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                                                                   Exhibit 10.10

                  THYMOSIN BETA 4 LICENSE AND SUPPLY AGREEMENT
                                 ("AGREEMENT")

         This Agreement is made and entered into effective as of January 21,
2004 (the "Effective Date"), by and between

         REGENERX BIOPHARMACEUTICALS, INC., a company organized and existing
pursuant to the laws of the State of Delaware, USA, having its principal offices
at 3 Bethesda Metro Center, Suite 700, Bethesda, Maryland, USA (hereinafter
"RegeneRx");

                                      and

         DEFIANTE FARMACEUTICA LDA, a company organized and existing pursuant to
the laws of Portugal recorded with the Register of Commerce of the Free Zone of
Madeira n(degree) 04607/991124, V.A.T. Code n(degree) 511129840, having its
registered offices at Rua Dos Ferreiros 260, 9000 082 Funchal, Madeira, Portugal
(hereinafter "Defiante").

         RegeneRx and Defiante may be alternately referred to as party,
individually, or parties, collectively.

                                    Recitals
                                    --------

         A. RegeneRx has expertise in developing and manufacturing certain
biologically active peptides, including Thymosin Beta 4, for incorporation into
commercial pharmaceutical products;

         B. Defiante has, directly or indirectly, expertise in developing,
distributing and selling a variety of pharmaceutical and dietary products; and

         C. RegeneRx and Defiante desire to enter into an arrangement for the
commercial development, marketing and distribution of Thymosin Beta 4-based
products under the terms and conditions set forth herein.

         NOW, THEREFORE, in consideration of the mutual representations,
covenants and undertakings set forth herein, and other good and valuable
consideration, the receipt and sufficiency of which is hereby acknowledged,
RegeneRx and Defiante agree as follows:

                                   ARTICLE 1
                                   ---------
                                  DEFINITIONS

The following terms, as used in this Agreement, shall have the meanings set
forth in this Article:

         1.1    "AFFILIATE" means any firm or corporation which, directly or
indirectly, through one or more intermediaries, controls, is controlled by, or
is under common control with, a party. "Control" means the legal or beneficial
ownership of fifty percent (50%) or more of the voting or equity interests or
the power or right to direct the management and affairs of the entity's business
(including acting as the general partner of a limited partnership). For the sake
of clarity, any


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Affiliates to which Defiante grants certain rights, as provided hereunder, under
validly executed license agreements, shall have appropriate terms and conditions
and be commensurate with those recited herein, which are related to the
development, marketing and distribution of the Finished Products.


         1.2    "BULK ACTIVE MATERIAL" means a sequence of amino acids primarily
based on the 43 amino acid peptide commonly referred to as Thymosin Beta 4, in
the form of an active ingredient to be utilized as a component in the Finished
Products.

         1.3    "COMMERCIAL MARKETING APPROVAL" means all authorizations,
permissions, applications and/or registrations from the regulatory and/or
governmental health authorities, including but not limited to the European
Medicinal Evaluation Authority ("EMEA") and ICH Guidelines, for each of the
countries in the Territory, which are necessary and required for the
importation, marketing, use, distribution and Sale of the Finished Products
in the Territory.

         1.4    "CUSTOMER" means any wholesaler, hospital or other entity that
obtains the Finished Products as a result of a Sale.

         1.5    "DEFIANTE IMPROVEMENTS" mean any and all enhancements, changes,
alterations or modifications, including but not limited to, new therapeutic
indications, compositions, fragments, isoforms, analogues, synthetic derivatives
and combinations thereof or with other biologically active ingredients,
developed, created or generated, directly or indirectly, by Defiante, its
Affiliates or Sub-Licensees during the Term of this Agreement, related to or
based on the Finished Products, which are the subject of an independent,
stand-alone proprietary interest and which do not incorporate or infringe the
RegeneRx Improvements or Joint Improvements, nor any of RegeneRx's Patents.

         1.6    "DISTRIBUTOR" means any entity authorized by Defiante, its
Affiliates or Sub-Licensees, that under validly executed agreements, which are
commensurate, as appropriate, with the terms and conditions recited herein, that
shall be authorized only to distribute in the Territory the Finished Products as
a result of a Sale to Customers. Defiante, on an annual basis on each
anniversary of the Effective Date, shall provide RegeneRx a list of all
Distributors

         1.7    "DOCUMENTATION" means any and all proprietary and confidential
reports, Specifications, registration material and dossiers resulting from
clinical trials, including associated patient history (where permitted and in
compliance with all local country disclosure laws), toxicological data, any and
all technical data, notices, pre-clinical data, clinical data, CMC (chemistry,
manufacturing, control data), pharmacokinetic and pharmacological test and
analytical data and any orphan drug submissions, applications or designations,
and any other embodiment of technical information, whether in electronic or
tangible form, related to or associated with Defiante Improvements, Joint
Improvements, RegeneRx Improvements, Bulk Active Material or Finished Products.

         1.8    "FIELD OF USE" means the availability and use of the Finished
Products formulated for the prevention and/or treatment of any indication for
external wounds and internal wounds. For the sake of clarity, such indications
shall include, but not be limited to, the gastrointestinal tract and burns; and
shall not include ocular wounds. It is understood that any treatment or use of
the Finished Products may not be incorporated into the form of any type of
cosmetic product. It is


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understood by the parties that no expansion of this Field of Use may occur
without the express authorization of RegeneRx.

         1.9    "FINISHED PRODUCTS" mean any prescription or over-the-counter
pharmaceutical product, or a medical device, in the Field of Use containing the
Bulk Active Material.

         1.10   "KNOW-HOW" means any and all proprietary and confidential
Information, concepts, ideas, alterations, changes, apparatus, devices,
inventions, methods, techniques, processes, formulations, compositions and
technology arising from, associated with, based on or related to Bulk Active
Material and/or RegeneRx Improvements, which are subject to Intellectual
Property interests under Article 7, Section 7.2.

         1.11   "JOINT IMPROVEMENTS" means any and all enhancements, changes,
alterations or modifications, including but not limited to, new therapeutic
indications, compositions, fragments, isoforms, analogues, synthetic derivatives
and combinations thereof or with other biologically active ingredients,
developed, created or generated jointly by RegeneRx and Defiante during the Term
of this Agreement, resulting from or based on the Finished Products, RegeneRx
Improvements and/or Defiante Improvements.

         1.12   "MANUFACTURING APPROVAL" means all authorizations, permissions,
applications and/or registrations from the relevant regulatory and/or local
government health authorities in each of the countries in the Territory, which
are necessary and required for the manufacture of the Bulk Active Material.

         1.13   "MARKETING YEAR" means each calendar year (January 1 -
December 31) during the Term hereof provided that the first Marketing Year shall
begin on the first day of the month during which the Finished Product is first
made commercially available in any country in the Territory and shall end on
December 31 of the following calendar year.

         1.14   "NET SALES" mean the gross receipt of monies from a Customer
attributable to each Sale of the Finished Product minus:

                  (a)  ***;

                  (b)  ***;

                  (c)  ***;

                  (d)  ***;

                  (e)  ***;

                  (f)  ***;

                  (g)  ***; and

                  (h)  ***.


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         1.15   "PATENTS" mean any and all inventions, processes or methods
which are the subject of patent applications under U.S. Patent Laws
(35 U.S. ss. 101 et seq.) or equivalent international patent laws, and the
resulting granted U.S. or foreign patent, including associated Letters Patent,
substitutions, re-examinations, extensions, reissues, continuations,
continuations-in-part, divisionals, Supplemental Protection Certificates (SPC)
or other recognized forms of patent protection, whether U.S. or foreign, issued
therefrom owned or controlled by RegeneRx and relating to Bulk Active Material,
Finished Products, Joint Improvements or RegeneRx Improvements. Patents related
to Bulk Active Material at the Effective Date are recited in Attachment A, which
is made a part hereof by reference. During the Term of this Agreement and in the
event of the occurrence of RegeneRx Improvements or Joint Improvements, which
may be the subject of Patents, such Patents shall be added to Attachment A from
time to time throughout the Term herein.

         1.16   "REGENERX IMPROVEMENTS" mean any and all enhancements, changes,
alterations or modifications, including but not limited to, new therapeutic
indications, compositions, fragments, isoforms, analogues, synthetic derivatives
and combinations thereof or with other biologically active ingredients,
developed, created or generated, directly or indirectly, by RegeneRx during the
Term of this Agreement related to, resulting from, based on or arising from the
Bulk Active Material and/or the Finished Products.

         1.17   "SALE" means the commercial transfer, either directly or
indirectly through a Distributor and/or a Sub-Licensee, as embodied in a
commercial transaction document such as, but not limited to, a vendor agreement,
purchase order, or the like, of one or more units of the Finished Products to a
Customer for monetary consideration. All Sales must be for monetary
consideration and may not be for in-kind consideration. In particular, a Sale is
considered made on the date an invoice is issued by Defiante, Sub-Licensee or
Distributor to Customer for one or more unit quantities of the Finished
Products.

         1.18   "SPECIFICATIONS" mean information that includes, but is not
limited to, physical descriptions, testing methods and expected assay values,
which recite the strict requirements for Bulk Active Material to be incorporated
into the Finished Products as permitted under the Field of Use for the
Territory, which are subject to Commercial Marketing Approval by the relevant
authorities for each country in the Territory. The Specifications may be
modified from time to time by RegeneRx upon reasonable prior notice to Defiante
and subject to approval by the relevant regulatory authorities for Commercial
Marketing Approval for each country in the Territory. It is understood that
additions or modifications to the Specifications may be required by relevant
regulatory authorities for Commercial Marketing Approval for each country in the
Territory from time to time throughout the Term herein. The Specifications in
effect as of the Effective Date are attached as Attachment B, which is made a
part hereof by reference.

         1.19   "SUB-LICENSEES" mean any third party entities, excluding
Defiante's Affiliates, to which Defiante grants certain rights, as authorized
hereunder, under validly executed license agreements, which are commensurate,
as appropriate, with the terms and conditions recited herein, related to the
development, marketing and distribution of the Finished Products. All
Sub-Licensees, and any and all associated license agreements, shall be subject
to the written approval of RegeneRx, which approval shall not be unreasonably
withheld or delayed.

         1.20   "TERRITORY" means the countries listed in Attachment C, which is
made a part hereof by reference.


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         1.21   "TRADEMARK FOR THE FINISHED PRODUCT" means one or more terms,
designs, marks, names or other designations, which will be associated with the
Finished Products, that will be chosen by Defiante in cooperation with RegeneRx
and thereafter, filed and registered, at Defiante's expense, in each country of
the Territory by Defiante in the name of Defiante or its designee. Trademark for
the Finished Product, once determined and registered, will be identified in
Attachment G, which is made a part hereof by reference.

         1.22   "TRADEMARK FOR THE BULK ACTIVE MATERIAL" means one or more
terms, designs, marks, names or other designations, which will be associated
with the Bulk Active Material, that will be chosen by RegeneRx and, at
RegeneRx's discretion, filed and registered, at RegeneRx's expenses, in each
country of the Territory by RegeneRx in the name of RegeneRx or its designee.
Trademark for the Bulk Active Material, once chosen, will be identified in
Attachment F, which is made a part hereof by reference, and any use thereof will
be subject to "The Trademark Style Guide and Requirements," which is attached
hereto and made a part hereof.

         1.23   "VALID CLAIM" means, on a country-by-country basis in the
Territory, a granted claim within the issued Patents, which has not been held
invalid and/or unenforceable in a decision of a patent office, court or other
government agency of competent jurisdiction, unappealable or unappealed within
the time frame allowed for appeal. However, if no challenge to the Patents
occur, the claims in the issued Patents shall be presumed to be Valid Claims.

         1.24   "WARRANTY AND UNDERTAKING" means the document which is executed
between RegeneRx and Sigma-Tau Finanziaria SpA, an Affiliate of Defiante, that
guarantees the performance of and assumes certain of the responsibilities of
Defiante, or its Affiliates, should Defiante, or its Affiliates, breach or fail
to perform under the Agreement. It is understood that such responsibilities
shall not include the requirement by Sigma-Tau Finanziaria SpA to ***. In the
event Sigma-Tau Finanziaria SpA does not *** then this Agreement shall terminate
as provided hereunder, and Sigma-Tau Finanziaria SpA shall assume all
termination obligations and liabilities to which Defiante, or its Affiliates,
would be subject ***. The Warranty and Undertaking is described in Attachment D,
which is made a part hereof by reference.

It is understood that the definitions shall have the same meaning regardless of
whether a term is used in the singular or plural form.


                                   ARTICLE 2
                                   ---------
                     LICENSE GRANTS, RESERVATIONS OF RIGHTS

         2.1    Grant of License to Finished Products. In consideration of the
fees and royalty payments payable hereunder as recited in Article 3, Defiante
agrees to accept from RegeneRx and RegeneRx hereby grants, only in the Territory
under the terms and conditions recited herein and for the Term as specified
herein, to Defiante the sole and exclusive, royalty-bearing, transferable
(subject to authorizations in Section 2.3 herein), sub-licensable (subject to
authorizations in Section 2.4 herein) right in the Field of Use under the
Know-How, the Documentation, the RegeneRx Improvements, Joint Improvements and
the Patents : i) to use Bulk Active Material to produce or have produced
Finished Products only for making Sales in the Field of Use, either directly,
through its Affiliates or through Distributors or Sub-Licensees, in the
Territory; and ii) to use Bulk Active Material to conduct internal research and
development activities relative to and for the benefit of


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making Joint Improvements or Defiante Improvements to Finished Products
(collectively "Finished Products Grant").

         2.2    Grant of License to Trademark for the Bulk Active Material. In
consideration of the fees and royalty payments payable hereunder as recited in
Article 3, Defiante agrees to accept from RegeneRx and RegeneRx hereby grants,
only in the Territory under the terms and conditions recited herein and for the
Term as specified herein, to Defiante a non-exclusive, royalty-bearing,
transferable (subject to authorizations herein), sub-licensable (subject to
authorizations herein) right in the Field of Use to use, copy, publish, display,
distribute and disseminate, on or in any tangible form or electronic media, the
Trademark for the Bulk Active Material only in connection with the Sale of
Finished Products in the Field of Use and associated marketing collaterals and
packaging in accordance with the terms and conditions of the Trademark Style
Guide and Requirements. This grant of license to Trademark for the Bulk Active
Material shall run concurrent with the Finished Products Grant and shall not be
exercised independent of the Finished Products Grant. Any and all uses of the
Trademark for the Bulk Active Material shall be approved, in writing, by
RegeneRx, which approval shall not be unreasonably withheld or delayed
("Trademark for the Bulk Active Material Grant").

         2.3    Right to Transferability. The Finished Products Grant and the
Trademark for the Bulk Active Material Grant are subject to the transfer and
assignability authorizations recited in Article 11, Section 11.3.

         2.4    Right to Sub-License. With respect to the Finished Products
Grant and the Trademark for the Bulk Active Material Grant, RegeneRx authorizes
Defiante to sub-license the rights recited therein to an Affiliate with no prior
approval by RegeneRx and to a Sub-Licensee only in accordance with the
following: Defiante shall be permitted to issue only one (1) sub-license to only
one (1) Sub-Licensee in each country in the Territory, subject to RegeneRx's
prior written approval of an identified Sub-Licensee and the terms and
conditions of the associated sub-license agreement for that Sub-Licensee, which
approval will not be unreasonably withheld or delayed. Defiante shall not grant
any greater rights to any Sub-Licensee than provided under the Finished Products
Grant and the Trademark for the Bulk Active Material Grant. ***. Further, the
issuance of a sub-license shall not relieve Defiante of paying royalties as
specified in Article 3, Section 3.5 for Sales made by any Defiante's Affiliates
and Sub-Licensees, and Defiante shall be responsible for and liable for any
royalty fees due, owing and payable to RegeneRx as a result of Sales made by any
such Affiliates and Sub-Licensees. Defiante, and not any Defiante's Affiliates
or Sub-Licensees shall be responsible for directly paying to RegeneRx the
royalty payments under Article 3, which are due and payable to RegeneRx.
Additionally, RegeneRx may elect, at its discretion and upon prior written
notice to Defiante, to be subrogated to Defiante's rights and claims against
such Defiante's Affiliates or Sub-Licensees in the event Defiante does not use
reasonable efforts to pursue declared breaches by Defiante's Affiliates or
Sub-Licensees of the applicable terms and conditions of this Agreement. Defiante
shall supply RegeneRx with a list of its Affiliates, as each such Affiliate
obtains rights hereunder.

         2.5    No Right to Sub-License to Distributors. Defiante understands
that Sub-Licensees may also be Distributors, however non-Sub-Licensee
Distributors shall not obtain or be granted any rights under the Finished
Products Grant or the Grant of License to Manufacture Bulk Active Material; but
may be granted, commensurate with the rights and obligations hereunder and
associated therewith, certain rights to use and display the Trademark for the
Bulk Active Material.


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         2.6    Grant of License to Manufacture Bulk Active Material. In the
event that RegeneRx cannot provide Bulk Active Material as recited in Article 4,
Section 4.9, only Defiante shall be granted the right only in the Territory,
under the terms and conditions recited herein and for the Term as specified
herein, a non-exclusive, royalty-bearing, non-transferable, non-sub-licensable
(except as subsequently specified herein) right under the Know-How, the
Documentation, the RegeneRx Improvements, the Joint Improvements and the Patents
to practice, use, manufacture or have manufactured the Bulk Active Material only
to produce Finished Products in order to continue the exercise the Finished
Products Grant in Section 2.1. In the event that Defiante exercises the Grant
of License to Manufacture Bulk Active Material, Defiante shall be obligated to
pay under Section 3.5 the royalty payments specified in Article 3,
Section 3.4(b) ("Bulk Active Material Manufacturing Grant"). If Defiante ceases
the exercise of the Bulk Active Material Manufacturing Grant, the royalty
payments due under Section 3.5 shall be readjusted to the percentage recited in
Article 3, Section 3.4(a). The Bulk Active Material Manufacturing Grant is
sub-licensable by Defiante to its Affiliates; further, the Bulk Active Material
Manufacturing Grant is sub-licensable by Defiante either to Sub-Licensees and/or
to third-party manufacturers only upon the express prior written authorization
of RegeneRx, which authorization shall not be unreasonably withheld or delayed.
RegeneRx expressly acknowledges that as of the Effective Date, Defiante has no
manufacturing facility of its own and hence Defiante cannot directly manufacture
the Bulk Active Material.

         2.7    Grant of License to Documentation. In the event Documentation is
generated by either party during the Term of this Agreement, the following
license grants to the Documentation shall apply:

                  (a)  RegeneRx hereby grants for the Term exclusively to
Defiante only in the Territory for the Field of Use, the right to use, copy and
make available, subject to the confidentiality and intellectual property rights
and obligations recited in Article 7, the Documentation of RegeneRx to permit
Defiante to exercise the Finished Products Grant and/or the Bulk Active Material
Manufacturing Grant to meet the Specifications as recited in Article 6, Section
6.11 and to obtain Manufacturing Approvals and/or Commercial Marketing
Approvals, as recited in Articles 4, 5 and 6, respectively ("RegeneRx
Documentation Grant"). The RegeneRx Documentation Grant shall be sub-licensable
only to Defiante's Affiliates; further the RegeneRx Documentation Grant shall be
sub-licensable to RegeneRx approved Sub-Licensees or third-party manufacturers,
which approval shall not be unreasonably withheld or delayed. The Documentation
of RegeneRx shall be deliverable as provided under Article 6, Section 6.6.
Defiante shall not retain any RegeneRx Documentation upon any termination,
whether for convenience or cause, herein, except that Defiante may retain a copy
of such RegeneRx Documentation upon the natural expiration of the Agreement
consistent with the continued desire by Defiante to commercially exploit the
Finished Product as recited in Section 9.4.2, and which will more particularly
be described in a mutually agreeable new Bulk Active Material supply agreement.

                  (b)  Defiante hereby grants to RegeneRx only for the countries
outside the Territory an irrevocable, non-exclusive, transferable,
sub-licensable, royalty-free, fully paid-up, perpetual right to use in any
manner, copy, distribute, disseminate, edit and modify the Documentation of
Defiante for any purpose, whatsoever. The Documentation of Defiante shall be
deliverable as provided under Article 6, Section 6.6.


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         2.8    NIH Reserved Rights. Defiante acknowledges that the U.S.
Government, as a result of funding by the National Institutes of Health, has
retained certain rights and interests in and to certain aspects of the Bulk
Active Material and RegeneRx Improvements as embodied in Documentation, Patents
and Know-How. Defiante acknowledges such U.S. Government's rights and interests
and agrees to, as appropriate, reasonably give assistance to RegeneRx, at
RegeneRx cost and expense, in complying with RegeneRx contractual obligations or
directly comply with the obligations and requirements as set forth and recited
in Attachment E, which is made a part hereof by reference, and understands that
the U.S. Government may have additional rights and interests that shall prevail,
whether or not such rights or interests are recited herein.

         2.9    Grant of License to Defiante Improvements. During the Term of
this Agreement and in the event Defiante, its Affiliates or Sub-Licensees create
Defiante Improvements, Defiante hereby grants to RegeneRx only in the countries
outside the Territory an irrevocable, non-exclusive, transferable,
sub-licensable, perpetual right to practice, use, manufacture, have
manufactured, distribute, disseminate and sell the Defiante Improvements, for
any purposes whatsoever: ***.

         2.10   No Further Licenses. Defiante acknowledges and agrees that no
other rights or interests are granted hereunder to Defiante, or its Affiliates,
other than as specified under this Article 2, and no additional licenses,
express or implied, are granted to Defiante, or its Affiliates, hereunder.

         2.11   Joint Improvements. In the event of the occurrence of Joint
Improvements, RegeneRx shall assume the responsibility and obligation to obtain
appropriate Intellectual Property protection for such Joint Improvement. In the
event RegeneRx does not so assume, Defiante shall be permitted to obtain such
Intellectual Property protection. The parties, regardless of which party obtains
protection, shall split fifty/fifty (50/50) the reasonable prosecution costs
therefor. In the event of any claims of infringement, both parties agree to
defend the claim and split fifty/fifty (50/50) the costs incurred that are
associated therewith. In the event of the occurrence of Joint Improvements: (i)
during the Term of this Agreement, Defiante, its Affiliates and Sub-Licensees
shall only be permitted, free of charge, to use, manufacture and, directly or
indirectly, commercially distribute the Joint Improvements within the Field of
Use within the Territory; (ii) during the Term of this Agreement, RegeneRx shall
only be permitted, free of charge, to use, manufacture and, directly or
indirectly, commercially distribute the Joint Improvements outside the
Territory; and (iii) following the termination of this Agreement under Article
9, RegeneRx and Defiante shall be subject to the terms recited therein with
respect to Joint Improvements. The aforementioned liability for costs shall
survive termination of this Agreement unless otherwise agreed to by the parties.

                                   ARTICLE 3
                                   ---------
             COSTS AND EXPENSES, PAYMENT OBLIGATIONS, AUDIT RIGHTS

         3.1    Manufacturing and Marketing Costs and Expenses. Defiante, its
Affiliates, its Distributors and/or Sub-Licensees shall bear the full costs,
expenses and liabilities for the production, marketing and distribution of
Finished Products for Sale, and the creation, if any, of associated marketing
collaterals, inserts, advisory information or material or the like, including
any translations thereof. Additionally, Defiante, its Affiliates, its
Distributors and/or Sub-Licensees shall bear any and all costs, expenses and
liabilities related to advertising, of whatever nature, for the Finished
Products in each country in the Territory on or in any medium.


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         3.2    Commercial Marketing Approval Costs and Expenses. Defiante shall
bear the full costs, expenses and liabilities associated with obtaining and
maintaining in its own name and/or in the name of its Affiliates or
Sub-licensees (subject to local regulations) all relevant Commercial Marketing
Approvals recited in Articles 5 and 6, respectively, and meeting and complying
with the Specifications. RegeneRx shall reasonably cooperate, at its expense,
and on an "as available basis," in aiding Defiante to obtain Commercial
Marketing Approvals required for any Finished Products for the purpose of Sales
in each country in the Territory.

         3.3    No Customer Obligations. Defiante understands that RegeneRx
shall have no obligations or liabilities to Customers with regard to the
Finished Products, unless otherwise agreed to by the parties. Defiante, however,
shall be fully responsible for providing Customers with Finished Products and
assuming all liabilities, expenses, costs and obligations associated therewith.

         3.4    Royalty Payments for the Exercise of the Grants in Article 2.
All royalty payments or fees payable hereunder shall be payable in U.S. Dollars,
and the royalty payment amounts shall be subject to deduction for withholding or
similar taxes or fees associated therewith. Defiante shall give RegeneRx such
assistance as may be reasonably necessary to enable or assist RegeneRx to claim
exception therefore (under any applicable laws as well as any applicable
treaties or conventions).

                  (a)  In consideration of the exercise of the Finished Products
Grant and the Trademark for the Bulk Active Material Grant and the Documentation
Grant recited in Article 2, Sections 2.1, 2.2 and 2.7, respectively, Defiante
shall be obligated to pay the following royalty: ***.

                  (b)  In the event of the exercise of Bulk Active Material
Manufacturing Grant as permitted under Article 2, Section 2.6, Defiante shall be
obligated to pay ***.

                  (c)  In the event sub-licenses are granted to Sub-Licensees as
permitted under Article 2, Section 2.4, Defiante shall additionally pay ***.

         3.5    Payment Obligations. RegeneRx shall be entitled to receive
royalty fee payments from Defiante that are due and owing as specified in
Sections 3.4(a), (b), and/or (c) above, on a calendar quarterly basis, which
payments shall be due and payable within sixty (60) days after the end of each
calendar quarter - i.e., February 28, May 31, August 31, November 30,
respectively. Following the receipt of any royalty payment by RegeneRx, such
payments shall be nonrefundable for any reason, subject to Section 8.4.

         3.6    Euro Dollar or Other Currency Conversion to U.S. Dollar. Since
all amounts payable hereunder shall be payable in U.S. Dollar, the parties
acknowledge that the following monetary conversion process will occur with
respect to any payment amounts payable hereunder. Defiante shall on each due
date for a payment convert the different currencies into U.S. Dollars in
accordance with the then current conversion rate recited in The Wall Street
Journal on that due and payable date. The total of the foregoing amounts due,
owing and payable shall be paid by Defiante to RegeneRx on the due date as
specified herein.

         3.7    Taxes/Withholding Taxes. RegeneRx shall not be liable to
Defiante or Sub-Licensees for any costs, taxes or fees associated with the Sale
of Finished Products or the payments received as a result of the issuance and
execution of any sub-license. RegeneRx, however, shall be


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solely responsible for any costs, withholding, taxes or other fees associated
with its receipt of royalty, supply prices or other fee payments hereunder. ***.

         3.8    Finished Product Returns or Customer Refunds and Non-Payment.
In the event Finished Products are returned, ***.

         3.9    Fee and Royalty Reports. Defiante shall provide RegeneRx with
Sales reports on a calendar quarterly basis commensurate with the date on which
royalty payments are due and payable, such reports shall include: i) number of
the units of Finished Products that were the subject of Sales; ii) the revenue
received as a result of Sales; iii) any recordation of actual refunds or
credits; iv) any actual received sub-license fees; and v) recalls, if any, and
the reasons therefore. The foregoing shall be maintained for five (5) years or
as required by applicable law, whichever is greater. Following the occurrence of
a first commercial Sale of the Finished Product, Defiante shall provide RegeneRx
with a status report on each report due date. Defiante shall assume the
obligations to obtain the foregoing reports from Sub-Licensees to supplement
Defiante's report to RegeneRx.

         3.10   Sample Units of Finished Products. Defiante and its Affiliates
and Sub-licensees shall be permitted to distribute, without any obligation to
pay royalties, an adequate representative sample of units of the Finished
Products to Distributors and Customers for the purposes of marketing and
promoting the Finished Products. An estimate of such number of sample units will
be recited in the Marketing Plan, as provided under Section 6.1(b).

         3.11   Right to Receive Royalties. Should any other products containing
the Thymosin Beta 4 be sold in any country of the Territory by any other third
parties and should the Sales of the Finished Product be affected by such
competing products, the parties shall meet to discuss in good faith how best to
proceed, ***. Additionally, Defiante shall ensure that any obligations of
Sub-Licensees to pay royalties shall be the responsibility and obligation of
Defiante and that Defiante shall assume the entire liability therefore
consistent with the requirements hereunder.

         3.12   Audit Rights.

                  (a)  RegeneRx, at its discretion, shall be permitted either:
to perform, at its expense, yearly audits of Defiante's records and books
related to the Bulk Active Material and Finished Products provided such audits
are reasonably conducted at Defiante's convenience and during Defiante's regular
business hours; or to request of Defiante an annual certified statement from
Defiante's auditors that all royalty payments and fees due and owing hereunder
have been accounted for under Generally Accepted Accounting Principles or the
equivalent Territory applicable accounting principles or methods. RegeneRx
acknowledges that any information acquired under the audit shall be considered
Information under Article 7, Section 7.1. In the event that a discrepancy arises
between the royalties and fees paid to RegeneRx and Defiante's records and
books, Defiante shall be given thirty (30) days from the receipt of the notice
to either explain such discrepancy and/or remedy such discrepancy, as
appropriate. Further, in the event of a discrepancy of more than five percent
(5%) between the amount owed and the actual amount received by RegeneRx,
Defiante shall reimburse all the actual expenses and costs incurred by RegeneRx
in performing such audit. Additionally, Defiante shall pay RegeneRx interest
charges equal to the prime United States Treasury rate as published in The Wall
Street Journal on the original royalty payment due dates on the delinquent
cumulative sum plus two percent (2%) per annum on all outstanding amounts due
and owing as determined by the foregoing audit.


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                  (b)  RegeneRx shall consider Defiante in material breach of
this Agreement if Defiante fails to pay RegeneRx the required royalty and fee
payments specified hereunder or does not meet its audit obligations as defined
herein provided that Defiante receives written notice of such breach and is
permitted sixty (60) days from the date of the receipt of the notice to cure
such breach, as permitted under Article 9, Section 9.3. The right to audit by
RegeneRx and the obligations hereunder extend to Sub-Licensees.

                                   ARTICLE 4
                                   ---------
                   BULK ACTIVE MATERIAL ORDERS AND DELIVERIES

         4.1    Exclusive Supplier. During the Term of this Agreement, and
subject to Section 4.9 below, RegeneRx, or its designees, shall be the sole and
exclusive source from which Defiante, its Affiliates and/or Sub-Licensees shall
purchase the Bulk Active Material, and Defiante, its Affiliates and/or
Sub-Licensees shall be the sole and exclusive buyer to which RegeneRx, or its
designees, shall sell the Bulk Active Material, except where otherwise
permitted.

         4.2    Issuance of Purchase Orders. During the Term of this Agreement,
and subject to Section 4.9 below, Defiante, its Affiliates and/or its
Sub-Licensees shall exclusively purchase and RegeneRx shall exclusively supply,
all quantities of Bulk Active Material requested by Defiante, its Affiliates
and/or its Sub-Licensees in accordance with the Specifications and as set forth
on written purchase orders placed by Defiante, its Affiliates and/or
Sub-Licensees under this Agreement. Defiante, its Affiliates and/or Sub-Licensee
shall order Bulk Active Material and RegeneRx shall supply the Bulk Active
Material according to the following procedure. ***.

                  (a)  In anticipation of the need to fulfill the requirements
for engaging in initial actual commercial distribution of the Finished Products
for Sale under Articles 5 and 6, respectively, Defiante, its Affiliates and/or
Sub-Licensee shall initially, namely for the *** from the dates specified by
Defiante for engaging in initial commercial availability of the Finished
Products for Sales, issue a purchase order for Defiante's, its Affiliates'
and/or Sub-Licensee's requirements for an initial supply of Bulk Active Material
needed for such initial commercial distribution of the Finished Product for
Sale. RegeneRx shall deliver the amount specified in the purchase order within
*** of the date of receipt of such purchase order by RegeneRx. Upon the date of
issuance of such purchase order by Defiante, its Affiliates and/or Sub-Licensee,
Defiante, its Affiliates and/or Sub-Licensee shall be obligated to pay the
amount due and owing for the Bulk Active Material ordered in the purchase order,
as specified under Section 4.7.

                  (b)  Following the issuance of such initial purchase order as
recited in Section 4.2(a) above, but no later than *** and *** during each
calendar year thereafter, Defiante, its Affiliates and/or Sub-Licensee shall
issue a purchase order for the amount of Bulk Active Material desired for the
*** to ***. RegeneRx shall deliver the amount specified in each such purchase
order within *** of the date of receipt of such purchase order by RegeneRx.
Payment shall be as specified under Section 4.7.

                  (c)  Throughout the Term of this Agreement, each subsequent
issued purchase orders following such initial purchase order as issued under
Section 4.2(a) above shall specify a quantity of Bulk Active Material that shall
not exceed by more than *** the quantity of the previous year's purchase order
quantity, unless otherwise mutually agreed to by the parties.


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         4.3    Purchase Order Precedence. The terms and conditions of any
purchase order shall be superceded by the terms recited in this Agreement, in
the event of any conflicts.

         4.4    Forecasts. Defiante, its Affiliates and/or Sub-Licensee shall be
required to forecast for a twelve (12) month period the quantities of Bulk
Active Material that Defiante, its Affiliates and/or Sub-Licensee desire from
RegeneRx. Once such twelve (12) month forecast is provided, the actual
quantities desired shall thereafter result in the issuance of a purchase order
from Defiante, its Affiliates and/or Sub-Licensee. Such purchase order
specifying the quantity of Bulk Active Material requested shall be issued twelve
(12) months in advance of the specified delivery date as provided under Section
4.2. Defiante, its Affiliates and/or Sub-Licensee will update such twelve (12)
month forecast on a quarter-by-quarter basis.

         4.5    Supply Price.  The supply price for the Bulk Active Material
shall be equal to ***.

         4.6    Delivery Terms. The delivery of quantities of Bulk Active
Material to be sold to Defiante, its Affiliates and/or Sub-Licensees by RegeneRx
shall be CIP Defiante designated location (Incoterms 2000) by a carrier of
RegeneRx's choice, and RegeneRx shall be liable for any loss or damage to the
Bulk Active Material prior to and up to the point of delivery to Defiante's, its
Affiliates' and/or Sub-Licensee's dock, unless RegeneRx and Defiante otherwise
agree in writing. The dates for delivery of Bulk Active Material in the quantity
specified under issued purchase orders shall be twelve (12) months of the date
of receipt of the purchase order by RegeneRx, subject to mutually agreed upon
date adjustments. In the event Bulk Active Material is not delivered to
Defiante, its Affiliates and/or Sub-Licensees by the carrier on the delivery
date specified herein or damaged, prior to delivery, as a result of a shipping
event, RegeneRx, at its expense, shall use all reasonable efforts to promptly
replace and resend the lost or damaged, as a result of shipping, Bulk Active
Material; or, in the event no other quantities of Bulk Active Material are
deliverable by RegeneRx, then RegeneRx shall fully refund any monies paid by
Defiante, its Affiliates and/or Sub-Licensee to RegeneRx for the lost or
damaged, as a result of shipping, Bulk Active Material that was the subject of
that purchase order associated with that shipment and delivery, and the
foregoing shall serve as Defiante's, its Affiliates' and/or Sub-Licensee's
entire remedy for damaged, as a result of shipping, late and/or non-delivered
Bulk Active Material shipped by RegeneRx under a purchase order.

         4.7    Payment Terms. All purchase orders provided by Defiante, its
Affiliates and/or Sub-Licensees to RegeneRx pursuant to this Agreement shall be
paid in U.S. Dollars (based on the conversion rate between the various
currencies and U.S. Dollar as determined by the rate quoted in The Wall Street
Journal on the date that the purchase order was issued by Defiante, its
Affiliates and/or Sub-Licensee) as follows:

                  (a)  ***:

                       (i)  ***; and

                       (ii) ***

                  (b)  ***, and

                  (c)  ***.


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         4.8    Acceptance of Delivery. RegeneRx warrants that the delivered
quantity, as specified in an associated invoice, of Bulk Active Material shall
meet the Specifications as set forth in the Commercial Marketing Approval, as
evidenced by a Certificate of Analysis (a verification of compliance with the
Specifications) that accompanies the delivered quantity of Bulk Active Material.
Defiante, its Affiliates and/or Sub-Licensees shall have thirty (30) days
following delivery of the Bulk Active Material in which to verify that the Bulk
Active Material meets the Specifications, which verification shall not be
unreasonably withheld or delayed. Following the lapse of thirty (30) days, the
delivered Bulk Active Material shall be considered to have been accepted and the
amounts associated with such accepted Bulk Active Material shall be due and
owing as specified in Section 4.7 above. If some or all of the delivered Bulk
Active Material, in Defiante's, its Affiliates' and/or Sub-Licensees' opinion do
not meet the Specifications, RegeneRx and Defiante, its Affiliates and/or
Sub-Licensees shall promptly engage a mutually acceptable third-party facility
that will conduct an independent analysis of the non-conforming Bulk Active
Material to determine compliance with the Specifications. Such independent
analysis is to be performed under "blinded" conditions so as to remove or
prevent any bias on the part of the facility. If the analysis verifies
compliance with the Specifications, then Defiante, its Affiliates and/or
Sub-Licensees shall be liable for the payments due, owing and payable under
Section 4.7 herein, as well as the total cost associated with the engagement of
such facility. If the analysis demonstrates non-compliance with the
Specifications, then Defiante, its Affiliates and/or Sub-Licensees shall return
the non-complying quantities of Bulk Active Material to RegeneRx, at RegeneRx's
expense, and RegeneRx shall, at its option: i) return the monies paid under the
purchase order for those returned lots of Bulk Active Material, or ii) as soon
as possible and no later than forty-five (45) days of the return F.O.B.
RegeneRx's company headquarters of such quantities of Bulk Active Material,
RegeneRx shall deliver new quantities of Bulk Active Material commensurate with
the quantity of units or lots requested under that purchase order which was
non-conforming to the Specifications. RegeneRx shall also assume the total costs
associated with the engagement of the facility. The acceptance process by
Defiante, its Affiliates and/or Sub-Licensees shall be repeated again for the
redelivered quantity as provided for in this Section 4.8. The foregoing and the
remedy recited in this Section 4.9, herein, will serve as the sole and exclusive
remedies for Defiante, its Affiliates and/or its Sub-Licensees for
non-conformance of delivered Bulk Active Material to Specifications

         4.9    Bulk Active Material Manufacturing Grant Exercise Events. The
occurrence of one or more of the following events during the Term shall permit
only Defiante to exercise the Bulk Active Material Manufacturing Grant recited
in Article 2, Section 2.6, such option to be exercised in writing effective
immediately, if:

                  (a)  RegeneRx, or its third-party manufacturer, ***; or

                  (b)  RegeneRx, or its third-party manufacturer, ***; or

                  (c)  RegeneRx, or its third-party manufacturer, ***; or

                  (d)  RegeneRx, or its third-party manufacturer, is unable to
supply Bulk Active Material ***; or


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                  (e)  RegeneRx, or its third-party manufacturer, is unable to
supply Bulk Active Material ***; or

                  (f)  RegeneRx *** unable to supply the Bulk Active Material,
***.

RegeneRx shall *** if, at any time during the Term of this Agreement, RegeneRx,
or its third-party manufacturer, is unable to supply the quantity of Bulk Active
Material *** or if RegeneRx reasonably believes that RegeneRx is not or will not
be reasonably capable of supplying *** of the Bulk Active Material. ***.

         4.10   Applicability to Sub-Licensees and Affiliates. The obligations
or rights, as appropriate and identified in this Article 4, shall also be
applicable to Sub-Licensees and Affiliates.

         4.11   Non-Termination of Agreement. It is acknowledged by the parties
that non-compliance by RegeneRx with any obligation to supply Bulk Active
Material in this entire Article 4 shall not be construed as a breach by RegeneRx
of this Agreement and shall not entitle Defiante to terminate this Agreement for
cause under Section 9.3 ***.

                                   ARTICLE 5
                                   ---------
            CLINICAL TRIALS, FINISHED PRODUCTS, COMMERCIAL MARKETING
                                    APPROVAL

         5.1    U.S. Phase II Clinical Trial Program. Subject to: (i)
notification to Defiante by RegeneRx of the positive results, in terms of
clinical efficacy and safety, of at least one completed phase II clinical trial
of the Bulk Active Material as embodied in a commercially acceptable product
formulation in the U.S., and (ii) the supply, at Defiante's expense, to Defiante
of reasonably sufficient quantities of Bulk Active Material or U.S. finished
product formulation from RegeneRx; Defiante, within *** of the fulfillment
thereof shall initiate or have initiated at least one (1) pivotal phase III
clinical trial in at least one (1) of the Tier 1 countries in the Territory, as
identified in Attachment C. In particular, Defiante shall have initiated the
activities toward the conduct of one (1) pivotal phase III clinical trial in at
least one of the Tier 1 countries as designed, implemented and monitored
consistent with Commercial Marketing Approval requirements associated with such
Tier 1 country. Defiante shall, ***, complete the phase III clinical trial
following the positive phase II clinical trial. In furtherance of the initiation
and completion of such pivotal phase III clinical trials by Defiante, its
Affiliates or its Sub-Licensee, RegeneRx will, at its discretion, and in view of
the development plan under Section 6.1, supply at mutually agreeable reasonable
costs: (i) the U.S. finished product formulation embodying the Bulk Active
Material, as manufactured in the U.S. or the Bulk Active Material, and (ii) the
relevant Documentation in RegeneRx's possession, which RegeneRx has, in its
opinion, determined to be relevant based on the need to obtain Commercial
Marketing Approval for such Tier 1 country. It is understood that such *** may
be adjusted in the event that insufficient quantities of Bulk Active Material or
the U.S. product formulation required for the pivotal phase III clinical trials
are not available from RegeneRx. In the event sufficient quantities of Bulk
Active Material are available for pivotal phase III trials, such trials must be
initiated no later than *** from the completion of the positive phase II
clinical trial(s) described herein. Once sufficient quantities of Bulk Active
Material or U.S. finished product formulation are available from RegeneRx and
delivery of such Bulk Active Material (as provided under Article 4) or U.S.
finished product formulation occurs, Defiante shall promptly initiate the
pivotal phase III clinical trial. If Defiante cannot obtain the sufficient
quantities of Bulk Active Materials or U.S.


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finished product formulation for the pivotal phase III clinical trial from
RegeneRx as requested *** . If Defiante does not initiate the pivotal phase III
clinical trial, as provided above, Defiante shall alternatively, at its option:
i) pay to RegeneRx in U.S. Dollars via wire transfer on the date that such
pivotal phase III clinical trial should have been initiated, five million U.S.
Dollars (US$5,000,000) and this Agreement shall continue in full force and
effect; OR ii) Defiante may decide to terminate this Agreement as recited under
Article 9, Section 9.2, and meet the obligations recited under Section 9.4. ***.

         5.2    Other Clinical Trials. Defiante may perform other pre-clinical
and clinical trials in the Territory within the Field of Use with respect to the
Finished Products.

         5.3    Clinical Trials/Access to Documentation. RegeneRx shall keep
Defiante or its designated Affiliates and/or Sub-Licensees timely informed of
the progress of phase II clinical trials of the Bulk Active Material as embodied
in a commercially acceptable product formulation in the U.S. Defiante shall keep
RegeneRx timely informed of the progress of any and all clinical trials
involving Finished Products and shall provide RegeneRx with quarterly summary
reports of the results of those trials or, in the alternative, discuss the same
in the Management Meetings, as provided in Section 6.9. Defiante shall give
RegeneRx access to all Documentation, including the clinical reports and patient
histories (as permitted by applicable local country law in the Territories)
concerning all clinical trials, upon request by RegeneRx.

         5.4    Support of Registration for New Indications. Defiante
acknowledges that the Field of Use specifies the scope of authorized
indications, as typically and customarily defined in the industry. Defiante may
pursue new indications in the Field of Use from time to time, shall be obligated
to inform RegeneRx of such new indications that Defiante pursues, and shall
provide Documentation reflecting same. In the event such indications are being
pursued, RegeneRx will use reasonable efforts to support Defiante's efforts and
Defiante shall use reasonable efforts to pursue such indications as rapidly as
practicable, including the filing of any additional registrations for Commercial
Marketing Approval.

         5.5    Commercial Marketing Applications. As soon as practicable
following the successful conclusion of the positive pivotal phase III clinical
trial contemplated in Section 5.1, Defiante shall prepare and file registration
applications for Commercial Marketing Approval in accordance with the
performance objectives recited in Article 6 for use and Sale of Finished
Products within the Field of Use for the Territory. Defiante shall not be
responsible for non-fulfillment of such obligation due to reasons beyond its
control and/or due to reasons which are non-curable, as defined as a force
majeure in Article 11, Section 11.11.

         5.6    Information to RegeneRx. Defiante shall inform RegeneRx
immediately of the approval of any registration applications and/or a ruling of
any restrictions associated with registrations regarding Commercial Marketing
Approval for Finished Products, including pricing recommendations or
requirements of Finished Products and reimbursement criteria, if applicable. Any
such marketing approvals, restrictions and reimbursement criteria shall be
considered Documentation and shall be subject to use by RegeneRx as provided
under Article 2, Section 2.7(b).

         5.7    Registrations. Defiante, its Affiliates and/or Sub-Licensees
agrees to register this Agreement and any related sub-license agreement with any
foreign governmental agency within the Territory which requires such
registration with any Commercial Marketing Approval authority


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and/or Manufacturing Approval authority; and Defiante, its Affiliates and/or
Sub-Licensees shall pay all costs and fees in connection therewith.

         5.8    Duty to Maintain Authorizations. Defiante, its Affiliates and/or
Sub-Licensees shall use, during the Term, its commercially reasonable efforts to
obtain and maintain Commercial Marketing Approvals and any other registrations
obtained for each country in the Territory in the name of Defiante, its
Affiliates and/or Sub-Licensees subject to local regulations.

         5.9    Diligence. Defiante, its Affiliates and/or Sub-Licensees, as
appropriate, and RegeneRx shall perform their respective obligations under this
Article 5 using reasonable, good faith and diligent efforts.

                                   ARTICLE 6
                                   ---------
            RESEARCH AND DEVELOPMENT, MARKETING AND SALE OF FINISHED
                                    PRODUCTS

         6.1    (a)  Research and Development Plan. As soon as practicable after
the Effective Date but no later than June 30, 2004, Defiante shall deliver or
have delivered to RegeneRx a written tentative outline of the activities that
Defiante plans to undertake with respect to the research and development
activities and clinical trials associated with the development of any Finished
Products, and in anticipation of the Sales and eventual production of any
Finished Products, whenever appropriate. The outline shall be updated annually
on the Effective Date during the Term or at such other times, such as but not
limited to the Management Meetings under Section 6.9, as the parties may
mutually agree.

                (b)  Marketing Plan. Within three (3) months before any expected
date of launch or commercial availability to Customers of the Finished Products
in any country in the Territory, Defiante, its Affiliates and/or Sub-Licensee
shall deliver to RegeneRx a written marketing plan ("Marketing Plan") for each
country detailing Defiante's, its Affiliates' and/or Sub-Licensee's, as the case
may be, plans for marketing, distributing and selling the Finished Products in
that country in the Territory during the next twelve (12) month period following
the actual date of commercial availability of the Finished Product. Thereafter,
Defiante, its Affiliates and/or Sub-Licensee shall deliver to RegeneRx written
updates to each of the initial Marketing Plans for each country at twelve (12)
months after the first year of initial commercial availability of the Finished
Products; and thereafter, an updated Marketing Plan shall be deliverable to
RegeneRx on an annual basis. Each such Marketing Plan shall contain a detailed
plan for the reasonable and diligent commercialization of the Finished Products
in each country in the Territory that has secured Commercial Marketing Approval,
including (i) a product pricing strategy; and (ii) a marketing and sales
strategy including anticipated pre- and post-commercial availability sample
needs, the number of units or samples. It is understood that the distribution of
sample Finished Products, as specified in each Marketing Plan and for which
Defiante receives no payment, shall not be subject to the payment of royalties.
The parties shall meet and confer on each Marketing Plan during the Management
Meetings, as provided under Section 6.9. Defiante, its Affiliates and/or
Sub-Licensee shall supply, at no cost, to RegeneRx a reasonable quantity of pre-
and post-launch sample units of Finished Products, as made available for each
country in the Territory. Each such Marketing Plan shall also give a status
report as to Defiante's, its Affiliates' and/or Sub-Licensee's success (or lack
of success) in implementing the prior year's Marketing Plan for a particular
country. Defiante, its Affiliates and/or Sub-Licensees


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shall actively market the Finished Products in the Territory in accordance with
the terms of the Marketing Plan for that country and pursuant to the
requirements under this Agreement.

         6.2    Commercially Reasonable Efforts. Defiante, its Affiliates and/or
Sub-Licensees shall use commercially reasonable efforts commensurate with the
terms recited herein: (i) to, as promptly as is commercially feasible, obtain
and maintain all necessary Commercial Marketing Approvals for the Sale of the
Finished Products in the Territory; (ii) to make Sales of Finished Products in
accordance with the performance criteria recited in Article 6, Section 6.4 of
such Finished Products in the countries in the Territory; and (iii) to stimulate
and increase interest in the Finished Products in the Territory.

         6.3    No Competition. Subject to applicable laws, Defiante, its
Affiliates, Distributors and Sub-Licensees shall not sell or distribute during
the Term of this Agreement and for nine (9) months following the termination of
this Agreement under Section 9.2, any product containing Thymosin Beta 4, which
is the same or substantially equivalent in the treatment to or indications for
the Finished Products without prior approval of RegeneRx. At all times, this
provision will be subject to applicable local country and EU anti-trust and fair
competition laws and regulations, and any and all applicable laws related to the
commercial activities of pharmaceuticals or other commodity, mass-market
prescription drugs.

         6.4    Performance Obligations. To maintain this Agreement, in whole or
in partial force, Defiante shall establish a date on which to file the first
commercial marketing approval in the Territory according to the following
provisions. ***

                  (a)  "Tier 1" Countries of the Territory as Set Forth in
Attachment C. ***.

                  (b)  "Tier 2" Countries of the Territory as Set Forth in
Attachment C. ***.

                  (c)  "Tier 3" Countries of the Territory as Set Forth in
Attachment C. ***.

                  (d)  ***.

                  (e)  In the event Defiante establishes no dates and/or that no

filings occur according to the dates established by Defiante or subsequently
reviewed by the parties, RegeneRx shall be entitled to terminate this Agreement
for breach under Article 9. In the event some of the foregoing filings in (a),
(b) or (c), respectively, do not occur, RegeneRx, at its discretion, may
eliminate the non-filed countries from the Territory that comprise Tier 1, Tier
2 and/or Tier 3, as applicable, and as such, the Tier 1, Tier 2 or Tier 3
countries that have no filings shall be eliminated from the Territory on the
date that such filings should have been completed, as reflected by amendment to
this Agreement. Additionally, if Commercial Marketing Approval is not
maintained, once obtained in a country in the Territory, for *** or are
withdrawn or suspended by regulatory authorities for *** then such country may,
at RegeneRx's discretion, be eliminated from the Territory. If no Tier 1
Commercial Marketing Approval occur as provided herein, then RegeneRx may, at
its option, terminate this Agreement without further liability or responsibility
hereunder, except for those obligations which survive hereunder.


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         6.5    Minimum Sales.

                (a)  Defiante undertakes to achieve during the first *** after
the launch of the Finished Products in the majority of the Tier 1 countries
certain amounts of minimum Sales as follows, subject to: i) the occurrence of an
event that is beyond the reasonable control of both parties that prevents the
availability of Bulk Active Material or of the Finished Product for a
significant period of time of at least *** and/or ii) ***. Following the
occurrence of Tier 1 country conditions as recited in Sections 6.4(a) and (b),
the royalty payment payable under Article 3 shall be based on the following on a
per country basis:

                  (i)   Marketing Year 1 - ***;

                  (ii)  Marketing Year 2 - ***;

                  (iii) Marketing Year 3 and beyond - ***.

                (b)  Following the occurrence of Tier 2 country conditions as
recited in Section 6.4(b) and (c), the royalty payment payable under Article 3
shall be based on the following on a per country basis:

                  (i)   Marketing Year 1 - ***;

                  (ii)  Marketing Year 2 - ***;

                  (iii) Marketing Year 3 and beyond - ***.

                (c)  Following the occurrence of Tier 3 country conditions as
recited in Section 6.4(c), the royalty payment target payable under Article 3
shall be based on the following on a per country basis:

                  (i)   Marketing Year 1 - ***;

                  (ii)  Marketing Year 2 - ***;

                  (iii) Marketing Year 3 and beyond - ***.

                (d)  In all cases for the determination of minimum Sales ***

                  (i)   ***;

                  (ii)  ***;

                  (iii) ***;

                  (iv)  ***;

                  (v)   ***, and


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                  (vi)  ***.

***.

         6.6    Documentation Deliverables.

                (a)  In the event Defiante, its Affiliates and/or Sub-Licensees
generates or obtains, during the Term, any Documentation relative to Finished
Products or Bulk Active Material, Defiante, its Affiliates and/or Sub-Licensees
shall promptly deliver copies of any and all Documentation to RegeneRx. In the
event RegeneRx has in its possession, as of the Effective Date and during the
Term, Documentation that RegeneRx determines that Defiante, its Affiliates
and/or Sub-Licensees require or would aid Defiante, its Affiliates and/or
Sub-Licensees, in obtaining and maintaining Commercial Marketing Approval or in
conducting clinical studies as a result of access to and use of the
Documentation, RegeneRx shall promptly provide such Documentation to Defiante,
its Affiliates and/or Sub-Licensees. The Documentation of each party shall be
considered Information, as subsequently defined. Additionally, certain
Documentation may be subject to country laws and regulations, including patient
privacy laws, relative to the release and use thereof, and, in such event, such
Documentation may be withheld from a party unless appropriate approvals can be
obtained for release.

                  (b)  Within a reasonable period of time following the
conclusion of the positive phase II clinical trial and in anticipation of the
conduct of a pivotal phase III trial and subject to Section 5.1, RegeneRx shall
deliver, at its fully allocated cost, and at the request of Defiante, sample
quantities of Bulk Active Material for the purposes of conducting the pivotal
phase III clinical testing. RegeneRx shall not be considered to be in breach of
this Agreement if RegeneRx does not deliver the sample quantities requested or
delivers less than the sample quantities requested.

                 (c)  During the Term of this Agreement, RegeneRx shall promptly
inform Defiante of any RegeneRx Improvements and/or Documentation that RegeneRx
has developed. RegeneRx Improvements shall be embodied in or incorporated into
the Finished Products only as provided under Article 6, Section 6.8. In the
event the conditions recited in Section 6.8 do not occur regarding the
embodiment or incorporation of RegeneRx Improvements into the Finished Products,
then no RegeneRx Improvements shall be incorporated unless such RegeneRx
Improvements are necessary for compliance with the Specifications or Commercial
Marketing Approval. The use of the RegeneRx Improvements shall be governed by
the Finished Products Grant and Bulk Active Material Manufacturing Grant recited
in Article 2, Section 2.6.

                 (d)  During the Term of this Agreement, Defiante shall promptly
inform RegeneRx of any Defiante Improvements. Such Defiante Improvements shall
be governed by the Defiante Improvement Grant in Article 2, Section 2.9.
Defiante Improvements shall be embodied in or incorporated into the Finished
Products as recited in Section 6.8. If no mutual agreement occurs, such Defiante
Improvements shall not be incorporated into the Finished Products unless such
Defiante Improvements are necessary for compliance with the Specifications or
Commercial Marketing Approvals.

         6.7    Sample Finished Products Testing. During the Term, Defiante
shall supply, at no charge, to RegeneRx, within seven (7) days of RegeneRx's
request, a small representative sample quantity of units of Finished Products
for the purposes of internal use and evaluation by RegeneRx.


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Upon Defiante's request, RegeneRx shall inform Defiante of its use and
evaluation findings. Such findings shall be considered Information to RegeneRx.
The foregoing shall be applicable to Sub-Licensees.

         6.8    RegeneRx Improvements/Defiante Improvements/Joint Improvements
Incorporation Authorizations.

                  (a)  In the event that Defiante desires to use or incorporate
Joint Improvements, RegeneRx Improvements or Defiante Improvements in the Bulk
Active Material and/or Finished Products, Defiante is free to do so except in
the case where such Joint Improvements, RegeneRx Improvements or Defiante
Improvements constitute substantive changes to the Bulk Active Material and/or
Finished Products. Substantive changes shall be interpreted to include any and
all changes that cause non-compliance with the Specifications, or cause
non-compliance with the Commercial Marketing Approvals required for the Finished
Products. In the case of substantive changes, both parties must review and
mutually approve all such changes prior to such changes being incorporated into
the Finished Products. In the event no mutual agreement is reached, the
provisions of Section 6.8(c) shall govern. Defiante shall be considered in
breach of this Agreement if Defiante incorporates into the Bulk Active Material
and/or Finished Products any substantive changes relative to Joint Improvements,
RegeneRx Improvements or Defiante Improvements without the mutual agreement of
the parties hereto. If both parties mutually agree that such Bulk Active
Material and/or Finished Products, incorporating Joint Improvements, RegeneRx
Improvements or Defiante Improvements, comply with the Specifications and
Commercial Marketing Approval, as the case may be, Defiante may begin production
manufacturing of such Finished Products for Sales to Customers.

                  (b)  Prior to engaging in Sales of Finished Products
incorporating Joint Improvements, RegeneRx Improvements or Defiante
Improvements, Defiante shall supply to RegeneRx, at no charge, at least a
representative number of sample quantities of units of Finished Products using
or incorporating such Joint Improvements, RegeneRx Improvements or Defiante
Improvements for the purposes of internal evaluation and comment, which results
will be shared with Defiante. Such results shall be considered RegeneRx
Information.

                 (c)  In the event the parties fail to reach mutual agreement on
incorporating substantive changes relative to Joint Improvements, RegeneRx
Improvements or Defiante Improvements into the Finished Products, such Defiante
Improvements or RegeneRx Improvements shall not incorporated into the Finished
Products by Defiante.

         6.9    Management Meetings. During the first year of the Term of this
Agreement, the parties shall meet at a time and place mutually agreeable to both
parties within but no later than six (6) months following the Effective Date of
this Agreement, and thereafter no less than and every twelve (12) months to
review research and development, clinical trials, proposed and actual Joint
Improvements, RegeneRx Improvements and Defiante Improvements and to exchange
Information, data and Documentation that may be relevant to the
commercialization of the Bulk Active Material and any advances on the Finished
Products; including, but not limited to, a review of pending Commercial
Marketing Approvals for Finished Products as well as marketing collaterals and
projected Sales in a country in the Territory. Defiante shall also provide at
each Management Meeting, as recited in Section 6.1, and when applicable, reports
which review the commercialization activities pursued by Defiante hereunder; a
review of Defiante's efforts to reduce to practice and to


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commercialize the Finished Products; pending Commercial Marketing Approvals, if
any, for Finished Products; expected market price and reimbursement, where
applicable; marketing collaterals; projected Sales for each country in the
Territory; and the actual use of the Finished Products by Customers. The above
is applicable to Sub-Licensees, as appropriate. The foregoing shall be
considered Information.

         6.10   Finished Products Marketing Collateral. RegeneRx shall be
permitted to review and comment on Finished Products marketing collaterals and
all associated forms, including electronic expressions, of Customer information,
including but not limited to, Finished Products' inserts and directions. All
such marketing collaterals shall conform to the requirements specified by the
appropriate authorities in each country in the Territory responsible for
Commercial Marketing Approval and be consistent with the Specifications required
for each country in the Territory in the Field of Use, and shall be consistent
with the requirements, expectations and quality associated with the standards
that are typical and customary in the industry. Defiante shall promptly provide
RegeneRx copies of the foregoing and Defiante shall ensure that the marketing
collaterals are legally sufficient in each country in the Territory for the
Field of Use.

         6.11   Requirement for the Bulk Active Material to Conform to
Specifications. During the Term, RegeneRx shall strictly comply with the
requirements recited in the Specifications consistent with Commercial Marketing
Approval for each country in the Territory. Additionally, Defiante, at its sole
expense, shall be permitted, upon mutually agreeable times, to visit RegeneRx's
facility, or such other facility, as is under control of RegeneRx for the
purposes of Bulk Active Material manufacture, to observe the manufacture of Bulk
Active Material. If RegeneRx fails to comply with the Specifications as set
forth in the Commercial Marketing Approval, RegeneRx shall use all good faith
and reasonable measures to promptly bring into compliance the Specifications
with such Commercial Marketing Approval so that Defiante can comply with the
Commercial Marketing Approval. RegeneRx, however, shall not alter, change,
modify, revise, update or, in any way, vary the Specifications without
previously notifying and obtaining the approval of Defiante, which approval
shall not be unreasonably withheld or delayed. Thereafter, Defiante shall be
responsible for securing necessary approvals to Commercial Marketing Approval by
the relevant authorities. The foregoing, as applicable, shall apply to
Sub-Licensees, as appropriate. It is understood that Defiante shall not alter,
modify, change or, in any manner, revise the Specifications without the written
approval of RegeneRx, which approval shall not be unreasonably withheld or
delayed, at RegeneRx's discretion.

         6.12   Requirement for the Finished Drug Product to Conform to
Specifications. During the Term, Defiante shall strictly comply with the
specifications for the Finished Drug Product consistent with Commercial
Marketing Approval for each country in the Territory. Additionally, RegeneRx, at
its sole expense, shall be permitted, upon mutually agreeable times, to visit
Defiante's facility, or such other facility, as is under control of Defiante for
the purposes of Finished Products manufacture, to observe the manufacture of
Finished Products. If Defiante fails to comply with such specifications as
determined by the appropriate authorities responsible for Commercial Marketing
Approval, Defiante shall use all good faith and reasonable measures to promptly
comply with the specifications for the Finished Drug Product consistent with
Commercial Marketing Approval for each country in the Territory for the Field of
Use. If despite such good faith and reasonable efforts, Defiante still fails to
meet such specifications and Sales are affected, RegeneRx shall permit Defiante
ninety (90) days to remedy such failure. Further, if, at any time during the
Term of this Agreement, Defiante or any of its Sub-Licensees and/or Distributors
directly cause one


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of the following events to occur: i) sanctions imposed on Defiante,
Sub-Licensees or Distributors by appropriate authorities that cause the Finished
Product to be removed from commercial availability or the market for more than
two (2) times during a two (2) year period; or ii) any occurrence that causes
Defiante, Sub-Licensees or Distributors to fail to make commercially available
or to make Sales of the Finished Product for a period of twelve (12) consecutive
months, then RegeneRx and Defiante shall discuss the foregoing events within
ninety (90) days of the occurrence of one of the foregoing events. Defiante,
however, shall not alter, change, modify, revise, update or, in any way, vary
the specifications for the Finished Drug Product without the written
authorization of RegeneRx, not to be unreasonably denied or delayed, unless such
alteration, change, modification, revision, update or variance is required by
the appropriate authorities responsible for Commercial Marketing Approval. The
foregoing, as applicable, shall apply to Sub-Licensees, as appropriate.

         6.13   Marketing Practices.  Defiante shall, to the extent that it is
typical and customary based upon industry standards:

                  (a)  avoid deceptive, misleading, or unethical practices that
may be detrimental to RegeneRx, RegeneRx Improvements, Joint Improvements, Bulk
Active Material, Documentation or the Finished Products;

                  (b)  not make any representations, warranties or guarantees to
any third party or entity on behalf of RegeneRx or concerning RegeneRx
Improvements, Joint Improvements, Bulk Active Material, Documentation or
Finished Products, unless mutually agreed to otherwise by the parties hereto;

                  (c)  comply with all applicable EU and local country laws and
regulations with respect to the subject matter of this Agreement; and

                  (d)  acknowledge that RegeneRx shall not participate in the
marketing, promotion or selling of the Finished Products, but will provide
information and material, at its discretion, that may be relevant and pertinent
to Defiante's activities to commercialize Finished Products in the Territory for
the Field of Use.

         6.14   Reports on Adverse Reactions to Finished Products. During the
Term herein, in the event an individual user obtains from a Customer the
Finished Product and suffers an adverse reaction, Defiante shall immediately
report to RegeneRx in detail according to applicable laws and regulations the
adverse reaction indicating such items as, but not limited to, the unit or lot
of Finished Products responsible for the adverse reaction, the date
manufactured, type of adverse reaction, patient records and what aspect, if any,
of non-compliance with the Specifications occurred that may have been a cause or
contributing factor to such adverse reaction. Further, in case of a medical
emergency involving any Finished Products, or if required by any appropriate
regulatory authority to which Finished Products are subject, RegeneRx shall have
immediate access, upon request, to all Documentation, including protocols,
regulatory documentation, and promotional materials, prepared by or for
Defiante, relating to the use or Sale of Finished Products. Defiante shall
promptly inform RegeneRx of any such medical emergency or requirement of any
appropriate regulatory authority as the foregoing requires. This Section shall
apply to Sub-Licensees. Mutatis mutandis, RegeneRx shall notify Defiante
according to this Section of any adverse reaction, side effects or the like
connected with the Finished Products and/or Bulk Active Material. On an annual
basis following commercial availability on the Effective Date, Defiante shall
deliver a report to


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RegeneRx that summarizes the occurrence of any of the foregoing events related
to adverse reactions. In the event no adverse reaction occurs during a year that
is an annual period, no report shall be required to be delivered.

         6.15   Trademark for Bulk Active Material and Trademark for Finished
Products. During the Term, RegeneRx shall provide, if appropriate, Trademark for
Bulk Active Material to Defiante for the purposes of engaging in the commercial
availability and marketing, distribution and Sales of Finished Products. The
right to use the Trademark for Bulk Active Material shall be subject to the
Trademark for Bulk Active Material Grant recited in Article 2, Section 2.2, and
the obligations under Attachment F.

                  (a)  Defiante shall be entitled to select one or more
Trademark(s) for the Finished Products. RegeneRx shall cooperate in good faith
with Defiante for choosing such Trademark for the Finished Product. Defiante
shall assume all appropriate steps to obtain, register, protect and maintain in
Defiante's or its designee's name the Trademark for the Finished Products in the
Territory. Trademark for the Finished Product shall be listed in Attachment G,
which is made a part hereof, following prompt notification to RegeneRx when such
Trademark for Finished Product is created and thereafter, made the subject of
applications for registration under appropriate trademark law in each country in
the Territory, at Defiante's expense.

                 (b)  At RegeneRx's discretion and if permitted by law, RegeneRx
shall require Defiante, its Affiliates and/or Sub-Licensees to co-brand Finished
Products with Trademark for Bulk Active Material and Trademark for the Finished
Product. The parties will cooperate in utilizing and displaying the Trademark
for the Bulk Active Material in accordance with the requirements recited in the
Trademark Style Guide and Requirements. Further, the parties will cooperate in
reviewing the display and use of the Trademark for the Finished Product in
combination with the Trademark for the Bulk Active Material.

         6.16   Application to Sub-Licensees and Affiliates. All of the
foregoing obligations in this Article 6, as appropriate, shall apply to
Sub-Licensees and Affiliates.

                                   ARTICLE 7
                CONFIDENTIAL INFORMATION, INTELLECTUAL PROPERTY

         7.1    Confidentiality, Proprietary Information And Publicity.

                  (a)  Confidentiality. By nature of this Agreement, each party
may have access to information of the other party which is considered
confidential and/or proprietary ("Information"). Information shall include, but
not be limited to, the following:

                      (i)   RegeneRx Improvements, Defiante Improvements, Joint
Improvements, Patents, Know-How, Bulk Active Material, Finished Products and
Specifications;

                      (ii)  Documentation;

                      (iii) product plans, technology, data, samples, documents,
reports, marketing strategy, equipment, personnel information, customer lists,
supplier information, business


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plans, chemical formulations, this Agreement and any other technical or business
information related to the foregoing:

                      (iv)  Information disclosed pursuant to the Nondisclosure
Agreement (Attachment H), which is incorporated herein by reference, and
effective as of April 18, 2003 and the terms therein shall apply only to the
extent that such Nondisclosure Agreement is consistent with the terms and
conditions of this Article 7 and in the event of conflict, the terms of this
Agreement shall apply and supercede; and

                      (v)   all other Information provided by either party to
the other which is clearly marked with a confidential or similar legend by the
disclosing party.

Notwithstanding the foregoing, Information shall not include information which:
(a) is or becomes a part of the public domain through no act or omission of the
receiving party; (b) was in the receiving party's lawful possession prior to the
disclosure and had not been subject to limitations on disclosure; (c) is
lawfully disclosed hereafter to the receiving party by a third party who did not
acquire the information directly or indirectly from the disclosing party; (d) is
released in writing by the disclosing party; (e) is subject to disclosure by
operation of law; or (f) is independently developed by the receiving party
without the access, use or benefit of the Information.

The receiving party shall not disclose, disseminate or distribute Information to
any third parties. The receiving party may disclose Information only to its
Affiliates, employees, subcontractors, consultants, Sub-Licensees and
Distributors, who have a need to know such Information for carrying out the
purposes of this Agreement. Further, the parties agree, both during the Term of
this Agreement and/or after the termination or expiration of this Agreement,
that all Information owned solely by one party and disclosed to the other party
shall remain sole property of the disclosing party, and the confidentiality of
the Information shall be maintained and protected by the other party with the
same effort, but not less than a reasonable degree of effort, used to protect
its own confidential and proprietary information of a like nature unless there
is an occurrence of one or more of the above conditions. Defiante shall, prior
to the disclosure of Information, obligate in writing any and all of its
Affiliates, employees, consultants, subcontractors, Sub-Licensees and
Distributors to the same degree of care and to similar obligations, as recited
herein, regarding the confidentiality and proprietary nature of Information.

The Information shall only be used as specified under and only for the purposes
of this Agreement, and for no other purpose.

No other information exchanged between the parties shall be deemed confidential
unless agreed to in writing. The confidentiality obligations under this
Agreement shall expire ten (10) years following the termination and/or
expiration of this Agreement. Notwithstanding the foregoing, in the event
certain Information is labeled as the distributing party's "Trade Secret" such
Trade Secret Information shall remain confidential beyond the ten (10) year term
unless one of the above events in (a) through (f) occur.

                  (b)  Notices. Defiante shall ensure that the Finished Products
include appropriate and proprietary markings. These markings shall include, but
are not limited to, acknowledgments and valid proprietary notices. One such
notice, for example, is the recitation of the U.S. Patent Nos. assigned/licensed
to RegeneRx, which will be timely supplied hereunder by


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RegeneRx, and which is applicable to the Finished Products, as recited in
Attachment A, and/or an appropriate Trademark for the Bulk Active Material
designation, as recited in the Trademark Style Guide and Requirements.

                  (c)  Publicity Regarding Agreement/Party References. The terms
of this Agreement shall be treated by each party as Information. No press
release or other publicity of any nature whatsoever regarding this Agreement
(including advertising or promotional activity unless expressly permitted in
this Agreement) shall be made without the other party's prior written approval.
Such approval may be withheld by the approving party in its sole and absolute
discretion; provided, however, that approval of such disclosure shall be deemed
to be given to the extent such disclosure is required to comply with the
Commercial Marketing Approval or the U.S. or local Government. When possible,
the publishing party shall give the other party five (5) business days to review
the text of such disclosure prior to publication or release. Once a publication
or release is approved, use of the same publication or press release containing
the same content shall not require additional approvals, provided that no
substantive changes are made to the content or context of the publication.

                  (d)  Publications. If Defiante desires to publish the
discoveries and findings of Defiante arising out of its research and development
activities related to Joint Improvements, RegeneRx Improvements, Defiante
Improvements, Bulk Active Material or Finished Products wherein publications
include reputable scientific journals, publications, conferences, symposiums, or
meetings papers, abstracts, manuscripts, presentations or other writings
(collectively, publications), then Defiante shall provide to RegeneRx a copy of
such publication at least sixty (60) days prior to the date on which Defiante
intends to submit such publication. RegeneRx may, in writing, on or before the
expiration of such sixty (60) day period provide comments on the proposed
publication. RegeneRx shall have the right to delay or stop the publication or
presentation in order to obtain patent protection for the discoveries and
findings contained therein, or to stop or postpone the publication to preserve
the confidentiality of any Information of a technical or business nature, or
Information related to commercialization efforts and activities. If RegeneRx
timely informs Defiante, in writing, that publication or presentation of such
publication must be stopped or delayed for the reasons above, Defiante agrees
not to publish or present such publication.

         7.2    Title to Intellectual Property.

                  (a)  Intellectual Property is defined as, but not limited to,
any ideas, information, concepts, improvements, know-how, techniques, methods,
processes, research, results, developments, work products, designs, expressions,
technology, chemical formulations, apparatus, product or function having either
patent, copyright, trade secret, trademark or any other proprietary right
associated therewith.

                  (b)  All Intellectual Property rights, title and interests in
and to RegeneRx Improvements, Patents, Know-How, RegeneRx Documentation, Bulk
Active Material, Trademark for the Bulk Active Material and products embodying
the foregoing: i) which are in existence as of the Effective Date, are held by
and shall remain vested in RegeneRx to the extent provided by RegeneRx; and/or
ii) which are generated, created or developed by RegeneRx based on or derived
from the RegeneRx Improvements, Patents, Know-How, RegeneRx Documentation, Bulk
Active Material, Trademark for the Bulk Active Material and products embodying
the foregoing during the


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Term, shall be owned by and be vested in RegeneRx to the extent provided by
RegeneRx, subject to the Grants recited in Article 2 ("RegeneRx Intellectual
Property").

                  (c)  All Intellectual Property rights, title and interests in
any Defiante Documentation, Defiante Improvements, Finished Products, and the
Trademark for the Finished Product, generated, created or developed by Defiante
based on or derived from the Finished Product or Trademark for the Finished
Product during the Term, shall be owned by and vested in by Defiante subject to
the applicable Grants recited in Article 2 ("Defiante Intellectual Property").

                  (d)  Subject to the relevant conditions herein, all
Intellectual Property rights, title and interests in and to Joint Improvements
generated, created or developed jointly by Defiante and RegeneRx during the
Term, shall be jointly owned, as equal and undivided interests, by both parties,
and jointly vested in RegeneRx and Defiante, with the right of each party upon
termination, either only as a result of natural termination under Section 9.1 or
as a result of termination for breach under Section 9.3, to exploit such Joint
Improvements without an accounting to the other party. In the event of the
procurement of Intellectual Property protection for the Joint Improvements, the
procuring party shall execute, without additional consideration, all documents
reasonably required to confirm both parties' ownership of such Intellectual
Property and to permit the procuring party to secure protection thereon.

                  (e)  In the event RegeneRx Intellectual Property results under
Section 7.2(b) above, Defiante shall execute, without additional consideration,
all documents reasonably required to confirm RegeneRx's ownership of such
Intellectual Property and to permit RegeneRx to secure protection thereon.
Additionally, in the event of termination and/or expiration, and as provided
hereunder, Defiante shall either transfer to or confirm to RegeneRx the rights
and interests in Defiante Intellectual Property consistent with the rights
reserved or granted hereunder, and, alternatively, as provided hereunder,
RegeneRx shall confirm to Defiante the rights and interests in RegeneRx
Intellectual Property consistent with the rights reserved or granted hereunder.

         7.3    Prosecution and Maintenance of Intellectual Property. RegeneRx
shall have full control over and responsibility for filing, prosecution and
maintenance of (a) Patents and (b) Know-How and c) Trademark for Bulk Active
Material during the Term of this Agreement. However, if RegeneRx does not desire
to continue to assume responsibility for the filing, prosecution or maintenance
of such Patents and Trademark for Bulk Active Material in the Territory, then
Defiante shall be permitted to assume responsibility therefore only in the
Territory. The assumption of such responsibility therefore shall, however, in no
way diminish RegeneRx's rights, title or interests therein. Should Defiante
assume such responsibility, the costs and expenses shall be deducted against any
future royalties due and owing under the Agreement from the date such costs and
expenses therefore are incurred by Defiante. Defiante shall maintain a record of
such costs and expenses for review by RegeneRx. RegeneRx shall timely notify
Defiante of its intent not to continue filing, prosecution and maintenance of
the Patents and/or Trademark for Bulk Active Material so as to permit Defiante
to have sufficient time in which to assume such responsibility therefore in the
Territory.

         7.4    Enforcement Against Third-Party Infringement. In the event
Defiante, its Affiliates, Distributors or Sub-Licensees, or RegeneRx, itself,
become aware of unauthorized, inappropriate or misappropriate use RegeneRx
Documentation or Bulk Active Material; or become aware of infringement by a
third party of any issued Patents or registered Trademark for the Bulk Active


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Material within the Territory, that party shall promptly notify the other
parties, and Defiante and RegeneRx shall discuss the most appropriate action to
take. All parties shall use their reasonable and best efforts in cooperating
with each other to terminate such infringement or unauthorized, inappropriate or
misuse without litigation; provided that, RegeneRx shall have sole control over
the actions and activities in connection therewith and shall have sole
discretion as to the non-litigation method of termination as follows:

                  (a)  Within one hundred twenty (120) days after the date of
notification of the foregoing, if attempts to abate such infringement or
unauthorized, inappropriate or misuse are unsuccessful, then RegeneRx has the
first right, but not the obligation, to bring such action, at its own expense,
against such third party, in which event Defiante or any of the foregoing
parties recited herein this Section 7.4 shall cooperate with RegeneRx, as
reasonably requested.

                  (b)  Defiante, subject to any required U.S. Government
approvals, may, on its own initiative and cost, but only upon the approval of
RegeneRx, join in any suit brought by RegeneRx under this Section 7.4; provided
that, the control over the litigation and any offer of or acceptance of
settlement associated therewith is in the sole and exclusive control and
discretion of RegeneRx.

                  (c)  All recoveries, damages and awards in a suit brought by
RegeneRx, without the joinder of Defiante, and/or all settlement amounts by
RegeneRx shall be due solely to RegeneRx. In the event that Defiante joins in
any suit brought by RegeneRx under this Section 7.4, all recoveries, damages and
awards in such joint action shall be shared equally by RegeneRx and Defiante
after the recoupment of RegeneRx's fees, expenses and costs associated with the
litigation and required payments to the U.S. Government.

                  (d)  In the event that RegeneRx elects not to institute or
prosecute any suit to enjoin or recover damages from any third-party infringer
of the issued Patents or registered Trademark for the Bulk Active Material in
the Territory or unauthorized, inappropriate or misuse of RegeneRx Improvements,
RegeneRx Documentation or Bulk Active Material in the Territory, then Defiante
alone, subject to U.S. Government approvals, but with the cooperation of
RegeneRx, at Defiante's expense, may, in its sole discretion and expense,
initiate and conduct an infringement, unauthorized, inappropriate or misuse
action against such third party. In the event of any settlement as a result of
such action , such settlement shall be subject to the approval of RegeneRx.

                  (e)  In the case of award or settlement proceeds, which may be
obtained from such action, the actual costs and expenses incurred by Defiante or
RegeneRx and any required payment obligations to the U.S. Government shall be
offset against the award or the settlement amounts; and thereafter, the
remaining proceeds shall be equally divided between Defiante and RegeneRx,
following a final and certified judgment. Defiante agrees that Defiante shall
not offer or accept any settlement within the Territory on any issued Patents or
registered Trademark for Bulk Active Material or any other claim under a
proprietary interest without RegeneRx's prior written approval.

         7.5    Challenge to Patents and Trademarks. To the extent a third-party
challenge is lodged against RegeneRx, Defiante, its Affiliates, Distributors or
Sub-Licensees based on any issued Patent or registered Trademark for Bulk Active
Material, the following shall occur:


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                  (a)  In the event Bulk Active Material, as incorporated into
the Finished Products, becomes the subject of a claim of infringement from a
third party based upon an issued Patent or registered Trademark for Bulk Active
Material in the Territory applicable to that Finished Products, the party first
receiving notice of such action shall promptly give notice to the other party
and Defiante and RegeneRx shall meet to consider the claim and the appropriate
course of action.

                  (b)  RegeneRx shall have the sole right to conduct and control
the defense of any such suit brought against RegeneRx., Defiante, its
Affiliates, Distributors or Sub-Licensee. RegeneRx shall also have the sole
right and authority to settle any such suit. Defiante, its Affiliates and/or
Sub-Licensee shall cooperate with RegeneRx in connection with the defense of
such claim, at RegeneRx costs and expenses.

                  (c)  Any royalty payments derived from Sales that are due and
payable by Defiante hereunder to RegeneRx during such action, shall continue to
be payable regardless of such action, subject to the indemnity provision in
Article 8, Section 8.4.

                  (d)  If any counterclaims occur, which result in amounts
awarded to RegeneRx then such amounts shall initially be used to offset
RegeneRx's fees and expenses incurred as a result of the action, and to meet the
obligation of any required payments to the U.S. Government, and the remaining
amount, if any, shall be payable entirely to RegeneRx following a final and
certified judgment.

                  (e)  Neither Defiante, its Affiliates, Distributors nor
Sub-Licensee shall be permitted to make an offer of or accept any settlement
related to the foregoing challenge to issued Patents without the express written
authorization of RegeneRx to do so.

                                   ARTICLE 8
                                   ---------
          REPRESENTATIONS, WARRANTIES, INDEMNIFICATION, LIMITATION OF
                          LIABILITY FOR DAMAGE CLAIMS

         8.1    RegeneRx.  RegeneRx represents and warrants that:

                  (a)  RegeneRx is a corporation validly formed and existing
under the laws of the State of Delaware, USA;

                  (b)  To the best of RegeneRx's knowledge as of the Effective
Date, there are no prior or contemporaneous assignments, grants, licenses,
encumbrances, obligations or agreements, either written, oral, express or
implied, to which it is a party, that are inconsistent with this Agreement;

                  (c)  To the best of RegeneRx's knowledge as of the Effective
Date, RegeneRx has the right to grant under Article 2 to Defiante the rights
recited in and pursuant to the terms of this Agreement under any issued Patent
or registered Trademark for Bulk Active Material, Documentation, Know-How and
RegeneRx Improvements in the Territory for the Field of Use. The parties
acknowledge that such representation shall be at all times subject to and
qualified by any applicable law, rule, regulation, ordinance, determination or
requirement in connection with the rights reserved to the Government of the
United States of America;


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                  (d)  The execution, delivery and performance of this Agreement
have been duly and effectively authorized by all necessary corporate or other
actions, that those actions do not violate, conflict with, or result in the
breach of any provision of its Articles of Incorporation, bylaws or any
comparable documents, or of any agreement to which it is a party;

                  (e)  This Agreement is binding on and enforceable against
RegeneRx in accordance with its terms; and

                  (f)  To the best of its knowledge as of the Effective Date,
that the manufacturing of Bulk Active Material and the commercialization of the
Bulk Active Material, whether or not incorporated into the Finished Products
according to this Agreement, do not infringe any third parties' rights under any
issued patents in the Territory.

         8.2    Warranty Disclaimer.  Nothing in this Agreement may be construed
as:

                  (a)  A warranty or representation by RegeneRx as to the
validity, enforceability or scope of any issued Patents or registered Trademark
for Bulk Active Material, RegeneRx Improvements or RegeneRx Documentation in the
Territory;

                  (b)  Except as provided under Section 8.1(e), a warranty or
representation that anything made, used, sold or otherwise disposed of under any
license or right granted in this Agreement is or will be free from infringement
of any patents, copyrights, trademarks and other proprietary rights of third
parties;

                  (c)  An obligation to enforce or defend any actions or suits
against or from third parties for infringement relative to Bulk Active Material,
RegeneRx Improvements or RegeneRx Documentation, except to the extent and in the
circumstances described in Sections 7.4 and 7.5; and

                  (d)  A grant by implication, estoppel, or otherwise of any
licenses under any other patent, trademark, copyright or other proprietary
interest of RegeneRx, which is not a subject of this Agreement.

FURTHER, EXCEPT AS EXPRESSLY SET FORTH IN THIS AGREEMENT, REGENERX DISCLAIMS ALL
OTHER WARRANTIES, EXPRESS OR IMPLIED, AND REGENERX MAKES NO REPRESENTATION AND
EXTENDS NO WARRANTY OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING WARRANTIES
AS TO MERCHANTABILITY, USEFULNESS, OR FITNESS FOR A PARTICULAR PURPOSE TO ANY
THIRD PARTY OR DEFIANTE RELATIVE TO REGENERX INTELLECTUAL PROPERTY, THE BULK
ACTIVE MATERIAL, TRADEMARK FOR THE BULK ACTIVE MATERIAL, REGENERX IMPROVEMENTS,
REGENERX DOCUMENTATION, PATENTS, KNOW-HOW OR INFORMATION, FINISHED PRODUCT,
JOINT IMPROVEMENTS OR THIS AGREEMENT.

         8.3    Defiante.  Defiante represents and warrants that:

                  (a)  It is a corporation validly formed and existing under the
laws of Portugal;


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                  (b)  To the best of Defiante's knowledge as of the Effective
Date, there are no prior or contemporaneous assignments, grants, licenses,
encumbrances, obligations or agreements, either written, oral, express or
implied, to which it is a party, that are inconsistent with this Agreement;

                  (c)  The execution, delivery and performance of this Agreement
have been duly and effectively authorized by all necessary corporate or other
actions, that those actions do not violate, conflict with, or result in the
breach of any provision of its Articles of Incorporation, bylaws or any
comparable documents, or of any agreement to which it is a party;

                  (d)  To the best of Defiante's knowledge, before exploiting
Finished Product, Defiante Improvements, or Defiante Documentation generated by
Defiante according to this Agreement, Defiante shall ensure that such
exploitation does not infringe any third parties' rights under any issued
patents or registered trademarks in the Territory; and

                  (e)  This Agreement is binding on and enforceable against
Defiante, its Affiliates and Sub-Licensees, as provided hereunder, and Sigma-Tau
Finanziaria SpA, under the Warranty and Undertaking, in accordance with the
terms of this Agreement

FURTHER, EXCEPT AS EXPRESSLY SET FORTH IN THIS AGREEMENT, DEFIANTE DISCLAIMS ALL
OTHER WARRANTIES, EXPRESS OR IMPLIED, AND DEFIANTE MAKES NO REPRESENTATION AND
EXTENDS NO WARRANTY OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING WARRANTIES
AS TO MERCHANTABILITY, USEFULNESS, OR FITNESS FOR A PARTICULAR PURPOSE TO ANY
THIRD PARTY OR REGENERX RELATIVE TO THE BULK ACTIVE MATERIAL, THE FINISHED
PRODUCTS, DEFIANTE IMPROVEMENTS, JOINT IMPROVEMENTS, TRADEMARK FOR FINISHED
PRODUCTS, OR THIS AGREEMENT

         8.4    Infringement Indemnity. As provided for herein under Section
7.5, RegeneRx will defend, indemnify and hold harmless Defiante against any
infringement claim by a third party relating to an issued Patent in the
Territory for the Bulk Active Material as embodied in the Finished Products that
is the subject of Sales in the Territory; provided that:

                  (a)  Defiante notifies RegeneRx in writing within thirty (30)
days of a date that a claim of infringement is received by Defiante;

                  (b)  RegeneRx has sole control of the defense and all related
settlement negotiations as provided under Article 7, Section 7.5; and

                  (c)  at RegeneRx's request, Defiante provides RegeneRx with
all necessary assistance, information and authority to perform the above.

RegeneRx shall have no liability for any claim of infringement based on: (a) use
of altered, modified Bulk Active Material not supplied by RegeneRx, or Bulk
Active Material not authorized by RegeneRx to be altered, modified or changed if
such infringement would have been avoided by the use of an unaltered, unmodified
or authorized Bulk Active Material directly supplied by RegeneRx; (b) the
combination or use of the Bulk Active Material with materials or ingredients not
furnished by RegeneRx if such infringement would have been avoided by use of the
Bulk Active Material alone;


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or (c) the rights of a third party in technology which is similar to the Bulk
Active Material previously developed by a third party cooperatively with
Defiante prior to the Effective Date of this Agreement.

In the event Bulk Active Material is held or is believed by RegeneRx to
infringe, RegeneRx shall have the option, at its expense, to:

                      (i)   modify, at RegeneRx expenses, the Bulk Active
Material to be noninfringing, subject to relevant regulatory approvals and
regulatory changes to the Commercial Marketing Approval;

                      (ii)  obtain for Defiante, at no additional expense to
Defiante, a license to continue using and distributing the Bulk Active Material,
as provided hereunder; or

                      (iii) terminate this Agreement and return to Defiante an
amount equal to the royalties paid hereunder for Sales wherein such royalties
shall be payable prorata to Defiante over a three (3) year period from the date
of termination. The foregoing shall serve as RegeneRx's entire liability and
responsibility for claims of infringement arising out of the Bulk Active
Material. RegeneRx shall not be liable for any other sums or amounts arising
therefrom, and that amount shall be the total amount payable to Defiante for
claims of infringement against Defiante, as recited herein. RegeneRx shall not
indemnify Defiante for any other claims of infringement except as expressly
stated hereunder.

ADDITIONALLY, REGENERX SHALL NOT BE LIABLE TO DEFIANTE, ITS AFFILIATES,
SUB-LICENSEES, DISTRIBUTORS OR SIGMA-TAU FINANZIARIA SPA FOR ANY SPECIAL,
CONSEQUENTIAL, INDIRECT OR INCIDENTAL DAMAGES OR LOSSES WHICH MAY HAVE RESULTED
FROM THE FOREGOING INFRINGEMENT INDEMNITY, EVEN IF REGENERX WAS INFORMED OF SUCH
POTENTIAL FOR SUCH LOSSES OR DAMAGES.

         8.5    Indemnification and Insurance.

                  (a)  Indemnification by RegeneRx. RegeneRx shall be liable for
any loss or damage to third parties due to personal injury, illness or death
directly relating or attributable to the Bulk Active Material supplied by
RegeneRx to the extent that such injury, illness or death directly results from
a cause or causes occurring prior to the delivery of any Bulk Active Material to
Defiante hereunder and is caused by the negligence or willful malfeasance of
RegeneRx or its designees in the manufacturing, storage, transportation, use,
handling or labeling of Bulk Active Material. RegeneRx shall defend, indemnify
and hold Defiante, its Affiliates, Distributors and Sub-licensees and their
agents, employees, officers and directors harmless from all suits, claims,
liabilities, losses, expenses and damages (including court costs and reasonable
attorneys' fees and expenses) of any kind or character arising from such claims
of liability, loss or damage up to the amounts of coverage available under
applicable insurance policies held by RegeneRx applicable to such claims but in
no event less than the ***.

                  (b)  Indemnification by Defiante. Defiante shall be liable for
any loss or damage to third parties due to personal injury, illness or death
directly relating or attributable to the Finished Product (and directly relating
or attributable to the Bulk Active Material to the extent the Bulk


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Active Material is manufactured by Defiante) to the extent that it results from
a cause or causes occurring subsequent to the delivery of any Bulk Active
Material to Defiante hereunder and is caused by the negligence or willful
malfeasance of Defiante or its designees in the manufacturing, storage,
transportation, use, Sale, handling, business practices or activities, including
but not limited to actions of contract or tort, or marketing of the Finished
Product or the manufacture of Bulk Active Material by Defiante including but not
limited to claims under product liabilities, including strict liabilities,
associated with Finished Product use, performance, effect or non-effect.
Defiante, its Distributors and Sub-Licensees shall defend, indemnify and hold
RegeneRx, its Affiliates and their agents, employees, officers and directors
harmless from all suits, claims, liabilities, losses, expenses and damages
(including court costs and reasonable attorneys' fees and expenses) of any kind
or character arising from such liability, loss or damage.

                  (c)  Contributory Actions. In the event claims made by third
parties occur with respect to the events recited in (a) and (b) above and the
tribunal determining such claims issues a judgment that allocates
responsibilities and liabilities between the parties, no indemnification of a
party shall occur where there is contributory causation and each party shall be
liable for the amounts of liability determined by the tribunal once the final
judgment is rendered, and therefore, each party shall bear all expense, costs
and liabilities in defending such claim from a third party.

                  (d)  Product Liability Insurance. Not later than the date of
first use of a Finished Product in humans in any country in the Territory, each
party hereto shall obtain and maintain during the term of this Agreement proper
product liability insurance issued by a reputable insurance company reasonably
acceptable to the other party, insuring each such party's respective liability
and indemnification obligations set forth above, respectively, wherein the
minimum required amount of coverage shall be an amount equal to ***. Upon
request, each party shall provide to the other party a certificate of insurance
issued by the relevant insurance company verifying the issuance of an insurance
policy complying with the provisions above.

         8.6    Agreement to Cooperate. Except where otherwise stated, in all
actions, claims and proceedings of the kind described in this Article 8, as
applicable, each of the parties shall, at its own cost, render to the other
party all assistance, furnish all documents and information, and cooperate to
the fullest extent of its capacity, including but not limited to the assistance
of, and the right to consult with, such party's technical and scientific
personnel and attorneys.

         8.7    Indemnification for Breach of Representations and Warranties.
RegeneRx shall defend, indemnify and hold harmless Defiante and its agents,
employees, officers, directors from and against any and all losses or damages
caused by a breach of any of the warranties and representations set forth in
Section 8.1 hereof, subject to Section 8.2, within the limits of liability
herein. Defiante shall defend, indemnify and hold harmless RegeneRx and its
agents, employees, officers, directors from and against any and all losses or
damages caused by a breach of any of the warranties and representations set
forth in Section 8.3 hereof, within the limits of liability herein.

         8.8    Limitation of Liability. EXCEPT WHERE OTHERWISE STATED AND
EXCEPT WITH RESPECT TO CLAIMS ARISING OUT OF MISUSE, UNAUTHORIZED OR
MISAPPROPRIATE USE OF INFORMATION OR INTELLECTUAL PROPERTY BY A PARTY HERETO, IN
NO EVENT SHALL EITHER PARTY BE LIABLE TO THE OTHER PARTY FOR ANY INDIRECT,
INCIDENTAL, SPECIAL OR CONSEQUENTIAL LOSSES OR DAMAGES, INCLUDING LOSS OF
PROFITS OR REVENUE, INCURRED BY THE


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OTHER PARTY OR ANY THIRD PARTY, WHETHER IN AN ACTION IN CONTRACT OR TORT,
INCLUDING BUT NOT LIMITED TO THE USE, RESULTS, ACTUAL OR EXPECTED, BENEFITS, OR
EFFECTS, WHETHER DIRECT, SIDE OR LATENT, OCCURRING NOW OR IN THE FUTURE FOR
APPLICATIONS OUTSIDE THE FIELD OF USE; EVEN IF THE OTHER PARTY HAS BEEN ADVISED
OF THE POSSIBILITY OF SUCH DAMAGES, RELATED TO THIS AGREEMENT, OR RELATED TO THE
POSSESSION, USE, SALE OR DISTRIBUTION OF REGENERX IMPROVEMENTS, DEFIANTE
IMPROVEMENTS, JOINT IMPROVEMENTS, KNOW-HOW, PATENTS, TRADEMARK FOR FINISHED
PRODUCTS, TRADEMARK FOR BULK ACTIVE MATERIAL, BULK ACTIVE MATERIAL, FINISHED
PRODUCTS, OR DOCUMENTATION, OR COMPLIANCE OF THE FINISHED PRODUCT AND/OR BULK
ACTIVE MATERIAL WITH THE SPECIFICATION, COMMERCIAL MARKETING APPROVAL OR
MANUFACTURING APPROVAL; OR QUALITY OR PERFORMANCE, EXPECTED OR ACTUAL, OF THE
FINISHED PRODUCT AND/OR BULK ACTIVE MATERIAL. Each party, however, acknowledges
that any breach of its obligations with respect to Information or Intellectual
Property of each party will cause such nonbreaching party irreparable injury for
which there are inadequate remedies at law and that such nonbreaching party
shall further be entitled to equitable relief in addition to all other remedies
available to it. Subject to the foregoing, each party's entire liability
hereunder shall be limited to actual and provable damages up to the amounts paid
or received hereunder, except as provided otherwise herein. Neither party shall
be liable for any further or additional amounts of money.

                                   ARTICLE 9
                                   ---------
                              TERM AND TERMINATION

         9.1    Term. This Agreement shall become effective as of the Effective
Date, and unless earlier terminated under this Article 9 this Agreement shall
expire on a country by country basis on the date that is the later of: (i) the
expiration of the last to expire of any granted Patent in the Territory having
at least one Valid Claim covering the Finished Products then on the market, its
use or manufacture, to the extent such Valid Claim could be enforced against
Defiante's activities if not for the license granted hereunder; or (ii) twelve
(12) years from the Effective Date; or (iii) the expiration of any other
exclusive or proprietary marketing rights conferred on either party (such as,
but not limited to, Orphan designation or like designations) in any country in
the Territory ("Term").

         9.2    Termination for Convenience. In the event Defiante desires to
terminate the Agreement for convenience at any time during the Term, Defiante
shall provide RegeneRx six (6) months notice to permit RegeneRx to locate
another licensee in the Territory or develop new business plans. *** that
termination, as provided hereunder in this Article 9.2, shall not entitle
Defiante, its Affiliates, Sub-Licensees or Distributors to exercise any of the
grants recited in Article 2, and Defiante, its Affiliates, Sub-Licensees or
Distributors shall not be entitled to practice any Joint Improvements. Further,
Defiante, its Affiliates, Sub-Licensees or Distributors shall not be permitted
to practice any Defiante Improvements that infringe any of the Patents, having
Valid Claims, of RegeneRx.

         9.3    Termination for Default/Remedies. This Agreement may be
terminated by a non-defaulting party, if the other party substantially fails to
perform or otherwise materially breaches any of the material terms, covenants or
provisions of this Agreement. The non-defaulting party shall


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give written notice of intent to terminate to the breaching party stating the
grounds therefore. The party receiving the notice shall have sixty (60) days
thereafter to correct such breach, except where otherwise stated in this
Agreement. If such breach is not corrected to the non-breaching party's
satisfaction within the sixty (60) day period, then this Agreement shall
automatically terminate.

                  (a)  Except as recited in Section 4.11, this Agreement shall
not be subject to termination with respect to the events that occur under
Article 4.

                  (b)  A party that brings an action based on termination shall
be entitled to seek the remedies provided under this Agreement subject to the
limitation of liabilities recited herein, and the prevailing party shall be
entitled to reasonable attorneys' fees and court and administrative costs as
determined by the Arbitration Procedures recited in Article 10, Section 10.1(d).
The remedies recited herein shall be the sole and entire remedies available to
any party hereunder under any proceeding.

         9.4    Effect of Termination.

         9.4.1  Upon termination of this Agreement by Defiante under Section 9.2
and by RegeneRx under Section 9.3, the breach by Defiante and RegeneRx's right
to termination under Section 9.3 to be confirmed by the arbitration under
Article 10 hereof:

                  (a)  Neither party shall thereby be discharged from any
liability or obligation to the other party which became due or payable prior to
the effective date of such termination; and

                  (b)  Those Sections of this Agreement which by their nature
extend beyond termination and which are explicitly set forth in Section 11.9,
shall continue; and

                  (c)  Defiante shall discontinue the use, marketing and sale of
Finished Product and shall discontinue any use of Documentation, Patents,
Know-How, Trademark for Finished Products and Trademark for Bulk Active Material
and shall cease the exercise of the grants recited in Article 2; and

                  (d)  All rights transferred to Defiante hereunder shall revert
to RegeneRx, and Defiante agrees to execute all instruments necessary and
desirable to revest said rights in RegeneRx. Defiante shall transfer all
governmental filings or approvals regarding the Finished Product in the
Territory, including Commercial Marketing Approval, clinical trial approvals, or
other authorizations for the Finished Products to RegeneRx or its designee.
Additionally, all rights granted to RegeneRx by Defiante shall survive the
termination hereunder; and

                  (e)  RegeneRx shall be entitled to receive any and all
outstanding royalty payments that are due and owing under Articles 3, 4, 5 and 6
within ten (10) days of the date of termination. RegeneRx shall be entitled to
retain all fees and royalty payments paid hereunder; and

                  (f) All manufacturing of the Finished Products shall
immediately cease except that those Finished Products in progress or those
Finished Products, which are the subject of an existing, as of the date of
termination, unfulfilled Sales orders may be completed; and thereafter, the
Finished Products shall be, at RegeneRx's discretion, promptly either turned
over to RegeneRx at


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landed cost or, in the alternative, finally sold by Defiante. In the event of a
final Sale, royalties shall be due and owing within thirty (30) days of the date
of such final Sale; and

                  (g)  All Information shall be returned to the disclosing party
within ten (10) days of the date of termination; and

                  (h)  Defiante shall promptly assign and transfer, without
further consideration, all rights, title and interests in and to Trademark for
the Finished Product to RegeneRx. Defiante shall promptly execute all documents
reasonably required to effectuate such assignment and transfer; and

                  (i)  Defiante shall promptly deliver all Defiante
Documentation to RegeneRx and assign, without further consideration, all rights,
title and interests therein to RegeneRx. Defiante shall not retain any Defiante
Documentation upon any early termination hereunder ("Defiante Documentation
Grant"); and

                  (j)  Defiante's grant to Defiante Improvements under Section
2.9 shall become irrevocable and world-wide, provided that, upon the expiration
of this Agreement as provided under this Section, RegeneRx shall be provided the
rights to use, for any purpose, manufacture and commercially exploit throughout
the world, the Defiante Improvements, free of charge and the grant shall be
deemed fully paid-up; and

                  (k)  Defiante shall have the rights to Joint Improvements as
specified under Section 7.2(d), unless otherwise agreed to by the parties.

         9.4.2  Upon termination of this Agreement by Defiante under Section
9.3, the breach by RegeneRx and Defiante's right to termination to be confirmed
by the arbitration under Article 10 hereof.

                  (a)  Neither party shall thereby be discharged from any
liability or obligation to the other party which became due or payable prior to
the effective date of such expiration or termination; and

                  (b)  Those Sections of this Agreement which by their nature
extend beyond termination and which are explicitly set forth in Section 11.9,
shall continue; and

                  (c)  ***

         9.4.3  Upon natural expiration of the Term of this Agreement under
Section 9.1 above, Defiante shall have ***. Defiante may elect to continue to
purchase the Bulk Active Material from RegeneRx or its designee under terms to
be mutually negotiated. This Section shall survive the natural expiration of
this Agreement.

         9.5    Insolvency. It is acknowledged that with respect to any
bankruptcy or insolvency proceedings by RegeneRx that does not wind up the
business but permits RegeneRx to maintain business operations, it is
acknowledged by Defiante that this Agreement shall remain in effect, provided
that a trustee is appointed to represent the interests in the assets of
RegeneRx, and that any and all royalty payments or fees shall be payable to that
trustee when such payments and fees become due and payable, hereunder.
Alternatively, if Defiante makes a filing for bankruptcy or


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insolvency under any proceeding, RegeneRx may at its discretion, promptly
terminate this Agreement without further liability except for those obligations
which survive under Article 11, Section 11.9.

                                   ARTICLE 10
                                   ----------
                              BINDING ARBITRATION

         10.1   Arbitration Procedure.

                  (a) In the event that a claim or controversy arises hereunder,
the claim or controversy shall be reduced to writing by the aggrieved party and
delivered to the nonaggrieved party. The nonaggrieved party shall be given
thirty (30) days from the date of receipt of such writing to explain and/or
remedy such claim or controversy to the aggrieved party's satisfaction. If the
aggrieved party is not satisfied with such explanation and/or remedy, the claim
or controversy shall be submitted to a Board of Arbitration for review.

                  (b) The Board of Arbitration which, except as hereinafter
provided, shall consist of three arbitrators, each party shall appoint one
arbitrator each, and the third arbitrator, who shall be the principal
arbitrator, shall be elected by the two arbitrators appointed by the parties.
The arbitration will be carried out according to the then-existing Rules of the
American Arbitration Association. The place of arbitration shall be in Delaware.
The Board of Arbitration shall determine matters in dispute in accordance with
the laws, as appropriate, of the United States, and the State of Delaware.

                  (c) Should either party fail to appoint its respective
arbitrator within thirty (30) days from the date requested by the other party,
then the arbitrator chosen by the other party shall sit alone as the sole
arbitrator. Should the two (2) arbitrators so appointed fail to appoint a third
arbitrator within thirty (30) days from the date requested by the other party,
the two (2) arbitrators shall jointly seek the intervention of the American
Arbitration Association, to appoint the third arbitrator.

                  (d) The arbitration costs and expenses shall be borne by the
parties as determined by the Board of Arbitration, except where otherwise stated
herein.

                  (e) The parties agree that the award of the arbitrators shall
be the sole and exclusive remedy between them regarding any claims,
counterclaims, issues or accountings presented or pled to the arbitrators; that
it shall be made and shall promptly be payable free of any tax, deduction or
off-set; and that any cost, fees or taxes incident to enforcing the award shall,
to the maximum extent permitted by law, be charged against the party resisting
such enforcement. Any limits of liability contained in this Agreement shall also
apply in any arbitration hereunder.

                  (f) The award shall include interest from the date of any
damages incurred for breach or other violation of the contract, and from the
date of the award until paid in full, at a rate to be fixed by the arbitrators.

                  (g) The decision of the Board of Arbitration shall be final,
binding and incontestable and may be used as a basis for judgment in the United
States, Portugal or elsewhere.


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                  (h) Neither party shall be entitled to maintain any action in
court of law or equity upon any matter in dispute until such matter shall have
been submitted and determined as hereinbefore provided and then only for the
enforcement decision of the Board of Arbitration.

                  (i) Pending the submission to arbitration and thereafter until
the Board of Arbitration publishes its awards, the parties shall, except in the
event of termination, continue to perform all their obligations under this
Agreement without prejudice to a final adjustment in accordance with the
arbitrators' award.

                                   ARTICLE 11
                                   ----------
                            MISCELLANEOUS PROVISIONS

         11.1   Agreement Registration. RegeneRx agrees to cooperate in the
preparation of any agreement and documentation which may be necessary to
register the rights granted herein with any foreign governmental agencies, if
such may be required by the laws of any such countries in which Defiante, its
Affiliates and/or its Sub-Licensees or Distributors operate, provided that such
registration does not diminish or destroy, in whole or in part, RegeneRx's
proprietary rights in, RegeneRx Improvements, Joint Improvements, Know-How,
Patents, Trademark for Bulk Active Material, Bulk Active Material or Finished
Products.

         11.2   Notices. Any notice required or permitted to be given under this
Agreement shall be in writing and shall be either transmitted by facsimile or
delivered by personal service with return receipt requested and addressed to the
party at the address stated above or such other address as the party shall, by
written notice to the other, designate. Any such notice shall be deemed received
on the day such notice is received.

         11.3   Assignment. This Agreement shall be binding upon and inure to
the benefit of the parties hereto, their successors and their permitted assigns.
This Agreement may be assigned, transferred, or hypothecated, in whole or in
part, by either party to any entity which obtains a majority interest or
controlling interest in a party or acquire substantially all of the a party's
assets as a result of a sale, acquisition, merger, or results from a corporate
reorganization. This Agreement may not be assigned, transferred or hypothecated,
in whole or in part by either party, except as provided hereinbefore. Further,
each party is permitted to assign and/or transfer this Agreement, in whole or in
part, to any of its Affiliates, upon written notice to the other party.

         11.4   Waiver; Delay. The express waiver by either party of any
provision, condition or requirement of this Agreement shall not constitute a
waiver of any future obligation to comply with such provision, condition or
requirement nor shall a waiver of one provision, condition or requirement
constitute a waiver of the remaining provisions, conditions or requirements. Any
delay or omission by either party to exercise any right or remedy under this
Agreement shall not be construed to be a waiver of any such right or remedy, or
any other right or remedy hereunder. All rights of either party under this
Agreement shall be cumulative and may be exercised separately or concurrently.

         11.5   Attorneys' Fees. In addition to any other relief it may be
awarded and except as otherwise stated herein, the prevailing party, as so
determined by the arbitrators in Article 10, in any proceeding to resolve a
dispute pertaining to matters covered by this Agreement shall be entitled to


                                       37

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                    TO A REQUEST FOR CONFIDENTIAL TREATMENT


receive its reasonable attorneys' fees and administrative costs, as so
determined by the arbitrators in Article 10, incurred in connection with such
proceeding.

         11.6   Entire Agreement. This Agreement, any Exhibits, Attachments and
any agreement specifically incorporated by reference constitute the entire
Agreement between the parties pertaining to the subject matter hereof, and
supercede all proposals, or prior and contemporaneous agreements or
understandings of the parties, which include the Deal Terms dated April 18,
2003, regarding such matter.

         11.7   Export Control/U.N. Sales of Goods/Anti-Bribery/Internet. This
Agreement and the respective performances of the parties hereunder shall be
subject to all applicable laws and regulation as well as export control laws and
regulations of the United States of America, and both parties agree that it will
comply with such laws and regulations regarding the export or reexport of the
Bulk Active Material and/or Finished Products to any country or person outside
the United States. The parties specifically disclaim the application of the 1980
United Nations Convention on the International Sales of Goods to the subject
matter of this Agreement. Additionally, both parties shall be subject to all
applicable Anti-Bribery Ordinances and Kick-Back Regulations, as applicable, to
each country in the Territory. Further, all Internet regulations and laws shall
apply to commercial activity that is the subject matter of this Agreement.

         11.8   Amendments and Modifications. No amendment or modification of
this Agreement shall be valid unless made in writing and signed by duly
authorized representatives of each party. Captions used in this Agreement are
included for the convenience of the parties only and shall be disregarded in
interpretations of this Agreement.

         11.9   Survival. The obligations recited in Articles 2, 3, 4, 7, 8, 9,
10 and 11, as applicable, shall survive the expiration and/or termination of
this Agreement.

         11.10  Governing Law and Severability. The validity, interpretation and
performance of this Agreement shall be governed by and construed under the laws
of the State of Delaware, and of the United States, as applicable, in the
competent courts of Delaware, notwithstanding the principles of any conflicts of
law. If any provision of this Agreement is held invalid or unenforceable for any
reason, the parties agree that such invalidity shall not affect the validity of
the remaining provisions of the Agreement. If any provision of this Agreement is
held invalid or unenforceable for any reason, the parties agree that such
invalidity shall not affect the validity of the remaining provisions of the
Agreement.

         11.11  Force Majeure. Except where otherwise expressly provided in this
Agreement, neither party shall be considered in default in the performance of
its representations, warranties or obligations hereunder if the accuracy or
performance is prevented, restricted or interfered with because of any event of
force majeure. The party so affected shall give notice promptly to the other
party in writing of the event of force majeure, and, thereupon, the affected
party shall be excused from those of its obligations hereunder which it is
unable to perform because of that event of force majeure for as long as that
event of force majeure shall remain in force plus a period of thirty (30) days.

         11.12  Counterparts.  This Agreement may be signed in multiple
counterparts.  Signatures may be transmitted by facsimile telecopier.


                                       38

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CERTAIN PORTIONS OF THIS DOCUMENT INDICATED BY *** HAVE BEEN REDACTED PURSUANT
                    TO A REQUEST FOR CONFIDENTIAL TREATMENT


         11.13  Independence of Parties. RegeneRx and Defiante are independent
contractors and neither party is the legal representative, agent, joint
venturer, partner, or employee of the other party for any purpose whatsoever.
Neither party has any right or authority to assume or create any obligation of
any kind or to make any representation or warranty on behalf of the other party,
whether express or implied, or to bind the other party in any respect
whatsoever, except as expressly agreed to herein.

         11.14  Reasonable Interpretation of Clauses. The parties acknowledge
that the restrictions and/or rights contained in this Agreement are the result
of extended discussion between the parties relating to the development,
marketing and distribution of products incorporating Thymosin Beta 4. The
parties further acknowledge that the restrictions are reasonable in scope, time,
territory or legal validity, and that if any court or Board of Arbitration
having jurisdiction over the parties should determine that any part of this
Agreement is illegal, invalid or unenforceable for any reason, it is the intent
of the parties that any such illegal, invalid or unenforceable provision shall
be replaced by a valid provision which will implement the commercial purpose of
this Agreement.

IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be duly
executed effective as of the date first written above.




REGENERX BIOPHARMACEUTICALS, INC.          DEFIANTE FARMACEUTICA LDA



By:

---------------------------------          BY:---------------------------------
J.J. Finkelstein                           Name:
President and CEO                          Title:


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                                  ATTACHMENT A

                                    PATENTS

--------------- ------------------------------ --------------- -----------------
                Title                          Priority Date   Status
--------------- ------------------------------ --------------- -----------------
***             ***                            ***             ***
--------------- ------------------------------ --------------- -----------------
***             ***                            ***             ***
--------------- ------------------------------ --------------- -----------------
***             ***                            ***             ***
--------------- ------------------------------ --------------- -----------------
***             ***                            ***             ***
--------------- ------------------------------ --------------- -----------------
***             ***                            ***             ***
--------------- ------------------------------ --------------- -----------------
***             ***                            ***             ***
--------------- ------------------------------ --------------- -----------------
***             ***                            ***             ***
--------------- ------------------------------ --------------- -----------------
***             ***                            ***             ***
--------------- ------------------------------ --------------- -----------------
***             ***                            ***             ***
--------------- ------------------------------ --------------- -----------------
***             ***                            ***             ***
--------------- ------------------------------ --------------- -----------------
***             ***                            ***             ***
--------------- ------------------------------ --------------- -----------------
***             ***                            ***             ***
--------------- ------------------------------ --------------- -----------------
***             ***                            ***             ***
--------------- ------------------------------ --------------- -----------------
***             ***                            ***             ***
--------------- ------------------------------ --------------- -----------------
***             ***                            ***             ***
--------------- ------------------------------ --------------- -----------------
***             ***                            ***             ***
--------------- ------------------------------ --------------- -----------------
***             ***                            ***             ***
--------------- ------------------------------ --------------- -----------------
***             ***                            ***             ***
--------------- ------------------------------ --------------- -----------------


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CERTAIN PORTIONS OF THIS DOCUMENT INDICATED BY *** HAVE BEEN REDACTED PURSUANT
                    TO A REQUEST FOR CONFIDENTIAL TREATMENT


                                  ATTACHMENT B

                  THYMOSIN (Beta) 4 TENTATIVE RELEASE SPECIFICATIONS


                                      ***


                                       41


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CERTAIN PORTIONS OF THIS DOCUMENT INDICATED BY *** HAVE BEEN REDACTED PURSUANT
                    TO A REQUEST FOR CONFIDENTIAL TREATMENT


                                  ATTACHMENT C

                                   TERRITORY



Tier 1 Countries
----------------
***


Tier 2 Countries
----------------
***


Tier 3 Countries
----------------
***


                                       42


<PAGE>


                                  ATTACHMENT D

            WARRANTY AND UNDERTAKING BETWEEN REGENERX AND SIGMA-TAU

         Sigma-Tau Finanziaria SpA, Viale Sud Africa, 20 00144 Rome Italy
("Sigma-Tau") guarantees the performance of Defiante or its Affiliates as set
forth in this Agreement. In the event Defiante or its Affiliates fail to perform
its obligations, following an opportunity to cure as provided under this
Agreement, Sigma-Tau shall assume all liability, including responsibility for
damages, that result from Defiante's or its Affiliates' breach of this Agreement
relative to performance by Defiante or its Affiliates unless Sigma-Tau, itself,
assumes, at its discretion, all performance obligations under this Agreement.
Sigma-Tau, however, shall have no liability to RegeneRx if Defiante or its
Affiliates perform under this Agreement. This Warranty and Undertaking shall
survive any termination under this Agreement.

REGENERX BIOPHARMACEUTICALS, INC.         SIGMA-TAU Finanziaria SpA



By:                                       By:
   ------------------------------            ----------------------------
J.J. Finkelstein                             Name:
President and CEO                                 -----------------------
                                             Title:----------------------


                                       43


<PAGE>


                                  ATTACHMENT E

                                NIH REQUIREMENTS

NATIONAL  INSTITUTE  OF HEALTH  ("NIH"),  THE CENTERS  FOR  DISEASE  CONTROL AND
PREVENTION  ("CDC"), OR THE FOOD AND DRUG  ADMINISTRATION  ("FDA"),  HEREINAFTER
SINGULARLY OR  COLLECTIVELY  REFERRED TO AS "PHS",  AGENCIES OF THE UNITED STATE
PUBLIC HEALTH SERVICE AND HUMAN SERVICES ("DHHS") AGENCY REQUIREMENTS

RegeneRx declares that PHS have the following rights on the subject matter of
this Agreement.

STATUTORY AND PHS REQUIREMENTS AND RESERVED GOVERNMENT RIGHTS
-------------------------------------------------------------

5.01(a)           PHS reserves on behalf of the Government an irrevocable,
                  nonexclusive, nontransferable, royalty-free license for the
                  practice of all inventions licensed under the Licensed Patent
                  Rights throughout the world by or on behalf of the Government
                  and on behalf of any foreign government or international
                  organization pursuant to any existing or future treaty or
                  agreement to which the Government is a signatory. Prior to the
                  First Commercial Sale, Licensee agrees to provide PHS
                  reasonable quantities of Licensed Products or materials made
                  through the Licensed Processes for PHS research use.

5.01(b)           In the event that Licensed Patent Rights are Subject
                  Inventions made under a Cooperative Research and Development
                  Agreement (CRADA), Licensee grants to the Government, pursuant
                  to 15 U.S.C. 3710a(b)(1)(A), a nonexclusive, nontransferable,
                  irrevocable, paid-up license to practice Licensed Patent
                  Rights or have Licensed Patent Rights practiced throughout the
                  world by or on behalf of the Government. In the exercise of
                  such license, the Government shall not publicly disclose trade
                  secrets or commercial or financial information that is
                  privileged or confidential within the meaning of 5 U.S.C.
                  552(b)(4) or which would be considered as such if it had been
                  obtained from a non-Federal party. Prior to the First
                  Commercial Sale, Licensee agrees to provide PHS reasonable
                  quantities of Licensed Products or materials made through the
                  Licensed Processes for PHS research use.

5.02              Licensee agrees that products used or sold in the United
                  States embodying Licensed Products or produced through use of
                  Licensed Processes shall be manufactured substantially in the
                  United States, unless a written waiver is obtained in advance
                  from PHS.

5.03              Licensee acknowledges that PHS may enter into future
                  Cooperative Research and Development Agreements (CRADAs) under
                  the Federal Technology Transfer Act of 1986 that relate to the
                  subject matter of this Agreement. Licensee agrees not to
                  unreasonably deny requests for a Research License from such
                  future collaborators with PHS when acquiring such rights is
                  necessary in order to make a Cooperative Research and
                  Development Agreement (CRADA) project feasible. Licensee may
                  request an opportunity to join as a party to the proposed
                  Cooperative Research and Development Agreement (CRADA).


                                       44


<PAGE>


5.04(a)           In addition to the reserved license of Paragraph 5.01 above,
                  PHS reserves the right to grant nonexclusive Research Licenses
                  directly or to require Licensee to grant nonexclusive Research
                  Licenses on reasonable terms. The purpose of this Research
                  License is to encourage basic research, whether conducted at
                  an academic or corporate facility. In order to safeguard the
                  Licensed Patent Rights, however, PHS shall consult with
                  Licensee before granting to commercial entities a Research
                  License or providing to them research samples of materials
                  made through the Licensed Processes.

5.04(b)           In exceptional circumstances, and in the event that Licensed
                  Patent Rights are Subject Inventions made under a Cooperative
                  Research and Development Agreement (CRADA), the Government,
                  pursuant to 15 U.S.C. 3710a(1)(B), retains the right to
                  require the Licensee to grant to a responsible applicant a
                  nonexclusive, partial exclusive, or exclusive sublicense to
                  use Licensed Patent Rights in Licensee's field of use on terms
                  that are reasonable under the circumstances; or if Licensee
                  fails to grant such a license, the Government retains the
                  right to grant the license itself. The exercise of such rights
                  by the Government shall only be in exceptional circumstances
                  and only if the Government determines (i) the action is
                  necessary to meet health or safety needs that are not
                  reasonably satisfied by Licensee; (ii) the action is necessary
                  to meet requirements for public use specified by Federal
                  regulations, and such requirements are not reasonably
                  satisfied by Licensee; or (iii) the Licensee has failed to
                  comply with an agreement containing provisions described in 15
                  U.S.C. 3710c(4)(B). The determination made by the Government
                  under this Article is subject to administrative appeal and
                  judicial review under 35 U.S.C. 203(2).

RECORDKEEPING
-------------

8.01              Licensee agrees to keep accurate and correct records of
                  Licensed Products made, used, sold, or imported and Licensed
                  Processes practiced under this Agreement appropriate to
                  determine the amount of royalties due PHS. Such records shall
                  be retained for at least five (5) years following a given
                  reporting period and shall be available during normal business
                  hours for inspection at the expense of PHS by an accountant or
                  other designated auditor selected by PHS for the sole purpose
                  of verifying reports and payments hereunder. The accountant or
                  auditor shall only disclose to PHS information relating to the
                  accuracy of reports and payments made under this Agreement. If
                  an inspection shows an underreporting or underreporting or
                  underpaying in excess of five percent (5%) for any twelve (12)
                  month period, then Licensee shall reimburse PHS for the cost
                  of the inspection at the time Licensee pays the unreported
                  royalties, including any late charges as required by Paragraph
                  9.08 of this Agreement. All payments required under this
                  Paragraph shall be due within thirty (30) days of the date PHS
                  provides Licensee notice of the payment due.

PERFORMANCE
-----------

10.01             Licensee shall use its reasonable best efforts to bring the
                  Licensed Products and Licensed Processes to Practical
                  Application. "Reasonable best efforts" for the purposes of
                  this provision shall include adherence to the Commercial
                  Development


                                       45


<PAGE>


                  Plan at Appendix F and performance of the Benchmarks at
                  Appendix E. The efforts of a sub-licensee shall be considered
                  the efforts of Licensee.

10.02             Upon the First Commercial Sale, until the expiration of this
                  Agreement, Licensee shall use its reasonable best efforts to
                  make Licensed Products and Licensed Processes reasonably
                  accessible to the United States public.

NEGATION OF WARRANTIES AND INDEMNIFICATION
------------------------------------------

12.05             Licensee shall indemnify and hold PHS, its employees,
                  students, fellows, agents, and consultants harmless from and
                  against all liability, demands, damages, expenses, and losses,
                  including but not limited to death, personal injury, illness,
                  or property damage in connection with or arising out of: a)
                  the use by or on behalf of Licensee, its sub-licensees,
                  directors, employees, or third parties of any Licensed Patent
                  Rights; or b) the design, manufacture, distribution, or use of
                  any Licensed Products, Licensed Processes or materials by
                  Licensee, or other products or processes developed in
                  connection with or arising out of the Licensed Patent Rights.
                  Licensee agrees to maintain a liability insurance program
                  consistent with sound business practice.

TERM, TERMINATION, AND MODIFICATION OF RIGHTS
---------------------------------------------

13.07             PHS reserves the right according to 35 U.S.C.ss.209(f)(4) to
                  terminate or modify this Agreement if it is determined that
                  such action is necessary to meet requirements for public use
                  specified by federal regulations issued after the date of the
                  license and such requirements are not reasonably satisfied by
                  Licensee.

13.08             Within thirty (30) days of receipt of written notice of PHS's
                  unilateral decision to modify or terminate this Agreement,
                  Licensee may, consistent with the provisions of 37 U.S.C.
                  404.11, appeal the decision by written submission to the
                  designated PHS official. The decision of the designated PHS
                  official shall be the final agency decision. Licensee may
                  thereafter exercise any and all administrative or judicial
                  remedies that may be available.

13.09             Within ninety (90) days of expiration or termination of this
                  Agreement under this Article 13, a final report shall be
                  submitted by Licensee. Any royalty payments, including those
                  incurred but not yet paid (such as the full minimum annual
                  royalty), and those related to patent expense, due to PHS
                  shall become immediately due and payable upon termination or
                  expiration. If terminated under this Article 13, sub-licensees
                  may elect to convert their sublicenses to direct licenses with
                  PHS pursuant to Paragraph 4.03. Unless otherwise specifically
                  provided for under this Agreement, upon termination or
                  expiration of this Agreement, Licensee shall return all
                  Licensed Products or other materials included within the
                  Licensed Patent Rights to PHS or provide PHS with
                  certification of the destruction thereof.


                                       46


<PAGE>


                                  ATTACHMENT F

                     TRADEMARK STILE GUIDE AND REQUIREMENTS

1.    "Trademarks" as used only in this Attachment F mean the TRADEMARK FOR BULK
ACTIVE MATERIAL

2.    Style Guide Adherence. Defiante will adhere to RegeneRx's style guide,
which is attached hereto, which Defiante shall not be permitted to alter, modify
or change, in any manner, the Trademarks or use the Trademarks in combination
with other marks or designs, unless specifically authorized, in writing, by
RegeneRx to do so.

3.    Ownership. Defiante hereby acknowledges and recognized that RegeneRx owns
all rights, title and interests in the Trademarks, and any use of the Trademarks
by Defiante shall not diminish any rights, title or interest in such Trademarks.
Defiante further agrees not to take any action inconsistent with such ownership
including, without limitation, any action to challenge, dilute, diminish or harm
RegeneRx's rights and interests in the Trademarks or its reputation or goodwill
symbolized by the Trademarks. Defiante acknowledges that Defiante's use of the
Trademarks pursuant to this Agreement and any goodwill established thereby shall
inure to the sole benefit of RegeneRx. Defiante shall ensure that the integrity
of the Trademarks is maintained in accordance with this Attachment.

4.    Cooperation. Defiante shall use reasonable efforts to support RegeneRx in
policing and protecting the Trademarks. Defiante shall make reasonable efforts
to promptly notify RegeneRx of any activity or action by a third party known to
Defiante and that Defiante reasonably considers may infringe or, in any way,
harm the Trademarks. Such cooperation by Defiante shall be at the sole expense
of RegeneRx.

5.    Limit on Registration. Defiante will not attempt to register any of the
Trademarks as a trademark with any official trademark office or with any other
like regulatory office anywhere in the world. Further, Defiante will not
display, use or register any marks, which are substantially similar to the
Trademarks.


                                       47


<PAGE>


                                   EXHIBIT 1

                      PROPER DISPLAY AND USE OF TRADEMARKS

                              [TBD IN THE FUTURE]


                                       48


<PAGE>


                                  ATTACHMENT G

                               DEFIANTE TRADEMARKS

                               [TBD IN THE FUTURE]


                                       49


<PAGE>


                                  ATTACHMENT H

                   NONDISCLOSURE BETWEEN DEFIANTE AND REGENERX

                                  [TO BE ADDED]


                                       50