Maynard, CFO
          Telephone: 510-524-2684
          Telecopy: 510-524-8206

     13.6 Waiver. Except as specifically provided for herein, the waiver from
time to time by either of the Parties of any of their rights or their failure to
exercise any remedy shall not operate or be construed as a continuing waiver of
same or of any other of such Party's rights or remedies provided in this
Agreement.

     13.7 Severability. If any term, covenant or condition of this Agreement or
the application thereof to any Party or circumstance shall, to any extent, be
held to be invalid or unenforceable, then (i) the remainder of this Agreement,
or the application of such term, covenant or condition to the Parties or under
circumstances other than those as to which it is held invalid or unenforceable,
shall not be affected thereby and each term, covenant or condition of this
Agreement shall be valid and be enforced to the fullest extent permitted by law;
and (ii) the Parties hereto covenant and agree to renegotiate any such term,
covenant or application thereof in good faith in order to provide a reasonably
acceptable alternative to the term, covenant or condition of this Agreement or
the application thereof that is invalid or

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unenforceable, it being the intent of the Parties that the basic purposes of
this Agreement are to be effectuated.

     13.8 Ambiguities. Ambiguities, if any, in this Agreement shall not be
construed against any Party, irrespective of which Party may be deemed to have
authored the ambiguous provision.

     13.9 Governing Law. THIS AGREEMENT WILL BE INTERPRETED AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF CALIFORNIA, excluding any choice of law
rules that would direct the application of the laws of another jurisdiction and
without regard to which Party drafted particular provisions of this Agreement,
but the scope and validity of any patent or patent application will be governed
by the applicable laws of the country of such patent or patent application.

     13.10 Government Approval Or Registration. If this Agreement or any
associated transaction is required by the law of any nation to be either
approved or registered with any governmental agency, the Licensee will assume
all legal obligations to do so. The Licensee will notify EndoChem if it becomes
aware that this Agreement is subject to a United States or foreign government
reporting or approval requirement. The Licensee will make all necessary filings
and pay all costs including fees, penalties and all other out-of-pocket costs
associated with such reporting or approval process.

     13.11 Compliance With Laws. The Licensee, its Sublicensees and Development
Partners shall comply with all applicable international, national, state,
regional and local laws and regulations in performing its obligations hereunder
and in its use, manufacture, Sale or import of the Licensed Products or practice
of the Licensed Method. The Licensee, its Sublicensees and Development Partners
will observe all applicable United States and foreign laws with respect to the
transfer of Licensed Products and related technical data to foreign countries,
including, without limitation and where applicable, the International Traffic in
Arms Regulations (ITAR) and the Export Administration Regulations. The Licensee,
its Sublicensees and Development Partners shall manufacture Licensed Products
and practice the Licensed Method in compliance with applicable government
importation laws and regulations of a particular country for Licensed Products
made outside the particular country in which such Licensed Products are used,
Sold or otherwise exploited. EndoChem shall comply with all laws, rules and
regulations applicable to the performance of its obligations under this
Agreement.

     13.12 Bankruptcy Provision. All rights and licenses granted by EndoChem to
Licensee under or pursuant to this Agreement are, and shall otherwise be deemed
to be, for purposes of Section 365(n) of the U.S. Bankruptcy Code, licenses of
rights to "intellectual property" as defined in Section 101 of the Bankruptcy
Code. The Parties agree that Licensee, as exclusive licensee of such rights
under this Agreement, shall retain and may fully exercise all of its rights and
elections under the Bankruptcy Code. The Parties further agree that, in the
event of the commencement of a bankruptcy proceeding by or against EndoChem
under the Bankruptcy Code, Licensee 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, and same, if not already in its
possession, shall be promptly delivered to Licensee (i) upon such commencement
of a bankruptcy proceeding, unless EndoChem elects to

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continue to perform all of its obligations under this Agreement; or (ii) if not
delivered under (i) above, upon rejection of this Agreement by or on behalf of
EndoChem.

     13.13 Headings. The Section headings contained herein are for the purposes
of convenience only and are not intended to define or limit the contents of said
Sections.

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

     13.15 Entire Agreement. This Agreement and all exhibits attached hereto,
and all documents delivered concurrently herewith, set forth all the covenants,
promises, agreements, warranties, representations, conditions and understandings
between the Parties hereto with respect to the subject matter hereof and
supersede and terminate all prior agreements and understanding between the
Parties as to such subject matter. There are no covenants, promises, agreements,
warranties, representations, conditions or understandings, either oral or
written, between the Parties with respect to such subject matter other than as
set forth herein and therein. No subsequent alteration, amendment, change or
addition to this Agreement shall be binding upon the Parties hereto unless
reduced to writing and signed by the respective authorized officers of the
Parties.

     13.16 Independent Contractors. Each Party acknowledges that neither it nor
any of its employees are employees of the other Party and that neither it nor
any of its employees are eligible to participate in any employee benefit plans
of the other Party. Each Party further acknowledges that neither it nor any of
its employees are eligible to participate in any such benefit plans even if it
is later determined that its or any of its employees' status during the period
of this Agreement was that of an employee of the other Party. In addition, each
Party hereby waives any claim that it may have under the terms of any such
benefit plans or under any law for participation in or benefits under any of the
other Party's benefit plans.

     13.17 Use Of Names. Nothing contained in this Agreement will be construed
as conferring any right to either Party to use in advertising, publicity or
other promotional activities any name, trade name, trademark or other
designation of the other Party (including a contraction, abbreviation or
simulation of any of the foregoing) without the written consent of such other
Party, which consent shall not be unreasonably withheld or delayed; provided,
however, that either Party may use the name of the other Party in any document
required to be filed to obtain regulatory approval or to comply with applicable
laws, rules or regulations.

     13.18 Force Majeure. Except for the Licensee's obligation to make any
payments to EndoChem hereunder (but not excepting payment obligations to the
extent affected by any force majeure event that forces financial institutions to
close), the Parties shall not be responsible for any failure to perform due to
the occurrence of any events beyond their reasonable control which render their
performance impossible or onerous, including, but not limited to: accidents
(environmental, toxic spill, etc.); acts of God; biological or nuclear
incidents; casualties; earthquakes; fires; floods; governmental acts; orders or
restrictions; inability to obtain suitable and sufficient labor, transportation,
fuel and materials; local, national or state emergency; power failure and power
outages; acts of terrorism; strike; and war. Notwithstanding the foregoing,
either Party to this Agreement, will have the right to terminate this Agreement
upon thirty (30) days' prior written notice if either Party is unable to fulfill
its

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obligations under this Agreement due to any of the causes specified in Section
13.16 for a period of one (1) year.

     IN WITNESS WHEREOF, the Parties hereto have duly executed this Exclusive
License Agreement as of the Effective Date.

QUATRX PHARMACEUTICALS COMPANY          ENDOCHEM, INC.


By: /s/ Stuart Dombey                   By: /s/ John Maynard
    ---------------------------------       ------------------------------------
    (Signature)                             (Signature)
    Stuart Domby                            John Maynard
    (Print Name)                            (Print Name)
Title: CSO                              Title: CFO

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