Document:

<PAGE>
                                                                 Exhibit 10.6(d)

                              EMPLOYMENT AGREEMENT

      This Agreement, effective as of January 31, 2003, is entered into by and
between Applied Graphics Technologies, Inc., a Delaware corporation ("AGT"), and
Kenneth G. Torosian, (hereinafter referred to as the "Employee"), an individual
presently residing at 13 North Washington Street, Tarrytown, New York 10591. In
consideration of the mutual covenants set forth herein, the parties agree as
follows:

      1. Employment Term. Subject to the further terms and conditions of this
Agreement, AGT shall continue to employ Employee for the period beginning on
January 31, 2003 (the "Commencement Date") and ending on January 30, 2005 (the
"Term"). After the Term, Employee shall be an employee "At will" and may be
terminated by AGT at any time with or without cause.

      2. Compensation.

            a. AGT will pay Employee a salary at the rate of Three Hundred
Thousand Dollars ($300,000) per annum ("Base Salary"). The Base Salary will be
reviewed annually and may, in the sole discretion of the Board of Directors, be
increased but may not be reduced.

            b. Employee will be eligible to receive a performance bonus with
respect to 2003 and for future periods based upon the Management Incentive Plan
("MIP") approved by the Board with respect to each such period. In the event
Employee's employment shall terminate or expire for any reason other than for
"Cause" pursuant to paragraph 5(a) herein, after the end of any period with
respect to which an MIP bonus was based, but before said bonus was paid,
<PAGE>
Employee shall be entitled to the full amount of said bonus to which he would
otherwise have been entitled had his employment not terminated or expired, such
bonus to be payable at the time, and in the manner, that MIP bonuses are paid to
comparable employees. In addition, Employee shall be eligible to receive any
additional bonus that may be approved by the Board of Directors in its sole
discretion.

            c. The Base Salary and bonuses referred to above represent all of
Employee's cash compensation, and accordingly, Employee shall not be entitled to
any overtime, weekend or holiday compensation. All payments made pursuant to
this Agreement shall be less applicable withholdings and deductions.

            d. Employee shall be eligible to participate in those insurance,
retirement and other benefits generally provided to AGT's other senior
executives of similar rank and tenure from time to time.

            e. Employee shall be reimbursed for all reasonable travel and
entertainment expenses incurred in the furtherance of AGT's business, upon
submission by Employee of appropriate documentation in accordance with AGT's
policies as are in effect from time to time.

            f. AGT shall provide Employee with an all-inclusive automobile
allowance of $800 per month.

      3. Duties. Employee agrees to fulfill the duties of Senior Vice-President
and Chief Financial Officer and Treasurer as such duties are defined by AGT's
Board of Directors. In light of the requirements of the Company as determined by
the Board of Directors, it is understood that the Employee's duties may be
modified from time to time in the future. However, the Employee's duties must,
at a minimum, consist of those customarily performed by the Chief Financial
Officer. Employee's reporting relationship shall be as determined by the Board
of Directors in its sole discretion; provided that, unless and until the Board
determines otherwise,

                                       2
<PAGE>
Employee shall report to Joe Vecchiolla in his capacity as President and Chief
Operating Officer. Employee shall devote all of his business efforts to the
performance of his duties hereunder and shall do so to the best of his
abilities. The Employee's principal office, which is currently in New York,
shall be in a location determined by the Board of Directors. Employee will
travel both in the United States and abroad as necessary and appropriate to
fulfill his duties.

      4. Vacation. Employee shall be entitled to four (4) weeks vacation during
each year of the Term, to be taken at such times as shall be agreed between
Employee and the entity or person to whom he reports. Vacation days will accrue
and be paid in accordance with AGT's policies as are in effect from time to
time.

      5. Termination. Subject to the provisions of this Paragraph 5, either AGT
or

Employee may terminate this Agreement prior to the expiration of the Term, as
provided for hereinbelow.

      (a)   AGT shall have the right to terminate this Agreement for Cause (as
            hereinafter defined), whereupon the Term shall be at an end.
            Employee shall have the right to terminate this Agreement for Good
            Reason (as hereinafter defined), whereupon the Term shall be at an
            end. If AGT terminates this Agreement for other than Cause or
            Employee terminates this Agreement for Good Reason, then AGT shall
            pay and/or provide to Employee the following:

            (i)   all accrued but unpaid amounts payable hereunder with respect
                  to the period prior to the date of termination (including,
                  without limitation, base

                                       3
<PAGE>
                  salary, any unpaid bonus which may have been awarded to or
                  earned by Employee, unused vacation pay and reimbursable
                  expenses); and

            (ii)  The sum of (A) all Base Salary which would have become payable
                  to Employee under this Agreement as if this Agreement had not
                  been terminated and Employee remained employed by AGT for a
                  period of 12 months following such termination, (the
                  "Severance Period"), and (B) the aggregate amount by which all
                  then unvested stock options are "in the money" on the date of
                  termination, said amount to be calculated by subtracting from
                  the market value of AGT stock as of the date of termination
                  the applicable exercise prices of the stock options;

            (iii) The amounts referred to in subparagraphs (i) and (ii) above
                  are sometimes hereinafter referred to as the "Severance
                  Payments". The Severance Payments shall be paid in a lump sum
                  (without present value discount) within thirty (30) days after
                  the date of termination, except that any unpaid MIP bonus to
                  which Employee is entitled pursuant to paragraph 2(b) herein
                  shall be paid as provided in said paragraph. As a condition to
                  Employee's receipt of the Severance Payments, Employee will be
                  required to execute a Release in the form attached hereto as
                  SCHEDULE OF RELEASE; and

            (iv)  during the maximum period permitted by COBRA, but in no event
                  past the end of the Severance Period, AGT will provide
                  Employee, at AGT's expense, with COBRA coverage. During the
                  Severance Period, Employee

                                       4
<PAGE>
                  shall not be entitled to any other benefits provided in
                  paragraph 2(d) except any conversion and other rights which
                  survive termination of employment under any group life,
                  disability insurance and/or other benefit plans of AGT in
                  which Employee participates or participated as an employee of
                  AGT. Anything contained herein to the contrary, AGT's
                  obligation to provide COBRA benefits shall terminate upon the
                  date the Employee is first eligible for medical insurance
                  related to his new employment.

      (b)   If AGT terminates this Agreement for Cause, or if Employee dies or
            becomes permanently disabled (as hereinafter defined), then AGT
            shall pay to Employee all accrued but unpaid amounts hereunder with
            respect to the period prior to the date of termination, death or
            disability (including, without limitation, Base Salary, unused
            vacation pay and reimbursable expenses and, in the event Employee
            dies or becomes permanently disabled, any unpaid bonus which may
            have been awarded to or earned by Employee); said amounts to be paid
            to Employee (or his estate) within 30 days after the date of such
            termination, death or disability, except that any unpaid MIP bonus
            to which Employee is entitled pursuant to paragraph 2(b) herein
            shall be paid as provided in said paragraph.

      (c)   For purposes of this Agreement, "Cause" shall mean: (i) indictment
            for, conviction of or pleas of guilty or nolo contendre to any
            felony (other than an offense involving a motor vehicle) or business
            related misdemeanor; (ii) theft, fraud or embezzlement; (iii) an act
            of gross neglect or gross misconduct; (iv)

                                       5
<PAGE>
            habitual drug or alcohol abuse; (v) excessive absenteeism not
            related to illness; (vi) the intentional failure to perform assigned
            duties; (vii) a material breach of any of the provisions of this
            Agreement; (viii) the commission of any other action with the intent
            to harm or injure AGT, its parents, subsidiaries or affiliates;
            which, in the case of clauses (v), (vi), (vii) and/or (viii) above,
            are not remedied by Employee within thirty (30) days after receipt
            by Employee of written notice from the Chairman of the Board of
            Directors of AGT (the "Board").

      (d)   For purposes of this Agreement, "Good Reason" shall mean (i) if any
            payment to be made by AGT to Employee is not made when due and
            remains unpaid for fifteen (15) days after written notice from
            Employee, and/or (ii) any other material breach by AGT of this
            Agreement which is not remedied within thirty (30) days after
            receipt of written notice thereof to AGT by Employee (including,
            without limitation, any demotion in Employee's title or position
            and/or any material diminution of Employee's powers, duties or
            responsibilities; provided that, if Employee ceases to serve as
            Treasurer and perform the duties of that office, such change in
            status will not constitute "Good Reason" pursuant to this
            subparagraph).

      (e)   "Permanent disability" shall mean physical or mental illness,
            disability or disfigurement which renders Employee incapable of
            performing his normal services hereunder for a continuous period of
            8 weeks, or an aggregate of 16 weeks during any 52-week period. In
            the event Employee is disabled less than such 8 or 16 weeks,
            respectively, Employee shall nonetheless be entitled to full

                                       6
<PAGE>
            compensation during such period. In the event of termination as a
            result of disability under 5(b) above, Employee shall, in addition
            to any other payments or benefits hereunder, be entitled to receive
            a severance payment pursuant to company policy, but not less than
            one (1) year of Base Salary.

      (f)   In the event that, on January 30, 2005, (A) Employee is still
            employed by AGT, and (B) for any reason whatsoever, AGT has failed
            to offer to enter into a written agreement extending the term of
            Employee's employment by AGT for a period of at least one (1) year
            beyond January 30, 2005, upon terms at least as favorable to
            Employee as those set forth herein, then AGT shall pay and/or
            provide to Employee the following:

                  (i)   all accrued but unpaid amounts payable hereunder with
                        respect to the period ending on January 30, 2005
                        (including, without limitation, base salary, any unpaid
                        bonus which may have been awarded to or earned by
                        Employee, unused vacation pay and reimbursable
                        expenses); and

                  (ii)  all base salary which would have become payable to
                        Employee under this Agreement, as if this term of this
                        Agreement had not expired and Employee remained employed
                        by AGT for an additional period of one (1) year
                        following such expiration, (the "Continuation Period").

                  (iii) the amounts referred to in subparagraphs (i) and (ii)
                        above are

                                       7
<PAGE>
                        sometimes hereinafter referred to as the "Continuation
                        Payments". The Continuation Payments shall be paid in a
                        lump sum (without present value discount) within thirty
                        (30) days after the date of the expiration of the Term
                        except that any unpaid MIP bonus to which Employee is
                        entitled pursuant to paragraph 2(b) herein shall be paid
                        as provided in said paragraph. As a condition to
                        Employee's receipt of the Continuation Payments,
                        Employee will be required to execute a Release in the
                        form attached hereto as SCHEDULE OF RELEASE; and

                  (iv)  during the maximum period permitted by COBRA, but in no
                        event past the end of the Continuation Period, AGT will
                        provide Employee, at AGT's expense, with COBRA coverage.
                        During the Continuation Period, Employee shall not be
                        entitled to any other benefits provided in paragraph
                        2(d) except any conversion and other rights which
                        survive termination of employment under any group life,
                        disability insurance and/or other benefit plans of AGT
                        in which Employee participates or participated as an
                        employee of AGT. Anything contained herein to the
                        contrary, AGT's obligation to provide COBRA benefits
                        shall terminate upon the date the employee is first
                        eligible for medical insurance related to his new
                        employment.

      (g)   Employee shall not be obligated to seek or accept other employment
            in mitigation

                                       8
<PAGE>
            of any amounts payable hereunder and the obtaining of any such other
            employment shall in no event effect any reduction of AGT's
            obligations to make the payments or, except as provided in
            subsections (a)(iv) and (f)(iv) above, to provide the benefits
            required hereunder."

      6. Noncompetition, Nonsolicitation and Confidentiality. As a material
inducement to continue to employ him, Employee agrees to execute the
Noncompetition, Nonsolicitation and Confidentiality Agreement attached hereto as
Exhibit A, the terms of which are incorporated herein by reference.

      7. Absence of Restrictions. Employee represents and warrants that he is
not a party to any agreement or contract pursuant to which there is any
restriction or limitation upon him entering into this Agreement or performing
the duties called for by this Agreement.

      8. Notices. All notices, consents and other communications required or
permitted to be given hereunder shall be in writing and delivered personally or
sent by certified or registered mail, postage prepaid, as follows:

            a.    if to Employee, to: Kenneth G. Torosian, 13 North Washington
                  Street, Tarrytown, New York 10591

            b.    if to AGT, to: Chairman of the Board of Directors, 450 West
                  33rd Street, New York, New York 10001-2681, with a copy to
                  Martin D. Krall, Chief Legal Officer, at 450 West 33rd Street,
                  Third Floor, New York New York 10001-2681.

      Any notice so given shall be deemed received when delivered personally,
or, if mailed,

                                       9
<PAGE>
three days after it is deposited, postage prepaid, by certified mail, in the
United States mail. Either party may change the address to which notices are to
be sent by giving written notice of such change of address to the other party in
the manner herein provided for giving notice.

      9. General.

      a.    Any controversy or claim arising out of or relating to this
            Agreement, or any breach thereof, shall be subject to resolution in
            the state or federal courts in New York and shall be governed by and
            construed and enforced in accordance with the laws of the State of
            New York applicable to agreements made and to be performed entirely
            in New York without giving effect to principles of conflicts of laws
            thereof.

      b.    The section headings contained herein are for reference purposes
            only and shall not in any way affect the meaning or interpretation
            of this Agreement. This Agreement sets forth the entire agreement
            and understanding of the parties hereto concerning the subject
            matter hereof, and supersedes all prior agreements, arrangements and
            understandings between the parties hereto.

      c.    AGT may assign its rights and obligations under this Agreement to
            any successor thereto or to any corporation or other entity
            controlled, or under common control with AGT or any of its
            affiliates. This Agreement is personal to employee, and neither this
            Agreement nor any of Employee's rights or obligations hereunder may
            be assigned, pledged or encumbered by him, without the prior written
            approval of AGT.

                                       10
<PAGE>
      d.    This Agreement may be amended, modified, superseded or canceled, and
            the terms or covenants hereof may be waived, only by a written
            instrument executed by both parties hereto, or, in the case of a
            waiver, by the party waiving compliance. The failure of either party
            at any time or times to require performance of any provision hereof
            shall in no manner affect the right at a later time to enforce the
            same. No waiver by either party of the breach of any term or
            covenant contained in this Agreement, whether by conduct or
            otherwise, in any one or more instances, shall be deemed to be, or
            construed as a further or continuing waiver of any such breach or
            waiver of the breach of any other term or covenant in this
            Agreement.

      e.    In the event that any one or more of the provisions of this
            Agreement shall be determined to be invalid or unenforceable in any
            respect, the validity and enforceability of the remaining provisions
            of this Agreement shall not in any way be affected or impaired
            thereby.

      f.    This Agreement may be executed in counterparts; each of which shall
            be deemed to be an original but all of which together shall be
            deemed to be one and the same instrument.

                                       11
<PAGE>
      g.    Except with regard to employee's obligations under the
            Noncompetition, Nonsolicitation and Confidentiality Agreement
            attached hereto as Exhibit A, and with regard to AGT's obligations
            under Paragraphs 5, this Agreement shall be of no further force and
            effect and AGT shall have no further obligations hereunder after the
            expiration or termination of this Agreement.

IN WITNESS WHEREOF, the parties have executed this Agreement as of the date
shown below.

KENNETH G. TOROSIAN                      APPLIED GRAPHICS TECHNOLOGIES, INC.

By: _____________________________        By: _______________________________

Dated: __________________________        Title: ____________________________

                                         Dated: ____________________________

                                       12<PAGE>

                                                                   EXHIBIT 10.23

================================================================================

                   COLLABORATION, LICENSE AND OPTION AGREEMENT

                                 By and Between

                               NOVARTIS PHARMA AG,

                      NOVARTIS PHARMACEUTICALS CORPORATION

                                       AND

                         REGENERON PHARMACEUTICALS, INC.

                           Dated as of March 28, 2003

================================================================================

<PAGE>

                                TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                                                                    Page
                                                                                                                    ----
<S>                                                                                                                 <C>
ARTICLE I DEFINITIONS............................................................................................     2

ARTICLE II COOPERATION...........................................................................................    19
         2.1  Scope of Cooperation...............................................................................    19
         2.2  Compliance With Law................................................................................    19
         2.3  Diligence..........................................................................................    19
         2.4  Reservation of Rights..............................................................................    19
         2.5  Further Assurances and Transaction Approvals.......................................................    20

ARTICLE III MANAGEMENT...........................................................................................    20
         3.1  Committees/Management..............................................................................    20
         3.2  The Joint Steering Committee.......................................................................    21
         3.3  Responsibilities of the JSC........................................................................    22
         3.4  Joint Operating Committee..........................................................................    22
         3.5  JOC Responsibilities...............................................................................    23
         3.6  Alliance Management Representative.................................................................    26
         3.7  Resolution of Governance Matters...................................................................    26

ARTICLE IV EXISTING PATENT AND KNOW-HOW RIGHTS; LICENSE GRANTS...................................................    27
         4.1  Regeneron License Grants Regarding Trap-1..........................................................    27
         4.2  Novartis License Grants Regarding the IL-1 Antibody................................................    28
         4.3  Regeneron License Grants Regarding Trap-2..........................................................    28
         4.4  Technology Transfer................................................................................    28
         4.5  Sublicenses........................................................................................    29

ARTICLE V DEVELOPMENT AND OPT-IN RIGHTS..........................................................................    29
         5.1  Pre-Phase III Development of the IL-1 Antibody.....................................................    29
         5.2  Pre-Phase III Development of Trap-2................................................................    29
         5.3  IL-1 Antibody Opt-In Rights........................................................................    30
         5.4  Trap-2 Opt-In Right................................................................................    31
         5.5  Grant of Co-Development Rights.....................................................................    31
         5.6  Co-Development of IL-1 Products....................................................................    33
         5.7  Co-Development Plans...............................................................................    33
         5.8  Co-Development Reports.............................................................................    33
         5.9  Loan Facilities for Trap-1 Product Development Costs...............................................    33

ARTICLE VI CO-COMMERCIALIZATION..................................................................................    38
         6.1  Grant of Co-Commercialization Rights...............................................................    38
         6.2  Exceptions to the Grant of Co-Commercialization Rights.............................................    39
         6.3  Commercialization of IL-1 Products in Co-Marketing Countries.......................................    39
         6.4  Commercialization of IL-1 Products in Co-Commercialization Countries...............................    40
         6.5  Co-Commercialization Plans.........................................................................    40
         6.6  Co-Commercialization Reports and Detailing Reports.................................................    41
         6.7  IL-1 Product Pricing and Pricing Approvals.........................................................    42
         6.8  Booking of Sales and IL-1 Product Distribution.....................................................    42
         6.9  Field Forces.......................................................................................    42
         6.10  Detailing.........................................................................................    43
</TABLE>

<PAGE>

                               TABLE OF CONTENTS
                                   (continue)

<TABLE>
<CAPTION>
                                                                                                                    Page
                                                                                                                    ----
<S>                                                                                                                 <C>
         6.11  Training..........................................................................................    45
         6.12  Promotional Materials.............................................................................    46
         6.13  Promotional Claims/Compliance.....................................................................    46
         6.14  Samples...........................................................................................    46
         6.15  Cost of Field Sales Promotion.....................................................................    47
         6.16  Managed Care and Institutional Customers..........................................................    47
         6.17  Shared Promotion Expenses.........................................................................    47
         6.18  Medical and Consumer Inquiries....................................................................    47
         6.19  Compliance with Laws..............................................................................    47
         6.20  Phase IV Clinical Trials..........................................................................    48
         6.21  Market Exclusivity Extensions.....................................................................    48
         6.22  Non-Compete.......................................................................................    48
         6.23  Loan Facility for Shared Promotion Expenses.......................................................    49

ARTICLE VII CLINICAL AND REGULATORY AFFAIRS......................................................................    51
         7.1  Ownership of Approvals and Registration Filings....................................................    51
         7.2  Regulatory Coordination............................................................................    51
         7.3  Regulatory Meetings................................................................................    52
         7.4  Regulatory Correspondence..........................................................................    52
         7.5  Assistance.........................................................................................    52
         7.6  Pharmacovigilance and Safety Data Exchange.........................................................    53

ARTICLE VIII MANUFACTURING AND SUPPLY............................................................................    53
         8.1  Supply of Clinical Supply Requirements for Trap-1 Product..........................................    53
         8.2  Supply of Commercial Requirements for Trap-1 Product...............................................    54
         8.3  Supply of Clinical Supply Requirements and Commercial Requirements for IL-1 Antibody Product.......    55
         8.4  Supply of Clinical Supply Requirements and Commercial Requirements for Trap-2 Product..............    55

ARTICLE IX PERIODIC REPORTS; PAYMENTS............................................................................    56
         9.1  Periodic Reports...................................................................................    56
         9.2  Funds Flow.........................................................................................    57
         9.3  Royalty............................................................................................    57
         9.4  Upfront Payments and Milestone Payments............................................................    58
         9.5  Revenue and Expenses in Co-Marketing Countries.....................................................    58
         9.6  Allocation of Costs and Expenses...................................................................    58
         9.7  Invoices and Documentation.........................................................................    58
         9.8  Payment Currency...................................................................................    58
         9.9  Late Payments......................................................................................    58
         9.10  Taxes.............................................................................................    59

ARTICLE X DISPUTE RESOLUTION.....................................................................................    59
         10.1  Resolution of Disputes............................................................................    59
         10.2  Arbitration of Legal Disputes.....................................................................    59
</TABLE>

                                      (ii)

<PAGE>

                                TABLE OF CONTENTS
                                   (continued)

<TABLE>
<CAPTION>
                                                                                                                    Page
                                                                                                                    ----
<S>                                                                                                                 <C>
ARTICLE XI TRADEMARKS AND CORPORATE LOGOS........................................................................    61
         11.1  Corporate Logos...................................................................................    61
         11.2  Selection of Product Trademarks...................................................................    61
         11.3  Ownership of Product Trademarks...................................................................    61
         11.4  Prosecution, Maintenance and Enforcement of Product Trademarks....................................    61
         11.5  License to the Trap-1 and Trap-2 Product Trademarks...............................................    62
         11.6  License to the IL-1 Antibody Product Trademark....................................................    62
         11.7  Use of Corporate Names............................................................................    63

ARTICLE XII NEWLY CREATED INVENTIONS.............................................................................    63
         12.1  Ownership of Newly Created Intellectual Property..................................................    63
         12.2  Prosecution and Maintenance of Patent Rights......................................................    64

ARTICLE XIII INTELLECTUAL PROPERTY LITIGATION....................................................................    65
         13.1  Third Party Infringement Suits....................................................................    65
         13.2  Patent Marking....................................................................................    66
         13.3  Third Party Infringement Claims...................................................................    66
         13.4  Amgen License.....................................................................................    67

ARTICLE XIV BOOKS, RECORDS AND INSPECTIONS; AUDITS AND ADJUSTMENTS...............................................    67
         14.1  Books and Records.................................................................................    67
         14.2  Audits and Adjustments............................................................................    67
         14.3  Accounting Standards..............................................................................    68

ARTICLE XV REPRESENTATIONS AND WARRANTIES........................................................................    68
         15.1  Due Organization, Valid Existence and Due Authorization...........................................    68
         15.2  Intellectual Property.............................................................................    68
         15.3  Disclaimer........................................................................................    69

ARTICLE XVI CONFIDENTIALITY......................................................................................    69
         16.1  Confidential Company Information..................................................................    69
         16.2  Injunctive Relief.................................................................................    70
         16.3  Publication of New Information....................................................................    70
         16.4  Other Publications................................................................................    71

ARTICLE XVII INDEMNITY...........................................................................................    71
         17.1  Indemnity and Insurance...........................................................................    71
         17.2  Indemnity Procedure...............................................................................    72

ARTICLE XVIII FORCE MAJEURE......................................................................................    72

ARTICLE XIX TERM AND TERMINATION.................................................................................    73
         19.1  Term..............................................................................................    73
         19.2  Expiration of Term................................................................................    73
         19.3  Termination By Mutual Agreement in Special Circumstances..........................................    74
         19.4  Termination Without Cause.........................................................................    75
</TABLE>

                                     (iii)

<PAGE>

                                TABLE OF CONTENTS
                                   (continued)

<TABLE>
<CAPTION>
                                                                                                                    Page
                                                                                                                    ----
<S>                                                                                                                 <C>
         19.5  Termination For Material Breach...................................................................    76
         19.6  Insolvency........................................................................................    77
         19.7  Termination for Change of Control.................................................................    77
         19.8  Effect of Termination for Material Breach, Insolvency, Change of Control
                 or Breach of Standstill Provisions..............................................................    78
         19.9  Survival of Obligations...........................................................................    78

ARTICLE XX MISCELLANEOUS.........................................................................................    79
         20.1  Governing Law.....................................................................................    79
         20.2  Waiver............................................................................................    79
         20.3  Notices...........................................................................................    79
         20.4  Entire Agreement..................................................................................    79
         20.5  Amendments........................................................................................    79
         20.6  Headings..........................................................................................    80
         20.7  Severability......................................................................................    80
         20.8  Registration and Filing of the Agreement..........................................................    80
         20.9  Assignment........................................................................................    80
         20.10  Successors and Assigns...........................................................................    80
         20.11  Counterparts.....................................................................................    80
         20.12  Third-Party Beneficiaries........................................................................    80
         20.13  Relationship of the Parties......................................................................    81
         20.14  Limitation of Damages............................................................................    81
         20.15  Non-Solicitation.................................................................................    81
         20.16  Hardship.........................................................................................    81
</TABLE>

                                      (iv)

<PAGE>

SCHEDULE 1         Target Profit Splits
SCHEDULE 2         Proportion of Detailing Efforts
SCHEDULE 3         Royalty
SCHEDULE 4         Shared Development Costs
SCHEDULE 5         Failure to Perform Details
SCHEDULE 6         Milestone Payments
SCHEDULE 7         Principles in Determining COGS
SCHEDULE 8         Preliminary Development Plan
SCHEDULE 9         First Consolidated Co-Development Budget
SCHEDULE 10        Non-Distributor Countries
SCHEDULE 11        Regulatory Tasks To Be Conducted By Novartis in U.S.
                   for Trap-1 and Trap-2
SCHEDULE 12        Procedures for Adverse Event and Other Safety Data
                   Exchange Notification and Reporting
SCHEDULE 13        Existing Licenses
SCHEDULE 14-18     [Intentionally Omitted]
SCHEDULE 19        Transition Arrangements
     Part A        Transition to Regeneron
     Part B        Transition to Novartis
SCHEDULE 20        Notices

EXHIBIT A          Form of Quality Agreement

                                      (v)

<PAGE>

                                                                   Exhibit 10.23

                   COLLABORATION, LICENSE AND OPTION AGREEMENT

         THIS COLLABORATION, LICENSE AND OPTION AGREEMENT ("Agreement"), dated
as of March 28, 2003 (the "Effective Date"), is by and between NOVARTIS PHARMA
AG, a corporation organized under the laws of Switzerland and having a principal
place of business at Lichtstrasse 35, 4056 Basel, Switzerland ("Novartis"),
NOVARTIS PHARMACEUTICALS CORPORATION of One Health Plaza, East Hanover, New
Jersey ("NPC") and REGENERON PHARMACEUTICALS, INC., a corporation organized
under the laws of New York and having a principal place of business at 777 Old
Saw Mill River Road, Tarrytown, New York 10591 ("Regeneron") (with each of
Novartis and Regeneron referred to herein individually as a "Party" and
collectively as the "Parties" and with NPC being a party to this Agreement for
purposes of Section 9.4(a) only).

         WHEREAS, Regeneron has certain rights in the applicable Territories in
and to certain interleukin-1 trap molecules, and Regeneron intends to develop
and commercialize the Trap-1 Product;

         WHEREAS, Regeneron wishes to cooperate with another entity which
provides expertise in the development, manufacture and commercialization of
pharmaceutical products to Co-Develop, to manufacture and to Co-Commercialize
and, in certain circumstances, Co-Market, the Trap-1 Product to Professionals,
customers and the general public in certain countries in the Trap-1 Territory
during the applicable Term;

         WHEREAS, Novartis and its Affiliates possess expertise in developing,
manufacturing and commercializing pharmaceutical products and has in place large
and experienced regulatory and marketing teams;

         WHEREAS, the Parties contemplate that enhanced sales resulting in
mutual advantage may be realized by utilizing such expertise and Know-How of
Novartis and its Affiliates and wish to Co-Develop and Co-Commercialize and, in
certain circumstances, Co-Market, the Trap-1 Product to Professionals, customers
and the general public in certain countries in the Trap-1 Territory during the
applicable Term;

         WHEREAS, Novartis and its Affiliates have certain rights in the
applicable Territory in and to certain anti-interleukin-1 antibodies, and
Novartis and certain of its Affiliates intend to develop, manufacture and
commercialize the IL-1 Antibody Product;

         WHEREAS, Novartis and its Affiliates are developing the
anti-interleukin-1 antibodies known as AAL and ACZ;

         WHEREAS, Novartis and its Affiliates wish to grant to Regeneron, and
Regeneron wishes to accept, the right to elect to share in the Development and
Commercialization of the IL-1 Antibody Product;

         WHEREAS, Regeneron is also developing an interleukin-1 trap product,
known as Trap-2; and

         WHEREAS, Regeneron wishes to grant to Novartis and its Affiliates, and
Novartis and its Affiliates wish to accept, the right to elect to share in the
Development and Commercialization of the Trap-2 Product.

<PAGE>

         NOW, THEREFORE, in consideration of the following mutual promises and
obligations, and for other good and valuable consideration the adequacy and
sufficiency of which are hereby acknowledged, the Parties agree as follows:

                                    ARTICLE I

                                   DEFINITIONS

         Capitalized terms used in this Agreement, whether used in the singular
or plural, except as expressly set forth herein, shall have the meanings set
forth below:

         "AAL" shall mean [***********************************************]
which is being Developed by Novartis and its Affiliates as at the Effective
Date.

         "ACZ" shall mean [*********************************************]which
is being Developed by Novartis and its Affiliates as at the Effective Date.

         "Adverse Reaction Reports" shall have the meaning set forth in Section
7.6(b).

         "Affiliate" shall mean, with respect to any Person, any other Person
which controls, is controlled by or is under common control with such Person. A
Person shall be deemed to control another Person if such Person possesses,
directly or indirectly, the power to direct or cause the direction of the
management and policies of such Person, whether through the ownership of voting
securities, by contract or otherwise. For purposes of this Agreement, in no
event shall Novartis or any of its Affiliates be deemed Affiliates of Regeneron
or any of its Affiliates nor shall Regeneron or any of its Affiliates be deemed
Affiliates of Novartis or any of its Affiliates.

         "Agreement" shall have the meaning set forth in the introductory
paragraph, including all Schedules.

         "Alliance Manager" shall have the meaning set forth in Section 3.6.

         "Allocable Overhead" shall have the meaning set forth in SCHEDULE 7.

         "Alternate Marketing Channels" shall mean promotional services such as
telemarketing, peer meetings, medical symposia, direct mail, internet marketing
and electronic detailing, and other legally accepted promotional activities,
whether directed to Professionals, customers or the public at large.

         "Amgen License Agreement" shall mean the License Agreement dated as of
June 26, 2002 among Amgen Inc., Immunex Corporation, and Regeneron, as it may be
amended from time to time, a true and correct copy of which has previously been
delivered to Novartis.

         "Ancillary Agreement" shall mean any other agreement between the
Parties pertaining to the Co-Development, production, technology transfer,
and/or Co-Commercialization of IL-1 Products in the Co-Commercialization
Countries during the applicable Term, which agreement shall have been expressly
designated by the Parties as an "Ancillary Agreement" for purposes hereof.

         "Annual Net Sales" shall mean, with respect to an IL-1 Product, Net
Sales of such IL-1 Product during any Contract Year.

                                      -2-

<PAGE>

         "Approval" shall mean, with respect to each IL-1 Product, any approval
(excluding Pricing Approvals), registration, license or authorization from any
Regulatory Authority required for the manufacture, Development,
Co-Commercialization, sale, storage or transport of such IL-1 Product in any
Co-Commercialization Country, and shall include, without limitation, an
approval, registration, license or authorization granted in connection with any
Registration Filing.

         "BLA" shall mean, with respect to each IL-1 Product, a biologics
license application filed with respect to such IL-1 Product, as described in the
FDA regulations, including all amendments and supplements to the application,
and any equivalent filing with any Regulatory Authority.

         "Business Day" shall mean any day other than a Saturday, a Sunday or a
day on which commercial banks in New York, USA, or Basel, Switzerland, are
authorized or required by Law to remain closed.

         "Change of Control" shall mean, with respect to either Party, any of
the following events: (i) any Person is or becomes the "beneficial owner" (as
such term is used in Sections 12(d) and 13(d) of the Securities Exchange Act of
1934, as amended, except that a Person shall be deemed to have "beneficial
ownership" of all shares that any such Person has the right to acquire, whether
such right which may be exercised immediately or only after the passage of
time), directly or indirectly, of a majority of the total voting power
represented by all classes of capital stock then outstanding of such Party
normally entitled to vote in elections of directors; (ii) such Party
consolidates with or merges into another corporation or entity, or any
corporation or entity consolidates with or merges into such Party, other than
(A) a merger or consolidation which would result in the voting securities of
such Party outstanding immediately prior to such merger or consolidation
continuing to represent (either by remaining outstanding or by being converted
into voting securities of the surviving entity or any parent thereof) a majority
of the combined voting power of the voting securities of such Party or such
surviving entity or any parent thereof outstanding immediately after such merger
or consolidation, or (B) a merger or consolidation effected to implement a
recapitalization of such Party (or similar transaction) in which no Person
becomes the beneficial owner, directly or indirectly, of voting securities of
such Party representing a majority of the combined voting power of such Party's
then outstanding securities; or (iii) such Party conveys, transfers or leases
all or substantially all of its assets to any Person other than a wholly-owned
Affiliate of such Person.

         "Clinical Supply Cost" shall mean, with respect to Clinical Supply
Requirements of a particular IL-1 Product, the manufacturing Party's Fully
Burdened Manufacturing Cost (in this instance the definition of Fully Burdened
Manufacturing Cost shall apply to Regeneron as a manufacturing party as well)
for the particular IL-1 Product.

         "Clinical Supply Requirements" shall mean the quantities of any IL-1
Product which are required by a Party or the Parties for the conduct of
preclinical studies and Clinical Trials in connection with a Consolidated
Co-Development Plan in order to obtain Approval of such IL-1 Product in any
country in an applicable Territory and quantities of any IL-1 Product which are
required by a Party for submission to a Regulatory Authority in connection with
any Registration Filing or Approval in any country in an applicable Territory.

                                      -3-

<PAGE>

         "Clinical Trial" shall mean a Phase I Clinical Trial, Phase I/IIA
Clinical Trial, Phase IIA Clinical Trial, Phase IIB Clinical Trial, Phase III
Clinical Trial, Phase IIIB Clinical Trial, Phase IV Clinical Trial or
combination thereof.

         "Co-Brand" or "Co-Branding" shall mean, with respect to an IL-1
Product, in an applicable territory the marketing and promotion of such IL-1
Product under separate and distinct trademarks by each Party or its Affiliates
in a Co-Branding Country pursuant to the applicable Country Co-Commercialization
Plan, and where both brands are distributed and sold in such Co-Branding Country
only by Novartis or its Affiliates.

         "Co-Branding Country" shall mean each country in the applicable
Territory in which Co-Promotion of IL-1 Products is not permitted under local
Law and Co-Marketing is not required under local Law.

         "Co-Commercialize" or "Co-Commercialization" shall mean Co-Branding and
Co-Promoting, as defined in this Article I.

         "Co-Commercialization Country" shall mean each Co-Promotion Country and
Co-Branding Country in the applicable Territory.

         "Co-Commercialization Provisions" shall have the meaning set forth in
Section 6.1(c).

         "Co-Development" shall mean the joint Development of IL-1 Products by
the Parties, as described in Sections 5.5 to 5.8 inclusive, following: (a) the
Effective Date with respect to Trap-1 Products; (b) the proper exercise of the
IL-1 Antibody Opt-In Rights, with respect to IL-1 Antibody Products; and (c) the
proper exercise of the Trap-2 Opt-In Rights, with respect to Trap-2 Products,
and "Co-Develop" shall have a corresponding meaning.

         "COGS" or "Cost of Goods Sold" shall mean, with respect to each IL-1
Product, the price of such IL-1 Product as agreed between the Parties pursuant
to Section 8.2(a) and in accordance with the principles set forth in SCHEDULE 7
hereto.

         "Collaboration Matters" shall have the meaning set forth in Section
3.1(c).

         "Collaboration Purpose" shall have the meaning set forth in Section
3.1(b).

         "Co-Market" or "Co-Marketing" shall mean, with respect to an IL-1
Product, the separate marketing and sale in a Co-Marketing Country of such IL-1
Product under separate and distinct trademarks.

         "Co-Marketing Country" shall mean each country in the applicable
Territory in which Co-Promotion and Co-Branding are not permitted under local
Law, but in which Co-Marketing is permitted under local Law.

         "Commercial Requirements" shall mean such quantities of any IL-1
Product as are required by a Party or the Parties to fulfill such Party's or
Parties' commercial sales requirements with respect to such IL-1 Product in the
applicable Territory.

         "Commercialize" or "Commercialization" shall mean any and all
activities directed to marketing, promoting, distributing, importing, offering
for sale and/or selling an IL-1 Product, including pre-marketing (including
market research and analysis, and health

                                      -4-

<PAGE>

economics), sampling, post-marketing drug surveillance and conducting Phase IIIB
Clinical Trials and Phase IV Clinical Trials, other than those intended to
support or maintain a Registration Filing for the particular IL-1 Product
(including by way of example to support expanded labeling for such IL-1 Product
or to satisfy requirements imposed by Regulatory Authorities in connection with
Approvals for such IL-1 Product).

         "Commercially Reasonable Efforts" shall mean, with respect to the
efforts to be expended by a Party with respect to any objective, reasonable,
diligent, good faith efforts to accomplish such objective as such Party would
normally use to accomplish a similar objective under similar circumstances, it
being understood and agreed that with respect to the research, manufacture,
Development or Commercialization of any IL-1 Product, such efforts shall be
consistent with the Collaboration Purpose and substantially equivalent to those
efforts and resources commonly used by a Party for a product owned by it, which
product is at a similar stage in its development or product life and is of
similar market potential taking into account efficacy, safety, approved
labeling, the competitiveness of alternative products in the marketplace (for
this purpose treating another IL-1 Product as if it were owned by a Third
Party), the patent and other proprietary position of the product, the likelihood
of Approval given the regulatory structure involved, the profitability of the
product, alternative products (for this purpose, treating another IL-1 Product
as if it were owned by a Third Party) and other relevant factors. Commercially
Reasonable Efforts shall be determined on a market-by-market and
product-by-product basis, and it is anticipated that the level of effort will
change over time, reflecting changes in the status of the Parties, the
particular IL-1 Product and the market(s) involved. In evaluating "market
potential," neither Party shall consider the profit sharing, milestone or other
payments payable under this Agreement to the other Party.

         "Committee" means any of the JSC and the JOC each as defined in this
Article I and described in Article III (together with any other committee or
sub-committee contemplated hereby or established in accordance with this
Agreement or any Ancillary Agreement).

         "Company Information" shall mean information or materials provided in
connection with this Agreement or any Ancillary Agreement by either Novartis or
Regeneron or their respective Affiliates to the other Party or its Affiliates,
including, without limitation, by disclosure to any Committee, whether furnished
before or after the Effective Date, including, without limitation, information
and materials in relation to research, development, manufacturing, promotion,
marketing, distributing and selling of IL-1 Products hereunder, and information
and materials on substances, formulations, techniques, technology, equipment,
data, reports, Know-How, sources for supply, patent position, business plans,
sales management procedures and other general business and operational processes
and procedures.

         "Competing Product" shall mean
[****************************************].

         "Consolidated Co-Commercialization Budget" shall mean, with respect to
an IL-1 Product, the global annual budget(s) for all Co-Commercialization
Countries as set forth in the Consolidated Co-Commercialization Plan approved by
the Joint Steering Committee.

         "Consolidated Co-Commercialization Plan" shall mean, with respect to an
IL-1 Product, each annual global Co-Commercialization plan for such IL-1 Product
approved by the Joint Steering Committee, including the related Consolidated
Co-Commercialization

                                      -5-

<PAGE>

Budget, for the Co-Commercialization Countries, which shall include, inter alia,
the total number of PDEs to be conducted by the Parties or their relevant
Affiliates.

         "Consolidated Co-Commercialization Report" shall mean, with respect to
an IL-1 Product, a written report setting forth in reasonable detail the
marketing and promotional activities (other than PDEs) undertaken by the
reporting Party and its Affiliates during the previous quarter in connection
with the Consolidated Co-Commercialization Plan, together with a detailed
project-level statement of Shared Promotion Expenses incurred by such quarter,
including any necessary adjustments for previous quarters.

         "Consolidated Co-Development Budget" shall mean, with respect to an
IL-1 Product, the budget(s) approved by the Joint Steering Committee for the
applicable Territory included in the Consolidated Co-Development Plan; provided,
however, that
[*************************************************************************].

         "Consolidated Co-Development Plan" shall mean, with respect to an IL-1
Product, each annual global Co-Development Plan for such IL-1 Product approved
by the Joint Steering Committee, including the related Consolidated
Co-Development Budget for the applicable Territory. With respect to the period
from January 1, 2003 through December 31, 2003, the Preliminary Development Plan
shall serve as the Consolidated Co-Development Plan, and the budget set forth as
SCHEDULE 9 shall serve as the Consolidated Co-Development Budget, for such
period.

         "Consolidated Net Sales and Expense Report" shall mean, with respect to
each IL-1 Product, a consolidated quarterly report prepared by Novartis setting
forth in detail for each Region within the applicable Territory, the aggregate
Net Sales, COGS, Shared Promotion Expenses and Development Costs in the
Co-Commercialization Countries in such Region.

         "Contract Sales Force" shall mean the services of sales representatives
employed by a Third Party.

         "Contract Year" shall mean the period beginning on the Effective Date
and ending on December 31, 2003, and each succeeding twelve (12) month period
thereafter during the Term.

         "Controlling Party" shall mean, with respect to the filing, prosecution
and maintenance of a Joint Patent Right, Novartis, in the case of a Joint Patent
Right that primarily relates to an IL-1 Antibody Product, and Regeneron, in the
case of a Joint Patent Right that primarily relates to a Trap-1 Product or a
Trap-2 Product.

         "Co-Promote" or "Co-Promotion" shall mean, with respect to an IL-1
Product, the joint marketing and promotion of such IL-1 Product by the Parties
(or their respective Affiliates), under the same trademark in each Co-Promotion
Country pursuant to the applicable Country Co-Commercialization Plan, and the
distribution and sale of such IL-1 Product in such Co-Promotion Country solely
by Novartis or its Affiliates.

         "Co-Promotion Country" shall mean each country included in the
applicable Territory, other than the Co-Branding Countries and the Co-Marketing
Countries.

         "Country Co-Commercialization Budget" shall mean the budget(s) included
in a Country Co-Commercialization Plan for a particular Co-Commercialization
Country.

                                      -6-

<PAGE>

         "Country Co-Commercialization Plan" shall mean the plan(s), including
the related Country Co-Commercialization Budget, developed by the JOC or the
applicable Joint Country Commercialization Sub-Committee (if any) for a
particular Co-Commercialization Country, the main elements of which will be
included in a Consolidated Co-Commercialization Plan approved by the JSC.

         "Country Co-Commercialization Report" shall mean, with respect to an
IL-1 Product, a written report setting forth in reasonable detail the marketing
and promotional activities (other than PDEs) undertaken by a Party (or its
relevant local Affiliates) during the previous quarter in connection with the
applicable Country Co-Commercialization Plan, together with a detailed
project-level statement of Shared Promotion Expenses incurred by such Party
during such quarter in such Co-Commercialization Country, including any
necessary adjustments for previous quarters.

         "Country Net Sales and Expense Report" shall mean, with respect to each
IL-1 Product and each Co-Commercialization Country, a report prepared by
Novartis setting forth the aggregate Net Sales, COGS, Shared Promotion Expenses
and Development Costs with respect to such IL-1 Product in such
Co-Commercialization Country in local currency.

         "Damages" shall have the meaning set forth in Section 17.1(a).

         "Default Interest Rate" shall have the meaning set forth in Section
9.9.

         "Detail" or "Detailing" shall mean a face-to-face meeting in an
individual or group practice setting, between a Qualified Sales Representative
of a Party or its Affiliate, on the one hand, and a Professional, on the other
hand, during which a Primary Product Presentation or a Secondary Product
Presentation is made to such Professional relating to an IL-1 Product; provided
that such meeting is generally consistent with and in accordance with the
procedures and policies customarily employed by such Party's sales force
responsible for performing such activities for the majority of its other major
marketed pharmaceutical products (if any).

         "Detailing Report" shall have the meaning set forth in Section 6.6.

         "Develop" or "Development" shall mean (a) preclinical and clinical drug
development activities, including, without limitation, test method development
and stability testing, assay development and audit development, toxicology,
formulation, quality assurance/quality control development, statistical
analysis, Clinical Trials (except for Phase IIIB Clinical Trials and Phase IV
Clinical Trials conducted for purposes other than to support or maintain a
Registration Filing for the particular IL-1 Product, including by way of example
to support expanded labeling for such IL-1 Product or to satisfy requirements
imposed by Regulatory Authorities in connection with Approvals for such IL-1
Product) and regulatory affairs, product approval and registration and (b)
research and development of the applicable drug products and drug substances.

         "Development Costs" shall mean, with respect to any IL-1 Product,
expenses and other costs, including Regulatory Expenses, incurred by or on
behalf of a Party in connection with the Development of such IL-1 Product in
accordance with the applicable approved Consolidated Co-Development Plan and
Consolidated Co-Development Budget, including, without limitation, the costs of
Clinical Trials, the preparation, collation and/or validation of data from such
Clinical Trials and the preparation of medical writing and publishing;

                                      -7-

<PAGE>

provided that Development Costs shall include the cost of Phase IIIB Clinical
Trials and Phase IV Clinical Trials only if they are intended to support or
maintain a Registration Filing for the particular IL-1 Product (including by way
of example to support expanded labeling for such IL-1 Product, or to satisfy
requirements imposed by Regulatory Authorities in connection with Approvals for
such IL-1 Product). Without limitation of the generality of the foregoing,
Development Costs shall include:

                  (a)      all Out-of-Pocket Costs incurred by the Parties or
         their Affiliates, including payments made to Third Parties with respect
         to any of the foregoing;

                  (b)      the full personnel cost of internal scientific and
         technical personnel engaged in such efforts, which costs shall be
         determined based on the FTE Rate or such other basis as may otherwise
         be agreed by the Parties;

                  (c)      the costs of Clinical Supply Requirements (including,
         without limitation, Clinical Supply Costs) for such efforts as agreed
         in the applicable approved Consolidated Co-Development Plan;

                  (d)      the costs and expenses incurred in connection with
         formulation development, manufacturing process development and
         validation, manufacturing scale-up and start-up, stability testing and
         quality assurance/quality control development (in each case, to the
         extent not included in COGS); and

                  (e)      any other costs or expenses included in the
         applicable Consolidated Co-Development Budget contained in the
         applicable approved Consolidated Co-Development Plan.

Notwithstanding any other provision of this Agreement, Development Costs shall
not include any costs or expenses incurred prior to: (i) January 1, 2003 (other
than Clinical Supply Costs incurred in 2002 relating to Phase IIB Clinical
Trials ongoing in 2003); (ii) the proper exercise of the IL-1 Antibody Opt-In
Rights by Regeneron, with respect to Development of IL-1 Antibody Products; or
(iii) the proper exercise of the Trap-2 Opt-In Rights by Novartis, with respect
to Development of Trap-2 Products.

         "Distributor" shall mean any Third Party contractually engaged by
Novartis to market and/or sell the IL-1 Product in the relevant
Co-Commercialization Country, where the cost of such Third Party's services is
not greater than that set forth in the applicable Country Co-Commercialization
Budget included in the applicable Country Co-Commercialization Plan.

         "EMEA" shall mean the European Medicines Evaluation Agency or any
successor agency thereto.

         "End of Phase II Development" shall mean the date on which the final
report becomes available following completion of the first Phase IIB Clinical
Trial (or Phase IIA Clinical Trial if such Clinical Trial is the Clinical Trial
immediately preceding initiation of a Phase III Clinical Trial) for the IL-1
Antibody or Trap-2, as applicable, regardless of the indication for which such
Phase IIB Clinical Trial is conducted.

         "EU" shall mean the European Union Member States, as they exist from
time to time, comprising, as of the Effective Date, Austria, Belgium, Denmark,
Finland, France, Germany, Greece, Ireland, Italy, Luxembourg, The Netherlands,
Portugal, Spain, Sweden and the

                                      -8-

<PAGE>

United Kingdom, and in any event, including at a minimum, Germany, France and
the United Kingdom.

         "Europe" shall mean every country in the EU and Switzerland.

         "Exclusive Country" shall mean each country agreed between the Parties
pursuant to Section 6.2(b), if any.

         "Effective Date" shall have the meaning set forth in the introductory
paragraph.

         "Executive Officers" shall mean the Chief Executive Officer of
Regeneron and the Chief Executive Officer of Novartis.

         "Existing Licenses" shall mean the agreements listed in SCHEDULE 13.

         "FDA" shall mean the United States Food and Drug Administration and any
successor agency thereto.

         "Final Approval" shall mean, with respect to any IL-1 Product: (a) in
relation to the United States, receipt of the official approval letter from the
FDA approving the BLA, with respect to such IL-1 Product or any supplemental
BLA, as applicable; and (b) in relation to any country in Europe, receipt of the
written decision of the appropriate Regulatory Authority granting marketing
authorization for such IL-1 Product.

         "First Commercial Sale" shall mean, with respect to an IL-1 Product in
a country, the first sale of such IL-1 Product by a Party or one of its
Affiliates or sublicensees to a Third Party in accordance with the applicable
Laws of such country on arm's length commercial terms which are reasonably
expected to be substantially similar to future terms of sale of such IL-1
Product to Third Parties for commercial use by patients in such country. Sales
for test marketing, Clinical Trial purposes or compassionate or similar use
shall not be considered to constitute a First Commercial Sale.

         "Force Majeure" shall have the meaning set forth in Article XVIII.

         "FTC" means the United States Federal Trade Commission.

         "FTE" shall mean a full-time equivalent person year
(***********************) of scientific, technical or managerial work on studies
or activities performed in accordance with the applicable Consolidated
Co-Development Plan, in connection with obtaining Approvals for the IL-1
Products or, in certain circumstances, its connection with the Commercialization
of an IL-1 Product.

         "FTE Rate" shall mean (a) [*****************************************]
per FTE and (b) thereafter, shall be as agreed (i) by the JOC with respect to
global Development and Commercialization activities, and (ii) by the applicable
Country Co-Commercialization Committee (if any, and otherwise by the JOC), on a
country-by-country basis with respect to Development and Commercialization
activities in such Co-Commercialization Country.

         "Fully Allocated Costs" shall mean, with respect to an activity, all
direct and indirect costs and overhead allocable to the conduct of such activity
in accordance with GAAP or IAS, as applicable (depending on how the entity
conducting such activity maintains its accounting books and records), including,
without limitation, costs of raw materials, supplies,

                                      -9-

<PAGE>

other resources consumed in the conduct of such activity, rent, real estate
depreciation, utilities, insurance, equipment lease payments, equipment
depreciation and labor.

         "Fully Burdened Manufacturing Costs" shall have the meaning set forth
in SCHEDULE 7.

         "GAAP" shall mean generally accepted accounting principles in the
United States.

         "Global Harmonized Clinical Trial Guidelines" shall mean the
guidelines, applicable to pre-clinical trials and Clinical Trials, which are
developed by the ICH, as enacted in Law by ICH member countries and those
adherent countries which are not formal parties to the ICH but which adhere to
the tenets of the ICH process in whole or in part.

         "Good Practices" shall mean compliance with the applicable standards
contained in then-current "Good Laboratory Practices," "Good Manufacturing
Practices" and/or "Good Clinical Practices," as promulgated by the FDA and all
analogous guidelines promulgated by the EMEA or the ICH.

         "Governmental Authority" shall mean any court, agency, authority,
department, regulatory body or other instrumentality of any government or
country or of any national, federal, state, provincial, regional, county, city
or other political subdivision of any such government or any supranational
organization of which any such country is a member.

         "ICC Court" shall have the meaning set forth in Section 10.2(b).

         "ICH" shall mean the International Conference on Harmonization of
Technical Requirements for Registration of Pharmaceuticals for Human Use.

         "IL-1" means the cytokine, interleukin-1.

         "IL-1 Antibody" shall mean [************************************] and
which shall be subject to the IL-1 Antibody Opt-In Rights.

         "IL-1 Antibody Opt-In Payment" shall mean:
[******************************].

         "IL-1 Antibody Opt-In Rights" shall mean the rights set forth in
Section 5.3.

         "IL-1 Antibody Product" shall mean one or more pharmaceutical products
for human and/or animal use which include the IL-1 Antibody as an active
ingredient, alone or in combination with one or more other active ingredients,
for all indications.

         "IL-1 Antibody Territory" shall mean NAFTA.

         "IL-1 Products" shall mean: (a) any Trap-1 Product; and (b) in the
event that Novartis properly exercises the Trap-2 Opt-In Rights, any Trap-2
Product; and (c) in the event that Regeneron properly exercises the IL-1
Antibody Opt-In Rights, any IL-1 Antibody Product in each case, subject to
Article XIX (including SCHEDULE 19), for so long as this Agreement has not been
terminated with respect to such IL-1 Product.

         "IND" shall mean an Investigational New Drug Application filed with the
FDA.

         "Indemnified Party" shall have the meaning set forth in Section
17.2(a).

                                      -10-

<PAGE>

         "Indemnifying Party" shall have the meaning set forth in Section
17.2(a).

         "International Accounting Standards" or "IAS" shall mean international
accounting standards (IAS), as published from time to time by the International
Accounting Standards Committee.

         "IPSC" shall have the meaning set forth in Section 3.1(a).

         "Joint Invention" shall have the meaning set forth in Section 12.1(b).

         "Joint Operating Committee" or "JOC" shall mean the Joint Operating
Committee, as described in Section 3.4.

         "Joint Patent Rights" shall mean Patent Rights that cover a Joint
Invention.

         "Joint Steering Committee" or "JSC" shall mean the Joint Steering
Committee, as described in Section 3.2.

         "Know-How" shall mean any and all proprietary technical information,
know-how, data, test results, knowledge, techniques, discoveries, inventions,
specifications, designs, trade secrets, regulatory filings, and other
information (whether or not patentable) which are now or hereafter during the
term of this Agreement owned by, licensed to or otherwise held by a Party or its
Affiliates with the rights to license or sublicense the same and that relate to
an IL-1 Product or the Development, manufacture, use, offer for sale or sale
thereof.

         "Launch" shall mean, with respect to an IL-1 Product in a country, the
First Commercial Sale of such IL-1 Product in such country after receipt of all
required Approvals, and, if applicable, Pricing Approval and import approval.

         "Law" or "Laws" shall mean all laws, statutes, rules, regulations,
orders, judgments, injunctions and/or ordinances of any Governmental Authority
in the applicable Territory.

         "Lead Regulatory Party" shall mean, with respect to each IL-1 Product,
whichever of Novartis or Regeneron has been designated hereunder as having
responsibility for preparing, prosecuting and maintaining Approvals and
Registration Filings relating to such IL-1 Product, and for related regulatory
duties.

         "Legal Dispute" shall mean any dispute, controversy or claim related to
compliance with this Agreement or any Ancillary Agreement or the validity,
breach, termination or interpretation of this Agreement or any Ancillary
Agreement, but shall not include any matter to be determined pursuant to Article
III, except to the extent such matter constitutes a dispute, controversy or
claim related to compliance, with or the validity, breach, termination or
interpretation of any provision of Article III.

         "Managed Care and Institutional Customers" shall mean managed care,
long-term care, senior care, health system, hospital, group purchasing,
government and physician similar practice group customers in the
Co-Commercialization Countries, together with such other types of similar
customers as may be agreed by the JOC from time to time on a country-by-country
basis.

         "Market Exclusivity Period" shall mean, with respect to each IL-1
Product in each Co-Commercialization Country, that period of time during which
(a) a Party(ies) has the

                                      -11-

<PAGE>

exclusive legal right, whether by means of a Patent Right or through other
rights granted by a Governmental Authority in such country, to market, price and
sell such IL-1 Product in such country, and (b) no generic equivalent of such
IL-1 Product is marketed in such country.

         "NAFTA" shall mean the United States, Canada and Mexico.

         "Net Sales" shall mean, with respect to an IL-1 Product, the gross
invoiced sales price of such IL-1 Product billed by or on behalf of Novartis or
its Affiliates to Third Parties on sales of an IL-1 Product in bona fide arm's
length transactions in the Co-Commercialization Countries, less the following
deductions, determined in accordance with Novartis' standard accounting methods
as generally and consistently applied by Novartis, to the extent included in the
gross invoiced sales price for such IL-1 Product or otherwise directly paid or
incurred by such Novartis, its Affiliates or Distributors with respect to the
sale of such IL-1 Product:

                  (a)      normal and customary trade and quantity discounts
         actually allowed and properly taken directly with respect to sales of
         such IL-1 Product;

                  (b)      amounts repaid or credited by reason of defects,
         rejections, recalls, returns, rebates and allowances;

                  (c)      chargebacks and other amounts paid on sale or
         dispensing of such IL-1 Product;

                  (d)      Third Party cash rebates and chargebacks related to
         sales of the finished IL-1 Product, to the extent allowed;

                  (e)      retroactive price reductions that are actually
         allowed or granted;

                  (f)      tariffs, duties, excise, sales, value-added or other
         taxes (other than taxes based on income);

                  (g)      cash discounts for timely payment;

                  (h)      delayed ship order credits;

                  (i)      discounts pursuant to indigent patient programs and
         patient discount programs, including, without limitation,
         [**********************];

                  (j)      [*********************************************]; and

                  (k)      any other specifically identifiable costs or charges
         included in the gross invoiced sales price of such IL-1 Product falling
         within categories substantially equivalent to those listed above.

Sales from Novartis to its Affiliates shall be disregarded for purposes of
calculating Net Sales. Any of the items set forth above that would otherwise be
deducted from the invoice price in the calculation of Net Sales but which are
separately charged to Third Parties shall not be deducted from the invoice price
in the calculation of Net Sales. In the case of any sale of an IL-1 Product for
consideration other than cash, such as barter or countertrade, Net Sales shall
be calculated on the fair market value of the consideration received as agreed
by the Parties. In the event that any IL-Product includes one or more active
ingredients other than Trap-1, Trap-2 or the IL-1 Antibody, then, prior to
Launch of such IL-1 Product, the Parties

                                      -12-

<PAGE>

shall agree, through the JSC, the appropriate method for accounting for sales of
such IL-1 Product. All discounts, credits, rebates, reductions, chargebacks, and
similar deductions described above shall be consistent with policies and
parameters approved in advance by the JSC or the applicable Country
Co-Commercialization Committee, if any.

         "New Information" shall mean any and all ideas, inventions, writings,
discoveries, improvements, not generally known to the public, which may arise or
be conceived or developed by either Party or jointly during the term of this
Agreement which relates to any IL-1 Product.

         "New License" shall mean any license, other than Existing Licenses,
required for the manufacture, Development or Commercialization of any IL-1
Product and approved by the Intellectual Property Sub-Committee.

         "Novartis" shall have the meaning set forth in the introductory
paragraph.

         "Novartis Intellectual Property" shall mean the Novartis Patent Rights
and any Know-How of Novartis or any of its Affiliates.

         "Novartis Patent Rights" shall mean those Patent Rights which are owned
by or licensed (with the right of sublicense) to Novartis or any of its
Affiliates (other than pursuant to this Agreement or any Ancillary Agreement)
and which include at least one claim which would be infringed by the
manufacture, use, sale, offer for sale or import of an IL-1 Product at any time
during the applicable Term for such IL-1 Product.

         "Novartis Sole Inventions" shall have the meaning set forth in Section
12.1(a).

         "Out-of-Pocket Costs" shall mean costs and expenses paid to Third
Parties (or payable to Third Parties and accrued in accordance with GAAP or IAS)
by either Party and/or its Affiliates.

         "Party" or "Parties" shall have the meaning set forth in the
introductory paragraph.

         "Patent Application" shall mean any application for a Patent.

         "Patent Rights" shall mean unexpired Patents and Patent Applications.

         "Patents" shall mean patents and all substitutions, divisions,
continuations, continuations-in-part, reissues, reexaminations and extensions
thereof and supplemental protection certificates relating thereto, and all
counterparts thereof in any country.

         "PDE" shall mean, unless otherwise specified in a Country
Co-Commercialization Plan or Consolidated Co-Commercialization Plan, a primary
detail equivalent which is [***************************************].

         "Person" shall mean and include an individual, partnership, joint
venture, limited liability company, a corporation, a firm, a trust, an
unincorporated organization and a government or other department or agency
thereof.

         "Phase I Clinical Trial" shall mean a clinical study of an IL-1 Product
in human volunteers with the endpoint of determining initial tolerance, safety
and/or pharmacokinetic

                                      -13-

<PAGE>

information in single dose, single ascending dose, multiple dose and/or multiple
ascending dose regimens.

         "Phase I/IIA Clinical Trial" shall mean (a) a Phase I Clinical Trial
and a Phase IIA Clinical Trial, collectively, or (b) a single clinical study
meeting the requirements of a Phase I Clinical Trial and a Phase IIA Clinical
Trial.

         "Phase IIA Clinical Trial" shall mean a clinical study of an IL-1
Product in patients to determine initial dose ranging tolerability and safety in
single dose, single ascending dose, multiple dose and/or multiple ascending dose
regimens.

         "Phase IIB Clinical Trial" shall mean a clinical study of an IL-1
Product in patients to definitively determine appropriate dose ranging
tolerability and safety.

         "Phase III Clinical Trial" shall mean a clinical study in patients
which protocol is designed to ascertain efficacy and safety of an IL-1 Product
for the purpose of preparing and submitting a Registration Filing to the
competent Regulatory Authority in a particular country in the applicable
Territory.

         "Phase IIIB Clinical Trial" shall mean a Phase III Clinical Trial
commenced before receipt of Approval in the jurisdiction where such trial is
being conducted, but which is not required for receipt of Approval and is
conducted primarily for the purpose of IL-1 Product support (i.e., providing
additional drug profile data).

         "Phase IV Clinical Trial" shall mean a clinical study initiated in a
country after receipt of Final Approval for an IL-1 Product in such country.

         "Plan" shall mean any Consolidated Co-Commercialization Plan, any
Country Co-Commercialization Plan, any Consolidated Co-Development Plan or other
plan approved through the Committee process relating to the Co-Development or
Co-Commercialization of an IL-1 Product under this Agreement.

         "Preliminary Development Plan" shall have the meaning set forth in
Section 5.7.

         "Prescription Drug Marketing Act" or "PDMA" shall mean the Prescription
Drug Marketing Act of 1987, as amended from time to time.

         "Pricing Approval" shall mean such approval, agreement, determination
or governmental decision establishing prices for an IL-1 Product that can be
charged to consumers and will be reimbursed by Governmental Authorities in
countries in the applicable Territory where governmental authorities or
Regulatory Authorities of such country approve or determine pricing for
pharmaceutical products for reimbursement or otherwise.

         "Primary Product Presentation" shall mean a full product presentation
during a call in which key messages related to an IL-1 Product are presented in
the first position and in a balanced manner consistent with the terms of this
Agreement, and [****************].

         "Product Trademark" shall mean, with respect to each IL-1 Product, the
trademark selected by the JSC for use on such IL-1 Product and/or accompanying
logos, trade dress and/or indicia of origin, in each case as selected by the
JSC.

                                      -14-

<PAGE>

         "Professionals" shall mean physicians and other health care
practitioners who are permitted under the Laws of the Co-Commercialization
Country in which they work to prescribe the IL-1 Product.

         "Promotional Materials" shall mean, with respect to each IL-1 Product,
promotional, advertising, communication and educational materials relating to
such IL-1 Product for use in connection with the marketing, promotion and sale
of such IL-1 Product in the applicable Territory, and the content thereof, and
shall include, without limitation, logos, slogans, trade dress, website content
and artwork, promotional literature, product support materials and promotional
giveaways.

         "Publishing Party" shall the meaning set forth in Section 16.3.

         "Qualified Sales Representative" shall mean an individual employed by a
Party or its Affiliates (or who is part of a Contract Sales Force)
[******************************].

         "Regeneron" shall have the meaning set forth in the introductory
paragraph.

         "Regeneron Intellectual Property" shall mean the Regeneron Patent
Rights and any Know-How of Regeneron or any of its Affiliates.

         "Regeneron Patent Rights" shall mean those Patent Rights which are
owned by or licensed (with the right of sublicense) to Regeneron or any of its
Affiliates (other than pursuant to this Agreement or any Ancillary Agreement)
and which include at least one claim which would be infringed by the
manufacture, use, sale, offer for sale or import of an IL-1 Product at any time
during the applicable Term for such IL-1 Product, and for the avoidance of
doubt, Regeneron Patent Rights include any Patent Rights arising from the Phase
IIA or IIB Clinical Trials described in Section 2.4(c).

         "Regeneron Sole Inventions" shall have the meaning set forth in Section
12.1(a).

         "Region" shall mean each of NAFTA, Europe and the Rest of World.

         "Registration Filing" shall mean, with respect to each IL-1 Product,
the submission to the relevant Regulatory Authority of an appropriate
application seeking any Approval, and shall include, without limitation, any
marketing authorization application, supplementary application or variation
thereof, BLA, or any equivalent applications in any Co-Commercialization
Country.

         "Regulatory Authority" shall mean any federal, national, multinational,
state, provincial or local regulatory agency, department, bureau or other
governmental entity with authority over the marketing, pricing and/or sale of
any IL-1 Product in a country in the Territory, including, without limitation,
FDA in the United States and EMEA in Europe.

         "Regulatory Expenses" shall mean, with respect to an IL-1 Product, all
Out-of-Pocket Costs and Fully Allocated Costs incurred by or on behalf of a
Party in connection with the preparation and filing of Registration Filings and
the maintenance of Approvals.

         "Rest of World" shall mean, with respect to Trap-1 and Trap-2, all
countries in the applicable Territory except for NAFTA and Europe.

         "Rules" shall have the meaning set forth in Section 10.2(a).

                                      -15-

<PAGE>

         "Sales Infrastructure Elements" shall mean each of the following: (a) a
sales force automation system through which Qualified Sales Representatives can
record calls electronically, receive email communications and reports, view
sales reports and download physician targets and lists; (b) a sample
accountability system that meets the requirements of Section 6.14 and that
complies with all applicable Laws; (c) a sales training department that is
responsible for providing general sales training and product training to
Qualified Sales Representatives; (d) a department responsible for the design and
administration of the applicable Party's sales incentive plan; (e) a voice mail
system; (f) a system for sales reporting and analysis; (g) a sales
administration and operations department that handles, among other things, fleet
management; (h) a department that establishes and maintains territory alignments
consistent with target professionals lists; (i) an electronic roster system that
tracks sales force vacancy, turnover, demographics and territory occupancy; and
(j) an electronic field expense reporting system.

         "Secondary Product Presentation" shall mean a full product presentation
during a call in which one or more key messages related to an IL-1 Product are
presented in the second position and in a balanced manner consistent with the
terms of this Agreement, and [**********************************************].

         "Severed Clause" shall have the meaning set forth in Section 20.7.

         "Shared Promotion Expenses" shall mean, with respect to each IL-1
Product, Out-of-Pocket Costs and other costs (in the case of personnel costs for
personnel directly involved in the marketing or promotional activities,
determined based on the FTE Rate or such other basis as may otherwise be agreed
by the Parties) which are incurred by a Party or any of its Affiliates to the
extent consistent with the Consolidated Co-Commercialization Budget included in
the then applicable Consolidated Co-Commercialization Plan and related to the
Co-Commercialization of such IL-1 Product, including, without limitation, costs
in the following categories:

                  (a)      costs incurred in promoting and marketing such IL-1
         Product, including without limitation, advertising (including agency
         fees), market research, patient-oriented promotions, meetings,
         pre-Launch activities and expenses relating to launch of the IL-1
         Product, and managed markets/health authority liaisons (but excluding
         Detailing expenses);

                  (b)      amounts repaid or credited for bad debts;

                  (c)      costs associated with post-marketing drug safety
         surveillance;

                  (d)      medical affairs costs, and costs associated with
         medical/scientific liaisons (including regional scientific directors),
         medical education and publications, professional symposia, advisory
         boards, speaker and activity programs;

                  (e)      costs of Phase IV Clinical Trials in the
         Co-Commercialization Countries (excluding costs associated with any
         Phase IV Clinical Trials intended to support or maintain a Registration
         Filing for such IL-1 Product, including by way of example to support
         expanded labeling for such IL-1 Product, or to satisfy requirements
         imposed by Regulatory Authorities in connection with Approvals for such
         IL-1 Product, all of which are included in Development Costs) and
         pharmacoeconomic studies;

                                      -16-

<PAGE>

                  (f)      the cost of samples;

                  (g)      costs of materials and programs for the training of
         sales force, regional sales management and marketing management;

                  (h)      costs of Promotional Materials, telemarketing,
         e-marketing, field and headquarters' grants, exhibits, direct mail and
         sample alternative programs;

                  (i)      costs associated with global sales force training
         agreed by the JOC; provided, however, that each Party will train its
         own sales force (and that of its Affiliates) at its own expense;

                  (j)      amounts paid by way of milestones or royalties due
         under any Existing License or New License with respect to sales of such
         IL-1 Product,

                  (k)      amounts paid to a Third Party in a
         Co-Commercialization Country as a result of either Party, with the
         approval of the Intellectual Property Sub Committee, executing an
         agreement, including but not limited to a license agreement, with a
         Third Party in order to obtain freedom to operate with respect to such
         IL-1 Product in such Co-Commercialization Country; and

                  (l)      amounts paid, whether in damages or by a settlement
         approved by the IPSC, to a Third Party in a Co-Commercialization
         Country as a result of any allegation of infringement by any Party of a
         Third Party patent by the manufacture, Development or Commercialization
         of such IL-1 Product.

The foregoing shall not include any Out-of-Pocket Costs or other costs which (i)
are incurred prior to the Effective Date, (ii) are incurred in connection with
the manufacture of any IL-1 Product, or (iii) have been included in Development
Costs or Regulatory Expenses.

         "Shortfall Party" shall have the meaning set forth in Section 6.10(d).

         "Sole Inventions" shall have the meaning set forth in Section 12.1(a).

         "Stock Out Event" shall have the meaning set forth in Section 8.2(d).

         "Stock Purchase Agreement" shall mean the Stock Purchase Agreement
between the Parties dated as of the date hereof, together with the Registration
Rights Agreement contemplated thereby.

         "Strategic Plan" shall mean the [************] strategic plan,
developed by the JOC and approved by the JSC, setting forth the Parties'
strategies for optimizing the commercial value of the IL-1 Products.

         "Target Profit Split" shall mean, with respect to each IL-1 Product,
the applicable target profit splits set forth on SCHEDULE 1.

         "Technology Transfer Agreement" shall mean the agreement described in
Section 4.4(b).

         "Term" shall have the meaning set forth in Section 19.1.

                                      -17-

<PAGE>

         "Terminated Product" shall have the meanings set forth in Sections
19.2, 19.4 and 19.8, as applicable.

         "Territory" shall mean: (a) with respect to Trap-1 Products, the Trap-1
Territory; (b) with respect to IL-1 Antibody Products, the IL-1 Antibody
Territory; and (c) with respect to Trap-2 Products, the Trap-2 Territory.

         "Tertiary Product Presentation" shall mean a presentation during a call
consisting of [******************************************]. A Tertiary Product
Presentation shall not be counted as a PDE.

         "Third Party" shall mean any Person other than Novartis or Regeneron or
any Affiliate of either Party.

         "Trap-1" shall mean [*******************************************].

         "Trap-1 Product" shall mean one or more pharmaceutical products for
human and/or animal use which include Trap-1 as an active ingredient, alone or
in combination with one or more other active ingredients, for all indications.

         "Trap-1 Territory" shall mean all the countries of the world, excluding
Japan.

         "Trap-2" shall mean [*******************************************].

         "Trap-2 Opt-In Rights" shall mean the rights set forth in Section 5.4.

         "Trap-2 Product" shall mean one or more pharmaceutical products for
human and/or animal use which include Trap-2 as an active ingredient, alone or
in combination with one or more other active ingredients, for all indications.

         "Trap-2 Territory" shall mean all the countries of the world, excluding
Japan.

         "Trial Success Criteria" shall mean the indicia of success in a
Clinical Trial: (a) set forth in the Preliminary Development Plan (as may be
amended from time to time in accordance with this Agreement) with respect to the
Phase IIB Clinical Trial for rheumatoid arthritis ongoing at the Effective Date
with respect to Trap-1, and (b) with respect to any other Clinical Trial, as
agreed by the Parties through the JSC prior to the commencement of such Clinical
Trial.

         "United States" or "U.S." shall mean the United States of America,
including its territories and possessions and its military bases and
commissaries wherever located in the applicable Territories, the District of
Columbia and Puerto Rico.

                                      -18-

<PAGE>

                                    ARTICLE II

                                   COOPERATION

                  2.1 Scope of Cooperation. The Parties agree to cooperate in
good faith under this Agreement and any Ancillary Agreements to effectively and
efficiently Develop and Commercialize IL-1 Products in the Co-Commercialization
Countries in such a manner as to optimize the commercial potential of IL-1
Products. To achieve these goals, the Parties wish to provide for: (a) the joint
worldwide (excluding Japan) Development of IL-1 Products; (b) the Co-Promotion
of IL-1 Products in the Co-Promotion Countries; (c) the Co-Branding of IL-1
Products in the Co-Branding Countries; (d) the Co-Marketing of IL-1 Products in
the Co-Marketing Countries; and (e) the manufacture of IL-1 Products within the
Territory by Novartis (for greater clarity, Novartis will or will have
manufactured the IL-1 Products, however, Regeneron will manufacture the Clinical
Supply Requirements for the Trap-1 Product through the earlier of the date of
first Launch of a Trap-1 Product or the date that Novartis is capable of
producing such Clinical Supply Requirements following the technology transfer
referred to in Section 8.2(a)). For purposes thereof, the Parties shall
establish various Committees as set forth in Article III of this Agreement to
oversee the Development and Commercialization of IL-1 Products, and each Party
shall, subject to the terms and conditions set forth in Article XVI, provide (or
cause its Affiliates to provide) to any relevant Committee any necessary
confidential Company Information and such other information as may be reasonably
required for the Parties to operate effectively and efficiently under this
Agreement and any applicable Ancillary Agreement.

                  2.2 Compliance With Law. Both Novartis and Regeneron, and
their respective Affiliates, shall perform their obligations under this
Agreement, any applicable Ancillary Agreement and any then-applicable Plans
(including, without limitation, the deployment of their respective sales forces)
in an effort to Develop, manufacture, market and Detail IL-1 Products
effectively in the Co-Commercialization Countries and in accordance with
applicable Law. No Party or any of its Affiliates shall, or shall be required
to, undertake any activity under or in connection with this Agreement which
violates, or which it believes, in good faith, may violate, any applicable Law.

                  2.3 Diligence. Subject to the terms of this Agreement, each
Party (and its Affiliates) shall diligently work to fulfill all responsibilities
assigned to it under this Agreement, any applicable Ancillary Agreement and any
then-applicable Plans.

                  2.4 Reservation of Rights.

                  (a)      IL-1 Antibody. With respect to the IL-1 Antibody, all
rights not specifically granted herein to Regeneron are expressly reserved to
Novartis. For the avoidance of doubt, Novartis reserves all right, title and
ownership to [*********************]. Nothing in this Agreement shall be
interpreted as granting to Regeneron any rights with respect to
[****************************************].

                  (b)      Trap-1 and Trap-2. With respect to each of Trap-1 and
Trap-2, all rights not specifically granted herein to Novartis are expressly
reserved to Regeneron.

                  (c)      Limitation on Exercise of Rights Outside of
Collaboration. Notwithstanding the foregoing, Novartis and Regeneron agree that,
with effect from: (a) the Effective Date, with respect to Trap-1; (b) the proper
exercise by Regeneron of the IL-1 Antibody Opt-In Rights, with respect to the
IL-1

                                      -19-

<PAGE>

Antibody; and (c) the proper exercise by Novartis of the Trap-2 Opt-In Rights,
with respect to Trap-2, and in each case, for so long as this Agreement remains
in effect with respect to such IL-1 Product, neither it nor any of its
Affiliates, either alone or through any Third Party, shall, for the term of the
Agreement with respect to such IL-1 Product, Develop or Commercialize the
applicable IL-1 Product in the applicable Territory, except pursuant to this
Agreement; provided, however, that Regeneron may, at its option and at its sole
expense, conduct additional (i.e., not contemplated by the Preliminary
Development Plan) Phase IIA and Phase IIB Clinical Trials with respect to Trap-1
or Trap-2. In the event that Regeneron conducts any such additional Phase IIA or
Phase IIB Clinical Trials, all results, Know-How and Patent Rights generated in
or arising from any such Clinical Trial shall be subject to the grants of rights
by Regeneron to Novartis pursuant to this Agreement, and except as expressly set
forth in the foregoing proviso, for so long as this Agreement remains in effect
with respect to such IL-1 Product, the Trap-1 Product may only be Developed and
Commercialized pursuant to the Agreement. For the avoidance of doubt, no
additional consideration shall be payable by Novartis with respect to the
conduct of any such Clinical Trial, or the rights granted herein with respect to
any results, Know-How or Patent Rights generated in or arising from any such
Clinical Trial.

                  2.5 Further Assurances and Transaction Approvals. Upon the
terms and subject to the conditions hereof, each of the Parties will use all
Commercially Reasonable Efforts to (i) after the Effective Date, take, or cause
to be taken, all actions necessary, proper or advisable under applicable Laws or
otherwise to consummate and make effective the transactions contemplated by this
Agreement, and (ii) obtain from the requisite Governmental Authorities any
consents, licenses, permits, waivers, approvals, authorizations or orders
required to be obtained or made in connection with the authorization, execution
and delivery of this Agreement and the consummation of the transactions
contemplated by this Agreement and (iii) make all necessary filings, and
thereafter make any other advisable submissions, with respect to this Agreement
and the transactions contemplated by this Agreement required under applicable
Laws. The Parties will cooperate with each other in connection with the making
of all such filings, including by providing copies of all such non-confidential
documents to the other Party and its advisors prior to the filing and, if
requested, by accepting all reasonable additions, deletions or changes suggested
in connection therewith. Each Party will furnish all information required for
any applicable or other filing to be made pursuant to the rules and regulations
of any applicable Laws in connection with the transactions contemplated by this
Agreement. For the avoidance of doubt, nothing in this Section 2.5, shall oblige
either Party or its Affiliates to seek or obtain Approval for any IL-1 Product
in any jurisdiction.

                                  ARTICLE III

                                   MANAGEMENT

                  3.1 Committees/Management.

                  (a)      The Parties agree to establish, for the purposes
specified herein and/or in any applicable Ancillary Agreement, a Joint Steering
Committee, a Joint Operating Committee and, as sub-committees of the Joint
Operating Committee, a U.S. Joint Commercialization Committee, a Finance
Sub-Committee and an Intellectual Property Sub-Committee ("IPSC"). The Parties
may also agree, through the Joint Operating Committee, to

                                      -20-

<PAGE>

establish, as sub-committees of the Joint Operating Committee, a Joint
Development Sub-Committee, a Joint Regulatory Sub-Committee, a Joint
Commercialization Sub-Committee, and, for each other Co-Commercialization
Country, a Country Joint Commercialization Sub-Committee. Each Party shall bear
its own costs associated with its participation in the Committees, and such
costs shall not be included in the Development Costs or Shared Promotion
Expenses.

                  (b)      Each of the Committees and the Executive Officers
shall exercise their decision-making authority hereunder in good faith and in a
commercially reasonably manner for the purpose of optimizing the commercial
potential of and financial returns from the IL-1 Products without regard to any
other pharmaceutical product including, without limitation, any Trap-1 Product,
IL-1 Antibody Product, or Trap-2 Product which has not been elected or for which
this Agreement has been terminated with respect to such product in Development
or being Commercialized or sold by or through a Party (the "Collaboration
Purpose"). The Parties acknowledge and agree that none of the Committees or the
Executive Officers shall have the power to amend any of the terms or conditions
of this Agreement or any of the Ancillary Agreements, other than by mutual
agreement of the Parties as set forth in Section 20.5.

                  (c)      [*********************************************]. No
such disputes (other than disputes resolved in a manner inconsistent with this
Agreement or any Ancillary Agreement and Legal Disputes) shall be subject to any
dispute resolution mechanism or procedure other than pursuant to this Article
III.

                  3.2 The Joint Steering Committee.

                  (a)      Composition. The Joint Steering Committee (the "JSC")
shall be established by the Parties to supervise the performance of the Parties
hereunder and shall be comprised of six (6) members consisting of senior
leadership executives of Novartis and Regeneron who, in the case of Novartis,
are responsible for global marketing and clinical development and, in the case
of Regeneron, including those who have responsibility for marketing and clinical
development. Promptly, but in no event more than thirty (30) days after the
Effective Date, Novartis shall appoint three (3) representatives and Regeneron
shall appoint three (3) representatives to the JSC. A Party may change any of
its representatives at any time if a new person is appointed to any of the
foregoing positions by giving written notice to the other Party. A JSC member
may not, concurrently with JSC membership, be a member of any other Committee.

                  (b)      Chairperson of the JSC. Novartis will designate the
initial chairperson of the JSC, and the right to designate the JSC chairperson
shall rotate between Novartis and Regeneron at the end of each calendar year.
The chairperson of the JSC shall be: (i) entitled to set meeting agendas;
provided that the agenda shall include any matter reasonably requested by either
Party; (ii) required to call emergency meetings of the JSC at the request of a
Party; and (iii) required, at the request of either Party, to present JSC
disputes that have been unresolved for thirty (30) days to the Executive Officer
of Novartis and the Executive Officer of Regeneron, pursuant to Section 3.7. The
JSC chairperson shall be responsible for recording, preparing and, within a
reasonable time, issuing minutes of the JSC meetings, which meeting minutes
shall be submitted for approval of the members of the JSC.

                  (c)      Meetings of the JSC. The JSC shall meet whenever any
member of the JSC shall make such a request in writing to the chairperson
(including a request by a Party for

                                      -21-

<PAGE>

an emergency meeting as contemplated by Section 3.2(b) above) or whenever a
matter is referred to the JSC by the JOC pursuant to Section 3.7; provided,
however, that the JSC shall in no event meet less frequently than once per year.
Decisions of the JSC shall be made unanimously, each Party having one (1) vote
regardless of the number of representatives present or voting; provided that no
such vote shall be valid unless each Party is represented by at least one member
either by proxy or actual presence at the meeting at which the vote is taken.
Subject to appropriate confidentiality undertakings where applicable, additional
participants may be invited by any member of the JSC to attend meetings where
appropriate (e.g., the Alliance Managers, representatives of regulatory affairs
or outside consultants). Such additional participants shall not be deemed a
member of the JSC, nor shall they have any rights or responsibilities of a
member of the JSC.

                  (d)      Authority of the JSC. Subject to Section 3.7, the JSC
shall have the final decision-making authority with respect to all matters
within the jurisdiction of any of the Committees established pursuant to this
Agreement or any of the Ancillary Agreements which are referred to the JSC for
determination or resolution. The JSC shall exercise this authority in good faith
and in accordance with this Agreement, all decisions shall have a reasonable
basis and any such decision shall be binding upon the Parties, without
limitation, however, to the Parties' rights and remedies with respect to any
Legal Dispute.

                  3.3 Responsibilities of the JSC. The responsibilities of the
JSC shall be exercised consistent with this Agreement and shall include, but
shall not be limited to, the following:

                  (a)      coordinating Strategic Plans for optimizing the
Development and the commercial value of IL-1 Products in the
Co-Commercialization Countries;

                  (b)      approve target profiles for particular IL-1 Products;

                  (c)      reviewing and approving on a timely annual basis
Strategic Plans, Consolidated Co-Commercialization Plans (including related
Consolidated Co-Commercialization Budgets) and Consolidated Co-Development Plans
(including related Consolidated Co-Development Budgets) prepared by the JOC;

                  (d)      approving Product Trademarks for each of the IL-1
Products;

                  (e)      reviewing the efforts of the Parties in performing
their respective Co-Development and Co-Promotion and Co-Branding activities, as
applicable, in the Co-Commercialization Countries;

                  (f)      considering and acting upon such other matters as are
specified in this Agreement; and

                  (g)      attempting in good faith to resolve any disputes
referred to it by the Joint Operating Committee.

                  3.4 Joint Operating Committee.

                  (a)      Composition. The Joint Operating Committee ("JOC")
shall be established by the Parties to, among other things, prepare and, to the
extent provided herein, submit to the JSC for approval consolidated Development,
regulatory, promotion and

                                      -22-

<PAGE>

marketing plans for the IL-1 Product in the Co-Commercialization Countries. The
JOC shall be comprised of eight (8) members consisting of the senior executives
of Novartis and Regeneron who, in the case of Novartis, are responsible for
global marketing and clinical development and, in the case of Regeneron,
including those who have responsibility for marketing and clinical development.
Promptly after the Effective Date, Novartis and Regeneron will each appoint four
(4) appropriate representatives to the JOC; provided that each Party must
appoint, as one of its representatives on the JOC, its Alliance Manager. A Party
may change any of its representatives at any time by giving written notice to
the other Party but the replacement representative must also be a senior
executive from Novartis or Regeneron (with appropriate expertise to replace the
outgoing member). The total number of JOC members may be changed by unanimous
vote of the JOC from time to time as appropriate; provided that the JOC shall in
all cases be comprised of an equal number of members from each of Novartis and
Regeneron.

                  (b)      Chairperson of the JOC. Regeneron will designate the
initial chairperson of the JOC, and the right to designate the JOC chairperson
shall rotate between Novartis and Regeneron at the end of each calendar year.
The JOC chairperson shall be: (i) entitled to set meeting agendas; provided that
the agenda shall include any matter reasonably requested by either Party; (ii)
required to call emergency meetings of the JOC at the request of a JOC member;
and (iii) required, at the request of either Party, to present JOC disputes
(together with a JOC member of the other Party) that have been unresolved for
thirty (30) days to the JSC pursuant to Section 3.7. The JOC chairperson shall
be responsible for recording, preparing and, within a reasonable time, issuing
minutes of the JOC meetings, which meeting minutes shall be submitted for
approval of the members of the JOC.

                  (c)      Meetings of the JOC. The chairperson of the JOC shall
call meetings when deemed by the chairperson to be appropriate or when requested
by a Party; provided, however, that such meetings shall be held on at least a
quarterly basis for the first year following the Effective Date, and thereafter
no less frequently than twice per year. If possible, the meetings shall be held
in person (to the extent practicable, alternating the site for such meetings
between the companies) or where appropriate, by video or telephone conference.
The Parties shall determine the form of the meeting. Decisions of the JOC shall
be made unanimously, each Party having one (1) vote regardless of the number of
representatives present or voting; provided that no such vote shall be valid
unless each Party is represented by at least one member either by proxy or
actual presence at the meeting at which the vote is taken. Voting by proxy shall
be permissible. Subject to appropriate confidentiality undertakings where
applicable, additional participants may be invited by any member to attend
meetings where appropriate (e.g., representatives of regulatory affairs or
outside consultants). Such additional participants shall not be deemed to be a
member of the JOC, or to have any rights or responsibilities of a member of the
JOC.

                  3.5 JOC Responsibilities. The responsibilities of the JOC
shall also include, but shall not be limited to:

                  (a)      making recommendations to the JSC with respect to
target profiles for IL-1 Products (including key labeling claims required for
commercial success of IL-1 Products given the competitive environment and any
other key IL-1 Product features and benefits that would be used to develop or
support a promotional message for IL-1 Products);

                                      -23-

<PAGE>

                  (b)      preparing, or overseeing the preparation of,
Strategic Plans for IL-1 Products for the Co-Commercialization Countries for
final approval by the JSC, and updating each such Plan not less frequently than
once per Contract Year;

                  (c)      preparing, or overseeing the preparation of,
Consolidated Co-Commercialization Plans (and related Consolidated
Co-Commercialization Budgets) for the Co-Commercialization Countries in
accordance with applicable Strategic Plans for final approval by the JSC, and
updating each such Plan not less frequently than once per Contract Year;

                  (d)      preparing, or overseeing the preparation of,
Consolidated Co-Development Plans (and related Consolidated Co-Development
Budgets) for the Co-Commercialization Countries in accordance with applicable
Strategic Plans for final approval by the JSC, and updating each such Plan not
less frequently than once per Contract Year;

                  (e)      monitoring compliance with the Consolidated
Co-Commercialization Plans and the Consolidated Co-Development Plans and, in
connection therewith, reviewing and approving any material change in a
Consolidated Co-Commercialization Plan or Consolidated Co-Development Plan,
including, without limitation, specifically approving any change(s) in any line
item or category of expenses in any Consolidated Co-Commercialization Budget or
Consolidated Co-Development Budget which individually, or together with such
previously approved changes in such line item or category, would result in a
greater than five percent (5%) increase or decrease in the amount budgeted in
such line item or category under either such Consolidated Co-Commercialization
Budget or Consolidated Co-Development Budget, it being understood and agreed
that expenditures by the Parties with respect to any matter included in a
Consolidated Co-Commercialization Budget or Consolidated Co-Development Budget
which individually or together with such prior expenditures, exceed by less than
5% the amount budgeted in any line item or category of expenses in such
Consolidated Co-Commercialization Budget or Consolidated Co-Development Budget
with respect to such matter shall not require approval by the JOC and for all
purposes of this Agreement shall be deemed an expenditure in accordance with
such Consolidated Co-Commercialization Budget or Consolidated Co-Development
Budget, as applicable.

                  (f)      approving protocols for Clinical Trials of IL-1
Products in the applicable Territory, and monitoring and making modifications to
such Clinical Trials;

                  (g)      reviewing and approving material regulatory
correspondence, final study reports and submissions to Regulatory Authorities
with respect to IL-1 Products;

                  (h)      facilitating an exchange between the Parties of data,
information, material and results relating to the Development of IL-1 Products
in the applicable Territory;

                  (i)      establishing and implementing procedures regarding
the collection, sharing and reporting of adverse event information related to
IL-1 Products in each country in the applicable Territory;

                  (j)      preparing and maintaining the overall plan for
Commercialization of IL-1 Products in the Co-Commercialization Countries,
defining joint planning and executing items, including, without limitation,
timelines, IL-1 Product branding, positioning, core

                                      -24-

<PAGE>

messages, tactical plans, staffing, Detailing, Alternate Marketing Channels,
budgets and amendments thereto;

                  (k)      defining target groups to be covered by overall
marketing efforts in the Co-Commercialization Countries, including, without
limitation, key opinion leaders, physician groups, hospitals and regional buying
groups, managed care organizations and governmental and government-affiliate
buyers;

                  (l)      reviewing the Parties' respective marketing and
promotional activities for consistency with the Consolidated
Co-Commercialization Plan;

                  (m)      considering and selecting Product Trademarks for IL-1
Products for approval by the JSC;

                  (n)      establishing the contents, design and layout of
packaging for each IL-1 Product, on a country-by-country basis where applicable;

                  (o)      developing and implementing plans and policies
regarding journal and other publications with respect to IL-1 Products;

                  (p)      developing concepts for potential Phase IIIB and
Phase IV Clinical Trials for IL-1 Products;

                  (q)      establishing as sub-committees of the JOC
(collectively, the "Joint Sub-Committees"), a U.S. Joint Commercialization
Sub-Committee, a Finance Sub-Committee and an Intellectual Property
Sub-Committee, each of which: (i) shall be composed of an equal number of
representatives of each Party, with the right to appoint the chairperson
rotating between the Parties, and otherwise organized in such a manner as the
JOC deems appropriate; (ii) shall be delegated such responsibilities as the JOC
deems appropriate; and (iii) shall report to the JOC;

                  (r)      establishing, as and when necessary and/or
appropriate, additional Joint Sub-Committees of the JOC such as a Joint
Development Sub-Committee, a Joint Regulatory Sub-Committee, a Joint
Commercialization Sub-Committee and/or Joint Country Commercialization
Sub-Committees, which additional Joint Sub-Committees: (i) shall be composed of
an equal number of representatives of each Party, with the right to appoint the
chairperson rotating between the Parties, and otherwise organized in such a
manner as the JOC deems appropriate; (ii) shall be delegated such
responsibilities as the JOC deems appropriate; and (iii) shall report to the
JOC; and

                  (s)      considering and acting upon such other matters as are
specified in this Agreement or by the Joint Steering Committee.

                                      -25-

<PAGE>

                  3.6 Alliance Management Representative. Each of Novartis and
Regeneron shall appoint a senior representative who possesses a general
understanding of clinical, regulatory, manufacturing and marketing issues to act
as its Alliance Manager ("Alliance Manager"). Each Alliance Manager shall be
charged with creating and maintaining a collaborative work environment within
and among the Committees. Each Alliance Manager will also be responsible for:

                  (a)      coordinating the various functional representatives
of Novartis or Regeneron, as appropriate, in developing and executing global
strategies and Plans for the IL-1 Product in an effort to ensure global
consistency and efficiency;

                  (b)      providing single-point communication for seeking
consensus both internally within the respective Party's organization and
together regarding key global strategy and Plan issues, as appropriate,
including facilitating review of external corporate communications; and

                  (c)      identifying and raising cross-country, cross-Party
and/or cross-functional disputes to the JSC in a timely manner.

                  3.7 Resolution of Governance Matters.

                  (a)      Generally. The Parties shall cause their respective
representatives on the Committees to use their Commercially Reasonable Efforts
to resolve all matters presented to them as expeditiously as possible, and

                  (i)      In the case of any matter which cannot be resolved by
         the applicable Joint Sub-Committee of the JOC, such matter shall, at
         the request of either Party, promptly, and in any event within fifteen
         (15) days after such request, be referred by the chairperson of such
         Sub-Committee to the JOC for resolution;

                  (ii)     in the case of any matter which cannot be resolved by
         the JOC, such matter shall, at the request of either Party, promptly,
         and in any event within thirty (30) days after such request, be
         referred by the chairperson of the JOC to the JSC for resolution; and

                  (iii)    in the event any matter which cannot be resolved by
         the JSC, such matter shall, at the request of either Party, be resolved
         in accordance with the dispute resolution procedures set forth in
         Section 3.7(b) and (c) below.

                  (b)      Executive Officers' Resolution of Disputes. In the
event that the JSC is, after a period of thirty (30) days from the date a matter
is submitted to it for decision in accordance with this Section 3.7, unable to
make a decision due to a lack of required unanimity, either Party may, by notice
to the chairperson of the JSC, require that the matter be submitted to the
Executive Officers for a joint decision. In such event, the chairperson of the
JSC, by written notice to each Party delivered within five (5) days after
receipt of the notice from a Party pursuant to the immediately preceding
sentence, shall formally request that the dispute be resolved by the Executive
Officers, specifying the nature of the dispute with sufficient specificity to
permit adequate consideration by such Executive Officers. The Executive Officers
shall diligently and in good faith, attempt to resolve the referred dispute
within thirty (30) days of receiving such written notification, failing which,
except as set forth in Section 3.7(c) below and except for Legal Disputes,
[***************************].

                                      -26-

<PAGE>

Any such final decision [********************] shall be made, and communicated
in writing [***********************]. For the avoidance of doubt, such disputes
referred to the Executive Officers for resolution (other than Legal Disputes)
shall not be subject to any dispute resolution mechanism or procedure other than
pursuant to this Article III.

                  (c)      Mutual Agreement Requirements. Notwithstanding the
provisions of Section 3.7(b) above,[***************************************]:

                  (i)      [***************************************];

                  (ii)     [**************************************];

                  (iii)    [**************************************];

                  (iv)     [**************************************]; and

                  (v)      [**************************************].

                  (d)      Performance. Pending resolution of any matter
pursuant to this Section 3.7, the Parties covenant to continue their performance
under the Agreement in accordance with the terms thereof. To facilitate such
continued performance, pending resolution by the Executive Officers of any
referred dispute with respect to an annual Consolidated Co-Commercialization
Budget or annual Consolidated Co-Development Budget, the Executive Officers
shall negotiate in good faith in an effort to agree to appropriate interim
budgets to allow the continued Co-Development and Co-Commercialization of the
IL-1 Product pursuant to this Agreement.

                  (e)      Obligations of the Parties and their Affiliates. The
Parties shall cause their respective designees on the Committees and their
respective Executive Officers to take the actions and make the decisions
provided herein to be taken and made by such respective designees and Executives
in the manner and within the applicable time periods provided herein. To the
extent a Party performs any of its obligations hereunder through any Affiliate
of such Party, such Party shall be fully responsible and liable hereunder for
any failure of such performance, and each Party agrees that it will cause each
of its controlled Affiliates to comply with any provision of this Agreement
which restricts or prohibits a Party from taking any specified action.

                                   ARTICLE IV

               EXISTING PATENT AND KNOW-HOW RIGHTS; LICENSE GRANTS

                  4.1 Regeneron License Grants Regarding Trap-1. Subject to the
terms and conditions of this Agreement and any license within the Regeneron
Patent Rights, Regeneron hereby grants to Novartis and its Affiliates the right
and license under the Regeneron Intellectual Property to manufacture, and to
Co-Develop, Co-Commercialize and Co-Market the Trap-1 Product throughout the
Trap-1 Territory for the Term of this Agreement. Such license shall be
co-exclusive with Regeneron and its Affiliates only. The rights granted to
Novartis and its Affiliates under the Regeneron Intellectual Property to sell or
offer to sell the Trap-1 Product shall be sublicensable to Distributors of
Novartis (but not with respect to distribution, marketing, sale or offer for
sale of the Trap-1 Product in any country listed on SCHEDULE 10), and otherwise
only with the prior written consent of Regeneron, which

                                      -27-

<PAGE>

consent shall not be unreasonably withheld or delayed. For the avoidance of
doubt, Regeneron may withhold such consent if it reasonably determines such
sublicense would reduce Regeneron's financial return from the sale of the Trap-1
Product in the applicable country.

                  4.2 Novartis License Grants Regarding the IL-1 Antibody.
Subject to the terms and conditions of this Agreement and any license within the
Novartis Patent Rights, Novartis and its Affiliates hereby grant to Regeneron
and its Affiliates the right and license under the Novartis Intellectual
Property to Co-Develop, Co-Commercialize and Co-Market the IL-1 Antibody Product
throughout the IL-1 Antibody Territory for the Term of this Agreement with
respect to the IL-1 Antibody Product. Such license shall be conditional upon the
proper exercise by Regeneron of the IL-1 Antibody Opt-In Right and shall be
co-exclusive with Novartis and its Affiliates only. The rights granted to
Regeneron and its Affiliates hereunder shall not be sublicensable.

                  4.3 Regeneron License Grants Regarding Trap-2. Subject to the
terms and conditions of this Agreement and any license within the Regeneron
Patent Rights, Regeneron hereby grants to Novartis and its Affiliates the right
and license under the Regeneron Intellectual Property to manufacture, and to
Co-Develop, Co-Commercialize and Co-Market the Trap-2 Product throughout the
Trap-2 Territory for the Term of this Agreement with respect to the Trap-2
Product. Such license shall be conditional upon the proper exercise by Novartis
of the Trap-2 Opt-In Right and shall be co-exclusive with Regeneron and its
Affiliates only. The rights granted to Novartis and its Affiliates under the
Regeneron Intellectual Property to sell or offer to sell the Trap-2 Product
shall be sublicensable to Distributors of Novartis (but not with respect to
distribution, marketing, sale or offer for sale of the Trap-2 Product in any
country listed on SCHEDULE 10), and otherwise only with the prior written
consent of Regeneron, which consent shall not be unreasonably withheld or
delayed. For the avoidance of doubt, Regeneron may withhold such consent if it
reasonably determines such sublicense would reduce Regeneron's financial return
from the sale of the Trap-2 Product in the applicable country.

                  4.4 Technology Transfer.

                  (a)      To the extent reasonably necessary for each Party to
exercise its rights and perform its obligations under this Agreement with
respect to the other Party's intellectual property, and from time to time during
the applicable Term, each Party shall provide to the other Party one (1) copy of
each physical embodiment of such Party's applicable intellectual property as set
forth in the Technology Transfer Agreement. Without limiting the generality of
any other provision of this Agreement or the Technology Transfer Agreement, each
Party shall make its scientific and technical personnel available to the other
Party to answer any questions or provide instruction as reasonably necessary
with respect to such Party's intellectual property licensed to the other Party
hereunder.

                  (b)      In accordance with the terms of a Technology Transfer
Agreement (to be negotiated in good faith as soon as practicable, but in any
event within sixty (60) days of the Effective Date), Regeneron will transfer and
license to Novartis such Know-How and Regeneron Intellectual Property on terms
to be set forth in the Technology Transfer Agreement to allow Novartis to assume
the manufacturing of the Trap-1 Product. The Parties agree to enter into a
similar technology transfer agreement, as needed, for the Trap-2 Product.

                                      -28-

<PAGE>

                  4.5 Sublicenses. Novartis shall remain responsible for the
compliance by its Distributors and permitted sublicensees with applicable terms
and obligations set forth herein. Novartis agrees that any sublicense granted
pursuant to Section 4.1 or 4.3 shall be consistent with, and expressly subject
to, the covenants, terms and conditions set forth in this Agreement. Without
limitation of the generality of the foregoing, any sublicense granted pursuant
to Section 4.1 or 4.3 shall contain all of the terms required by the Amgen
License Agreement to be included in a sublicense of any rights licensed to
Regeneron thereunder, including, without limitation, that Amgen Inc. shall be a
direct third party beneficiary of any such sublicense. Promptly after entering
into any such sublicense, or any amendment or modification thereto, Novartis
will provide a true and correct copy thereof to Regeneron.

                                   ARTICLE V

                          DEVELOPMENT AND OPT-IN RIGHTS

                  5.1 Pre-Phase III Development of the IL-1 Antibody.

                  (a)      Novartis and its Affiliates shall be solely
responsible, in Novartis's discretion, for the Development of the IL-1 Antibody
Product through the End of Phase II Development and for all associated
Development costs and expenses. Without limiting the foregoing, Novartis and its
Affiliates shall have the right, exercisable in their sole discretion, to
determine [*****************************************] and nothing in this
Agreement shall be interpreted as granting to Regeneron any rights with respect
to [*********************************].

                  (b)      Novartis shall keep Regeneron and the JSC informed of
Novartis' Development activities with respect to the IL-1 Antibody Product
through the End of Phase II Development of the IL-1 Antibody Product by
submitting to the JSC, annually on each anniversary of the Effective Date, a
development plan with respect to the future Development of the IL-1 Antibody
Product and a progress report summarizing all Development activities undertaken
with respect to the IL-1 Antibody Product in the preceding year and which shall
include all relevant data from such Development activities. Each such
development plan and progress report shall be in such form and in such level of
detail as may be reasonably requested by Regeneron.

                  (c)      Novartis shall also provide Regeneron and the JSC
with reasonable advance notice of any meetings between Novartis and any
Regulatory Authority relating to the Development of any IL-1 Antibody Product
prior to the End of Phase II Development. To the extent permitted under Law,
Novartis shall permit Regeneron to have representatives attend any such
regulatory meeting with respect to the Development of any IL-1 Antibody Product
prior to the End of Phase II Development.

                  5.2 Pre-Phase III Development of Trap-2.

                  (a)      Regeneron shall be solely responsible, in its sole
discretion, for the Development of the Trap-2 Product through the End of Phase
II Development and for all associated Development costs and expenses.

                  (b)      Regeneron shall keep Novartis and the JSC informed of
Regeneron's Development activities with respect to the Trap-2 Product through
the End of Phase II Development of the Trap-2 Product by submitting to the JSC,
annually on each anniversary

                                      -29-

<PAGE>

of the Effective Date, a development plan with respect to the future Development
of the Trap-2 Product and a progress report summarizing all Development
activities undertaken with respect to the Trap-2 Product in the preceding year
and which shall include all relevant data from such Development activities. Each
such development plan and progress report shall be in such form and in such
level of detail as may be reasonably requested by Novartis.

                  (c)      Regeneron shall also provide Novartis and the JSC
with reasonable advance notice of any meetings between Regeneron and any
Regulatory Authority relating to the Development of any Trap-2 Product prior to
the End of Phase II Development. To the extent permitted under Law, Regeneron
shall permit Novartis to have representatives attend any such regulatory meeting
with respect to Development of any Trap-2 Product prior to the End of Phase II
Development.

                  5.3 IL-1 Antibody Opt-In Rights.

                  (a)      Novartis hereby grants to Regeneron an exclusive
option to Co-Develop and Co-Commercialize with Novartis and its Affiliates the
IL-1 Antibody Product on the terms and conditions set forth in this Agreement.

                  (b)      Within forty-five (45) days after the End of Phase II
Development of the IL-1 Antibody Product, Novartis shall deliver to Regeneron
written notice of the End of Phase II Development, accompanied by a written
report setting forth such efficacy, safety, clinical and medical data as may be
material to the feasibility of further Developing and Commercializing the IL-1
Antibody Product, which shall include, without limitation, a proposed
development plan and budget and a summary of the data generated from the
pre-clinical and clinical studies in sufficient detail so as to reasonably
demonstrate that efficacy has been achieved in accordance with defined endpoints
and whether any unexpected or untoward effects resulted from such studies which
would limit further Development of the IL-1 Antibody Product. For a period of
thirty (30) days from and after the delivery of such notice and reports,
Regeneron shall have the right to request from Novartis such additional
information then in the possession of or readily available to Novartis as
Regeneron may reasonably require in order to make a scientific, legal and
business evaluation of the Development and marketing potential of the IL-1
Antibody Product. Novartis shall also promptly notify Regeneron of, and promptly
provide to Regeneron, all material new data relating to the IL-1 Antibody
Product that comes into Novartis' possession during such period, whether or not
such data is specifically requested by Regeneron.

                  (c)      For ninety (90) days after the date of delivery of
the notice and written report described in Section 5.3(b) above or, if later,
the date Regeneron has received the additional information requested by
Regeneron in accordance with Section 5.3(b), Regeneron shall have the right to
elect to Co-Develop and Co-Commercialize the IL-1 Antibody Product on the terms
and conditions set forth in this Agreement. Any exercise of the IL-1 Antibody
Opt-In Right shall be made by written notice to Novartis, accompanied by the
IL-1 Antibody Opt-In Payment and shall become effective at the end of the month
during which such notice was delivered to Novartis. Development Costs with
respect to the IL-1 Antibody Product incurred after the effective date of such
notice shall be shared by the Parties in accordance with Schedule 4. If
Regeneron fails to exercise its IL-1 Antibody Opt-In Right as set forth above,
the IL-1 Antibody shall not be included in the Co-Development, manufacture,
Co-Commercialization or Co-Marketing of IL-1 Products as contemplated by this
Agreement, this Agreement (including, without limitation, Sections 2.1, 2.4(c),
4.2, 4.4, 5.1, 5.3, 5.5, 6.1, 8.3, 13.3 and 15.2(b) and Articles III, VII and
XI) shall be of no force or effect with respect

                                      -30-

<PAGE>

to the IL-1 Antibody, and Novartis and its Affiliates shall be free to Develop
and Commercialize the IL-1 Antibody Product, alone or in collaboration with any
Third Party, without being subject to the provisions of this Agreement
(including, without limitation, Section 6.22).

                  5.4 Trap-2 Opt-In Right.

                  (a)      Regeneron hereby grants to Novartis an exclusive
option to Co-Develop and Co-Commercialize with Regeneron the Trap-2 Product on
the terms and conditions set forth in this Agreement.

                  (b)      Within forty-five (45) days after the End of Phase II
Development of the Trap-2 Product, Regeneron shall deliver to Novartis written
notice of the End of Phase II Development, accompanied by a written report
setting forth such efficacy, safety, clinical and medical data as may be
material to the feasibility of further Developing and Commercializing the Trap-2
Product, which shall include, without limitation, manufacturing data, a proposed
development plan and budget and a summary of the data generated from the
pre-clinical and clinical studies in sufficient detail so as to reasonably
demonstrate that efficacy has been achieved in accordance with defined endpoints
and whether any unexpected or untoward effects resulted from such studies which
would limit further Development of the Trap-2 Product. For a period of thirty
(30) days from and after the delivery of such notice and reports, Novartis shall
have the right to request from Regeneron such additional information then in the
possession of or readily available to Regeneron as Novartis may reasonably
require in order to make a scientific, legal and business evaluation of the
Development and marketing potential of the Trap-2 Product. Regeneron shall also
promptly notify Novartis of, and promptly provide to Novartis, all material new
data relating to the Trap-2 Product that comes into Regeneron's possession
during such period, whether or not such data is specifically requested by
Novartis.

                  (c)      For ninety (90) days after the date of delivery of
the notice and written report described in Section 5.4(b) above or, if later,
the date Novartis has received the additional information requested by Novartis
in accordance with Section 5.4(b), Novartis shall have the right to elect to
Co-Develop and Co-Commercialize the Trap-2 Product on the terms and conditions
set forth in this Agreement. Any exercise of the Trap-2 Opt-In Right shall be
made by written notice to Regeneron and shall become effective at the end of the
month during which such notice was delivered to Regeneron. Development Costs
with respect to the Trap-2 Product incurred after the effective date of such
notice shall be shared by the Parties in accordance with Schedule 4. If Novartis
fails to exercise its Trap-2 Opt-In Right as set forth above, the Trap-2 Product
shall not be included in the Co-Development, manufacture, Co-Commercialization
or Co-Marketing of IL-1 Products as contemplated by this Agreement, this
Agreement (including, without limitation, Sections 2.1, 2.4(c), 4.3, 4.4, 5.2,
5.4, 5.5, 6.1, 8.4, 13.3 and 15.2(a) and Articles III, VII and XI ) shall be of
no force or effect with respect to the Trap-2 Product, and Regeneron shall be
free to Develop and Commercialize the Trap-2 Product, alone or in collaboration
with any Third Party, without being subject to the provisions of this Agreement
(including, without limitation, Section 6.22).

                  5.5 Grant of Co-Development Rights.

                  (a)      Subject to the terms of this Agreement and any
Ancillary Agreement (including, without limitation, the exercise of the
applicable IL-1 Antibody Opt-In Rights and

                                      -31-

<PAGE>

the Trap-2 Opt-In Rights, the exceptions set forth in Section 6.2 and the rights
retained by the respective Parties hereunder in connection with IL-1 Products)
and subject to the terms of any license within any applicable Patent Rights,
each Party grants to the other Party and its Affiliates the sole right, together
with the granting Party and its Affiliates, to Co-Develop IL-1 Products in the
applicable Territory and for the applicable Term with respect to each IL-1
Product. For so long as a Party's rights of Co-Development under this Section
5.5(a) remain in effect with respect to a particular country with respect to a
particular IL-1 Product, the granting Party shall not grant any rights to, or
permit or authorize, any Third Party to Develop such IL-1 Product in such
country; provided that the foregoing shall not in any manner limit (a) the
granting Party's (or its Affiliates') activities in the Co-Development of
applicable IL-1 Product(s) as contemplated under this Agreement, or (b) the
granting Party's (or its Affiliates') Development activities with respect to
applicable IL-1 Product(s) outside of the applicable Territory.

                  (b)      The rights granted to Regeneron and its Affiliates
under Section 5.5(a) shall not be sublicensable. The rights granted to Novartis
and its Affiliates under Section 5.5(a) shall be sublicensable only with the
prior written consent of Regeneron, which consent shall not be unreasonably
withheld or delayed.

                                      -32-

<PAGE>

                  5.6 Co-Development of IL-1 Products. Subject to the terms of
this Agreement, the Parties shall undertake Development activities with respect
to the Trap-1 Product and any other IL-1 Product under the direction and
oversight of the Committees and in accordance with all applicable Consolidated
Co-Development Plans. Each Party shall use Commercially Reasonable Efforts to
carry out the Development activities assigned to it in such Consolidated
Co-Development Plans and to conduct all such activities in compliance with
applicable Laws, including, without limitation, Good Practices and export and
import control Laws. In carrying out Development activities hereunder with
respect to IL-1 Products, neither Party shall use the services of any Person
involved in the Development of any Trap-1 Product, IL-1 Antibody Product
(following the End of Phase II Development) or Trap-2 Product (following the End
of Phase II Development) which is not an IL-1 Product subject to the
Co-Development and/or Co-Commercialization rights pursuant to this Agreement, if
the use of such services would violate applicable Law.

                  5.7 Co-Development Plans. Subject to the terms of Article III
above and the applicable Ancillary Agreements, the JOC shall annually develop
Consolidated Co-Development Plans for IL-1 Products, for approval by the JSC.
Each Consolidated Co-Development Plan shall incorporate a Consolidated
Co-Development Budget and will set forth the plan for Development of each
applicable IL-1 Product on a calendar-year basis, including, without limitation:
(a) strategies for Developing and obtaining Approvals for such IL-1 Product; and
(b) allocation of responsibilities for Development activities between the
Parties, and/or to Third Party service providers to the extent permitted by the
applicable Consolidated Development Plan. Until such time as the Clinical Trials
and other activities described or referred to in the Preliminary Development
Plan attached hereto as SCHEDULE 8 (the "Preliminary Development Plan") have
been completed (unless the Preliminary Development Plan has been amended or
modified by the JSC in compliance with Article III (including Section 3.7(c)),
each Consolidated Co-Development Plan shall be consistent with the Preliminary
Development Plan and designed to complete as expeditiously as is commercially
reasonable such Clinical Trials and other activities described or referred to in
the Preliminary Development Plan.

                  5.8 Co-Development Reports. Within thirty (30) days after the
end of each quarter, Regeneron and Novartis shall each provide to the other
Party and to the JOC a written report (in electronic form) summarizing in
reasonable detail the material activities undertaken by such Party during such
quarter in connection with each Consolidated Co-Development Plan, together with
a detailed project-level statement of Development Costs incurred by such Party
during such quarter.

                  5.9 Loan Facilities for Trap-1 Product Development Costs.

                  (a)      2003 Development Costs Facility.

                  (i)      General. Novartis shall create an internal loan
         facility from which, subject to the further provisions hereof, it shall
         make advances to Regeneron, and from which Regeneron may draw funds in
         U.S. Dollars from time to time, in amounts that in the aggregate equal
         up to the share of Development Costs incurred in 2003 in connection
         with the Co-Development of Trap-1 Products for which Regeneron is
         responsible in accordance with SCHEDULE 4 of the Agreement (the "2003
         Regeneron Development Costs"). Such loan facility is referred to herein
         as the "2003 Facility", and such advances made thereunder are referred
         to herein collectively as the "2003 Facility Loans".

                                      -33-

<PAGE>

                  (ii)     Draws. To draw on the 2003 Facility, Regeneron shall
         submit a notice of funding (a "2003 Facility Funding Notice") to
         Novartis, signed by its Chief Financial Officer, specifying the amount
         of the requested advance (which shall not be less than $1 million per
         request) and certifying that such amount is in respect of 2003
         Regeneron Development Costs. 2003 Facility Loans shall be made by
         Novartis within twenty (20) Business Days after Novartis' receipt of a
         2003 Facility Funding Notice.

                  (iii)    Crediting of 2003 Facility Loans; Cash Disbursements.
         Immediately upon any 2003 Facility Loan being made, Regeneron hereby
         authorizes and directs Novartis to, and Novartis shall, credit the
         amount of such 2003 Facility Loan against 2003 Regeneron Development
         Costs, and each of Regeneron and Novartis acknowledges and agrees that
         there will be no cash disbursements of any 2003 Facility Loans to the
         extent they are so applied against 2003 Regeneron Development Costs;
         provided, however, that Novartis shall disburse to Regeneron (as
         Regeneron may direct Novartis in a 2003 Facility Funding Notice) all or
         a portion of any 2003 Facility Loan to the extent of 2003 Regeneron
         Development Costs actually incurred by Regeneron or its Affiliates. Any
         cash disbursement of a 2003 Facility Loan shall be made by Novartis by
         wire transfer of funds to an account specified by Regeneron in the 2003
         Facility Funding Notice within the time period provided in subparagraph
         (ii) above.

                  (iv)     Interest. The principal balance of 2003 Facility
         Loans outstanding shall bear interest from the date advanced at a rate
         per annum equal to the LIBOR Rate, plus 2.5%, and shall be compounded
         quarterly and, unless the 2003 Facility Loans have been accelerated in
         accordance with subparagraph (x) below, shall be payable as provided in
         subparagraph (v) below. For purposes of this Section 5.9 and Section
         6.23, "LIBOR Rate" shall mean the rate for three (3) months LIBOR (such
         period, with respect to any 2003 Facility Loan, any Post-2003 Facility
         Loan or any Promotional Expenses Facility Loan, the "LIBOR Period") for
         U.S. Dollars as reported by Datastream. Overdue principal and, to the
         extent permitted by law, overdue interest in respect of each 2003
         Facility Loan shall, in each case, bear interest at a rate per annum
         equal to the rate which is 2% in excess of the rate borne by such 2003
         Facility Loan. Interest which accrues under the immediately preceding
         sentence shall be payable on demand.

                  (v)      Repayment. The full amount of all outstanding 2003
         Facility Loans, and all accrued and unpaid interest thereon, shall be
         due and payable on July 1, 2004, provided, however that all outstanding
         2003 Facility Loans, and all accrued and unpaid interest thereon, shall
         be forgiven by Novartis, and the repayment obligation of Regeneron with
         respect thereto extinguished, automatically upon
         [***************************************************].

                  (vi)     Prepayment. Regeneron shall have the right to prepay
         any 2003 Facility Loans prior to the time required in subparagraph (v)
         above, without premium or penalty (except as provided below in
         subparagraph (viii)), in whole or in part, upon at least one Business
         Day's prior written notice (or telephonic notice confirmed by in
         writing, which may be by email) to Novartis of its intent to make such
         prepayment. The amount of any such prepayment (or repayment, whether
         pursuant to clause (v), (x) or (xi)) shall be applied pro rata against
         the principal amount of the then outstanding 2003 Facility Loans and
         accrued and unpaid interest thereon, in the order

                                      -34-

<PAGE>

         of their dates of disbursement, with any prepayment being first applied
         against the longest outstanding 2003 Facility Loan.

                  (vii)    Method of Repayment. Except as otherwise specifically
         provided herein, all payments of principal of, and accrued interest on,
         2003 Facility Loans shall be made in U.S. Dollars in immediately
         available funds to an account of Novartis specified by it to Regeneron,
         and shall be paid net of withholding taxes, if applicable.

                  (viii)   Breakage Cost. Regeneron shall compensate Novartis,
         upon the written request of Novartis, for any expenses or costs (a
         reasonably detailed calculation of which shall be provided by Novartis
         together with such written request) incurred by Novartis as a result of
         any prepayment pursuant to clause (vi) of any one or more 2003 Facility
         Loans having occurred on a date other than the last date of a LIBOR
         Period relating to such 2003 Facility Loan or 2003 Facility Loans.

                  (ix)     Termination of 2003 Facility. The 2003 Facility shall
         automatically terminate, and no further 2003 Facility Loans shall be
         advanced thereunder, upon the earlier of (A) the effective date of
         termination of the Agreement by Novartis with respect to the entire
         Trap-1 Territory for all Trap-1 Products and (B) the acceleration of
         the date of payment of 2003 Facility Loans pursuant to subparagraph (x)
         below.

                  (x)      Acceleration of 2003 Facility Loans. Novartis may, by
         notice to Regeneron, declare all principal of, and accrued and unpaid
         interest on, all 2003 Facility Loans due and payable, if a 2003
         Facility Loan Event of Default referred to in clause (A) or (B) below
         in this subparagraph (x) shall have occurred (and in such event upon
         such notice all such principal and unpaid interest shall immediately
         become due and payable) or if a 2003 Facility Loan Event of Default
         referred to in clause (C) below in this subparagraph (x) shall have
         occurred (and in such event upon such notice all such principal and
         interest shall be due and payable upon the first anniversary of the
         date of such notice), and if a 2003 Facility Loan Event of Default
         referred to in clause (D) of such definition shall have occurred, all
         such principal and interest shall automatically become due and payable.
         The occurrence of any of the following events shall constitute a "2003
         Facility Loan Event of Default": (A) Regeneron shall default in the
         payment when due of the principal of, and accrued and unpaid interest
         on, the 2003 Facility Loans, (B) the due date of indebtedness for
         borrowed money of Regeneron in an amount exceeding $10 million shall
         have been accelerated and Regeneron shall have failed to make payment
         thereof in full on the accelerated payment date, (C) the Agreement
         shall have been validly terminated in its entirety by Novartis pursuant
         to and in accordance with Section 19.5 of the Agreement and such
         termination shall be effective or (D) Regeneron shall commence a
         voluntary case concerning itself under the Bankruptcy Code, or an
         involuntary case under the Bankruptcy Code shall be commenced against
         Regeneron and the petition is not controverted within 10 days, or is
         not dismissed within 60 days, after commencement of the case, or a
         custodian (as defined in the Bankruptcy Code) is appointed for, or
         takes charge of, all or substantially all of the property of Regeneron,
         or Regeneron commences any other proceeding under any reorganization,
         arrangement, adjustment of debt, relief of debtors, dissolution,
         insolvency or liquidation or similar law of any jurisdiction whether
         now or hereafter in effect relating to Regeneron or there is commenced
         against Regeneron any such proceeding which remains undismissed for a
         period of 60 days, or Regeneron is adjudicated insolvent or bankrupt,
         or any order of relief or other order approving any such case or

                                      -35-

<PAGE>

         proceeding is entered, or Regeneron suffers any appointment of any
         custodian or the like for it or any substantial part of its property to
         continue undischarged or unstayed for a period of 60 days, or Regeneron
         makes a general assignment for the benefit of creditors, or any
         corporate action is taken by Regeneron for the purpose of effecting any
         of the foregoing.

                  (xi)     Right of Set-off. In addition to any rights now or
         hereafter granted under applicable law or otherwise, and not by way of
         limitation of any such rights, if any default by Regeneron in repaying
         when due all principal of, and accrued and unpaid interest on, all
         outstanding 2003 Facility Loans has occurred and is continuing,
         Novartis may, upon prior notice to Regeneron, set off against all such
         unpaid principal and interest any amount payable by Novartis to
         Regeneron under this Agreement.

                  (b)      Post-2003 Development Costs Facility.

                  (i)      General. Novartis shall create an internal loan
         facility from which, subject to the further provisions hereof, it shall
         make advances to Regeneron, and from which Regeneron may draw funds in
         U.S. Dollars from time to time, in amounts that in the aggregate equal
         up to the share of Development Costs incurred after 2003 in connection
         with the Co-Development of Trap-1 Products for which Regeneron is
         responsible in accordance with SCHEDULE 4 of the Agreement (the
         "Post-2003 Regeneron Development Costs"). Such loan facility is
         referred to herein as the "Post-2003 Facility", and such advances made
         thereunder are referred to herein collectively as the "Post-2003
         Facility Loans".

                  (ii)     Draws. To draw on the Post-2003 Facility, Regeneron
         shall submit a notice of funding (a "Post-2003 Facility Funding
         Notice") to Novartis, signed by its Chief Financial Officer, specifying
         the amount of the requested advance (which shall not be less than $1
         million per request) and certifying that such amount is in respect of
         Post-2003 Regeneron Development Costs. Post-2003 Facility Loans shall
         be made by Novartis within twenty (20) Business Days after Novartis'
         receipt of a Post-2003 Facility Funding Notice.

                  (iii)    Crediting of Post-2003 Facility Loans; Cash
         Disbursements. Immediately upon any Post-2003 Facility Loan being made,
         Regeneron hereby authorizes and directs Novartis to, and Novartis
         shall, credit the amount of such Post-2003 Facility Loan against
         Post-2003 Regeneron Development Costs, and each of Regeneron and
         Novartis acknowledges and agrees that there will be no cash
         disbursements of any Post-2003 Facility Loans to the extent they are so
         applied against Post-2003 Regeneron Development Costs; provided,
         however, that Novartis shall disburse to Regeneron (as Regeneron may
         direct Novartis in a Post-2003 Facility Funding Notice) all or a
         portion of any Post-2003 Facility Loan to the extent of Post-2003
         Regeneron Development Costs actually incurred by Regeneron or its
         Affiliates. Any cash disbursement of a Post-2003 Facility Loan shall be
         made by Novartis by wire transfer of funds to an account specified by
         Regeneron in the Post-2003 Facility Funding Notice within the time
         period provided in subparagraph (ii) above.

                  (iv)     Interest. The principal balance of Post-2003 Facility
         Loans outstanding shall bear interest from the date advanced at a rate
         per annum equal to the LIBOR Rate, plus 2.5%, and shall be compounded
         quarterly and, unless the Post-2003

                                      -36-

<PAGE>

         Facility Loans have been accelerated in accordance with subparagraph
         (x) below, shall be payable as provided in subparagraph (v) below.
         Overdue principal and, to the extent permitted by law, overdue interest
         in respect of each Post-2003 Facility Loan shall, in each case, bear
         interest at a rate per annum equal to the rate which is 2% in excess of
         the rate borne by such Post-2003 Facility Loan. Interest which accrues
         under the immediately preceding sentence shall be payable on demand.

                  (v)      Repayment. The full amount of all outstanding
         Post-2003 Facility Loans, and all accrued and unpaid interest thereon,
         will be due and payable five (5) years after the earlier of (A) the
         first Launch of a Trap-1 Product in the United States or Europe and (B)
         the effective date of termination of the Agreement by Novartis with
         respect to the entire Trap-1 Territory for all Trap-1 Products.

                  (vi)     Prepayment. Regeneron shall have the right to prepay
         any Post-2003 Facility Loans prior to the time required in subparagraph
         (v) above, without premium or penalty (except as provided below in
         subparagraph (viii)), in whole or in part, upon at least one Business
         Day's prior written notice (or telephonic notice confirmed by in
         writing, which may be by email) to Novartis of its intent to make such
         prepayment. The amount of any such prepayment (or repayment, whether
         pursuant to clause (v), (x) or (xi)) shall be applied pro rata against
         the principal amount of the then outstanding Post-2003 Facility Loans
         and accrued and unpaid interest thereon, in the order of their dates of
         disbursement, with any prepayment being first applied against the
         longest outstanding Post-2003 Facility Loan.

                  (vii)    Method of Repayment. Except as otherwise specifically
         provided herein, all payments of principal or accrued interest on
         Post-2003 Facility Loans shall be made in U.S. Dollars in immediately
         available funds to an account of Novartis specified by it to Regeneron,
         and shall be paid net of withholding taxes, if applicable.

                  (viii)   Breakage Cost. Regeneron shall compensate Novartis,
         upon the written request of Novartis, for any expenses or costs (a
         reasonably detailed calculation of which shall be provided by Novartis
         together with such written request) incurred by Novartis as a result of
         any prepayment pursuant to clause (vi) of any one or more Post-2003
         Facility Loans having occurred on a date other than the last date of a
         LIBOR Period relating to such Post-2003 Facility Loan or Post-2003
         Facility Loans.

                  (ix)     Termination of Post-2003 Facility. The Post-2003
         Facility shall automatically terminate, and no further Post-2003
         Facility Loans shall be advanced thereunder, upon the early of (A) the
         effective date of termination of the Agreement by Novartis with respect
         to the entire Trap-1 Territory for all Trap-1 Products and (B) the
         acceleration of the date of payment of Post-2003 Facility Loans
         pursuant to subparagraph (x) below.

                  (x)      Acceleration of Post-2003 Facility Loans. Novartis
         may, by notice to Regeneron, declare all principal of, and accrued and
         unpaid interest on, all Post-2003 Facility Loans due and payable, if a
         Post-2003/Promotional Expense Event of Default referred to in clause
         (A) or (B) below in this subparagraph (x) shall have occurred (and in
         such event upon such notice all such principal and unpaid interest
         shall immediately become due and payable) or if a Post-2003/Promotional
         Expense Event of Default referred to in clause (C) below in this
         subparagraph (x) shall have occurred (and in such event upon such
         notice all such principal and interest shall be due and

                                      -37-

<PAGE>

         payable upon the first anniversary of the date of such notice), and if
         a Post-2003/Promotional Expense Event of Default referred to in clause
         (D) of such definition shall have occurred, all such principal and
         interest shall automatically become due and payable. The occurrence of
         any of the following events shall constitute an "Post-2003/Promotional
         Expense Event of Default": (A) Regeneron shall default in the payment
         when due of all principal of, and accrued and unpaid interest on, the
         Promotional Expense Facility Loans or the Post-2003 Facility Loans, (B)
         the due date of indebtedness for borrowed money of Regeneron in an
         amount exceeding $10 million shall have been accelerated and Regeneron
         shall have failed to make payment thereof in full on the accelerated
         payment date, (C) the Agreement shall have been validly terminated in
         its entirety by Novartis pursuant to and in accordance with Section
         19.5 of the Agreement and such termination shall be effective or (D)
         Regeneron shall commence a voluntary case concerning itself under the
         Bankruptcy Code or an involuntary case under the Bankruptcy Code shall
         be commenced against Regeneron and the petition is not controverted
         within 10 days, or is not dismissed within 60 days, after commencement
         of the case, or a custodian (as defined in the Bankruptcy Code) is
         appointed for, or takes charge of, all or substantially all of the
         property of Regeneron, or Regeneron commences any other proceeding
         under any reorganization, arrangement, adjustment of debt, relief of
         debtors, dissolution, insolvency or liquidation or similar law of any
         jurisdiction whether now or hereafter in effect relating to Regeneron
         or there is commenced against Regeneron any such proceeding which
         remains undismissed for a period of 60 days, or Regeneron is
         adjudicated insolvent or bankrupt, or any order of relief or other
         order approving any such case or proceeding is entered, or Regeneron
         suffers any appointment of any custodian or the like for it or any
         substantial part of its property to continue undischarged or unstayed
         for a period of 60 days, or Regeneron makes a general assignment for
         the benefit of creditors, or any corporate action is taken by Regeneron
         for the purpose of effecting any of the foregoing.

                  (xi)     Right of Set-off. In addition to any rights now or
         hereafter granted under applicable law or otherwise, and not by way of
         limitation of any such rights, any default by Regeneron in repaying
         when due all principal of, and accrued and unpaid interest on, all
         outstanding Post-2003 Facility Loans has occurred and is continuing,
         Novartis may, upon prior notice to Regeneron, set off against all such
         unpaid principal and interest any amount payable by Novartis to
         Regeneron under the Agreement.

                  (c)      Survival. This Section 5.9 shall survive termination
of this Agreement.

                                   ARTICLE VI

                              CO-COMMERCIALIZATION

                  6.1 Grant of Co-Commercialization Rights.

                  (a)      Subject to the terms of this Agreement and any
Ancillary Agreement (including, without limitation, the exercise of the IL-1
Antibody Opt-In Rights and the Trap-2 Opt-In Rights, as applicable, the
exceptions set forth in Section 6.2 and the rights retained by the respective
Parties hereunder in connection with IL-1 Products) and subject to the terms of
any license within any applicable Patent Rights, each Party grants to the other
Party and its Affiliates the sole right, together with the granting Party and
its Affiliates, to Co-

                                      -38-

<PAGE>

Commercialize IL-1 Products in each of the Co-Commercialization Countries for
the applicable Term in each such Co-Commercialization Country. For so long as a
Party's rights of Co-Commercialization under this Section 6.1(a) remain in
effect with respect to any Co-Commercialization Country, the granting Party
shall not grant any rights to, or permit or authorize, any Third Party to
Commercialize, promote or Detail any applicable IL-1 Product in such
Co-Commercialization Country; provided that the foregoing shall not in any
manner limit (a) the granting Party's (or its Affiliates') activities in the
Co-Commercialization of applicable IL-1 Product(s) as contemplated under this
Agreement, (b) the granting Party's (or its Affiliates') Commercialization
activities with respect to applicable IL-1 Product(s) outside of the applicable
Territory, or (c) the granting Party's (or its Affiliates') right to permit or
authorize any Third Party to serve as a Distributor for the applicable IL-1
Product.

                  (b)      The rights granted to Regeneron and its Affiliates
under Section 6.1(a) shall not be sublicensable. The rights granted to Novartis
and its Affiliates under Section 6.1(a) shall be sublicensable to Distributors
of Novartis (but not with respect to the Commercialization of IL-1 Products in
any country listed on SCHEDULE 10) and otherwise only with the prior written
consent of Regeneron, which consent shall not be unreasonably withheld or
delayed. For the avoidance of doubt, Regeneron may withhold such consent if it
reasonably determines such sublicense would reduce Regeneron's financial return
from the sale of the applicable IL-1 Product in the applicable country.

                  (c)      The provisions of Sections 6.4 to 6.20 inclusive
(such provisions, the "Co-Commercialization Provisions") shall apply in each
Co-Commercialization Country.

                  6.2 Exceptions to the Grant of Co-Commercialization Rights.

                  (a)      The Parties may, from time to time, jointly agree, by
unanimous affirmative vote of all members of the JSC, to exclude a
Co-Commercialization Country from the applicable Territory.

                  (b)      The Parties may, from time to time, mutually agree to
designate certain Co-Commercialization Countries as Exclusive Countries for
either Novartis or Regeneron. The commercial terms relating to marketing in such
Exclusive Countries will be as the Parties may at the time mutually agree at
such time.

                  (c)      The Parties may, from time to time, mutually agree to
exclude, by amendment of the applicable definition of "Territory" in accordance
with Section 20.5, certain Co-Commercialization Countries from the applicable
Territory; provided, however, that such countries may also be reinstated to the
applicable Territory by amendment of the applicable definition of "Territory" in
accordance with Section 20.5.

                  (d)      No later than ninety (90) days prior to the date of
Launch of an IL-1 Product in a Co-Commercialization Country, the Parties may
agree, through the JSC, that it would be in the best interests of both Parties
to Co-Market the IL-1 Product in such Co-Commercialization Country, in which
case such Co-Commercialization Country shall be deemed forthwith to be a
Co-Marketing Country and shall be subject to a separate Co-Marketing Agreement
between the Parties.

                  6.3 Commercialization of IL-1 Products in Co-Marketing
Countries. In the event (and for so long as) the Parties are not permitted under
local Law to Co-Promote or Co-Brand IL-1 Products in any country in the
applicable Territory, but are permitted to Co-

                                      -39-

<PAGE>

Market the IL-1 Products in such country (i.e., a "Co-Marketing Country"), then
the Parties (in the case of Regeneron, directly, or through a Third-Party
licensee) shall Co-Market the IL-1 Products in such Co-Marketing Country in
accordance with a separate Co-Marketing Agreement to be agreed in good faith
between the Parties and, to the extent not prohibited by applicable Law in such
Co-Marketing Country in accordance with (a) the obligations set forth in the
Co-Commercialization Provisions applicable to the Co-Commercialization Countries
and (b) the other provisions of this Agreement. In the event any such provisions
of this Agreement are prohibited by applicable Law in a Co-Marketing Country and
are not covered by the Co-Marketing Agreement, then such provision shall be
considered a Severed Clause under Section 20.7 solely with respect to such
Co-Marketing Country. If prior to a Registration Filing in a Co-Marketing
Country, or any mutually agreed upon time thereafter, Regeneron notifies
Novartis that it does not intend to Co-Market the applicable IL-1 Product in
such Co-Marketing Country, then Novartis shall have the exclusive right to
Develop and Commercialize the IL-1 Product in such Co-Marketing Country;
provided that for purposes of determining payment of Development Costs and
determining the Target Profit Split, the Country shall be treated as a
Co-Commercialization Country hereunder.

                  6.4 Commercialization of IL-1 Products in Co-Commercialization
Countries. Novartis and Regeneron (through their respective Affiliates where
appropriate) shall Co-Promote and Co-Brand IL-1 Products under the applicable
Product Trademarks in each Co-Commercialization Country during the applicable
Term in accordance with the then-current JSC-approved Consolidated
Co-Commercialization Plan, Consolidated Co-Commercialization Budget, Country
Co-Commercialization Plans and Country Co-Commercialization Budgets, using
substantially equivalent quality of efforts and resources. Each Party shall use,
or shall cause its local Affiliates to use, Commercially Reasonable Efforts in
performing such obligations. Notwithstanding any other provision of this
Agreement, the Parties shall not be required to Launch any IL-1 Product in any
Co-Commercialization Country unless and until: (a) full commercial channels of
distribution have been established in the applicable country; and (b) IL-1
Product inventory sufficient to meet reasonably anticipated levels of demand has
been procured, it being understood and agreed that, upon the terms and subject
to the conditions of this Agreement, the Parties will use Commercially
Reasonable Efforts to finally establish such distribution channels and procure
such inventory so the Launch of such IL-Product will not be delayed.

                  6.5 Co-Commercialization Plans. The initial Consolidated
Co-Commercialization Plan and Consolidated Co-Commercialization Budget for each
IL-1 Product will be prepared by the JOC for JSC approval at least
[************************]. The Consolidated Co-Commercialization Plan and
Consolidated Co-Commercialization Budget for each subsequent calendar year shall
be prepared by the Joint Operating Committee to enable JSC approval at least
[**************************]. The Consolidated Co-Commercialization Plan and
Consolidated Co-Commercialization Budget shall be based upon annual Country
Co-Commercialization Plans and Country Co-Commercialization Budgets prepared by
the Joint Operating Committee which will set forth the detailed plan for
Commercialization of the IL-1 Product in the Co-Commercialization Countries on a
calendar-year basis, including:

                  (a)      strategies for the Detailing and Co-Promotion or
Co-Branding, as applicable, of the IL-1 Products, including recommended target
Professionals for such activities;

                                      -40-

<PAGE>

                  (b)      allocation between the Parties of responsibilities
for marketing, sales and promotional activities (except that in the case of
Detailing, such allocation shall be preliminary and shall be finally determined
as provided in Section 6.10(a));

                  (c)      anticipated marketing, sales and promotion efforts by
each Party (or its Affiliates) (including number and position of Details, and
sampling activities);

                  (d)      market and sales forecasts in a form to be agreed
between the Parties via the Joint Operating Committee;

                  (e)      advertising, public relations and other promotional
programs and sampling, to be used in the Co-Promotion and Co-Branding;

                  (f)      medical affairs programs, including professional
symposia and other educational activities, and medical affairs studies based
upon Joint Operating Committee-approved protocols;

                  (g)      Phase IV Clinical Trials (other than Phase IV
Clinical Trials intended to support or maintain a Registration Filing for a
particular IL-1 Product, including by way of example such Phase IV Clinical
Trials as which are intended to support expanded labeling for such IL-1 Product
or to satisfy requirements imposed by Regulatory Authorities in connection with
Approvals for such IL-1 Product) in the Co-Commercialization Countries relating
to the IL-1 Products, which Phase IV Clinical Trials shall be based upon
JOC-approved protocols; and

                  (h)      as appropriate, a training plan for the Parties'
Qualified Sales Representatives.

In addition to the detailed plan and budget for the next upcoming calendar year,
each Country Co-Commercialization Plan, Country Co-Commercialization Budget,
Consolidated Co-Commercialization Plan and Consolidated Co-Commercialization
Budget will include an outline of the projected plan and estimated budget for
the following calendar year.

                  6.6 Co-Commercialization Reports and Detailing Reports.

                  (a)      Within thirty (30) days after the end of each
quarter, Regeneron and Novartis shall each provide to the other Party and to the
JOC, in electronic form a Country Co-Commercialization Report and a Consolidated
Co-Commercialization Report.

                  (b)      Regeneron and Novartis shall also each provide to the
other Party and to the JOC, within thirty (30) days following the end of each
quarter commencing with the first quarter during the Contract Year in which the
Launch of an IL-1 Product occurs, a written report setting forth, in such detail
and form as the JOC shall require, the PDEs and number of Details made by such
Party's Qualified Sales Representatives in each Co-Commercialization Country
during such quarter and setting out a proposed plan for future Detailing efforts
to be performed by such Party as requested by the JOC (the "Detailing Report").
In addition, each Party shall on a periodic and reasonably current basis, keep
the JOC informed regarding the activities of its Qualified Sales Representatives
in promoting the IL-1 Product, including information relating to market
developments, acceptance of the IL-1 Product, complaints and similar
information.

                                      -41-

<PAGE>

                  6.7 IL-1 Product Pricing and Pricing Approvals. Novartis shall
present to the JSC proposals for the terms and conditions of sale of each IL-1
Product in each Co-Commercialization Country, including proposed IL-1 Product
pricing, pricing changes, requests for reimbursements, and parameters for any
discount or rebate programs. Final decisions concerning IL-1 Product conditions
of sale, pricing, and discount/rebate programs shall be made by the JSC or the
applicable Country Co-Commercialization Committee, if any. In those
Co-Commercialization Countries where Price Approval is required or determined by
the JSC to be desirable, Novartis will be solely responsible for using
Commercially Reasonable Efforts to seek and obtain such approval, provided that
Regeneron shall have the right to participate in any material meetings or the
preparation of any material submissions to Governmental Authorities in
connection therewith. Regeneron (or its local Affiliate) shall be responsible
for any reasonable assistance required by Novartis (or its local Affiliate) for
the purposes of obtaining such Pricing Approval. In the event that, whether by
failure of Novartis to exercise the Trap-2 Opt-In Rights or as a result of a
termination of this Agreement with respect to any Trap-1 Product, the IL-1
Antibody Product or the Trap-2 Product, Regeneron Commercializes any of the
Trap-1 Product, the IL-1 Antibody Product or the Trap-2 Product outside of the
collaboration contemplated by this Agreement, Regeneron shall, to the extent
necessary to comply with applicable Law, institute screening procedures to
ensure that Regeneron's representation on the applicable Committees will not
disclose or exchange pricing information or other competitively sensitive
information with the Regeneron personnel responsible for Commercialization of
such products outside of the collaboration contemplated by this Agreement.

                  6.8 Booking of Sales and IL-1 Product Distribution. Novartis
(or its local Affiliate) shall invoice and book all sales of the IL-1 Product in
the Co-Commercialization Countries and shall appropriately record all sales of
the IL-1 Product in the Co-Commercialization Countries. Novartis (or its local
Affiliate) shall also be responsible for the distribution of the IL-1 Product in
the Co-Commercialization Countries and for paying Medicaid and other
governmental rebates which are due and owing with respect to the IL-1 Product in
the Co-Commercialization Countries.

                  6.9 Field Forces.

                  (a)      Field Force Activities. In Co-Promoting and
Co-Branding IL-1 Products in the Co-Commercialization Countries, each Party
(through its local Affiliates, as appropriate) shall provide such internal
administrative and logistical support of its Qualified Sales Representative
field force as is usual and customary in the pharmaceutical industry in the
relevant Co-Commercialization Countries, consistent with its normal practices.
Each Party (through its local Affiliates, as appropriate) shall diligently
Co-Promote or Co-Brand, as applicable, IL-1 Products in such country in
accordance with the then-applicable Joint Steering Committee-approved Country
Co-Commercialization Plans. Such efforts shall include, without limitation,
performing the following types of activities, each in accordance with the
approved Country Co-Commercialization Plan:

                  (i)      training, maintaining and managing Qualified Sales
         Representatives to Detail Professionals and potential purchasers,
         including target physicians;

                  (ii)     distributing Promotional Materials through each
         Party's respective Qualified Sales Representatives or other customary
         methods;

                                      -42-

<PAGE>

                  (iii)    subject to Section 6.18, responding to inquiries
         regarding the IL-1 Products (other than consumer and medical
         inquiries);

                  (iv)     providing administrative support services (such as an
         electronic territory management system, where applicable); and

                  (v)      setting, monitoring and implementing Qualified Sales
         Representative incentives related to the Co-Promotion, Co-Branding and
         sale of the IL-1 Products,

         provided, however, that in carrying out the foregoing activities
hereunder with respect to IL-1 Products, neither Party shall use the services of
any Person involved in the Commercialization of any Trap-1 Product, IL-1
Antibody Product or Trap-2 Product which is not an IL-1 Product subject to
Co-Development and/or Co-Commercialization rights pursuant to this Agreement, if
the use of such services would violate applicable Law.

                  (b)      Cooperation. The JOC shall coordinate the
Co-Promotion or Co-Branding, as the case may be, of each IL-1 Product by
Novartis, Regeneron, their respective local Affiliates and their respective
Qualified Sales Representatives in each Co-Commercialization Country. The
Parties will discuss efforts to mirror their respective field forces, field
force territories and management structures in each Co-Commercialization
Country. The Parties will cooperate in the conduct of such activities with
respect to scheduling, geographical allocation, alignment of the weighting of
the IL-1 Product-related incentives within the Qualified Sales Representatives'
overall incentives, and Professional or other customer targeting in order to
optimize sales and profits under the Consolidated Co-Commercialization Plan and
the relevant Country Co-Commercialization Plan. Without limiting the generality
of the foregoing, the Parties will share, and, to the extent appropriate,
cooperate with respect to implementing consistent, policies and procedures with
respect to the manner in which Details are conducted. Following the Launch date,
the Parties will discuss whether it is advisable for Regeneron to adopt and/or
utilize Novartis's Sales Infrastructure Elements as part of the Consolidated
Co-Commercialization Plan. Novartis shall be compensated for any services or
resources provided in connection with its sharing of the Novartis Sales
Infrastructure Elements on such terms mutually agreed upon by the Parties.

                  (c)      Contract Sales Force. Either Party shall be entitled
to discharge its annual Detailing obligations for any IL-1 Product in any
Co-Commercialization Country by engaging a Contract Sales Force. If a Party (or
its local Affiliate) retains a Contract Sales Force in a Co-Commercialization
Country, that Party (or its local Affiliate) will be responsible for all costs
associated with retaining such Contract Sales Force and for the Contract Sales
Force's compliance with this Agreement, including, without limitation, the
training and monitoring of such Contract Sales Force and ensuring compliance
with all applicable Laws.

                  6.10 Detailing.

                  (a)      Detailing Efforts and Reimbursement. Each Country
Co-Commercialization Plan shall specify the number of Details to be provided by
each of the Parties in the applicable Co-Commercialization Country. For each
Co-Commercialization Country, not less than [******************] prior to the
first anticipated Launch of each IL-1 Product in the applicable
Co-Commercialization Country, Regeneron will provide to Novartis and the JSC a
binding notice of the number of Details that Regeneron commits to

                                      -43-

<PAGE>

deliver with respect to such IL-1 Product in each Co-Commercialization Country
during the year covered by the Consolidated Co-Commercialization Plan then in
effect (such number of Details divided by the total number of Details provided
for in the then current Consolidated Co-Commercialization Plan being referred to
as the "Regeneron Commitment Level"), which shall in no event exceed the
applicable percentage for Regeneron set forth in SCHEDULE 2 (such percentage
being the "Maximum Regeneron Effort"). Such notice shall be accompanied by a
plan setting forth Regeneron's plan (which shall be developed in cooperation
with Novartis and shall be intended to coordinate and integrate the Parties'
respective Detailing activities) for ensuring that, by no later than the Launch
date of such IL-1 Product, it will have in place a field force of Qualified
Sales Representatives and appropriate field force infrastructure as contemplated
by Section 6.9(a) to perform no less than the number of Details required to
satisfy the Regeneron Commitment Level. In each Co-Commercialization Country,
Novartis shall perform all Details for each IL-1 Product above the Regeneron
Commitment Level. In the event that the Regeneron Commitment Level is less than
the Maximum Regeneron Effort, Regeneron shall reimburse Novartis for the cost of
performing any PDE's required to make up the difference between the Maximum
Regeneron Effort and the Regeneron Commitment Level at [*********************].

                  (b)      Changes in Regeneron Detailing Commitment. Regeneron
may change the Regeneron Commitment Level on a product-by-product and
country-by-country basis by giving [*********************] notice in writing to
Novartis and to the JSC; provided, however, that in no event may the Regeneron
Commitment Level exceed the Maximum Regeneron Effort, and provided, further,
that any increase in the Regeneron Commitment Level shall not be effective if
the JSC reasonably determines that such change would have an adverse effect on
the Parties' shared goal of optimizing the commercial potential of the
applicable IL-1 Product.

                  (c)      Performance of Details. Each Party's (or its local
Affiliate's) Qualified Sales Representatives shall Detail the IL-1 Products in
each Co-Commercialization Country in accordance with the approved Country
Co-Commercialization Plan. Each Party shall be obligated to perform at least the
required number of PDEs for the IL-1 Products set forth in the Country
Co-Commercialization Plan. Unless otherwise agreed by the Parties through the
JSC on a country-by-country basis, [*********************************].

                  (d)      Projected PDE Shortfalls. There may be occasions when
a Party (or its local Affiliate) believes in good faith that, notwithstanding
Commercially Reasonable Efforts, it will be unable to perform the number of
Details for an IL-1 Product in one or more Co-Commercialization Countries for
which it is responsible under the then-current Country Co-Commercialization
Plans. In such an event, such Party (or its local Affiliate) (the "Shortfall
Party") shall promptly give written notice to the other Party (or its local
Affiliate) and the JOC that it will not be able to meet its Detailing
obligations together with notice of the projected shortfall in PDEs. Upon
receipt of such notice, the other Party (or its local Affiliate) shall have the
option, exercisable in its sole discretion, to perform such additional PDEs, in
which case (i) the Shortfall Party's minimum PDE obligation under the
then-current Country Co-Commercialization Plan for purposes of determining any
penalties or additional compensation under Section 6.10(e) shall be reduced by
the number of additional PDEs agreed to be performed by the other Party for that
year, and (ii) the Shortfall Party shall reimburse the other Party for the cost
of performing the additional PDEs during the relevant calendar year on a
product-by-product and country-by-country basis, based upon
[**********************].

                                      -44-

<PAGE>

                  (e)      Failure to Perform PDEs. In the event that either
Party (or its local Affiliate) fails to perform [**********************] of its
agreed Detailing obligations for an IL-1 Product in any Co-Commercialization
Country for any calendar year (as set forth in the then-current Joint Steering
Committee-approved Country Co-Commercialization Plan for such country), unless
Section 6.10(d) is applicable with respect to such failure (in which event this
Section 6.10(e) shall not apply with respect to such failure) the Party failing
to perform (or its applicable local Affiliate) shall pay to the other Party (or
its applicable local Affiliate) an amount determined as set forth in SCHEDULE 5.

                  (f)      Detailing; Record Keeping. Each Party (through its
local Affiliates where appropriate) shall maintain records of its Detailing of
the IL-1 Products in the Co-Commercialization Countries in a manner sufficient
to permit the determination of the number and position of Details performed by
such Party with respect to the IL-1 Products in each Co-Commercialization
Country. Any shortfall by a Party (or its Affiliates) in performing the number
of annual PDEs specified in the Joint Steering Committee-approved Country
Co-Commercialization Plan shall, at the end of each year, be addressed in
accordance with the provisions of this Section 6.10. Each Party shall adopt a
code of conduct for its sales force strictly and explicitly prohibiting
falsification of Detail reporting and imposing penalties for non-compliance,
which penalties shall be enforced.

                  (g)      PDE Reporting. Each Party (through its local
Affiliates where appropriate) shall provide the other Party and the JOC with
periodic reports of the number and position of Details actually performed by it
for each IL-1 Product in each Co-Commercialization Country. Such PDE reports
shall be provided quarterly, within thirty (30) days after the close of the
calendar quarter covered by the report; provided that more frequent reporting
may be required as determined by the JOC. Notwithstanding the foregoing, during
the first two (2) years immediately following the Launch of each IL-1 Product in
each Co-Commercialization Country, such PDE reports shall be provided by each
Party on a monthly basis, within sixty (60) days after the end of each month,
with respect to the relevant Co-Commercialization Country.

                  6.11 Training.

                  (a)      Each Party (through its local Affiliates where
appropriate) shall, at its own expense, comply with the training plan contained
in any Consolidated Co-Commercialization Plan or Country Co-Commercialization
Plan.

                  (b)      Prior to the Launch of an IL-1 Product in any
Co-Commercialization Country, the Parties (through their local Affiliates where
appropriate) shall jointly develop sales training materials for use in training
each Party's Qualified Sales Representatives. The Parties (through their local
Affiliates where appropriate) will thereafter cause their training personnel to
train their field Qualified Sales Representatives with such training materials
and Promotional Materials.

                  (c)      If either Party (including through their respective
local Affiliates) organizes IL-1 Product-related meetings of its employees (such
as launch meetings or periodic briefings of its Qualified Sales
Representatives), it will make Commercially Reasonable Efforts to give the other
Party (or its local Affiliate) advance notice of such meetings. If requested by
the other Party (or its local Affiliate), the Party (or its local Affiliate)
organizing such meetings will permit representatives of the other Party (or its
local Affiliate) to attend and participate in such meetings or such portions
thereof which relate to

                                      -45-

<PAGE>

the Co-Commercialization of the IL-1 Products at their own cost. In such event,
the Party organizing such meeting shall keep the IL-1 Product-related portions
of such meetings independent from other matters.

                  (d)      In a manner determined by the Joint Operating
Committee, the Parties (through their local Affiliates where appropriate) will
coordinate the Detailing, sales meetings, contacts with wholesalers and
retailers, targeting of healthcare organizations, speaker programs and, as
appropriate, medical affairs and/or support activities for relevant Phase IV
Clinical Trials as provided in the Consolidated Co-Commercialization Plan and
relevant Country Co-Commercialization Plan.

                  6.12 Promotional Materials. The Parties and their Affiliates
shall only use JOC approved Promotional Materials and only conduct marketing and
promotional activities for the IL-1 Products which, in each case, are provided
for in the relevant approved Country Co-Commercialization Plan. The Parties will
jointly prepare Promotional Materials for the IL-1 Products which are intended
for use within the Co-Commercialization Countries. Novartis will have primary
responsibility, with Regeneron's participation, for the preparation of
Promotional Materials intended for use in a Co-Commercialization Country, and
shall ensure that all such Promotional Materials are consistent with the
approved Consolidated Co-Commercialization Plan and Country Co-Commercialization
Plan, and comply with all applicable Laws. Novartis shall be responsible for the
distribution of Promotional Materials for use in the Co-Commercialization
Country, shall ensure that Regeneron's local Affiliates have equal access to all
Promotional Materials for use in the Co-Commercialization Country, and shall
treat its own Affiliates and those of Regeneron equally in connection with the
distribution of Promotional Materials in accordance with the approved Country
Co-Commercialization Plan. Promotional Materials which constitute Detail
handouts for distribution to Professionals shall be allotted according to each
Party's (or its local Affiliate's) Detail requirements under the approved
Country Co-Commercialization Plan. Promotional Materials for use in Detail
presentations and retained by the Qualified Sales Representatives shall be
allotted according to the number of Qualified Sales Representatives to be
engaged by each Party (or their respective local Affiliates) under the approved
Country Co-Commercialization Plan for the relevant country. The Parties shall
jointly own all rights to all Promotional Materials, including all copyrights
thereto. All locally generated Promotional Materials for a Co-Commercialization
Country shall be maintained in confidence and shall not be disclosed or
distributed to Third Parties, until such time as they have been reviewed and
approved under a core review process to be established by the Joint Operating
Committee.

                  6.13 Promotional Claims/Compliance. Neither Party (nor any of
their respective Affiliates) shall make any medical or promotional claims for
any IL-1 Product beyond the scope of the relevant Approval(s) then in effect for
such IL-1 Product or that are beyond the scope of, or inconsistent with, the
approved Consolidated Co-Commercialization Plan, Country Co-Commercialization
Plans and Promotional Materials. When distributing information related to any
IL-1 Product or its use (including information contained in scientific articles,
reference publications and publicly available healthcare economic information),
each Party (and their respective Affiliates) shall comply with all applicable
Laws (and with respect to the U.S., in accordance with the Pharmaceutical
Research Manufacturers of America Code on Interactions with Healthcare
Professionals).

                  6.14 Samples. In support of Regeneron's Detailing and
promotional activities, Novartis shall provide Regeneron with IL-1 Product
samples as required in the

                                      -46-

<PAGE>

Consolidated Co-Commercialization Plan. Samples shall be allotted according to
the Detailing requirements of each of Novartis and Regeneron under the
Consolidated Co-Commercialization Plan and applicable Country Consolidated
Co-Commercialization Plan and Laws. Novartis shall supply its local Affiliate in
each Co-Commercialization Country with the total number of samples required for
such Co-Commercialization Country and such Novartis Affiliates shall
subsequently forward to Regeneron at a designated location the number of samples
to which Regeneron is entitled under the Consolidated Co-Commercialization Plan
and applicable Country Consolidated Co-Commercialization Plan. Novartis and
Regeneron (and their respective Affiliates) shall use samples strictly in
accordance with the then-applicable, approved Consolidated Co-Commercialization
Plan and Country Co-Commercialization Plan and shall store and distribute
samples in full compliance with applicable Laws, including the requirements of
the PDMA. Regeneron (and its local Affiliates) will maintain those records
required by the PDMA and all other Laws and shall allow representatives of
Novartis to inspect such records and storage facilities for the IL-1 Product
samples on request. Subject to receipt of necessary information from the other
Party, the Lead Regulatory Party shall be solely responsible for the filing with
the FDA of any necessary reports in connection with the PDMA.

                  6.15 Cost of Field Sales Promotion. Each Party shall be solely
responsible for all costs and expenses incurred by it in providing the personnel
necessary to provide the services described in this Article VI (including,
without limitation, salaries, benefits, cars and customer relationship money for
such personnel), other than as provided in Sections 6.10(a), (d) and (e).

                  6.16 Managed Care and Institutional Customers. Novartis shall
be responsible for all interactions with Managed Care and Institutional
Customers and for the implementation of contracting strategies and procedures
developed by the JOC with respect to Managed Care and Institutional Customers.

                  6.17 Shared Promotion Expenses. Novartis (or its relevant
local Affiliate with respect to such Affiliate's Co-Commercialization Country)
and Regeneron (or its relevant local Affiliate with respect to such Affiliate's
Co-Commercialization Country) shall each bear the portion of Shared Promotion
Expenses accrued in implementing each applicable Consolidated
Co-Commercialization Plan.

                  6.18 Medical and Consumer Inquiries. Each Party (through its
local Affiliates, as appropriate) shall be entitled to respond to routine
medical and consumer inquiries received by it concerning the IL-1 Products;
provided that all such responses shall be in accordance with the approved IL-1
Product labeling information and, as appropriate, the recommendations of the
JOC, and that all such inquiries and responses shall be shared, as appropriate,
with the other Party to the extent not prohibited by applicable Law. Any
non-standard inquiries should be directed to the attention of such person(s) as
is designated pursuant to Section 7.6(a).

                  6.19 Compliance with Laws. Each Party shall use, and shall
ensure that its Affiliates and sublicensees use, Commercially Reasonable Efforts
to carry out its Commercialization activities with respect to IL-1 Products in
material compliance with all applicable Laws governing the conduct of such
activities, including, without limitation, all applicable export and import
control laws.

                                      -47-

<PAGE>

                  6.20 Phase IV Clinical Trials. Subject to the provisions of
this Agreement, the Parties shall use Commercially Reasonable Efforts to comply
with any Phase IV Clinical Trial obligations, with respect to any IL-1 Product
in any country in the applicable Territory, imposed by applicable Law or
pursuant to the applicable Approvals. The Parties shall use Commercially
Reasonable Efforts to conduct Phase IV Clinical Trials with respect to any IL-1
Product in any country in the applicable Territory which has been recommended by
the JOC and which has been approved by the Joint Steering Committee.

                  6.21 Market Exclusivity Extensions. Each Party shall use
Commercially Reasonable Efforts to maintain and, to the extent available,
legally extend the Market Exclusivity Period (other than with respect to Patent
Rights, for which the provisions of Article XII shall apply), granted to a
Party(ies) with respect to a Product in any country in the applicable Territory.

                  6.22 Non-Compete. [********************************], neither
Novartis nor Regeneron (nor their respective Affiliates or licensees) shall,
directly or indirectly, Commercialize any Competing Products in any part of the
Territory; provided, however, that:

                  (a)      a Trap-1 Product shall not be considered a Competing
Product (i) in any Co-Commercialization Country or Co-Marketing Country in the
Trap-1 Territory in which this Agreement has been terminated with respect to
Trap-1 (A) by Novartis pursuant to Sections 19.3 or 19.4 or (B) by Regeneron
pursuant to Sections 19.5, 19.6 or 19.7 or (ii) in any country outside the
Trap-1 Territory.

                  (b)      an IL-1 Antibody Product shall not be considered a
Competing Product in any country outside of the IL-1 Antibody Territory;

                  (c)      an IL-1 Antibody Product shall not be considered a
Competing Product in the event that Regeneron does not properly exercise the
IL-1 Antibody Opt-In Right;

                  (d)      an IL-1 Antibody Product shall not be considered a
Competing Product in any Co-Commercialization Country or Co-Marketing Country in
the IL-1 Antibody Territory in which this Agreement has been terminated with
respect to the IL-1 Antibody: (i) by Regeneron pursuant to Sections 19.3 or
19.4; or (ii) by Novartis pursuant to Sections 19.5, 19.6 or 19.7;

                  (e)      a Trap-2 Product shall not be considered a Competing
Product in the event that Novartis does not properly exercise the Trap-2 Opt-In
Right;

                  (f)      a Trap-2 Product shall not be considered a Competing
Product (i) in any Co-Commercialization Country or Co-Marketing Country in the
Trap-2 Territory in which this Agreement has been terminated with respect to
Trap-2 (A) by Novartis pursuant to Sections 19.3 or 19.4 or (B) by Regeneron
pursuant to Sections 19.5, 19.6 or 19.7 or (ii) in any country outside the
Trap-2 Territory;

                  (g)      the provisions of this Section 6.22 shall not survive
expiration of the Term of this Agreement pursuant to Section 19.2 (but shall
survive termination of this Agreement in whole or in part, except as set forth
in this Section 6.22); and

                                      -48-

<PAGE>

                  (h)      a Party shall not be considered in breach of this
Section 6.22 by reason of the acquisition by such Party of a Person if (i) the
activity of such Person which would cause such breach in absence of this Section
6.22(h) is not the primary business of such Person; (ii) prior to the closing of
such acquisition, the acquiring Party commits in writing to the other Party
that, promptly following the closing of such acquisition, it will divest itself
of the offending assets and/or activity; and (iii) the acquiring Party uses
Commercially Reasonable Efforts to pursue such divestiture, and in the event
that such divestiture is not completed within six (6) months of the closing of
such acquisition, the acquiring Party ceases all Commercialization of such
Competing Product.

                  6.23 Loan Facility for Shared Promotion Expenses.

                  (a)      General. Novartis shall create an internal loan
facility from which, subject to the further provisions hereof, it shall make
advances to Regeneron, and from which Regeneron may draw funds in U.S. Dollars
from time to time, in amounts that in the aggregate equal up to the share of
Shared Promotion Expenses incurred after 2005 and prior to the first Launch of a
Trap-1 Product in connection with the Co-Commercialization of any Trap-1 Product
for which Regeneron is responsible in accordance with the Agreement (the
"Eligible Regeneron Promotional Expenses"). Such loan facility is referred to
herein as the "Promotional Expense Facility", and such advances made thereunder
are referred to herein collectively as the "Promotional Expense Facility Loans".

                  (b)      Draws. To draw on the Promotional Expense Facility,
Regeneron shall submit a notice of funding (a "Promotional Expense Facility
Funding Notice") to Novartis, signed by its Chief Financial Officer, specifying
the amount of the requested advance (which shall not be less than $1 million per
request) and certifying that such amount is in respect of Eligible Regeneron
Promotional Expenses. Promotional Expense Facility Loans shall be made by
Novartis within twenty (20) Business Days after Novartis' receipt of a
Promotional Expense Facility Funding Notice.

                  (c)      Crediting of Promotional Expense Facility Loans; Cash
Disbursements. Immediately upon any Promotional Expense Facility Loan being
made, Regeneron hereby authorizes and directs Novartis to, and Novartis shall,
credit the amount of such Promotional Expense Facility Loan against Eligible
Regeneron Promotional Expenses, and each of Regeneron and Novartis acknowledges
and agrees that there will be no cash disbursements of any Promotional Expense,
Facility Loans to the extent they are so applied against Eligible Regeneron
Promotional Expenses; provided, however, that Novartis shall disburse to
Regeneron (as Regeneron may direct Novartis in a Promotional Expense, Facility
Funding Notice) all or a portion of any Promotional Expense Facility Loan to the
extent of Eligible Regeneron Promotional Expenses actually incurred by Regeneron
or its Affiliates. Any cash disbursement of a Promotional Expense Facility Loan
shall be made by Novartis by wire transfer of funds to an account specified by
Regeneron in the Promotional Expense Facility Funding Notice within the time
period provided in subparagraph (ii) above.

                  (d)      Interest. The principal balance of Promotional
Facility Loans outstanding shall bear interest from the date advanced at a rate
per annum equal to the LIBOR Rate, plus 2.5%, and shall be compounded quarterly
and, unless the Promotional Facility Loans have been accelerated in accordance
with paragraph (j) below, shall be payable as provided in paragraph (e) below.
Overdue principal and, to the extent permitted by law, overdue interest in
respect of each Promotional Facility Loan shall, in each case, bear interest at
a rate per annum equal to the rate which is 2% in excess of the rate borne by
such

                                      -49-

<PAGE>

Promotional Facility Loan. Interest which accrues under the immediately
preceding sentence shall be payable on demand.

                  (e)      Repayment. The full amount of all outstanding
Promotional Expense Facility Loans, and all accrued and unpaid interest thereon,
will be due and payable three (3) years after the earlier of (A) the first
Launch of a Trap-1 Product in the United States or Europe and (B) the effective
date of termination of the Agreement by Novartis with respect to the entire
Trap-1 Territory for all Trap-1 Products.

                  (f)      Prepayment. Regeneron shall have the right to prepay
any Promotional Expense Facility Loans prior to the time required in paragraph
(e) above, without premium or penalty (except as provided below in paragraph
(h)), in whole or in part, upon at least one Business Day's prior written notice
(or telephonic notice confirmed by in writing, which may be by email) to
Novartis of its intent to make such prepayment. The amount of any such
prepayment (or repayment, whether pursuant to paragraph (e), (j) or (k) shall be
applied pro rata against the principal amount of the then outstanding
Promotional Expense Facility Loans and accrued and unpaid interest thereon, in
the order of their dates of disbursement, with any prepayment being first
applied against the longest outstanding Promotional Expense Facility Loan.

                  (g)      Method of Repayment. Except as otherwise specifically
provided herein, all payments of principal or accrued interest on Promotional
Expense Facility Loans shall be made in U.S. Dollars in immediately available
funds to an account of Novartis specified by it to Regeneron, and shall be paid
net of withholding taxes, if applicable.

                  (h)      Breakage Cost. Regeneron shall compensate Novartis,
upon the written request of Novartis, for any expenses or costs (a reasonably
detailed calculation of which shall be provided by Novartis together with such
written request) incurred by Novartis as a result of any prepayment pursuant to
paragraph (f) of any one or more Promotional Expense Facility Loans having
occurred on a date other than the last date of a LIBOR Period relating to such
Promotional Expense Facility Loan or Promotional Expense Facility Loans.

                  (i)      Termination of Promotional Expense Facility. The
Promotional Expense Facility shall automatically terminate, and no further
Promotional Expense Facility Loans shall be advanced thereunder, upon the
earlier of (A) the effective date of termination of the Agreement by Novartis
with respect to the entire Trap-1 Territory for all Trap-1 Products and (B) the
acceleration of the date of payment of Promotional Expense Facility Loans
pursuant to subparagraph (x) below.

                  (j)      Acceleration of Promotional Expense Facility Loans.
Novartis may, by notice to Regeneron, declare all principal of, and accrued and
unpaid interest on, all Promotional Expense Facility Loans due and payable, if a
Post 2003/Promotional Expense Event of Default referred to in clause (A) or (B)
of subparagraph (x) of Section 5.9(b) shall have occurred (and in such event
upon such notice all such principal and unpaid interest shall immediately become
due and payable) or if a Post 2003/Promotional Expense Event of Default referred
to in clause (C) of subparagraph (x) of Section 5.9(b) shall have occurred (and
in such event upon such notice all such principal and interest shall be due and
payable upon the first anniversary of the date of such notice), and if a Post
2003/Promotional Expense Event of Default referred to in clause (D) of
subparagraph (x) of Section 5.9(b) shall have occurred, all such principal and
interest shall automatically become due and payable.

                                      -50-

<PAGE>

                  (k)      Right of Set-off. In addition to any rights now or
hereafter granted under applicable law or otherwise, and not by way of
limitation of any such rights, if any default by Regeneron in repaying when due
all principal of, and accrued and unpaid interest on, all outstanding
Promotional Expense Facility Loans has occurred and is continuing, Novartis may,
upon prior notice to Regeneron, set off against all such unpaid principal and
interest any amount payable by Novartis to Regeneron under the Agreement.

                  (l)      Survival. This Section 6.23 shall survive termination
of this Agreement.

                                   ARTICLE VII

                         CLINICAL AND REGULATORY AFFAIRS

                  7.1 Ownership of Approvals and Registration Filings.

                  (a)      Regeneron shall be the Lead Regulatory Party, and
shall own all Approvals and Registration Filings, with respect to the Trap-1
Product in the U.S. and the Trap-2 Product in the U.S. and shall have the rights
and obligations set forth in Sections 7.2 to 7.4 (inclusive) with respect
thereto; provided, however, that Novartis shall perform the regulatory tasks set
forth on SCHEDULE 11 with respect to the Trap-1 Product and the Trap-2 Product
in the U.S., or as otherwise deemed appropriate by the JOC, provided such tasks
are performed in accordance with this Agreement and applicable Law.

                  (b)      Novartis shall be the Lead Regulatory Party, and
shall own all Approvals and Registration Filings, with respect to: (i) the
Trap-1 Product in the Trap-1 Territory, other than in the U.S., with effect from
the Effective Date; (ii) the Trap-2 Product in the Trap-2 Territory, other than
in the U.S., with effect from the date of any proper exercise by Novartis of the
Trap-2 Opt-In Rights; and (iii) the IL-1 Antibody Product, throughout the IL-1
Antibody Territory, and, in each case, shall have the rights and obligations set
forth in Sections 7.2 to 7.4 (inclusive) with respect thereto.

                  (c)      The Lead Regulatory Party shall license, transfer,
provide a letter of reference with respect to, or take other action necessary to
make available the relevant Registration Filings and Approvals to and for the
benefit of the other Party.

                  7.2 Regulatory Coordination.

                  (a)      The Lead Regulatory Party shall oversee, monitor and
coordinate all regulatory actions, communications and filings with and
submissions, including supplements and amendments thereto, to, each applicable
Regulatory Authority with respect to the IL-1 Product in the jurisdiction as to
which it is the Lead Regulatory Party. The Lead Regulatory Party shall perform
all such activities in accordance with the Joint Steering Committee-approved
Consolidated Co-Development Plans and Consolidated Co-Commercialization Plans.

                  (b)      The Parties shall establish procedures to ensure that
the Parties exchange on a timely basis all necessary information to enable the
Lead Regulatory Party to comply with all regulatory obligations on a global
basis, including, without limitation, filing

                                      -51-

<PAGE>

updates or supplements with Regulatory Authorities, pharmacovigilance filings,
manufacturing supplements, and investigator notifications to Regulatory
Authorities. The Parties shall provide to each other prompt notice of any
Approval of an IL-1 Product.

                  (c)      Notwithstanding anything herein to the contrary, the
Parties shall work together cooperatively (i) in the preparation of proposed
product labeling and any negotiations with Regulatory Authorities regarding IL-1
Product labeling, (ii) in the preparation of regulatory strategies with respect
to all regulatory actions, communication, filings and submissions, including any
supplements and amendments to Registration Filings, (iii) to prepare for
Advisory Committee or any similar meeting concerning IL-1 Products, and (iv) in
the response to Regulatory Authorities to any of the communications or inquiries
referred to in Section 7.5(b)(i)-(vi). These regulatory matters shall be
conducted with the approval and guidance of the JOC, or the Joint Regulatory
Sub-Committee of the JOC, if any. The JOC (or Joint Regulatory Sub-Committee, if
any) shall oversee the implementation of a plan for the registration and
regulatory strategy for Registration Filings in the applicable Territory,
including the schedule for such filings and submissions. All material regulatory
decisions for the IL-1 Products shall be made through the JOC (or Joint
Regulatory Sub-Committee, if any).

                  7.3 Regulatory Meetings. The Lead Regulatory Party shall be
responsible for interfacing, corresponding and meeting with the applicable
Regulatory Authorities with respect to each IL-1 Product in the jurisdiction as
to which it is the Lead Regulatory Party. The Party which is not the Lead
Regulatory Party shall have the right to have representatives participate in all
material meetings and telephone discussions between representatives of the Lead
Regulatory Party and applicable Regulatory Authorities with respect to each IL-1
Product.

                  7.4 Regulatory Correspondence. The Lead Regulatory Party shall
promptly provide to the other Party copies of any material correspondence
received from or submitted to the applicable Regulatory Authorities pertaining
to each IL-1 Product (including, without limitation, any meeting minutes).

                  7.5 Assistance.

                  (a)      Each Party shall cooperate with the other Party to
provide all reasonable assistance and take all actions reasonably requested by
the other Party that are necessary or desirable to enable the other Party to
comply with any Law applicable to any IL-1 Product.

                  (b)      Such assistance and actions shall include, among
other things, keeping the other Party informed, commencing within twenty-four
(24) hours after notification of any action by, or notification or other
information which it receives (directly or indirectly) from, any Regulatory
Authority or other Governmental Authority, which (A) raises any material
concerns regarding the safety or efficacy of any IL-1 Product, (B) indicates or
suggests a potential material liability for either Party to Third Parties
arising in connection with any IL-1 Product, or (C) is reasonably likely to lead
to a recall or market withdrawal of any IL-1 Product. Information that shall be
disclosed pursuant to this Section 7.5(b) shall include, but not be limited to:

                  (i)      governmental or regulatory inspections of
         manufacturing, distribution or other related facilities used for any
         IL-1 Product;

                                      -52-

<PAGE>

                  (ii)     inquiries by Regulatory Authorities or other
         Governmental Authorities concerning clinical investigation activities
         (including inquiries of investigators, clinical research organizations
         and other related parties) relating to any IL-1 Product;

                  (iii)    any communication from Regulatory Authorities or
         other Governmental Authorities pertaining to the Manufacture, sale,
         promotion or distribution of any IL-1 Product;

                  (iv)     any other Regulatory Authority or other Governmental
         Authority reviews or inquiries relating to any IL-1 Product;

                  (v)      receipt of a warning letter relating to any IL-1
         Product; and

                  (vi)     an initiation of any Regulatory Authority or other
         Governmental Authority investigation, detention, seizure or injunction
         concerning any IL-1 Product.

                  7.6 Pharmacovigilance and Safety Data Exchange.

                  (a)      Each Party shall designate a qualified person
responsible for pharmacovigilance in the countries in which such Party owns an
Approval. Such qualified person shall be responsible for (A) the collection of
adverse event reports for the relevant IL-1 Product reported to its
corresponding Party and Affiliates thereof, (B) notification to the other Party
of such reports in accordance with paragraph (b) below, (C) the preparation and
timely submission of individual written reports to the relevant Regulatory
Authority in compliance with applicable Law, (D) the preparation and timely
submission of periodic safety update reports, (E) answering pharmacovigilance
questions, and (F) all notifications and communications with the appropriate
Regulatory Authorities relating to pharmacovigilance; provided, however, that as
set forth on SCHEDULE 11, Novartis shall coordinate pharmaco-vigilance
activities and submission of reports for each IL-1 Product in the applicable
Territory.

                  (b)      Each Party shall promptly notify the other Party of
all material information coming into its possession during the applicable Term
concerning side effects, injury, toxicity or sensitivity reactions, including
non-trivial unexpected increased incidence and severity thereof, associated with
commercial or clinical uses, studies, investigations or tests with IL-1 Products
(animal or human), throughout the world, whether or not determined to be
attributable to an IL-1 Product ("Adverse Reaction Reports"). Each Party and its
Affiliates shall assist the other Party and its Affiliates by promptly obtaining
any follow-up information to the initial report from the reporter as reasonably
requested by the other Party or its Affiliate. Without limitation to the
foregoing, the Parties shall follow the specific procedures to coordinate the
timing and handling of Adverse Event Reaction Reports to be set forth in
SCHEDULE 12, to ensure prompt communications of such notifications and
compliance with reporting obligations to Regulatory Authorities.

                                  ARTICLE VIII

                            MANUFACTURING AND SUPPLY

                  8.1 Supply of Clinical Supply Requirements for Trap-1 Product.
Regeneron shall use Commercially Reasonable Efforts to provide an adequate and
timely supply of properly forecast Clinical Supply Requirements of the Trap-1
Product in the Territory

                                      -53-

<PAGE>

through the earlier of the date of the first Launch of a Trap-1 Product or the
date that Novartis is capable of producing such Clinical Supply Requirements
following the technology transfer referred to in Section 8.2(a). Regeneron shall
supply such Clinical Supply Requirements of the Trap-1 Product at Regeneron's
Clinical Supply Cost for such product.

                  8.2 Supply of Commercial Requirements for Trap-1 Product.

                  (a)      Novartis shall use Commercially Reasonable Efforts to
provide an adequate and timely supply of properly forecast Commercial
Requirements of the Trap-1 Product in the Territory during the applicable Term
of this Agreement. Novartis shall also use Commercially Reasonable Efforts to
provide an adequate supply of properly forecast Clinical Supply Requirements of
the Trap-1 Product post first Launch in the Territory during the applicable Term
of this Agreement at Novartis' Clinical Supply Cost for such product. For
purposes of calculating the Target Profit Splits, Commercial Requirements of the
Trap-1 Product shall be provided [*****************************************]:

                  (i)      [**********************************];

                  (ii)     [*********************************];

                  (iii)    [******************************]; and

                  (iv)     [****************************];

SCHEDULE 7 hereto sets forth a non-binding example of the cost pricing details
for the processing of the Trap-1 using the above-referenced principles. The
Parties agree that the Trap-1 cost pricing details set forth in SCHEDULE 7 are
for illustrative purposes only and are not binding upon Novartis and have no
legal effect whatsoever.

         If the Trap I Phase IIB Clinical Trial that is ongoing as of the
Effective Date achieves the Trial Success Criteria, Novartis shall use
Commercially Reasonable Efforts to constitute, equip, validate and license a
manufacturing facility for the production of Trap-1, subject however to
successful technology transfer with respect to the Trap-1 Product. Novartis
shall use Commercially Reasonable Efforts to ensure that such production
facility [**************************]. Novartis shall use Commercially
Reasonable Efforts to ensure that such production facility shall
[*****************************].

                  (b)      Novartis shall be responsible for manufacturing
Trap-1 Product in accordance with all applicable laws, including applicable Good
Manufacturing Practices. Promptly following the execution of this Agreement, the
Parties will enter into a separate Quality Agreement which shall specify certain
additional responsibilities between the Parties. The Quality Agreement, which
shall constitute an Ancillary Agreement for purposes hereof, shall be
substantially in the form annexed hereto as Exhibit A, with such changes as are
mutually agreed upon by the Parties.

                  (c)      Novartis shall notify Regeneron if it reasonably
determines that it will not be able to supply, on a long term basis, the agreed
upon demand forecast for the Trap-1 Product. Upon such notification and in order
to avoid and mitigate a Stock-Out Event, the matter shall be referred to the JOC
to determine what, if any alternative supply source of Trap-1 Product (an
"Alternative Supplier) should be identified and established. The goal of the
Parties in identifying an Alternative Supplier will be first to use the internal
capacity of

                                      -54-

<PAGE>

Novartis and/or its Affiliates and/or Regeneron to fill the supply shortfall. In
the event the JOC agrees to establish an Alternative Supplier, each Party shall
transfer or license (on a royalty free basis) Know-How and Patent Rights
necessary to transfer production to such Alternative Supplier in a timely manner
and provide reasonable assistance to the Alternative Supplier to effect such
transfer. Any increase in the Cost of Goods Sold and any other reasonable and
direct costs directly associated with the transfer of production
responsibilities to the Alternative Supplier shall be borne exclusively by
Novartis.

                  (d)      Novartis (or its local Affiliate) shall be
responsible for the distribution of the Trap-1 Product in the
Co-Commercialization Countries. Novartis will maintain and manage Trap-1 Product
inventory levels based on its internal risk assessment and inventory management
policy. Other than in the event of a Force Majeure, if Novartis fails to
manufacture and maintain sufficient Trap-1 Product after Launch and such action
results in Novartis and its Affiliates having [*************************] (a
"Stock-Out Event"), then Novartis agrees to the following reduction in COGS
within the Net Sales determination for purposes of calculating Target Profit
Splits:

                  (i)      [*****************************************];

                  (ii)     [****************************************]; and

                  (iii)    [*****************************************].

                  (e)      The Parties will agree upon the Trap-1 manufacturing
design and build-out time line to ensure adequate quantities of the Trap-1 are
available at or prior to Launch, in the Technology Transfer Agreement.

                  (f)      In the event of a Co-Marketing, the Parties will
negotiate in good faith a separate supply agreement providing for the supply of
Trap-1 Product at the agreed upon price and containing terms and provisions
customary for that type of agreement in the pharmaceutical industry as deemed
necessary and/or required and/or advisable by the Parties.

                  8.3 Supply of Clinical Supply Requirements and Commercial
Requirements for IL-1 Antibody Product. Novartis shall use Commercially
Reasonable Efforts to provide an adequate supply of properly forecast Clinical
Supply Requirements and Commercial Requirements of the IL-1 Antibody Product in
the IL-1 Antibody Territory during the applicable Term of this Agreement.
Novartis shall supply such Clinical Supply Requirements of the IL-1 Antibody
Product at Novartis' Clinical Supply Cost for such product. Commercial
Requirements of the IL-1 Antibody Product shall be provided at a price to be
determined in accordance with the pricing parameters referenced in Section 8.2
above and SCHEDULE 7 for the Trap-1 Product. In the event of a Co-Marketing, the
Parties will negotiate in good faith a separate supply agreement providing for
the supply of product at the agreed upon price containing terms and provisions
customary for that type of agreement in the pharmaceutical industry as deemed
necessary and/or required and/or advisable by the Parties for the IL-1 Antibody
Product.

                  8.4 Supply of Clinical Supply Requirements and Commercial
Requirements for Trap-2 Product. Novartis shall use Commercially Reasonable
Efforts to provide an adequate supply of properly forecast Clinical Supply
Requirements (post Phase II Clinical Trials) and Commercial Requirements of the
Trap-2 Product in the Trap-2 Territory during the applicable Term of this
Agreement. Clinical Supply Requirements of the Trap-2 Product

                                      -55-

<PAGE>

shall be provided at Novartis' Clinical Supply Cost for such product. Commercial
Requirements of the Trap-2 Product shall be provided at a price to be determined
in accordance with the pricing parameters as referenced in Section 8.2 above and
SCHEDULE 7 for the Trap-1 Product. In the event of a Co-Marketing, the Parties
will negotiate in good faith a separate supply agreement providing for the
supply of product at the agreed upon price containing terms and provisions
customary for that type of agreement in the pharmaceutical industry as deemed
necessary and/or required and/or advisable by the Parties for the Trap-2
Product.

                                   ARTICLE IX

                           PERIODIC REPORTS; PAYMENTS

                  9.1 Periodic Reports. During the applicable Term, Novartis and
Regeneron shall each prepare and deliver to the other Party and to the JOC the
periodic reports specified below in this Section 9.1:

                  (a)      Each Party shall deliver electronically the reports
required to be delivered by it pursuant to Sections 5.8 and 6.6;

                  (b)      Novartis shall deliver electronically to Regeneron a
monthly detailed Net Sales report with monthly and year-to-date sales for each
IL-1 Product by country in local currency and U.S. Dollars;

                  (c)      Within thirty (30) days following the end of each
calendar quarter, Novartis shall deliver electronically a written report setting
forth: (i) the Net Sales of each IL-1 Product for that quarter, by dosage form
and unit size, including the average sales price of each such IL-1 Product and
an accounting of the deductions from Net Sales permitted by the definition
thereof; and (ii) adjustments (including reimbursements or recoupment of prior
deductions), if any, to Net Sales reported for any previous calendar quarter;

                  (d)      Within thirty (30) days following the end of each
calendar quarter, each Party that has incurred any Development Costs in that
calendar quarter shall deliver electronically a written report setting forth the
Development Costs incurred by such Party in such calendar quarter;

                  (e)      Within thirty (30) days following the end of each
calendar quarter following Launch in any Co-Commercialization Country, each
Party (through their local Affiliates where appropriate) shall each deliver
electronically to the other Party (or its local Affiliate) and to the JOC a
quarterly Country Co-Commercialization Report for such Co-Commercialization
Country. In addition, each Party (through their respective local Affiliates
where appropriate) shall keep the JOC informed regarding the activities of its
(or its local Affiliate's) Qualified Sales Representatives in Co-Promoting each
IL-1 Product in each Co-Promotion Country and Co-Branding Country, including
information relating to market developments, acceptance of such IL-1 Product,
complaints concerning such IL-1 Product and similar information; and

                  (f)      Within sixty (60) days following the end of each
calendar quarter, Novartis shall deliver electronically to Regeneron a
Consolidated Net Sales and Expense Report in respect of such calendar quarter,
combining the information reported by each Party and showing its calculations of
the amount of any payments to be made by the Parties

                                      -56-

<PAGE>

hereunder for such quarterly period as contemplated by Section 9.2 and, if
applicable, providing for the netting of such payments.

                  Such reports shall be in such form, format and level of
detail as may be approved by the JOC.

                  9.2 Funds Flow.

                  (a)      Target Profit Split. The Parties shall agree, through
the Finance Sub-Committee, on appropriate payments to achieve the applicable
Target Profit Split and sharing of costs and expenses based on the principles
set forth below:

                  (i)      Each Party is entitled to be reimbursed for expenses
         incurred in accordance with the Consolidated Co-Development Plan and
         the Consolidated Co-Development Budget, the Country
         Co-Commercialization Plans and the Country Co-Commercialization
         Budgets, and the Consolidated Co-Commercialization Plans and
         Consolidated Co-Commercialization Budgets.

                  (ii)     Development Costs shall be shared as described in
         SCHEDULE 4;

                  (iii)    Detailing efforts, reimbursements and payments shall
         be in accordance with Section 6.10;

                  (iv)     Net profit sharing will be calculated based on Net
         Sales minus COGS and Shared Promotional Expenses and shall be
         determined according to the Target Profit Split as described in
         SCHEDULE 1.

                  (b)      Mechanism For Achieving Target Profit Split. The
Parties shall agree, through the Finance Sub-Committee, on an appropriate
mechanism to achieve the Target Profit Split based on the principles set forth
in Section 9.2(a) above. Such mechanism shall be based on the principles set
forth below:

                  (i)      at the local level, for Co-Commercialization
         Countries in which both Parties are operating, expenses and profit
         sharing shall be calculated and executed between local affiliates in
         local currency;

                  (ii)     a virtual consolidated profit and loss statement, by
         Region, will be calculated in U.S. Dollars to determine each Party's
         share of total consolidated expenses and profits in the Territory;

                  (iii)    final settlements/funds flows shall incorporate any
         amounts already shared at the local levels (converted into U.S.
         Dollars); and

                  (iv)     the Finance Sub-Committee shall be responsible for
         developing and proposing adequate policies, procedures, templates and
         timelines for the implementation of Target Profit Splits and funds flow
         calculations and mechanics.

                  9.3 Royalty. If Regeneron has properly exercised the IL-1
Antibody Opt-In Rights, then with respect to Annual Net Sales of any IL-1
Antibody Product in Europe and in accordance with the terms and conditions set
forth in SCHEDULE 3 hereto, Novartis shall pay to Regeneron the applicable
royalty as set forth in SCHEDULE 3.

                                      -57-

<PAGE>

                  9.4 Upfront Payments and Milestone Payments.

                  (a)      In addition to the payments contemplated in Sections
9.2 and 9.3, in consideration of future Development activities to be conducted
for the United States with respect to IL-1 Products, NPC shall pay to Regeneron,
within three (3) Business Days of the Effective Date, an amount of US $27
million.

                  (b)      In addition to the payments contemplated in Sections
9.2 and 9.3 above, in consideration of the rights granted by each Party to the
other hereunder, each Party shall pay to the other amounts set forth in SCHEDULE
6 upon the occurrence of the corresponding event.

                  9.5 Revenue and Expenses in Co-Marketing Countries. Each Party
shall retain all revenues accrued by such Party (or its relevant local
Affiliate) on its sales of any IL-1 Product in each Co-Marketing Country. Each
Party shall be responsible for its own costs and expenses incurred with respect
to any IL-1 Product in each Co-Marketing Country. Within thirty (30) days
following the end of each calendar quarter following Launch in any Co-Marketing
Country, each Party shall provide the JOC with a detailed report of Net Sales
made by the Party or its local Affiliates in Co-Marketing Countries. The format
and timing of such reports shall be as approved by the JOC.

                  9.6 Allocation of Costs and Expenses. As soon as practicable
after the Effective Date, the Parties will agree on a method for allocating
cross-region Development Costs and Shared Promotion Expenses.

                  9.7 Invoices and Documentation. The JOC shall approve the form
of any necessary documentation relating to any payments hereunder so as to
afford the Parties appropriate accounting treatment in relation to any of the
transactions or payments contemplated hereunder, which documentation may
include, without limitation, invoices, bills of account, work orders and
purchase orders.

                  9.8 Payment Currency. All amounts due under this Agreement and
any Ancillary Agreement shall be paid to the designated Party in the currency
designated for that purpose by the JOC, or, in the event that no such
designation has been approved by the JOC, in United States Dollars (except in
the case of any payments to be made between local Affiliates of Regeneron and
Novartis operating in the same Co-Commercialization Country as each other, which
payments may be made in the local currency common to such Affiliates); provided
that in such event payments reflecting compensation payments in particular
Co-Commercialization Countries shall be netted against local
Co-Commercialization expenses, to the extent possible, so as to minimize the
amount to be paid in United States Dollars. In those cases where the amount due
in United States Dollars is calculated based upon one or more currencies other
than United States Dollars, such amount due shall be determined on the basis of
Novartis' account of sales which represents the conversion of all local currency
sales year-to-date to United States Dollars at a sales weighted average exchange
rate for the year-to-date in which the sales are recorded.

                  9.9 Late Payments. The Parties agree that, unless otherwise
mutually agreed by the Parties or otherwise provided in this Agreement, amounts
due by one Party to the other shall be payable to a bank account, details of
which are to be communicated by the receiving Party. Unless otherwise mutually
agreed by the Parties or otherwise provided in this Agreement, all payments
under this Agreement shall earn interest from the date due until paid

                                      -58-

<PAGE>

at a rate equal to the sum of (i) the prime rate of interest declared from time
to time by Citibank, N.A. in New York, New York, plus (ii) two percent (2%) per
annum (such sum being referred to as the "Default Interest Rate").

                  9.10 Taxes. Any withholding or other taxes that either Party
or its Affiliates are required by Law to withhold or pay on behalf of the other
Party, with respect to any payments to such other Party hereunder, shall be
deducted from such payments and paid contemporaneously with the remittance to
the other Party; provided, however, that the withholding Party shall furnish the
other Party with proper evidence of the taxes so paid. Each Party shall furnish
the other Party with appropriate documents to secure application of the most
favorable rate of withholding tax under applicable Law.

                                   ARTICLE X

                               DISPUTE RESOLUTION

                  10.1 Resolution of Disputes.

                  (a)      Generally. Subject to Section 10.2(f) and Section
16.2, the Parties agree that no dispute, controversy or claim arising out of or
in connection with this Agreement (or any Ancillary Agreement) or the Parties'
activities hereunder (or thereunder) shall be resolved other than pursuant to
Article III or Article X of this Agreement, and the Parties further agree that,
subject to Section 10.2(f) and Section 16.2, in no event shall any such dispute,
controversy or claim be the subject of private litigation between the Parties.

                  (b)      Governance Disputes. Disputes, controversies and
claims related to matters intended to be decided within the governance
provisions of this Agreement set forth in Article III shall be resolved pursuant
to Article III, except to the extent such dispute, controversy or claim
constitutes a Legal Dispute, in which event the provisions of Sections 10.1(c)
and 10.2 shall apply.

                  (c)      Legal Disputes. The Parties agree that, subject to
Sections 16.2 and 10.2(f), they shall use Commercially Reasonable Efforts,
through their participation in the JSC in the first instance, to resolve any
Legal Dispute arising after the commencement of the Term by good faith
negotiation and discussion. In the event that the JSC is unable to resolve any
such Legal Dispute within fifteen (15) days after such Legal Dispute is
submitted to it, either Party may submit the Legal Dispute to the Executive
Officers for resolution. In the event the Executive Officers are unable to
resolve any such Legal Dispute within thirty (30) days after such Legal Dispute
is submitted to them for resolution, the Parties shall be free to resort to
arbitration pursuant to Section 10.2.

                  10.2 Arbitration of Legal Disputes.

                  (a)      Subject to Section 10.1(b), in the event that the
Parties are unable to resolve any Legal Dispute through the procedures described
in Section 10.1(c) above, the Legal Dispute shall, at the request of either
Party and subject to Sections 16.2 and 10.2(f), be finally settled by
arbitration in accordance with the Rules of International Arbitration (the
"Rules") of the International Chamber of Commerce as presently in force.

                  (b)      The arbitration panel shall consist of three (3)
arbitrators, each of whom must have legal or business experience in
pharmaceutical licensing matters and/or

                                      -59-

<PAGE>

pharmaceutical marketing matters, as appropriate. The arbitrators are to be
selected as follows: Novartis shall nominate one such qualified arbitrator;
Regeneron shall nominate one such qualified arbitrator; and the two arbitrators
so nominated shall nominate a third such qualified arbitrator, who shall be the
presiding arbitrator, in each case subject to confirmation by the International
Court of Arbitration of the International Chamber of Commerce in Paris, France
(the "ICC Court"). In the event either Novartis or Regeneron shall have failed
to nominate a qualified arbitrator as provided above within fifteen (15)
Business Days after the other Party shall have nominated its arbitrator, or the
two arbitrators so nominated shall fail to agree on a third arbitrator as
provided above within fifteen (15) days after the appointment of the second
arbitrator, the second arbitrator and/or the presiding arbitrator, as the case
may be, shall be appointed by the ICC Court.

                  (c)      The place of arbitration shall be New York, New York,
and the language of the arbitration shall be English.

                  (d)      Except as otherwise provided in this Agreement, the
arbitration procedure set forth in this Section 10.2 shall be the sole and
exclusive means of settling or resolving any Legal Dispute.

                  (e)      Within thirty (30) days after the third and presiding
arbitrator has been confirmed by the ICC Court, the Parties shall exchange all
documents in their respective possession that are relevant to the issues in
dispute and not protected from disclosure by attorney-client privilege or other
immunity. Each Party shall also be permitted to take sworn oral deposition of
individuals, such depositions to be scheduled by mutual agreement and concluded
within thirty (30) days after the exchange of documents described above. At
least twenty (20) days prior to the first scheduled hearing date, the Parties
shall identify the witnesses that they intend to present at the arbitration
hearing and the documentation on which they intend to rely. The Parties shall
use their Commercially Reasonable Efforts to conclude the arbitration hearings
within six (6) months following the confirmation of the third and presiding
arbitrator. The arbitrators shall issue their decision (including grounds and
reasoning) in writing no later than sixty (60) days following the conclusion of
the last arbitration hearing.

                  (f)      The arbitrators shall have the power to rule on
dispositive motions, including motions for summary judgment. By agreeing to
arbitration, the Parties do not intend to deprive any court of competent
jurisdiction of its jurisdiction to issue a pre-arbitral injunction or order for
specific performance, pre-arbitral attachment or other order in aid of
arbitration proceedings, and the Parties hereby consent to the jurisdiction of
any such court for such purposes. Without prejudice to such provisional remedies
as may be available under the jurisdiction of a national court, the arbitral
tribunal shall have full authority to grant provisional remedies or to order the
Parties to request that a court modify or vacate any temporary or preliminary
relief issued by a such court, and to award damages for the failure of any party
to respect the arbitral tribunal's orders to that effect. The award of the
arbitrators shall be final and binding on the Parties and may be presented by
either of the Parties for enforcement in any court of competent jurisdiction,
and the Parties hereby consent to the jurisdiction of such court solely for
purposes of enforcement of this arbitration agreement and any order or award
entered in an arbitration pursuant hereto.

                  (g)      The fees of the arbitrators and the other costs of
such arbitration, excluding attorneys' fees which each Party shall bear, shall
be borne and paid as the arbitrators determine.

                                      -60-

<PAGE>

                  (h)      Provided the Agreement has not terminated, the
Parties covenant to continue the performance under the Agreement in accordance
with the terms thereof, pending the final resolution of the Legal Dispute.

                                   ARTICLE XI

                         TRADEMARKS AND CORPORATE LOGOS

                  11.1 Corporate Logos. Each Party and its Affiliates shall
retain all right, title and interest in and to their respective corporate names
and logos.

                  11.2 Selection of Product Trademarks. The JOC shall select,
for approval by the JSC, one or more Product Trademarks (including back-up
trademarks) for each IL-1 Product for use with respect to such IL-1 Product
throughout the applicable Territory, it being agreed that for each IL-1 Product,
the Parties will endeavor to select a single Product Trademark to be used
throughout the applicable Territory (and in the case of the IL-1 Antibody
Product, throughout the world); provided, however, that the Parties may, where
appropriate, agree through the JSC to use different Product Trademarks for
different indications of a particular IL-1 Product. Each IL-1 Product shall be
promoted and sold in the Co-Promotion Countries and Co-Branding Countries under
the applicable Product Trademark(s) approved by the JSC. Novartis shall have the
first right to select one Product Trademark for use in each Co-Marketing Country
for each IL-1 Product and Regeneron shall have the second right to select one
Product Trademark for use in each Co-Marketing Country for each IL-1 Product.
Any additional Product Trademarks shall be fairly allocated between Novartis and
Regeneron for use in Co-Marketing Countries.

                  11.3 Ownership of Product Trademarks. Unless otherwise
mutually agreed between the Parties, Regeneron (or its local Affiliates, as
appropriate) shall own and retain all rights to Product Trademark(s) for the
Trap-1 Product and the Trap-2 Product, together with all associated domain
names, trade dress, service marks, copyrights and goodwill for the Trap-1
Product and the Trap-2 Product throughout the applicable Territory, other than
in the Co-Marketing Countries. Novartis (or its local Affiliates, as
appropriate) shall own and retain all rights to Product Trademark(s) for the
IL-1 Antibody Product, together with all associated domain names, trade dress,
service marks, copyrights and goodwill for the IL-1 Antibody Product throughout
the applicable Territory, other than in the Co-Marketing Countries. In the
Co-Marketing Countries, each Party shall own and retain all rights to Product
Trademark(s) selected by it (as set forth in Section 11.2 above), together with
all associated domain names, trade dress, service marks, copyrights and goodwill
in the Co-Marketing Countries.

                  11.4 Prosecution, Maintenance and Enforcement of Product
Trademarks. Regeneron will, at its own cost and expense, use Commercially
Reasonable Efforts to prosecute and maintain the Product Trademark for the
Trap-1 Product and the Trap-2 Product in the Co-Commercialization Countries of
the applicable Territory for the applicable Term. Novartis will, at its own cost
and expense, use Commercially Reasonable Efforts to prosecute and maintain the
Product Trademark for the IL-1 Antibody Product in the Co-Commercialization
Countries of the applicable Territory for the applicable Term. Notwithstanding
the foregoing, in the event either Party elects not to prosecute or maintain any
Product Trademark in a Co-Commercialization Country, the other Party shall have
the right to do so at its sole cost and expense, subject to consultation and
cooperation with the other Party.

                                      -61-

<PAGE>

                  11.5 License to the Trap-1 and Trap-2 Product Trademarks.
Regeneron hereby grants to Novartis a license to use the Product Trademark(s)
for the Trap-1 Product and the Trap-2 Product in the Co-Commercialization
Countries of the applicable Territory for the purposes of Novartis'
Co-Commercialization activities pursuant to this Agreement and subject to the
terms and conditions of this Agreement. Novartis' rights under this Section 11.5
may be sublicensed, but only to Novartis' Affiliates for the purposes of, and
subject to the terms and conditions of, this Agreement. Novartis and its
Affiliates shall have no rights in or to the Product Trademark for the Trap-1
Product or the Trap-2 Product or the goodwill pertaining thereto. Regeneron (and
its Affiliates, as appropriate) shall own and retain all rights in and to
trademark, trade dress, service marks, copyrights, and goodwill associated
therewith, and all use of the Product Trademark for the Trap-1 Product and the
Trap-2 Product by Novartis and its Affiliates shall, at all times inure to the
benefit of Regeneron. Novartis and its Affiliates shall utilize the Product
Trademark for the Trap-1 Product and the Trap-2 Product only on approved
Promotional Materials or other approved product-related materials for the Trap-1
Product and the Trap-2 Product for the purposes contemplated herein. Novartis
agrees that at no time during the applicable Term or thereafter, will it or any
of its Affiliates attempt to use or register any trademarks, trade dress,
service marks, trade names or domain names confusingly similar to the Product
Trademark(s) for the Trap-1 Product and Trap-2 Product or take any other action
which damages or dilutes the rights to, or goodwill associated with, such
Product Trademarks in the applicable Co-Commercialization Countries. Subject to
Article XIX, Novartis agrees that upon termination or expiration of the Term for
the Trap-1 Product or the Trap-2 Product (as applicable), Novartis and its
Affiliates will discontinue forthwith all use of the applicable Product
Trademark. All uses by Novartis of the Product Trademark for the Trap-1 Product
and the Trap-2 Product shall comply with the applicable local Law. Upon request
by Regeneron, Novartis shall (or shall cause its Affiliates, as appropriate, to)
execute such documents as may reasonably be required by Regeneron for the
purpose of recording the license, or assigning any rights in the trademark,
trade dress, service marks, copyrights and set forth in this Section 11.5 above
with any Governmental Authority.

                  11.6 License to the IL-1 Antibody Product Trademark. Novartis
hereby grants to Regeneron a license to use the Product Trademark(s) for the
IL-1 Antibody Product in the Co-Commercialization Countries of the applicable
Territory for the purposes of Regeneron's Co-Commercialization activities
pursuant to this Agreement and subject to the terms and conditions of this
Agreement. Regeneron's rights under this Section 11.6 may be sublicensed, but
only to Regeneron's Affiliates for the purposes of, and subject to the terms and
conditions of, this Agreement. Regeneron and its Affiliates shall have no rights
in or to the Product Trademark for the IL-1 Antibody Product or the goodwill
pertaining thereto. Novartis (and its Affiliates, as appropriate) shall own and
retain all rights in and to trademark, trade dress, service marks, copyrights,
and goodwill associated therewith, and all use of the Product Trademark for the
IL-1 Antibody Product by Regeneron and its Affiliates shall, at all times inure
to the benefit of Novartis. Regeneron and its Affiliates shall utilize the
Product Trademark for the IL-1 Antibody Product only on approved Promotional
Materials or other approved product-related materials for the IL-1 Antibody
Product for the purposes contemplated herein. Regeneron agrees that at no time
during the applicable Term or thereafter, will it or any of its Affiliates
attempt to use or register any trademarks, trade dress, service marks, trade
names or domain names confusingly similar to the Product Trademark(s) for the
IL-1 Antibody Product or take any other action which damages or dilutes the
rights to, or goodwill associated with, such Product Trademark(s) in the
applicable Co-Commercialization Countries. Subject to Article XIX, Regeneron
agrees that upon

                                      -62-

<PAGE>

termination or expiration of the Term for the IL-1 Antibody Product, Regeneron
and its Affiliates will discontinue forthwith all use of the Product Trademark.
All uses by Regeneron of the Product Trademark for the IL-1 Antibody Product
shall comply with the applicable local Law. Upon request by Novartis, Regeneron
shall (or shall cause its Affiliates, as appropriate, to) execute such documents
as may reasonably be required by Novartis for the purpose of recording the
license, or assigning any rights in the trademark, trade dress, service marks,
copyrights and set forth in this Section 11.6 above with any Governmental
Authority.

                  11.7 Use of Corporate Names. Each Party (through its
Affiliates, as appropriate) shall use Commercially Reasonable Efforts to include
the other Party's name (or such other Party's local Affiliate's name) with equal
prominence on materials related to each IL-1 Product (including, without
limitation, package inserts, packaging, trade packaging, samples, and all
Promotional Materials used or distributed in connection with the applicable IL-1
Product) in the Co-Commercialization Countries in the applicable Territory,
unless to do so would be prohibited under applicable Laws. Accordingly, each
Party grants to the other (and its Affiliates) the right, free of charge, to use
its name and logo on package inserts, packaging, trade packaging, samples and on
all Promotional Materials used or distributed in connection with the applicable
IL-1 Product in the Co-Commercialization Countries in the applicable Territory
during the applicable Term and thereafter for a period of one (1) year with
respect to advertising and Promotional Materials, and for a period of two (2)
years with respect to package inserts, packaging, labeling, trade packaging,
samples, or until the existing inventory of such IL-1 Product and Promotional
Materials is exhausted, whichever is earlier.

                                  ARTICLE XII

                            NEWLY CREATED INVENTIONS

                  12.1 Ownership of Newly Created Intellectual Property.

                  (a)      Sole Inventions. Each Party shall exclusively own all
intellectual property (including, without limitation, data, discoveries,
technical information, Know-How, patents, patent applications, proprietary
information, trade secrets and inventions) invented or generated solely by such
Party, its employees, agents and consultants ("Sole Inventions"). Sole
Inventions made solely by Novartis, its employees, agents and consultants are
referred to herein as "Novartis Sole Inventions." Sole Inventions made solely by
Regeneron, its employees, agents and consultants are referred to herein as
"Regeneron Sole Inventions."

                  (b)      Joint Inventions. The Parties shall jointly own all
intellectual property (including, without limitation, data, discoveries,
technical information, Know-How, patents, patent applications, proprietary
information, trade secrets and inventions) invented or generated jointly by an
individual or individuals having an obligation to assign such intellectual
property to Novartis, on the one hand, and an individual or individuals having
an obligation to assign such intellectual property to Regeneron, on the other
hand, on the basis of each Party having an undivided interest in the whole
("Joint Inventions").

                  (c)      Inventorship. Notwithstanding the above, for purposes
of determining whether a patentable invention is a Novartis Sole Invention, a
Regeneron Sole Invention or a Joint Invention, questions of inventorship shall
be resolved in accordance with United States patent laws, and, for purposes of
determining whether a copyrighted work is a Novartis Sole Invention, a Regeneron
Sole Invention or a Joint Invention, questions of copyright authorship

                                      -63-

<PAGE>

shall be resolved in accordance with United States copyright laws, provided,
further, that nothing in this Article XII shall relieve a Party or its
Affiliates of their obligations under Article XVI with respect to confidential
Company Information provided by the other Party or such other Party's
Affiliates.

                  12.2 Prosecution and Maintenance of Patent Rights.

                  (a)      Regeneron Solely-Owned Patent Rights. Regeneron shall
use Commercially Reasonable Efforts to prepare, file, prosecute and maintain, at
its own cost and expense, Patents and Patent Applications (as applicable) within
the Regeneron Patent Rights throughout the applicable Territory, and shall
confer with and keep Novartis reasonably informed regarding the status of such
activities. Regeneron shall have the exclusive right and option, at its own cost
and expense, to file and prosecute any Patent Applications covering Regeneron
Sole Inventions, and to maintain any Patents issuing thereon. Notwithstanding
the foregoing, if Regeneron elects not to prosecute or maintain any Regeneron
Patent Right, Novartis will have the right to do so at Novartis' sole cost and
expense, and Regeneron will assign such Patent Rights to Novartis.

                  (b)      Novartis Solely-Owned Patent Rights. Novartis shall
use Commercially Reasonable Efforts to prepare, file, prosecute and maintain, at
its own cost and expense, Patents and Patent Applications (as applicable) within
the Novartis Patent Rights throughout the applicable Territory, and shall confer
with and keep Regeneron reasonably informed regarding the status of such
activities. Novartis shall have the exclusive right and option, at its own cost
and expense, to file and prosecute any Patent Applications covering Novartis
Sole Inventions, and to maintain any Patents issuing thereon. Notwithstanding
the foregoing, if Novartis elects not to prosecute or maintain any Novartis
Patent Right, Regeneron will have the right to do so at Regeneron's sole cost
and expense, and Novartis will assign such Patent Rights to Regeneron.

                  (c)      Joint Patent Rights. With respect to any Joint Patent
Rights, the Parties shall consult with each other regarding the filing,
prosecution and maintenance of any Patents and Patent Applications, and
responsibility for such activities shall be the obligation of the Controlling
Party. The Controlling Party shall undertake such filings, prosecutions and
maintenance in the names of both Parties as co-owners. The Controlling Party
shall have the following obligations with respect to the filing, prosecution and
maintenance of Patent Applications and Patents on any such Joint Patent Rights:
(i) the Controlling Party shall permit the non-Controlling Party to review and
comment at least two (2) weeks prior to the filing of any priority Patent
Application by the Controlling Party; (ii) the Controlling Party shall notify
the non-Controlling Party within thirty (30) days after the filing of a Patent
Application by the Controlling Party; (iii) the Controlling Party shall notify
the non-Controlling Party within eight (8) months from the filing of the
priority Patent Application whether and in which countries it intends to file
convention Patent Applications; (iv) the Controlling Party shall provide the
non-Controlling Party promptly with copies of all communications received from
or filed in patent offices with respect to such filings; and (v) the Controlling
Party shall provide the non-Controlling Party, a reasonable time prior to taking
or failing to take action that would affect the scope or validity of rights
under any Patent Applications or Patents (including but not limited to
substantially narrowing or canceling any claim without reserving the right to
file a continuing or divisional Patent Application, abandoning any Patent or not
filing or perfecting the filing of any Patent Application in any country), with
notice of such proposed action or inaction so that the non-Controlling Party has
a reasonable opportunity to review and make comments, and take such

                                      -64-

<PAGE>

actions as may be appropriate in the circumstances. In the event that the
Controlling Party materially breaches the foregoing obligations and such breach
is not cured within thirty (30) days of a written notice from the
non-Controlling Party to the Controlling Party describing such breach, or in the
event that the Controlling Party fails to undertake the filing of a Patent
Application within ninety (90) days of a written request by the non-Controlling
Party to do so, the non-Controlling Party may assume the Controlling Party's
responsibility for filing, prosecution and maintenance of any such Joint Patent
Right, and will thereafter be deemed the Controlling Party for purposes hereof.
Notwithstanding the foregoing, the Controlling Party may withdraw from or
abandon any Patent or Patent Application relating to any Joint Patent Rights on
thirty (30) days' prior notice to the other Party, providing a free-of-charge
option to assume the prosecution or maintenance thereof. The Parties agree that
any of the periods of time specified in this Section 12.2(c) shall be shortened
as may be required to ensure that rights in the relevant Joint Patent Right are
not lost. All out-of-pocket costs incurred in the filing, prosecution and
maintenance of any Joint Patent Rights shall be treated as a Shared Promotion
Expense shared between the Parties as set forth in Section 9.2(c).

                  (d)      Cooperation. Each Party agrees to cooperate with the
other with respect to the preparation, filing, prosecution and maintenance of
Patents and Patent Applications pursuant to this Section 12.2, including,
without limitation, the execution of all such documents and instruments and the
performance of such acts (and causing its relevant employees to execute such
documents and instruments and to perform such acts) as may be reasonably
necessary in order to permit the other Party to continue any preparation,
filing, prosecution or maintenance of Joint Patent Rights that such Party has
elected not to pursue as provided for in Section 12.2(b). The IPSC shall
recommend to the JOC which of the Novartis Patent Rights, Regeneron Patent
Rights and Joint Patent Rights for which to seek an extension of term. Upon
confirmation of the recommendation of the IPSC with respect to patent term
extension by the JOC, the selected Party will file for said patent term
extension, and the Parties shall bear the costs thereof in the same manner as
the Parties bear the expenses for the filing, prosecution and maintenance of
such Patent Rights in accordance with the provisions of this Section 12.2.

                                  ARTICLE XIII

                        INTELLECTUAL PROPERTY LITIGATION

                  13.1 Third Party Infringement Suits.

                  (a)      In the event that either Party or any of its
Affiliates becomes aware of an infringement of a Novartis Patent Right, a
Regeneron Patent Right, or a Joint Patent Right by a Third Party's activities in
the applicable Territory, the Party that became aware of the infringement shall
promptly notify the other Party in writing of this claim or assertion and shall
provide such other Party with all available evidence supporting such known or
suspected infringement or unauthorized use. As soon as reasonably practicable
after the receipt of such notice, the Parties shall cause the IPSC to meet and
consider the appropriate course of action with respect to such infringement.

                  (b)      With respect to any infringement by virtue of a Third
Party's activities with respect to a product which is a Competing Product, the
IPSC will determine whether infringement litigation or settlement discussions
with the infringer should be undertaken. If the IPSC decides that any such
infringement litigation should be undertaken, the IPSC will also decide which
Party is to be the Lead Litigation Party ("Lead Litigation Party"). The

                                      -65-

<PAGE>

Lead Litigation Party will have the right bring and prosecute, or defend, such
infringement suits as may be necessary to cause the infringer to cease
activities with respect to any such Competing Product, the manufacture, use,
sale, offer for sale or import of which would infringe said Novartis Patent
Right, Regeneron Patent Right, or Joint Patent Right in the applicable
Territory. Upon confirmation of the IPSC decision by the JOC, the Lead
Litigation Party will bring and prosecute an infringement suit, and/or defend a
declaratory judgment action, as appropriate, against such infringing Third
Party. The Lead Litigation Party will select litigation counsel of its choosing.
The Lead Litigation Party will pay all litigation costs. The non-Lead Litigation
Party will provide reasonable assistance to the Lead Litigation Party in
prosecuting any suit, and if required by law, will join in the suit. The
non-Lead Litigation Party shall have the right to join in any litigation at its
sole discretion and expense. The amount of any recovery from any such
infringement suit, whether in damages or by settlement, will be included in the
Net Sales figure for such Co-Commercialization Country for the quarter in which
the recovery is paid to the Lead Litigation Party. In the event that there is
more than one IL-1 Product at the time of such recovery, then the amount of any
such recovery shall be allocated between such IL-1 Products as determined by the
IPSC.

                  (c)      With respect to any infringement by virtue of a Third
Party's activities with respect to any product which is not a Competing Product,
then (i) Regeneron, with respect to any Regeneron Patent Rights, (ii) Novartis
with respect to any Novartis Patent Rights, and (iii) either Party, with respect
to any Joint Patent Rights, shall have the right (but not the obligation to
bring and prosecute an infringement suit, and/or defend a declaratory judgment
action, as appropriate, against such infringing Third Party. The other Party
will provide reasonable assistance to the litigating Party, at the litigating
Party's reasonable expense, in prosecuting any suit, and if required by law,
will join in the suit. All amounts received by way of any recovery from any such
infringer, whether in damages or by settlement, shall be to the benefit of the
litigating Party.

                  13.2 Patent Marking. Each Party shall comply with the patent
marking statutes in each country in which an IL-1 Product is made, offered for
sale, sold or imported by such Party, its Affiliates and/or sublicensees.

                  13.3 Third Party Infringement Claims.

                  (a)      The provisions of this Section 13.3 shall be subject
to the provisions of Article XVII, which shall govern as to both costs and
procedures in the event of infringement actions relating to any IL-1 Product
brought by a Third Party against either Party in which the Third Party claim(s),
if true, would constitute a breach of representation or warranty set forth in
Section 15.2.

                  (b)      If either Party or its Affiliates shall learn of a
claim or assertion that the manufacture, Development or Commercialization of any
IL-1 Product infringes or otherwise violates the intellectual property rights of
any Third Party, then such Party shall promptly notify the other Party in
writing of this claim or assertion. As soon as reasonably practicable after the
receipt of such notice, the Parties shall cause the IPSC to meet and consider
the appropriate course of action with respect to such allegation of
infringement.

                  (c)      If only one Party defends any claimed infringement
action commenced by a Third Party alleging that the manufacture, Development or
Commercialization of any IL-1 Product infringes or otherwise violates the
intellectual property rights of such Third

                                      -66-

<PAGE>

Party, the other Party and its Affiliates shall assist and cooperate in any such
infringement litigation at the defending Party's (or its Affiliates') reasonable
request.

                  13.4 Amgen License. During the term of this Agreement,
Novartis agrees and covenants to the extent permitted by applicable Law that it
shall not institute or prosecute any claim, action, or suit at law or in equity
seeking to have any claim in any "Immunex IL-1r Patent Right" or "Amgen Licensed
Patent Right" (as each such term is defined in the Amgen License Agreement)
declared invalid or unenforceable; provided, however, that nothing herein shall
prohibit Novartis from either (i) asserting any and all defenses available to it
if it is sued for infringement, including, without limitation, assertions
relating to the validity or enforceability of the Immunex IL-1r Patent Rights
and/or Amgen Licensed Patent Rights, or (ii) asserting any and all defenses,
evidence, and arguments, including, without limitation, lack of patentability of
the subject matter of a count or claim and lack of support for a count or claim,
in any interference involving a Patent or Patent Application included within the
definition of Immunex IL-1r Patent Right or Amgen Licensed Patent Rights.

                                  ARTICLE XIV

             BOOKS, RECORDS AND INSPECTIONS; AUDITS AND ADJUSTMENTS

                  14.1 Books and Records. Each Party shall, and shall cause each
of its respective Affiliates to, keep proper books of record and account in
which full, true and correct entries (in conformity with IAS or GAAP (as
applicable, depending on which accounting principles such entity uses to
maintain its accounting books and records) as generally and consistently applied
and all requirements of Law) shall be made of all dealings and transactions in
relation to this Agreement. Each Party shall, and shall cause each of its
respective Affiliates to, permit auditors, as provided in Section 14.2, to visit
and inspect, during regular business hours and under the guidance of officers of
the Party being inspected, and to examine the books of record and account of
such Party or such Affiliate to the extent relating to this Agreement and
discuss the affairs, finances and accounts of such Party or such Affiliate to
the extent relating to this Agreement with, and be advised as to the same by,
its and their officers and independent accountants.

                  14.2 Audits and Adjustments.

                  (a)      Each Party shall have the right (at its costs), upon
no less than thirty (30) days advance notice and at such reasonable times and
intervals and to such reasonable extent as the investigating Party shall
request, not more than once during any year, to have the books and records of
the other Party and its Affiliates to the extent relating to this Agreement for
the preceding two years audited by an independent "Big Four" (or equivalent)
accounting firm of its choosing under reasonable appropriate confidentiality
provisions, for the sole purpose of verifying the accuracy of all financial,
accounting and numerical information and calculations provided under this
Agreement, including, without limitation, the numbers of Details, the reports
and payments provided under this Agreement and corresponding provisions of the
Ancillary Agreements (for greater clarity, the Parties agree that the
establishment of COGS shall not be subject to this Article XIV). Audits under
this Section 14.2 shall not be based on data provided by Third Party data
sources.

                  (b)      The results of any such audit shall be delivered in
writing to each Party and shall be final and binding upon the Parties, unless
disputed by a Party within ninety (90) days. Unless otherwise mutually agreed by
the Parties, any disputes regarding the results of

                                      -67-

<PAGE>

any such audit shall be subject to the dispute resolution procedures set forth
in Section 10.2. If the audited Party or its Affiliates have underpaid or
overbilled an amount due under this Agreement resulting in a cumulative
discrepancy during any year of more than ten percent (10%), the audited Party
shall also reimburse the other Party for the costs of such audit (with the cost
of the audit to be paid by the auditing party in all other cases). Such
accountants shall not reveal to the Party seeking verification the details of
its review, except for such information as is required to be disclosed under
this Agreement, and shall be subject to the confidentiality provisions contained
in Article XVI.

                  (c)      If any examination or audit of the records described
above discloses an under- or over-payment of amounts due hereunder, then unless
the result of the audit is to be contested pursuant to Section 14.2(b) above,
the Party (or its Affiliate) owing any money hereunder shall pay the same (plus
interest thereon at the Default Interest Rate from the date of such underpayment
or overpayment through the date of payment of the amount required to be paid
pursuant to this Section 14.2(c)) to the Party (or its Affiliate) entitled
thereto within thirty (30) days after receipt of the written results of such
audit pursuant to this Section. In the event that any examination or audit of
Detailing records indicates a shortfall in the number of Details carried out by
a Party or its Affiliate, the amount due in relation to such shortfall shall be
calculated and paid in accordance with the provisions of Section 9.2(a)(iii) and
Section 6.10 above.

                  14.3 Accounting Standards. Except as otherwise provided
herein, all costs and expenses and other financial determinations with respect
to this Agreement shall be determined in accordance with International
Accounting Standards as generally and consistently applied.

                                   ARTICLE XV

                         REPRESENTATIONS AND WARRANTIES

                  15.1 Due Organization, Valid Existence and Due Authorization.
Each Party hereto represents and warrants to the other Party as follows: (a) it
is duly organized and validly existing under the Laws of its place of
incorporation; (b) it has full corporate power and authority and has taken all
corporate action necessary to enter into and perform this Agreement; (c) the
execution and performance by it of its obligations hereunder will not constitute
a breach of, or conflict with, its organizational documents nor any other
material agreement or arrangement, whether written or oral, by which it is
bound; (d) to the best of its knowledge, it has complied in all material
respects with all Laws applicable to it; (e) this Agreement is its legal, valid
and binding obligation, enforceable in accordance with the terms and conditions
hereof (subject to applicable Laws of bankruptcy and moratorium); and (f) no
broker, finder or investment banker is entitled to any brokerage, finder's or
other fee in connection with this Agreement or the transactions contemplated
hereby based on arrangements made by it or on its behalf.

                  15.2 Intellectual Property.

                  (a)      Regeneron represents and warrants to Novartis that,
as of the Effective Date, (a) [*************************************] it owns or
has all necessary licenses or rights within its jurisdiction to use the Trap-1
Product and the Trap-2 Product, (b) [***************************], neither the
manufacturing of any Trap-1

                                      -68-

<PAGE>

Product or Trap-2 Product nor the Development, promotion, marketing and sale of
any the Trap-1 Product or Trap-2 Product by the Parties will infringe upon any
valid rights of any other Person and it has not received any written notice
alleging any such infringement, (c) the rights granted by Regeneron to Novartis
and its Affiliates hereunder do not, to Regeneron's knowledge, conflict with
rights granted by Regeneron to any Third Party and (d) Regeneron has not
received any notice concerning the institution or possible institution of any
interference involving any Regeneron Patent, nor has it made any application for
reissuance or filed any request for reexamination with respect to any such
Patent.

                  (b)      Novartis represents and warrants to Regeneron that,
as of the Effective Date, (a) [**********************], it owns or has all
necessary licenses or rights within its jurisdiction to use the IL-1 Antibody
Product, (b) [****************************], neither the manufacturing of the
IL-1 Antibody Product nor the Development, promotion, marketing and sale of the
IL-1 Antibody Product by the Parties will infringe upon any valid rights of any
other Person and it has not received any written notice alleging any such
infringement, (c) the rights granted by Novartis to Regeneron and its Affiliates
hereunder do not, to Novartis' knowledge, conflict with rights granted by
Novartis to any Third Party and (d) Novartis has not received any notice
concerning the institution or possible institution of any interference involving
any Novartis Patent and nor has it made any application for reissuance or filed
any request for reexamination with respect to any such Patent.

                  15.3 Disclaimer. Except as expressly set forth herein, no
Party makes any express or implied warranties, statutory or otherwise,
concerning the value, adequacy, freedom from fault of, other quality,
efficiency, stability, characteristics or usefulness of, or merchantability, or
fitness for a particular purpose of, any IL-1 Product.

                                   ARTICLE XVI

                                 CONFIDENTIALITY

                  16.1 Confidential Company Information.

                  (a)      Each of Novartis and Regeneron acknowledges (subject
to Section 16.1(b)) that: (i) all Company Information provided by the other
Party or its respective Affiliates pursuant to this Agreement is confidential
and proprietary to such other Party or its respective Affiliates, and (ii) all
New Information is confidential and proprietary to the Parties, and each of
Novartis and Regeneron agrees to (A) maintain such information in confidence
during the last to expire Term of this Agreement and for a period of ten (10)
years thereafter and (B) use such information solely for the purpose of
performing its obligations hereunder. Each of Novartis and Regeneron covenants
that neither it nor any of its respective Affiliates shall disclose any such
information to any Third Party except to its employees, agents or any other
person under its authorization; provided such employees, agents or persons under
its authorization are subject in writing to substantially the same
confidentiality obligations as the Parties and their respective Affiliates.

                  (b)      Notwithstanding anything provided above, the
restrictions provided in this Article XVI shall not apply to information that is
(and such information shall not be considered confidential or proprietary under
this Agreement) (i) already in the public domain as of the Effective Date by
reason of prior publication or otherwise; (ii) received by a receiving Party on
an unrestricted basis from a Third Party not under an obligation of
confidentiality to the other Party or any Affiliate of such other Party with
respect to such information; (iii) information that has become part of the
public domain after the Effective

                                      -69-

<PAGE>

Date through no act, omission or fault of the receiving Party; or (iv)
information that is similar in nature to the purported Company Information but
has been independently created, as evidenced by written or electronic
documentation. If a receiving Party is required by applicable Law to disclose
any Company Information to a Governmental Authority, then the receiving Party
shall promptly notify the disclosing Party of such disclosure and the
procedures, such as a protective order, instituted to protect the
confidentiality of the Company Information to be disclosed.

                  (c)      Notwithstanding anything provided above, Regeneron
shall have the right to disclose to any Regeneron licensee of Trap-1 or Trap-2
in Japan: (i) such information as to adverse events and safety as is required
under applicable Laws; and (ii) such information as is included in a top-level
report summarizing Clinical Trials planned and underway with respect to Trap-1
and/or Trap-2 pursuant to this Agreement, which report shall be prepared by
Novartis for purposes of this Section 16.1(c) and shall refer expressly to this
Section 16.1(c); provided, however, that any such disclosure of information
shall be subject to confidentiality obligations on the part of such licensee
reasonably satisfactory to Novartis.

                  16.2 Injunctive Relief. Each Party acknowledges that damages
resulting from disclosure of Company Information would be an inadequate remedy
and that, notwithstanding the provisions of Article X, in the event of any such
disclosure or any indication of an intent to disclose such information, a Party
(or its Affiliates) owning such Company Information, and each Party, with
respect to New Information, shall be entitled to seek, by way of private
litigation, injunctive relief or other equitable relief in addition to any and
all remedies available at law or in equity, including the recovery of damages
and reasonable attorneys' fees, and in any such action for equitable relief in a
court of competent jurisdiction, the Parties hereby consent to the jurisdiction
of such for such purpose and will not assert as a defense that there is an
adequate remedy at law.

                  16.3 Publication of New Information. Subject to JOC approval,
if either Novartis or Regeneron (the "Publishing Party") desires to disclose any
New Information or such other Company Information which relates to any IL-1
Product in scientific journals, publications or scientific presentations or
otherwise, the Publishing Party shall provide the other Party an advance copy of
any proposed publication or summary of a proposed oral presentation relating to
the New Information or such other Company Information prior to submission for
publication or disclosure. Such other Party shall have a reasonable opportunity
to recommend any changes it reasonably believes are necessary to preserve the
New Information or such other Company Information, and the incorporation of such
recommended changes shall not be unreasonably refused. If such other Party
informs the Publishing Party, within thirty (30) days of receipt of an advance
copy of a proposed publication or summary of a proposed oral presentation, that
such publication in its reasonable judgment could be expected to have a material
adverse effect on the commercial value of any New Information or such other
Company Information, the Publishing Party shall delay or prevent such disclosure
or publication as proposed by the other Party. In the case of patentable
inventions, the delay shall be sufficiently long to permit the timely
preparation and filing of a patent application(s) or application(s) for a
certificate of invention on the information involved, provided, however, that
the Party owning such information shall be entitled to prevent such disclosure
or publication if in its commercially reasonable judgment such patent
application will not reasonably protect the commercial value of such New
Information or Company Information or if in its commercially reasonable judgment
such disclosure or

                                      -70-

<PAGE>

publication would otherwise have a material adverse effect on the commercial
value of any such information.

                  16.4 Other Publications. During the Term, Novartis and
Regeneron agree not to issue any press releases or public announcements
concerning this Agreement, the Stock Purchase Agreement or any Ancillary
Agreement (and to ensure that their respective Affiliates do not do so) without
the prior written consent of the other Party to the form, timing and content of
any such release of announcement, except as required by a Governmental Authority
and applicable Law; provided, however, that either Party may issue press
releases or public announcements which incorporate information concerning this
Agreement which information was included in a press release or public
announcement which was approved by the other Party as an initial press release
concerning this Agreement. Neither Party shall unreasonably withhold or delay
its consent to any such press release or announcement. Except as required by
Law, neither Party (or their respective Affiliates) shall disclose to any Third
Party, under any circumstances, any financial terms of this Agreement that have
not been previously disclosed publicly pursuant to this Article XVI without the
prior written consent of the other Party, which consent shall not be
unreasonably withheld.

                                  ARTICLE XVII

                                    INDEMNITY

                  17.1 Indemnity and Insurance.

                  (a)      Each Party shall indemnify and hold harmless the
other Party, its Affiliates and their respective officers, directors, employees
and agents from and against all claims, demands, liabilities, damages and
expenses, including reasonable attorneys' fees and costs (collectively,
"Damages"), arising out of:

                  (i)      the negligence, recklessness, bad faith, intentional
         wrongful acts or omissions of the Indemnifying Party or its Affiliates
         (or, to the extent permitted under this Agreement, their respective
         agents, contractors, distributors, representatives or other persons or
         entities working on their behalf), including, without limitation, in
         connection with the Co-Development and Co-Commercialization of any IL-1
         Product, except to the extent that Damages arise out of the negligence,
         recklessness, bad faith or intentional wrongful acts, or omissions
         committed by the Indemnified Party or its Affiliates (or, to the extent
         permitted under this Agreement, their respective agents, contractors,
         representatives or other persons or entities working on their behalf);
         and

                  (ii)     breach by the Indemnifying Party (or conduct by any
         of its Affiliates, which if performed by the Indemnifying Party would
         be a breach by the Indemnifying Party) of the terms of, or the
         representations and warranties made by it in, this Agreement or any
         applicable Ancillary Agreement to which it is a party; provided,
         however, that the payments and adjustments provided for in Section 9.2
         (a)(iii) and Section 6.10 shall be the exclusive remedy with respect to
         any shortfall in the provision of Details.

                  (b)      Each Party will maintain, or self-insure for, product
liability insurance to cover liabilities related to the development,
manufacture, Co-Commercialization, marketing, distribution, sale and use of IL-1
Products at a commercially reasonable level.

                                      -71-

<PAGE>

                  17.2 Indemnity Procedure.

                  (a)      The Party entitled to indemnification under this
Article XVII (an "Indemnified Party") shall notify the Party potentially
responsible for such indemnification (the "Indemnifying Party") within ten (10)
Business Days of becoming aware of any claim or claims asserted or threatened
against the Indemnified Party which could give rise to a right of
indemnification under this Agreement; provided, however, that the failure to
give such notice shall not relieve the Indemnifying Party of its indemnity
obligation hereunder except to the extent that such failure materially
prejudices its rights hereunder.

                  (b)      If the Indemnifying Party has acknowledged in writing
to the Indemnified Party the Indemnifying Party's responsibility for defending
such claim, the Indemnifying Party shall have the right to defend, at its sole
cost and expense, such claim by all appropriate proceedings, which proceedings
shall be prosecuted diligently by the Indemnifying Party to a final conclusion
or settled at the discretion of the Indemnifying Party; provided, however, that
the Indemnifying Party may not enter into any compromise or settlement unless
(i) such compromise or settlement includes as an unconditional term thereof, the
giving by each claimant or plaintiff to the Indemnified Party of a release from
all liability in respect of such claim; and (ii) the Indemnified Party consents
to such compromise or settlement, which consent shall not be withheld or delayed
unless such compromise or settlement involves (A) any admission of legal
wrongdoing by the Indemnified Party, (B) any payment by the Indemnified Party
that is not indemnified hereunder or (C) the imposition of any equitable relief
against the Indemnified Party.

                  (c)      The Indemnified Party may participate in, but not
control, any defense or settlement of any claim controlled by the Indemnifying
Party pursuant to this Section 17.2 and shall bear its own costs and expenses
with respect to such participation; provided, however, that the Indemnifying
Party shall bear such costs and expenses if counsel for the Indemnifying Party
shall have reasonably determined that such counsel may not properly represent
both the Indemnifying Party and the Indemnified Party.

                                  ARTICLE XVIII

                                  FORCE MAJEURE

         In the event of strikes, lock-outs or other industrial disturbances,
rebellions, mutinies, epidemics, landslides, lightning, earthquakes, fires,
storms, floods, sinking, drought, civil disturbances or explosions, acts or
decisions of duly constituted municipal, state or national Governmental
Authorities or of courts of Law, as well as impossibility to obtain equipment,
supplies, fuel or other required materials, in spite of having acted with
commercially reasonable diligence, or by reason of any other causes which are
not under the control of the Party requesting the abatement of the performance
or causes due to circumstances which could not reasonably be foreseen and which
are not possible to eliminate or overcome with due diligence by such Party
("Force Majeure"), the Parties agree that, if either Novartis or Regeneron finds
itself wholly or partially unable to fulfill its respective obligations in this
Agreement by reasons of Force Majeure, the Party affected will advise the other
Party in writing of its inability to perform, giving a detailed explanation of
the occurrence of the event which excuses performance as soon as possible after
the cause or event has occurred. If such notice is given, the performance of the
Party giving the notification, except the payment of funds, shall be abated, and
any time deadlines shall be extended for so long as performance may be prevented
by Force Majeure. Except for the payment of funds that are or become due

                                      -72-

<PAGE>

and payable, neither Party shall be required to make up any performance that was
prevented by Force Majeure. In no event will any Force Majeure extend beyond one
hundred eighty (180) days.

                                  ARTICLE XIX

                              TERM AND TERMINATION

                  19.1 Term. The "Term" of this Agreement shall commence on the
Effective Date and shall expire on a country-by-country and product-by-product
basis pursuant to Section 19.2 below, unless sooner terminated as provided
herein. This Agreement may not be terminated except as specifically provided in
this Agreement, and to the extent this Agreement is terminated as specifically
provided in this Agreement, the "Term" shall be deemed to have terminated to the
same extent.

                  19.2 Expiration of Term.

                  (a)      Expiration of Term. The Term of this Agreement shall
expire with respect to a particular IL-1 Product on a country-by-country basis
in each country in the applicable Territory for such IL-1 Product, (i) at such
time as, after annual (based on a calendar year) gross sales of such IL-1
Product in such country have exceeded $1 million, such annual gross sales of
such IL-1 Product in such country fall below $1 million (unless such decline of
such annual gross sales of such IL-1 Product in such country to below $1 million
is due to in whole or in part to conditions which are reasonable likely not to
be of a long-term nature); or (ii) as otherwise agreed by the Parties as
evidenced in writing.

                  (b)      Effect of Expiration of Trap-1 Term. Upon expiration
of the Term of this Agreement with respect to the Trap-1 Product in a country as
contemplated by Section 19.2(a), all licenses and rights with respect to the
Trap-1 Product in such country granted to Novartis hereunder shall automatically
terminate and revert to Regeneron and in such event, the provisions of Part A of
SCHEDULE 19 shall apply with respect to the Trap-1 Product in such country as if
the Trap-1 Product is a "Terminated Product".

                  (c)      Effect of Expiration of IL-1 Antibody Term. Upon
expiration of the Term of this Agreement with respect to the IL-1 Antibody
Product in a country as contemplated by Section 19.2(a), all licenses and rights
with respect to the IL-1 Antibody Product in such country granted to Regeneron
hereunder shall automatically terminate and revert to Novartis and in such
event, the provisions of Part B of SCHEDULE 19 shall apply with respect to the
IL-1 Antibody Product in such country as if the IL-1 Antibody Product is a
"Terminated Product".

                  (d)      Effect of Expiration of Trap-2 Term. Upon expiration
of the Term of this Agreement with respect to the Trap-2 Product in a country as
contemplated by Section 19.2(a), all licenses and rights with respect to the
Trap-2 Product in such country granted to Novartis hereunder shall automatically
terminate and revert to Regeneron and in such event, the provisions of Part A of
SCHEDULE 19 shall apply with respect to the Trap-2 Product in such country as if
the Trap-2 Product is a "Terminated Product".

                                      -73-

<PAGE>

                  19.3 Termination By Mutual Agreement in Special Circumstances

                  (a)      Upon the mutual agreement of the Parties, this
Agreement may be terminated on a product-by-product basis with respect to the
entire Territory for a particular IL-1 Product, on the occurrence of one or more
of the following events:

                  (i)      formulation failure for such IL-1 Product, including,
         without limitation, technical failure during development of drug
         product and/or formulation, unacceptable levels of degradation products
         (whether unacceptable for regulatory Approvals or toxicologically
         unacceptable), or drug product performance failing to meet the
         requirements of Regulatory Authorities;

                  (ii)     unacceptable safety concerns with respect to such
         IL-1 Product;

                  (iii)    failure to meet the Trial Success Criteria
         established by the JOC for Phase II Clinical Trials for such IL-1
         Product;

                  (iv)     unacceptable outcome of meetings with FDA and/or EMEA
         to define the scope of the Phase III Clinical Trials for such IL-1
         Product; or

                  (v)      failure to meet the Trial Success Criteria
         established by the JOC for Phase III Clinical Trials for such IL-1
         Product.

In the event of any termination of this Agreement by mutual agreement of the
Parties with respect to an IL-1 Product pursuant to this Section 19.3, as part
of such mutual agreement: (i) the Parties shall agree upon an orderly wind down
of all Development activities for the terminated IL-1 Product (including,
without limitation, those being performed by their Affiliates or Third Party
contractors) and each Party shall make all payments due and owing to one another
and to Third Parties, provided, however, that if so provided in such mutual
agreement, no Party shall be required to pay to the other Party any milestone
payment pursuant to Section 9.4 with respect to the terminated IL-1 Product; and
(ii) all licenses and rights with respect to the terminated IL-1 Product granted
by one Party to the other Party hereunder shall automatically terminate and
revert to the granting Party.

                  (b)      If on the occurrence of one or more of the events
with respect to an IL-1 Product described in Section 19.3(a) above, the Parties
are unable to reach mutual agreement regarding termination of this Agreement
with respect to such IL-1 Product, then a Party may terminate this Agreement
with respect to the entire Territory for such IL-1 Product, provided that any
such termination shall require the notice, and shall otherwise be treated for
all purposes as, and shall be subject to all of the terms and conditions
applicable to, termination pursuant to Section 19.4 (including SCHEDULE 19). In
the event a Party terminates this Agreement with respect to an IL-Product as
described above in this Section 19.3(b) due to perceived unacceptable safety
concerns, including safety related issues associated with the formulation of
drug product, the other Party shall indemnify the terminating Party from and
against any and all Damages arising out of Third Party claims relating to such
safety concerns or issues which are based upon the other Party's continuing
efforts during the Trap-1 Termination Notice Period, Trap-2 Termination Notice
Period or IL-1 Antibody Termination Notice Period, as applicable, in support of
the continued Development and/or Commercialization of such IL-1 Product.

                                      -74-

<PAGE>

                  19.4 Termination Without Cause.

                  (a)      Trap-1. Novartis may terminate this Agreement with
respect to the entire Territory for all Trap-1 Products on (i) nine (9) months'
written notice to Regeneron at any time prior to the first Launch of a Trap-1
Product in the Trap-1 Territory; and (ii) twelve (12) months' written notice to
Regeneron at any time after the first Launch of a Trap-1 Product in the Trap-1
Territory. Except as otherwise provided below in this Section 19.4(a), the
Agreement shall continue in full force and effect with respect to the Trap-1
Product through the applicable notice period set forth above (the "Trap-1
Termination Notice Period"), provided that Novartis shall not be required to pay
to Regeneron any milestone payment in respect of the Trap-1 Product which is
achieved during the Trap-1 Termination Notice Period. Upon expiration of the
Trap-1 Termination Notice Period, or earlier to the extent provided below in
this Section 19.4(a), all licenses and rights with respect to the Trap-1 Product
in such country granted to Novartis hereunder shall automatically terminate and
revert to Regeneron (except to the extent required by Novartis to fulfill its
obligations pursuant to Part A of SCHEDULE 19, and upon the earlier of such
fulfillment or written notice from Regeneron that it will not require such
fulfillment, such licenses and rights, to the extent not previously terminated,
shall automatically terminate and revert to Regeneron), and the provisions of
Part A of SCHEDULE 19 shall apply with respect to the Trap-1 Product in such
country as if the Trap-1 Product is a "Terminated Product". During the Trap-1
Termination Notice Period, to the extent set forth or requested in one or more
written notices from Regeneron to Novartis hereunder (i) such licenses and
rights granted to Novartis shall automatically terminate as of a date specified
in such notice(s) (but not later than the Trap-1 Termination Notice Period) and
(ii) Novartis will promptly take the actions required by Part A of SCHEDULE 19
to facilitate Regeneron's (or its nominee's) expeditious assumption during the
Trap-A Termination Notice Period, with as little disruption as reasonably
possible, of the continued Development and/or Commercialization of Terminated
Product(s).

                  (b)      IL-1 Antibody. Regeneron may terminate this Agreement
with respect to the entire Territory for IL-1 Antibody Products, on (i) nine (9)
months' written notice to Novartis at any time prior to the first Launch of such
IL-1 Antibody Product in the IL-1 Antibody Territory; and (ii) twelve (12)
months' written notice to Novartis at any time after the first Launch of such
IL-1 Antibody Product in the IL-1 Antibody Territory. Except as otherwise
provided below in this Section 19.4(b), the Agreement shall continue in full
force and effect with respect to the IL-1 Antibody Product through the
applicable notice period set forth above (the "IL-1 Antibody Termination Notice
Period"), provided that Regeneron shall not be required to pay to Novartis any
milestone payment in respect of the IL-1 Antibody Product which is achieved
during the IL-1 Antibody Termination Notice Period. Upon expiration of the IL-1
Antibody Termination Notice Period, or earlier to the extent provided below in
this Section 19.4(b), all licenses and rights with respect to the IL-1 Antibody
Product in such country granted to Regeneron hereunder shall automatically
terminate and revert to Novartis (except to the extent required by Regeneron to
fulfill its obligations pursuant to Part B of SCHEDULE 19, and upon the earlier
of such fulfillment or written notice from Novartis that it will not require
such fulfillment, such licenses and rights, to the extent not previously
terminated, shall automatically terminate and revert to Novartis), and the
provisions of Part B of SCHEDULE 19 shall apply with respect to the IL-1
Antibody Product in such country as if the IL-1 Antibody Product is a
"Terminated Product". During the IL-1 Antibody Termination Notice Period, to the
extent set forth or requested in a written notice from Novartis to Regeneron (i)
such licenses and rights granted to Novartis hereunder shall automatically
terminate as of a date specified in such notice (but not later than the IL-1

                                      -75-

<PAGE>

Antibody Termination Notice Period) and (ii) Regeneron will promptly take the
actions required by Part A of SCHEDULE 19 to facilitate Novartis' expeditious
assumption during the IL-1 Antibody Termination Notice Period, with as little
disruption as a reasonably possible, of the continued Development and/or
Commercialization of Terminated Products.

                  (c)      Trap-2. Novartis may terminate this Agreement with
respect to the entire Territory for all Trap-2 Products on (i) nine (9) months'
written notice to Regeneron at any time prior to the first Launch of a Trap-2
Product in the Trap-2 Territory; and (ii) twelve (12) months' written notice to
Regeneron at any time after the first Launch of a Trap-2 Product in the Trap-2
Territory. Except as otherwise provided in this Section 19.4(c), the Agreement
shall continue in full force and effect with respect to the Trap-2 Product
through the applicable notice period set forth above (the "Trap-2 Termination
Notice Period"), provided that Novartis shall not be required to pay to
Regeneron any milestone payment in respect of the Trap-2 Product which is
achieved during the Trap-2 Termination Notice Period. Upon expiration of the
Trap-2 Termination Notice Period, or earlier to the extent provided below in
this Section 19.4(c), all licenses and rights with respect to the Trap-2 Product
in such country granted to Novartis hereunder shall automatically terminate and
revert to Regeneron (except to the extent required by Novartis to fulfill its
obligations pursuant to Part A or SCHEDULE 19, and upon earlier of such
fulfillment or written notice from Regeneron that it will not require such
fulfillment, such licenses and rights, to the extent not previously terminated,
shall automatically terminate and revert to Regeneron), and the provisions of
Part A of SCHEDULE 19 shall apply with respect to the Trap-2 Product in such
country as if the Trap-2 Product is a "Terminated Product".

                  19.5 Termination For Material Breach. Upon and subject to the
terms and conditions of this Section 19.5, this Agreement shall be terminable by
a Party on a product-by-product basis with respect to the entire Territory for a
particular IL-1 Product, or on a country-by-country basis with respect to any
particular Co-Promotion Country, Co-Branding Country or Co-Marketing Country,
upon written notice to the other Party, (i) with respect to the entire Territory
for a particular IL-1 Product, if the other Party commits a material breach of
this Agreement that is material to the Parties' collaboration with respect to
such IL-1 Product as contemplated by this Agreement taken as a whole, or (ii)
with respect to a particular Co-Promotion Country, Co-Branding Country or
Co-Marketing Country for a particular IL-1 Product if the other Party commits a
material breach of this Agreement that is material to the Parties' collaboration
with respect to such IL-1 Product in such Co-Promotion Country, Co-Branding
Country or Co-Marketing Country, as applicable, as contemplated by this
Agreement. Such notice of termination shall set forth in reasonable detail the
facts underlying or constituting the alleged breach (and specifically
referencing the provisions of this Agreement alleged to have been breached), and
the termination which is the subject of such notice shall be effective ninety
(90) days after the date such notice is given unless the breaching Party shall
have cured such breach within such ninety (90) day period (or, if such material
breach, by its nature, is a curable breach but such breach is not curable within
such ninety (90) day period, such longer period not to exceed one hundred eighty
(180) days so long as the breaching party is using diligent efforts to cure such
breach, in which event if such breach has not been cured, such termination shall
be effective on the earlier of the expiration of such one hundred eighty (180)
day period or such time as the breaching party ceases to use diligent efforts to
cure such breach). Notwithstanding the foregoing, in the case of breach of a
payment obligation hereunder, the ninety (90) day period referred to in the
immediately preceding sentence shall instead be thirty (30) days (and the
immediately preceding parenthetical clause in the immediately preceding sentence
shall not apply). As

                                      -76-

<PAGE>

used in this Section 19.5, the term "material breach" shall mean a breach by a
Party that substantially undermines the benefits reasonably expected to be
realized by the other Party from the collaboration hereunder, such that
termination of this Agreement, and the consequences thereof provided for herein,
are appropriate and equitable remedies. Notwithstanding any term or provision
this Agreement, in no event will a Party's failure to provide Details, for any
reason, or no reason, constitute a material breach for purposes of this Section
19.5 or otherwise constitute a cause or basis for termination of this Agreement
in whole or in part.

                  19.6 Insolvency. Either Party shall have the right to
terminate this Agreement in its entirety if, at any time, (i) the other Party
shall file in any court or agency pursuant to any statute or regulation of any
state or country, a petition in bankruptcy or insolvency or for reorganization
or for an arrangement or for the appointment of a receiver or trustee of the
Party or of its assets, or (ii) if the other Party proposes a written agreement
of composition or extension of its debts, or (iii) if the other Party shall be
served with an involuntary petition against it, filed in any insolvency
proceeding, and such petition shall not be dismissed within sixty (60) days
after the filing thereof, or (iv) if the other Party shall propose or be a party
to any dissolution or liquidation, or (v) if the other Party shall make an
assignment for the benefit of creditors. In the event that this Agreement is
terminated or rejected by a Party or its receiver or trustee under applicable
bankruptcy Laws due to such Party's bankruptcy, then all rights and licenses
granted under or pursuant to this Agreement by such Party to the other Party
are, and shall otherwise be deemed to be, for purposes of Section 365(n) of the
U.S. Bankruptcy Code and any similar Laws in any other country in the Territory,
licenses of rights to "intellectual property" as defined under Section 101(52)
of the U.S. Bankruptcy Code. The Parties agree that all intellectual property
rights licensed hereunder, including, without limitation, any patents or patent
applications in any country of a party covered by the license grants under this
Agreement, are part of the "intellectual property" as defined under Section
101(52) of the Bankruptcy Code subject to the protections afforded the
non-terminating Party under Section 365(n) of the Bankruptcy Code, and any
similar law or regulation in any other country.

                  19.7 Termination for Change of Control.

                  (a)      Within ninety (90) days following consummation of a
Change of Control of Regeneron which results in Regeneron being owned or
controlled by a major Third Party pharmaceutical company with an annual turnover
in excess of $10 billion, Novartis shall have the right to notify Regeneron of
its intent to terminate this Agreement in its entirety (the "Change of Control
Notice"). Following delivery of the Change of Control Notice, the Parties will
negotiate in good faith to enter into an exclusive license agreement pursuant to
which Novartis will be granted exclusive rights to manufacture, Develop and
Commercialize the IL-1 Products in the applicable Territory on mutually agreed
terms. The license shall be subject to a royalty based on net sales which shall,
to the greatest extent possible, mirror the economic terms set forth in the
Agreement over the lives of the applicable IL-1 Products. The royalty rates and
other payments shall be dependent upon the stage of Development and/or
Commercialization of the IL-1 Products and the anticipated future profitability
of such IL-1 Products and shall also take into account the efforts and expenses
to be incurred by Novartis in Developing and Commercializing the IL-1 Products.
The royalty rate and other terms and conditions shall be determined by the
mutual agreement of the Parties after good faith negotiations provided, however,
that if the Parties are unable to reach mutual agreement thereon within three
(3) months after delivery of the Change of

                                      -77-

<PAGE>

Control Notice, the matter shall be submitted for arbitration in accordance with
the terms of Article X hereof. The license agreement shall require the transfer
to Novartis of Regeneron's sales force dedicated to Detailing of the IL-1
Products. For the avoidance of doubt, if no Change of Control Notice is received
by Regeneron within ninety (90) days following a Change of Control, the
Agreement shall remain in full force and effect.

                  (b)      Regeneron will have the right to terminate this
Agreement on reasonable written notice upon a Change of Control of Novartis
where such Change of Control results in Novartis being owned or controlled by a
major Third Party pharmaceutical company with an annual turnover in excess of
$10 billion which is commercializing a Competing Product or has a Competing
Product in Phase III Clinical Trials at the time of such Change of Control.

                  (c)      Regeneron will have the right to terminate this
Agreement on a product-by-product basis with respect to the entire Territory,
for a particular IL-1 Product or on a country-by-country basis with respect to
any particular Co-Promotion Country, Co-Branding Country or Co-Marketing
Country, or in its entirety, upon written notice to Novartis, if Novartis shall
have breached any provision of Article 2 of the Registration Rights Agreement.

                  19.8 Effect of Termination for Material Breach, Insolvency,
Change of Control or Breach of Standstill Provisions.

                  (a)      Upon termination of this Agreement by Regeneron
pursuant to Section 19.5, 19.6 or 19.7(b) or (c), the provisions of Part A of
SCHEDULE 19 shall apply with respect to the each terminated IL-1 Product on a
country-by-country basis, if applicable, as if the terminated IL-1 Product is a
"Terminated Product", and except to the extent required by Novartis to fulfill
its obligations pursuant to Part A of SCHEDULE 19 (and upon the earlier of such
fulfillment or written notice from Regeneron that it will not require such
fulfillment, such licenses and rights, to the extent not previously terminated,
shall automatically terminate and revert to Regeneron), all licenses and rights
with respect to the terminated IL-1 Product granted to Novartis hereunder shall
automatically terminate and revert to Regeneron, on a country-by-country basis,
if applicable.

                  (b)      Upon termination of this Agreement by Novartis
pursuant to Section 19.5, 19.6 or 19.7(a), the provisions of Part B of SCHEDULE
19 (other than, with respect to any termination under Section 19.7(a), paragraph
2(a) of Part B of SCHEDULE 19) shall apply with respect to the each terminated
IL-1 Product on a country-by-country basis, if applicable, as if the terminated
IL-1 Product is a "Terminated Product", and except to the extent required by
Regeneron to fulfill its obligations pursuant to Part B of SCHEDULE 19 (and upon
the earlier of such fulfillment or written notice from Novartis that is will not
require such fulfillment, such licenses and rights, to the extent not previously
terminated, shall automatically terminate and revert to Novartis), all licenses
and rights with respect to the terminated IL-1 Product granted to Regeneron
hereunder shall automatically terminate and revert to Novartis, on a
country-by-country basis, if applicable.

                  19.9 Survival of Obligations. Except as otherwise provided in
this Article XIX, upon expiration or termination of this Agreement in whole or
in part, the rights and obligations of the Parties hereunder shall terminate to
the extent of such expiration or termination, and this Agreement shall cease to
be of further force or effect to the extent of such expiration or termination,
provided that notwithstanding any expiration or termination of

                                      -78-

<PAGE>

this Agreement, in whole or in part: (i) neither Novartis nor Regeneron shall be
relieved of any obligations of such Party arising prior to such expiration or
termination; (ii) subject to the provisions of this Article XIX (including
SCHEDULE 19 to the extent applicable), the obligations of the Parties with
respect to the protection and nondisclosure of Company Information and New
Information in accordance with Article XVI, as well as other provisions
(including, without limitation, Article XIX and SCHEDULE 19 to the extent
applicable and Sections 5.9 and 6.23) which by their nature are intended to
survive any such expiration or termination, shall survive and continue to be
enforceable, except as set forth in Section 6.22; and (iii) such expiration or
termination and this Article XIX shall be without prejudice to any rights or
remedies a party may have for breach of this Agreement, including, without
limitation, any breach of the provisions referred to in clause (ii) above.

                                   ARTICLE XX

                                  MISCELLANEOUS

                  20.1 Governing Law. This Agreement shall be governed by and
construed in accordance with the Laws of the State of New York, without regard
to conflict of laws principles.

                  20.2 Waiver. Waiver by a Party of a breach hereunder by the
other Party shall not be construed as a waiver of any succeeding breach of the
same or any other provision. No delay or omission by a Party in exercising or
availing itself of any right, power or privilege hereunder shall preclude the
later exercise of any such right, power or privilege by such Party. No waiver
shall be effective unless made in writing with specific reference to the
relevant provision(s) of this Agreement and signed by a duly authorized
representative of the Party granting the waiver.

                  20.3 Notices. All notices, instructions and other
communications hereunder or in connection herewith shall be in writing, shall be
sent to the address of the relevant Party set forth on SCHEDULE 20 attached
hereto and shall be (a) delivered personally, (b) sent by registered or
certified mail, return receipt requested, postage prepaid, (c) sent via a
reputable nationwide overnight courier service, or (d) sent by facsimile
transmission, with a confirmation copy to be sent by registered or certified
mail, return receipt requested, postage prepaid. Any such notice, instruction or
communication shall be deemed to have been delivered upon receipt if delivered
by hand, three (3) Business Days after it is sent by registered or certified
mail, return receipt requested, postage prepaid, one (1) Business Day after it
is sent via a reputable nationwide overnight courier service, or when
transmitted with electronic confirmation of receipt, if transmitted by facsimile
(if such transmission is on a Business Day; or otherwise, on the next Business
Day following such transmission). Either Party may change its address by giving
notice to the other Party in the manner provided above.

                  20.4 Entire Agreement. This Agreement (including Schedules),
together with the Stock Purchase Agreement and the Ancillary Agreements (when
executed), contains the complete understanding of the Parties with respect to
the subject matter hereof and thereof and supersedes all prior understandings
and writings relating to the subject matter hereof and thereof.

                  20.5 Amendments. No provision in this Agreement shall be
supplemented, deleted or amended except in a writing executed by Novartis and
Regeneron.

                                      -79-

<PAGE>

                  20.6 Headings. Headings in this Agreement are for convenience
of reference only and shall not be considered in construing this Agreement.

                  20.7 Severability. If, under applicable Laws, any provision
hereof is invalid or unenforceable, or otherwise directly or indirectly affects
the validity of any other material provision(s) of this Agreement ("Severed
Clause"), then, it is mutually agreed that this Agreement shall endure except
for the Severed Clause. The Parties shall consult and use their best efforts to
agree upon a valid and enforceable provision which shall be a reasonable
substitute for such Severed Clause in light of the intent of this Agreement.

                  20.8 Registration and Filing of the Agreement. To the extent,
if any, that a Party concludes in good faith that it is required to file or
register this Agreement or a notification thereof with any Governmental
Authority in accordance with applicable Laws, such Party may do so. The other
Party shall promptly cooperate in such filing or notification and shall promptly
execute all documents reasonably required in connection therewith. In such
situation, the Party making such filing or registration (and the other Party if
permitted under applicable Law) will request confidential treatment of sensitive
provisions of this Agreement, except to the extent the Party making such request
determines in good faith that such confidential treatment is not reasonably
likely to be granted under applicable Law. The Parties shall promptly inform
each other as to the activities or inquiries of any such Governmental Authority
relating to this Agreement, and shall promptly cooperate to respond to any
request for further information therefrom.

                  20.9 Assignment. Except as otherwise expressly provided
herein, neither this Agreement nor any of the rights or obligations hereunder
may be assigned by either Novartis or Regeneron without (a) the prior written
consent of Regeneron in the case of any assignment by Novartis or (b) the prior
written consent of Novartis in the case of an assignment by Regeneron, except in
each case to an Affiliate of the assigning Party or, subject to Section 19.7, to
any other party who acquires all or substantially all of the business of the
assigning Party by merger, sale or assets or otherwise, so long as such
Affiliate or other Party agrees in writing to be bound by the terms of this
Agreement. The assigning Party shall remain primarily liable hereunder
notwithstanding any such assignment. Any attempted assignment in violation
hereof shall be void.

                  20.10 Successors and Assigns. This Agreement shall be binding
upon and inure to the benefit of the Parties hereto and their respective
successors and permitted assigns.

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

                  20.12 Third-Party Beneficiaries. None of the provisions of
this Agreement, other than the sublicense to Novartis of rights under the Amgen
License Agreement provided for herein (the "Amgen Sublicense"), the penultimate
sentence of Section 4.5 and Section 13.4 (collectively, the "Amgen TPB
Provisions"), shall be for the benefit of or enforceable by any Third Party
including, without limitation, any creditor of any Party hereto. The Parties
acknowledge and agree that Amgen (i) shall be a direct Third Party beneficiary
of Novartis' obligations under the Amgen TPB Provisions, (ii) may enforce
Novartis' obligations under the Amgen TPB Provisions as if it were a party
hereto and (iii) shall have the right to seek remedies, including termination of
the Amgen Sublicense, in the event Novartis breaches its obligations under the
Amgen TPB Provisions. No Third Party (other than Amgen with

                                      -80-

<PAGE>

respect to Novartis' obligations under the Amgen TPB Provisions) shall obtain
any right under any provision of this Agreement or shall by reason of any such
provision make any claim in respect of any debt, liability or obligation (or
otherwise) against any Party hereto.

                  20.13 Relationship of the Parties. Each Party shall bear its
own costs incurred in the performance of its obligations hereunder without
charge or expense to the other except as expressly provided in this Agreement.
Neither Novartis nor Regeneron shall have any responsibility for the hiring,
termination or compensation of the other Party's employees or for any employee
compensation or benefits of the other Party's employees. No employee or
representative of a Party shall have any authority to bind or obligate the other
Party to this Agreement for any sum or in any manner whatsoever, or to create or
impose any contractual or other liability on the other Party without said
Party's approval. For all purposes, and notwithstanding any other provision of
this Agreement or any Ancillary Agreement to the contrary, Regeneron's legal
relationship under this Agreement to Novartis, and Novartis' legal relationship
under this Agreement to Regeneron, shall be that of independent contractor.
Nothing in this Agreement shall be construed to establish a relationship of
partners or joint ventures between the Parties or any of their respective
Affiliates.

                  20.14 Limitation of Damages. IN NO EVENT SHALL REGENERON OR
NOVARTIS BE LIABLE FOR SPECIAL, INDIRECT, INCIDENTAL OR CONSEQUENTIAL DAMAGES
(INCLUDING, WITHOUT LIMITATION, LOSS OF PROFITS) SUFFERED BY THE OTHER PARTY,
EXCEPT TO THE EXTENT ANY SUCH DAMAGES ARE PAID TO A THIRD PARTY AS PART OF A
THIRD-PARTY CLAIM.

                  20.15 Non-Solicitation. The Parties recognize that each Party
has a substantial interest in preserving and maintaining confidential its
Company Information and New Information provided to the other Party hereunder.
Each Party recognizes that certain of the other Party's employees, including
those engaged in the Development, Co-Promotion, Co-Branding or Co-Marketing of
IL-1 Products, may have access to such Company Information and New Information
of the other Party. The Parties therefore agree, during the Term and for a
period of two years thereafter, not to solicit or otherwise induce or attempt to
induce for purposes of employment, any employees from the other Party involved
in the manufacture, Development, Co-Promotion, Co-Branding or Co-Marketing of
any IL-1 Product.

                  20.16 Hardship. If as a result of unforeseen events or
developments relating to the subject matter of this Agreement, the performance
of this Agreement shall cause inequitable economic hardship for one Party which
runs counter to the objectives of this Agreement and which the other Party
cannot reasonably and in good faith expect the first Party to bear unrelieved,
the Parties will meet and seek in good faith to find equitable means of amending
this Agreement to reestablish a fair and reasonable economic balance under this
Agreement between the Parties hereto.

                                      -81-

<PAGE>

                                                                   Exhibit 10.23

         IN WITNESS WHEREOF, Novartis and Regeneron have caused this Agreement
to be executed by their duly authorized representatives as of the day and year
first above written.

                                  NOVARTIS PHARMA AG

                                  By /s/ Subhanu Saxena
                                     -------------------------------------------
                                     Name: Subhanu Saxena
                                     Title: Head of Global Business
                                     Development and Licensing

                                  By /s/ Kim Urdahl
                                     -------------------------------------------
                                     Name: Kim Urdahl
                                     Title: Head of Legal, Primary Care

                                  REGENERON PHARMACEUTICALS, INC.

                                  By /s/ Murray Goldberg
                                     -------------------------------------------
                                     Name: Mr. Murray Goldberg
                                     Title: Senior Vice President, Finance and
                                     Administration

                    For the purposes of Section 9.4(a) only:

                                   NOVARTIS PHARMACEUTICALS CORP.

                                   By /s/ Gary Rosenthal
                                      ------------------------------------------
                                      Name: Mr. Gary Rosenthal
                                      Title: Vice President, Finance and
                                      Administration

<PAGE>

                                                                      SCHEDULE 1

                              Target Profit Splits

         Funds flow mechanisms with respect to Co-Commercialization Countries
shall be designed to achieve the following Target Profit Splits (for the
avoidance of doubt, the Target Profit Splits shall apply independent of the
Detailing effort provided by either Party, such that, for example, in the case
of the example set forth under paragraph 1 below, in NAFTA if Regeneron provided
none of the Detailing efforts, it will still be entitled to 50% of the Net
Profits):

                  1.       Trap-1. Net Profits (excluding Development Costs -
see example below) on sales of the Trap-1 Product in the Co-Commercialization
Countries in the Trap-1 Territory to be shared as set forth below:

                  (a)      NAFTA - 50% to Novartis, 50% to Regeneron

                  (b)      Europe - 50% to Novartis, 50% to Regeneron

                  (c)      Rest of World - 75% to Novartis, 25% to Regeneron.

         An example of this would be (with respect to, e.g., the United States):

<TABLE>
<CAPTION>
                                                                NVS         RGEN
                                                                50%          50%
<S>                                             <C>            <C>          <C>
Net Sales                                       100.0
COGS                                            (10.0)
                                                -----
                           Gross Margin          90.0           45.0         45.0
Expenses                                        (50.0)         (25.0)       (25.0)
                                                -----
          Net Profit (Before Dev. Costs)         40.0           20.0         20.0
Post-Phase IIB
Development Costs                               (10.0)          (5.0)        (5.0)
                                                -----

                           Net Profit            30.0           15.0         15.0
                                                =====           ====         ====
</TABLE>

         2.       IL-1 Antibody. Net Profits (including Development Costs - see
example below) on sales of the IL-1 Antibody Product in the Co-Commercialization
Countries in the IL-1 Antibody Territory to be shared 55% to Novartis, 45% to
Regeneron. An example of this would be:

<TABLE>
<CAPTION>
                                                                NVS         RGEN
                                                                55%          45%
<S>                                                <C>         <C>         <C>
Net Sales                                          100.0
COGS                                               (10.0)
                                                   -----
                             Gross Margin           90.0        49.5        40.5

Expenses                                           (50.0)      (27.5)      (22.5)
                                                   -----       -----------------
             Net Profit (Before Dev. Costs)         40.0        22.0        18.0

Post-Phase IIB
Development Costs                                  (10.0)       (5.5)       (4.5)
                                                   -----       -----------------
                                Net Profit          30.0        16.5        13.5
                                                   =====       =================
</TABLE>

<PAGE>

                                                                      Schedule 1
                                                                          Page 2

         3.       Trap-2. Net Profits (including Development Costs - see example
below) on sales of the Trap-2 Product in the Co-Commercialization Countries in
the Trap-2 Territory to be shared as set forth below:

                  (a)      NAFTA - 50% to Novartis, 50% to Regeneron

                  (b)      Europe - 50% to Novartis, 50% to Regeneron

                  (c)      Rest of World - 75% to Novartis, 25% to Regeneron.

         An example of this would be (with respect to, e.g., the United States):

<TABLE>
<CAPTION>
                                                                  NVS            RGEN
                                                                  50%             50%
<S>                                                <C>           <C>            <C>
Net Sales                                          100.0
COGS                                               (10.0)
                                                   -----
                                Gross Margin        90.0          45.0           45.0
Expenses                                           (50.0)        (25.0)         (25.0)
                                                   -----
              Net Profit (Before Dev. Costs)        40.0          20.0           20.0
Post-Phase IIB
Development Costs                                  (10.0)        ( 5.0)         ( 5.0)
                                                   -----         -----          -----
                                  Net Profit        30.0          15.0           15.0
                                                   =====         =====          =====
</TABLE>

<PAGE>

                                                                      SCHEDULE 2

                         Proportion of Detailing Efforts

                              (See Section 6.10(a))

         1.       Trap-1.

<TABLE>
<CAPTION>
----------------------------------------------
                     Novartis       Regeneron
                     --------       ---------
   Region           Percentage      Percentage
   ------           ----------      ----------
----------------------------------------------
<S>                 <C>             <C>
NAFTA                 [****]         [*****]
----------------------------------------------
Europe                [****]         [*****]
----------------------------------------------
Rest of World         [****]         [*****]
----------------------------------------------
</TABLE>

         2.       IL-1 Antibody.

<TABLE>
<CAPTION>
----------------------------------------------
                     Novartis       Regeneron
                     --------       ---------
   Region           Percentage      Percentage
   ------           ----------      ----------
----------------------------------------------
<S>                 <C>             <C>
NAFTA                 [****]         [*****]
----------------------------------------------
</TABLE>

         3.       Trap-2.

<TABLE>
<CAPTION>
----------------------------------------------
                     Novartis       Regeneron
                     --------       ---------
   Region           Percentage      Percentage
   ------           ----------      ----------
----------------------------------------------
<S>                 <C>             <C>
NAFTA                [****]          [****]
----------------------------------------------
Europe               [****]          [****]
----------------------------------------------
Rest of World        [****]          [****]
----------------------------------------------
</TABLE>

<PAGE>

                                                                      SCHEDULE 3

                                     Royalty

                                (see Section 9.3)

             [****************************************************]

<PAGE>

                                                                      SCHEDULE 4

                            Shared Development Costs

                              (see Section 9.2(a))

         1.       Trap-1.

                  (a)      Commencing in 2004, Novartis will be responsible for
         one hundred percent (100%) of aggregate Pre-Phase III Development Costs
         for the Trap-1 Product in the Co-Commercialization Countries in the
         Trap-1 Territory.

                  (b)      Other than as set forth in paragraph (a) above, the
         Parties will each be responsible for fifty percent (50%) of the
         aggregate Development Costs for the Trap-1 Product in the
         Co-Commercialization Countries in the Trap-1 Territory.

                  (c)      In the event that a Party has incurred less than its
         applicable percentage share of such Development Costs for an applicable
         calendar quarter, then, pursuant to Section 9.2(a) such Party shall
         reimburse the other Party in such amount as is necessary to result in
         each Party bearing its applicable share of such Development Costs for
         such calendar quarter.

                  (d)      For avoidance of doubt, commencing in 2004, if there
         are Phase II Development Costs for the Trap-1 Product at the same time
         that there are Phase III Development Costs for the Trap-1 Product,
         Novartis will be responsible for 100% of the Phase II Development Costs
         and the Parties will share equally in the Phase III Development Costs.

         2.       IL-1 Antibody. Novartis shall be responsible for an amount
equal to the product of the aggregate Development Costs for the IL-1 Antibody
Product in the Co-Commercialization Countries for NAFTA for the relevant
calendar quarter multiplied by fifty-five percent (55%), and Regeneron shall be
responsible for an amount equal to the product of the aggregate Development
Costs for the IL-1 Antibody Product in the Co-Commercialization Countries in
NAFTA for the relevant calendar quarter multiplied by forty-five percent (45%).
In the event that a Party has incurred less than its applicable percentage share
of such Development Costs for an applicable calendar quarter, then, pursuant to
Section 9.2(a), such Party shall reimburse the other Party in such amount as is
necessary to result in each Party bearing its applicable share of such
Development Costs for such calendar quarter.

         3.       Trap-2. The Parties will each be responsible for fifty percent
(50%) of the aggregate Development Costs for the Trap-2 Product in the
Co-Commercialization Countries in the Trap-2 Territory. In the event that a
Party has incurred less than its applicable percentage share of such Development
Costs for an applicable calendar quarter, then, pursuant to Section 9.2(a), such
Party shall reimburse the other Party in such amount as is necessary to result
in each Party bearing its applicable share of such Development Costs for such
calendar quarter.

<PAGE>

                                                                      SCHEDULE 5

                           Failure to Perform Details

                             (see Section 6.10 (e))

If a Party fails to actually perform committed Details, then the penalty will be
calculated as a multiple of the costs associated with the missed details. The
multiplying factor is calculated as follows:

[*********************************************************************]

The Party which has failed to perform committed Details will have the
opportunity to cure the shortfall in the next quarter and thereby avoid or
reduce, as applicable, the penalty that would otherwise apply.

<PAGE>

                                                                      SCHEDULE 6

                               Milestone Payments

                              (see Section 9.4(b))

         1.       Trap-1.

         Upon the first occurrence of each of the events set forth below,
Novartis shall pay to Regeneron the corresponding amount set forth below:

<TABLE>
<CAPTION>
--------------------------------------------------------
                                            Milestone
                                            ---------
Milestone Event                             Payment
---------------                             -------
--------------------------------------------------------
<S>                                         <C>
[****************************]              [********]
--------------------------------------------------------
[****************************]              [********]
--------------------------------------------------------
[****************************]              [**********]
--------------------------------------------------------
[***************************]               [**********]
--------------------------------------------------------
</TABLE>

         For the avoidance of doubt, each of the above milestones will be
payable only once, but may occur in the same year.

         2.       IL-1 Antibody.

         Upon the first occurrence of each of the events set forth below,
Regeneron shall pay to Novartis the corresponding amount set forth below:

<TABLE>
<CAPTION>
--------------------------------------------------------
                                            Milestone
                                            ---------
Milestone Event                             Payment
---------------                             -------
--------------------------------------------------------
<S>                                         <C>
[****************************]              [*******]
--------------------------------------------------------
[***************************]               [********]
--------------------------------------------------------
[***************************]               [********]
--------------------------------------------------------
</TABLE>

         For the avoidance of doubt, each of the above milestones will be
payable only once, but may occur in the same year.

         3.       Trap-2.

         Upon the first occurrence of each of the events set forth below,
Novartis shall pay to Regeneron the corresponding amount set forth below:

<TABLE>
<CAPTION>
--------------------------------------------------------
                                            Milestone
                                            ---------
Milestone Event                             Payment
---------------                             -------
--------------------------------------------------------
<S>                                         <C>
[***********************]                   [**********]
--------------------------------------------------------
</TABLE>

<PAGE>

                                                                      Schedule 6
                                                                          Page 2

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

         For the avoidance of doubt, each of the above milestones will be
payable only once, but may occur in the same year.

<PAGE>

                                                                      SCHEDULE 7
                                                                          PAGE 1

                         PRINCIPLES IN DETERMINING COGS:

                              (SEE SECTION 8.2(a))

[********************************************************
*********************************************************
*********************************************************]

Non-binding example of the cost pricing details for the processing of Trap-1

[**********************************************************]

<PAGE>

                                                                      SCHEDULE 8

                          Preliminary Development Plan

                     IL-1 TRAP PRELIMINARY DEVELOPMENT PLAN

[*******************************************************************************
********************************************************************************
********************************************************************************
*******************************************************************************]

<PAGE>

                                                                      SCHEDULE 9

                    First Consolidated Co-Development Budget

($ IN MM)

                             [*  *  *  *  *  *  *]
<PAGE>

IL-1 TRAP - R&D SUPPORT - PRELIMINARY OUTSIDE EXPENSES

($ IN MM)

                             [*  *  *  *  *  *  *]
<PAGE>

                                                                     SCHEDULE 10

                            Non-Distributor Countries

                         (See Sections 4.1, 4.3 and 6.1)

[*****************]

<PAGE>

                                                                     SCHEDULE 11

   Regulatory Tasks To Be Conducted By Novartis in U.S. For Trap-1 and Trap-2

                           (See Sections 7.1 and 7.6)

         Preparation and formatting of the BLA via electronic submission

         Provision of electronic study templates and documents

         Quality check on all documents/data for submission

         Quality check on datasets prior to final study report

         Coordination of pharmacoviligance activities and submission of reports
via electronic submission, if possible

<PAGE>

                                                                     SCHEDULE 12

           Procedures for Adverse Event and Other Safety Data Exchange
                           Notification and Reporting

                                 [TO BE ADDED.]

<PAGE>

                                                                     SCHEDULE 13

                                Existing Licenses

         [******************************************]

<PAGE>

                                                                 SCHEDULES 14-18

                             [INTENTIONALLY OMITTED]

<PAGE>

                                                                     Schedule 19
                                                                          Page 1

                                                                     SCHEDULE 19

                             Transition Arrangements

         The rights and obligations set forth in this SCHEDULE 19 shall apply
only to the extent of the applicable termination of this Agreement, and
accordingly such rights and obligations shall apply only with respect to the
Terminated Product(s) as to which, in the countries in which, the Agreement has
been terminated.

         PART A - TRANSITION TO REGENERON

         1.       Novartis shall promptly collect and return, and cause its
Affiliates and sublicensees to collect and return, to Regeneron or, at
Regeneron's request, destroy, all documents provided by Regeneron and containing
Company Information or New Information of Regeneron relating to the Terminated
Product(s) in any countries in which the Agreement has been terminated, and
shall immediately cease, and cause its Affiliates and sublicensees to cease, all
further use of any such Company Information or New Information of Regeneron with
respect to the Terminated Products in any countries in which the Agreement has
been terminated;

         2.       Novartis shall use Commercially Reasonable Efforts to provide
all cooperation and assistance reasonably requested by Regeneron to enable
Regeneron (or its nominee) to assume with as little disruption as reasonably
possible, the continued Development and/or Commercialization of Terminated
Product(s) in all countries in which the Agreement has been terminated. Such
cooperation and assistance shall be provided in a prompt and timely manner
(having regard to the nature of the cooperation or assistance requested) and
shall include, without limitation, the following:

                  (a)      Regeneron shall have an exclusive license (which
         shall include the right to grant sublicenses) from Novartis under
         Novartis Patent Rights and Novartis Know-How existing at the effective
         date of termination to Develop, make, have made, use, import, offer to
         sell and sell the Terminated Products in the applicable countries. Such
         license shall be fully paid-up and royalty-free if the Terminated
         Product is the Trap-1 Product or the Trap-2 Product, and, if the
         Terminated Product is the IL-1 Antibody Product, such license shall be
         subject to a royalty unless the Agreement was terminated with respect
         to the IL-1 Antibody Product by Regeneron pursuant to Section 19.4. The
         amount of such royalty shall be determined by the mutual agreement of
         the Parties after good faith negotiations and shall be dependent upon
         (i) the stage of Development and/or Commercialization of the Terminated
         Product(s); (ii) the anticipated future profitability of the Terminated
         Product(s) and (iii) the efforts and expenses to be incurred by the
         terminating Party in Development and Commercializing the Terminated
         Product(s). If the Parties are unable to reach mutual agreement thereon
         within three (3) months after the effective date of termination, the
         matter shall be submitted for arbitration in accordance with the terms
         of Article X of this Agreement.

                  (b)      Novartis shall transfer and assign to Regeneron (or
         its nominee) all Approvals and regulatory filings (including
         Registration Filings) in the applicable countries made or obtained by
         Novartis or its Affiliates or any of its sublicensees to the extent
         relating to Terminated Product(s) (other than Approvals for
         manufacturing facilities).

<PAGE>

                                                                     Schedule 19
                                                                          Page 2

                  (c)      Novartis shall assign and transfer to Regeneron (or
         its nominee) Novartis' entire right, title and interest in and to all
         Product Trademarks to the extent relating to Terminated Product(s) in
         the applicable countries and to any domain names containing such
         Product Trademarks.

                  (d)      Novartis shall provide to Regeneron (or its nominee)
         a copy (or originals to the extent required by any Regulatory Authority
         in connection with the manufacture, Development or Commercialization of
         Terminated Product(s) in all countries in which the Agreement has been
         terminated of all information (including any Novartis Company
         Information and/or New Information) in its possession or under its
         control to the extent relating to any Terminated Product(s) in all
         countries in which the Agreement has been terminated, including,
         without limitation, all information contained in the regulatory and/or
         safety databases, all in the format then currently maintained by
         Novartis, or such other format as may be reasonably requested by
         Regeneron and notwithstanding any provision of Article XVI, Regeneron
         shall be entitled to use and disclose any such information (including
         any such Novartis Company Information and/or New Information) in
         connection with the manufacture, Development, Commercialization,
         production of any Terminated Product(s) in the applicable countries.

                  (e)      To the extent the Terminated Product is being
         manufactured by a Third Party as of the date notice of termination is
         given, then Novartis shall assign to Regeneron Novartis' rights with
         respect to the Terminated Product under its agreement with the Third
         Party manufacturer in so far as they relate to any country which is the
         subject of the termination.

                  (f)      Novartis shall assign to Regeneron any applicable
         sublicenses to the extent related to Terminated Products and/or
         subcontracts relating to significant services to be performed by Third
         Parties to the extent related to manufacture, Development or
         Commercialization of Terminated Products in the applicable countries,
         as reasonably requested by Regeneron.

                  (g)      Without limitation of Novartis' other rights
         obligations under this Part A of SCHEDULE 19, (i) In the event that
         Novartis or any of its Affiliates is responsible for manufacturing any
         Terminated Product as of the date notice of termination is given,
         Novartis will take the actions required by subparagraph (g)(ii) below,
         including, for a period and at the price described in paragraph (g)(ii)
         below, supplying Regeneron with Clinical Supply Requirements and/or
         Commercial Requirements, as applicable.

                  (ii) (A) In the event notice of termination is given prior to
         Launch of the Terminated Product(s) and Novartis's manufacturing
         facility or facilities to manufacture such Terminated Product which is
         referred to in Section 8.2(a) of the Agreement (the "Novartis'
         Manufacturing Facilities") has (have) not yet been completed, Novartis
         will use Commercially Reasonable Efforts to complete the construction
         and build-out of the Novartis Manufacturing Facilities as expeditiously
         as possible, and will supply Regeneron with Clinical Supply
         Requirements and/or Commercial Requirements, as applicable, of finished
         and packaged Terminated Product(s) for use in any country which is the
         subject of the termination, at the same price, and on such other terms
         and conditions on, which Novartis was supplying, or in the absence of
         termination, would have been required to supply such finished and

<PAGE>

                                                                     Schedule 19
                                                                          Page 3

         packaged Terminated Product(s), through the second anniversary of the
         Launch of such Terminated Product(s).

                  (B) In the event notice of termination is given prior to
         Launch of the Terminated Product(s) and the Novartis Manufacturing
         Facilities have been completed, Novartis will supply Regeneron with
         Clinical Supply Requirements and/or Commercial Requirements, as
         applicable, of finished and packaged Terminated Products for use in any
         country which is the subject of the termination on the same price and
         other terms and conditions, and for the same period as provided in
         subparagraph (ii)(A) above.

                  (C) In the event notice of termination is given after Launch
         of the Terminated Product(s), Novartis will supply Regeneron with
         Commercial Requirements of finished and packaged Terminated Product(s)
         for use in any country which is the subject of the termination at same
         price and other terms and conditions as provided in subparagraph
         (ii)(A) above, until the second anniversary of the effective date of
         termination, and if Regeneron so requests, for one additional year,
         provided that the price and other terms and conditions on, which such
         Terminated Products will be supplied for such additional year shall be
         reasonable and customary as determined by good faith negotiations
         between the Parties.

         3.       Without limitation of the generality of the foregoing, the
Parties shall use Commercially Reasonable Efforts to complete the transition of
the manufacture, Co-Development and Co-Commercialization of any Terminated
Products hereunder to Development, Commercialization of such Terminated Products
for use in any country which is the subject of the termination solely by
Regeneron or its designees as soon as is reasonably possible.

         4.       For the avoidance of doubt, except as set forth in paragraph
2(a) above, Regeneron shall not be required to provide Novartis any
consideration in exchange for the licenses or other rights granted to it
pursuant to the provisions of this Part A of SCHEDULE 19; provided, however,
that Regeneron shall be solely responsible for paying any royalties, fees or
other consideration that Novartis may be obligated to pay to a Third Party in
respect of any such transfer or sublicense to Regeneron of such licenses or
other rights.

         PART B - TRANSITION TO NOVARTIS

         1.       Regeneron shall promptly collect and return, and cause its
Affiliates and sublicensees to collect and return, to Novartis or, at Novartis'
request, destroy, all documents provided by Novartis and containing Company
Information or New Information of Novartis relating to the Terminated Product(s)
in any countries in which the Agreement has been terminated, and shall
immediately cease, and cause its Affiliates and sublicensees to cease, all
further use of any such Company Information or New Information of Novartis with
respect to the Terminated Product(s) in any countries in which the Agreement has
been terminated;

         2.       Regeneron shall use Commercially Reasonable Efforts to provide
all cooperation and assistance reasonably requested by Novartis to enable
Novartis (or its nominee) to assume with as little disruption as reasonably
possible, the continued Development and/or Commercialization of Terminated
Product(s) in all countries in which the Agreement has been terminated. Such
cooperation and assistance shall be provided in a

<PAGE>

                                                                     Schedule 19
                                                                          Page 4

prompt and timely manner (having regard to the nature of the cooperation or
assistance requested) and shall include, without limitation, the following:

                  (a)      Novartis shall have an exclusive license (which shall
         include the right to grant sublicenses) from Regeneron under Regeneron
         Patent Rights and Regeneron Know-How existing at the effective date of
         termination to Develop, make, have made, use, import, offer to sell and
         sell the Terminated Products in the applicable countries. Such license
         shall be fully paid-up and royalty-free if the Terminated Product is
         the IL-1 Antibody Product, and, if the Terminated Product is the Trap-1
         Product or the Trap-2 Product, such license shall be subject to a
         royalty, unless the Agreement was terminated with respect to the Trap-1
         Product or Trap-2 Product, as applicable, by Novartis pursuant to
         Section 19.4. The amount of such royalty shall be determined by the
         mutual agreement of the Parties after good faith negotiations and shall
         be dependent upon (i) the stage of Development and/or Commercialization
         of the Terminated Product(s); (ii) the anticipated future profitability
         of the Terminated Product(s) and (iii) the efforts and expenses to be
         incurred by the terminating Party in Developing and Commercializing the
         Terminated Product(s). If the Parties are unable to reach mutual
         agreement thereon within three (3) months after the effective date of
         termination, the matter shall be submitted for arbitration in
         accordance with the terms of Article X of this Agreement.

                  (b)      Regeneron shall transfer and assign to Novartis (or
         its nominee) all Approvals and regulatory filings (including
         Registration Filings) in the applicable countries made or obtained by
         Regeneron or its Affiliates or any of its sublicensees to the extent
         relating to Terminated Product(s) (other than Approvals for
         manufacturing facilities).

                  (c)      Regeneron shall assign and transfer to Novartis (or
         its nominee) Regeneron's entire right, title and interest in and to all
         Product Trademarks to the extent relating to Terminated Product(s) in
         the applicable countries, and to any domain names containing such
         Product Trademarks.

                  (d)      Regeneron shall provide to Novartis (or its nominee)
         a copy (or originals to the extent required by any Regulatory Authority
         in connection with the manufacture, Development or Commercialization of
         Terminated Product(s) of all information (including any Regeneron
         Company Information and/or New Information) in its possession or under
         its control to the extent relating to any Terminated Product(s) in all
         countries in which the Agreement has been terminated, including,
         without limitation, all information contained in the regulatory and/or
         safety databases, all in the format then currently maintained by
         Regeneron, and notwithstanding any provision of Article XVI, Novartis
         shall be entitled to use and disclose any such information (including
         any such Regeneron Company Information and/or New Information) in
         connection with the manufacture, Development or Commercialization of
         any Terminated Product(s) in the applicable countries.

                  (e)      To the extent Terminated Product is being
         manufactured by a Third Party under contract with or from Regeneron as
         of the date notice of termination is given, then Regeneron shall assign
         to Novartis Regeneron's rights with respect to the Terminated Product
         under such agreement with the Third Party manufacturer as far as they
         relate to any country which is the subject of the termination.

<PAGE>

                                                                     Schedule 19
                                                                          Page 5

                  (f)      Regeneron shall assign to Novartis any applicable
         sublicenses to the extent related to Terminated Products and/or
         subcontracts relating to significant services to be performed by Third
         Parties to the extent related to manufacture, Development or
         Commercialization of Terminated Products in the applicable countries,
         as reasonably requested by Novartis.

                  (g)      In the event that Regeneron or any of its Affiliates
         is responsible for manufacturing any Terminated Product as of the date
         of termination, Regeneron will, for a period not to exceed two (2)
         years following such date, supply Novartis with sufficient quantities
         of such Terminated Product to enable Novartis to continue the
         Development of such Terminated Product in accordance with the scope of
         the Consolidated Co-Development Plan as at the date of such
         termination. Regeneron shall supply such Terminated Product to Novartis
         and its Affiliates at the same price, and on such other terms and
         conditions on, which Regeneron was supplying such Terminated Product
         pursuant to this Agreement.

         3.       Without limitation of the generality of the foregoing, the
Parties shall use Commercially Reasonable Efforts to complete the transition of
the manufacture, Co-Development and Co-Commercialization of any Terminated
Products hereunder to manufacture, Development and Commercialization solely by
Novartis, its Affiliates and/or designees as soon as is reasonably possible.

         4.       For the avoidance of doubt, except as set forth in paragraph
2(a) above, Novartis shall not be required to provide Regeneron any
consideration in exchange for the licenses or other rights granted to it
pursuant to the provisions of this Part B of SCHEDULE 19; provided, however,
that Novartis shall be solely responsible for paying any royalties, fees or
other consideration that Regeneron may be obligated to pay to a Third Party in
respect of any such transfer or sublicense to Novartis of such licenses or other
rights.

<PAGE>

                                                                     SCHEDULE 20

                                     NOTICES

         (a)      If to Novartis:

                  Novartis Pharma AG
                  CH-4002 Basel, Switzerland
                  Attention: Head of Business Development & Licensing
                  Copy: Head of Legal Services

         (b)      If to Regeneron:

                  Regeneron Pharmaceuticals, Inc.
                  777 Old Saw Mill River Road
                  Tarrytown, New York 10591
                  U.S.A.
                  Attention: President
                  Copy: General Counsel

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00052-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00052-of-00352.parquet"}]]