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                                    EXHIBIT 10.3

                          AGREEMENT

          Agreement dated as of August 12, 1998 among Targon 
Corporation, a Delaware corporation ("Targon"), Cytogen 
Corporation, a Delaware corporation ("Cytogen"), Elan 
Corporation, plc, an Irish public limited company ("Elan"), and 
Elan International Services, Ltd., a Bermuda corporation and 
wholly-owned subsidiary of Elan ("EIS").


                           RECITALS:

          A.  Some or all of the parties hereto are parties to 
(1) a Securities Purchase Agreement dated as of September 26, 
1996 (the "Securities Purchase Agreement") between Cytogen and 
EIS and a Joint Development and Operating Agreement dated as of 
September 26, 1996 (the "Development Agreement"; together with 
the Securities Purchase Agreement and the other documents and 
instruments executed on or about September 26, 1996 in connection 
therewith, the "Targon Agreements") among Elan, EIS, Cytogen and 
Targon, relating to, among other things, the establishment, 
capitalization and operation of Targon, and (2) a Note Purchase 
Agreement dated as of July 17, 1997 (the "Note Purchase 
Agreement") between Cytogen and EIS and a Securities Purchase 
Agreement (the "Cytogen/Targon Morphelan Agreement"; together 
with the Note Purchase Agreement and the other documents and 
instruments executed on or about July 17, 1997 in connection 
therewith, the "Morphelan Agreements") between Targon and 
Cytogen.  Capitalized terms not defined herein have the meanings 
ascribed to them in the applicable Targon Agreements or Morphelan 
Agreements.  Attached hereto as Exhibits A-1  and A-2 are 
complete lists of the Targon Agreements and the Morphelan 
Agreements.

          B.  In connection with the establishment of Targon, 
Targon acquired certain intellectual property, including without 
limitation, the rights to the Cytogen Compounds and the ATS 
Compounds, from each of Cytogen and Elan (or their respective 
affiliates), and in connection with the business of Targon, 
Targon undertook certain contractual and other relationships with 
various third parties.

          C.  On or about March 31, 1998, EIS exercised the 
Exchange Right, thereby becoming an equal stockholder with 
Cytogen in Targon.

          D.  The parties desire to set forth herein their 
agreements relating to the reorganization of the business of 
Targon and in connection therewith, the transfer of certain 
assets to Cytogen; the remaining business of Targon to be 
retained by Elan, subject to the other interests referred to 
below.  This Agreement is intended to be a binding agreement 
between the parties hereto. In connection with the transactions 
contemplated hereby, however, the parties may subsequently 
execute and deliver certain supplementary or definitive documents 
(the "Supplemental Agreements"); the Supplemental Agreements, if 
executed and delivered, shall supplement and/or supersede, as 
appropriate, the provisions hereof.


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                               AGREEMENT:

          The parties agree as follows:

          1.  Transfer of Certain Targon Products.  Targon hereby 
transfers, assigns and sets over to Cytogen all of Targon's 
right, title and interest in and to each of the Cytogen 
Compounds, together with any and all improvements, trade secrets 
and intellectual property developed or acquired by Targon since 
its date of inception and related thereto. In connection 
therewith, each of the parties agrees to the termination of 
Documents 1, 3, 4, 6 (as it relates to Cytogen's rights only), 7 
and 12 set forth on Exhibit A-1 hereto and that neither party 
shall have any further liability or obligation thereunder; it 
being understood that the other documents and instruments set 
forth on Exhibit A-1 shall remain in full force and effect as 
originally stated.  The parties agree that the consideration for 
the Cytogen Compounds and such related intellectual property and 
rights is $3 million.

          2.  Repayment of Certain Targon Obligations.  Within 
five business days of the date hereof, Targon shall pay to 
Cytogen by wire transfer $7,241,693; such amount, together with 
the consideration referred to in Section 1 above (i.e., an 
aggregate of $10,241,693, which includes accrued interest of 
$241,963) shall constitute payment and satisfaction in full of 
Targon's outstanding obligations under the Cytogen/Targon 
Morphelan Agreement and the accompanying promissory note and, 
accordingly, each of the parties agrees to the termination of 
Documents 3 and 4 set forth on Exhibit A-2 hereto and that 
subject to the payment of interest by Cytogen to EIS of $241,693 
within five business days of the date hereof neither party shall 
have any further liability or obligation thereunder; it being 
understood that Document 5 on Exhibit A-2 shall remain in full 
force and effect as originally stated.  The original promissory 
note shall, within five business days of the date hereof, be 
marked "paid in full" by Cytogen and returned to Targon.

          3.  Targon Share Purchase; Etc.  (a)  Cytogen hereby 
transfers, assigns and sets over to EIS all of Cytogen's right, 
title and interest in and to the 500,000 shares of Common Stock, 
par value $.01 per share, of Targon issued to Cytogen on 
September 26, 1996 (the "Targon Common Stock").  Cytogen 
represents that (i) it owns the Targon Common Stock free and 
clear, and not subject to any right, encumbrance, lien or 
restriction of any third party (collectively, "Encumbrances"), 
(ii) the transactions contemplated by this Agreement will vest in 
EIS legal and valid title to such Targon Common Stock, not 
subject to any Encumbrance and (iii) to its best knowledge, there 
are no other equity owners of Targon (or persons entitled to any 
rights, options or warrants therein, other than as previously 
disclosed to EIS).  The parties agree that the consideration for 
such transfer of Targon Common Stock is $10 million, which shall 
be paid by the parties hereby agreeing to terminate the Note 
Purchase Agreement and accompanying promissory note and, 
accordingly, each of the parties agrees to the termination of 
Documents 1 and 2 set forth on Exhibit A-2 hereto and that 
neither party shall have any further liability or obligation 
thereunder.  The original promissory note shall, within five 

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business days of the date hereof, be marked "paid in full" by EIS 
and returned to Cytogen . 

          (b)  Cytogen agrees that from and after the date 
hereof, it fully releases and it shall have no interest or right 
in and to Targon, its name or goodwill or any of Targon's 
intellectual property, all of which shall be owned by EIS and 
certain unaffiliated stockholders and/or option holders.

          4.  Payment of Certain Fees.  In connection with the 
reorganization of Targon and the termination of certain of the 
agreements referred to herein, Cytogen shall pay to EIS, within 
five business days of the date hereof, by wire transfer, a fee of 
$5 million.

          5.  Certain Investment in Cytogen.  EIS shall, subject 
to the remaining provisions of this Section 5, purchase from 
Cytogen, and Cytogen shall issue to EIS, a convertible, 
subordinated note in the original principal amount of $2 million 
(the "Convertible Note").  The Convertible Note shall be 
purchased at 100% of its original principal amount.  The terms of 
the Convertible Note shall be negotiated in good faith by each of 
Cytogen and EIS, who shall use their commercially reasonable 
efforts to conclude such negotiation and execution and fund the 
Convertible Note as soon as practicable, but in any event within 
15 days of the date hereof.  The Convertible Note shall (a) bear 
interest at 7% per year and be compounded semi-annually, however, 
such interest shall not be payable in cash but shall be added to 
principal for the first 24 months; thereafter, interest shall be 
payable in cash, (b) be subordinated to senior indebtedness of 
Cytogen and its subsidiaries on customary market terms, (c) be 
convertible into shares of Cytogen common stock, par value $.01 
per share (the "Cytogen Common Stock"), at a conversion price of 
$2.80 per share, which shall be subject to customary 
anti-dilution provisions, (d) have a term of seven years and (e) 
contain customary financial and operating covenants for similar 
instruments issued by similarly-situated issuers.

          6.  Certain Representations. (a)  Cytogen represents to 
Elan the following: (i) Cytogen is duly and validly existing in 
good standing in the state of Delaware and each other 
jurisdiction in which the conduct of its business requires such 
qualification; (ii) Cytogen has full corporate authority to 
execute and deliver this Agreement and the Supplemental 
Agreements and to consummate the transactions contemplated hereby 
and thereby, and this Agreement has been duly executed and 
delivered and constitutes the legal and valid obligation of 
Cytogen and is enforceable against Cytogen in accordance with its 
terms; (iii) the Convertible Note and the shares of Cytogen 
Common Stock issuable upon conversion thereof, have been or will 
be duly and validly authorized and when issued will be fully paid 
and non assessable and free from any and all options, warrants 
and preemptive and other rights; (iv) Cytogen is not in default 
in any material respect of its charter or by laws, any applicable 
laws or regulations or any contract or agreement binding upon or 
affecting it or its properties or assets and the execution, 
delivery and performance of this Agreement and the transactions 
contemplated hereby will not result in any such violation; (v) 
after due inquiry, Cytogen is not aware of any liability or 
obligation of Targon, for indebtedness, in respect of employee or 
development or other matters or otherwise, other than as 
previously disclosed in writing to EIS; and (vi) Cytogen has not 
retained any broker or finder in connection with the transactions 

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contemplated hereby and no person or entity is entitled to any 
fee, commission or other compensation in respect thereof.

          (b)  Elan and EIS, jointly and severally, represent to 
Cytogen the following: (i) each of Elan and EIS is duly and 
validly existing in good standing in the jurisdiction of its 
incorporation and each other jurisdiction in which the conduct of 
its business requires such qualification; (ii) each of Elan and 
EIS has full corporate authority to execute and deliver this 
Agreement and the Supplemental Agreements and to consummate the 
transactions contemplated hereby and thereby; this Agreement has 
been duly executed and delivered and constitutes the legal and 
valid obligations of each of Elan and EIS and is enforceable 
against them in accordance with its terms; (iii) neither Elan nor 
EIS is in default in any material respect of its memorandum and 
articles of association, any applicable laws or regulations or 
any contract or agreement binding upon or affecting it or its 
properties or assets and the execution, delivery and performance 
of this Agreement and the transactions contemplated hereby will 
not result in any such violation and (iv) neither Elan nor EIS 
has retained any broker or finder in connection with the 
transactions contemplated hereby and no person or entity is 
entitled to any fee, commission or other compensation in respect 
thereof.

          (c) Neither Elan nor EIS has entered into on behalf of 
Targon, as of the date hereof, any commercial transactions 
relating to the licensing of the intellectual property relating 
to Morphelan (as defined in the Morphelan Agreements) or 
marketing of Morphelan.  In addition, neither Elan nor EIS is, as 
of the date hereof, in substantive discussion with any third 
party relating to the licensing of the intellectual property 
relating to Morphelan or marketing of Morphelan.   For greater 
clarity EIS, Elan and/or Targon may continue and consummate any 
discussions or negotiations currently underway in connection with 
such intellectual property or products without breaching this 
representation.

          7.  Certain Indemnifications.  (a)  Each of Cytogen and 
EIS (in such capacity, an "Indemnitor") hereby indemnifies and 
holds the other and the other's affiliates and their respective 
directors, officers and employees (collectively, the 
"Indemnitees") harmless from and against any and all loss, cost 
or expense, including without limitation, reasonable attorneys' 
fees and disbursements (collectively, "Losses"), incurred by an 
Indemnitee as a result of any breach or default of any of the 
representations or covenants contained in this Agreement by such 
Indemnitor or its affiliates.  

          (b)  In addition to the indemnification provided for in 
Section 7(a) above, EIS hereby indemnifies and holds harmless 
Cytogen and Cytogen's other Indemnitees from and against any 
Losses resulting from the business or operations of Targon from 
and after the date hereof, except to the extent that any such 
Loss was caused or resulted from any wrongful or improper action 
taken by or on behalf of Cytogen or its affiliates.

          (c)  An Indemnitor (including EIS under Section 7(b) 
above) shall have the right to direct any proceeding relating to 
third-party claim resulting in any indemnity claim hereunder and 
no Indemnitee shall settle any matter that could result in 
indemnification hereunder without the consent of the Indemnitor, 
which consent shall not be unreasonably withheld.  Each of the 

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parties shall reasonably cooperate with the other in connection 
with any third-party claim that could potentially result in 
indemnification hereunder.

          8.  Confidentiality, Non disclosure, Etc.  (a) Each of 
the parties shall keep and maintain this Agreement and the 
Supplemental Agreements and the transactions contemplated hereby 
and thereby confidential and not disclose such matters or the 
participation of the parties in such transactions to any person 
or entity, except (a) to the extent required by applicable law or 
administrative or judicial process or (b) for a press release as 
may be required by applicable laws, so long as the text thereof 
shall have been provided to the other party at least one business 
day prior to issuance thereof and such other party shall have 
been given the opportunity to approved the text thereof, which 
approval shall not be unreasonably withheld.

 		       (b)  In addition to the obligations set forth in 
Section 8(a) above, Cytogen agrees that it shall, and it shall 
cause its officers, directors, employees and agents, to keep and 
maintain in confidence and not disclose to any other person or 
entity any and all confidential or proprietary information 
relating to Targon or the business and affairs of Targon 
disclosed to or in the possession of such persons; provided, that 
the foregoing shall not apply to the extent required by 
applicable law or administrative or judicial process.  
Confidential or proprietary information relating to Targon shall 
include all information relating to the business or affairs of 
Targon derived or relating to any periods ending on or prior to 
the date hereof.

          9.  Further Assurances.  Each of the parties hereto 
acknowledges that the transactions contemplated by this Agreement 
may require additional actions to be taken or additional 
documents or instruments to be executed, delivered or filed.  
Each of such parties agrees, at its own expense and without 
charge to the others, promptly to take such actions and to 
execute such documents and instruments that may be reasonably 
requested by the other or appropriate in the context of such 
transactions.

          10.  Notices.  Notices shall be in writing, given by 
facsimile transmission (along with confirming originals), 
reputable overnight courier (such as Federal Express) or by hand 
and shall be given to the parties at their respective addresses 
as set forth in the Securities Purchase Agreement.

          11.  Miscellaneous.  This Agreement (a) shall be 
governed by and construed in accordance with the internal laws of 
the State of New York, without regard to principles of conflicts 
of laws and, in connection therewith, each party consents to the 
non exclusive jurisdiction of any federal or state court sitting 
in the County, City and State of New York over any dispute 
arising from this letter agreement; (b) shall not be assigned or 
delegated by either party without the consent of the other (other 
than to their respective affiliates) and, subject to the 
foregoing provisions of this clause (b), shall be binding upon 
the parties' respective successors and assigns; (c) may be 
executed in counterparts and delivered by facsimile transmission; 
and (d) together with the Supplemental Agreements, constitutes 
the entire agreement among the parties and supersedes all prior 
agreements or understandings among the parties.
 
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          IN WITNESS WHEREOF, the parties have executed this 
Agreement as of the date first set forth above.

                                        Targon Corporation



                                        By:  /s/ Michael Sember  
                                            ------------------------
                                            Name:  Michael Sember
                                            Title: Chairman and CEO

                                        Cytogen Corporation



                                        By:  /s/ John E. Bagalay, Jr.
                                            -------------------------
                                            Name:  John E. Bagalay, Jr.	
                                            Title: President and 
                                                   Chief Executive Officer

                                        Elan Corporation, plc



                                        By:  /s/ Thomas G. Lynch     
                                           ---------------------------
                                           Name:  Thomas G. Lynch
                                           Title: Director

                                        Elan International Services, Ltd.



                                        By:  /s/ Kevin Insley 
                                           ----------------------------
                                           Name:  Kevin Insley
                                           Title: President
 


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                               Exhibit A-1
[All documents are dated September 26, 1996 unless otherwise indicated]

1.  Securities Purchase Agreement between Cytogen and EIS

2.  Cytogen Certificate of Designations, Powers, Preferences and 
Rights of Series A Preferred Stock

3.  Stock Subscription Agreement between Cytogen and Targon

4.  Warrant for 1,000,000 shares of Cytogen Common Stock issued 
by Cytogen to EIS

5.  Registration Rights Agreement between Cytogen and EIS

6.  Registration Rights Agreement between Targon, on the one 
hand, and EIS and Cytogen, on the other hand

7.  Joint Development and Operating Agreement among Elan, Cytogen 
and Targon

8.  Technology Transfer Agreement between ATS and Targon

9.  Letter from Elan to Targon relating to Elan's necessary steps 
in connection with the transfer of the ATS Compounds

10.  Technology Assignment Agreement between Elan Pharmaceutical 
Research Corp. ("EPRC") and Targon

11.  Letter from EPRC to Elan relating to the ATS Compounds

12.  Technology Transfer Agreement between Cytogen and Targon

 

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                            Exhibit A-2
[All documents are dated July 17, 1997 unless otherwise indicated]

1.  Note Purchase Agreement between Cytogen and EIS

2.  Promissory note from Cytogen to EIS

3.  Securities Purchase Agreement between Targon and Cytogen

4.  Promissory Note from Targon to Cytogen

5.  License Agreement from Elan to Targon


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