<PAGE>

                                                                   EXHIBIT 10.28

               COLLABORATIVE DEVELOPMENT AND MARKETING AGREEMENT

     This Collaborative Development and Marketing Agreement (this "Agreement")
                                                                   ---------
is made as of the Effective Date defined below by and between ZymoGenetics,
Inc., a Washington corporation having its principal place of business at 1201
Eastlake Avenue East, Seattle, Washington 98102 ("ZGI"), and Ares Trading S.A.,
                                                  ---
a Swiss corporation having offices at Chateau de Vaumarcus, 2028 Vaumarcus,
Switzerland ("Serono"), with respect to the following recitals:
              ------

     A.  ZGI is engaged generally in the research and development of
biopharmaceutical products and has developed and acquired certain intellectual
property relating to certain receptors that play a role in one or more
autoimmune and/or other diseases.

     B.  Serono is engaged generally in the research, development, manufacture,
marketing, distribution, and sales of biopharmaceutical products.

     C.  Serono and ZGI wish collaboratively to fund and conduct activities
focused primarily on discovery and development of one or more new products
related to such receptors, securing regulatory approval for marketing thereof,
and marketing and co-promotion thereof, in North America and elsewhere
worldwide.

     THEREFORE, the parties hereby agree as follows:

                                  ARTICLE ONE

                          Definitions and Terminology

     In addition to other terms defined elsewhere in this Agreement, the
following words and phrases shall have the following stated or referenced
meanings:

     1.1  "Affiliate" means any company, joint venture, partnership, or other
           ---------
business entity that controls, is controlled by, or is under common control with
a party hereto.  A business entity shall be deemed to control another business
entity if it possesses, directly or indirectly, the power to order or cause the
direction, management and policies of such other business entity through the
ownership of over fifty percent (50%) of the voting securities of that entity.

     1.2  "Allocated Net Sales" means the [ * ] invoiced by any of Serono or its
           -------------------
Affiliates or Sublicensees for the sale of [ * ], less [ * ] described in [ * ]
multiplied by the [ * ], where [ * ] is [ * ] of [ * ] of the [ * ] incorporated
into such [ * ] when sold [ * ] in the [ * ], and [ * ] is the [ * ] of the
[ * ]. If the [ * ] incorporated into such [ * ] is not [ * ] in [ * ] in the
[ * ], the [ * ] of the [ * ], for purposes of [ * ], shall be determined by
[ * ] the [ * ] by [ * ], [ * ], where [ * ] is the [ * ] of [ * ] of the [ * ]
when sold [ * ] in [ * ] in the [ * ] and [ * ] is the [ * ] of the [ * ]. If
the [ * ] of [ * ] the [ * ] the [ * ] when [ * ] in [ * ] in the [ * ] can be
determined, the [ * ] of the [ * ], for purposes of [ * ], shall be [ * ] by
[ * ]. The [ * ] that shall be used as [ * ] of the [ * ]

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -1-
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for a particular [ * ] as described in this section shall be determined [ * ],
during [ * ], and such [ * ] shall be used for such purpose during all
applicable [ * ] for that [ * ]. The [ * ] of a [ * ] shall be calculated using
data from sales made during the entire immediately preceding calendar year.

     1.3   "Alternative Ligand" means any [ * ] other than [ * ] that is or
            ------------------
becomes [ * ] (based on at least preliminary data) to act [ * ].

     1.4   "Alternative Receptor" means any [ * ] other than [ * ] that is or
            --------------------
becomes [ * ] (based on at least preliminary data) to act on [ * ] or [ * ].

     1.5   "Background Technology" means the Serono Background Technology and
            ---------------------
the ZGI Background Technology.

     1.6   "BCMA" means the receptor described in International Patent
            ----
Application [ * ].

     1.7   "Calendar Quarter" means each three (3) month period commencing
            ----------------
January 1, April 1, July 1, or October 1.

     1.8   "CEO" means the Chief Executive Officer of each party, except that in
            ---
the case of Serono it shall mean the Chief Executive Officer of S.A.

     1.9   "cGMP" means the legal and regulatory requirements established from
            ----
time to time by the FDA for current Good Manufacturing Practices for human
pharmaceutical products and such standards of good manufacturing practice as are
required by other Regulatory Authorities, to the extent such standards are not
less stringent than cGMP standards promulgated by the FDA.

     1.10  "Combination Product" means [ * ] that comprises a [ * ] that are not
            -------------------
Licensed Products.

     1.11  "Commercial Use" means use for a revenue-generating purpose,
            --------------
inclusive of samples intended for promotional purposes, and does not mean use
for purposes such as research, development or clinical testing conducted in
conjunction with obtaining Regulatory Approval.

     1.12  "Commercialization Contacts" means the persons appointed by each
            --------------------------
party to serve as contact persons between the parties from time to time in
relation to a Commercialization Team, if any.  Subject to Section 3.3, the
parties' initial Commercialization Contacts shall be designated, respectively,
by each party within thirty (30) days following Initiation of Phase III Clinical
Trials for a Licensed Product.  Each party shall promptly notify the other party
of any substitution of other personnel as its Commercialization Contact.

     1.13  "Commercialization Plan and Budget" means the detailed written
            ---------------------------------
description of approved promotional, co-promotional, marketing, and sales
activities with respect to a Licensed Product in North America, together with a
budget therefor, approved or to be approved by Steering Committee Action.

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -2-
<PAGE>

     1.14  "Commercialization Team" means a committee to be formed as provided
            ----------------------
in Section 3.3, two (2) members of which shall be the Commercialization
Contacts.  The number of members of the Commercialization Team may be increased
from time to time by Steering Committee Action.  While the parties need not be
equally represented in number of members on the Commercialization Team, the
Commercialization Team will be co-led by the two (2) Commercialization Contacts.

     1.15  "Contractor" means a Third Party or an Affiliate to which a party
            ----------
desires to subcontract any portion of its Development Tasks or North American
Co-Promotion Tasks, to the extent permitted pursuant to this Agreement.  For
purposes of this Agreement, payments to a Contractor that is an Affiliate of the
payor shall be limited to the applicable costs described in Exhibit 1.20 or
Exhibit 1.46.

     1.16  "Controls" and "Controlled" mean that the entity referenced has the
            --------       ----------
ability to exploit and to license or sublicense the right to exploit the
referenced technology or rights, as provided for in this Agreement, without
(assuming the timely payment of all applicable royalties) violating any
intellectual property rights of a Third Party or the terms of any agreement or
other arrangement with any Third Party.

     1.17  "Declined Product" means any Licensed Product, which, at the time of
            ----------------
the grant of a sublicense pursuant to Section 10.6, is not subject to a
Development Project.

     1.18  "Declined Product Sublicensing Revenues" means [ * ] of whatever type
            --------------------------------------
or character [ * ] including any and all [ * ] but excluding that portion of any
such consideration [ * ].  If and to the extent such [ * ] includes [ * ] shall
include [ * ].

     1.19  "Derivative" means a composition or material that is derived [ * ] in
            ----------
one or more steps from any compositions or materials that are part of the [ * ]
and that has or is intended to have [ * ].  Notwithstanding the above[ * ] will
not be considered Derivatives.

     1.20  "Development Costs" means those costs incurred or otherwise borne or
            -----------------
to be borne by the parties or their Affiliates or Contractors in accordance with
the Development Plan and Budget and in the course of the Development Project, as
more fully described in Exhibit 1.20.  The Development Costs shall be accounted
for by each party in accordance with the cost accounting principles described in
Exhibit 1.20.

     1.21  "Development Plan and Budget" means the detailed written description
            ---------------------------
of the parties' and their Contractors' respective Development Tasks, together
with a budget therefor, approved or to be approved by Steering Committee Action.

     1.22  "Development Project" means, as to any Licensed Product, the project
            -------------------
contemplated under this Agreement and directed at the development, manufacture,
testing and registration of such Licensed Product in the Territory excluding
Japan.  A Development Project for a particular Licensed Product shall end either
upon the Regulatory Approval for such Licensed Product, upon termination of the
post-launch clinical studies or market surveillance for such Licensed Product as
described in Section 1.24(g) or otherwise as provided in Section 1.23.

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -3-
<PAGE>

     1.23  "Development Project Term" means the period from the Effective Date
            ------------------------
until the date when the last Development Project in effect for any Licensed
Product has terminated and the last of any development projects for the Licensed
Product in Japan has terminated; provided, however, that if no Licensed Product
has received Regulatory Approval on or before the fifteenth anniversary of the
Effective Date, the "Development Project Term" shall end at such anniversary;
provided, however, that:  (a) any Development Project, or development project
for the Licensed Product in Japan, then in effect shall continue until one or
more parties terminates its roles and responsibilities thereunder either
pursuant to Section 4.8 or otherwise, and the Development Project Term shall be
extended accordingly; and (b) the Development Project Term may, for purposes of
Section 2.l, be extended by approval of both the parties hereto in their
discretion.

     1.24  "Development Tasks" means those activities and responsibilities of
            -----------------
each party that will be part of the Development Project, as more fully described
from time to time in the Development Plan and Budget.  The Development Tasks
shall include with respect to a particular Licensed Product, as more fully
described in the Development Plan and Budget:

     (a)  preparation for [ * ];

     (b)  preclinical [ * ] performed in preparation for the [ * ] surveillance
          [ * ] all other applicable regulatory obligations [ * ] animal
          subjects;

     (c)  [ * ] of, and obtaining [ * ] including [ * ];

     (d)  [ * ] for activities under the [ * ];

     (e)  [ * ];

     (f)  preparation and [ * ];

     (g)  [ * ] as to specific indications, as required or agreed [ * ];

     (h)  [ * ] by one party hereunder to the other party [ * ] but not in any
          event less stringent than [ * ] and to the appropriate [ * ] with
          respect to [ * ] arising during the [ * ] for such [ * ] and
          associated with such [ * ] or any [ * ]; and

     (i)  such other activities, regardless of [ * ] that are [ * ] as
          determined by [ * ] in order to obtain [ * ].

Unless the parties agree otherwise, [ * ] shall have the primary responsibility
for the [ * ] described in [ * ] provided, however, that the parties hereto
shall [ * ] covered by any of the inventions or technologies [ * ] and shall
give [ * ] to such [ * ] provided it is able and willing [ * ] under terms and
conditions [ * ] to the parties hereto than the terms and conditions under which
[ * ] is able and willing to [ * ].

     1.25  "Discovered Antibody" means an antibody to a [ * ].
            -------------------

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -4-
<PAGE>

     1.26  "Distributor" means a person or entity, including any cooperative or
            -----------
group, involved in the acquisition of Licensed Products for distribution either
to other such persons or entities or to End Users, and who does not require, and
is not granted, any sublicense under any of the Project Technology or the
Background Technology (other than implied sublicenses to use and sell such
Licensed Products, by virtue of such Distributor's acquisition of the Licensed
Products from a person or entity authorized to sell them).

     1.27  "Effective Date" means August 30, 2001.
            --------------

     1.28  "Election Not to Co-Fund" means either (a) an election by ZGI made
            -----------------------
pursuant to Section 5.2 or Section 5.6 that ZGI will not, or will no longer,
fund and bear any of the North American Commercialization Costs with respect to
a particular Licensed Product or (b) an election by Serono made pursuant to
Section 5.6 following the end of the Product Term for a Licensed Product in
North America (determined under Section 1.60 without regard to Section 5.6) that
Serono will no longer fund and bear any of the North American Commercialization
Costs with respect to that Licensed Product.

     1.29  "Election Not to Co-Promote" means an election by ZGI made pursuant
            --------------------------
to Section 5.1 that ZGI will not participate in North American Co-Promotion
Tasks with respect to a particular Licensed Product.

     1.30  "End Use" means the retail sale, distribution or administration of a
            -------
Licensed Product by a pharmacy or other pharmaceutical dispensary or health
practitioner to a patient.  "End User" means such pharmacy, dispensary or
                             --------
practitioner.

     1.31  "Europe" means countries that are, at the relevant time, member
            ------
countries of the European Union, together with Switzerland and Norway; provided,
however, that for purposes of Section 7.2, an event that occurs in or with
respect to "Europe" shall mean any such event in or with respect to (a) [ * ],
or (b) [ * ].

     1.32  "Exclusivity Period" means, with respect to each Licensed Product:
            ------------------

     (a)   with respect to any country of the European Union (and any other
           country in the Territory in which applicable law would restrict the
           permissible duration of a period of exclusivity to the life of
           applicable patents), the period during the Product Term for such
           Licensed Product, until the Patent Expiration Date in such country
           with respect to the Patent Claims under Patent Rights in or to the
           ZGI IP or the Joint Project Technology applicable to such Licensed
           Product, or, if later, until all ZGI IP and Joint Project Technology
           applicable to such Licensed Product has been disclosed without
           restriction to the public (but, in this case, the Exclusivity Period
           will not last longer in such country than [ * ] years from the first
           Commercial Use of such Licensed Product in any country in the
           European Union unless and to the extent that European law or rules
           permit a longer such period of exclusivity); and

     (b)   with respect to any other country, the Product Term.

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -5-
<PAGE>

     1.33  "Exhibit" means an exhibit explicitly referenced as such in this
            -------
Agreement.  All such Exhibits are by such references incorporated into this
Agreement as if fully set forth herein.

     1.34  "Existing Third Party Agreement" means any Third Party Agreement
            ------------------------------
existing on the Effective Date and listed in Exhibit 1.34.

     1.35  "FDA" means the United States Food and Drug Administration or any
            ---
successor agency vested with administrative and regulatory authority to approve
testing and marketing of human pharmaceutical or biological therapeutic or
diagnostic products in the United States.

     1.36  "Ig Fusion Technology" means the Patent Rights for the items listed
            --------------------
in Exhibit 1.36.

     1.37  "IND" means an Investigational New Drug application, or its non-U.S.
            ---
equivalent, filed with a Regulatory Agency.

     1.38  "Information" means:  (a) all unpublished scientific and technical
            -----------
information received by a party from the other party pursuant to this Agreement,
or so received prior to the Effective Date but in contemplation of this
Agreement; and (b) all trade secrets or information relating to the business
affairs or finances of the disclosing party or its Affiliates, or of their
suppliers, agents, distributors, licensees or customers, designated confidential
and disclosed in tangible form by the disclosing party to the other party
pursuant to this Agreement.

     1.39  "Initiation" of Phase I, Phase II or Phase III Clinical Trials means
            ----------
the first administration of a Licensed Product to a patient in any such trial.

     1.40  "Known Ligand" means [ * ] or [ * ].
            ------------

     1.41  "Licensed Product" means any product intended for use in humans that
            ----------------
(a) [ * ] and (b) either (i) the manufacture, use, sale, offer to sell or import
of which, in the absence of a license granted under this Agreement or ownership
thereof, would directly or indirectly infringe one or more Patent Claims under
any Patent Rights in or to any [ * ]; or (ii) the research, development,
formulation, composition or manufacture of which was performed with the use of
or incorporates the [ * ]; or (iii) the development of which was in part funded
by ZGI under this Agreement.  Unless and to the extent a [ * ] is made the
subject of an agreement pursuant to [ * ] in connection with a product intended
for use in [ * ] that incorporates [ * ] is outside the scope of [ * ] and any
such product shall [ * ].

     1.42  "Licensed Product Trademarks" means any trademark adopted or used by
            ---------------------------
Serono to designate a Licensed Product anywhere in the Territory, together with
all rights therein to the extent applicable to particular jurisdictions.

     1.43  "Marketing Region" means each of North America, Europe and Japan.
            ----------------

     1.44  "Net Sales" of a Licensed Product means the sum of:
            ---------

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -6-
<PAGE>

     (a)  the gross amount invoiced by [ * ] for the sale of [ * ]:

          (i)    any direct or indirect [ * ] including [ * ] on account of
                 [ * ] or on account of [ * ];

          (ii)   any [ * ] including those imposed by [ * ];

          (iii)  applicable [ * ] to the extent specifically included in [ * ];

          (iv)   any [ * ] and any [ * ] to the extent specifically included in
                 the [ * ]

          (v)    amounts [ * ] with respect to [ * ];

          provided, however, that

                 (A)  the transfer of [ * ] between [ * ] and another entity
                      [ * ] other than for [ * ] shall not be considered a [ * ]
                      in such cases, [ * ] hereunder shall be determined using
                      the [ * ] allowed under this Section; and

                 (B)  if a [ * ] is used or disposed of by [ * ] in the
                      provision of a commercial service, or is [ * ] or
                      otherwise [ * ] in a transaction that is [ * ] to a person
                      or entity who is [ * ] then for purposes of this
                      definition[ * ] in such transaction shall be deemed to
                      [ * ] or [ * ] in such transaction [ * ] by the seller to
                      persons or entities who are [ * ] during the then-current
                      [ * ] less the [ * ]

     (b)  the [ * ] into which such [ * ] is incorporated.

     1.45  "North America" means Canada and the United States of America.
            -------------

     1.46  "North American Commercialization Costs" means those costs incurred
            --------------------------------------
or otherwise borne or to be borne by [ * ] in connection with the [ * ] or in
accordance with the applicable [ * ] with respect to the [ * ] of a [ * ] as
more fully described in Exhibit 1.46.  The North American Commercialization
Costs shall be accounted for by each party in accordance with the cost
accounting principles described in Exhibit 1.46.

     1.47  "North American Co-Promotion Tasks" means those tasks with respect to
            ---------------------------------
the co-promotion of a Licensed Product in North America, as more fully described
from time to time in an applicable Commercialization Plan and Budget.  Unless
and until ZGI makes an Election Not to Co-Promote or an Election Not to Co-Fund,
the North American Co-Promotion Tasks will include, as more fully described in
the applicable Commercialization Plan and Budget:

     (a)  the preparation of [ * ] the dissemination of [ * ] and/or the
          engagement of [ * ] all of which [ * ] shall, to the extent not [ * ]
          and subject to [ * ] feature the [ * ] and the [ * ] which [ * ] shall
          be given [ * ] with [ * ] in such [ * ];

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -7-
<PAGE>

     (b)   the deployment [ * ] in North America from [ * ] to be assigned and
           coordinated by [ * ] in a manner considered [ * ]; and

     (c)   designing and conducting one or more [ * ] for the parties' [ * ],
           and, subject to the terms and conditions set forth in [ * ] arrange
           for the [ * ] and [ * ] regarding the [ * ].

     1.48  "Patent Claim" means a claim of any unexpired granted Patent Rights
            ------------
that have not:  (a) lapsed, been disclaimed, withdrawn, canceled, or abandoned
or admitted to be invalid or unenforceable; (b) been finally rejected or held
invalid by a decision of a patent-granting authority beyond right of review or
appeal; or (c) been held invalid or unenforceable in an unappealable decision of
a court or competent body having jurisdiction (including a decision which was
appealable, but which was not timely appealed).

     1.49  "Patent Contacts" means the patent practitioners appointed by each
            ---------------
party to serve as contact persons between the parties from time to time in
relation to patent matters under this Agreement.  The parties' initial Patent
Contacts shall be designated, respectively, by each party within thirty (30)
days following the Effective Date.  Each party shall promptly notify the other
party of any substitution of other personnel as its Patent Contact(s).

     1.50  "Patent Country" means, with respect to particular Patent Rights, the
            --------------
country in which such Patent Rights are pending or granted.

     1.51  "Patent Defense and Enforcement Costs" means all internal and
            ------------------------------------
external costs associated with the enforcement of Patent Rights against actual
or suspected infringers, defense of Patent Rights against attacks on their
validity, or defense of a Licensed Product against Third Party claims of patent
infringement.

     1.52  "Patent Expiration Date" means, on a Patent Country-by-Patent Country
            ----------------------
basis, the first date on which no Patent Claims exist within such Patent
Country.

     1.53  "Patent Prosecution Costs" means all internal and external costs
            ------------------------
associated with the preparation (of applications and otherwise), filing,
prosecution, maintenance, conduct of opposition or interference proceedings
under or with respect to Patent Rights.

     1.54  "Patent Rights" means:  (a) patent applications; (b) all provisional,
            -------------
divisional, continuation (in whole or in part) or substitute applications with
respect to any of the applications described in (a); (c) all non-U.S.
applications based on the applications described in (a) or (b); (d) all issued
or granted patents resulting from any of the applications described above; and
(e) all issued or granted reissue, re-examination, renewal or extension patents,
supplementary protection certificates, and confirmation or registration patents
or patents of addition based on any of the patents described in (d).

     1.55  "Phase I Clinical Trials" means human clinical trials intended to
            -----------------------
obtain initial data regarding the safety of a Licensed Product, whether
constituting Phase I trials in the United States or similar trials in any other
part of the Territory.

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -8-
<PAGE>

     1.56  "Phase II Clinical Trials" means human clinical trials intended to
            ------------------------
study the safety, dose range and efficacy of a Licensed Product that do not
constitute Phase III Clinical Trials of such Licensed Product, whether
constituting Phase II trials in the United States or similar trials in any other
part of the Territory.

     1.57  "Phase III Clinical Trials" means human clinical trials intended to
            -------------------------
determine the statistical efficacy and safety of a Licensed Product and which
are intended to be the final stage of clinical testing prior to and in support
of the filing of a PLA, whether constituting Phase III trials in the United
States or similar trials in any other part of the Territory.

     1.58  "PLA" means a Product License Application, a Biologics License
            ---
Application or a non-U.S. equivalent of either filed with a Regulatory Agency.

     1.59  "Product Team" means the committee described in Section 3.2, two (2)
            ------------
members of which shall be the Project Contacts.  The Product Team may have any
number of other members as may be nominated from time to time by either or both
of ZGI and Serono and approved as Product Team members by Steering Committee
Action.  While the parties need not be equally represented in number of members
on the Product Team, the Product Team will be co-led by the two (2) Project
Contacts.

     1.60  "Product Term" except as is otherwise provided in Section 5.6, means
            ------------
with respect to each Licensed Product in each country in the Territory or the
ZGI Territory, if any, the period from the Effective Date until the later of:

     (a)   the last Patent Expiration Date in such country with respect to the
           Patent Claims under Patent Rights in or to the [ * ], as applicable
           to such Licensed Product; and

     (b)   the expiration of [ * ] years following the first Commercial Use of
           such Licensed Product in such country;

provided, however, that if as of the [ * ] anniversary of the Effective Date,
such Patent Expiration Date has occurred in such country, and there has been no
Commercial Use of such Licensed Product in such country, then the Product Term
as to such Licensed Product shall end on such [ * ] anniversary of the Effective
Date.

     1.61  "Project Contacts" means the persons appointed by each party to serve
            ----------------
as contact persons between the parties from time to time in relation to the
coordination of research and development efforts under this Agreement.  The
parties' initial Project Contacts shall be designated, respectively, by each
party within thirty (30) days following the Effective Date.  Each party shall
promptly notify the other party of any substitution of other personnel as its
Project Contact.

     1.62  "Project Technology" means all inventions, discoveries, know-how,
            ------------------
methods, processes, data, information, technology, research tools, compositions,
tangible materials (including nucleic acids, peptides, vectors, proteins,
assays, and the like) and formulas that are invented, discovered, developed or
otherwise generated by either party, their respective Affiliates

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -9-
<PAGE>

or both parties jointly during and in the course of a Development Project
conducted pursuant to this Agreement and co-funded pursuant to Article Four, and
all Patent Rights, trade secrets, and other intellectual property rights therein
and thereto anywhere in the world. Project Technology invented, discovered,
developed or otherwise generated by Serono and its Affiliates is the "Serono
                                                                      ------
Project Technology." Project Technology invented, discovered, developed or
------------------
otherwise generated by ZGI and its Affiliates is the "ZGI Project Technology."
                                                      ----------------------
Project Technology that is jointly invented, discovered, developed or otherwise
generated by Serono and ZGI or their respective Affiliates is the "Joint Project
                                                                   -------------
Technology." The parties shall follow the principles of inventorship under U.S.
----------
patent law in order to determine the party that invented, discovered, developed
or otherwise generated any item of Project Technology.

     1.63  "Reasonable Commercial Efforts" means the exertion on a substantially
            -----------------------------
continuous basis of efforts as would normally be devoted to the applicable task
by commercial parties with similar resources to those of the applicable party,
where such parties are highly motivated to accomplish such task to the maximum
extent practicable, taking into account, without limitation, consideration of
the anticipated safety and efficacy of a subject product, its likely
competition, the strength of its proprietary position, regulatory factors, and
other scientific, medical and commercial factors.  Reasonable Commercial Efforts
will not mean that a party commits that it will actually accomplish the
applicable task, or that it will devote thereto efforts or resources beyond
those that a prudent commercial enterprise would devote, even though remaining
motivated to do so as described above.

     1.64  "Regulatory Agency" means (a) the FDA or (b) any regulatory body with
            -----------------
similar regulatory authority in any other jurisdiction anywhere in the world.

     1.65  "Regulatory Approval" means the authorization by an appropriate
            -------------------
Regulatory Agency to market and sell a Licensed Product in a jurisdiction,
including, to the extent required, any governmental pricing approval for such
Licensed Product in such jurisdiction; provided, however, that with respect to
jurisdictions in which the government is the primary provider of insurance, or
otherwise pays, for prescription drugs to consumers, the authorization for
Regulatory Approval shall include approval of government price reimbursement
levels, unless the Licensed Product is distributed without such reimbursement
authorization.

     1.66  "Research Materials" means any tangible materials that are delivered
            ------------------
by one party to the other (or to the other's Contractors) either (a) as part of
the delivering party's Background Technology for use in the Development Project
or that are developed in the course of the Development Project and are provided
by either party to the other as part of the Project Technology or (b) for use in
connection with any Development Task, even though such materials are not
themselves part of the Background Technology or Project Technology, such as [ *
], and other reagents and materials to be used in comparative studies such as
toxicology studies.

     1.67  "Rest of World" means all countries of the world except those within
            -------------
North America.

     1.68  "S.A." means Serono S.A., a Swiss corporation having offices at Case
            ----
Postale 11, CH-1267 Vich-Coinsins, Switzerland.

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.


                                      -10-
<PAGE>

     1.69  "Senior Executives" means one or more executive officers of a party
            -----------------
or its Affiliates (other than members of the Steering Committee), who have
direct reporting responsibility to the CEO of that party, and who are appointed
from time to time by the CEO of that party, to conduct one or more of the
dispute resolution processes described in Section 18.1 hereof.

     1.70  "Serono Background Technology" means (a) any inventions, discoveries,
            ----------------------------
know-how, methods, processes, data, information, technology, research tools,
compositions, formulas and tangible materials Controlled by Serono or its
Affiliates that (i) as of the Effective Date, Serono knows or should know (based
on at least preliminary data) to be necessary, (ii) other than Project
Technology, are actually used by Serono or its Affiliates, during and in the
course of the Development Project, or (iii) are included in Serono Background
Technology by consent of the Controlling party pursuant to Section 4.2, in any
case for the development, manufacture or use of Licensed Products, including the
technology listed in Exhibit 1.70 hereto (the "Serono Technology"); (b) other
                                               -----------------
than Project Technology, any and all improvements to the Serono Technology, to
the extent invented, discovered, developed or otherwise generated by Serono or
its Affiliates during any Development Project Term and prior to the time, if
any, at which Serono has elected to terminate its roles and responsibilities
with respect to all Development Projects pursuant to Section 4.8; and (c) all
Patent Rights, trade secrets, and other intellectual property rights anywhere in
the world in and to any of the Serono Technology and improvements described in
(a) or (b) of this Section.

     1.71  "Serono IP" means the Serono Project Technology, the Serono
            ---------
Background Technology, and the Serono Production Technology.

     1.72  "Serono Production Technology" means the most current form of any and
            ----------------------------
all technology, know-how, biological materials, and reagents Controlled by
Serono that are actually applied by Serono or its Affiliates to the scale up or
manufacture of a Licensed Product under or in connection with this Agreement, to
the extent such technology is useful for the, manufacture of the Licensed
Product, and all Patent Rights, trade secrets, and other intellectual property
rights anywhere in the world therein and thereto.

     1.73  "Steering Committee" means a committee of six (6) members, three (3)
            ------------------
of whom will be designated in writing by each of ZGI and Serono.  The parties'
respective representatives on the initial Steering Committee shall be designated
by the parties within thirty (30) days following the Effective Date.  If at any
time a vacancy occurs (whether due to death, disability, resignation, removal by
a party of its designee by written notice to the other party, or otherwise), the
vacancy will be filled as soon as is reasonably practicable by designation by
the party that originally designated the prior incumbent.  In the meantime, the
Steering Committee shall continue to function with its remaining members,
provided that any Steering Committee Action described in subsection 1.74(a) will
continue to require the consent of at least four (4) members.

     1.74  "Steering Committee Action" means an official act, decision, or
            -------------------------
ruling of the Steering Committee, which shall require in each case that at least
one (1) of the following applies:


[ * ]  designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -11-
<PAGE>

     (a)  a minimum of [ * ] of the Steering Committee have consented thereto,
          where such consent is given either in writing (including by email or
          facsimile) or by vote at a meeting of the Steering Committee and
          subsequently entered into the minutes of such meeting;

     (b)  at least [ * ] of the Steering Committee have consented thereto (in
          the manner described above), and have further put the matter before
          [ * ] as described in [ * ] and the act, decision, or ruling has
          received the [ * ];

     (c)  the parties' [ * ] have put the matter before the parties' [ * ] as
          described in [ * ] and the act, decision, or ruling has either (i)
          received the [ * ] of the [ * ] of [ * ] or (ii) with respect to (A)
          matters that relate solely to [ * ] of a [ * ], or (B) matters that
          relate solely to the [ * ] following an [ * ], has received the
          written approval [ * ]

     (d)  [ * ] pursuant to [ * ] results in the adoption of the act, decision,
          or ruling as constituting [ * ].

A Steering Committee Action may include the rescinding or amendment of any prior
Steering Committee Action.

     1.75  "St. Jude License Agreement" means that certain License Agreement
            --------------------------
with St. Jude Children's Research Hospital, as listed in Exhibit 1.34 as a Third
Party Agreement, as amended.

     1.76  "Sublicensee" means a Third Party to whom Serono or ZGI has extended
            -----------
a sublicense consistent with Article Ten.

     1.77  "TACI" means the receptor described in International Patent
            ----
Application [ * ].

     1.78  "Term" shall have the meaning set forth in Section 17.1.
            ----

     1.79  "Territory" means the world, unless and until any country or
            ---------
countries are removed from the Territory and made part of the ZGI Territory as
provided herein, in which case "Territory" means the remainder of the world
other than such country or countries.

     1.80  "Third Party" means any person or entity other than ZGI, Serono, or
            -----------
their respective Affiliates.

     1.81  "Third Party Agreement" means any agreement entered into with a Third
            ---------------------
Party by either ZGI, Serono, or their respective Affiliates, or any amendment
thereto, whereby royalties, fees or other payments are to be made to the Third
Party based on  (a) exploitation of intellectual property rights of the Third
Party or (b) the provision of products, materials or services sourced from the
Third Party, where (a) and/or (b) are used in the course of the research,
development or manufacturing, marketing, distribution or sales of a Licensed
Product, or whereby any other


[ * ]  designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -12-
<PAGE>

restrictions, limitations or conditions are imposed on making, using, selling,
offering for sale, importing, or otherwise exploiting any Licensed Product.

     1.82  "Third Party Commercial Use Fees" means [ * ] paid or payable by
            -------------------------------
[ * ] or their respective [ * ] with respect to [ * ] pursuant to a [ * ].

     1.83  "Third Party Development Fees" means [ * ] paid or payable by [ * ]
            ----------------------------
or their respective [ * ] in connection with a [ * ] pursuant to a [ * ].

     1.84  "United States of America" or "United States" means the United States
            ------------------------      -------------
of America and its territories and possessions, including the Commonwealth of
Puerto Rico.

     1.85  "ZGI Background Technology" means (a) any inventions, discoveries,
            -------------------------
know-how, methods, processes, data, information, technology, research tools,
compositions, formulas and tangible materials Controlled by ZGI or its
Affiliates that (i) as of the Effective Date, ZGI knows or should know (based on
at least preliminary data) to be necessary, (ii) other than Project Technology,
are actually used by ZGI or its Affiliates, during and in the course of the
Development Project, or (iii) are included in ZGI Background Technology by
consent of the Controlling party pursuant to Section 4.2, in any case for the
development, manufacture or use of Licensed Products, including the technology
listed in Exhibit 1.85 hereto (the "ZGI Technology"); (b) other than Project
                                    --------------
Technology, any and all improvements to the ZGI Technology, to the extent
invented, discovered, developed or otherwise generated by ZGI or its Affiliates
during any Development Project Term and prior to the time, if any, at which ZGI
has elected to terminate its roles and responsibilities with respect to all
Development Projects pursuant to Section 4.8; and (c) all Patent Rights, trade
secrets, and other intellectual property rights anywhere in the world in and to
any of the ZGI Technology and improvements described in (a) or (b) of this
Section.  Notwithstanding the foregoing, the Ig Fusion Technology shall not be
deemed to fall within the term "ZGI Background Technology".

     1.86  "ZGI IP" means the ZGI Project Technology and the ZGI Background
            ------
Technology.

     1.87  "ZGI Territory" means such country or countries, if any, that is or
            -------------
are removed from the Territory and made part of the ZGI Territory as provided
herein.

     1.88  Certain Terminology.  Where words and phrases are used herein in the
           -------------------
singular, such usage is intended to include the plural forms where appropriate
to the context, and vice versa.  The words "including", "includes" and "such as"
                                            ---------    --------
are used in their non-limiting sense and have the same meaning as "including
without limitation" and "including but not limited to".  References to Articles,
Sections, subsections, and clauses are to the same with all their subparts as
they appear in this Agreement.  "Herein" means anywhere in this Agreement.
                                 ------
"Hereunder" and "hereto" means under or pursuant to any provision of this
----------       ------
Agreement.


[ * ]  designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -13-
<PAGE>

                                  ARTICLE TWO
                   Scope and Exclusivity of the Collaboration

     2.1  Exclusivity.    Except as otherwise provided herein, ZGI and Serono
          -----------
agree to work exclusively with each other (and each other's Contractors, if any)
during the Development Project Term with respect to the discovery and
development of products [ * ] that incorporate either a [ * ] or a [ * ] or
both, whether alone or as part of a [ * ].

     2.2  First Negotiation and First Refusal Rights.
          ------------------------------------------

     (a) Unless and until an [ * ] is made the subject of an agreement pursuant
to this Section, the parties acknowledge and agree that [ * ] are not within the
scope of their collaboration or the Development Project.

     (b) ZGI hereby agrees, with respect to any known or suspected [ * ] any
known or suspected [ * ] and any known or suspected [ * ] known to or suspected
by it as of the Effective Date, or discovered by it during the Development
Project Term (or that is so known to, suspected by, or so discovered by its
Affiliates, to the extent ZGI Controls rights to such [ * ]), that it shall, on
or before the [ * ] after the Effective Date, the [ * ] after the identification
of a known or suspected [ * ], or the [ * ] after the expiration of any and all
prior rights of Novo Nordisk A/S or its Affiliates with respect to such [ * ],
whichever occurs last, notify Serono of such [ * ], and concurrently provide to
Serono ZGI's reasons for categorizing it as an [ * ] and all data and
information then available to ZGI with respect to such [ * ].

     (c) ZGI hereby agrees, with respect to any known or suspected [ * ], any
known or suspected [ * ] and any known or suspected [ * ] of which it is
required to give notice to Serono under subsection (b) above:

     (i)   ZGI will, during the [ * ] following its notice under subsection (b),
           if requested by Serono, make appropriate representatives available to
           meet with Serono's representatives to provide a fuller description of
           the data and information then available to ZGI with respect to such
           [ * ], and to answer Serono's questions in that regard;

     (ii)  ZGI shall engage in good faith negotiations with Serono over a period
           of at least [ * ] following the end of the [ * ] period described in
           clause (i) above, in an attempt to reach agreement with Serono
           (either in a definitive agreement or a mutually signed term sheet
           which both parties thereafter diligently work to memorialize in a
           definitive agreement) with respect to the development and
           commercialization by Serono of one or more products based on or
           incorporating that [ * ];

     (iii) if no agreement is reached pursuant to clause (ii) above, ZGI hereby
           agrees that it shall promptly notify Serono if at any time during the
           Term ZGI or any of its Affiliates desires to grant to any Third Party
           any right or license in or to such [ * ] anywhere in the Territory,
           or desires to develop or commercialize one or more


[ * ]  designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -14-
<PAGE>

           products based on or incorporating such [ * ] anywhere in the
           Territory, and in that event ZGI shall again engage in good faith
           negotiations with Serono over a period of at least [ * ] following
           such notice under this clause, to reach agreement with Serono (either
           in a definitive agreement or a mutually signed term sheet which both
           parties thereafter diligently work to memorialize in a definitive
           agreement) with respect to the development and commercialization by
           Serono of one or more products based on or incorporating that [ * ];
           and

     (iv)  if no agreement is reached pursuant to clause (iii) above, ZGI shall
           give Serono at least [ * ] written notice prior to signing any
           agreement with any Third Party (either as a definitive agreement or a
           mutually signed term sheet) with respect to such [ * ] in which
           agreement ZGI is willing to extend to such Third Party terms that
           are, in any material respect, more favorable for the Third Party than
           the terms ZGI was willing to extend to Serono in the course of the
           negotiations pursuant to clause (iii) above, and it shall afford
           Serono the opportunity during such notice period to accept and agree
           to such agreement on such more favorable terms in lieu of such Third
           Party; provided, however, that if ZGI has not entered into an
           agreement (either in a definitive agreement or a mutually signed term
           sheet) with a Third Party pursuant to this clause [ * ], then clause
           (iii) above (and potentially this clause (iv)) shall again be
           applicable to any right or license in or to such [ * ] which ZGI or
           any of its Affiliates may thereafter desire to grant to any Third
           Party anywhere in the Territory.

     (d)   Serono hereby agrees, with respect to any known or suspected [ * ],
any known or suspected [ * ] or any known or suspected [ * ] known to, or
suspected by, it as of the Effective Date, or discovered by it during the
Development Project Term (or that is so known to, suspected by, or so discovered
by its Affiliates, to the extent Serono Controls rights to such [ * ]) that it
shall promptly notify ZGI if at any time during the Development Project Term
hereunder Serono or any of its Affiliates desires to grant to any Third Party
any right or license in or to such [ * ] in North America. Such notification
will include all data and information then available to Serono with respect to
such [ * ] and Serono's reasons for categorizing it as [ * ].

     (e)   Serono hereby agrees, with respect to any known or suspected [ * ],
any known or suspected [ * ] or any known or suspected [ * ] of which it is
required to give notice to ZGI under subsection (d) above:

     (i)   Serono will, during [ * ] following its notice under subsection (d),
           if requested by ZGI, make appropriate representatives available to
           meet with ZGI's representatives to provide a fuller description of
           the data and information then available to Serono with respect to
           such [ * ], and to answer ZGI's questions in that regard;

     (ii)  Serono shall engage in good faith negotiations with ZGI over a period
           of at least [ * ] described in clause (i) above, in an attempt to
           reach agreement with ZGI (either in a definitive agreement or a
           mutually signed term sheet which both parties thereafter diligently
           work to memorialize in a definitive agreement) with


[ * ]  designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -15-
<PAGE>

           respect to the development and commercialization by ZGI of one or
           more products based on or incorporating that [ * ] for the North
           American market; and

     (iii) if no agreement is reached pursuant to clause (ii) above, Serono
           shall give ZGI at least [ * ] written notice prior to signing any
           agreement with any Third Party (either as a definitive agreement or a
           mutually signed term sheet) with respect to such [ * ] for the North
           American market in which agreement, Serono is willing to extend to
           such Third Party terms that are, in any material respect, more
           favorable for the Third Party than the terms Serono was willing to
           extend to ZGI in the course of the negotiations pursuant to clause
           (ii) above, and it shall afford ZGI the opportunity during such
           notice period to accept and agree to such agreement on such more
           favorable terms in lieu of such Third Party; provided, however, that
           if Serono has not entered into an agreement (either in a definitive
           agreement or a detailed and mutually signed term sheet) with a Third
           Party pursuant to this clause (iii) [ * ] then clause (ii) above (and
           potentially this clause (iii)) shall again be applicable to any right
           or license in or to such [ * ] which Serono or any of its Affiliates
           may thereafter desire to grant to any Third Party for North America.

                                 ARTICLE THREE
                       Coordination of the Collaboration

     3.1  Steering Committee Role and Responsibilities.
          --------------------------------------------

     (a)  The Steering Committee shall be responsible for the overall direction
of the parties' collaboration hereunder, including oversight of the Product
Team, if any, the Patent Contacts and the Commercialization Team, if any.  The
responsibilities of the Steering Committee shall include adoption and amendment
of the Development Plan and Budget, adoption and amendment of Commercialization
Plans and Budgets, if any, and resolution of disputes occurring at the Product
Team or Commercialization Team levels or between the parties' respective Patent
Contacts.  The Steering Committee may on its own initiative and at any time act,
or reverse action, within the scope of the Product Team's, Patent Contacts', or
Commercialization Team's responsibilities.  The Steering Committee shall be
guided by the general principle that Development Tasks and North American Co-
Promotion Tasks will be allotted to the respective parties, directly or working
through one or more Contractors, as shall appear most likely to expedite the
timely development and marketing, distribution and sales of Licensed Products
hereunder, taking into account as appropriate the parties' respective
capabilities, facilities, and personnel, and the timely availability thereof for
such purposes.  The Steering Committee shall have no oversight with respect to
the commercialization of any Licensed Product for which either party has made an
Election Not to Co-Fund and all matters relating to the commercialization of
such Licensed Product shall be determined by the party that continues to fund
such commercialization.

     (b)  The Steering Committee shall meet face-to-face at least semi-annually
at mutually agreed upon times and locations.  Unless otherwise agreed, the
location of such meetings will alternate between the parties' headquarters.
Either or both of the parties may bring other personnel employed by them or
their Contractors to meetings of the Steering Committee as


[ * ]  designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -16-
<PAGE>

observers or to present data and information relative to the Development
Projects; provided that the attendance of employees of a Contractor shall be
subject to the consent of the other party, which consent shall not be
unreasonably withheld. The Steering Committee shall also address issues as they
arise in the interim via telephone conference, videoconference or electronic
mail. A written agenda for each face-to-face meeting shall be circulated in
advance of the meeting, and written minutes of each meeting shall be taken and
shall include the issues discussed and action items, if any, arising from the
meeting. Meeting minutes and written summaries of any action taken by way of
interim communications shall be promptly submitted (i) to the Project Contacts,
(ii) to all members of the Steering Committee, (iii) to the extent such minutes
or action involve Patent Rights, to the Patent Contacts, and (iv) to the extent
such minutes or action involve matters related to commercialization of a
Licensed Product, to the Commercialization Contacts. Each face-to-face meeting
of the Steering Committee shall include a review and approval (or amendment) by
Steering Committee Action of minutes from the prior meeting and of all actions
taken through interim communications.

     (c)  Among its other responsibilities[ * ] shall review and may, by [ * ]
approve one or more [ * ] that are proposed to be entered by [ * ] following the
[ * ].

     (d)  All formal actions of the Steering Committee must be taken by Steering
Committee Action as defined herein.

     3.2  Product Team and Project Contacts Roles and Responsibilities.
          ------------------------------------------------------------

     (a)  The Product Team, consisting of at least the two (2) Project Contacts,
shall be responsible for managing day-to-day research and development activities
relating to Licensed Products, in accordance with the Development Plan and
Budget.  The Product Team shall be responsible for the preparation and
submission to the Steering Committee, within [ * ] after the Effective Date, of
an initial Development Plan and Budget covering at least [ * ] following the
Effective Date.  The Product Team shall be disbanded following [ * ] of the
Effective Date unless the Steering Committee determines that it should continue
to function beyond that time.

     (b)  The Product Team shall meet as often as is deemed necessary by the
Project Contacts.  Such meetings shall take place in person, by videoconference
or by telephone conference as mutually agreed by the Project Contacts.  There
shall be an agenda for each meeting of the Product Team and minutes of each
meeting shall be taken and shall include the issues discussed and action items,
if any, arising from such meeting.  Meeting minutes shall be submitted to the
members of the Product Team and the Steering Committee.

     (c)  All formal actions of the Product Team must receive the approval of
the two (2) Project Contacts, either in writing (including by email or
facsimile) or by vote at a meeting of the Product Team, and all formal actions
shall subsequently be entered into the minutes of meetings of the Product Team.
In the absence of such mutual approval, either Project Contact may by formal
written notice to the Steering Committee declare the existence of a dispute at
the Project Team level, and thereby request that such dispute be resolved by the
Steering Committee.


[ * ]  designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -17-
<PAGE>

     (d)  In addition to the formal activities of the Product Team, each party's
Project Contact will also be available throughout the Development Project Term
(including, following any disbanding of the Product Team) to answer any
reasonable questions from the other party's Project Contact.

     3.3  Commercialization Team and Commercialization Contacts Roles and
          ---------------------------------------------------------------
Responsibilities.
----------------

     (a)  A Commercialization Team shall be formed by the Commercialization
Contacts, with approval by Steering Committee Action, with respect to any
Licensed Product developed in whole or part in the Development Project.  Each
such Commercialization Team shall be formed within [ * ] following the
appointment of the Commercialization Contacts or prior to the [ * ] following
the Initiation of Phase III Clinical Trials of such Licensed Product, whichever
is later.

     (b)  The Commercialization Team shall be responsible for (i) the
preparation and submission to the Steering Committee of an initial
Commercialization Plan and Budget with respect to a Licensed Product, covering a
period of at least [ * ] years following the first Regulatory Approval of such
Licensed Product, and, as appropriate from time to time and not less often than
annually, for the preparation of proposed updates and amendments to the
Commercialization Plan and Budget, to cover a rolling, multi-year period of at
least [ * ] years, for submission to the Steering Committee and (ii) planning
and coordinating the North American Co-Promotion Tasks of the parties.

     (c)  If (i) ZGI makes an Election Not to Co-Promote or (ii) either party
makes an Election Not to Co-Fund, with respect to a Licensed Product, the
Commercialization Team with respect to that Licensed Product, if any such
Commercialization Team shall theretofore have been formed, shall be disbanded.
If either party makes an Election Not to Co-Fund with respect to a Licensed
Product, no further Commercialization Plans and Budgets need be prepared with
respect to that Licensed Product.  For so long as ZGI is co-funding the North
American Commercialization Costs for a Licensed Product and without regard to
the fact that the Commercialization Team with respect to such Licensed Product
has been disbanded because ZGI has made an Election Not to Co-Promote, Serono
shall continue to prepare and provide to ZGI a Commercialization Plan and Budget
and shall make appropriate employees reasonably available to ZGI to review and
answer questions regarding such Commercialization Plan and Budget; provided that
such Commercialization Plan and Budget shall not be subject to approval by
Steering Committee Action.

     (d)  The Commercialization Team shall monitor the parties' conduct of the
North American Co-Promotion Tasks, in relation to the planned timelines and
budgets, including details regarding external costs and internal costs incurred
against the budgeted costs.  The Commercialization Team shall report any actual
or anticipated cost overruns in excess of [ * ] in any budgeted category to the
Steering Committee.  Likewise, the Commercialization Team shall monitor progress
of the marketing, distribution and sales of Licensed Products versus plans and
report any actual or anticipated timeline delays to the Steering Committee.

[ * ]  designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -18-
<PAGE>

     (e)  The Commercialization Team shall meet as often as is deemed necessary
by the Commercialization Contacts.  Such meetings shall take place in person, by
videoconference or by telephone conference as mutually agreed by the
Commercialization Contacts.  There shall be an agenda for each meeting of the
Commercialization Team and minutes of each meeting shall be taken and shall
include the issues discussed and action items, if any, arising from such
meeting.  Meeting minutes shall be submitted to the members of the
Commercialization Team and the Steering Committee.

     (f)  All formal actions of the Commercialization Team must receive the
approval of the two (2) Commercialization Contacts, either in writing (including
by email or facsimile) or by vote at a meeting of the Commercialization Team,
and all formal actions shall subsequently be entered into the minutes of
meetings of the Commercialization Team.  In the absence of such mutual approval,
either Commercialization Contact may by formal written notice to the Steering
Committee declare the existence of a dispute at the Commercialization Team
level, and thereby request that such dispute be resolved by the Steering
Committee.

     (g)  In addition to the formal activities of the Commercialization Team,
except to the extent that a party duly makes an Election Not to Co-Fund with
respect to a Licensed Product or ZGI duly makes an Election Not to Co-Promote,
each party's Commercialization Contact will also be available to answer any
reasonable questions from the other party's Commercialization Contact.

                                  ARTICLE FOUR
                 Discovery and Development of Licensed Products

     4.1  Research and Development Efforts. Each of the parties shall use its
          --------------------------------
respective Reasonable Commercial Efforts throughout the Development Project Term

     (a)  to perform the respective [ * ] allotted to it in the [ * ] and to do
          so in accordance with the [ * ]; and

     (b)  to assist and to cooperate as requested with the other party's [ * ]
          to do the same as to its own [ * ] under the [ * ].

Each party agrees that Development Tasks shall be established and assigned to
expedite the timely and efficient development of Licensed Products hereunder.
In the event ZGI has terminated its roles and responsibilities under a
Development Project for a Licensed Product pursuant to Section 4.8, Serono shall
use Reasonable Commercial Efforts to expedite the timely development of the
Licensed Product.

     4.2  Invention Disclosures; Provision of Information. ZGI shall provide
          -----------------------------------------------
Serono full and prompt disclosure of the ZGI Background Technology and Ig Fusion
Technology as required for the development of Licensed Products hereunder.  Each
party will provide to the other party full and prompt disclosure of any new
Project Technology and any new improvements described in subsection 1.84(b),
including any invention disclosures submitted to its patent department which
disclose such Project Technology or improvements.  Each party shall from time to
time in


[ * ]  designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -19-
<PAGE>

the course of performing Development Tasks bring to the attention of the Product
Team any inventions, discoveries, know-how, methods, processes, data,
information, technology, research tools, compositions, formulas and tangible
materials Controlled by a party or its Affiliates that it reasonably believes
may be useful for development, manufacture or use of a Licensed Product and any
such items may be included in Serono Background Technology or ZGI Background
Technology, as appropriate, under reasonable conditions and upon written consent
of the Controlling party of each such item. Nothing herein or otherwise shall
require any party to disclose information with respect to which such party has
an obligation of confidentiality to a Third Party, but each party will exert its
Reasonable Commercial Efforts to bring to the attention of the Steering
Committee any such Third Party restrictions as may be relevant hereunder.

     4.3  Regulatory Matters.
          ------------------

     (a)  Serono shall have the sole right to obtain Regulatory Approvals and
approvals to manufacture Licensed Product in the Territory which shall be held
by and in the name of Serono or its designees, and Serono shall own all
submissions made in connection therewith.  All formulary, price, reimbursement
or other marketing approvals in the Territory shall also be obtained by and in
the name of Serono or its designees.

     (b)  Serono shall be the sole contact for and will otherwise take the lead
in all interactions with Regulatory Agencies concerning the Licensed Product.
ZGI at the request of Serono will supply representatives to meet with Regulatory
Agencies, if necessary in view of the Development Tasks assigned to ZGI to
obtain or maintain Regulatory Approvals.

     4.4  Selection and Supervision of Personnel. Each party shall be
          --------------------------------------
responsible for the selection and supervision of its personnel who are assigned
any Development Tasks pursuant to this Agreement.

     4.5  Development Costs Attributable to Japan. Serono shall fund and shall
          ---------------------------------------
bear one hundred percent (100%) of the costs of any and all tasks that are
attributable exclusively to the development, testing or registration of a
Licensed Product for Japan or the Japanese market or to seeking Regulatory
Approval in Japan, whether or not such tasks are performed wholly or partly
outside of Japan and whether or not they are performed by ZGI or Serono.

     4.6  Other Development Costs; Quarterly Accountings. [ * ] of all
          ----------------------------------------------
Development Costs incurred following the Effective Date and pursuant to the
Development Plan and Budget, other than those to be borne by Serono under
Section 4.5, shall be funded and borne by Serono, and [ * ] of such Development
Costs shall be funded and borne by ZGI, regardless of which party is allocated
or performs one or more of the relevant Development Tasks.  Each party shall
submit to the Product Team at least quarterly (or on such other schedule as may
be determined by Steering Committee Action) a written and itemized accounting of
the expenditures, costs, and other resources actually devoted by it to the
Development Tasks in accordance with the Development Plan and Budget since the
last such accounting.  Such accountings shall be considered to be Information
subject to protection under Article Thirteen.  The parties' quarterly
accountings will be reviewed and approved in whole or in part (and/or returned
in whole or in part to a party for correction or adjustment prior to
resubmission) by action of the Product Team.  The Product


[ * ]  designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -20-
<PAGE>

Team will notify each party on a quarterly basis of the results of such review
by it of the accountings of both parties. To the extent that both parties'
accountings for prior expenditures, costs and other resources for the
Development Plan and Budget have been so approved, the Product Team will direct
by a quarterly invoice (with copies to both parties) that the party which has
borne less than its share of the aggregate Development Costs (net of those to be
borne by Serono under Section 4.5), taking into account all prior reconciliation
invoices under this section, shall reconcile such disparity by paying to the
other party an amount sufficient to bring the respective amounts borne by each
party, as of the end of the period covered by such accountings, back to the
ratio of [ * ]. Any such invoice shall be payable by Serono or ZGI, as the case
may be, to the other party hereto in accordance with Article Nine and within
[ * ] after receipt of invoice.

     4.7  Third Party Development Fees. No amounts paid to [ * ] shall be
          ----------------------------
allowable as part of the [ * ] borne by a party hereto except to the extent that
the same are either paid to a [ * ], paid to [ * ] in the normal course of
clinical development (including payments to [ * ] or, except for amounts payable
by [ * ] pursuant to [ * ] paid pursuant to a [ * ] that is entered after the
[ * ] and with the approval of [ * ] in accordance with [ * ] . All other [ * ]
if any (including any such amounts payable by [ * ] under the [ * ] or an [ * ]
pursuant to [ * ] shall be borne solely by [ * ] that is party to the [ * ].

     4.8  Early Termination of Development Project Roles and Responsibilities.
          -------------------------------------------------------------------
Either ZGI or Serono may at its election terminate all (but not less than all)
of its own roles and responsibilities in and with respect to a Development
Project as to a Licensed Product at any time upon [ * ] prior written notice to
the other party; provided, however, that any such election by either party at
any time after the [ * ] will require prior written notice of [ * ] rather than
[ * ].  Any such elective early termination of a party's roles and
responsibilities in such Development Project shall have the effects provided in
Article Twelve below.

                                  ARTICLE FIVE
            Commercialization of Licensed Products in North America

     5.1  Co-Promotion in North America; Election Not to Co-Promote.
          ---------------------------------------------------------

     (a)  Since as a result of its co-promotion of a Licensed Product in North
America ZGI would be entitled to participate in decisions regarding promotion of
such Licensed Product, [ * ] shall only be entitled to [ * ] if, despite [ * ]
having a [ * ] has the ability and commits [ * ] to permit it fully to perform
the [ * ] assigned to it by the [ * ] including at a minimum at least [ * ] of
the anticipated [ * ] with respect to its primary indication(s).  The initial
Commercialization Plan and Budget shall set forth in detail the North American
Co-Promotion Tasks to be allocated to each of ZGI and Serono.  If it is
determined by [ * ] excluding for this [ * ] within [ * ] cannot fulfill the
[ * ] with respect to a [ * ] allocated to it in the [ * ] shall be deemed to
have made an [ * ] with respect to such [ * ]. Neither party shall assign or
delegate a [ * ] allocated to it in the [ * ] without [ * ] in favor of such
assignment or delegation.

     (b)  Subject to subsection (a) above, ZGI and Serono shall co-promote all
Licensed Products in North America, as more fully described in the applicable
Commercialization Plan


[*] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                     -21-
<PAGE>

and Budget, unless and until ZGI elects, as to one or more Licensed Products,
that it will not do so, or that it will no longer do so (an "Election Not to Co-
                                                             -------------------
Promote"). An Election Not to Co-Promote, if any, as to a Licensed Product shall
-------
be made by ZGI by written notice to Serono. Once made, an Election Not to Co-
Promote [ * ] without [ * ]. If no Election Not to Co-Promote is made by ZGI
prior [ * ] of such Licensed Product, then no such Election Not to Co-Promote
may be made by ZGI [ * ] that would have effect prior to the [ * ] following the
date [ * ] is obtained in [ * ] for such Licensed Product (and in any event,
such an Election Not to Co-Promote must be made, if at all, prior [ * ].
Thereafter, ZGI shall be afforded an opportunity prior [ * ] to make an Election
Not to Co-Promote or else to be bound to co-promote pursuant to the applicable
[ * ] for the [ * ].


     5.2  North American Commercialization Costs; Election Not to Co-Fund.
          ---------------------------------------------------------------
Unless and until ZGI elects, as to one or more Licensed Products, that it will
not (or that it will no longer) bear any of the North American Commercialization
Costs with respect to such Licensed Product (an "Election Not to Co-Fund" by
                                                 -----------------------
ZGI), each of Serono and ZGI shall fund and bear fifty percent (50%) of such
North American Commercialization Costs, regardless of which party is allocated
or performs one or more of the relevant North American Co-Promotion Tasks.  An
Election Not to Co-Fund, if any, as to a [ * ] shall be made by ZGI by written
notice to Serono.  Once made, an Election Not to Co-Fund [ * ] as to a [ * ].
An Election Not to Co-Fund shall not be effective with respect to the [ * ]
which it is made, nor as to the immediately following [ * ] but shall become
effective with respect to the second full [ * ] following such Election Not to
Co-Fund.  Unless earlier terminated [ * ] shall terminate upon the date such
[ * ] becomes effective.

     5.3  Selection and Supervision of Personnel.  Each party shall be
          --------------------------------------
responsible for the selection and supervision of its personnel who are assigned
any North American Co-Promotion Tasks pursuant to this Agreement.

     5.4  Third Party Commercial Use Fees.  No amounts paid to [ * ] shall be
          -------------------------------
allowable as part of the [ * ] borne by a party hereto except to the extent that
the same are either paid to a [ * ] or, except for amounts payable by [ * ]
pursuant to Section 10.12, are [ * ] paid pursuant to a [ * ] that is entered
after the Effective Date and with the approval of the [ * ] in accordance with
[ * ]. All other [ * ] including any such amounts payable by [ * ] under the
[ * ] or an [ * ] pursuant to [ * ] if any, shall be borne solely by [ * ] that
is party to the applicable [ * ].

     5.5  Quarterly Accounting and Balancing Payments.  Unless and until ZGI
          -------------------------------------------
has made an Election Not to Co-Fund, the Commercialization Team shall develop
procedures for, and shall implement and coordinate, quarterly accountings and
balancing payments between ZGI and Serono within [ * ] following the end of each
Calendar Quarter, such that each of ZGI and Serono, after such balancing
payments, will on a net basis at least as current as quarterly, bear fifty
percent (50%) of all North American Commercialization Costs.

     5.6  North American Product Term Extension.  Notwithstanding Section 1.60,
          -------------------------------------
the "Product Term" for a Licensed Product in North America shall extend, if
     ------------
later than the end of the period that otherwise would be such term under Section
1.60, until either party makes an Election Not to Co-Fund with respect to that
Licensed Product. Upon any such Election Not to Co-Fund

[*] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                     -22-
<PAGE>

by Serono, subsection 12.2(b) shall apply and upon any such Election Not to Co-
Fund by ZGI, subsection 12.1(b) shall apply. Any such Election Not to Co-Fund
must be made by either party, if at all, by written notice to the other party
prior to August 1 of the year prior to the calendar year as to which it shall
become effective.

                                  ARTICLE SIX
                       Diligence; Adjustment to Territory

     6.1  Responsibility for Commercialization.
          ------------------------------------

     (a)  Serono shall, prior to the effectiveness of an Election Not to Co-
Promote or an Election Not to Co-Fund, either directly or through one or more
Sublicensees or (subject to Section 5.1(a)) Contractors, exert its Reasonable
Commercial Efforts to accomplish the North American Co-Promotion Tasks allocated
to it under the applicable Commercialization Plan and Budget.  ZGI shall, prior
to the effectiveness of an Election Not to Co-Promote or an Election Not to Co-
Fund, either directly or (subject to Section 5.1(a)) through one or more
Contractors,  exert its Reasonable Commercial Efforts to accomplish the North
American Co-Promotion Tasks allocated to it under the applicable
Commercialization Plan and Budget.  Serono shall otherwise, from Regulatory
Approval until the end of the Product Term for each Licensed Product, either
directly or through one or more Sublicensees or Contractors, exert its
Reasonable Commercial Efforts to distribute, market, promote and sell such
Licensed Product in all Marketing Regions in the Territory, and shall exert its
Reasonable Commercial Efforts to maximize the sales of such Licensed Product in
each Marketing Region.

     (b)  As the manufacturer and seller of the Licensed Products, Serono shall
be responsible for making and booking all sales of the Licensed Product in the
Territory.  Serono shall also be responsible for making decisions as to the
pricing or other terms of sale of the Licensed Products, for handling returns or
recalls of the Licensed Product, for interaction with the appropriate Regulatory
Authorities with respect to the Licensed Product and for the maintenance and
provision to such Regulatory Authorities of records and reports with respect to
the Licensed Product as required by applicable law.  For North America, so long
as ZGI has not made an Election Not to Co-Promote or an Election Not to Co-Fund,
Serono shall make such decisions in consultation with the Commercialization Team
in accordance with the Commercialization Plan and Budget.

     (c)  Without limitation on its other responsibilities hereunder, Serono
specifically agrees (subject to Sections 6.3 and 12.2) that it shall, at all
times throughout the Product Term applicable to a Licensed Product, exert
Reasonable Commercial Efforts to have and maintain adequate and available
manufacturing, storage, and shipping facilities; supplies; qualified personnel;
regulatory approvals and registrations; and all other resources required to
manufacture and supply sufficient quantities of such Licensed Product to meet
the then-current and reasonably anticipated marketplace demands for such
Licensed Product in all countries in the Territory in which such Licensed
Product has received Regulatory Approval, and that Serono shall apply the same
to accomplish such manufacture and supply.


[*] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                     -23-
<PAGE>

     6.2  Reports of Sales [ * ].  Following Regulatory Approval for a [ * ] and
          -----------------
unless and until [ * ] with respect to such Licensed Product [ * ] shall provide
the [ * ] reports of the sales of such [ * ] to be submitted on or before the
[ * ], with respect to [ * ] during the preceding [ * ].

     6.3  Early Termination of Commercialization Responsibilities.    Serono may
          -------------------------------------------------------
at its election terminate its roles and responsibilities with respect to the
marketing, distribution and sales of a Licensed Product at any time upon [ * ]
prior written notice to ZGI.  Any such elective termination of such Serono roles
and responsibilities shall have the effects provided in Section 12.2 below.
Serono may make such election to be effective in [ * ] and not otherwise in the
[ * ] provided, however, that if such election to terminate becomes effective in
all of the [ * ] it shall be deemed to be effective [ * ].  If Serono's election
to terminate its roles and responsibilities with respect to the marketing,
distribution and sales of a Licensed Product is effective in [ * ] then:

     (a)  [ * ] in which such elective termination by Serono is effective shall
          thereby be removed from the Territory for such Licensed Product and be
          added to the ZGI Territory;

     (b)  the provisions of subsections (i), (ii), (iii), (vi), and (viii) in
          Section 12.2(a) shall apply, but only to the extent they are
          applicable to such Licensed Product [ * ] in which such elective
          termination by Serono is effective; and

     (c)  Serono shall manufacture and supply such Licensed Product to ZGI [ * ]
          pursuant to subsection (xii) of Section 12.2(a).

                                 ARTICLE SEVEN
                          Initial Fee; Milestone Fees

     7.1  Initial Fee.  In consideration for ZGI's entering into this Agreement
          -----------
and making the license grants hereunder, Serono shall pay to ZGI an initial fee
of [ * ] which amount is non-creditable and payable in accordance with Article
Nine within [ * ] days after execution and delivery of this Agreement.

     7.2  Milestone Fees.  Serono shall in addition pay to ZGI the following
          --------------
amounts (the "Milestone Fees") with respect to the first Licensed Product that
              --------------
achieves the applicable events (the "Milestones") (such payments to be made only
                                     ----------
once with respect to each such Milestone Fee), which amounts are non-creditable,
regardless of whether such Milestone is achieved by Serono, its Affiliates,
Sublicensees or any other marketer authorized by Serono (other than where such a
Milestone is achieved pursuant to a sublicense granted under Section 10.6 and as
to which sublicense royalties are payable as described in Section 8.4):


--------------------------------------------------------------------------------
                Milestone                                Milestone Fee
                ---------                                -------------
--------------------------------------------------------------------------------

                                     [ * ]


[*] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                     -24-
<PAGE>

     7.3  Reporting of Milestones; Payment of Milestone Fees.  Serono shall
          --------------------------------------------------
report to ZGI the occurrence of any Milestone within [ * ] following such
occurrence, and shall pay the applicable Milestone Fee to ZGI in accordance with
Article Nine within [ * ] following the occurrence of the Milestone.

                                 ARTICLE EIGHT
                        Royalty Calculation and Payment

     8.1  Payments to ZGI on North American Net Sales If Co-Fund.  Unless and
          ------------------------------------------------------
until an Election Not to Co-Fund becomes effective for a Licensed Product as
described in Section 5.2, Serono shall pay ZGI [ * ] in North America for such
Licensed Product during the applicable Product Term.

     8.2  Royalties on North American Net Sales If No Co-Fund.  With respect to
          ---------------------------------------------------
any Licensed Product for which an Election Not to Co-Fund by ZGI is effective,
in lieu of [ * ] called for under Section 8.1, Serono shall pay ZGI:

     (a)  [ * ] royalties equal to [ * ] during the applicable Product Term in
          the United States of America or Canada of a Licensed Product whose
          manufacture, use, sale, offer to sell or import would, without a
          license or ownership interest, directly or indirectly infringe one or
          more Patent Claims under any Patent Rights in or to the ZGI Background
          Technology in such country.

     (b)  [ * ] royalties equal to [ * ] during the applicable Product Term in
          the United States of America or Canada of a Licensed Product whose
          manufacture, use, sale, offer to sell or import would, without a
          license or ownership interest, directly or indirectly infringe one or
          more Patent Claims under any Patent Rights in or to any Project
          Technology in such country and would not directly or indirectly
          infringe any Patent Claims under any Patent Rights in or to the ZGI
          Background Technology in such country.

     (c)  Royalties at a rate equal to [ * ] of the rate determined in
          accordance with subsection (a) of the Net Sales during the applicable
          Product Term in the United States of America or Canada of a Licensed
          Product whose manufacture, use, sale, offer to sell or import would
          not infringe any Patent Claims under any Patent Rights in or to the
          ZGI Background Technology or any Project Technology in such country.

     (d)  Royalties equal to any [ * ] paid or payable by [ * ] with respect to
          a [ * ] in the United States of America or Canada during the
          applicable Product Term pursuant to a [ * ] described in [ * ] that is
          entered after the Effective Date and with the approval of [ * ] in
          accordance with [ * ] except for any payment made by [ * ] under [ * ]
          pursuant to [ * ].

Provided, however, that:


[*] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                     -25-
<PAGE>

     (x)  The royalties due to ZGI from Serono pursuant to subsections (a) or
          (b) for each Calendar Quarter, for the United States of America or
          Canada, for Net Sales of each Licensed Product, shall be reduced, in
          the case of royalties payable pursuant to subsection (a), by [ * ]
          and, in the case of royalties payable pursuant to subsection (b), by
          [ * ] of the amount of [ * ] paid or payable by [ * ] (either directly
          or through [ * ] pursuant to subsection (d)) under [ * ] described in
          Section [ * ] for such Calendar Quarter, Licensed Product and country.

     (y)  In no event shall any such royalty payments due to ZGI from Serono
          pursuant to subsections (a) or (b) for a Licensed Product in a country
          be thereby reduced to be [ * ].

     (z)  The royalties in respect of [ * ] of a [ * ] set forth in subsection
          (b) shall be [ * ] to those payable pursuant to subsection (c) in the
          event there is [ * ] from a product, the making, using and selling of
          which does not [ * ] under any [ * ] in or to any [ * ] and which
          contains as its primary active component either [ * ] that is
          substantially the same as the primary active component in the [ * ] or
          the primary active component of which is derived from substantially
          the same [ * ] as the primary active component of the [ * ].  For the
          avoidance of doubt, [ * ] cannot be considered substantially the same
          primary active component as .  For the purpose of this subsection (z),
          competition from such a product shall be deemed to exist in a country
          if (i) the product has received [ * ] to be sold in the country and
          (ii) the product has been [ * ] in the country by a Third Party that
          is not a Sublicensee.

     8.3  Royalties on Rest of World Net Sales.
          ------------------------------------

     With respect to Net Sales of a Licensed Product in the Rest of World Serono
shall pay ZGI:

     (a)  Royalties at a rate determined in accordance with the table set forth
          below on Net Sales during the applicable Exclusivity Period in a
          country of a Licensed Product whose manufacture, use, sale, offer to
          sell or import would, without a license or ownership interest,
          directly or indirectly infringe one or more Patent Claims under any
          Patent Rights in or to the ZGI Background Technology in such country:


     ---------------------------------------------------------------------------
         Net Sales in a calendar year in              Royalty rate for such
         -------------------------------              ---------------------
               Rest of World                                Net Sales
               -------------                                ---------
     ---------------------------------------------------------------------------

                                     [ * ]

     (b)  [ * ] royalties at a rate determined in accordance with the table set
          forth below on Net Sales during the applicable Exclusivity Period in a
          country of a Licensed Product whose manufacture, use, sale, offer to
          sell or import would, without a license or ownership interest,
          directly or indirectly infringe one or more Patent Claims under any
          Patent Rights in or to any Project Technology in such country

[*] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                     -26-
<PAGE>

          and would not directly or indirectly infringe any Patent Claims under
          any Patent Rights in or to the ZGI Background Technology in such
          country:


     ---------------------------------------------------------------------------
         Net Sales in a calendar year in              Royalty rate for such
         -------------------------------              ---------------------
               Rest of World                                Net Sales
               -------------                                ---------
     ---------------------------------------------------------------------------

                                     [ * ]

     (c)  Royalties at a rate equal to [ * ] of the rate determined in
          accordance with the table set forth in subsection (a) on Net Sales of
          a Licensed Product in a country during the applicable Exclusivity
          Period whose manufacture, use, sale, offer to sell or import would not
          directly or indirectly infringe any Patent Claims under any Patent
          Rights in or to the ZGI Background Technology or any Project
          Technology in such country, it being understood that if some of the
          Net Sales of a Licensed Product in the Rest of World would be covered
          by this subsection (c) and other Net Sales of that Licensed Product in
          the Rest of World would be covered by either subsection (a) or (b),
          all such Net Sales shall be aggregated for purposes of determining the
          royalty rates for such Licensed Product in each calendar year as
          described in subsections (a), (b) and (c).

     (d)  Royalties equal to any [ * ] paid or payable by ZGI with respect to a
          [ * ] during the applicable Exclusivity Period pursuant to a Third
          Party Agreement described in Section 1.81 (a) but not (b) that is
          entered after the [ * ] and with the approval of [ * ] in accordance
          with [ * ] except for any payment made by [ * ] under [ * ] pursuant
          to [ * ].

     (e)  The tables for determining royalty rates described in subsections (a),
          (b) and (c) are based on the [ * ] during [ * ] irrespective of
          whether the [ * ] is covered by a particular [ * ] or not (the
          cumulative, annual [ * ] in such tables at which the royalty rates
          change being hereafter referred to as "Breakpoints," i.e., [ * ].
                                                 ------------
          Therefore, for purposes of applying the different royalty rates in
          subsections (a), (b) and (c) in a quarter for a [ * ] sold in various
          countries when the cumulative, annual [ * ] during the quarter has
          passed through a Breakpoint, the [ * ] in a country for the quarter
          shall be apportioned below and above the Breakpoint (for purposes of
          applying the royalty rates) as follows:


          Net Sales below the Breakpoint = [ * ]


          Net Sales above the Breakpoint = [ * ]


          [ * ]


          [ * ].


[*] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                     -27-
<PAGE>

     For ease of calculation, a Licensed Product that changes during a quarter
from being covered by one subsection (i.e., (a), (b) or (c)) to another
subsection shall be deemed to have made the change as of the end of the quarter.
Any [ * ] limitations pursuant to subsections (x) and (y) shall be applied to
the [ * ] and [ * ] Sales apportioned under this subsection (e).

     An example of the calculation pursuant to this subsection (e) for a country
is as follows, assuming [ * ] for the country is first covered by subsection (a)
and during the second quarter changes, and continues to be covered for the rest
of the year, by subsection (b):


                                     [ * ]

     (All figures represent US$ million.)

     The royalty rate in the above example for Q1 was [ * ] as specified in
subsection (a) and for Q3 was [ * ] as specified in subsection (b).  The
royalties due for Q2 and Q4 were calculated as follows:

     [ * ]

     [ * ]

Provided, however, that:

     (x)  The royalties due to ZGI from Serono pursuant to subsections (a) or
          (b) for each Calendar Quarter, for each country, for Net Sales of each
          Licensed Product, [ * ] of the amount of any [ * ] paid or payable by
          [ * ] (either directly or through ZGI pursuant to subsection (d))
          under [ * ] described in [ * ] for such Calendar Quarter, Licensed
          Product and country.

     (y)  In no event shall any such royalty payments due to ZGI from Serono
          pursuant to subsections (a) or (b) for a Licensed Product in a country
          be thereby reduced to be [ * ] those that would be determined by using
          rates equal to [ * ] of the royalty rates set forth in the table in
          subsection (a).

     (z)  The royalties in respect of [ * ] Product in a country set forth in
          subsection (b) shall be [ * ] to those payable pursuant to subsection
          (c) in the event there is [ * ] the making, using and selling of which
          does [ * ] and which contains as its primary active component [ * ].
          For the avoidance of doubt, [ * ] cannot be considered substantially
          the same primary active component as [ * ].  For the purpose of this
          subsection (z), [ * ] from such a product shall be deemed to exist
          [ * ] if (i) the product has received [ * ] to be sold in the country
          and (ii) the product has been [ * ].

     8.4  Royalties on Declined Product Sublicensing Revenues.    Serono shall
          ---------------------------------------------------
pay ZGI royalties equal to [ * ] of the difference obtained by subtracting B
from A, where


[*] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                     -28-
<PAGE>

     A  equals [ * ]

     B  equals [ * ] in connection with the research, development and
        registration of such Declined Product under any Third Party Agreement
        [ * ]

in addition, Serono shall also pay ZGI a sum equal to [ * ] ZGI in connection
with the research, development and registration of such [ * ] paid or payable
[ * ] with respect to such [ * ] under any [ * ] including [ * ].

     8.5  Reporting and Payment.  All amounts and royalties payable under this
          ---------------------
Article Eight shall be due quarterly within [ * ] following the end of each
Calendar Quarter with respect to Net Sales and Declined Product Sublicensing
Revenues in such Calendar Quarter.  Each such payment shall be accompanied by a
statement of Net Sales and Declined Product Sublicensing Revenues for the
quarter on a per Licensed Product and country-by-country basis and the
calculation of the royalties payable hereunder.

                                  ARTICLE NINE
                     Records, Reporting, Payment and Audits

     9.1  Form of Payment; Currency Conversion.  All monies due to ZGI
          ------------------------------------
hereunder shall be paid by wire transfer or other method designated from time to
time by ZGI, in United States Dollars to ZGI in Seattle, WA, USA.  The rate of
exchange to be used shall be the average rate of exchange for the thirty (30)
days preceding the date of payment for the conversion of local currency to
United States Dollars as published by The Wall Street Journal (or if it ceases
to be published, a comparable publication to be agreed upon by the parties) or,
for those countries for which such average exchange rate is not published by The
Wall Street Journal, the exchange rate used by Serono for its own corporate
consolidation purposes.

     9.2  Late Payment.  Without limitation on other available rights or
          ------------
remedies, all amounts payable under this Agreement will bear interest at the
rate of [ * ] per month or the maximum legal rate, whichever is less, from the
date due through the date of payment.

     9.3  Records of Development Costs, North American Commercialization Costs,
          ---------------------------------------------------------------------
and Third Party Royalties.  Both Serono and ZGI shall keep true and accurate
-------------------------
records of revenues, deductions from revenue, expenditures and employees' time
devoted to the collaborative effort undertaken pursuant to this Agreement and
Development Plans and Budgets and Commercialization Plans and Budgets, such that
their Development Costs, North American Commercialization Costs, Third Party
Development Fees, Third Party Commercial Use Fees, Patent Prosecution Costs, and
Patent Defense and Enforcement Costs will be accurately accounted for and
determined hereunder.  Serono shall keep and shall cause its Affiliates and
Sublicensees to keep complete, true and accurate records for the purpose of
showing the derivation of all royalties payable to ZGI under this Agreement.
All such records shall be retained for a period of [ * ] following the end of
the calendar year to which they relate.

     9.4  Records and Audits.  At the other party's request, Serono and ZGI
          ------------------
shall permit such records kept and maintained pursuant hereto to be inspected at
any time during regular


[*] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                     -29-
<PAGE>

business hours, but not more often than once per calendar year, by an
independent public accountant, appointed by the other party for this purpose and
reasonably acceptable to the audited party. The independent public accountant
shall report to the auditing party and the party under audit only its
conclusions regarding the amount of the allowed costs or deductions and/or the
payments due hereunder. The parties shall mutually determine a general strategy
for such audit in advance of its conduct. Any such audit shall be at the expense
of the party requesting the same, unless the audit concludes that, with respect
to the period under audit, the party under audit overstated or understated any
amounts to such an extent that a payment made or called for under this Agreement
(whether to balance the parties' shares of costs or of royalties) was more than
[ * ] in error and in the favor of the party under audit, in which event if such
conclusion is undisputed, the party under audit shall pay or reimburse the
auditing party for the reasonable expenses of such audit. ZGI and Serono agree
that unless covered by one or more exceptions described in Sections 13.2(a) -
(e), all information subject to audit under this Section is confidential and
that it shall cause its accounting firm to retain all such information subject
to the confidentiality restrictions of Article Thirteen hereof.

     9.5  Payments Based on Audit Results.  If the independent public
          -------------------------------
accountant makes an undisputed determination that any amounts to be paid
hereunder have been under-paid or over-paid, the party that benefited therefrom
shall promptly make a payment to the other party such that all amounts paid
hereunder shall conform to the amounts so determined to be payable.

     9.6  Withholding.  Other than with respect to those matters described in
          -----------
Section 9.7 hereof which are covered by the terms and conditions set forth
therein, if any amounts are required to be withheld or any taxes are required to
be paid on behalf of, or with respect to, any party hereto by reason of any
payment to such party by the other party, the payor may withhold such amounts
and make the tax payments so required.  All such tax payments made on behalf of
a party shall be considered to be paid to such party for purposes of this
Agreement.  The party withholding the same shall promptly secure and deliver to
the other party appropriate official receipts for the taxes withheld and other
documents necessary to enable such other party to claim appropriate foreign tax
credits for such taxes paid.

     [ * ]

     (a)  The parties intend that none of the activities contemplated under this
Agreement will create or constitute a [ * ] foreign (including the European
Union and comparable entities) or other [ * ].  However, if any such activities
are, pursuant to a [ * ], determined to constitute [ * ] for such purposes, ZGI
and Serono agree to cooperate in providing all consents, elections, signatures,
information, and documents as may be reasonably required in the circumstances,
including any action reasonably required to effectuate the rights of Serono (or
its successors or transferree) pursuant to paragraphs (c) or (d) below. [ * ]

     (b)  If any [ * ] initiates an [ * ] in which it is asserted that the
activities hereunder, or any subset of such activities, create a [ * ] shall
control the defense of such [ * ] (or portion thereof in the event the [ * ]
involves other issues and such deemed [ * ] may be severed), shall have the sole
right to settle such [ * ] with the consent of [ * ] (which consent shall not be
unreasonably withheld), and shall in its discretion make [ * ] with respect
thereto.  All such [ * ]


[*] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                     -30-
<PAGE>

made on behalf of a party or that reduce an underlying [ * ] of a party shall be
considered to be paid to such party for purposes of this Agreement. The burden
of any other [ * ] shall be allocated between the parties as appropriate by [ *
]. If Serono [ * ] on behalf of the [ * ] Serono shall promptly secure and
deliver to [ * ] customary documents that may be reasonably required for [ * ]
to [ * ] (if any) with respect to such [ * ].

     (c)   If, pursuant to a [ * ], it is determined that the activities
hereunder, or any subset of such activities, create a [ * ] for any [ * ] (or
its successor or transferee) shall have the sole right to prepare and file [ * ]
in any jurisdiction in which the [ * ] may be required to file a [ * ], and
shall have the sole right to make any [ * ] under applicable law for such [ * ]
provided that if the [ * ] would have a reasonably foreseeable material adverse
effect on [ * ] shall first obtain the consent of [ * ] or its successor or
transferee) shall, to the extent such election is available, elect under [ * ]
to cause the [ * ] to be subject to the provisions of [ * ] shall be the [ * ]
within the meaning of [ * ]), and shall have full power and authority to act as
such.

     (d)   If, pursuant to a [ * ], it is determined that the activities created
hereunder, or any subset of such activities, create a [ * ] for any [ * ], or if
[ * ] reasonably believes such a [ * ] is likely, [ * ] (or its successor or
transferee) shall, subject to the provisions of Section 19.6, have the right,
exercisable at any time[ * ] shall [ * ]; provided, however, that the rights
                                          --------  -------
responsibilities of [ * ] shall conform as nearly as possible, mutatis mutandis,
                                                               ----------------
to the rights and responsibilities of [ * ] respectively, [ * ].

     (e)   The parties shall indemnify and hold each other and their respective
representatives harmless from and against any liabilities with respect to any
failure to effect [ * ] pursuant to this Section 9.7[ * ]. If any penalties are
imposed upon either ZGI or Serono for [ * ], the burden thereof shall be
allocated between the parties as appropriate by [ * ]. The parties shall
cooperate to minimize any such [ * ] to the extent possible.

                                  ARTICLE TEN

                       Intellectual Properties; Licenses

     10.1    Ownership of Intellectual Properties.    ZGI shall own any and all
             ------------------------------------
intellectual property covering ZGI Project Technology, Serono shall own any and
all intellectual property covering Serono Project Technology, and ZGI and Serono
shall jointly own any and all intellectual property covering Joint Project
Technology, in each case subject to the licenses granted hereunder.  Serono
shall own the intellectual property covering the Licensed Product Trademarks.
Serono agrees to the extent practicable to select a single worldwide trademark
for each Licensed Product.  The parties agree that the laws and rights
applicable under U.S. law with respect to the joint ownership of patents and
inventions shall also be applied in other nations giving effect to this
Agreement, subject to the licenses granted hereunder.  Except for the rights
expressly granted under Section 2.2, in this Article Ten, or pursuant to Article
Twelve, no right, option or license is granted or implied to Serono or ZGI,
under any patent or other intellectual property or to any other product, in any
field, or in any geographic territory.  Neither party makes any grant of rights
by implication.

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed seperately with the Commission

                                      -31-
<PAGE>

     10.2    Development Project Licenses.    Serono hereby grants to ZGI a
             ----------------------------
worldwide, royalty-free license, with right to sublicense to Contractors, to
practice and use the Serono Project Technology for research and development
purposes within the scope of ZGI's Development Tasks during and in the course of
any Development Project.  In addition, Serono hereby irrevocably covenants to
refrain from and to cause its Affiliates to refrain from, directly or
indirectly, asserting any claim or demand, or commencing, instituting or causing
to be commenced, any proceeding of any kind against ZGI, its Affiliates or
Contractors based upon any infringement or alleged infringement of Serono
Background Technology by such person in connection with their activities within
the scope of ZGI's Development Tasks during and in the course of any Development
Project.

     10.3    Co-Promotion Licenses.    Unless and until any Election Not to Co-
             ---------------------
Promote or Election Not to Co-Fund made by ZGI becomes effective, Serono hereby
grants to ZGI a nonexclusive, royalty-free license, with right to sublicense to
Contractors, to the Licensed Product Trademark and to practice and use the
Serono Project Technology in the performance of its North American Co-Promotion
Tasks.

     10.4    License to Serono in the Territory. ZGI hereby grants to Serono a
             ----------------------------------
royalty-bearing license under the ZGI IP, Ig Fusion Technology and ZGI's
interest in Joint Project Technology to make, have made, use, sell, offer to
sell, and import Licensed Products in the Territory during the Product Term
applicable to each such Licensed Product. Subject to:

     (a)     ZGI's retained rights to practice and use the ZGI IP, Ig Fusion
             Technology and ZGI's interest in the Joint Project Technology
             within the scope of ZGI's Development Tasks;

     (b)     ZGI's retained rights to practice and use the ZGI IP, Ig Fusion
             Technology and ZGI's interest in the Joint Project Technology to
             perform its North American Co-Promotion Tasks; and

     (c)     with respect to the Background Technology licensed under the St.
             Jude License Agreement, the rights retained by the U.S. government
             and the academic research and educational use rights retained by
             St. Jude Children's Research Hospital and other researchers, all as
             described in the St. Jude License Agreement,

such license shall be exclusive in a country during the Exclusivity Period
applicable to such country for such Licensed Product, and shall otherwise be
nonexclusive.

     10.5    Sublicenses as to Licensed Products.
             -----------------------------------

     (a)     Serono shall have the right to grant sublicenses under the license
granted in Section 10.4 as to Licensed Products (other than Declined Products)
in the Rest of World; provided, however, that any such sublicense:

     (i)     shall provide that it is subject to and shall be governed by this
             Agreement and that the Sublicensee shall conform to all of Serono's
             obligations hereunder;

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed seperately with the Commission

                                      -32-
<PAGE>

     (ii)    shall be disclosed to ZGI in its entirety, subject to ZGI's
             obligations under Article Thirteen to the extent applicable
             thereto; and

     (iii)   shall provide that, upon any removal from the Territory pursuant
             hereto of any country covered by such sublicense, ZGI may at its
             option (but shall not be required to) continue such sublicense in
             effect in the ZGI Territory, with ZGI substituted thereunder in
             place of Serono.

     (b)     Serono shall have the right to grant sublicenses under the license
granted in Section 10.4 as to Licensed Products (other than Declined Products)
in North America; provided, however, that any such sublicense conforms to
clauses (i) - (iii) of subsection 10.5(a) and, unless an Election Not to Co-Fund
made by ZGI with respect to the applicable Licensed Product has become
effective, that Serono has obtained ZGI's prior written consent to such
sublicense, which consent shall not be unreasonably withheld or delayed.

     10.6    Declined Products Sublicenses.    Serono shall have the right to
             -----------------------------
grant anywhere in the Territory sublicenses under the license granted in Section
10.4 to make, have made, use, sell, offer to sell, and import Declined Products;
provided, however, that any such sublicense conforms to clauses (i) - (iii) of
subsection 10.5(a) and that Serono has obtained ZGI's prior written consent to
such sublicense, which consent shall not be unreasonably withheld or delayed.

     10.7    License to ZGI in ZGI Territory.    Serono hereby grants to ZGI a
             -------------------------------
royalty-bearing license under the Serono Project Technology and Serono's
interest in the Joint Project Technology and the Licensed Product Trademarks to
make, have made, use, sell, offer to sell, and import Licensed Products in the
ZGI Territory, if any, during the Product Term applicable to such Licensed
Product.  Such license shall be exclusive in a country during the Exclusivity
Period applicable to such country for such Licensed Product (treating, for this
purpose, references in Section 1.32 to ZGI IP as being references instead to
Serono Project Technology), and shall otherwise be nonexclusive.

     10.8    Sublicenses.    ZGI shall have the right to grant sublicenses under
             -----------
the license granted in Section 10.7; provided, however, that any such
sublicense:

     (a)     shall provide that it is subject to and shall be governed by this
             Agreement and that the Sublicensee shall conform to all of ZGI's
             obligations hereunder; and

     (b)     shall be disclosed to Serono in its entirety, subject to Serono's
             obligations under Article Thirteen to the extent applicable
             thereto.

     10.9    Patent Marking. Each party agrees to mark with notices of patent,
             --------------
and to have so marked by its Affiliates and Sublicensees, every marketed
Licensed Product, in accordance with the laws of the United States of America or
other applicable countries relating to the marking of patented articles.

     10.10   Trademark License Quality Controls.    Each party, as a licensee
             ----------------------------------
hereunder with respect to any trademark or service mark, agrees to abide by
reasonable quality control and

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed seperately with the Commission

                                      -33-
<PAGE>

labeling and usage standards and procedures, such as periodic rights to inspect
goods, services, packaging, and advertising provided with or under such mark, as
may be requested by the licensor of such mark, subject to the approval of such
standards and procedures by Steering Committee Action.

     10.11   St. Jude License Agreement. Certain license rights granted to [ * ]
             --------------------------
include a [ * ] of [ * ] under the St. Jude License Agreement. Notwithstanding
the provisions of such [ * ] and any other provisions of this Agreement, [ * ]
shall, in exercising such [ * ] (a) comply with, perform in accordance with, and
be subject to Sections [ * ] relating to [ * ] and (b) at the request of [ * ]
provide information and other assistance to [ * ] ZGI to comply and perform in
accordance with Sections 3.1, 5.1 and 5.2 of the [ * ] relating to [ * ].

     10.12   Existing Third Party Agreements.    ZGI shall be responsible for
             -------------------------------
making and, in the event that in order to commercialize a Licensed Product
Serono requires a license to the technology that is licensed under the
agreements with [ * ] listed in Exhibit 1.34 and a Third Party Agreement as
described within Section 1.81(a) but not (b) is entered into with either of such
Third Parties with respect to such technology (an "Existing Third Party
                                                   --------------------
Agreement Replacement"), all payments under any such Existing Third Party
---------------------
Agreement Replacement; provided that [ * ] shall not be obliged to pay an amount
under any [ * ] that is [ * ] than the amount ZGI would be obliged to pay under
the relevant [ * ] as it is drafted as of the Effective Date.  ZGI shall not
commit any acts or omissions that would cause a breach of any Existing Third
Party Agreement such that the relevant Third Party would be entitled to
terminate the Existing Third Party Agreement and will not exercise any rights of
termination it may have with respect to any of the Existing Third Party
Agreements without the prior written consent of Serono, which consent shall not
be unreasonably withheld.

                                ARTICLE ELEVEN

               Patent and Trademark Prosecution and Enforcement

     11.1  Ig Fusion Technology.
           --------------------

     ZGI shall be solely responsible, as it shall determine and at its own
expense, for the filing and prosecution of the Ig Fusion Technology, for
opposition or interference proceedings with respect thereto, and for the
maintenance, enforcement and defense of any available patent protection with
respect thereto; provided that if ZGI files suit alleging infringement of a
patent included in the Ig Fusion Technology and the allegedly infringing product
includes [ * ] Serono shall have the right to join such suit.  If ZGI prevails
in an infringement action under the Patent Rights within the Ig Fusion
Technology against a Third Party in respect to a product that includes [ * ]
then any damages awarded to and recovered by ZGI shall be [ * ] as described in
[ * ] without reference to [ * ].

     11.2    St. Jude Patent Rights.
             ----------------------

     ZGI's rights to prosecute, maintain, enforce and defend the Patent Rights
included in the St. Jude License Agreement are stated in the St. Jude License
Agreement.  ZGI shall provide Serono's Patent Contact with the opportunity to
review and comment on prosecution and

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed seperately with the Commission

                                      -34-
<PAGE>

maintenance of such Patent Rights to the extent that ZGI is actually provided
the opportunity to review and comment on prosecution and maintenance of such
Patent Rights. ZGI's and Serono's rights to enforce and defend such Patent
Rights shall be governed by Section 11.4 below. ZGI shall not elect to cease
reimbursing [ * ] expenses associated with obtaining or maintaining patent
protection for a Patent Right in a country (as contemplated by [ * ] without
first offering in writing to Serono the opportunity to make such reimbursement,
whether directly or indirectly through [ * ]. If, within [ * ] of its receipt of
an offer pursuant to the forgoing sentence, Serono does not indicate in writing
its desire to [ * ] in respect of the relevant Patent Right and country, [ * ]
shall be free to make the election contemplated by [ * ] with respect to that
Patent Right and country and, effective as of [ * ], such Patent Right shall be
deemed a Discontinued Patent (as described in Section 11.3(d)) with respect to
the relevant country.

     11.3    Prosecution and Maintenance.
             ---------------------------

     (a)     ZGI Background Technology (Other Than Under St. Jude License
             -------------------------
Agreement) and ZGI Project Technology. ZGI shall be solely responsible, as it
-------------------------------------
shall determine [ * ], for the filing and prosecution of any and all patent
applications with respect, in whole or in part, to any ZGI Background Technology
(other than Patent Rights included in the St. Jude License Agreement) and ZGI
Project Technology, for opposition or interference proceedings with respect
thereto, and for the maintenance of any available patent protection with respect
thereto. For purposes of this Article 11 and with respect to ZGI Background
Technology (other than Patent Rights included in the St. Jude License Agreement)
and ZGI Project Technology, ZGI shall be the "Patent Prosecution Party".

     (b)     Serono Project Technology. Serono shall be solely responsible, as
             -------------------------
it shall determine [ * ], for the filing and prosecution of any and all patent
applications with respect, in whole or in part, to any Serono Project
Technology, for opposition or interference proceedings with respect thereto, and
for the maintenance of any available patent protection with respect thereto. For
purposes of this Article 11 and with respect to Serono Project Technology,
Serono shall be the "Patent Prosecution Party".

     (c)     Joint Project Technology. ZGI and Serono shall share
             ------------------------
responsibilities with regard to patent matters relating to Joint Project
Technology, [ * ]. The Patent Contacts shall be responsible for assigning
specific tasks to each of the parties with respect to the filing and prosecution
of any and all patent applications with respect, in whole or in part, to any
such Joint Project Technology, for opposition or interference proceedings with
respect thereto, and for the maintenance of any available patent protection with
respect thereto. For each such patent application or proceeding, the Patent
Contacts shall designate whether ZGI or Serono is the "Patent Prosecution
Party".

     (d)     Patent Prosecution Party's Efforts.  For each patent application,
             ----------------------------------
patent and proceeding described in this Section 11.3, the Patent Prosecution
Party shall exert its Reasonable Commercial Efforts, consistent with its
customary practices, with respect to its activities, to the extent such
activities bear on Licensed Products. In particular, the Patent Prosecution
Party shall: deliver to the other party copies of communications between the
Patent Prosecution Party and relevant patent offices, promptly after receipt
from, or delivery to, such patent office; take the


[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed seperately with the Commission

                                      -35-
<PAGE>

other party's comments and suggestions into consideration when framing responses
and submissions to patent offices; provided that the Patent Prosecution Party
shall have no obligation to solicit comments or suggestions from the other
party, and provided that the Patent Prosecution Party shall have final authority
over the content of responses and submissions to patent offices. A Patent
Prosecution Party may, at any time, elect, by written notice to the other party,
to discontinue support for one or more patents or patent applications (a
"Discontinued Patent") and shall not be responsible for any costs relating to a
 -------------------
Discontinued Patent that are incurred more than sixty (60) days after receipt of
that notice by the other party. In such case, and so long as the other party is
not in default under this Agreement, the other party may elect, at its sole
discretion, to continue preparation, filing, prosecution and/or maintenance of
the Discontinued Patent at its sole expense. The party so continuing shall own
any such Discontinued Patent, and the party electing to discontinue support
shall execute such documents of transfer or assignment and perform such acts as
may be reasonably necessary to transfer sole ownership of the Discontinued
Patent to the other party and enable that party to file or to continue
prosecution or maintenance of the Discontinued Patent, if the other party elects
to do so. In the event that Serono continues a Discontinued Patent for which ZGI
is the Patent Prosecution Party, such Discontinued Patent shall not be
considered as included in Patent Rights in or to any ZGI Background Technology
or Project Technology for the purpose of calculating royalties under Sections
8.2(a) or (b) and 8.3(a) or (b).

     11.4    Defense and Enforcement Actions.
             -------------------------------

     (a)     Notification.  During the Product Term, each party shall notify the
             ------------
other party of any attack on the validity or enforceability of any Patent Rights
within the ZGI Background Technology or the Project Technology, or of any
infringement of any such Patent Rights, or of any certification filed under the
U.S. Drug Price Competition and Patent Term Restoration Act of 1984 claiming
that any patent within the ZGI Background Technology or Project Technology is
invalid or that infringement will not arise from the manufacture, use or sale of
any product by a Third Party, as soon as reasonably practicable after it becomes
aware of such attack, infringement or certification.  After [ * ] with each
other[ * ] Contacts shall make a recommendation to [ * ] may decide to pursue
the Third Party jointly under mutually agreeable conditions.  In the absence of
a [ * ] to do otherwise or in the event that [ * ] cannot decide on a course of
action (as to which the provisions of Article 18 shall not apply), the following
provisions shall control.

     (b)     Parties' Roles.  [ * ], and Serono in the case of Joint Project
             --------------
Technology, shall have the primary right, but not the obligation, to take action
with regard to a suspected infringer or party claiming invalidity, including
sending a cease and desist letter or filing a legal action.  If the patent owner
(or [ * ] in the case of Joint Project Technology) files such an action, it
shall have the right to control such lawsuit and be represented by counsel of
its choosing, at its own expense; and the other party shall have the right, at
its own expense, to be represented in such action by its own counsel.  If the
patent owner (or [ * ] in the case of Joint Project Technology) fails to take
such action within [ * ] after receiving notice of the infringement or
invalidity claim, or [ * ] after the filing date of such a certification under
the U.S. Drug Price Competition and Patent Term Restoration Act of 1984, and if
the other party is not in default under this Agreement, then [ * ] party shall
have the right to take such action, by counsel of its own choice

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed seperately with the Commission

                                      -36-
<PAGE>

and at its own expense. In such case, if [ * ] is required to join the action as
a necessary party, [ * ] shall pay for the [ * ] and shall [ * ] from claims by
the other party to the lawsuit (e.g., the infringer). Each party shall provide [
* ] and shall execute [ * ] necessary for the prosecution of such suit as may be
[ * ] requested by the party bringing suit. No settlement or consent judgment or
other voluntary final disposition of a suit under this Section 11.4 may be
entered into without [ * ] which consent shall [ * ].

     (c)  Sharing of awards.  Any award of damages granted in a legal proceeding
          -----------------
covered by this Article 11 shall be used to reimburse [ * ] and [ * ] if it was
required to join as a necessary party, for [ * ].

     (i)  Except as provided in (ii) and (iii) below, the remainder of any such
          award of damages shall be shared as follows:

          (A)  damages attributable to the infringer's sales [ * ] America shall
               be [ * ] between ZGI and Serono, unless [ * ] in which case, the
               damages shall be [ * ];

          (B)  damages attributable to the infringer's sales [ * ] shall be
               [ * ].

    (ii)  If the damages were awarded in a suit where [ * ] as the patent owner,
          within the applicable prescribed time period, then [ * ] of the
          damages remaining after reimbursement of legal costs shall be [ * ].

    (iii) If the damages were awarded in a suit where [ * ] as the patent
          owner or with regard to [ * ] within the applicable prescribed time
          period, then [ * ] of the damages remaining after reimbursement of
          legal costs shall be [ * ].

    11.5  Patent Extensions.
          -----------------

    The parties shall cooperate in seeking any available extension of the term
of any Patent Rights in and to the ZGI IP, the Serono IP or the Joint Project
Technology. Such cooperation shall include: (a) advising each other in a timely
manner of any action by any Regulatory Agency that is pertinent to any such
extension; (b) reasonably supplying each other with all information in its
control pertaining to the extension of any such Patent Rights; and (c)
cooperating with each other to execute all supporting affidavits or documents
required in connection with the extension of any such Patent Rights.

    11.6  Protection of the Licensed Product Trademarks.
          ---------------------------------------------

    [ * ] shall at its expense be responsible for the registration, proper use,
defense and enforcement of the Licensed Product Trademarks, and [ * ] own the
rights to such Licensed Product Trademarks, subject to this Agreement.


[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed seperately with the Commission

                                      -37-
<PAGE>

                                ARTICLE TWELVE

          Elective Termination of Certain Roles and Responsibilities

     12.1  Termination at Election of ZGI.
           ------------------------------

     (a)   If ZGI elects to terminate its roles and responsibilities under the
Development Project for a Licensed Product pursuant to Section 4.8, the
following will apply with respect to the Licensed Product involved:

     (i)   Article Three shall no longer apply with respect to the Licensed
           Product involved, and Serono shall take over all control and decision
           making roles with respect to further Development Project activities
           and marketing, distribution and sales activities with respect to any
           such Licensed Product;

     (ii)  notwithstanding any provision of Article Eleven to the contrary,
           Serono shall at its expense have control over the prosecution,
           maintenance, defense and enforcement of Patent Rights in and to
           Project Technology that covers only such Licensed Product; provided,
           however, that if Serono elects to abandon any patent or trademark
           application or not to defend or enforce (or not to continue to
           attempt to defend or enforce) any such Patent Rights or the Licensed
           Product Trademarks applicable only to such Licensed Product, it shall
           promptly so inform ZGI in sufficient time that ZGI may at its
           election continue to prosecute such application or bring (or
           continue) such enforcement action at ZGI's risk and expense;

     (iii) the trademark and service mark quality control and labeling and usage
           standards and procedures referred to in Section 10.10 with respect to
           any trademarks or service marks applicable only to such Licensed
           Product shall no longer be subject to approval by Steering Committee
           Action;

     (iv)  ZGI will have no further responsibility to conduct or to assist with
           any Development Tasks with respect to such Licensed Product, although
           it will cooperate reasonably with Serono at Serono's expense to
           transition any then on-going Development Tasks conducted by ZGI with
           respect to such Licensed Product to Serono for use within the scope
           of the Development Project;

     (v)   ZGI shall have [ * ] further obligation to [ * ] with respect to such
           [ * ] and Serono shall fund and bear [ * ] of the same to the extent
           incurred from the effectiveness of such termination by ZGI forward;
           provided, however, that [ * ] will continue to be responsible for
           making all payments under [ * ] pursuant to [ * ] and will, at
           Serono's request [ * ] any [ * ] to which it is a party and which
           were approved by [ * ] pursuant to [ * ] to the extent such [ * ] can
           be so [ * ];

     (vi)  the licenses granted by [ * ] with respect to such [ * ] shall [ * ]
           for the duration of [ * ] as stated in such Article for such
           licenses, respectively, and subject to [ * ] obligations under this
           Agreement with respect to such Licensed Product;

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed seperately with the Commission

                                      -38-
<PAGE>

     (vii)   Serono's obligation under Section 2.1 shall not continue with
             respect to the Licensed Product;

     (viii)  ZGI will be deemed to have made an Election Not to Co-Promote with
             respect to such Licensed Product;

     (ix)    ZGI will be deemed to have made an Election Not to Co-Fund with
             respect to such Licensed Product;

     (x)     Serono's obligations hereunder, including those with respect to
             Milestone Fees under Section 7.2, as to royalties on Declined
             Product Sublicensing Revenues under Section 8.4, and as to
             diligence under Sections 4.1 and 6.1 shall continue in effect
             hereunder as limitations upon and conditions to the licenses to it
             hereunder throughout the applicable Product Term;

     (xi)    Royalties under Section 8.2(a) shall be determined in accordance
             with the royalty rates set forth in the following tables and for
             the purpose of applying such royalty rates Net Sales shall be
             allocated in the same manner as set forth in Section 8.3(e):

             (A)  If the termination of ZGI's roles and responsibilities with
                  respect to a Licensed Product pursuant to Section 4.8 becomes
                  effective after the [ * ] of that Licensed Product and before
                  the submission of [ * ] then the following royalty rates shall
                  apply:


     ---------------------------------------------------------------------------
              Net Sales in a calendar year in            Royalty rate for such
              -------------------------------            ---------------------
                       North America                             Net Sales
                       -------------                             ---------
     ---------------------------------------------------------------------------

                                     [ * ]

          (B)  If the termination of ZGI's roles and responsibilities with
               respect to a Licensed Product pursuant to Section 4.8 becomes
               effective prior to [ * ] of that Licensed Product, then the
               following royalty rates shall apply:

      --------------------------------------------------------------------------
             Net Sales in a calendar year in              Royalty rate for such
             -------------------------------              ----------------------
                      North America                                  Net Sales
                      -------------                                  ---------
      --------------------------------------------------------------------------

                                           [ * ]

     (xii)  Royalties under Section 8.2(b) shall be determined in accordance the
            royalty rates set forth in the following tables and for the purpose
            of applying such royalty rates Net Sales shall be allocated in the
            same manner as set forth in Section 8.3(e):

            (A)  If the termination of ZGI's roles and responsibilities with
                 respect to a Licensed Product pursuant to Section 4.8 becomes
                 effective after the Initiation of [ * ] of that Licensed
                 Product and before the submission of [ * ] then the following
                 royalty rates shall apply:

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed seperately with the Commission.

                                      -39-
<PAGE>

               Initiation of [ * ] of that Licensed Product and before the
               submission of [ * ] then the following royalty rates shall apply:

      --------------------------------------------------------------------------
             Net Sales in a calendar year in              Royalty rate for such
             -------------------------------              ----------------------
                      North America                                  Net Sales
                      -------------                                  ---------
      --------------------------------------------------------------------------

                                     [ * ]

          (B)  If the termination of ZGI's roles and responsibilities with
               respect to a Licensed Product pursuant to Section 4.8 becomes
               effective prior to the Initiation of [ * ] of that Licensed
               Product, then the following royalty rates shall apply:

      --------------------------------------------------------------------------
             Net Sales in a calendar year in              Royalty rate for such
             -------------------------------              ----------------------
                      North America                                  Net Sales
                      -------------                                  ---------
      --------------------------------------------------------------------------

                                     [ * ]

     (xiii)  If the termination of ZGI's roles and responsibilities with respect
             to a Licensed Product pursuant to Section 4.8 becomes effective
             prior to the Initiation of [ * ] of that Licensed Product, then for
             the purpose of calculating royalties under Section 8.3(b) the table
             set forth in such Section shall be replaced with the table set
             forth below:


      --------------------------------------------------------------------------
             Net Sales in a calendar year in              Royalty rate for such
             -------------------------------              ----------------------
                     Rest of World                                   Net Sales
                     -------------                                   ---------
      --------------------------------------------------------------------------

                                     [ * ]

     (b) It is further agreed, for the avoidance of doubt, that if [ * ] does
not [ * ] its role and responsibilities under the Development Project for a
Licensed Product prior to the end of the Development Project Term for that
Licensed Product pursuant to [ * ] the provisions of subsection (a) above will
not apply.  Rather, any [ * ] of its roles and responsibilities made by [ * ]
from that point forward as to that Licensed Product will be deemed to be [ * ].
Furthermore, if [ * ] makes an [ * ] as to a Licensed Product in North America
following the end of the Product Term for such Licensed Product in North America
(determined under Section 1.60 without regard to Section 5.6), the provisions of
subsection (a) above will also not apply; rather, such [ * ] will terminate the
[ * ] for such Licensed Product in North America and the applicability of
Articles Three, Five, Six, Eight, Nine, and Eleven to such Licensed Product in
North America, and in lieu thereof, the provisions of [ * ] shall apply as to
that Licensed Product in North America.

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed seperately with the Commission.

                                      -40-
<PAGE>

     12.2   Termination at Election of Serono.
            ---------------------------------

     (a)    If Serono elects to terminate its roles and responsibilities under
the Development Project for a Licensed Product pursuant to Section 4.8, or if
Serono elects to terminate its roles and responsibilities with respect the
marketing, distribution and sales of a Licensed Product pursuant to Section 6.3,
the following will apply with respect to the Licensed Product involved:

     (i)    Article Three shall no longer apply with respect to the Licensed
            Product involved, and ZGI shall take over all control and decision
            making roles with respect to further Development Project activities
            and marketing, distribution and sales activities with respect to any
            such Licensed Product;

     (ii)   notwithstanding any provision of Article Eleven to the contrary, ZGI
            shall at its expense have control over the prosecution, maintenance,
            defense and enforcement of Patent Rights in and to Project
            Technology covering only such Licensed Product and over the use,
            registration and protection of the Licensed Product Trademarks
            applicable only to such Licensed Product; provided, however, that if
            ZGI elects to abandon any patent or trademark application or not to
            defend or enforce (or not to continue to attempt to defend or
            enforce) any such Patent Rights or Licensed Product Trademarks, it
            shall promptly so inform Serono in sufficient time that Serono may
            at its election continue to prosecute such application or bring (or
            continue) such enforcement action at Serono's risk and expense;

     (iii)  the trademark and service mark quality control and labeling and
            usage standards and procedures referred to in Section 10.10 with
            respect to any trademarks or service marks applicable only to such
            Licensed Product shall no longer be subject to approval by Steering
            Committee Action, but nevertheless, to the extent applicable to such
            Serono trademarks and service marks licensed to ZGI, shall be only
            such as are commercially reasonable and necessary to preserve
            Serono's rights as licensor of any such mark;

     (iv)   with respect to such a termination under Section 4.8 regarding a
            Licensed Product, Serono will have no further responsibility to
            conduct or to assist with any Development Tasks with respect to such
            Licensed Product, although it will cooperate reasonably with ZGI at
            ZGI's expense to transition any then on-going Development Tasks
            conducted by or on behalf of Serono with respect to such Licensed
            Product to ZGI for use within the scope of the Development Project;

     (v)    with respect to such a termination under Section 4.8 regarding a
            Licensed Product, Serono shall [ * ] with respect to [ * ], and ZGI
            shall fund and bear [ * ] of the same to the extent incurred from
            the effectiveness of such termination by Serono forward; provided,
            however, that Serono will, at ZGI's request, [ * ] any [ * ] to
            which it is a party and which were approved by [ * ] pursuant to
            [ * ] to the extent such [ * ] can be so transferred;


[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -41-
<PAGE>

     (vi)    with respect to such a termination under [ * ] regarding a [ * ]
             shall have no further role or responsibility for the marketing,
             distribution or sales of that [ * ] nor any obligation to [ * ]
             with respect thereto; provided, however, that Serono will, at ZGI's
             request, [ * ] any [ * ] to which it is a party and which were
             approved by [ * ] pursuant to [ * ] to the extent [ * ] can be so
             [ * ];

     (vii)   all countries in the world shall automatically thereby be removed
             from the Territory and shall become part of the ZGI Territory with
             respect to that Licensed Product;

     (viii)  Serono shall have no further obligation to pay Milestone Fees with
             respect to that Licensed Product pursuant to Section 7.2 hereof;

     (ix)    the licenses granted by Serono to ZGI under Article Ten with
             respect to such Licensed Product shall continue in effect for the
             duration of the Development Project Term or the Product Term, as
             stated in such Article for such licenses, respectively, and subject
             to ZGI's obligations under this Agreement with respect to such
             Licensed Product; provided, however, that the license to ZGI under
             Section 10.7 shall be expanded to include [ * ] and shall be on
             financial terms and conditions that are [ * ] (which terms and
             conditions shall either be [ * ] or shall be [ * ];

     (x)     ZGI's obligation under Section 2.1 shall not continue with respect
             to the Licensed Product;

     (xi)    if the termination of Serono's Development Project roles and
             responsibilities pursuant to Section 4.8 with respect to a Licensed
             Product first becomes effective prior to the Initiation of [ * ] of
             such Licensed Product, then the following shall apply with respect
             to such Licensed Product:

             (A)  if and to the extent that any [ * ] in existence on the
                  effective date of such termination that is applicable to such
                  [ * ] is not already covered by [ * ] under [ * ], the same
                  shall hereby be deemed to be included in such [ * ] on a [ * ]
                  and

             (B)  [ * ] shall promptly provide to [ * ] a full disclosure of all
                  [ * ], if any, that shall not have prior thereto been provided
                  to [ * ] to the extent the same is reasonably necessary to
                  enable [ * ] for use in the [ * ]; and

     (xii)   if the termination of Serono's Development Project roles and
             responsibilities pursuant to Section 4.8 with respect to a Licensed
             Product or if the termination of Serono's roles and
             responsibilities with respect to the marketing, distribution and
             sales of a Licensed Product pursuant to Section 6.3 first becomes
             effective at any time after [ * ] then the following shall apply
             with respect to such Licensed Product:

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -42-
<PAGE>

          (A)  Serono shall transfer to ZGI all then-existing clinical and
               commercial stocks of the Licensed Product, and shall also
               complete any on-going manufacturing runs and supply the Licensed
               Product made in such runs to ZGI, in each such case [ * ] except
               with respect to stocks or manufacturing runs the costs of which
               were or are to be included in the quarterly accountings and
               balancing payments called for under either Section 4.6 or Section
               5.5 (which stocks and manufacturing runs shall be provided by
               Serono under this clause without any further charge to ZGI,
               except as provided for in Section 4.6 or Section 5.5);

          (B)  to the extent supplies in addition to those to be provided under
               clause (A) above are required, Serono shall, at all times between
               the effectiveness of its termination of such roles and
               responsibilities pursuant to Section 4.8 or 6.3 and [ * ]
               manufacture and supply to ZGI all of ZGI's and its Affiliates'
               and Sublicensees' worldwide requirements for the Licensed
               Product, provided such requirements do not exceed [ * ] of the
               requirements for the Licensed Product for that period described
               in the Development Plan and Budget.  ZGI shall [ * ] to find and
               qualify an alternative manufacturing source for such Licensed
               Product as promptly as possible, and, unless ZGI terminates this
               supply arrangement earlier at its option, ZGI [ * ], shall
               purchase all of such requirements from Serono, which Licensed
               Products will be supplied pursuant to a supply agreement that is
               [ * ] (which shall either be [ * ], or shall be determined [ * ]
               and at a price equal to [ * ] costs (determined consistently with
               [ * ], as if they were [ * ];

          (C)  if and to the extent that any Serono Production Technology in
               existence on the effective date of such termination that is
               applicable to such Licensed Product is not already covered by
               Serono's licenses to ZGI under Sections 10.2 and 10.7, the same
               shall hereby be deemed to be included in such licenses, but on a
               nonexclusive basis; and

          (D)  Serono shall promptly provide to ZGI a full disclosure of all
               Serono Production Technology, if any, that shall not have prior
               thereto been provided to ZGI to the extent the same is reasonably
               necessary to enable an experienced cGMP manufacturer to
               manufacture the applicable Licensed Product.  Serono further
               agrees to cooperate in the transfer of manufacturing operations
               for such Licensed Product to ZGI or its designated Sublicensee or
               contract manufacturer and agrees to provide all information,
               data, and copies of documents constituting Serono Production
               Technology reasonably necessary or useful for regulatory filings
               (including authorization to use such information, data and copies
               of documents in later regulatory filings) for such Licensed
               Product and to allow ZGI or such Sublicensee or contract
               manufacturer to manufacture such Licensed Product throughout the
               Product Term.

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -43-
<PAGE>

     (b)  It is further agreed, for the avoidance of doubt, that if [ * ] makes
an [ * ] as to a [ * ] which it may only do following the end of the [ * ] for
such Licensed Product [ * ] (determined under [ * ] without regard to [ * ] the
provisions of subsection (a) above will not apply; rather such [ * ] will
terminate the [ * ] Term for such Licensed Product [ * ] and the applicability
of Articles Three, Five, Six, Eight, Nine, and Eleven to such Licensed Product [
* ], and in lieu thereof, the provisions of [ * ] shall apply as to that
Licensed Product [ * ].

                                ARTICLE THIRTEEN
                 Confidentiality; Research Materials; Publicity

     13.1 Confidentiality and Non-Use.  During all Product Terms under this
          ---------------------------
Agreement, and for a period of [ * ] thereafter, each party shall maintain the
other party's Information as confidential, using the same degree of care it uses
to protect its own confidential information.  During the Term of this Agreement
and at all times thereafter, neither party shall use the other party's
Information, except for the activities contemplated by this Agreement.

     13.2 Exceptions.  The obligations of Section 13.1 shall not apply to
          ----------
Information that:

     (a)  was known by the receiving party or its Affiliates prior to disclosure
          by the disclosing party, as evidenced by prior written records;

     (b)  becomes part of the public domain through no fault of the receiving
          party or its Affiliates;

     (c)  was obtained, on a non-confidential basis, by the receiving party or
          its Affiliates from a third party having no direct or indirect
          obligation of confidentiality to the disclosing party or its
          Affiliates;

     (d)  was disclosed by the disclosing party to a third party on a non-
          confidential basis; or

     (e)  is developed by the receiving party or its Affiliates independently of
          disclosures made hereunder.

     13.3 Permitted Disclosures.  Notwithstanding Section 13.1, Serono and ZGI
          ---------------------
shall each be permitted to disclose the other party's Information:  (a) to its
Affiliates, Contractors and Sublicensees, or prospective Affiliates, Contractors
or Sublicensees, and its licensors under Third Party Agreements, who are subject
to confidentiality requirements at least as stringent as those contained herein;
(b) to its employees, and its Affiliates', Contractors' or Sublicensee's
employees who require the same for the purposes contemplated by this Agreement
and who are subject to confidentiality requirements at least as stringent as
those contained herein; (c) to its patent attorney or agent or any patent
authority in any country as shall be reasonably required for filing or
prosecuting any patent application with respect to any Patent Rights in
accordance with Article Eleven (subject to Article Twelve); (d) in support of or
in connection with any actions to defend or enforce any Patent Rights in
accordance with Article Eleven (subject to Article Twelve); (e) to Regulatory
Agencies in connection with obtaining and maintaining Regulatory

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -44-
<PAGE>

Approval and approval for the manufacture of the Licensed Product and (f) if
such disclosure is required to meet the requirements of any stock exchange or
securities laws or regulations to which either party may be subject, or by any
court or other governmental authorities of competent jurisdiction, but only
after having provided the other party written notice within a period
sufficiently prior to such disclosure to permit the other party to apply for a
protective order or take other appropriate action to restrict such disclosure
and, if disclosure is still required, so far as reasonably practicable, having
minimized the degree of such disclosure and provided such disclosure under
conditions of confidentiality.

     13.4 Research Materials; Permitted Uses.  Any Research Materials
          ----------------------------------
transferred by one party to the other pursuant to this Agreement shall be used
by the receiving party and its Contractors solely for the purposes contemplated
by this Agreement and pursuant to the Development Plan and Budget.  Any
Contractor shall be bound by terms at least as stringent as the confidentiality
and non-use obligations hereunder with respect to such Research Materials.  Any
person using Research Material on behalf of the receiving party will be advised
of, and is subject to, the terms of this Section.

     13.5 Press Releases.  The parties hereby each approve the form of joint
          --------------
press release set forth in Exhibit 13.5 hereto, and will cooperate in the
release thereof as soon as practicable after the signature of this Agreement by
the parties.  No other public announcement or other disclosure to Third Parties
(other than Sublicensees and Contractors) concerning the existence or terms of
this Agreement shall be made, either directly or indirectly, by either party
hereto, without first obtaining the written approval of the other party, which
shall include agreement upon the nature and text of such announcement or
disclosure.  The party desiring to make any such public announcement or other
disclosure shall inform the other party of the proposed announcement or
disclosure by providing the other party with a written copy thereof, and
allowing reasonably sufficient time prior to public release to permit such other
party to comment upon such announcement or disclosure.  Once any such public
announcement or disclosure has been approved in accordance with this Section,
then either party may appropriately communicate information contained in such
permitted announcement or disclosure.  Each party agrees that it shall
reasonably cooperate with the other with respect to all disclosures regarding
this Agreement to the Securities Exchange Commission and any other governmental
or regulatory agencies, including requests for confidential treatment of
proprietary information of either party included in any such disclosure.

     13.6 Publications.  Each party agrees that the parties' personnel involved
          ------------
in the Development Project, separately, together or with other authors, shall be
permitted to present at symposia, national, or regional professional meetings
and to publish in journals, theses, or dissertations, or otherwise the research
conducted pursuant to the Development Project. The foregoing permission is
subject to each party's right to receive copies of any proposed publication or
presentation in advance of the submission of such proposed publication or
presentation to a journal, editor, or other third party. Each party shall have
forty-five (45) days after receipt of said copies to object to such proposed
presentation or proposed publication either: (a) because there is subject matter
which either party desires to maintain in secrecy to maximize the commercial
value of this Agreement; or (b) because there is patentable subject matter which

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -45-
<PAGE>

needs protection. If either party makes an objection under (a) above, such
subject matter shall remain subject to Article 13 and shall not be published or
otherwise disclosed without the written consent of both parties. If either party
makes an objection under (b) above, the parties shall negotiate a mutually-
acceptable version, and both parties and such other authors (if any) shall
withhold such subject matter from such publication or presentation for a maximum
of six (6) months from the date of receipt of such objection from either party.

                                ARTICLE FOURTEEN
                         Representations and Warranties

     14.1 Representations, Warranties and Covenants of Serono.  Serono
          ---------------------------------------------------
represents and warrants to and covenants with ZGI that:

     (a)  Serono is a corporation duly organized, validly existing and in
          corporate good standing under the laws of Switzerland and has the
          corporate and legal right, title, authority and power to enter into
          and to perform this Agreement;

     (b)  This Agreement is a legal and valid obligation binding upon Serono and
          enforceable in accordance with its terms, except as enforceability may
          be limited by bankruptcy, fraudulent conveyance, insolvency,
          reorganization, moratorium and other laws relating to or affecting
          creditors' rights generally and by general equitable principles.
          Serono has taken all necessary action to authorize the execution,
          delivery and performance of this Agreement. The execution, delivery
          and performance of Serono's obligations under this Agreement will not
          conflict with or result in a breach of or a default under any
          agreements, contracts, commitments or other arrangements to which
          Serono is a party or by which it or its properties are bound or
          violate any order, law or regulation of any court, governmental
          authority or administrative or other agency having authority over it;

     (c)  Serono has in place with all of its officers and employees who will
          perform this Agreement written agreements in proper form and substance
          requiring the assignment to Serono of all inventions made during the
          course of their employment by Serono and requiring such individuals to
          maintain the confidentiality of Serono's own information and
          information that is entrusted to Serono in confidence by others;

     (d)  Serono will not during the Term of this Agreement enter into any
          agreements, contracts, commitments or other arrangements that would
          prevent Serono from meeting its obligations hereunder;

     (e)  Serono will comply and will cause its Contractors to comply with all
          applicable laws and regulations in connection with the performance of
          Serono's obligations and other activities pursuant to this Agreement,
          including all applicable product safety, product testing, product
          labeling, package marking, and product promotion and advertising laws;
          all applicable rules and regulations relating to the use of Research
          Materials, including those relating to research involving the use of

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -46-
<PAGE>

          human and animal subjects or recombinant DNA; and all laws and
          regulations of the United States and any other relevant country
          concerning any export or other transfer of technology, services or
          products;

     (f)  There are, as of the Effective Date, no Third Party Agreements to
          which Serono or any of its Affiliates are a party;

     (g)  Serono has the right, power and authority to grant the licenses
          granted by Serono herein; and

     (h)  To the best of Serono's knowledge after due inquiry, as of the
          Effective Date, Serono has not [ * ] and has no present plans [ * ]
          and it is not independently possessed of [ * ] on which it could [ * ]
          any of which [ * ] do or may [ * ] the same [ * ] in any of the [ * ]
          within the [ * ] (as described on [ * ] hereto) or that otherwise may
          be a basis for [ * ] in the [ * ] between any such [ * ] and any [ * ]
          within the ZGI Background Technology (as described on Exhibit 1.85).

     14.2 Representations, Warranties and Covenants of ZGI.  ZG1 represents and
          ------------------------------------------------
warrants to and covenants with Serono that:

     (a)  ZGI is a corporation duly organized, validly existing and in corporate
          good standing under the laws of the State of Washington and has the
          corporate and legal right, title, authority and power to enter into
          and to perform this Agreement;

     (b)  This Agreement is a legal and valid obligation binding upon ZGI and
          enforceable in accordance with its terms, except as enforceability may
          be limited by bankruptcy, fraudulent conveyance, insolvency,
          reorganization, moratorium and other laws relating to or affecting
          creditors' rights generally and by general equitable principles.  ZGI
          has taken all necessary action to authorize the execution, delivery
          and performance of this Agreement.  The execution, delivery and
          performance of ZGI's obligations under this Agreement will not
          conflict with or result in a breach of or a default under any
          agreements, contracts, commitments or other arrangements to which ZGI
          is a party or by which it or its properties are bound or violate any
          order, law or regulation of any court, governmental authority or
          administrative or other agency having authority over it;

     (c)  ZGI has in place with all of its officers and employees who will
          perform this Agreement written agreements in proper form and substance
          requiring the assignment to ZGI of all inventions made during the
          course of their employment by ZGI and requiring such individuals to
          maintain the confidentiality of ZGI's own information or information
          that is entrusted to ZGI in confidence by others;

     (d)  ZGI will not during the Term of this Agreement enter into any
          agreements, contracts, commitments or other arrangements that would
          prevent ZGI from meeting its obligations hereunder;

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -47-
<PAGE>

     (e)  ZGI will comply and will cause its Contractors to comply with all
          applicable laws, regulations in connection with the performance of
          ZGI's obligations and other activities pursuant to this Agreement,
          including all applicable product safety, product testing, product
          labeling, package marking, and product promotion and advertising laws;
          all applicable rules and regulations relating to the use of Research
          Materials, including those relating to research involving the use of
          human and animal subjects or recombinant DNA; and all laws and
          regulations of the United States and any other relevant country
          concerning any export or other transfer of technology, services or
          products;

     (f)  There are, as of the Effective Date, no Third Party Agreements to
          which ZGI or any of its Affiliates are a party, other than as listed
          in Exhibit 1.34, true and complete copies of which have been provided
          to Serono;

     (g)  ZGI has the right, power and authority to grant the licenses granted
          by ZGI herein;

     (h)  As of the Effective Date, ZGI has not [ * ] communications from any
          [ * ] that any [ * ] within the [ * ] is [ * ] or [ * ] and no [ * ]
          identified or described in this Agreement is subject to [ * ];
          provided however that nothing in this Agreement shall be construed as
          a representation or warranty as to the scope or validity of any patent
          application or patent identified or described in this Agreement;

     (i)  As of the Effective Date, ZGI has notified Serono in writing of all
          patents and patent applications, of which the ZGI intellectual
          property department is aware, that are issued to or filed by [ * ]
          that include [ * ] as an element of a claim and that may cover the
          development, manufacture, importation, sale or use of a product [ * ];

     (j)  As of the Effective Date, ZGI has notified Serono in writing of all
          patents and patent applications, of which the ZGI intellectual
          property department is aware, that are issued to or filed by [ * ]
          that may cover the use or incorporation of those materials described
          in [ * ] in connection with the development, manufacture, importation,
          sale or use of a [ * ]; and

     (k)  Novo Nordisk A/S is not an Affiliate as defined in Section 1.1.

     14.3 Research Materials.  ANY RESEARCH MATERIALS PROVIDED OR TO BE PROVIDED
          ------------------
HEREUNDER ARE EXPERIMENTAL IN NATURE AND ARE TRANSFERRED BETWEEN THE PARTIES "AS
IS" AND WITH ALL FAULTS. NEITHER SERONO NOR ZGI MAKES ANY WARRANTY OR
REPRESENTATION WITH RESPECT TO THE UTILITY, EFFICACY, NONTOXICITY, SAFETY OR
APPROPRIATENESS OF USING THE RESEARCH MATERIALS. NEITHER PARTY SHALL BE LIABLE
TO THE OTHER FOR ANY USE OF RESEARCH MATERIALS, OR ANY LOSS THAT MAY ARISE FROM
SUCH USE.

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -48-
<PAGE>

     14.4  Warranty Disclaimer.  EXCEPT AS OTHERWISE EXPRESSLY PROVIDED IN THIS
           -------------------
AGREEMENT, NEITHER PARTY MAKES ANY WARRANTY WITH RESPECT TO THE ZGI IP, SERONO
IP, JOINT PROJECT TECHNOLOGY, GOODS, SERVICES OR OTHER SUBJECT MATTER OF THIS
AGREEMENT AND HEREBY DISCLAIMS WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
PARTICULAR PURPOSE AND NON-INFRINGEMENT WITH RESPECT TO ANY AND ALL OF THE
FOREGOING.

                                ARTICLE FIFTEEN
                           Indemnification; Insurance

     15.1  Serono Indemnification.  Serono (as the "Indemnifying Party" under
           ----------------------                   ------------------
this Section) shall defend, indemnify and hold ZGI and its Affiliates,
Contractors, Sublicensees and their respective employees and agents (the
"Indemnified Parties" under this Section) harmless from and against any and all
 -------------------
claims, actions, judgments, costs, awards, expenses (including reasonable
attorneys' fees, experts' fees, and other costs of defense at any stage of
proceedings) or liability of any kind to the extent arising out of:

     (a)   Third Party claims or actions for [ * ] caused or alleged to be
           caused by [ * ] to the extent [ * ] is attributable to matters within
           the scope of [ * ] hereunder;

     (b)   Third Party claims or actions arising from [ * ] of any [ * ] or any
           activities related to [ * ] by or for [ * ];

     (c)   Third Party claims or actions arising in connection with any breach
           of any warranties, representations or covenants made by Serono or
           with its authorization hereunder; or

     (d)   [ * ] to the extent arising from or related to matters within the
           scope of Serono's responsibilities or allocated tasks hereunder or
           arising from the conduct of any Development Tasks or any activities
           related to the manufacturing, marketing, distribution, sale or
           promotion of Licensed Products by or for Serono.

provided, however, that Serono will not be required to defend, indemnify or hold
any Indemnified Party harmless from any claims, actions, judgments, costs,
awards, expenses or other liabilities to the extent resulting from:

     (i)   the negligence or willful malfeasance of any Indemnified Party;

     (ii)  any breach of ZGI's warranties, representations or covenants under
           Article Fourteen or other breach by ZGI of this Agreement; or

     (iii) any settlement or admission of liability made or purported to be
           made by any Indemnified Party without Serono's prior written
           approval.

     15.2  ZGI Indemnification.  ZGI (as the "Indemnifying Party" under this
           -------------------                ------------------
Section) shall defend, indemnify and hold Serono and its Affiliates,
Contractors, Sublicensees and their

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -49-
<PAGE>

respective employees and agents (the "Indemnified Parties" under this Section)
                                      -------------------
harmless from and against any and all claims, actions, judgments, costs, awards,
expenses (including reasonable attorneys' fees, experts' fees, and other costs
of defense at any stage of proceedings) or liability of any kind to the extent
arising out of:

     (a)   Third Party claims or actions for [ * ] damage caused or alleged to
           be caused by [ * ], to the extent [ * ] or damage is attributable to
           matters within the scope of [ * ] hereunder;

     (b)   Third Party claims or actions arising from [ * ] of any [ * ] or any
           activities related to [ * ] by or for [ * ]

     (c)   Third Party claims or actions arising in connection with any breach
           of any warranties, representations or covenants made by ZGI or with
           its authorization hereunder;

provided, however, that ZGI will not be required to defend, indemnify or hold
any Indemnified Party harmless from any claims, actions, judgments, costs,
awards, expenses or other liabilities to the extent resulting from:

     (i)   the negligence or willful malfeasance of any Indemnified Party;

     (ii)  any breach of Serono's warranties, representations or covenants under
           Article Fourteen or other breach by Serono of this Agreement; or

     (iii) any settlement or admission of liability made or purported to be
           made by any Indemnified Party without ZGI's prior written approval.

     15.3  Notice and Defense of Claims.  Serono agrees, at its own expense, to
           ----------------------------
provide attorneys to defend against any claims or actions brought or filed
against the Indemnified Parties with respect to the subject of the indemnity
contained in Section 15.1, whether or not such claims or actions are rightfully
brought or filed.  ZGI agrees, at its own expense, to provide attorneys to
defend against any claims or actions brought or filed against the Indemnified
Parties with respect to the subject of the indemnity contained in Section 15.2,
whether or not such claims or actions are rightfully brought or filed.  An
Indemnified Party seeking indemnification hereunder shall

     (a)   notify the Indemnifying Party in writing promptly after the assertion
           of any claim within the scope of the Indemnifying Party's indemnity
           agreement hereunder; provided, however, that the failure or delay so
           to notify the Indemnifying Party shall not relieve it of any
           obligation hereunder except to the extent that it demonstrates that
           such failure or delay adversely affected its ability to defend or
           resolve such claim; and

     (b)   tender to the Indemnifying Party the right to control the defense of
           any such claims or actions, including any decisions regarding the
           settlement or disposition thereof; provided, however, that

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.


                                      -50-
<PAGE>

         (i)   the Indemnifying Party shall not settle any such claim or action
               in a way that prejudices or adversely impacts an Indemnified
               Party without the prior approval of such Indemnified Party, which
               approval shall not be unreasonably withheld or delayed;

         (ii)  if the defendants in any such claims or action include both the
               Indemnifying Party and such Indemnified Party, and either of them
               concludes that there may be legal defenses available to it which
               are different from, additional to, or inconsistent with those
               available to the other party, that party shall have the right to
               select separate counsel to participate in the defense of such
               claim or action on its behalf, and such party shall bear the cost
               and expense of such separate defense, unless and to the extent
               the parties otherwise agree, or it is determined pursuant to
               Article Eighteen hereunder that such costs and expense are or
               were required to be indemnified by the Indemnifying Party
               hereunder and are or were required to be incurred separately due
               to such different, additional, or inconsistent defenses; and

         (iii) if the Indemnifying Party determines not to defend such claim
               or action, or otherwise fails to do so diligently, the
               Indemnified Party shall have the right to maintain the defense of
               such claim or action and the Indemnifying Party shall provide
               reasonable assistance to it in the defense of such claim or
               action and shall bear the reasonable cost and expense of such
               defense (including reasonable attorneys' fees, experts' fees, and
               other costs of defense at any stage of proceedings).

     Either Serono or ZGI, as applicable, shall provide, and shall cause the
Indemnified Party to provide, reasonable assistance to the Indemnifying Party in
the defense, settlement or other disposition of such claim or action, including
by making available all pertinent information and personnel under its control to
the Indemnifying Party

     15.4 Insurance.
          ---------

     (a)  From and after the Initiation of Phase I Clinical Trials for any
Licensed Product, each of ZGI and Serono shall obtain and keep in force, in form
and with insurers reasonably acceptable to the other party hereto, insurance
covering its indemnification obligations hereunder in amounts of not less than [
* ].  It is understood that such insurance shall not be construed to limit a
party's liability with respect to such indemnification obligations.

     (b)  From and after the first Regulatory Approval for a Licensed Product to
be manufactured by or on behalf of Serono hereunder and/or otherwise to be
marketed, distributed or sold by it or its Affiliates or Sublicensees, and until
three years after the end Product Term with respect thereto, Serono shall obtain
and keep in force, in form and with insurers reasonably acceptable to ZGI,
insurance covering its indemnification obligations hereunder in amounts of not
less than [ * ] provided, however, that ZGI shall, by notice to Serono from time
to time during such Product Term, but not more often than bi-annually, have the
right reasonably to

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -51-
<PAGE>

increase the foregoing coverage amounts such that they remain commensurate with
the insurance coverage levels generally maintained by entities manufacturing or
marketing products for human use in the pharmaceutical industry. It is
understood that such insurance shall not be construed to limit a party's
liability with respect to such indemnification obligations.

     (c)  From and after the first Regulatory Approval for a Licensed Product to
be manufactured by or on behalf of ZGI hereunder and/or otherwise to be
marketed, distributed or sold by it or its Affiliates or Sublicensees, and until
three years after the end Product Term with respect thereto, ZGI shall obtain
and keep in force, in form and with insurers reasonably acceptable to Serono,
insurance covering its indemnification obligations hereunder in amounts of not
less than [ * ] provided, however, that Serono shall, by notice to ZGI from time
to time during such Product Term, but not more often than bi-annually, have the
right reasonably to increase the foregoing coverage amounts such that they
remain commensurate with the insurance coverage levels generally maintained by
entities manufacturing or marketing products for human use in the pharmaceutical
industry.  It is understood that such insurance shall not be construed to limit
a party's liability with respect to such indemnification obligations.

     (d)  Each party shall provide to the other party upon request a certificate
evidencing the insurance such party is required to obtain and keep in force
under this Article.  Such certificate shall provide that such insurance shall
not expire or be cancelled or modified without at least thirty (30) days' prior
notice to the other party.

                                ARTICLE SIXTEEN
                               Change of Control

     16.1 Loss of Co-Promotion Right for a Licensed Product.  Serono shall
          -------------------------------------------------
have the right to terminate ZGI's right to co-promote a Licensed Product
pursuant to Article Five if:

     (a)  There has been [ * ] of [ * ] (as defined below) and not [ * ] of
[ * ] (as defined below);

     (b)  The Acquiring Company (as defined below) of ZGI [ * ] for a product
for which the [ * ] are substantially similar to those set forth in a [ * ]
under this Agreement for the [ * ] and

     (c)  Serono elects to terminate such co-promotion right within [ * ] after
the later of (i) the effective date of [ * ] and (ii) the last to be filed of
such [ * ] for the [ * ] and such [ * ] for the [ * ].  Such election of Serono
pursuant to this Section 16.1 shall be deemed to be [ * ] made by [ * ].

     For purposes hereof, "Change of Control of ZGI" means that ZGI has been
                           ------------------------
acquired by a [ * ] (the "Acquiring Company") that has immediately after the
                          -----------------
acquisition together with its Affiliates and ZGI [ * ] Affiliates on a worldwide
basis; [ * ] in North America [ * ] most recently ended; or [ * ].

     For purposes hereof, [ * ] means any acquisition, reorganization, merger or
consolidation of Serono or its direct or indirect parent corporation with or
into another corporation (a "Control
                             -------

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -52-
<PAGE>

Event"), other than a Control Event in which [ * ] or its successors, either
-----
directly or indirectly, (A) will have [ * ] of the ownership of voting capital
stock of the acquiring or surviving corporation in such Control Event
immediately after the Control Event, (B) will be [ * ] stock of such acquiring
or surviving corporation immediately after the Control Event, [ * ] (C) will be
able to [ * ] of such acquiring or surviving corporation immediately after the
Control Event.

     16.2 Decisions Regarding Commercialization Budget.  In the event there is a
          --------------------------------------------
Change of Control of [ * ] and so long as there has not been a Change of Control
of [ * ] shall be entitled to break any deadlocks [ * ] regarding [ * ].

                               ARTICLE SEVENTEEN
                              Term and Termination

     17.1 Term.  This Agreement shall become effective as of the Effective
          ----
Date and shall continue in full force and effect until the later of (i) the
expiration of the Development Project Term or (ii) the expiration of the last
Product Term for any Licensed Product hereunder (such period hereinafter the
"Term").  Upon expiration of the Product Term of a Licensed Product in
Commercial Use in a country, all rights licensed hereunder as to such Licensed
Product and country shall become irrevocable and fully-paid upon payment of any
amounts due that have accrued hereunder prior to expiration, and thereafter
Serono shall have exclusive rights to all Licensed Product Trademarks and
Regulatory Approvals and, except in such countries where restricted by
applicable law, shall have an exclusive license, with the right to sublicense,
to ZGI IP, Ig Fusion Technology and ZGI's interest in Joint Project Technology
to make, have made, use, sell, offer to sell, and import such Licensed Product
in such country.

     17.2 Termination for Material Breach.  Serono and ZGI shall have the right
          -------------------------------
to terminate this Agreement, including the licenses granted herein, in the event
that any material term or condition of this Agreement is breached by the other
party, and such breach is not remedied within a period of [ * ] days after the
other party's receipt of written notice of such breach; provided, however, that
if the party claimed to be in breach disputes in good faith that the claimed
breach exists, such [ * ]-day period will not start to run until such dispute
has been resolved, provided that:

     (a)  the party claimed to be in breach shall, within [ * ] days after the
          notice to it of breach under this Section, remedy any breach to the
          extent its existence is not the subject of such good faith dispute;
          and

     (b)  either of the parties has, within [ * ] days after the notice of
          breach under this Section, initiated the escalation procedures of
          Article Eighteen in order to resolve such good faith dispute.

If such material breach is corrected within the [ * ]-day period, this Agreement
and the rights granted hereunder shall continue in full force and effect.

     17.3 Termination Upon Serono's Bankruptcy.  This Agreement will
          ------------------------------------
automatically terminate if Serono becomes insolvent, makes an assignment for the
benefit of its creditors,


[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -53-
<PAGE>

appoints or suffers appointment of a receiver or trustee over its property,
files a petition under any bankruptcy or insolvency act or has such a petition
filed against it and any such event shall have continued for [ * ] days
undismissed or undischarged.

     17.4 No Termination Upon ZGI's Bankruptcy.  All rights and licenses
          ------------------------------------
granted under or pursuant to this Agreement by ZGI to Serono are, and shall
otherwise be deemed to be, for purposes of Section 365(n) of the United States
Bankruptcy Code, as amended from time to time (the "Bankruptcy Code"), licenses
of rights to "intellectual property" as defined under Section 101(35A) of the
Bankruptcy Code.  The parties agree that Serono, as a licensee of such rights
under this Agreement, shall retain and may fully exercise all of its rights and
elections under the Bankruptcy Code.  The parties further agree that, in the
event of the commencement of a bankruptcy proceeding by or against ZGI under the
Bankruptcy Code that is not dismissed within sixty (60) days after it is filed,
Serono shall be entitled to a complete duplicate of (or complete access to, as
appropriate) any such intellectual property and all embodiments of such
intellectual property, and the same, if not already in its possession, shall be
promptly delivered to Serono (i) upon any such commencement of a bankruptcy
proceeding upon written request therefor by Serono, unless ZGI elects to
continue to perform all of its obligations under this Agreement, or (ii) if not
delivered under (i) above, upon the rejection of this Agreement by or on behalf
of ZGI, upon written request therefor by Serono.  Following the commencement of
such a bankruptcy proceeding and so long as such proceeding continues, ZGI will
not, without Serono's prior written consent, sell, transfer, assign or otherwise
dispose of, or purport to sell, transfer, assign or otherwise dispose of, any
right, title or interest in, to or under the ZGI IP or the Joint Project
Technology that has been licensed to Serono under this Agreement.

     17.5 Termination of License With Respect to Contested Patent Rights.
          --------------------------------------------------------------
Either ZGI [ * ] under this Agreement, or Serono [ * ] under this Agreement, may
at its option terminate [ * ] to the other party under this Agreement to the
extent covering [ * ] as to which the other party hereto commences any action or
asserts any formal position in any forum (including a court, a patent office, or
an arbital tribunal, and whether in the form of petitions for declaratory
relief, claims, counterclaims, defenses, interferences, petitions for re-
examination, oppositions, or otherwise) [ * ].

     17.6 Accrued Rights and Surviving Provisions.    Expiration or termination
          ---------------------------------------
of this Agreement shall not affect the parties' rights and obligations that have
accrued as of the expiration or termination date, including the parties'
obligations to bear Development Costs or North American Commercialization Costs
incurred prior to the effectiveness of the expiration or termination and their
obligations with respect to royalties or Milestone Fees hereunder that have
accrued prior to the effectiveness of the expiration or termination.  Upon any
termination of this Agreement, Serono shall have the right to sell its inventory
of Licensed Products for a period of six (6) months from the date of
termination, provided Serono complies with the provisions of Articles Eight,
Nine and Twelve hereof.  The parties' rights and obligations under Sections 4.6
and 5.5 and those provisions of Articles Nine, Twelve, Thirteen, Fifteen, and
Seventeen through Nineteen that by their context are intended to survive, shall
so survive.  Any right to terminate this Agreement shall be in addition to and
not in lieu of all other rights or remedies that the party

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -54-
<PAGE>

giving notice of termination may have at law, in equity or otherwise, including
rights under the United States Bankruptcy Code.

                                ARTICLE EIGHTEEN
                               Dispute Resolution

     18.1 Cooperative Decision Making; Senior Executives. The parties intend
          ----------------------------------------------
that, to the maximum extent practicable, they shall reach decisions hereunder
cooperatively through the deliberations of the Steering Committee and by consent
of its members as described in subsection 1.74(a). In situations in which that
does not occur, [ * ] may as described in subsection 1.74(b) institute the
procedure described in this Article. In such circumstances, a summary of the
proposed Steering Committee Action and the unresolved dispute will be provided
in writing to [ * ]. If either party has not then [ * ], such summary shall be
provided to [ * ] with a request that one or more [ * ]. [ * ] and forward the
summary to them. The [ * ] the proposed Steering Committee Action, and [ * ] if
one or more of them believes a meeting or meetings to be useful. If the [ * ] do
not resolve the matter by either approving in writing the proposed [ * ]
(whether or not in a revised form) or agreeing in writing to reject it, within [
* ] following the receipt by them (or by the [ * ] for either or both of them,
as described above) of the summary of the proposed action and the unresolved
dispute (or such lesser or longer period as they may agree is a useful period
for their discussions), then any one or more of the [ * ] may institute a formal
review of such matter by the [ * ] pursuant to [ * ].

     18.2 Review by CEOs.  Any dispute or difference between the parties arising
          --------------
out of or in connection with this Agreement, including a disagreement over a
proposed Steering Committee Action, that cannot be resolved pursuant to Section
18.1 shall be referred for review by the [ * ]. In the event of a dispute or
difference over proposed Steering Committee Action, a summary or summaries of
the proposed Steering Committee Action and the unresolved dispute will be
provided in writing by the [ * ] to the parties' [ * ] . Such [ * ] shall
discuss the proposed dispute or difference, and shall meet with respect thereto
if either of them believes a meeting or meetings to be useful. If the [ * ] do
not resolve the dispute or difference within [ * ] (or such lesser or longer
period as they may agree is a useful period for their discussions), and in the
case of a dispute or difference involving Steering Committee Action, such
resolution to be in accordance with the terms and conditions stated in [ * ]
then (except as provided in [ * ] may submit the dispute or difference to be
resolved by [ * ] pursuant to [ * ].

     18.3 Arbitration.  Should the parties fail to reach agreement with respect
          -----------
to a dispute or difference (other than as to a dispute relating to patent
validity or as to a matter left to the discretion of a party hereunder), between
the parties arising out of or in connection with this Agreement, including
without limitation a disagreement over a proposed Steering Committee Action,
then the dispute or difference will be determined [ * ] in accordance with [ * ]
by a [ * ] of [ * ] and [ * ] one of which will be [ * ], and the [ * ] of which
shall have had both training and experience as a [ * ].  If the parties to this
Agreement cannot agree [ * ] then [ * ] will be [ * ] by [ * ] in accordance
with the criteria set forth in the preceding sentence. The [ * ] may decide any
[ * ] as to whether, or as to the extent to which, any [ * ] and other [ * ]
provisions in this Agreement.  Any [ * ] by the [ * ] must be consistent with
the provisions of this Section 18.3 and

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -55-
<PAGE>

the [ * ] must [ * ] award in a writing, which writing must include [ * ] of the
[ * ] for such [ * ]. Any [ * ] pursuant to this section will be governed by [ *
] applicable to [ * ] made and to be [ * ] without regard to [ * ] and by the [
* ] and [ * ] upon the [ * ] rendered by the [ * ] may be entered by [ * ]
having [ * ] thereof. The [ * ] of the [ * ] applicable to the [ * ] will apply
to the [ * ] of an [ * ] under this section, except that no [ * ] will be
available based upon [ * ] during any [ * ] or [ * ] required pursuant to this
Article 18. All [ * ] of the [ * ] and all other costs and expenses of the [ * ]
will be [ * ] by the parties to this Agreement unless such parties [ * ] or
unless [ * ] assesses such [ * ] against [ * ] or [ * ] other than [ * ].
Pending the [ * ] of the [ * ] the parties shall [ * ] obligations under this
Agreement. Notwithstanding the foregoing, [ * ] on good cause shown [ * ] and/or
a [ * ] from a [ * ] to be effective pending [ * ] of the [ * ] or the [ * ] of
the [ * ].

     18.4 Matters to Proceed to Court.  Notwithstanding the foregoing, any [ * ]
          ----------------------------
relating to the [ * ] of a party's [ * ] or other issues relating solely to a
party's [ * ] and any [ * ] of this Agreement, including [ * ] made hereunder
shall be submitted [ * ] to the [ * ] and the parties hereby [ * ] to the [ * ]
of such [ * ].

                                ARTICLE NINETEEN
                                    General

     19.1 Entire Agreement.  This Agreement, together with all of the Exhibits
          ----------------
hereto, constitutes the entire agreement between the parties and supersedes all
prior and contemporaneous oral and written agreements, understandings or
arrangements relating to the subject matter hereof.  This Agreement has been
submitted to the scrutiny of, and has been negotiated by, both parties and their
counsel, and shall be given a fair and reasonable interpretation in accordance
with its terms, without consideration or weight being given to any such term's
having been drafted by any party or its counsel.

     19.2 Controlling Law.  This Agreement shall be governed by and construed
          ---------------
in accordance with the laws of the State of New York, without giving effect to
the doctrine of conflict of laws, except that the issues of patentability,
validity, enforceability and scope of any Patent Rights shall be determined
according to the patent laws of the Patent Country of such Patent Rights.

     19.3 Notices.  All notices, reports and other communications by ZGI or
          -------
Serono to the other shall:  (a) be in writing; (b) refer specifically to this
Agreement; and (c) be sent by electronic or facsimile transmission for which a
confirmation of delivery is obtained or by express courier services providing
evidence of delivery, in each case to the respective address specified below (or
to such updated address as may be specified in writing to the other party from
time to time).

     If to Serono:

          Ares Trading S.A.
          Chateau de Vaumarcus
          2028 Vaumarcus

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -56-
<PAGE>

          Switzerland
          Attn: General Manager
          FAX:  41-32-836-3899

     with a copy to:

          Serono S.A.
          c/o Serono International S.A.
          15 bis, Chemin des Mines
          Case Postale 54
          CH-1211 Geneve 20
          Switzerland
          Attn: General Counsel
          FAX:  41-22-739-3070

     If to ZGI:

          ZymoGenetics, Inc.
          1201 Eastlake Avenue East
          Seattle, WA 98102
          U.S.A.
          Attn: Senior Director, Intellectual Property
          FAX:  (206) 442-6697

     Such notice, report or other communication will be deemed effective as of
the date so delivered either by courier service or by electronic or facsimile
transmission.

     19.4 Force Majeure.   If either party hereto is prevented from carrying
          -------------
out its obligations under this Agreement by events beyond its reasonable
control, including acts or omissions of the other party, acts of God or
government, natural disasters or storms, fire, political strife, labor disputes,
failure or delay of transportation, default by suppliers or unavailability of
raw materials, then such party's performance of its obligations hereunder shall
be excused during the period of such events and for a reasonable period of
recovery thereafter, and the time for performance of such obligations shall be
automatically extended for a period of time equal to the duration of such
events; provided, however, that the party claiming force majeure shall promptly
notify the other party of the existence of such force majeure, shall use
commercially reasonable efforts to avoid or remedy such force majeure and shall
continue performance hereunder with the utmost dispatch whenever such force
majeure is avoided or remedied.

     19.5 Subcontracting.  Neither party may delegate or subcontract any of
          --------------
its obligations hereunder except to a Contractor in accordance with Section
1.15.

     19.6 Assignability.   Except an assignment that does not relieve the
          -------------
assigning party of any of its responsibilities or obligations hereunder and in
which the acquiring party agrees to be bound by all obligations of the
transferring party under this Agreement, and that is made in connection with the
transfer of all or substantially all of the assets of a party and its Affiliates

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -57-
<PAGE>

related to their respective pharmaceutical businesses to a single buyer or
pursuant to a merger or other corporate reorganization, neither this Agreement
nor any right herein granted may be assigned by either party to any Affiliate or
Third Party, without the prior, express written consent of the other party,
which consent shall not be unreasonably withheld.  Notwithstanding the forgoing,
Serono may assign its rights and interests under this Agreement to an entity
that was an Affiliate of Serono as of the Effective Date and that is also an
Affiliate of Serono as of the date of such assignment; provided that such
assignment [ * ] (except in the case of an assignment to [ * ] as contemplated
by [ * ] of any of its responsibilities or obligations hereunder and (including
in the case of an assignment to [ * ] as contemplated by [ * ] the assignee
agrees to be bound by all obligations of [ * ] hereunder, including, without
limitation, the obligations set forth in [ * ].  Any purported assignment
prohibited hereunder and made without [ * ] shall be void and shall constitute a
material breach of this Agreement.  A sale or transfer of the ownership or
control of [ * ] to whom it has assigned its rights or interest under this
Agreement as provided herein other than in connection with the transfer of all
or substantially all of the assets of [ * ] related to their respective [ * ]
shall be deemed to be a prohibited assignment by [ * ].  If, as a result of any
assignment of any rights or interest in this Agreement by [ * ] any payment by
or on behalf of [ * ] is subject to an increased level of withholding than would
have been the case otherwise under this Agreement and [ * ] cannot use any [ * ]
to offset against its obligation to pay [ * ] in the year in which the
withholding is effected, [ * ] an amount such that after [ * ] of any amount [ *
] receives the same amount that it would have received but for the assignment;
provided that if [ * ] in a [ * ] shall reimburse [ * ] for the amount paid to [
* ] as a result of the [ * ] giving rise [ * ].

     19.7 Amendments and Waivers.   No terms or provisions of this Agreement
          ----------------------
shall be varied or modified by any prior or subsequent statement, conduct or act
of either of the parties, whether oral or written, except that the parties may
amend this Agreement by written instruments specifically referring to, and
executed in the same manner as, this Agreement.  No waiver of any right or
remedy hereunder shall be effective unless in a writing signed by the party to
be bound, nor shall any wavier in one instance constitute a waiver of the same
or any other right or remedy in any other instance.

     19.8 Severability.   If any provision hereof should be held invalid,
          ------------
illegal or unenforceable in any respect in any jurisdiction, then, to the
fullest extent permitted by law:  (a) all other provisions hereof shall remain
in full force and effect in such jurisdiction and shall be liberally construed
in order to carry out the intentions of the parties hereto as nearly as is
possible; and (b) such invalidity, illegality or unenforceability shall not
affect the validity, legality or enforceability of such provision in any other
jurisdiction.  To the extent permitted by applicable law, ZGI and Serono hereby
waive their right to enforce any provision of law that would render any
provision hereof prohibited or unenforceable in any respect.  If the terms and
conditions of this Agreement are materially altered as a result of this Section
19.8, the parties shall attempt to renegotiate the terms and conditions of this
Agreement, in good faith, to resolve any inequities.

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -58-
<PAGE>

     19.9   Counterparts.   This Agreement may be executed in counterparts, each
            ------------
of which shall be deemed an original, and all of such counterparts taken
together shall constitute one and the same instrument.

     19.10  Relationship.  This Agreement shall not create any employer-employee
            ------------
relationship between ZGI and Serono, nor shall it be deemed to establish a joint
venture or partnership between ZGI and Serono. Neither party shall at any time
enter into or incur, or hold itself out to third parties as having the authority
to enter into or incur, on behalf of the other party, any commitment, expense or
liability whatsoever. Nothing contained in this Agreement shall be construed, by
implication or otherwise, as an obligation incurred by either party to enter
into any further agreement with the other party.

     19.11  Use of Names, Trade Names and Trademarks.    Except as provided
            ----------------------------------------
herein, nothing contained in this Agreement shall be construed as conferring any
right on either party to use in advertising, publicity or other promotional
activities any name, trade name, trademark or other designation of the other
party hereto or of any of its licensors under any Third Party Agreement,
including any contraction, abbreviation or simulation of any of the foregoing,
unless the express written permission of such other party has been obtained.

     19.12  Headings.    The article and section headings contained herein are
            --------
for reference only and shall not be considered a part of this Agreement, nor
shall they in any way affect the interpretation hereof.

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

                              Ares Trading S.A.



                              By:  /s/ Ernesto Bertarelli
                                   ----------------------------
                                   Ernesto Bertarelli
                              Its: Authorized Representative



                              ZymoGenetics, Inc.



                              By:  /s/ Bruce L.A. Carter
                                   ---------------------
                                   Bruce L.A. Carter, Ph.D.
                              Its: President and Chief Executive Officer

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -59-
<PAGE>

                                  EXHIBIT 1.20
to the Collaborative Development and Marketing Agreement, dated August 30, 2001,
                by and between ZGI and Serono (the "Agreement")

                        DEVELOPMENT COSTS AND PRINCIPLES

1    Definitions.

     Words and phrases used in this Exhibit shall have the meanings defined
elsewhere in the Agreement.  In addition, the following words and phrases shall
have the following stated or referenced meanings in this Exhibit:

     [ * ] - [3 PAGES OMITTED]


[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -1-
<PAGE>

                                 EXHIBIT 1.34
to the Collaborative Development and Marketing Agreement, dated August 30, 2001,
                by and between ZGI and Serono (the "Agreement")

                        EXISTING THIRD PARTY AGREEMENTS

                                     [ * ]

     [ * ]

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -1-
<PAGE>

                                 EXHIBIT 1.36
to the Collaborative Development and Marketing Agreement, dated August 30, 2001,
                by and between ZGI and Serono (the "Agreement")

                             IG FUSION TECHNOLOGY



     [ * ] - [4 PAGES OMITTED]

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -1-
<PAGE>

                                 EXHIBIT 1.46
to the Collaborative Development and Marketing Agreement, dated August 30, 2001,
                by and between ZGI and Serono (the "Agreement")

             NORTH AMERICAN COMMERCIALIZATION COSTS AND PRINCIPLES

     [ * ]

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -1-
<PAGE>

                                 EXHIBIT 1.70
to the Collaborative Development and Marketing Agreement, dated August 30, 2001,
                by and between ZGI and Serono (the "Agreement")

                         SERONO BACKGROUND TECHNOLOGY



     [ * ]

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -1-
<PAGE>

                                 EXHIBIT 1.85
to the Collaborative Development and Marketing Agreement, dated August 30, 2001,
                by and between ZGI and Serono (the "Agreement")

                           ZGI BACKGROUND TECHNOLOGY

                                     [ * ]

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -1-
<PAGE>

                                 EXHIBIT 13.5
to the Collaborative Development and Marketing Agreement, dated August 30, 2001,
                by and between ZGI and Serono (the "Agreement")

                          INITIAL JOINT PRESS RELEASE


Contact:
Charles Hart                                    Name
Sr. Director, Corporate Communication &         Title
Investor Relations                              Serono S.A.
ZymoGenetics, Inc.                              Phone
(206) 442-6600                                  www.serono.ch
www.zymogenetics.com                            -------------
--------------------

Sharon Karlsberg
Director
Feinstein Kean Healthcare
(617) 577-8110
www.fkhealth.com
----------------

DRAFT - NOT FOR PUBLIC RELEASE

                ZymoGenetics and Serono Establish Collaboration
             for Co-Development of Products for Autoimmune Disease

Seattle, WA and Geneva, Switzerland, [Month XX], 2001 -

ZymoGenetics and Serono S.A. (SWX Swiss Exchange: SEO and NYSE: SRA) announced
that they have entered into an exclusive co-development and commercialization
agreement focused on two preclinical product candidates derived from
ZymoGenetics' discovery research.  Using a genomics-driven approach,
ZymoGenetics' scientists identified the two molecules, termed TACI and BCMA, as
key regulators of the human immune system. These two proteins are cell-surface
receptors found on B-lymphocytes, cells involved in the production of
antibodies.

The companies intend to focus their activities on the development of one or more
products based on these receptors for the treatment of autoimmune diseases where
there is an over production of autoantibodies (antibodies that attack ones own
cells).  Serono has extensive experience in the research and treatment of
autoimmune diseases such as multiple sclerosis and rheumatoid arthritis, where
there remains significant unmet medical needs.

"This exciting collaboration with Serono underscores the power of ZymoGenetics'
product discovery engine," stated Bruce L.A. Carter, Ph.D., President and Chief
Executive Officer of ZymoGenetics.  "In addition to working with a world leader
in the development of protein

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request for confidential treatment filed separately with the Commission.

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therapeutics we will also benefit from Serono's long-standing expertise as we
build our own clinical development and manufacturing capabilities here at
ZymoGenetics."

"This collaboration exemplifies Serono's approach to access novel genomics-based
technologies through strategic partnerships and emphasizes our commitment to the
treatment of autoimmune and serious inflammatory diseases," commented Silvano
Fumero, Head of Research and Pharmaceutical Development at Serono.
"ZymoGenetics' expertise in functional genomics combined with our own experience
in product development and commercialization will help take these preclinical
product candidates through development."

Under the terms of the agreement, ZymoGenetics could receive license fees and
milestone payments of up to $52.5 million linked to the development and approval
of products, and will receive undisclosed royalties on product sales.  The two
companies will share research and development expenses worldwide, excluding
Japan where Serono will cover all expenses.  ZymoGenetics retains an option to
co-promote products with Serono in North America.  If ZymoGenetics exercises
this option the two companies will share commercialization expenses and profits
equally.  Serono will have exclusive rights to market products in the remainder
of the world.  Serono will manufacture all products for both clinical trials and
commercial sale.

"A key component of this agreement is ZymoGenetics' participation in the sales
and marketing of products resulting from the collaboration," Dr. Carter added.
"We see this as critical to the long-term development of our business.  Our
ultimate goal is to be a fully integrated company that spans from initial drug
discovery to the sale of biopharmaceutical products.  By partnering with Serono,
we believe that we have enhanced our efforts toward this goal."

For further information please contact:

  Serono International S.A., Geneva, Switzerland:
  Media Relations:           Investor Relations:          Noonan/Russo
                                                          Communications:
  Tel:  +41-22-739 36 00     Tel:  +41-22-739 3601        Tel:  +44-20 7726 4452
  Fax:  +41-22-739 30 85     Fax:  +41-22-739 3022        Fax:  +44-20 7726 4453
  www.serono.com             Reuters: SEOZ.VX             www.noonanrusso.com
  --------------             Bloomberg: SEO VX            -------------------
                              EQUITY / SRA US


  Serono, Inc., Norwell, MA
  Media Relations:
  Tel.   +1 781 681 2340
  Fax:  +1 781 982 1369
  www.seronousa.com
  -----------------


About ZymoGenetics

ZymoGenetics is an independent biopharmaceutical company focused on the
discovery and development of protein therapeutics for the prevention or
treatment of significant human

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request for confidential treatment filed separately with the Commission.

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<PAGE>

diseases. Using its proven product discovery engine, comprising genomics,
bioinformatics, protein chemistry and preclinical biology, ZymoGenetics has
generated a broad pipeline of proprietary product candidates. ZymoGenetics will
commercialize these products through internal development, collaborations with
biopharmaceutical partners, and out-licensing of its extensive patent portfolio.
For further information, visit www.zymogenetics.com.
                               --------------------

About Serono

Serono is a global biotechnology leader. The Company has six recombinant
products on the market, Gonal-F(R), Luveris(R), Ovidrel(R), Rebif(R),
Serostim(R) and Saizen(R), (Rebif(R) and Luveris(R) are not approved in the
USA). In addition to being the world leader in reproductive health, Serono has
strong market positions in neurology, metabolism and growth. The Company's
research programs are focused on growing these businesses and on establishing
new therapeutic areas. Currently, there are thirteen molecules in development.

In 2000, Serono achieved worldwide revenues of US$1.240 billion, and a net
income of US$301 million, making it the third largest biotech company in the
world based on revenues. The Company operates in 45 countries, and its products
are sold in over 100 countries. Bearer shares of Serono S.A., the holding
company, are traded on the SWX Swiss Exchange (SEO) and its American Depositary
Shares are traded on the New York Stock Exchange (SRA).

Some of the statements in this press release are forward looking. Such
statements are inherently subject to known and unknown risks, uncertainties and
other factors that may cause actual results, performance or achievements of
Serono S.A. and affiliates to be materially different from those expected or
anticipated in the forward-looking statements. Forward-looking statements are
based on Serono's current expectations and assumptions, which may be affected by
a number of factors, including those discussed in this press release and more
fully described in Serono's Annual Report on Form 20-F filed with the U.S.
Securities and Exchange Commission on April 23, 2001. These factors include any
failure or delay in Serono's ability to develop new products, any failure to
receive anticipated regulatory approvals, any problems in commercializing
current products as a result of competition or other factors, our ability to
obtain reimbursement coverage for our products, and government regulations
limiting our ability to sell our products. Serono has no responsibility to
update the forward-looking statements contained in this press release to reflect
events or circumstances occurring after the date of this press release.

                                      ###

BACKGROUND INFORMATION

Autoimmune Disease Progression
------------------------------
One of the key components of the autoimmune disease process is the development
of antibodies to an individual's own healthy tissues.  When normal immune
function goes awry due to altered development, inherited disorders or
environmental factors, the body's B cells (B lymphocytes) produce
"autoantibodies." These autoantibodies then attack the individual, leading to
destruction of specific tissues.  Depending upon the type of autoimmune
disorder, targeted tissues may be the kidney, as in systemic lupus erythematosus
(SLE); the muscle system, as in myasthenia gravis and multiple sclerosis; or
portions of the joint, as in rheumatoid arthritis.  Currently available
treatments for these conditions are often limited due to toxic side effects,
including their overall suppressive effects on the human immune system.  New
therapies that act specifically on destructive B cell pathways provide a novel
opportunity to improve patient outcomes.

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request for confidential treatment filed separately with the Commission.

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TACI and BCMA Product Candidates
--------------------------------
The two product candidates, TACI and BCMA, are receptors found on B cells, that
when stimulated, induce the production of antibodies.  In the case of autoimmune
disease these are autoantibodies (antibodies that attack one's own cells). Using
their bioinformatics gene discovery platform, scientists at ZymoGenetics
initially identified a growth factor called BlyS (also known as BAFF, TALL-1,
THANK and zTNF4) that is a key mediator in regulating the human immune system.
This factor was found to bind to B cells, stimulating the replication and
survival of these cells, and inducing their production of antibodies. Using
their expertise in pairing growth factors with their corresponding receptors,
the ZymoGenetics scientists subsequently identified two receptors, TACI and
BCMA, that are found on the surface of B cells and that bind BLyS.  These
receptors also bind a second growth factor called APRIL.  The importance of this
pathway for regulating B cell function is demonstrated in a recent publication
from ZymoGenetics (Immunity, 15;289-302,2001) where the gene for BLyS was
eliminated in mice, thereby preventing the production of BLyS protein.  These
mice had virtually no mature B cells present and had reduced serum antibody
response to immunization. ZymoGenetics scientists further showed that mice
genetically engineered to over express the gene for BlyS develop symptoms of the
autoimmune disease systemic lupus erythematosus (SLE), including the generation
of autoantibodies (Nature 404;995-999, 2000).  Reports from ZymoGenetics and
others have also demonstrated an association between elevated levels of
circulating BLyS and autoimmune disease, including SLE in mice and humans and
rheumatoid arthritis in humans.

By using the receptor portions of TACI and BCMA responsible for binding the
growth factors, ZymoGenetics researchers have produced antagonist proteins that
can "mop up" increased BLyS and APRIL growth factor present in the blood.  Such
a soluble TACI- or BCMA- molecule thus prevents binding of the growth factors to
the B cells, regulating the development of mature B cells and antibody
production.  In published studies (Immunity, 2001), scientists at ZymoGenetics
demonstrated that in TACI transgenic mice, mice that have been genetically
engineered to over express a soluble form of the TACI receptor, there are fewer
mature B cells and reduced levels of circulating antibody.  Similar results were
observed in normal mice treated with soluble TACI receptor.

Through the ability of soluble receptors to bind to and eliminate the BLyS and
APRIL growth factors and consequently avert production of destructive
autoantibodies, it may be possible to limit the extent of tissue damage observed
in patients with autoimmune disease.  In animal models of SLE, for example,
scientists at ZymoGenetics demonstrated that a soluble form of TACI-receptor was
effective in limiting progression of the disease (Nature, 2000). Similarly, in a
mouse model of collagen-induced arthritis, ZymoGenetics scientists demonstrated
that treatment with soluble TACI-receptor was able to inhibit the development of
collagen-specific antibodies and the incidence of disease (Immunity, 2001).

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -4-
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                                EXHIBIT 14.2(j)
to the Collaborative Development and Marketing Agreement, dated August 30, 2001,
                by and between ZGI and Serono (the "Agreement")

                 MATERIALS TO BE TRANSFERRED BY ZGI TO SERONO

     [ * ]

[ * ] designates portions of this document that have been omitted pursuant to a
request for confidential treatment filed separately with the Commission.

                                      -1-