EXHIBIT 10.2
                             CONFIDENTIAL TREATMENT



                     DEVELOPMENT AND MANUFACTURING AGREEMENT

This  development and  manufacturing  agreement is made and entered into on this
12th day of July 2000.

 BY                                AND BETWEEN:  CYTOGEN CORPORATION,  a company
                                   incorporated under New Jersey law, having its
                                   registered  address at 600 College Road East,
                                   Princeton,  New  Jersey  08540-5308,   United
                                   States of America (hereinafter referred to as
                                   "CYTOGEN"), of the one part;
 AND:                              DSM BIOLOGICS COMPANY B.V., a company
                                   incorporated under Dutch law,  having its
                                   registered  address at 72/2 Zuiderweg,
                                   9744 Groningen, The Netherlands (hereinafter
                                   referred to as "DSM Biologics"), of the other
                                   part;

CYTOGEN and DSM  Biologics  hereinafter  sometimes  individually  referred to as
"Party" and collectively as "Parties".

SECTION 1 - PREAMBLE
--------------------

WHEREAS,  CYTOGEN  avails of a hybridoma  cell line for expressing a protein for
inclusion in a product known by CYTOGEN as  Prostascint(R)  and wishes to have a
manufacturing  process developed for this cell line and have manufactured  three
(3) cGMP batches of this protein  which will  thereafter  be  conjugated  by DSM
Biologics;

WHEREAS, DSM Biologics has expertise and know-how in the area of development and
production of biopharmaceutical products;

WHEREAS,  the Parties have signed a letter of commitment  dated January 26, 2000
for the  commencement  by DSM Biologics of some  development  activities for the
CYTOGEN hybridoma cell line;

NOW,  THEREFORE,  IN CONSIDERATION OF THE MUTUAL COVENANTS AND AGREEMENTS HEREIN
CONTAINED, IT IS HEREBY AGREED BY THE PARTIES HERETO AS FOLLOWS:

SECTION 2 - DEFINlTIONS
-----------------------

In this Agreement the following  terms,  whether used in the singular or plural,
shall, as used herein, have the following respective meanings:



<PAGE>
 2.1     "Acceptance" has the meaning ascribed thereto in Section 5.3;

 2.2     "Affiliates"  means  any  individual,  company,  partnership  or other
         entity  which  directly  or  indirectly,  at present or in the future,
         controls, is controlled by or is under common control with a Party;

 2.3     "Agreement" means this development and manufacturing agreement;

 2.4     "Batch  Records" means for each batch of Product  manufactured in Step
         5, the production protocols showing how the batch was manufactured;

 2.5     "Bill of Testing"  means a document  carrying  Product  and/or Project
         identification,  and stating  for the  Process the list of  analytical
         tests,  their standard methods and procedures,  and the criteria to be
         met during the cGMP manufacturing Product, and all amendments thereto,
         to be agreed upon between the Parties;

 2.6     "CCN" means a so-called  contemplated change  notification  describing
         any material  deviation from the Project,  which notice is provided in
         writing by DSM Biologics to CYTOGEN and must be approved by CYTOGEN in
         writing prior to taking effect;

 2.7     "cGMP"  means  current  good   manufacturing   practices  and  general
         biological  products  standards as promulgated under the United States
         Federal  Food,  Drug  and  Cosmetic  Act  at  21  CFR,  Canadian  Good
         Manufacturing  Practices  and the  EEC  Guide  to  Good  Manufacturing
         Practices  for  Medical  Products  (Vol.  IV rules  governing  medical
         products in the European Community 1989);

 2.8     "Claims"  means  any and all  claims,  demands,  losses,  obligations,
         liabilities, damages, deficiencies,  actions, settlements,  judgments,
         cost  and  expenses  which a Party  may  incur  or  suffer  (including
         reasonable  costs  and  legal  fees  incident  thereto  or in  seeking
         indemnification therefor);

 2.9     "Costs" means the costs for the Project, which costs shall exclude the
         Price but shall include the costs of raw materials,  filters,  resins,
         Product release testing, external testing, any royalties to be paid to
         third parties, subcontractor costs, out of pocket expenses, travel and
         lodging costs, capital investments, shipping Product, insuring shipped
         Products,  and all brokers fees, customs duties, import duties, excise
         taxes and other  taxes  payable in  connection  with the  delivery  of
         Product;

 2.10    "CYTOGEN" means Cytogen Corporation;


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<PAGE>
 2.11    "CYTOGEN Proprietary Information" has the meaning ascribed thereto in
         Section 14.1;

 2.12    "CYTOGEN Technology" means any and all current and future Intellectual
         Property Rights proprietary to CYTOGEN in so far as provided, granted,
         divulged or disclosed, either directly or indirectly by CYTOGEN to DSM
         Biologics, pertaining to the Project.

 2.13    "Defaulting Party" has the meaning ascribed thereto in Section 15.3;

 2.14    "Documents" means the Specifications,  Bill of Testing, Batch Records,
         certificate  of  analysis  containing  the outcome of the tests on the
         Product and Release statement;

 2.15    "DSM Biologics" means DSM Biologics Company B.V.;

 2.16    "DSM   Biologics   Technology"   means   any  and  all   current   and
         future-Intellectual Property Rights proprietary to DSM Biologics in so
         far as provided,  granted,  divulged or disclosed,  either directly or
         indirectly,  by DSM  Biologics to CYTOGEN in the process of performing
         the  Project,   pertaining  to  fermentation,   primary  recovery  and
         purification of biopharmaceutical products;

 2.17    "Force Majeure" has the meaning ascribed thereto in Section 20.1;

 2.18    "Intellectual  Property  Rights"  means,  whether or not  protected or
         protectible   under  any   particular   law,   all   patents,   patent
         applications,  patentable  subject matter,  copyrights,  copyrightable
         subject matter,  ideas,  inventions,  discoveries,  devices,  designs,
         apparatuses,  practices,  processes,  methods,  products,  cell lines,
         progeny,  engineered  cell  lines,  clones,  samples,  trade  secrets,
         technology, know-how, software, hardware, improvements, trademarks and
         service marks (and the goodwill pertaining thereto);

 2.19    Letter of Commitment" means the letter agreement entered into between
         the  Parties  dated  January  26,  2000  for the  commencement  by DSM
         Biologics of some development activities for the Product cell line;

 2.20    "Manufacturing  Instructions"  means the protocols  for  manufacturing
         Product  in Step 5 and  all  amendments  thereto,  to be  agreed  upon
         between the Parties.  It is understood  between the Parties that these
         protocols may be amended at all times,  including during manufacturing
         of Product;

 2.21    "Parties" means DSM Biologics and CYTOGEN collectively;

 2.22    "Party" means either DSM Biologics or CYTOGEN;


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<PAGE>





2.23     "Price"  means the price for the  Project  as  specified  in Section 6,
         which price shall exclude Costs;

2.24     "Process"  means the  stirred  tank  perfusion  bioreactor  process  to
         manufacture  Product,  as  well as  purification  and  conjugation,  if
         reduced to practice as a result of Step 1 and Step 4 of the Project;

2.25     "Product" means purified bulk conjugated antibody known by CYTOGEN as
         CYT 356;

2.26     "Project" means development-, upscaling-, cell banking-, manufacturing-
         and validation  activities,  and providing  regulatory  support, by DSM
         Biologics,  comprising  of Step 1,  Step 2,  Step 3, Step 4, Step 5 and
         Step 6 as further  described in the Schedule annexed hereto and being a
         part hereof, and all amendments thereto, to be agreed upon between the
         Parties;

2.27     "Project  Manager" means the  individual  assigned by DSM Biologics who
         will  be  responsible  for  the  scientific  management  and  technical
         components of the Project;

2.28     "Release"  means that,  after Product has been  manufactured in Step 5,
         the Product meets the Specifications and was manufactured  according to
         cGMP and the Manufacturing Instructions;

2.29     "Specifications"  means  the  specifications,   technical  data  and/or
         formulae  of the  Product  manufactured  in Step 5, and all  amendments
         thereto, to be agreed upon between the Parties;

2.30     "Steering Committee" means a committee with an equal number of
         representatives from each Party;

2.31     "Step 1" means  developing  a  Process  under  non-cGMP  conditions  by
         adapting  the  CYTOGEN   Product  cell  line  to  a  serum  free  media
         formulation  and by  performing  upstream  and  downstream  development
         activities,  including a seven (7) liter  fermentation  run and a fifty
         (50) liter so called  pilot  fermentation  with a lab scale down stream
         processing step and conjugation;

2.32     "Step 2" means transfer, development and optimization of CYTOGEN
         quality control assays;

2.33     "Step 3" means preparing under cGMP conditions a master cell bank and a
         manufacturer working cell bank


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<PAGE>

2.34     "Step 4" means using the Process as  developed  in Step I to perform at
         fifty (50) liter scale,  under non-cGMP  conditions,  one (1) so cal1ed
         shakedown run including one (1) conjugation;

2.35     "Step 5" means cGMP  manufacturing  three (3) batches of Product  using
         the Process for a Biologics  License  Application  (BLA) supplement and
         market distribution;

2.37     "Step 6" means:

         i)       writing a Process and assay master validation plan and
                  subsequently executing this plan during the performance of
                  Step 5;
         ii)      means  providing  support  for  CYTOGEN's   preparation  of  a
                  chemistry  manufacturing  and control  (CMC) data  package for
                  filing the Process for a United  States BLA  supplement  and a
                  European Marketing Authorization Application (MAA) supplement.


SECTION 3 - OBJECTIVES AND OBLIGATIONS OF THE PARTIES
-----------------------------------------------------

3.1      It is the  intention  of the Parties to hereby  establish a lasting and
         mutually  profitable  relationship  and for that  purpose to inform and
         assist one another in a spirit of co-operation  during the execution of
         the Project.

3.2      Subject to the terms and conditions of this  Agreement,  CYTOGEN hereby
         engages  DSM  Biologics  to carry out the  Project  and DSM  Biologics,
         subject  to  the  terms  and  conditions  of  this  Agreement,   hereby
         undertakes to use its best reasonable  efforts to carry out the Project
         in accordance with the Schedule annexed hereto and being a part hereof.

3.3      The Parties  hereby  acknowledge  and agree  that  there is  absolutely
         no guarantee:
         i.)      that the Product and the Process will be commercially
                  exploitable, profitable or approved by any regulatory
                  authority;
         ii.)     that the milestones identified in the Schedule to this
                  Agreement for Step 1, Step 2 and Step 4 will be achieved;
         iii.)    that any Product resulting from Step 1 or Step 4 will fulfill
                  certain specifications, certain yields or will be delivered in
                  time for any further use intended therefor by CYTOGEN; or
         iv.)     that the Product to be manufactured in Step 5 will be
                  delivered in time for a BLA and MAA supplement submission and
                  approval or for market distribution.

3.4      CYTOGEN shall timely provide all CYTOGEN Technology necessary for the
         performance of the Project as well as, if so
         requested by DSM Biologics,


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<PAGE>

         provide  reasonable  technical  assistance needed by DSM Biologics for
         the performance of the Project.

         Any material  change to the scope of the Project shall not take effect
         unless approved in writing by CYTOGEN through a CCN.

         The  Parties  acknowledge  that this  Agreement  is only for  certain
         development  activities  and the  delivery  of three (3)  batches  of
         Product and not for commercially  manufacturing  Product.  Therefore,
         during the performance of Step 5 of the Project, the Parties shall in
         good faith  negotiate a long term supply  agreement in respect of the
         Product under the proviso that the  aforementioned  three (3) batches
         comply with the  Specifications  and that all  relevant  governmental
         authority  is  granted  to  commercially  use the  Product  on  human
         subjects.  If the  Parties  do not enter into such an  agreement,  at
         CYTOGEN's   request,   the   Parties   will  enter  into  good  faith
         negotiations  for CYTOGEN to - license the DSM  Biologics  Technology
         pursuant to a license  agreement on terms and conditions to be agreed
         upon.  Such  terms  and  conditions  shall be as  competitive  as DSM
         Biologics offers to any third party.

         The Parties will elect, at their convenience,  a Steering  Committee,
         that will  oversee  the  general  execution  of the  Project  and the
         Agreement  and will  discuss,  both  during  the  performance  of the
         Project and after  completion  of the Project,  the further  plans of
         CYTOGEN  for the Product and the  Process,  including  the status and
         outcome  of  clinical  trials,  registration  activities  and  future
         requirements  by CYTOGEN of Product,  whether  for  further  clinical
         trials or for marketing.

SECTION 4 - STEP 1, STEP 2, STEP 3 AND STEP 4 OF THE PROJECT
------------------------------------------------------------

4.1      The  different  parts of the  Project  are  estimated  to require  the
         periods of time  identified  in the  Schedule to this  Agreement.  DSM
         Biologics  shall timely notify CYTOGEN if it expects  performance of a
         part  of the  Project  not to be  possible  within  the  timeframe  as
         described in the Schedule,  and shall take all  reasonable  efforts to
         perform that part of the Project as soon as possible thereafter.


4.2      The  Parties  shall,  during and after  completion  of Step 1,  discuss
         whether the milestones identified in the Schedule to this Agreement for
         Step 1 have been achieved and shall, based upon such discussion, decide
         on whether to perform  additional  work with regard to Step 1,  proceed
         with Step 2 according to the Schedule or terminate the Project.  If the
         Parties  decide to perform  additional  work with regard to Step 1, the
         duration,  scope,  price and costs thereof  shall be separately  agreed
         upon between the Parties.

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<PAGE>

4.3      During  the  performance  and after  completion  of Step 2, if and when
         performed,  the Parties shall, based upon the milestones  identified in
         the Schedule to this Agreement for Step 2, decide on whether to perform
         additional work with regard to Step 2, proceed with Step 4 according to
         the Schedule or terminate the Project. If the Parties decide to perform
         additional work with regard to Step 2, the duration,  scope,  price and
         costs thereof shall be separately agreed upon between the Parties.

4.4      If the  Parties  agree Step 3 is  necessary,  and as  described  in the
         Schedule  to  this   Agreement,   DSM  Biologics  shall  commence  with
         performing Step 3 of the Project as outlined in the Schedule.

4.5      During  the  performance  and after  completion  of Step 4, if and when
         performed,  the Parties shall, based upon technical reasons such as the
         robustness of the Process, decide on whether to perform additional work
         with regard to Step 4, proceed with Step 5 according to the Schedule or
         terminate the Project. If the Parties decide to perform additional work
         with regard to Step 4, the  duration,  scope,  price and costs  thereof
         shall be separately agreed upon between the Parties.

SECTION 5 - STEP 5 AND STEP 6 OF THE PROJECT
--------------------------------------------

5.1      DSM Biologics  shall commence with  performing Step 5 of the Project if
         and when the Parties  decide  thereto  according  to Section  4.5.  DSM
         Biologics shall timely notify CYTOGEN if it expects delivery of Product
         not to be possible  within the  timeframe  described in the Schedule to
         this  Agreement,  and shall take all efforts to deliver Product as soon
         as possible thereafter.

5.2      The Product shall be manufactured in accordance with the  Manufacturing
         Instructions and under cGMP  conditions.  Each batch of Product will be
         sampled and tested by the quality  control  department of DSM Biologics
         against the  Specifications.  The quality  assurance  department of DSM
         Biologics  will  review  the  Batch  Records  and  will  assess  if the
         manufacturing  has taken  place in  compliance  with the  Manufacturing
         Instructions and cGMP regulations.

5.3      If  based  upon  such  tests,  a  batch  of  Product  conforms  to the
         Specifications  and  was  manufactured   according  to  cGMP  and  the
         Manufacturing Instructions,  a Release statement will be completed and
         approved by the quality  assurance  department of DSM Biologics.  This
         certificate  together  with all other  Documents  will be delivered to
         CYTOGEN or a third party  appointed  by Cytogen.  The batch of Product
         will be  delivered  to CYTOGEN or a third party  appointed by Cytogen.
         DSM  Biologics  shall retain  sample of the batch to be delivered  and
         shall have the batch shipped and insured according to


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<PAGE>
         CYTOGEN's  instructions.  Responsibility for the batch shall pass after
         delivery by DSM  Biologics  of the batch to the carrier (CIP as defined
         in the INCO Terms 1990).

5.4      CYTOGEN  will  test the batch for  compliance  with the  Specifications
         through analyzing the Documents delivered by DSM Biologics,  within two
         (2) weeks of  delivery  of the  Documents  and will Accept the batch in
         case of such  compliance  ("Acceptance").  CYTOGEN has no obligation to
         accept the batch if such batch does not comply with the Specifications.
         CYTOGEN  will  notify DSM  Biologics  in writing of its  Acceptance  or
         rejection  of the  batch  within  two  (2)  weeks  of  delivery  of the
         Documents.  In the  absence  of any such  written  confirmation  to DSM
         Biologics,  the batch shall be deemed to comply with the Specifications
         and  Accepted  by  CYTOGEN.  During  the  aforementioned  two (2) weeks
         CYTOGEN  shall  store  or  have  stored  the  batch-  under  controlled
         conditions.

5.5      If there is any dispute  concerning  whether Product  complies with the
         Specifications  or not or whether  such  failure is due (in whole or in
         part) to acts or  omissions  of  CYTOGEN  or a CYTOGEN  designee  after
         delivery  of  Product,  a sample of the  rejected  Product and a sample
         retained by DSM Biologics as set forth above shall be exchanged between
         CYTOGEN and DSM Biologics for a counter  check.  If such  counter-check
         does not resolve the dispute,  a sample of the  rejected  Product and a
         sample  retained by DSM Biologics shall be submitted to an independent,
         qualified  third-party  laboratory  that  is  mutually  acceptable  and
         selected by the Parties  promptly in good faith.  Such laboratory shall
         determine  whether the rejected Product met the  Specifications  at the
         time of delivery to the  carrier and such  laboratory's  determinations
         shall be final and  determinative  for purposes of this  Agreement save
         for manifest error on the face of decision.  The Party against whom the
         laboratory  rules  shall bear all costs of the  third-party  laboratory
         activities.

5.6      If a batch of Product does not conform to the Specifications,  and this
         nonconformity  is not due to DSM Biologics'  failure to comply with the
         Manufacturing  Instructions or with cGMP, CYTOGEN shall have to pay the
         Price  and  Costs  for this  batch.  DSM  Biologic  shall at  CYTOGEN's
         request, cost and expense,  either obtain new raw materials and produce
         a new batch of Product  as soon as  reasonably  possible  or rework the
         batch.

5.7      Regardless of whether a batch of Product conforms to the Specifications
         or not, if this batch was not manufactured according to cGMP and/or the
         Manufacturing  Instructions,  thereby making the Product unsuitable for
         its intended purpose, CYTOGEN shall not have to pay the Price and Costs
         for this batch.  DSM  Biologics  shall at CYTOGEN's  request,  cost and
         expense, obtain new raw materials and produce a new batch of Product as
         soon as reasonably  possible.  However,  in the event it is possible to
         rework the Product in such a


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<PAGE>
         way that the batch can be deemed to have been manufactured according to
         cGMP and the Manufacturing Instructions, then CYTOGEN shall have to pay
         the  Price and  Costs  for  batch of  Product  but not the costs of the
         reworking, which shall be for DSM Biologics' account.

5.8      The Parties shall in good faith separately agree upon the scope of work
         for Step 6, the commencement date and expected duration, and the price
         and costs thereof.

SECTION 6 - PRICE AND COSTS
---------------------------

6.1      It is  understood  between the  Parties  that the Price for the Project
         shall be based upon the  assumptions  contained in the Schedule  hereto
         and  the  limited  information  available  to DSM  Biologics  up to the
         effective date of this Agreement. If, during the preparation for or the
         performance of the Project,  itbecomes clear that these assumptions are
         not  correct,  and have  consequences  for the Project  which cannot be
         dealt with through a CCN, or the detailed information further exchanged
         between the Parties  indicates more labor and/or occupancy is needed to
         perform the Project,  the Parties shall  renegotiate  the Price in good
         faith.  ID addition,  the Price for Step 4 and Step 5 is based upon the
         expected process steps to be defined in the Process.  Should the Step 1
         and/or Step 4 activities lead to a Process which differs  significantly
         in the expected  number of process  steps and/or the time for executing
         the  Process,  the  Price  for  Step 4 and  Step 5  shall  be  adjusted
         accordingly.

6.2      The Price, excluding VAT, for the work to be performed in Step 1 of the
         Project  shall be ***** United States  dollars (US $ *****).  Under the
         Letter of Commitment, Cytogen has paid an amount of ***** United States
         dollars (US $ *****) as an upfront  payment for the  performance by DSM
         Biologics  of Step 1. The  remainder  of the  Price,  including  VAT if
         applicable,  for Step 1, being ***** United States dollars (US $ *****)
         shall be invoiced as follows:
         i.)      *****  United  States  dollars (US $*****)
                  upon completion of the seven (7) liter fermentation run in
                  Step 1;
         ii)      ***** United States dollars (US $ *****)
                  upon  completion  in Step 1 of the fifty  (50) liter so called
                  pilot  fermentation  with a lab scale down  stream  processing
                  step and conjugation.

6.3      The Price,  excluding  VAT,  for the work  performed  in Step 2 of the
         Project shall be based on ***** United States dollars (US $ *****) per
         hour worked.


-----------------------------
*****  Confidential portion omitted and filed separately with the Securities and
Exchange Commission


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<PAGE>
                  This Price,  including  VAT if  applicable,  shall be invoiced
                  every  month  based  on  the  actual  man-hours  spent  by DSM
                  Biologics in the previous month on performing Step 2.


6.4      The  Price,  excluding  VAT,  for the work  performed  in Step 3 of the
         Project shall be ***** United States  dollars (US $*****).  This Price,
         including VAT if  applicable,  shall be invoiced to and paid by CYTOGEN
         as  follows:  i)  *****  percent  (*****  %) one  (1)  month  prior  to
         commencement  of Step 3; ii) *****  percent  (***** %) at completion of
         Step 3.

6.5      The Price, excluding VAT, for the work performed in Step 4 of the
         project shall be ***** United States dollars (US $ *****).  This Price,
         including VAT if applicable, shall be invoiced to and paid by CYTOGEN
         as follows:
         i)       ***** percent (***** %) one (1) month prior to commencement of
                  Step 4;
         ii)      ***** percent (***** %) at completion of fermentation;
         iii)     ***** percent (***** %) at complexion of downstream
                  processing;
         iv)      ***** percent (***** %) upon delivery by DSM Biologics of any
                  resulting Product.

6.6      The Price,  excluding VAT, for the cGMP batches of Product manufactured
         in Step 5 of the Project  shall be *****  United  States  dollars (US $
         *****) per batch. The total Price for  manufacturing  three (3) batches
         of Product shall thus be ***** United States dollars (US $ *****).

         The Price per batch of Product, including VAT if applicable, shall be
         invoiced to and paid by CYTOGEN as follows:
         iii)     ***** percent (***** %) one (1) month prior to commencement of
                  the manufacture of the Product;
         iv)      ***** percent (***** %) at completion of fermentation of the
                  Product;
         v)       ***** percent (***** %) at completion of downstream processing
                  the Product;
         vi)      ***** percent (***** %) upon delivery by DSM Biologics of
                  Product, all related Documents and Acceptance.

6.7      The Price, excluding VAT, for Step 6 of the Project shall separately be
         agreed upon in good faith between the Parties.



-----------------------------
*****  Confidential portion omitted and filed separately with the Securities and
Exchange Commission


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<PAGE>

6.8      The Costs  for the  Project,  including  VAT if  applicable,  shall be
         invoiced  to and  paid by  CYTOGEN  when  the  Costs  are  made by DSM
         Biologics.  However,  in respect of raw materials,  CYTOGEN shall, two
         (2) months prior to commencement of Step 5, make an advance payment of
         ***** United States  dollars (US $ *****),  which amount DSM Biologics
         shall use to pay the first  invoices  for raw  materials to be ordered
         for Step 5.

6.9      All invoices  shall be payable by CYTOGEN  within  thirty (30) days of
         receipt of an invoice into the bank account  specified on the invoice.
         Any delay in the  payment by  CYTOGEN  of the Price  and/or the Costs,
         except in the event of a dispute  in respect  of Price  and/or  Costs,
         shall carry an interest  rate as of the first day of delayed  payment,
         which  interest  rate  shall be based  on a  annual  interest  rate of
         fifteen percent (15%).

SECTION 7 - MANAGEMENT OF THE PROJECT
-------------------------------------

7.1      The Parties hereby agree that the Project shall be under the day-today
         supervision of a Project Manager.

7.2      The Parties  shall work in  conjunction  with the  Project  Manager to
         ensure the satisfactory performance of the Project.

7.3      The Project  Manager shall be entitled to propose  recommendations  to
         the Parties to ensure that the Project meets its objectives.

7.4      The  Project  Manager  shall  be  in  charge  of  all  managerial  and
         scientific  aspects of the  Project and shall  maintain  communication
         with the Parties in connection therewith.

7.5      DSM Biologics  shall permit any individual so authorized by CYTOGEN to
         visit,  during regular  business hours,  the site where the Project is
         being  conducted to evaluate the progress  thereof,  unless such visit
         would  conflict  with a  prearranged  visit by  another  client  or an
         inspection by or for another client. Except in exigent  circumstances,
         said  visit  shall be made  subject  to ten (10)  days  notice  of the
         requirement of such visit, such notice to be given to DSM Biologics by
         CYTOGEN.

7.6      The  Parties  may  use  electronic  mail  to  communicate  during  the
         performance  of the  Project.  The  Parties  shall use all  reasonable
         measures to ensure the confidentiality of information so communicated.


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*****  Confidential portion omitted and filed separately with the Securities and
Exchange Commission


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SECTION 8 - RECORDS AND REPORTS
-------------------------------

DSM Biologics hereby undertakes that it shall have the Project Manager submit to
CYTOGEN,  after  completion of Step 1 and Step 2 a report detailing the progress
and results of these Steps and highlighting any major issues  encountered during
the previous period.

SECTION 9 - AUDITS AND CYTOGEN REGULATORY APPROVALS
---------------------------------------------------

9.1      DSM  Biologics  grants  CYTOGEN the right to audit or to appoint  third
         parties to audit, under applicable  confidentiality  provisions, at any
         reasonable time, the facilities employed and the documentation utilized
         by  DSM  Biologics  for  performing  the  Project.  Except  in  exigent
         circumstances,  CYTOGEN will notify DSM  Biologics at least twenty (20)
         business  days in advance of such an audit by CYTOGEN  and thirty  (30)
         business  days in  advance of such an audit by a third  party.  All DSM
         Biologics'  expenses  associated  with  such  audits  shall be borne by
         CYTOGEN.

9.2      DSM  Biologics  permits  inspections  of DSM  Biologics'  facilities by
         governmental authorities (such as the United States of America Food and
         Drug Administration and equivalent European regulatory authorities) for
         any registration or pending  registration for manufacturing of Product.
         All DSM Biologics'  expenses associated with inspections as they relate
         directly to manufacturing of Product shall be borne by CYTOGEN.

SECTION 10 - SUBCONTRACTING
---------------------------

DSM Biologics shall be entitled to subcontract  portions of the Project to those
subcontractors  identified in the Schedule to this Agreement.  In addition,  DSM
Biologics  shall be  entitled  to  subcontract  any  portion of its  obligations
hereunder to its Affiliates.  Subcontracting  by DSM Biologics of any portion of
its  obligations  hereunder to any other third party  requires  CYTOGEN's  prior
written  permission  thereto  which  permission  shall  not be  unreasonably  or
untimely withheld.

SECTION 11 - INTELLECTUAL PROPERTY RIGHTS
-----------------------------------------

11.1     CYTOGEN declares that it has the full right and title to make available
         the CYTOGEN  Technology to DSM Biologics.  DSM Biologics  shall use the
         CYTOGEN Technology solely to perform the Project.


                                       12

<PAGE>
11.2     CYTOGEN  Technology  shall  remain the sole and  exclusive  property of
         CYTOGEN.  All DSM  Biologics  Technology  shall  remain  the  sole  and
         exclusive  property of DSM Biologics.  The Product  manufactured in the
         Project,  the Documents and the reports  referred to in Section 8 shall
         be the sole and  exclusive  property of CYTOGEN and all rights and tide
         thereto  shall  vest in and to  CYTOGEN.  In  addition,  CYTOGEN  shall
         exclusively  own  all  Intellectual  Property  Rights  obtained  in the
         Project  specifically  related to the Process.  DSM Biologics shall, as
         soon as possible,  execute and do all instruments and things reasonably
         necessary  to transfer  or vest such  Intellectual  Property  Rights in
         CYTOGEN. DSM Biologics shall, however, have the right to freely use all
         Intellectual  Property  Rights  obtained  in the Project in the general
         field  of   fermentation,   primary   recovery  and   purification   of
         biopharmaceutical products.

SECTION 12 - WARRANTY, LIABILITY AND INDEMNIFICATION
----------------------------------------------------

12.1     DSM Biologics does not grant any warranty, either expressed or implied,
         legal  or  conventional,  with  regard  to the  Project  other  than as
         explicitly  contained or  incorporated  in this Agreement and disclaims
         all implied warranties of merchantability  and fitness for a particular
         purpose  except  to the  extent of DSM  Biologics'  own  processes  and
         facilities.  DSM  Biologics  in  particular  does not  warrant,  either
         expressed  or implied,  that the  performance  by it of the  activities
         contemplated  by the Project in accordance with this Agreement will not
         infringe upon Intellectual Property Rights of any third party.

12.2     DSM Biologics shall indemnify, defend and hold harmless CYTOGEN against
         and in respect of any and all Claims arising out of or based upon:
         i)       the breach by DSM Biologics of any representations,
                  warranties, covenants or terms contained or incorporated in
                  this Agreement; or
         ii)      any gross negligence or willful misconduct by DSM Biologics or
                  its  employees,  agents,  sub-contractors  or suppliers of raw
                  materials in connection  with the  performance of the Project;
                  except to the extent of Claims  being due to  CYTOGEN's or its
                  supplier's negligence or fault and provided that DSM Biologics
                  shall  not  be  liable  for  any  consequential,  indirect  or
                  exemplary  damages  suffered by CYTOGEN and  provided  further
                  that the total of any damages, other than as to Claims against
                  CYTOGEN for personal injury, to be paid by DSM Biologics shall
                  not exceed the Price.

         DSM Biologics shall, at the request of CYTOGEN,  assume the defense of
         any demand,  claim, action, suit or proceeding brought against CYTOGEN
         by reason of the foregoing and shall pay any and all damages up to the
         Price that are


                                       13
<PAGE>
         assessed or that are payable by CYTOGEN as a result of the  disposition
         of any such demand, claim, action, suit or proceeding.  Notwithstanding
         the foregoing,  CYTOGEN may be represented in any such action,  suit or
         proceeding at its own expense and by its own counsel.

12.3     CYTOGEN shall indemnify, defend and hold harmless DSM Biologics against
         and in respect of any and all Claims arising out of or based upon:
         i)       the breach by CYTOGEN of any representations, warranties,
                  covenants or terms contained or incorporated in this
                  Agreement; or
         ii)      any gross  negligence or willful  misconduct by CYTOGEN or its
                  employees, agents, or suppliers of raw materials in connection
                  with the performance of the Project;
         except  to the  extent of Claims  being  due to DSM  Biologics'  or its
         supplier's  negligence  or fault and provided that CYTOGEN shall not be
         liable for any consequential, indirect or exemplary damages suffered by
         DSM Biologics and provided further that the total of any damages, other
         than as to Claims against DSM Biologics for personal injury, to be paid
         by CYTOGEN shall not exceed the Price.

12.4     CYTOGEN shall, at the request of DSM Biologics'  assume the defense of
         any demand,  claim,  action,  suit or proceeding  brought  against DSM
         Biologics by reason of the foregoing and shall pay any and all damages
         up to the Price that are assessed or that are payable by DSM Biologics
         as a result of the disposition of any such demand, claim, action, suit
         or proceeding.  Notwithstanding  the  foregoing,  DSM Biologics may be
         represented in any such action,  suit or proceeding at its own expense
         and by its own counsel.

         Furthermore,  CYTOGEN  agrees to indemnify  DSM Biologics and save and
         hold it harmless from and against any Claims which DSM Biologics is or
         may become liable for or may incur or may be called upon to pay or may
         pay  and  that   result  from  or  are  alleged  to  result  from  the
         infringement  of any  Intellectual  Property Rights through the use by
         DSM  Biologics or its  subcontractors  of CYTOGEN  Technology,  or the
         development,   use  or   manufacturing   by  DSM   Biologics   or  its
         subcontractors  of the  Process  or the  Product,  provided  that  DSM
         Biologics notifies CYTOGEN immediately of any demand,  claim,  action,
         suit or other  proceeding.  CYTOGEN  shall  however  not be  liable to
         indemnify or hold harmless DSM Biologics for payment of any settlement
         unless . : CYTOGEN has consented to the settlement.

         CYTOGEN shall,  at the request of DSM Biologics,  assume the defense of
         any demand,  claim,  action,  suit or  proceeding  brought  against DSM
         Biologics  by  reason  of the  foregoing  and pay  any and all  damages
         assessed  or that are  payable  by DSM  Biologics  as a  result  of the
         disposition of any such demand, claim, action, suit or proceeding.
         Notwithstanding the foregoing, DSM


                                       14
<PAGE>
         Biologics may be represented in any such action,  suit or proceeding at
         its own expense and by its own counsel.

12.5     DSM  Biologics  agrees  to  indemnify  CYTOGEN  and  save  and hold it
         harmless  from and against any Claims  which  CYTOGEN is or may become
         liable  for or may incur or may be  called  upon to pay or may pay and
         that result from or are alleged to result from the infringement of any
         Intellectual  Property  Rights through the use by DSM Biologics or its
         subcontractors of DSM Biologics  Technology for the Project,  provided
         that CYTOGEN notifies DSM Biologics  immediately of any demand, claim,
         action,  suit or other proceeding.  DSM Biologics shall however not be
         liable to  indemnify  or hold  harmless  CYTOGEN  for  payment  of any
         settlement unless DSM Biologics has consented to the settlement.

         DSM Biologics  shall, at the request of CYTOGEN,  assume the defense of
         any demand,  claim,  action, suit or proceeding brought against CYTOGEN
         by reason of the foregoing and pay any and all damages assessed or that
         are  payable  by  CYTOGEN  as a result of the  disposition  of any such
         demand,   claim,  action,  suit  or  proceeding.   Notwithstanding  the
         foregoing.  CYTOGEN  may be  represented  in any such  action,  suit or
         proceeding at its own expense and by its own counsel.

SECTION 13 - REPRESENTATIONS AND WARRANTIES
-------------------------------------------

13.1     DSM Biologics hereby  represents and warrants to CYTOGEN that:
         i)       it is a corporation duly organized, validly existing and in
                  good standing under the laws of The Netherlands,  and has full
                  corporate  power  to  conduct  the  business  in  which  it is
                  presently   engaged   and  to  enter  into  and   perform  its
                  obligations under this Agreement;
         ii)      it has  taken  all  necessary  corporate  action  under  the
                  applicable laws and its articles of incorporation and bylaws
                  to authorize the execution by its  undersigned  officers and
                  consummation of this Agreement. This Agreement constitutes a
                  valid and legally binding agreement,  enforceable against it
                  in  accordance  with  its  terms,   subject  to  bankruptcy,
                  insolvency, fraudulent transfer, reorganization,  moratorium
                  and  similar  laws of general  applicability  relating to or
                  affecting   creditors'   rights   and  to   general   equity
                  principles;
         iii)     the performance by it of its obligations contemplated by the
                  Project in accordance  with this  Agreement will not violate
                  the terms of any other  agreement  to which it is subject to
                  or by which it is bound;
         iv)      it has  the  right  and  power  to  perform  the  activities
                  contemplated by the Project;


                                       15
<PAGE>
         v)       it will not use in any capacity, in connection with performing
                  the Project,  any individual who has been debarred pursuant to
                  the United States Federal Food, Drug and Cosmetic Act; and
         vi)      to its  knowledge,  the  performance  by it of the  activities
                  contemplated  by the Project in accordance with this Agreement
                  will not conflict with any law or regulation applicable to DSM
                  Biologics.

13.2     CYTOGEN hereby represents and warrants to DSM Biologics that:
         i)       it is a corporation  duly organized,  validly  existing and in
                  good  standing  under  the  laws of New  Jersey,  and has full
                  corporate  power  to  conduct  the  business  in  which  it is
                  presently   engaged   and  to  enter  into  and   perform  its
                  obligations under this Agreement:
         ii)      it has  taken  all  necessary  corporate  action  under  the
                  applicable laws and its articles of incorporation and bylaws
                  to authorize the execution by its  undersigned  officers and
                  consummation of this Agreement. This Agreement constitutes a
                  valid and legally binding agreement,  enforceable against it
                  in  accordance  with  its  terms,   subject  to  bankruptcy,
                  insolvency, fraudulent transfer, reorganization,  moratorium
                  and  similar  laws of general  applicability  relating to or
                  affecting   creditors'   rights   and  to   general   equity
                  principles;
         iii)     the performance by it of its obligations contemplated by the
                  Project in accordance  with this  Agreement will not violate
                  the terms of any other  agreement  to which it is subject to
                  or by which it is  bound;  iv) it has the right and power to
                  perform the activities  contemplated by the Project;  and v)
                  to its  knowledge,  the  performance by it of the activities
                  contemplated   by  the  Project  in  accordance   with  this
                  Agreement  will  not  conflict  with  any law or  regulation
                  applicable to CYTOGEN.

SECTION 14 - CONFIDENTALITY
---------------------------

14.1     Unless  agreed to  otherwise in this  Agreement,  DSM  Biologics  shall
         maintain the confidentiality of the CYTOGEN Technology,  the Documents,
         the reports  referred to in Section 8, the  Manufacturing  Instructions
         and the Process  (jointly the "CYTOGEN  Proprietary  Information")  and
         CYTOGEN  shall  maintain  the  confidentiality  of  the  DSM  Biologics
         Technology,  and the  Parties  shall not in any way or at any time make
         use  thereof  for any  purpose  other than  pursuant to and in order to
         carry out the terms and objectives of this Agreement.

14.2     DSM Biologics' obligations contained in Section 14.1 shall not apply to
         CYTOGEN Proprietary Information, and CYTOGEN's obligations contained in
         Section 14.1 shall not apply to DSM Biologics Technology which:


                                       16
<PAGE>

         i)       at the time of disclosure either is or was part of the public
                  knowledge or literature;
         ii)      after  disclosure  becomes  part of the  public  knowledge  or
                  literature through no fault or action of the receiving Party;
         iii)     the receiving Party can establish by competent proof either is
                  or was at the time of disclosure in its lawful possession from
                  a source other than the disclosing Party;
         iv)      after  disclosure  is acquired by the  receiving  Party from a
                  third  party  who  did not  obtain  such  CYTOGEN  Proprietary
                  Information respectively DSM Biologics Technology, directly or
                  indirectly, from the disclosing Party;
         v)       is independently developed by CYTOGEN or DSM Biologics without
                  the use of DSM Biologics Technology respectively CYTOGEN
                  Proprietary Information:

14.3     The obligations set forth under Section 14.1 shall,  furthermore,  not
         apply to CYTOGEN Proprietary  Information or DSM Biologics  Technology
         which the receiving  Party is required to disclose in  prosecuting  or
         defending  litigation  or in complying  with  applicable  governmental
         regulations in such case  reasonable  advance notice shall be given to
         the disclosing Party.

14.4     DSM Biologics shall not disclose CYTOGEN  Proprietary  Information and
         CYTOGEN  shall not disclose DSM  Biologics  Technology  to any persons
         other  than  to  its  shareholders,   Affiliates,  agents,  employees,
         consultants,   subcontractors  and  other  authorized  representatives
         necessarily  connected  with the  Project.  From all such  persons the
         Parties  will,  prior to his or her  receipt  of  CYTOGEN  Proprietary
         Information respectively DSM Biologics Technology, obtain undertakings
         to maintain the confidentiality of any such disclosure  containing the
         obligations as set forth in Section 14.1.

14.5     The obligations as set forth in this Section 14 shall expire five (5)
         years from the date this Agreement terminates.

14.6     The  provisions  of this  Section 14  replace  and annul the terms and
         conditions of the mutual  confidential  disclosure  agreement  entered
         into on  October  8,  1998 by  CYTOGEN  and DSM  Biologics'  Affiliate
         Gist-Brocades/Bio-Intermediair  Inc., now named DSM Biologics  Company
         Inc.

SECTION 15 - TERM AND TERMINATION
---------------------------------

15.1     This  Agreement  shall enter into force as of the date it is signed by
         both  Parties and shall remain in effect until the earlier date of the
         Project being  completed or the Agreement  being  terminated by either
         Party as provided herein. As per the


                                       17
<PAGE>
         date  this  Agreement  enters into force, the  Letter of Commitment
         shall terminate.

15.2     This Agreement  shall  terminate if a go/no go decision to be taken in
         accordance with the Schedule to this Agreement is a no go decision. In
         such event the Agreement  shall  terminate as per the date the Parties
         take this decision.  In the event of such  termination,  CYTOGEN shall
         compensate DSM Biologics for the following costs: i) the Price for all
         work  performed  in the  Project  up to the date of  termination;  ii)
         close-out costs being the Price for the work that is scheduled for the
         three (3) months  following the date of termination as detailed in the
         Schedule.  CYTOGEN  however  retains the right to have such  scheduled
         work  performed in those three (3) months.  In the event  CYTOGEN does
         not make use of this right,  and DSM  Biologics is able to resell part
         or whole of this  three  (3)  month  capacity  to a third  party,  DSM
         Biologics  will so  inform  CYTOGEN  and  will  provide  a good  faith
         discount  to  CYTOGEN  in respect  of the  close-out  costs;  iii) raw
         materials  and supplies  already  ordered by DSM  Biologics  iv) third
         party  commitments,  such as in respect of external  testing,  already
         entered into by DSM Biologics.

15.3     Either Party shall have the right to terminate this Agreement in the
         event that:
         i)       the other Party (the  "Defaulting  Party")  fails to perform
                  any material obligations,  warranty,  duty or responsibility
                  or is in  default  with  respect  to any  material  term  or
                  condition  undertaken  by the  Defaulting  Party  under this
                  Agreement and such failure or default  continues  unremedied
                  for a period  of  ninety  (90)  days  after  written  notice
                  thereof  by the  aggrieved  Party to the  Defaulting  Party;
                  provided  that if such  breach  cannot be  reasonably  cured
                  within  ninety (90) days,  such breach shall be deemed cured
                  if the Defaulting Party commences to cure such breach within
                  such ninety (90) day period and  diligently  continues  such
                  cure and no  material  adverse  impact  will result from the
                  delay;  ii) the  Defaulting  Party  is  affected  by a Force
                  Majeure  which cannot be removed,  overcome or abated within
                  six (6) months (or such-other  period as the Parties jointly
                  shall  determine)  from the date the Defaulting  Party first
                  became affected; or
         iii)     the Defaulting Party ceases or takes material steps to cease
                  carrying on its  business,  or takes any action to liquidate
                  its  assets;  if the  Defaulting  Party  files  a  voluntary
                  petition in bankruptcy or for arrangement, reorganization or
                  other relief under any bankruptcy legislation or any similar
                  law, now or hereafter in effect; or files an answer or other
                  pleading in any proceeding admitting insolvency,  bankruptcy
                  or  inability  to pay its  debts as they  mature;  or within
                  thirty (30) days after the filing


                                       18
<PAGE>
                  of  any   involuntary   proceedings   under  any  bankruptcy
                  legislation or similar law, now or hereafter in effect, such
                  proceedings  shall  not  have  been  vacated;  or  all  or a
                  substantial  part  of  its  assets  are  attached,   seized,
                  subjected to a writ or distress warrant, or are levied upon,
                  unless such attachment,  seizure,  writ,  warrant or levy is
                  vacated  within thirty (30) days, or shall be adjudicated as
                  bankrupt;  or shall make an  assignment  for the  benefit of
                  creditors or shall admit in writing its inability to pay its
                  debts  generally as they become due or shall  consent to the
                  appointment of a receiver or trustee or liquidator of all or
                  the  substantial   part  of  its  property;   or  any  order
                  appointing  a  receiver,   trustee  or   liquidator  of  the
                  Defaulting  Party  of  all  or a  substantial  part  of  its
                  property is not vacated within sixty (60) days following the
                  entry  thereof;  if an  order  shall  be made or  resolution
                  passed  for  the  winding-up  or  the   liquidation  of  the
                  Defaulting  Party or if the Defaulting Party adopts or takes
                  any   corporate   proceedings   for   its   dissolution   or
                  liquidation.

15.4     The  effective  date of  termination  will be the date  stated  in any
         termination notice given hereunder,  which date will not be before the
         expiration  of  any  applicable  cure  period  provided  for  in  this
         Agreement.

15.5     Termination   of  this  Agreement  will  not  affect  the  rights  and
         obligations  of the  Parties  accrued  under this  Agreement  prior to
         termination  nor the provisions  contained in this Agreement  which by
         their purpose have a term beyond the termination of this Agreement.

15.6     Upon the termination of this Agreement:
         i)       DSM   Biologics   shall   return  to  CYTOGEN  or   destroy,
                  immediately  upon  CYTOGEN's  first  request,  any  and  all
                  CYTOGEN  Proprietary  Information which is in DSM Biologics'
                  possession  and  all  documents   containing   such  CYTOGEN
                  Proprietary  Information or any part thereof, and all copies
                  and  extracts  made  thereof,   provided  however  that  DSM
                  Biologics  may keep one (1) copy of all CYTOGEN  Proprietary
                  Information  received by it for its legal files to enable it
                  to determine its  obligations  hereunder and for  regulatory
                  compliance;
         ii)      CYTOGEN   shall   return  to  DSM   Biologics   or  destroy,
                  immediately upon DSM Biologics'  first request,  any and all
                  DSM Biologics  Technology  which is in CYTOGEN's  possession
                  and all documents  containing such DSM Biologics  Technology
                  or any  part  thereof,  and all  copies  and  extracts  made
                  thereof, provided however that CYTOGEN may keep one (1) copy
                  of all DSM Biologics Technology received by it for its legal
                  files to enable it to determine  its  obligations  hereunder
                  and for regulatory compliance;


                                       19
<PAGE>

         iii)     DSM Biologics shall at CYTOGEN's  request and expense,  ship
                  to  CYTOGEN  any  capital   investment   and  raw  materials
                  purchased in the course of and for the Project;
         iv)      unless DSM  Biologics  shall have  terminated  the Agreement
                  pursuant to Section 15.3, DSM Biologics shall assist CYTOGEN
                  in transferring the Process to such facility as indicated by
                  CYTOGEN. Any costs therefor shall be borne by CYTOGEN.

SECTION 16 - NOTICES
--------------------

All notices, requests, demands and other communications hereunder shall be given
in  writing  and  shall be given by  prepaid  registered  mail,  receipt  return
requested, or by telecopier, to the other Party at the following addresses:

if to CYTOGEN:    Cytogen Corporation
                           600 College Road East
                           Princeton, New Jersey 08540-5308
                           United States of America

                           FaxTelecopier: 1-609-7508122
                           Attention: Mr. M. Titus
                           with a copy to: General Counsel

if to DSM Biologics:       DSM Biologics Company B.V.
                           72/2 Zuiderweg
                           9744 Groningen
                           The Netherlands

                           FaxTelecopier: 31-50-5222333
                           Attention: CEO
                           with a copy to: Legal Counsel

or at such other address as a Party may have  previously  indicated to the other
Party in writing in conformity  with the  foregoing.  Any such notice,  request,
demand or other  communication  shall be deemed  to have  been  received  on the
seventh  (7th)  business  day  following  the  date  of its  mailing  if sent by
registered  mail,  or the next  business day  immediately  following the date of
transmission if sent by telecopier.

SECTION 17 - ASSIGNMENT
-----------------------

This Agreement will be to the benefit of the permitted  successors and assign of
the Parties  hereto.  Neither  Party will be entitled to assign its rights under
this Agreement to any


                                       20
<PAGE>
individual, partnership or other entity, including Affiliates, without the prior
written consent of the other Party hereto and any attempted  assignments without
such  written  consent  shall be of no effect.  Notwithstanding  the  foregoing,
either Party shall be entitled,  without the prior written  consent of the other
Party,  to assign all or part of its rights under this  Agreement to a purchaser
of all or substantially all of its assets, or an entity with which it may merge,
provided  that  the  assignee  agrees  in  writing  to  assume  all  obligations
undertaken by its assignor in this  Agreement.  No assignment  shall relieve the
assigning Party of responsibility  for the performance of any of its obligations
hereunder.

SECTION 18 - DISPUTES AND APPLICABLE LAW
----------------------------------------

18.1     In the  event of a dispute  between  the  Parties,  the  Parties  shall
         firstly  make  every  effort  to find an  amicable  settlement  to such
         dispute.  Before having recourse to litigation  under Section 18.2, the
         Chief  Executive  Officers of the  Parties,  or their  nominees,  shall
         within one (1) month  (which time may be extended by mutual  agreement)
         from a request  by either  Party  meet and use their  best  efforts  to
         resolve any  disputes.  Failing  such  settlement,  the  provisions  of
         Section 18.2 shall apply.

18.2     All disputes which cannot be settled  amicably shall be finally settled
         by binding  arbitration under the rules of conciliation and arbitration
         of the International Chamber of Commerce.

18.3     This Agreement is governed by and  interpreted  in accordance  with the
         laws of England without regard to conflicts of laws principles.

SECTION 19 - FAILURE TO ACT
---------------------------

Notwithstanding any other provision of this Agreement, whenever a Party is given
a time period pursuant to this Agreement in which to exercise an option, make an
election, give a notice or the like, failure to act during such time period will
be conclusively deemed a decision not to exercise the option, make the election,
give the notice or the like, as fully as if the Party with the option, election,
right to give notice or the like had provided  written  notice of a decision not
to exercise the option, make the election, give the notice or the like.

SECTION 20 - FORCE MAJEURE
--------------------------

20.1     The obligations of either Party hereunder shall be suspended during the
         time and


                                       21
<PAGE>
         circumstance  beyond the control and without the fault or negligence of
         that Party so affected ("Force  Majeure")  including but not limited to
         inevitable  accidents,  perils of  navigation,  floods,  fire,  storms,
         epidemics,  acts of god, earthquakes,  explosions,  hostilities,  civil
         commotion,   war  (declared  or  undeclared),   orders,   requisitions,
         regulations  or  acts  of any  government  or  governmental  authority,
         whether de jure or de facto or any official purporting to act under the
         authority of any such government,  illegality  arising from domestic or
         foreign  laws or  regulations,  insurrections,  failure or  slowdown of
         public utilities or common carriers, inability to procure raw materials
         or other circumstances or conditions of a similar nature, quarantine or
         custom  restrictions,  damage  in  factories  or  warehouses,  strikes,
         lockouts or any other labor  difficulty at the Parties and/or suppliers
         of  goods,  raw  materials  and/or  excipients,   lack  of  conveyance,
         resulting in hindrance of this Agreement.

20.2     As soon as possible after being affected by a Force Majeure,  the Party
         so affected  shall  furnish to the other Party all  particulars  of the
         Force  Majeure  and the  manner in which  its  performance  is  thereby
         prevented or delayed.  The Party whose obligations  hereunder have been
         suspended shall promptly and diligently  pursue  appropriate  action to
         enable it to perform such  obligations,  except that the Parties  shall
         not  be  obligated  to  settle  any  strike,  lockout  or  other  labor
         difficulty on terms contrary to their wishes.

20.3     In the event that any Force  Majeure  cannot be  removed,  overcome  or
         abated  within  six (6) months  (or such  other  period as the  Parties
         jointly shall  determine) from the date the Party affected first became
         affected,  then either Party may, at the  expiration  of such period by
         notice to the other Party terminate this Agreement.

SECITION 21 - MISCELLANEOUS PROVISIONS
--------------------------------------

21.1     DSM  Biologics  shall  obtain all  permits  and  governmental  licenses
         required in connection  with its  activities  under this  Agreement and
         shall,  in  addition,  comply with  applicable  law in  performing  its
         obligations hereunder.

21.2     All  rights  and  recourses  of  a  Parts,  under  this  Agreement  are
         cumulative  and  the  exercise  by a  Party  of any of  its  rights  or
         recourses  will not  prevent  it from  exercising  any  other  right or
         recourse  available  under this Agreement or at law. All obligations of
         the Parties under this Agreement are indivisible.

21.3     If any covenant, obligation or term hereunder or the application of any
         part of this Agreement to any person,  party or circumstance  shall, to
         any  extent,  be  invalid  or  unenforceable,  the  remainder  of  this
         Agreement  or  the  application  of  such   covenants,   agreements  or
         obligations other than those which are held to be


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<PAGE>
         invalid  or  unenforceable  shall  not be  affected  thereby  and  each
         covenant, obligation and agreement contained herein shall be separately
         valid and enforceable to the full extent permitted by law.

21.4     This is an  agreement  between  separate  entities  and  neither is the
         agent,  representative,  master or servant of or possesses the power to
         obligate  the other or to make any  warranties  or  representations  on
         behalf of the other.  Nothing in this  Agreement will be interpreted so
         as to  create a  relationship  of  partners'  joint  ventures,  agents,
         mandate,  fiduciaries  or any other  similar  relationship  between the
         Parties.

21.5     Failure  by either  Party to take  action  against  the other  will not
         affect its right to require full  performance  of this Agreement at any
         time  thereafter.  The waiver by either Party of the breach of any term
         of this Agreement by the other Party will not operate or be interpreted
         as a waiver of any  subsequent  breach by such  Party.  No term of this
         Agreement  will be deemed to have been  waived by either  Party  unless
         such waiver is in writing.

21.6     This Agreement and the documents  referred to in it or attached to this
         Agreement  constitute  the entire  agreement  between the Parties  with
         respect  to  the  subject   matter   hereof  and  supersede  all  prior
         discussions,  negotiations  and  agreements  with respect  thereto.  No
         amendment of, change to or variance from this Agreement will be binding
         on either Party unless in writing and signed by the Parties.

21.7     Each of the Parties agrees to perform such acts,  sign and deliver such
         other  agreements' cause such meetings to be held,  resolutions  passed
         and  by-laws  enacted,  exercise  their  vote and  influence  as may be
         necessary or  desirable  from time to time in order to give full effect
         to this Agreement.

21.8     This Agreement may be executed in two (2)  counterparts,  each of which
         shall be an original and all of which shall constitute together but one
         and the same document.

21.9     The headings and  subheadings  of the sections of this  Agreement  have
         been included solely for ease of reference and do not form part of this
         Agreement.

21.10    All words and  personal  pronouns  relating  thereto  shall be read and
         construed as the number and gender of the Party or Parties  referred to
         in each case require and the verb shall be  construed as agreeing  with
         the required word and/or pronoun.


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21.11    This  Agreement  will not be binding upon the Parties until it has been
         signed  below on  behalf  of each  Party,  in  which  event it shall be
         effective as of the date of signing.

IN WITNESS  WHEREOF,  the  Parties  have  signed on the date  first  hereinabove
mentioned.







DSM BIOLOGICS COMPANY B.V.         CYTOGEN CORPORATION



/s/ G.P. Algra                     /s/ J.W.R. den Toom
------------------                 -----------------------------
G.P. Algra                         J.W.R. den Toom
President & CEO                    Director Marketing, Sales and
                                   Strategic Development





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