As filed with the Securities and Exchange Commission on November 5, 2004
                         Registration Statement No. 333-

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON, DC 20549
                       -----------------------------------
                                    FORM S-3
                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933

                               CYTOGEN CORPORATION
         ---------------------------------------------------------------
             (Exact Name of Registrant as Specified in Its Charter)

           Delaware                                         22-2322400
---------------------------------                  -----------------------------
  (State or Other Jurisdiction                          (I.R.S. Employer
of Incorporation or Organization)                     Identification Number)

                        650 College Road East, 3rd Floor
                           Princeton, New Jersey 08540
                                 (609) 750-8200
          -------------------------------------------------------------
          (Address, Including Zip Code, and Telephone Number, Including
             Area Code, of Registrant's Principal Executive Offices)

                             William J. Thomas, Esq.
                    Senior Vice President and General Counsel
                               Cytogen Corporation
                        650 College Road East, 3rd Floor
                           Princeton, New Jersey 08540
                                 (609) 750-8223
            --------------------------------------------------------
            (Name, Address, Including Zip Code, and Telephone Number,
                   Including Area Code, of Agent for Service)
                     -------------------------------------
                                    COPY TO:
                            Randall B. Sunberg, Esq.
                           Morgan, Lewis & Bockius LLP
                               502 Carnegie Center
                           Princeton, New Jersey 08540
                                 (609) 919-6600
                     -------------------------------------

APPROXIMATE  DATE  OF  COMMENCEMENT  OF  PROPOSED  SALE  TO  PUBLIC:  As soon as
practicable after this Registration Statement becomes effective.

     If the only  securities  being  registered  on this form are being  offered
pursuant to dividend or interest  reinvestment plans, please check the following
box. [ ]
     If any of the securities being registered on this form are to be offered on
a delayed or continuous  basis  pursuant to Rule 415 under the Securities Act of
1933, other than securities offered only in connection with dividend or interest
reinvestment plans, check the following box. [x]
     If this form is filed to  register  additional  securities  for an offering
pursuant to Rule 462(b) under the Securities Act, please check the following box
and list  the  Securities  Act  registration  statement  number  of the  earlier
effective registration statement for the same offering. [ ]       .
                                                           -------
     If this form is a  post-effective  amendment  filed pursuant to Rule 462(c)
under the  Securities  Act,  check the following box and list the Securities Act
registration  statement number of the earlier effective  registration  statement
for the same offering. [ ]      .
                          ------
     If delivery of the  prospectus is expected to be made pursuant to Rule 434,
please check the following box. [ ]

                          ---------------------------




                         CALCULATION OF REGISTRATION FEE



                                                                          Proposed Maximum
    Title Of Each Class of Securities           Amount to be             Aggregate Offering              Amount Of
            To Be Registered                     Registered                    Price                 Registration Fee
-------------------------------------------------------------------------------------------------------------------------
                                                                                                 
Debt Securities..........................            ---                        ---                       ---

Common stock,
   $0.01 par value per share(1)..........            ---                        ---                       ---

Preferred Stock,
   $0.01 par value per share.............            ---                        ---                       ---

Warrants.................................            ---                        ---                       ---

Units....................................            ---                        ---                       ---

Total(4).................................       $70,000,000(2)            $70,000,000(2)(3)             $8,869


(1)  Includes  rights to  purchase  shares of our Series C Junior  Participating
     Preferred Stock pursuant to the Amended and Restated Rights Agreement dated
     October 19, 1998. No separate  consideration  is paid for these rights and,
     as a result,  the  registration fee for these rights is included in the fee
     for the common stock.

(2)  The securities registered consist of $70,000,000 of an indeterminate number
     or amount of debt  securities,  common  stock,  preferred  stock,  warrants
     and/or units, as may be issued from time to time at  indeterminate  prices.
     In no event will the aggregate  initial  offering  price of all  securities
     issued from time to time  pursuant to this  registration  statement  exceed
     $70,000,000  or the  equivalent  thereof  in  foreign  currencies,  foreign
     currency units or composite  currencies.  Such amount  represents the issue
     price rather than the  principal  amount of any debt  securities  issued at
     original  issue  discount or  liquidation  value of any shares of preferred
     stock.

(3)  Estimated  solely  for the  purpose of  calculating  the  registration  fee
     pursuant  to Rule 457(o) of the  Securities  Act of 1933,  as amended  (the
     "Securities  Act").  Exclusive  of  accrued  interest,   distributions  and
     dividends,  if  any.  Rule  457(o)  permits  the  registration  fee  to  be
     calculated  on  the  basis  of the  maximum  offering  price  of all of the
     securities listed and, therefore,  the table does not specify by each class
     information  as to the  amount to be  registered  or the  proposed  maximum
     offering price per security.

(4)  This registration  statement also registers such  indeterminate  amounts of
     securities as may be issued from time to time upon conversion,  exercise or
     settlement of, or in exchange for, the securities registered hereunder and,
     pursuant to Rule 416(a) under the Securities Act of 1933, as amended,  such
     indeterminable  number of  shares  as may be issued  from time to time as a
     result of anti-dilution  provisions  thereof or upon conversion or exchange
     as a result of stock splits, stock dividends or similar transactions.

                         ------------------------------

THE COMPANY HEREBY AMENDS THIS  REGISTRATION  STATEMENT ON SUCH DATE OR DATES AS
MAY BE  NECESSARY  TO DELAY ITS  EFFECTIVE  DATE UNTIL THE COMPANY  SHALL FILE A
FURTHER AMENDMENT WHICH  SPECIFICALLY  STATES THAT THIS  REGISTRATION  STATEMENT
SHALL  THEREAFTER  BECOME  EFFECTIVE  IN  ACCORDANCE  WITH  SECTION  8(A) OF THE
SECURITIES  ACT OF  1933  OR  UNTIL  THE  REGISTRATION  STATEMENT  SHALL  BECOME
EFFECTIVE ON SUCH DATE AS THE COMMISSION,  ACTING PURSUANT TO SAID SECTION 8(A),
MAY DETERMINE.




THE  INFORMATION IN THIS  PROSPECTUS IS NOT COMPLETE AND MAY BE CHANGED.  WE MAY
NOT SELL  THESE  SECURITIES  UNTIL THE  REGISTRATION  STATEMENT  FILED  WITH THE
SECURITIES AND EXCHANGE COMMISSION IS EFFECTIVE. THIS PROSPECTUS IS NOT AN OFFER
TO SELL THESE SECURITIES AND IT IS NOT SOLICITING OFFERS TO BUY THESE SECURITIES
IN ANY STATE OR JURISDICTION WHERE THE OFFER OR SALE IS NOT PERMITTED.

                  SUBJECT TO COMPLETION, DATED NOVEMBER 5, 2004

PROSPECTUS

                               CYTOGEN CORPORATION

                                   $70,000,000

                                 DEBT SECURITIES
                                  COMMON STOCK
                                 PREFERRED STOCK
                                    WARRANTS
                                      UNITS


     Cytogen Corporation may offer up to $70,000,000 of debt securities,  common
stock,  preferred stock,  warrants and units, from time to time. This prospectus
describes the general  terms of, and the general  manner in which we will offer,
these securities.  When we offer these securities,  we will provide a prospectus
supplement  containing  the  specific  terms of that  offering.  The  prospectus
supplement  will also  describe  the  specific  manner  in which we offer  these
securities.  This  prospectus  may not be  used to  consummate  sales  of  these
securities unless accompanied by a prospectus supplement.

     Our common stock is traded on the Nasdaq  National  Market under the symbol
"CYTO." On  November  3, 2004,  the  closing  sale price of our common  stock on
Nasdaq was $10.26 per share.  You are urged to obtain current market  quotations
for our common stock.


                         ------------------------------

     INVESTING  IN OUR  SECURITIES  INVOLVES  A HIGH  DEGREE OF RISK.  SEE "RISK
FACTORS" COMMENCING ON PAGE 4.

                         ------------------------------

         NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY STATE SECURITIES
COMMISSION HAS APPROVED OR DISAPPROVED OF THESE SECURITIES OR DETERMINED IF THIS
PROSPECTUS  IS TRUTHFUL OR  COMPLETE.  ANY  REPRESENTATION  TO THE CONTRARY IS A
CRIMINAL OFFENSE.

                The date of this prospectus is November   , 2004.
                                                       ---




                                TABLE OF CONTENTS

--------------------------------------------------------------------------------
  About this Prospectus.................................................    2
  Cytogen Corporation...................................................    3
  Reverse Stock Split...................................................    3
  Risk Factors..........................................................    4
       We have a history of operating losses and an accumulated deficit
         and expect to incur losses in the future.......................    4
       We depend on sales of ProstaScint and Quadramet for substantially
         all of our near-term revenues..................................    4
       We depend on acceptance of our products by the medical community
         for the continuation of our revenues...........................    5
       We rely heavily on our collaborative partners....................    5
       Our business could be harmed if certain agreements expire or are
         terminated.....................................................    6
       Our intellectual property is difficult to protect................    7
       There are risks associated with the manufacture and supply of
         our products...................................................    9
       Our products, generally, are in the early stages of development
         and commercialization and we may never achieve the revenue
         goals set forth in our business plan...........................   10
       All of our potential oncology products will be subject to the
         risks of failure inherent in the development of diagnostic
         or therapeutic products based on new technologies..............   11
       Competition in our field is intense and likely to increase.......   11
       We have limited sales, marketing and distribution capabilities
         for our products...............................................   12
       Failure of third party payors to provide adequate coverage and
         reimbursement for our products could limit market acceptance
         and affect pricing of our products and affect our revenues.....   13
       If we are unable to comply with applicable governmental regulation
         we may not be able to continue our operations..................   14
       We depend on attracting and retaining key personnel..............   15
       Our business exposes us to product liability claims that may
         exceed our financial resources, including our insurance
         coverage, and may lead to the curtailment or termination of
         our operations.................................................   16
       Our security measures may not protect our unpatented proprietary
         technology.....................................................   16
       We may not be able to implement AxCell's business plan...........   16
       We may need to raise additional capital, which may not be
         available......................................................   16
       Our capital raising efforts may dilute stockholder interests.....   17
       We may need to raise funds other than through the issuance of
         equity securities..............................................   17
       Our PSMA product development program is novel and, consequently,
          inherently risky..............................................   17
       We could be negatively impacted by future interpretation or
         implementation of federal and state fraud and abuse laws,
         including anti-kickback laws and federal and state false claims
         statutes ......................................................   18
       Our business involves environmental risks that may result in
         liability......................................................   20
--------------------------------------------------------------------------------

                                      -i-



--------------------------------------------------------------------------------

       We have been subject to patent litigation........................   21
       Our stock price has been and may continue to be volatile, and
         your investment in our stock could decline in value or
         fluctuate significantly........................................   21
       We have adopted various anti-takeover provisions which may
         affect the market price of our common stock and prevent or
         frustrate attempts by our stockholders to replace or remove
         our management team............................................   21
       The liquidity of our common stock could be adversely affected if
         we are delisted from The Nasdaq National Market................   22
       A large number of our shares are eligible for future sale which
         may adversely impact the market price of our common stock......   23
       Because we do not intend to pay, and have not paid, any cash
         dividends on our shares of common stock, our stockholders will
         not be able to receive a return on their shares unless the
         value of our shares appreciates and they sell them.............   23
  Special Note Regarding Forward-Looking Statements.....................   23
  Use of Proceeds.......................................................   24
  Ratio of Earnings to Fixed Charges and Preferred Stock Dividends......   24
  Description of Debt Securities........................................   25
  Description of Capital Stock..........................................   31
  Description of Warrants...............................................   34
  Description of Units..................................................   36
  Global Securities.....................................................   36
  Plan of Distribution..................................................   38
  Legal Matters.........................................................   40
  Experts...............................................................   40
  Where You Can Find More Information...................................   41
  Information Incorporated By Reference.................................   41
--------------------------------------------------------------------------------

                                      -ii-



                              ABOUT THIS PROSPECTUS

     This prospectus is part of a registration  statement that we filed with the
Securities and Exchange  Commission  using a "shelf"  registration or continuous
offering process.  We may from time to time sell debt securities,  common stock,
preferred  stock,  warrants  and/or units in one or more offerings up to a total
dollar amount of $70,000,000.

     Each time we sell these  securities  we will  provide you with a prospectus
supplement  containing  specific  information about the terms of each such sale.
This prospectus may not be used to sell any of the securities unless accompanied
by a prospectus  supplement.  The prospectus  supplement also may add, update or
change information in this prospectus. If there is any inconsistency between the
information in the prospectus and the prospectus supplement,  you should rely on
the  information  in the  prospectus  supplement.  You  should  read  both  this
prospectus and any prospectus  supplement  together with additional  information
described under the heading "Where You Can Find More  Information"  beginning on
page 41 of this prospectus.

     Unless otherwise  indicated or unless the context otherwise  requires,  all
references in this prospectus to "we," "us," or similar  references mean Cytogen
Corporation and its subsidiaries.

     You should rely only on the information  contained in this prospectus or in
a prospectus  supplement or amendment.  We have not authorized anyone to provide
you with information  different from that contained or incorporated by reference
in this  prospectus.  We may  offer  to  sell,  and  seek  offers  to buy  these
securities  only in  jurisdictions  where  offers and sales are  permitted.  The
information contained in this prospectus or a prospectus supplement or amendment
or  incorporated  herein by  reference  is accurate  only as of the date of this
prospectus, regardless of the time of delivery of this prospectus or of any sale
of securities.

                                      -2-



                               CYTOGEN CORPORATION

     Cytogen  Corporation  is a  product-driven  biopharmaceutical  company that
develops  and  commercializes  innovative  molecules  that  can be used to build
leading  franchises  across  multiple  markets.  Our marketed  products  include
QuadrametTM (samarium Sm-153 lexidronam  injection),  a long-acting,  non-opioid
treatment  for the relief of pain due to  metastatic  bone disease  arising from
prostate, breast, multiple myeloma and other types of cancer, and ProstaScint(R)
(capromab   pendetide)  kit  for  the  preparation  of  Indium  In-111  capromab
pendetide,  the first and only commercial  monoclonal  antibody-based  molecular
imaging agent targeting  prostate-specific  membrane  antigen,  or PSMA, used to
image the extent and spread of prostate  cancer,  in the United  States.  We are
also  developing  therapeutics  targeting   prostate-specific  membrane  antigen
(PSMA),  a protein highly  expressed on the surface of prostate cancer cells and
the neovasculature of solid tumors.

     In addition to the products listed above, in August,  2000, we expanded our
product pipeline by entering into marketing,  license and supply agreements with
Advanced  Magnetics,  Inc. for  Combidex(R).  We have  exclusive  United  States
marketing rights to Combidex for all indications.  Combidex  (ferumoxtran-10) is
an   investigational   molecular   imaging   agent   consisting  of  iron  oxide
nanoparticles,  which is currently being  developed for use in conjunction  with
magnetic  resonance  imaging  to aid in the  differentiation  of  cancerous  and
non-cancerous  lymph nodes,  and is currently  under review by the U.S. Food and
Drug  Administration  (FDA). In September 2004,  Advanced Magnetics  submitted a
complete response to an approvable letter received in June 2000 from the FDA for
Combidex.  The complete response was accepted by the FDA and was assigned a user
fee goal date of March 30, 2005.

     We have had a history of operating losses since our inception. We had a net
loss of $5.6 million for the three months ended  September  30, 2004, a net loss
of $14.3 million for the nine months ended  September 30, 2004 and a net loss of
$9.4 million for the year ended December 31, 2003.  Although we continually look
to expand our product pipeline,  we currently rely on two products,  ProstaScint
and Quadramet, for substantially all of our revenues. In addition, we have, from
time to time, ceased sales of certain products,  such as brachytherapy  products
and OncoScint(R) CR/OV, that we previously  believed would generate  significant
revenues for our business.  Our products are subject to  significant  regulatory
review  by the  FDA  and  other  federal  and  state  agencies,  which  requires
significant time and expenditures in seeking product approvals.  In addition, we
rely on  collaborative  partners  to a  significant  degree to  manufacture  our
products,  to secure raw  materials,  and to provide  licensing  rights to their
proprietary products for us to sell and market to others.

     We are a Delaware corporation. We were incorporated and began operations in
1980 under the name Hybridex,  Inc. and changed our name to Cytogen  Corporation
in April 1980. Our executive offices are located at 650 College Road East, Suite
3100,  Princeton,  New Jersey 08540,  our telephone number is (609) 750-8200 and
our Internet address is  http://www.cytogen.com  The information on our Internet
website is not incorporated by reference in this prospectus.  Unless the context
otherwise  requires  references in this prospectus to "Cytogen,"  the "Company,"
"we," "us," and "our" refer to Cytogen Corporation and our subsidiaries.

     ProstaScint(R)  and OncoScint(R) are registered United States trademarks of
Cytogen  Corporation.  We are the owner of a  pending  United  States  trademark
application,  Serial No. 78374967, relating to Quadramet. All other trade names,
trademarks or service marks appearing in this Registration Statement on Form S-3
are the  property of their  respective  owners,  and not the property of Cytogen
Corporation or any of our subsidiaries.

                               REVERSE STOCK SPLIT

     On October 25, 2002, we received  approval from our  stockholders at a duly
called and held special meeting of stockholders to effect a reverse split of our
common stock. Our Board of Directors  thereafter  approved a one-for-ten reverse
split of our outstanding, issued and authorized shares of

                                      -3-



common stock,  which became effective on October 25, 2002. All numbers set forth
in  this  Registration  Statement  on  Form  S-3  reflect  the  effect  of  such
one-for-ten reverse stock split.

                                  RISK FACTORS

     INVESTING IN OUR COMMON STOCK OR OTHER SECURITIES INVOLVES A HIGH DEGREE OF
RISK. YOU SHOULD CAREFULLY CONSIDER THE RISKS AND UNCERTAINTIES  DESCRIBED BELOW
BEFORE PURCHASING OUR SECURITIES.  IF ANY OF THE FOLLOWING RISKS ACTUALLY OCCUR,
OUR BUSINESS,  FINANCIAL CONDITION OR RESULTS OF OPERATIONS WOULD LIKELY SUFFER.
IN THAT CASE,  THE TRADING  PRICE OF OUR COMMON  STOCK OR THE VALUE OF OUR OTHER
SECURITIES COULD FALL, AND YOU MAY LOSE ALL OR PART OF THE MONEY YOU PAID TO BUY
OUR SECURITIES.

WE HAVE A HISTORY OF OPERATING  LOSSES AND AN ACCUMULATED  DEFICIT AND EXPECT TO
INCUR LOSSES IN THE FUTURE.

     Given the high level of  expenditures  associated with our business and our
inability to generate revenues  sufficient to cover such  expenditures,  we have
had a history of operating losses since our inception. We had a net loss of $5.6
million for the three  months  ended  September  30,  2004,  a net loss of $14.3
million  for the nine  months  ended  September  30, 2004 and a net loss of $9.4
million for the year ended December 31, 2003. We had net losses of $15.7 million
and $12.1 million for the years ended December 31, 2002 and 2001,  respectively.
We had an accumulated deficit of $380 million as of September 30, 2004.

     In order to develop and commercialize  our  technologies,  particularly our
prostate-specific  membrane  antigen  technology,  and  expand our products,  we
expect to incur  significant  increases  in our  expenses  over the next several
years. As a result, we will need to generate  significant  additional revenue to
become profitable.

     To date,  we have  taken  affirmative  steps to  rationalize  our  trend of
operating losses. Such steps include, among other things:

  o  undergoing  steps to  realign and implement  our focus as a  product-driven
     biopharmaceutical company;

  o  establishing and maintaining our in-house specialty sales force;

  o  reacquiring North American and Latin American marketing rights to Quadramet
     from Berlex Laboratories in August 2003; and

  o  enhancing our marketed product portfolio  through  marketing  alliances and
     strategic  arrangements  such as we have  done with the  Combidex  product,
     which we intend to market if this product is approved by the FDA.

     Although we have taken  these  affirmative  steps,  we may never be able to
successfully implement them, and our ability to generate and sustain significant
additional  revenues  or achieve  profitability  will  depend  upon the  factors
discussed  elsewhere in this section  entitled,  "Risk Factors." As a result, we
may never be able to  generate  or  sustain  significant  additional  revenue or
achieve profitability.

WE DEPEND ON SALES OF  PROSTASCINT  AND QUADRAMET FOR  SUBSTANTIALLY  ALL OF OUR
NEAR-TERM REVENUES.

     We expect Quadramet and ProstaScint to account for substantially all of our
product  related  revenues in the near future.  Revenues  from  ProstaScint  and
Quadramet accounted for approximately 40% and 60%, respectively,  of our product
related  revenues in the three months ended September 30, 2004, and 50% and 50%,
respectively  in the nine months ended  September  30, 2004.  For the year ended

                                      -4-



December  31,  2003,  royalty  and product  revenues  from  Quadramet  and sales
revenues from ProstaScint accounted for approximately 35% and 60%, respectively,
of our product related revenues. For the year ended December 31, 2002, royalties
from Quadramet and product revenues from ProstaScint accounted for approximately
15% and 64%,  respectively,  of our product related revenues.  If ProstaScint or
Quadramet does not achieve broader market acceptance,  either because we fail to
effectively  market  such  products  or  our  competitors   introduce  competing
products,  we  may  not  be  able  to  generate  sufficient  revenue  to  become
profitable.

WE DEPEND  ON  ACCEPTANCE  OF OUR  PRODUCTS  BY THE  MEDICAL  COMMUNITY  FOR THE
CONTINUATION OF OUR REVENUES.

     Our business,  financial  condition and results of operations depend on the
acceptance  of our  marketed  products  as safe,  effective  and  cost-efficient
alternatives  to other  available  treatment  and  diagnostic  protocols  by the
medical community, including:

  o  health care providers, such as hospitals and physicians; and

  o  third-party  payors,  including  Medicare,   Medicaid,   private  insurance
     carriers and health maintenance organizations.

     With respect to ProstaScint,  our customers,  including  technologists  and
physicians,  must successfully  complete our Partners in Excellence  Program,  a
proprietary  training  program  designed to promote the correct  acquisition and
interpretation of ProstaScint  images. This product is  technique-dependent  and
requires  a  learning  commitment  by  technologists  and  physicians  and their
acceptance of this product as part of their treatment practices. With respect to
Quadramet,  we believe that  challenges we may  encounter in  generating  market
acceptance  for this product  include the need to further  educate  patients and
physicians about Quadramet's properties,  approved uses and how Quadramet may be
differentiated  from other  radiopharmaceuticals  and used in  combination  with
other treatments for the palliation of pain due to metastatic bone disease, such
as analgesics, opioids, bisphosphonates, and chemotherapeutics. If we are unable
to educate our existing and future  customers  about  ProstaScint and Quadramet,
our revenues may decrease.  If ProstaScint  or Quadramet do not achieve  broader
market acceptance,  we may not be able to generate  sufficient revenue to become
profitable.

     Generating   market  acceptance  and  sales  of  our  products  has  proven
difficult, time consuming and uncertain. We launched OncoScint CR/OV in December
1992,  ProstaScint  in October  1996,  Quadramet in March 1997, a  brachytherapy
product in February 2001 and NMP22  BladderChek in November  2002.  Revenues for
ProstaScint  grew from $55,000 in 1996 to $6.5 million in 2003.  Royalties  from
sales and product  revenues for Quadramet grew from $3.3 million in 1997 to $3.9
million in 2003. Royalties from sales of Quadramet in the initial years of sales
were supported by a guaranteed minimum revenue  arrangement with the third party
licensor of Quadramet.  OncoScint  CR/OV selling  activity was  discontinued  in
December  2002  and  selling  activities  for the  brachytherapy  products  were
discontinued in January 2003. We began  marketing NMP22  BladderChek in November
2002. Sales of NMP22  BladderChek have been minimal to date and we do not expect
significant revenues from sales of NMP22 BladderChek.  Currently,  substantially
all of our revenues are derived from sales of ProstaScint and Quadramet.

WE RELY HEAVILY ON OUR COLLABORATIVE PARTNERS.

     Our success depends largely upon the success and financial stability of our
collaborative  partners.  We have entered into the following  agreements for the
development,  sale,  marketing,  distribution  and  manufacture of our products,
product candidates and technologies:

  o  a license agreement with The Dow Chemical Company relating to the Quadramet
     technology;

                                      -5-



  o  a manufacturing  and supply agreement for the manufacture of Quadramet with
     Bristol-Myers Squibb Medical Imaging, Inc.;

  o  a manufacturing  agreement for the manufacture of ProstaScint with Laureate
     Pharma, L.P.;

  o  marketing,  license and supply  agreements  with Advanced  Magnetics,  Inc.
     related to Combidex;

  o  a distribution  services agreement with Specialty  Pharmaceutical  Services
     for ProstaScint;

  o  various  agreements which form and control our joint venture with Progenics
     Pharmaceuticals, Inc. for the development of PSMA for in vivo immunotherapy
     for prostate and other cancers; and

  o  a license  agreement between our joint venture and AlphaVax Human Vaccines,
     Inc.

     Because   our   collaborative   partners   are   responsible   for  certain
manufacturing and distribution  activities,  among others,  these activities are
outside  our  direct  control  and we  rely on our  partners  to  perform  their
obligations.  In the event that our collaborative partners are entitled to enter
into third party  arrangements that may economically  disadvantage us, or do not
perform their obligations as expected under our agreements, our products may not
be  commercially  successful.  As a result,  any  success may be delayed and new
product  development  could be  inhibited  with the  result  that our  business,
financial  condition  and  results  of  operation  could  be  significantly  and
adversely affected.

OUR BUSINESS  COULD BE HARMED IF CERTAIN  AGREEMENTS  EXPIRE OR ARE  TERMINATED.

     If our  collaborative  agreements  expire or are  terminated  and we cannot
renew or  replace  them on  commercially  reasonable  terms,  our  business  and
financial results may suffer. If the licenses and/or agreements  described below
expire or are  terminated,  we may not be able to find suitable  alternatives to
them on a timely basis or on reasonable  terms, if at all. The loss of the right
to use these  technologies  that we have  licensed  or the loss of any  services
provided to us under these agreements would  significantly  and adversely affect
our business,  financial  condition and results of operations.  For example,  in
January 2003, we provided  Draximage Inc. with notice of our intent to terminate
our  product  manufacturing  and supply  agreement  and license  agreement  with
Draximage  relating to the  brachytherapy  products which represented 20% of our
product-related revenues for the year ended December 31, 2002. In April 2003, we
entered into an agreement  with  Draximage  formally  terminating  each of these
agreements. We no longer market and sell the brachytherapy products.

We  currently  depend on the  following  agreements  for our  present and future
operating results:

     DOW CHEMICAL.  In May 1993,  we obtained an exclusive  license from The Dow
Chemical  Company to North  American  rights to use  Quadramet as a  therapeutic
radiopharmaceutical  for metabolic  bone disease or tumor  regression for cancer
caused by metastatic or primary cancer in bone in humans,  and for the treatment
of disease  characterized  by osteoblastic  response in humans.  Our license was
expanded to include Latin America in 1995.

     Our license  agreement  with Dow with respect to Quadramet  shall remain in
effect,  unless earlier terminated pursuant to the terms thereof,  for a term of
twenty  (20) years from May 30,  1993 or until the last to expire of the related
patents. We anticipate such termination date to be May 30, 2013.

     BRISTOL-MYERS  SQUIBB MEDICAL  IMAGING,  INC.  Quadramet is manufactured by
BMSMI  pursuant to the terms of a  manufacturing  and supply  agreement  with us
effective  as of  January 1, 2004.  Under  this  agreement,  BMSMI has agreed to
manufacture, supply and distribute Quadramet for us in exchange for a 

                                      -6-



minimum  payment of at least $4.2 million  annually  through 2008. The agreement
shall thereafter renew for five successive one-year periods unless terminated by
either party upon two years notice, or earlier terminated  pursuant to the terms
thereof.  The agreement is terminable  by either  party,  at any time,  upon two
years  notice to the other.  We also pay BMSMI a  variable  amount per month for
each order placed to cover the cost of customer service and distribution.

     AGREEMENT WITH DR. HOROSZEWICZ REGARDING  PROSTASCINT.  In 1989, we entered
into an agreement with Dr. Julius S.  Horoszewicz  pursuant to which we assigned
certain  rights  to the  patent  claiming  the  7E11-C5  antibody,  as  well  as
additional  patents  relating to the ProstaScint  product and  commercialization
rights  thereto.  Under our  agreement,  which will  remain in effect  until the
expiration of the last related  patent,  we have made, and may continue to make,
certain payments to Dr. Horoszewicz.

     LAUREATE  PHARMA,  L.P.  In  January  2003,  we  entered  into  a  contract
manufacturing  agreement with Laureate Pharma,  L.P., pursuant to which Laureate
was obligated to manufacture  ProstaScint  for us through  December 31, 2003. In
September  2004, we entered into another  agreement  with  Laureate  pursuant to
which Laureate is manufacturing  additional  quantities of ProstaScint for us in
exchange for expected  payments of at least an aggregate of $5.1 million through
2006.  This  agreement  was  effective  immediately  upon  execution  and  shall
terminate,  unless  earlier  terminated  pursuant  to the  terms  thereof,  upon
Laureate's  completion of the production  campaign and shipment of the resulting
products  from  Laureate's  facility  in  Princeton,  NJ. We  believe  that this
agreement will provide us with a sufficient supply of ProstaScint to satisfy our
commercial requirements for approximately the next four years based upon current
sales levels. In October 2004, Laureate entered into a definitive agreement with
Safeguard Scientifics, Inc. pursuant to which it is intended that Safeguard will
acquire  Laureate's  business and assets.  Following the  transaction,  which is
expected to be consummated  in the fourth quarter of 2004,  Laureate is expected
to continue to operate as a full service contract manufacturing organization. We
do  not  anticipate  that  we  will  experience  any  disruption  in  Laureate's
performance of its obligations to produce ProstaScint.

     ADVANCED MAGNETICS,  INC. In August, 2000, we expanded our product pipeline
by  entering  into  marketing,  license  and  supply  agreements  with  Advanced
Magnetics,  Inc. for Combidex.  We have exclusive United States marketing rights
to Combidex for all indications. Combidex (ferumoxtran-10) is an investigational
molecular  imaging  agent  consisting  of iron  oxide  nanoparticles,  which  is
currently being developed for use in conjunction with magnetic resonance imaging
to aid in the differentiation of cancerous and non-cancerous lymph nodes, and is
currently  under review by the U.S. Food and Drug  Administration.  In September
2004,  Advanced Magnetics  submitted a complete response to an approvable letter
received  in June 2000 from the FDA for  Combidex.  The  complete  response  was
accepted by the FDA and was assigned a user fee goal date of March 30, 2005. Our
license and marketing  agreement  with Advanced  Magnetics  will continue  until
August 25, 2010, and shall  thereafter  automatically  renew for successive five
year periods,  unless notice of  non-renewal  or  termination  is given by us or
Advanced Magnetics, 90 days prior to the commencement of any renewal period.

     SLOAN  KETTERING  INSTITUTE  FOR  CANCER  RESEARCH.  In  1993,  we  began a
development  program with SKICR  involving PSMA and our  proprietary  monoclonal
antibody.  In November  1996,  we  exercised  an option for,  and  obtained,  an
exclusive worldwide license from the SKICR to its PSMA-related  technology.  The
term of the license shall end on the date of expiration of the last to expire of
the licensed patents unless it earlier terminates by operation of law or by acts
of the parties in accordance with the terms of the agreement.

OUR INTELLECTUAL PROPERTY IS DIFFICULT TO PROTECT.

     In  addition to our key  agreements  referenced  above,  our  business  and
competitive  positions  are also  dependent  upon our  ability  to  protect  our
proprietary  technology.  Because of the substantial length of

                                      -7-



time and expense  associated with the development of new products,  we, like the
rest  of  the  biopharmaceutical  industry,  place  considerable  importance  on
obtaining  and   maintaining   patent  and  trade  secret   protection  for  new
technologies,  products and  processes.  We have filed patent  applications  for
certain aspects of our technology for diagnostic and therapeutic products and/or
the methods for their production and use.

     In addition,  the protection afforded by a duly issued patent is limited in
duration.  With  respect  to our  ProstaScint  product,  we rely or have  relied
primarily on United States patent numbers 5,162,504 (expiring October 28, 2010),
4,741,900  (expired  June  9,  2004),  4,671,958  (expired  June 9,  2004),  and
4,867,973  (expired June 9, 2004). With respect to Quadramet,  we rely primarily
on United States patent numbers 4,898,724  (expiring March 28, 2011),  4,937,333
(expiring  August 4, 2009),  4,897,254  (expiring  January 30, 2007),  5,066,478
(expiring November 19, 2008), and 5,300,279  (expiring November 19, 2008), which
were licensed to us by The Dow Chemical Company. In addition,  we rely on United
States patent number 5,495,042 (expiring November 4, 2013), which is assigned to
us, and United States patent numbers 5,714,604  (expiring  February 3, 2015) and
5,762,907 (expiring November 21, 2006).

     The patent positions of pharmaceutical, biopharmaceutical and biotechnology
companies,  including us, are generally  uncertain and involve complex legal and
factual  questions.  Our  patents  and patent  applications  may not protect our
technologies and products because, among other things:

  o  there is no  guarantee  that any of our pending  patent  applications  will
     result in issued patents;

  o  we may develop additional proprietary technologies that are not patentable;

  o  there is no guarantee that any patents issued to us, our  collaborators  or
     our licensors will provide a basis for a commercially viable product;

  o  there is no guarantee  that any patents  issued to us or our  collaborators
     will provide us with any competitive advantage;

  o  there is no guarantee  that any patents  issued to us or our  collaborators
     will not be challenged, circumvented or invalidated by third parties; and

  o  there is no  guarantee  that any  patents  previously  issued  to others or
     issued in the future  will not have an adverse  effect on our ability to do
     business.

     In  addition,  patent law in the  technology  fields in which we operate is
uncertain and still  evolving.  The degree of protection that may be afforded by
any  patents we are  issued or license  from  others  may not be  sufficient  to
protect our commercial interests.  Furthermore, others may independently develop
similar or alternative technologies,  duplicate our technologies, or, if patents
are issued to us,  design around the patented  technologies  developed by us. We
could  incur  substantial  costs in  litigation  if we are  required  to  defend
ourselves  in patent  suits by third  parties or if we initiate  such suits.  In
addition,  if  challenged  by others in  litigation,  the  patents  we have been
issued, which we have been assigned or we have licensed from others may be found
invalid.  It is also possible that our activities may infringe  patents owned by
others.  Defense  and  prosecution  of  patent  matters  can  be  expensive  and
time-consuming  and,  regardless  of whether the outcome is favorable to us, can
result  in  the  diversion  of  substantial  financial,   managerial  and  other
resources. An adverse outcome could:

  o  subject us to significant liability to third parties;

  o  require us to cease any related  research and  development  activities  and
     product sales; or

                                      -8-



  o  require us to obtain licenses from third parties.

     Any licenses  required  under any such  third-party  patents or proprietary
rights  may  not be  available  on  commercially  reasonable  terms,  if at all.
Moreover,  the laws of certain countries may not protect our proprietary  rights
to the same extent as the laws of the United States.  We cannot predict  whether
our or our competitors'  pending patent applications will result in the issuance
of valid patents  which may  significantly  and  adversely  affect our business,
financial condition and results of operations.

THERE ARE RISKS ASSOCIATED WITH THE MANUFACTURE AND SUPPLY OF OUR PRODUCTS.

     If we are to be successful,  our products will have to be  manufactured  by
contract  manufacturers in compliance with regulatory  requirements and at costs
acceptable to us. If we are unable to  successfully  arrange for the manufacture
of our products and product candidates,  either because potential  manufacturers
are not cGMP compliant,  are not available or charge excessive amounts,  we will
not be  able to  successfully  commercialize  our  products  and  our  business,
financial  condition  and  results  of  operations  will  be  significantly  and
adversely affected.

     ProstaScint  is  currently  manufactured  at a current  Good  Manufacturing
Practices,  or cGMP,  compliant  manufacturing  facility  operated  by  Laureate
Pharma, L.P. We entered into a development and manufacturing  agreement with DSM
Biologics  Company B.V. in July 2000, which we intended would replace an earlier
arrangement we had with Laureate with respect to ProstaScint.  Our  relationship
with DSM was subsequently terminated. Although we entered into another agreement
with  Laureate in September  2004  pursuant to which  Laureate is  manufacturing
additional quantities of ProstaScint for us, our failure to maintain a long term
supply  agreement on commercially  reasonable terms will have a material adverse
effect on our  business,  financial  condition  and  results of  operations.  In
October  2004,  Laureate  entered into a  definitive  agreement  with  Safeguard
Scientifics,  Inc.  pursuant to which it is intended that Safeguard will acquire
Laureate's business and assets. Following the transaction,  which is expected to
be consummated  in the fourth quarter of 2004,  Laureate is expected to continue
to operate as a full  service  contract  manufacturing  organization.  We do not
anticipate that we will  experience any disruption in Laureate's  performance of
its obligations to produce ProstaScint.

     Quadramet is manufactured by BMSMI,  pursuant to an agreement with us. Both
primary  components  of  Quadramet,  particularly  Samarium-153  and EDTMP,  are
provided to BMSMI by outside suppliers.  Due to radioactive decay,  Samarium-153
must  be  produced  on a  weekly  basis.  BMSMI  obtains  its  requirements  for
Samarium-153  from a  sole  supplier  and  EDTMP  from  another  sole  supplier.
Alternative  sources for these components may not be readily available,  and any
alternative  supplier would have to be identified and qualified,  subject to all
applicable regulatory  guidelines.  If BMSMI cannot obtain sufficient quantities
of the components on commercially  reasonable  terms, or in a timely manner,  it
would be unable to manufacture  Quadramet on a timely and cost-effective  basis,
which would have a material adverse effect on our business,  financial condition
and results of operations.

     The  Company,  our  contract  manufacturers  and testing  laboratories  are
required to adhere to FDA regulations  setting forth  requirements for cGMP, and
similar regulations in other countries, which include extensive testing, control
and documentation requirements. Ongoing compliance with cGMP, labeling and other
applicable regulatory requirements is monitored through periodic inspections and
market  surveillance  by state and federal  agencies,  including the FDA, and by
comparable agencies in other countries. Failure of our contract vendors or us to
comply with  applicable  regulations  could result in sanctions being imposed on
us, including fines, injunctions,  civil penalties, failure of the government to
grant pre-market clearance or pre-market approval of drugs,  delays,  suspension
or  withdrawal  of  approvals,   seizures  or  recalls  of  products,  operating
restrictions  and criminal  prosecutions  any of which could  significantly  and
adversely affect our business, financial condition and results of operations.

                                      -9-



OUR  PRODUCTS,   GENERALLY,   ARE  IN  THE  EARLY  STAGES  OF  DEVELOPMENT   AND
COMMERCIALIZATION  AND WE MAY NEVER  ACHIEVE THE REVENUE  GOALS SET FORTH IN OUR
BUSINESS PLAN.

     We began  operations  in 1980 and have  since  been  engaged  primarily  in
research  directed toward the  development,  commercialization  and marketing of
products to improve the diagnosis and treatment of cancer and other diseases. In
October 1996, we introduced for commercial use our ProstaScint imaging agent. In
March 1997, we introduced for commercial use our Quadramet  therapeutic product.
In November  2002, we began  promoting  NMP22  BladderChek  to urologists in the
United  States,  and now have the right to promote NMP22  BladderChek  solely to
oncologists. Sales of NMP22 BladderChek have been minimal to date, and we do not
expect significant revenues from sales of NMP22 BladderChek.

     In  August  2000,  we  expanded  our  product  pipeline  by  entering  into
marketing,  license and supply  agreements  with  Advanced  Magnetics,  Inc. for
Combidex.  We have exclusive  United States marketing rights to Combidex for all
indications. In September 2004, Advanced Magnetics submitted a complete response
to an approvable  letter  received in June 2000 from the FDA for  Combidex.  The
complete  response was accepted by the FDA and was assigned a user fee goal date
of March 30, 2005.

     To date, we have allocated, and expect to continue to allocate, significant
amounts  of time and  resources  in  preparation  for the  commercial  launch of
Combidex.  We cannot assure you,  however,  that Advanced  Magnetics will obtain
approval  from the FDA for  Combidex on a timely  basis,  if at all. If Advanced
Magnetics  does not secure  regulatory  approval  for  Combidex,  we will not be
permitted  to sell and market  Combidex as we have  anticipated  and we will not
realize  any  return on the  significant  amount of time and  resources  we have
allocated to Combidex.

     Our PSMA technologies are still in the early stages of development. In July
2004, as part of our continuing  efforts to reduce  non-strategic  expenses,  we
initiated  the  closure  of  facilities  at our AxCell  BioSciences  subsidiary.
Research  projects through  academic,  governmental and corporate  collaborators
will continue to be supported and additional  applications  for the intellectual
property and technology at AxCell are being pursued. We may be unable to further
develop or commercialize any of these products and technologies in the future.

     Our business is therefore  subject to the risks  inherent in an early-stage
biopharmaceutical business enterprise, such as the need:

  o  to obtain  sufficient  capital to support the  expenses of  developing  our
     technology and commercializing our products;

  o  to ensure that our products are safe and effective;

  o  to obtain regulatory approval for the use and sale of our products;

  o  to  manufacture  our products in sufficient  quantities and at a reasonable
     cost;

  o  to develop a sufficient market for our products; and

  o  to attract and retain qualified management, sales, technical and scientific
     staff.

     The problems frequently encountered using new technologies and operating in
a competitive environment also may affect our business,  financial condition and
results of operations. If we fail to properly address these risks and attain our
business objectives, our business could be significantly and adversely affected.

                                      -10-



ALL OF OUR POTENTIAL  ONCOLOGY  PRODUCTS WILL BE SUBJECT TO THE RISKS OF FAILURE
INHERENT IN THE  DEVELOPMENT OF DIAGNOSTIC OR THERAPEUTIC  PRODUCTS BASED ON NEW
TECHNOLOGIES.

     Product  development for cancer  treatment  involves a high degree of risk.
The product candidates we develop,  pursue or offer may not prove to be safe and
effective,  may not receive the necessary regulatory approvals, may be precluded
by  proprietary  rights of third parties or may not  ultimately  achieve  market
acceptance.   These  product  candidates  will  require  substantial  additional
investment,  laboratory  development,  clinical testing and regulatory approvals
prior to their commercialization.  We may experience  difficulties,  such as the
inability to initiate  clinical trials or receive timely  regulatory  approvals,
that  could  delay or  prevent  the  successful  development,  introduction  and
marketing of new products.

     Before we obtain regulatory approvals for the commercial sale of any of our
products under development,  we must demonstrate through preclinical studies and
clinical  trials that the product is safe and  effective  for use in each target
indication. The results from preclinical studies and early-stage clinical trials
may  not be  predictive  of  results  that  will  be  obtained  in  large-scale,
later-stage testing. Our clinical trials may not demonstrate safety and efficacy
of a proposed product,  and therefore,  may not result in marketable products. A
number of  companies  in our  industry  have  suffered  significant  setbacks in
advanced  clinical  trials,  even after  promising  results  in earlier  trials.
Clinical trials or marketing of any potential diagnostic or therapeutic products
may expose us to liability claims for the use of these diagnostic or therapeutic
products.  We may  not be  able  to  maintain  product  liability  insurance  or
sufficient  coverage may not be available  at a  reasonable  cost.  In addition,
internal   development  of  diagnostic  or  therapeutic  products  will  require
significant investments in product development,  marketing, sales and regulatory
compliance  resources.  We will  also  have to  establish  or  contract  for the
manufacture of products,  including  supplies of drugs used in clinical  trials,
under the cGMP of the FDA.  We cannot  assure you that  product  issues will not
arise following successful clinical trials and FDA approval.

     The rate of  completion  of  clinical  trials  also  depends on the rate of
patient  enrollment.  Patient enrollment depends on many factors,  including the
size of the patient  population,  the nature of the  protocol,  the proximity of
patients to clinical sites and the eligibility criteria for the study. Delays in
planned patient enrollment may result in increased costs and delays, which could
have a harmful effect on our ability to develop the products in our pipeline. If
we are unable to develop and commercialize products on a timely basis or at all,
our  business,   financial   condition  and  results  of  operations   could  be
significantly and adversely affected.

COMPETITION IN OUR FIELD IS INTENSE AND LIKELY TO INCREASE.

     All of our  products  and  product  candidates are  subject to  significant
competition from organizations that are pursuing  technologies and products that
are  the  same  as or  similar  to our  technology  and  products.  Many  of the
organizations  competing with us have greater  capital  resources,  research and
development staffs and facilities and marketing capabilities.

     We face, and will continue to face, intense competition from one or more of
the following entities:

  o  pharmaceutical companies;

  o  biotechnology companies;

  o  diagnostic companies;

  o  medical device companies;

                                      -11-



  o  radiopharmaceutical distributors;

  o  academic and research institutions; and

  o  government agencies.

     The markets in which our products  compete are large.  Our most significant
competitors  include  various   pharmaceutical  and  medical  device  companies,
radiopharmaceutical distributors and biotechnology companies.

     Quadramet   primarily   competes   with   Strontium-89   chloride   in  the
radiopharmaceutical   pain   palliation   market.   Strontium-89   chloride   is
manufactured  and marketed  either as  Metastron,  by Amersham  Health,  or in a
generic form by Bio-Nucleonics  Pharma, Inc. Amersham manufactures Metastron and
sells the product through its wholly-owned network of radiopharmacies, direct to
end-users and through other radiopharmacy  distributors.  The generic version is
distributed  directly  by the  manufacturer  or is  sold  through  radiopharmacy
distributors  such as  Cardinal  Health  and  Custom  Care  Pharmacy.  The first
radiopharmaceutical  introduced  as a  metastatic  bone cancer  pain  palliation
agent,  Phosphorus-32  (P-32), is no longer routinely utilized clinically in the
United States.

     Competitive  imaging modalities to ProstaScint  include computed tomography
(CT), magnetic resonance (MR) imaging, and position emission tomography (PET).

     Polymedco  manufactures  BTAStat, a point of care urine-based test approved
for monitoring bladder cancer patients.  BTAStat,  marketed by Mentor,  competes
with  NMP22  BladderChek  (a  product  of  Matritech  for  which we are the sole
distributor  to  oncologists  in the United States  through  December 31, 2004).
NMP22 BladderChek is, however,  the only point of care urine-based test approved
for both  monitoring  and  diagnosis of bladder  cancer.  Matritech has retained
rights  to  market  NMP22   BladderChek   directly  to  physicians   other  than
oncologists, such as primary care physicians.

     Additionally,  we  face  competition  in the  development  of  PSMA-related
technology and products  primarily  from  Millennium  Pharmaceuticals,  Inc. and
Medarex, Inc.

     Before we recover  development  expenses for our products and technologies,
the products or technologies  may become  obsolete as a result of  technological
developments  by others or us. Our products  could also be made  obsolete by new
technologies,  which are less expensive or more effective. We may not be able to
make the enhancements to our technology  necessary to compete  successfully with
newly  emerging  technologies  and  failure  to do so  could  significantly  and
adversely affect our business, financial condition and results of operations.

WE HAVE LIMITED SALES, MARKETING AND DISTRIBUTION CAPABILITIES FOR OUR PRODUCTS.

     We have  established  an  internal  sales  force  that is  responsible  for
marketing and selling ProstaScint,  Quadramet and NMP22 BladderChek. Although we
are  expanding  our sales  force,  it still has  limited  sales,  marketing  and
distribution  capabilities  compared  to  those  of  many  of  our  competitors.
Effective  August 1, 2003,  we  reacquired  marketing  rights to Quadramet  from
Berlex Laboratories,  Inc. in North and Latin America, for an upfront payment of
$8.0 million and the  obligation  to pay  royalties to Berlex on future sales of
Quadramet.  If our  internal  sales  force  is  unable  to  successfully  market
Quadramet  and  ProstaScint,  our  business  and  financial  condition  would be
adversely  affected.  If we are unable to  establish  and  maintain  significant
sales,  marketing and  distribution  efforts  within the United  States,  either
internally  or through  arrangements  with third  parties,  our  business may be
significantly and adversely affected. In locations outside of the United States,
we have not established a selling presence.  To the extent that our sales force,
from time to time, markets and sells additional  products,  we cannot be certain
that  adequate  resources or sales  capacity  will be  available to  effectively
accomplish these tasks.

                                      -12-



FAILURE OF THIRD PARTY PAYORS TO PROVIDE ADEQUATE COVERAGE AND REIMBURSEMENT FOR
OUR PRODUCTS  COULD LIMIT MARKET  ACCEPTANCE  AND AFFECT PRICING OF OUR PRODUCTS
AND AFFECT OUR REVENUES.

     Sales of our  products  depend  in part on the  availability  of  favorable
coverage and reimbursement by governmental  healthcare programs such as Medicare
and Medicaid as well as private health insurance  plans.  Each payor has its own
process and standards for determining whether and, if so, to what extent it will
cover and reimburse a particular product or service.  Whether and to what extent
a product may be deemed  covered by a particular  payor depends upon a number of
factors,  including the payor's determination that the product is reasonable and
necessary  for the  diagnosis or treatment of the illness or injury for which it
is  administered  according  to accepted  standards  of medical  practice,  cost
effective, not experimental or investigational,  not found by the FDA to be less
than effective, and not otherwise excluded from coverage by law, regulation,  or
contract.   There  may  be   significant   delays  in  obtaining   coverage  for
newly-approved  products,  and  coverage  may not be  available or could be more
limited than the purposes for which the product is approved by the FDA.

     Moreover,  eligibility for coverage does not imply that any product will be
reimbursed  in all  cases or at a rate  that  allows us to make a profit or even
cover our costs, which include, for example, research, development,  production,
sales, and distribution costs. Interim payments for new products, if applicable,
also may not be  sufficient  to cover our  costs and may not be made  permanent.
Reimbursement  rates  may  vary  according  to the  use of the  product  and the
clinical  setting  in which it is used,  may be based on  payments  allowed  for
lower-cost  products  that are  already  reimbursed,  may be  incorporated  into
existing  payments  for other  products or services,  and may reflect  budgetary
constraints  and/or  imperfections  in Medicare or Medicaid data. Net prices for
products may be reduced by mandatory discounts or rebates required by government
healthcare  programs,  or other payors, or by any future relaxation of laws that
restrict  imports of certain  medical  products from countries where they may be
sold at lower prices than in the United States.

     Third  party  payors  often  follow  Medicare  coverage  policy and payment
limitations in setting their own coverage policies and reimbursement  rates, and
may have sufficient market power to demand significant price reductions. Even if
successful,  securing coverage at adequate  reimbursement  rates from government
and third party  payors can be a time  consuming  and costly  process that could
require us to provide  supporting  scientific,  clinical and  cost-effectiveness
data for the use of our products  among other data and  materials to each payor.
Our inability to promptly obtain favorable coverage and profitable reimbursement
rates from  government-funded  and private  payors for our products could have a
material  adverse  effect on our  business,  financial  condition and results of
operations, and our ability to raise capital needed to commercialize products.

     Our business,  financial  condition and results of operations will continue
to be affected by the efforts of governmental and third-party  payors to contain
or reduce the costs of  healthcare.  There have been,  and we expect  that there
will  continue  to be, a number of  federal  and  state  proposals  to  regulate
expenditures  for medical  products and services,  which may affect payments for
therapeutic and diagnostic imaging agents such as our products.  In addition, an
emphasis on managed  care  increases  possible  pressure on the pricing of these
products.  While we cannot  predict  whether  these  legislative  or  regulatory
proposals  will be  adopted,  or the effects  these  proposals  or managed  care
efforts may have on our business,  the  announcement  of these proposals and the
adoption  of these  proposals  or efforts  could  affect our stock  price or our
business.  Further,  to the extent  these  proposals  or efforts have an adverse
effect on other  companies  that are our  prospective  corporate  partners,  our
ability to establish necessary strategic alliances may be harmed.

                                      -13-



IF WE ARE UNABLE TO COMPLY WITH APPLICABLE GOVERNMENTAL REGULATION WE MAY NOT BE
ABLE TO CONTINUE OUR OPERATIONS.

     Any products  tested,  manufactured  or  distributed by us or on our behalf
pursuant to FDA approvals are subject to pervasive and continuing  regulation by
numerous regulatory authorities,  including primarily the FDA. We may be slow to
adapt, or we may never adapt to changes in existing  requirements or adoption of
new requirements or policies. Our failure to comply with regulatory requirements
could subject us to enforcement  action,  including product  seizures,  recalls,
withdrawal,   suspension,  or  revocation  of  approvals,   restrictions  on  or
injunctions  against  marketing our products based on our technology,  and civil
and criminal  penalties.  We may incur significant costs to comply with laws and
regulations in the future or compliance  with laws or regulations  may create an
unsustainable burden on our business.

     Numerous federal, state and local governmental authorities, principally the
FDA,  and  similar  regulatory   agencies  in  other  countries,   regulate  the
preclinical testing, clinical trials, manufacture and promotion of any compounds
or agents we or our collaborative  partners  develop,  and the manufacturing and
marketing  of any  resulting  drugs.  The  product  development  and  regulatory
approval process is lengthy, expensive, uncertain and subject to delays.

     The regulatory risks we face also include the following:

  o  any compound or agent, including generics, we or our collaborative partners
     develop must receive  regulatory  agency approval before it may be marketed
     as a drug in a particular country;

  o  the regulatory  process,  which includes  preclinical  testing and clinical
     trials of each  compound  or agent in order to  establish  its  safety  and
     efficacy,  varies from country to country, can take many years and requires
     the expenditure of substantial resources;

  o  in  all  circumstances,  approval  of  the  use  of  previously  unapproved
     radioisotopes in certain of our products  requires  approval of the Nuclear
     Regulatory  Commission and/or equivalent state regulatory  agencies,  which
     may be a lengthy process.  A radioisotope is an unstable form of an element
     which undergoes  radioactive decay, thereby emitting radiation which may be
     used, for example, to image or destroy harmful growths or tissue;

  o  data obtained from  preclinical and clinical  activities are susceptible to
     varying  interpretations  which could  delay,  limit or prevent  regulatory
     agency approval; and

  o  delays or rejections  may be  encountered  based upon changes in regulatory
     agency policy during the period of product development and/or the period of
     review of any  application  for regulatory  agency  approval.  These delays
     could   adversely   affect  the   marketing  of  any  products  we  or  our
     collaborative   partners   develop,   impose  costly  procedures  upon  our
     activities,  diminish any  competitive  advantages we or our  collaborative
     partners may attain and adversely affect our ability to receive royalties.

     Regulatory  agency  approval for a product or agent may not be received and
may entail  limitations  on the  indicated  uses that could limit the  potential
market for any such product. For example, as disclosed in our press releases and
periodic filings,  we have exclusive United States marketing rights to Combidex,
an   investigational   molecular   imaging   agent   consisting  of  iron  oxide
nanoparticles,  which is currently being  developed for use in conjunction  with
magnetic  resonance  imaging  to aid in the  differentiation  of  cancerous  and
non-cancerous  lymph  nodes,  and is  under  review  by the FDA.  In June  2000,
Advanced  Magnetics  received an approvable  letter from the FDA with respect to
Combidex.  An approvable letter is a written  communication to an applicant from
the FDA stating that the agency will approve the

                                      -14-


application or abbreviated  application if specific and satisfactory  additional
information  or  material  is  submitted  or  specific  conditions  are met.  An
approvable letter does not constitute  approval of any part of an application or
abbreviated  application  and does not permit  marketing of the drug that is the
subject of the  application or abbreviated  application.  In September  2004, we
announced  that  Advanced  Magnetics   submitted  a  complete  response  to  the
approvable  letter for Combidex.  The September 30, 2004 submission was accepted
and assigned a user fee goal date of March 30, 2005.

     If and  when  we  obtain  approval  or  clearance  for  our  products,  the
marketing, manufacture,  labeling, packaging, adverse event and other reporting,
storage,  advertising  and promotion and record keeping  related to our products
would  remain  subject  to  extensive  regulatory  requirements.   Discovery  of
previously unknown problems with a drug, its manufacture or its manufacturer may
result in  restrictions  on such drug,  manufacture or  manufacturer,  including
withdrawal of the drug from the market.

     The Food, Drug and Cosmetics Act and the Public Health Service Act require:
(i) that our products be  manufactured in FDA registered  facilities  subject to
inspection;  and (ii) that we comply with cGMP, which imposes certain procedural
and  documentation  requirements  upon us and our  manufacturing  partners  with
respect to manufacturing and quality assurance activities. If we or our contract
partners do not comply with cGMP or we do not comply with any of the FDA's other
postmarket  requirements  we may  be  subject  to  sanctions,  including  fines,
injunctions,  civil penalties, recalls or seizures of products, total or partial
suspension of production,  product  recalls,  failure of the government to grant
clearance or premarket  approval for devices or premarket  approval for drugs or
biologics,  suspension,  revocation  or  withdrawal  of marketing  approvals and
criminal prosecution.

     From time to time,  legislation  is drafted and introduced in Congress that
could  significantly  change the  statutory  provisions  governing the approval,
manufacturing and marketing of products  regulated by the FDA. In addition,  FDA
regulations  and guidance are often  revised or  reinterpreted  by the agency in
ways  that  may  significantly  affect  our  business  and our  products.  It is
impossible  to predict  whether  legislative  changes  will be  enacted,  or FDA
regulations,  guidance or  interpretations  changed,  or what the impact of such
changes, if any, may be.

WE DEPEND ON ATTRACTING AND RETAINING KEY PERSONNEL.

     We are highly  dependent on the  principal  members of our  management  and
scientific  staff.  The  loss of their  services  might  significantly  delay or
prevent the  achievement  of development  or strategic  objectives.  Our success
depends  on our  ability  to retain  key  employees  and to  attract  additional
qualified employees.  Competition for personnel is intense, and therefore we may
not be able to retain existing personnel or attract and retain additional highly
qualified employees in the future.

     On December 17, 2002,  we entered into a letter  agreement  with Michael D.
Becker  in  connection  with Mr.  Becker's  promotion  to  President  and  Chief
Executive Officer of the Company. Under the terms of such letter agreement,  Mr.
Becker  receives an annual base salary of $280,000.  Mr. Becker is also eligible
to  participate  in our Cytogen  Corporation  Performance  Bonus Plan, as and if
approved  by our Board of  Directors,  with a target  bonus  rate of 35% of base
salary based upon  performance  objectives.  Mr.  Becker is also entitled to all
existing Company benefits, at the sole discretion of the Board of Directors.  In
addition,  Mr.  Becker was  granted  options to purchase  200,000  shares of our
common  stock  under our 1995 Stock  Option  Plan.  Pursuant to the terms of the
letter agreement,  in the event we terminate Mr. Becker's employment for reasons
other than for cause,  as defined  therein,  Mr.  Becker  shall be  entitled  to
receive twelve months' base pay and  continuation of benefits under COBRA, and a
pro  rata  portion  of  any  incentive  benefits  earned  through  the  date  of
termination.

     We do not carry key person life insurance  policies and we do not typically
enter into long-term  arrangements  with our key personnel.  If we are unable to
hire and retain personnel in key positions, our

                                      -15-


business, financial  condition and results of operations  could be significantly
and adversely affected unless qualified replacements can be found.

OUR  BUSINESS  EXPOSES  US TO  PRODUCT  LIABILITY  CLAIMS  THAT MAY  EXCEED  OUR
FINANCIAL  RESOURCES,  INCLUDING  OUR  INSURANCE  COVERAGE,  AND MAY LEAD TO THE
CURTAILMENT OR TERMINATION OF OUR OPERATIONS.

     Our business is subject to product liability risks inherent in the testing,
manufacturing  and marketing of our products and product liability claims may be
asserted  against us, our  collaborators  or our  licensees.  While we currently
maintain  product  liability  insurance  in the  amount of $10.0  million,  such
coverage  may not be adequate  to protect us against  future  product  liability
claims. In addition,  product liability  insurance may not be available to us in
the future on commercially reasonable terms, if at all. Although we have not had
a history of claims  payments  that have  exceeded  our  insurance  coverage  or
available  financial  resources,  if  liability  claims  against  us exceed  our
financial resources or coverage amounts, we may have to curtail or terminate our
operations.  In addition,  while we currently  maintain  directors  and officers
liability  insurance in the amount of $25.0  million,  such  coverage may not be
available on  commercially  reasonable  terms or be adequate to cover any claims
that we may be  required  to satisfy in the future.  Our  insurance  coverage is
subject to industry standard and certain other limitations.

OUR SECURITY MEASURES MAY NOT PROTECT OUR UNPATENTED PROPRIETARY TECHNOLOGY.

     We also rely upon trade secret  protection for some of our confidential and
proprietary  information that is not subject matter for which patent  protection
is available. To help protect our rights, we require all employees, consultants,
advisors and collaborators to enter into confidentiality agreements that require
disclosure,  and in most cases, assignment to us, of their ideas,  developments,
discoveries  and  inventions,  and that prohibit the disclosure of  confidential
information  to anyone  outside  Cytogen or our  subsidiaries.  Although  we are
unaware of any  unauthorized  use or  disclosure of our  unpatented  proprietary
technology to date, these agreements may not provide adequate protection for our
trade  secrets,  know-how  or other  proprietary  information  or  prevent  such
unauthorized use or disclosure.

WE MAY NOT BE ABLE TO IMPLEMENT AXCELL'S BUSINESS PLAN.

     In September 2002, we began the  restructuring  of our  subsidiary,  AxCell
BioSciences  Corporation,  in an effort to reduce expenses and position  Cytogen
for  stronger  long-term  growth  in  oncology.  In July  2004,  as part  of our
continuing efforts to reduce non-strategic expenses, we initiated the closure of
facilities  at our AxCell  BioSciences  subsidiary.  Research  projects  through
academic, governmental and corporate collaborators will continue to be supported
and  additional  applications  for the  intellectual  property and technology at
AxCell are being pursued.  We may be unable to further develop or  commercialize
any of Axcell's technologies in the future.

WE MAY NEED TO RAISE ADDITIONAL CAPITAL, WHICH MAY NOT BE AVAILABLE.

     Our cash, cash equivalents and short-term investments were $40.5 million at
September  30, 2004.  We expect that our existing  capital  resources  should be
adequate to fund our operations and commitments into 2007.

     We have incurred  negative cash flows from  operations  since our inception
and have expended,  and expect to continue to expend in the future,  substantial
funds based upon the:

  o  success of our product commercialization efforts;

  o  success  of  any  future   acquisitions  of   complementary   products  and
     technologies we may make;

                                      -16-



  o  magnitude,  scope and results of our product  development  and research and
     development efforts;

  o  progress of preclinical studies and clinical trials;

  o  progress toward regulatory approval for our products;

  o  costs of filing,  prosecuting,  defending and  enforcing  patent claims and
     other intellectual property rights;

  o  competing technological and market developments; and

  o  expansion of strategic  alliances for the sale,  marketing and distribution
     of our products.

     Our  business  or  operations  may change in a manner  that  would  consume
available  resources more rapidly than anticipated.  We expect that we will have
additional requirements for debt or equity capital,  irrespective of whether and
when we reach profitability,  for further product development costs, product and
technology  acquisition  costs  and  working  capital.  To  the extent  that our
currently  available  funds and  revenues  are  insufficient  to meet current or
planned operating  requirements,  we will be required to obtain additional funds
through equity or debt financing,  strategic  alliances with corporate  partners
and  others,  or through  other  sources.  These  financial  sources  may not be
available when we need them or they may be available,  but on terms that are not
commercially  acceptable to us. If adequate funds are not  available,  we may be
required  to delay,  further  scale  back or  eliminate  certain  aspects of our
operations or attempt to obtain funds through  arrangements  with  collaborative
partners or others that may  require us to  relinquish  rights to certain of our
technologies,  product  candidates,  products or potential markets.  If adequate
funds are not  available,  our  business,  financial  condition  and  results of
operations will be materially and adversely affected.

OUR CAPITAL RAISING EFFORTS MAY DILUTE STOCKHOLDER INTERESTS.

     If we raise additional  capital by issuing equity securities or convertible
debentures,  including the securities  registered  pursuant to this  prospectus,
such  issuance will result in ownership  dilution to our existing  stockholders,
and  new  investors  could  have  rights  superior  to  those  of  our  existing
stockholders.  The  extent of such  dilution  will vary based upon the amount of
capital raised.

WE MAY NEED TO RAISE FUNDS OTHER THAN THROUGH THE ISSUANCE OF EQUITY SECURITIES.

     If  we  raise  additional  funds  through   collaborations   and  licensing
arrangements,  we may  be  required  to  relinquish  rights  to  certain  of our
technologies or product candidates or to grant licenses on unfavorable terms. If
we relinquish rights or grant licenses on unfavorable  terms, we may not be able
to develop or market products in a manner that is profitable to us.

OUR PSMA  PRODUCT  DEVELOPMENT  PROGRAM IS NOVEL AND,  CONSEQUENTLY,  INHERENTLY
RISKY.

     We are  subject  to the risks of failure  inherent  in the  development  of
product  candidates  based on new  technologies,  including our PSMA technology.
These risks include the possibility that:

  o  the technologies we use will not be effective;

  o  our product candidates will be unsafe;

  o  our  product  candidates  will fail to  receive  the  necessary  regulatory
     approvals;

                                      -17-



  o  the product candidates will be hard to manufacture on a large scale or will
     be uneconomical to market; and

  o  we will not successfully overcome technological challenges presented by our
     potential new products.

     Our  other  research  and  development  programs  involve  similarly  novel
approaches to human  therapeutics.  Consequently,  there is no precedent for the
successful   commercialization   of  therapeutic  products  based  on  our  PSMA
technologies.  If we fail to  develop  such  products,  our  business  financial
condition  and  results  of  operations  could be  significantly  and  adversely
affected.

WE COULD BE NEGATIVELY  IMPACTED BY FUTURE  INTERPRETATION  OR IMPLEMENTATION OF
FEDERAL AND STATE FRAUD AND ABUSE LAWS, INCLUDING ANTI-KICKBACK LAWS AND FEDERAL
AND STATE FALSE CLAIMS STATUTES.

     We are subject to various  federal and state laws  pertaining to healthcare
fraud and abuse,  including  anti-kickback  laws and false  claims  laws,  among
others.  Violations  of these  laws are  punishable  by  criminal  and/or  civil
sanctions,  including,  in  some  instances,  imprisonment  and  exclusion  from
participation  in federal and state  healthcare  programs,  including  Medicare,
Medicaid, and veterans' health programs, among others.

     The  federal  and  state  governments  have  significantly   increased  the
financial  resources  allocated  to enforcing  healthcare  fraud and abuse laws.
Private  insurers and various state  enforcement  agencies  also have  increased
their level of scrutiny of healthcare  claims and  arrangements  in an effort to
identify  and  prosecute  fraudulent  and abusive  practices  in the  healthcare
industry.

     We have not been challenged by a governmental  authority under any of these
laws and believe that our operations are in compliance with such laws.  However,
because of the  far-reaching  nature of these laws,  we may be required to alter
one or more of our  practices to be in  compliance  with these laws.  Healthcare
fraud and abuse laws and  regulations are complex,  and even minor,  inadvertent
irregularities  can  potentially  give  rise to  claims  that  the law has  been
violated. Any violations of these laws could result in a material adverse effect
on our business,  financial  condition and results of operations.  If there is a
change in law, regulation or administrative or judicial interpretations,  we may
have to change our business  practices or our existing business  practices could
be challenged  as unlawful,  which could have a material  adverse  effect on our
business, financial condition and results of operations.

     The  healthcare  fraud and abuse laws to which we are  subject  include the
following, among others:

     FEDERAL  AND  STATE  ANTI-KICKBACK  LAWS AND SAFE  HARBOR  PROVISIONS.  The
federal anti-kickback law makes it a felony to knowingly and willfully offer, or
pay  remuneration "to induce" a person to refer an individual or to recommend or
arrange  for the  purchase,  lease or  ordering of any item or service for which
payment  may be made  under  the  Medicare  or state  healthcare  programs.  The
anti-kickback  prohibitions  apply  regardless  of whether the  remuneration  is
provided directly or indirectly, in cash or in kind.  Interpretations of the law
have  been  very  broad.  Under  current  law,  courts  and  federal  regulatory
authorities  have  stated  that this law is  violated  if even one  purpose,  as
opposed  to the  sole  or  primary  purpose,  of the  arrangement  is to  induce
referrals.   Violations  of  the  anti-kickback  law  carry  potentially  severe
penalties  including  imprisonment of up to five years,  criminal  fines,  civil
money penalties and exclusion from the Medicare and Medicaid programs.

     The U.S.  Department  of Health  and  Human  Services  Office of  Inspector
General, or OIG, has published "safe harbors" that exempt some arrangements from
enforcement  action  under  the  anti-kickback   statute.  These  statutory  and
regulatory  safe harbors  protect  various bona fide  employment  relationships,
personal  service  arrangements,  certain  discount  arrangements,  among  other
things, provided

                                      -18-



that certain  conditions set forth in the statute and regulations are satisfied.
The safe harbor regulations, however, do not comprehensively describe all lawful
arrangements,  and  the  failure  of  an  arrangement  to  satisfy  all  of  the
requirements  of a particular  safe harbor does not mean that the arrangement is
unlawful.  Failure to comply with the safe harbor provisions,  however, may mean
that the arrangement will be subject to scrutiny by the OIG.

     Many states have  adopted  similar  prohibitions.  Some of these state laws
lack specific "safe harbors" that may be available under federal law.  Sanctions
under these state anti-kickback laws may include civil money penalties,  license
suspension or  revocation,  exclusion  from  Medicare or Medicaid,  and criminal
fines or imprisonment.

     We believe  that our  contracts  and  arrangements  are not in violation of
applicable  anti-kickback or related laws. We cannot assure you,  however,  that
these  laws will  ultimately  be  interpreted  in a manner  consistent  with our
practices.

     FALSE CLAIMS ACTS. We are subject to state and federal laws that govern the
submission  of claims for  reimbursement.  The federal  Civil  False  Claims Act
imposes civil liability on individuals or entities that submit, or "cause" to be
submitted, false or fraudulent claims for payment to the government.  Violations
of the Civil  False  Claims Act may  result in treble  damages,  civil  monetary
penalties for each false claim  submitted  and  exclusion  from the Medicare and
Medicaid programs.  In addition, we could be subject to criminal penalties under
a variety of federal  statutes to the extent  that we  knowingly  violate  legal
requirements  under federal  health  programs or otherwise  present or cause the
presentation of false or fraudulent  claims or  documentation to the government.
In  addition,  the OIG may  impose  extensive  and  costly  corporate  integrity
requirements upon entities and individuals subject to a false claims judgment or
settlement.  These  requirements may include the creation of a formal compliance
program,  the  appointment  of  an  independent  review  organization,  and  the
imposition  of  annual  reporting   requirements  and  audits  conducted  by  an
independent  review  organization  to monitor  compliance  with the terms of the
agreement and relevant laws and regulations.

     The Federal  Civil False  Claims Act also  allows a private  individual  to
bring a "qui tam" suit on behalf of the  government  for violations of the Civil
False  Claims  Act,  and if  successful,  the "qui  tam"  relator  shares in the
government's  recovery.  A qui tam  suit  may be  brought  by,  with  only a few
exceptions,  any private  citizen who has material  information of a false claim
that has not yet been  previously  disclosed.  Recently,  the  number of qui tam
suits  brought  in  the  healthcare  industry  has  increased  dramatically.  In
addition, several states have enacted laws modeled after the Federal Civil False
Claims Act.

     CIVIL MONETARY PENALTIES.  The Civil Monetary Penalties Statute states that
civil  penalties  ranging  between  $10,000  and $50,000 per claim or act may be
imposed on any person or entity that knowingly submits, or causes the submission
of,  improperly filed claims for federal health  benefits,  or makes payments to
induce a  beneficiary  or  provider  to reduce  or limit  the use of  healthcare
services or to use a particular  provider or supplier.  Civil monetary penalties
may be imposed for violations of the  anti-kickback  statute and for the failure
to return known overpayments, among other things.

     PROHIBITION ON EMPLOYING OR CONTRACTING WITH EXCLUDED PROVIDERS. The Social
Security Act and federal  regulations  state that  individuals  or entities that
have been convicted of a criminal  offense related to the delivery of an item or
service  under the  Medicare or Medicaid  programs or that have been  convicted,
under state or federal law, of a criminal  offense  relating to neglect or abuse
of residents  in  connection  with the delivery of a healthcare  item or service
cannot  participate in any federal healthcare  programs,  including Medicare and
Medicaid.

     HEALTH INSURANCE  PORTABILITY AND ACCOUNTABILITY ACT OF 1996. HIPAA created
new healthcare  related  crimes,  and granted  authority to the Secretary of the
Department  of Health  and  Human  Services  ("HHS")  to  impose  certain  civil
penalties. Particularly, the Secretary may now exclude from Medicare

                                      -19-



any  individual  with a direct  or  indirect  ownership  interest  in an  entity
convicted of  healthcare  fraud or excluded  from the  program.  Under HIPAA and
other  healthcare  laws,  it is a crime  to  knowingly  and  willfully  commit a
healthcare  fraud,  and  knowingly and willfully  falsify,  or conceal  material
information or make any materially false or fraudulent  statements in connection
with claims and payment for  healthcare  services by a healthcare  benefit plan.
HIPAA also  created new  programs to control  fraud and abuse,  and requires new
investigations, audits and inspections.

     We believe that operations  materially  comply with  applicable  regulatory
requirements. There can be no assurance that the outcome of any inquiry audit or
investigation  will be  undertaken  by HHS,  OIG or DOJ. If we are ever found to
have   engaged  in  improper   practices,   we  could  be  subjected  to  civil,
administrative  or criminal  fines,  penalties  or  restitutionary  relief,  and
suspension  or  exclusion of the entity or  individuals  from  participation  in
federal and state healthcare programs.

     PATIENT INFORMATION AND PRIVACY.  HIPAA also mandates,  among other things,
the establishment of regulatory  standards addressing the electronic exchange of
health information, standards for the privacy and security of health information
maintained or exchanged  electronically,  and  standards  for  assigning  unique
health identifiers to healthcare providers. Sanctions for failure to comply with
HIPAA standards  include civil and criminal  penalties.  The Security  Standards
require  us  to  implement   certain   security   measures  to  protect  certain
individually   identifiable   health   information,   called   protected  health
information,  or PHI,  in  electronic  format.  The  Standards  for  Privacy  of
Individually  Identifiable Information restrict use and disclosure of PHI unless
patient authorization for such disclosures are obtained. These Privacy Standards
not  only  require  our  compliance  with  standards  restricting  the  use  and
disclosure of PHI, but also require us to obtain  satisfactory  assurances  that
any  business  associate  of ours  who has  access  to our  PHI  similarly  will
safeguard such PHI.

We have  evaluated  these  rules to  determine  the  effects of the rules on our
business, and we believe that we have taken the appropriate steps to ensure that
we will comply with these standards in all material respects by their respective
compliance deadlines.

OUR BUSINESS INVOLVES ENVIRONMENTAL RISKS THAT MAY RESULT IN LIABILITY.

     We are subject to a variety of local, state, federal and foreign government
regulations  relating to storage,  discharge,  handling,  emission,  generation,
manufacture and disposal of toxic, infectious or other hazardous substances used
to manufacture  our products.  If we fail to comply with these  regulations,  we
could be liable  for  damages,  penalties,  or other  forms of  censure  and our
business  could be  significantly  and adversely  affected.  We currently do not
carry  insurance  for  contamination  or injury  resulting  from the use of such
materials.

     Two of our marketed products, ProstaScint and Quadramet utilize radioactive
materials.  ProstaScint is not manufactured or shipped as a radioactive material
because the radioactive  component is not added until the product has arrived at
its final  destination  (a  radiopharmacy).  Laureate  Pharma,  our most  recent
contract  manufacturer of  ProstaScint,  holds a radioactive  materials  license
because such license is required for certain  release and stability tests of the
product.

     Quadramet  however,  is  manufactured  and  shipped  as  radioactive,   and
therefore,  the  manufacturing and distribution of this product must comply with
regulations  promulgated  by  the  U.S.  Nuclear  Regulatory  Commission.  BMSMI
manufacturers and distributes  Quadramet,  and is,  therefore,  subject to these
regulations.

                                      -20-



WE HAVE BEEN SUBJECT TO PATENT LITIGATION.
 
     On March 17, 2000, we were served with a complaint  filed against us in the
United  States  District  Court  for the  District  of New  Jersey  by M.  David
Goldenberg and Immunomedics,  Inc. (collectively  "Plaintiffs").  The litigation
claimed that our ProstaScint  product  infringes a patent  purportedly  owned by
Goldenberg and licensed to  Immunomedics.  We believe that  ProstaScint  did not
infringe this patent, and that the patent was invalid and unenforceable. In June
2004,  the U.S. Court of Appeals for the Federal  Circuit  affirmed the district
court's  grant  of  summary  judgment  of  no  literal  infringement.  Regarding
infringement  under the  doctrine of  equivalents,  however,  the U.S.  Court of
Appeals for the Federal Circuit  disagreed with the district court's  conclusion
that there was no issue of material fact and reversed the district court's grant
of summary  judgment on this point and remanded for further  proceedings  on the
issue.  In  September  2004,  we  settled  the patent  infringement  suit for an
undisclosed payment, without any admission of fault or liability.

We cannot  give any  assurance  that we will not become  subject  to  additional
patent litigation in the future, which could result in material  expenditures to
us.

OUR STOCK PRICE HAS BEEN AND MAY CONTINUE TO BE VOLATILE, AND YOUR INVESTMENT IN
OUR STOCK COULD DECLINE IN VALUE OR FLUCTUATE SIGNIFICANTLY.

     The market  prices  for  securities  of  biotechnology  and  pharmaceutical
companies have historically  been highly volatile,  and the market has from time
to time experienced significant price and volume fluctuations that are unrelated
to the operating  performance of particular  companies.  The market price of our
common stock has fluctuated  over a wide range and may continue to fluctuate for
various reasons,  including,  but not limited to,  announcements  concerning our
competitors or us regarding:

  o  results of clinical trials;

  o  technological innovations or new commercial products;

  o  changes  in  governmental  regulation  or  the  status  of  our  regulatory
     approvals or applications;

  o  changes in earnings;

  o  changes in health care policies and practices;

  o  developments or disputes concerning proprietary rights;

  o  litigation or public  concern as to safety of the our  potential  products;
     and

  o  changes in general market conditions.

     These  fluctuations  may be exaggerated if the trading volume of our common
stock  is low.  These  fluctuations  may or may  not be  based  upon  any of our
business or operating  results.  Our common stock may experience similar or even
more dramatic price and volume fluctuations which may continue indefinitely.

WE HAVE ADOPTED  VARIOUS  ANTI-TAKEOVER  PROVISIONS  WHICH MAY AFFECT THE MARKET
PRICE OF OUR COMMON STOCK AND PREVENT OR FRUSTRATE  ATTEMPTS BY OUR STOCKHOLDERS
TO REPLACE OR REMOVE OUR MANAGEMENT TEAM.

     Our Board of Directors has the  authority,  without  further  action by the
holders of common stock,  to issue from time to time, up to 5,400,000  shares of
preferred stock in one or more classes or series, and 

                                      -21-



to fix the rights and  preferences  of the  preferred  stock.  Pursuant to these
provisions, we have implemented a stockholder rights plan by which one preferred
stock  purchase  right is attached to each share of common stock,  as a means to
deter coercive  takeover tactics and to prevent an acquirer from gaining control
of us without some mechanism to secure a fair price for all of our  stockholders
if an acquisition was completed. These rights will be exercisable if a person or
group acquires  beneficial  ownership of 20% or more of our common stock and can
be made  exercisable  by action of our board of  directors  if a person or group
commences a tender offer which would result in such person or group beneficially
owning 20% or more of our common  stock.  Each right will  entitle the holder to
buy one  one-thousandth  of a share of a new series of our junior  participating
preferred stock for $20. If any person or group becomes the beneficial  owner of
20% or more of our common stock (with  certain  limited  exceptions),  then each
right not owned by the 20% stockholder  will entitle its holder to purchase,  at
the right's then current exercise price,  common shares having a market value of
twice the  exercise  price.  In  addition,  if after any person has become a 20%
stockholder,  we  are  involved  in  a  merger  or  other  business  combination
transaction with another person,  each right will entitle its holder (other than
the 20%  stockholder) to purchase,  at the right's then current  exercise price,
common shares of the acquiring  company having a value of twice the right's then
current exercise price.

     We are subject to  provisions of Delaware  corporate law which,  subject to
certain exceptions, will prohibit us from engaging in any "business combination"
with a person who, together with affiliates and associates,  owns 15% or more of
our common stock for a period of three years  following the date that the person
came to own 15% or more of our common stock unless the business  combination  is
approved in a prescribed manner.

     These  provisions  of the  stockholder  rights  plan,  our  certificate  of
incorporation, and of Delaware law may have the effect of delaying, deterring or
preventing a change in control of Cytogen,  may  discourage  bids for our common
stock at a premium over market price and may adversely  affect the market price,
and the  voting  and other  rights  of the  holders,  of our  common  stock.  In
addition,  these  provisions  make it more  difficult  to  replace or remove our
current  management team in the event our stockholders  believe this would be in
the best interest of the Company and our stockholders.

THE LIQUIDITY OF OUR COMMON STOCK COULD BE ADVERSELY AFFECTED IF WE ARE DELISTED
FROM THE NASDAQ NATIONAL MARKET.

     In the event  that we are  unable  maintain  compliance  with all  relevant
Nasdaq  Listing  Standards,  our securities may be subject to delisting from the
Nasdaq National Market.  If such delisting  occurs,  the market price and market
liquidity of our common stock may be adversely affected.

     Alternatively,  if faced with such delisting,  we may submit an application
to transfer the listing of our common stock to the Nasdaq SmallCap  Market.  The
Nasdaq  SmallCap  Market  also has a $1.00  minimum  bid price  requirement.  On
November  3, 2004,  the  closing  sale price of our common  stock as reported by
Nasdaq was $10.26.

     If our common  stock is  delisted  by Nasdaq,  our  common  stock  would be
eligible  to trade on the OTC  Bulletin  Board  maintained  by  Nasdaq,  another
over-the-counter  quotation  system, or on the pink sheets where an investor may
find it more  difficult to dispose of or obtain  accurate  quotations  as to the
market value of our common  stock.  In  addition,  we would be subject to a rule
promulgated by the Securities and Exchange  Commission  that, if we fail to meet
criteria  set forth in such  rule,  imposes  various  practice  requirements  on
broker-dealers  who sell  securities  governed by the rule to persons other than
established  customers and  accredited  investors.  Consequently,  such rule may
deter  broker-dealers  from recommending or selling our common stock,  which may
further affect the liquidity of our common stock.

                                      -22-



     Delisting  from Nasdaq would make  trading our common stock more  difficult
for investors,  potentially  leading to further  declines in our share price. It
would also make it more difficult for us to raise additional  capital.  Further,
if we are delisted,  we would also incur  additional  costs under state blue sky
laws in connection with any sales of our securities.  These  requirements  could
severely  limit the market  liquidity of our common stock and the ability of our
shareholders to sell our common stock in the secondary market.

A LARGE NUMBER OF OUR SHARES ARE  ELIGIBLE  FOR FUTURE SALE WHICH MAY  ADVERSELY
IMPACT THE MARKET PRICE OF OUR COMMON STOCK.

     A large  number of  shares of our  common  stock are  already  outstanding,
issuable upon exercise of options and warrants,  or the  achievement  of certain
milestones  under  previously  completed  acquisitions  and may be eligible  for
resale.  This  availability of a significant  number of additional shares of our
common stock for future sale and issuance  could depress the price of our common
stock.

BECAUSE WE DO NOT INTEND TO PAY,  AND HAVE NOT PAID,  ANY CASH  DIVIDENDS ON OUR
SHARES OF COMMON STOCK, OUR STOCKHOLDERS WILL NOT BE ABLE TO RECEIVE A RETURN ON
THEIR SHARES UNLESS THE VALUE OF OUR SHARES APPRECIATES AND THEY SELL THEM.

     We have never paid or declared  any cash  dividends  on our common stock or
other  securities  and  intend to retain  any future  earnings  to  finance  the
development and expansion of our business.  We do not anticipate paying any cash
dividends  on  our  common  stock  in the  foreseeable  future.  Therefore,  our
stockholders  will not be able to  receive a return on their  shares  unless the
value of our shares appreciates and they sell them.

                SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

     This prospectus contains  forward-looking  statements within the meaning of
the  Private  Securities  Litigation  Reform Act of 1995 and  Section 21E of the
Securities Exchange Act of 1934, as amended.  These  forward-looking  statements
regarding   future   events  and  our  future   results  are  based  on  current
expectations,   estimates,  forecasts,  and  projections  and  the  beliefs  and
assumptions of our management  including,  without limitation,  our expectations
regarding results of operations,  selling,  general and administrative expenses,
research and  development  expenses and the  sufficiency  of our cash for future
operations.   Forward-looking  statements  may  be  identified  by  the  use  of
forward-looking   terminology  such  as  "may,"  "will,"  "expect,"  "estimate,"
"anticipate,"  "continue,"  or similar  terms,  variations  of such terms or the
negative of those terms.  These  forward-looking  statements  include statements
regarding our agreements with our collaborative partners, our intent to hold our
investments  until  maturity,  additional  funding  of  the  PSMA  technologies,
potential charges resulting from the closure of AxCell  BioSciences,  growth and
market penetration for Quadramet and ProstaScint,  revenues,  if any, from NMP22
BladderChek  and from our joint  venture with  Progenics  Pharmaceuticals  Inc.,
increased  expenses  resulting  from our sales  force and  marketing  expansion,
including  sales and marketing  expenses for Quadramet,  the  sufficiency of our
capital resources, our need for additional capital and other statements included
in  this  prospectus  that  are  not  historical  facts.  Such   forward-looking
statements  involve  a number  of risks  and  uncertainties  and  investors  are
cautioned not to put any undue  reliance on any  forward-looking  statement.  We
cannot  guarantee  that  we will  actually  achieve  the  plans,  intentions  or
expectations  disclosed  in any such  forward-looking  statements.  Factors that
could cause actual results to differ materially,  include,  market acceptance of
our products, the results of our clinical trials, our ability to hire and retain
employees,  economic and market conditions  generally,  our receipt of requisite
regulatory  approvals  for our products and product  candidates,  the  continued
cooperation of our marketing and other collaborative and strategic partners, our
ability to protect our  intellectual  property,  and the other risks  identified
herein under the caption "Risk Factors."

                                      -23-



     Any  forward-looking  statements  made by us do not reflect  the  potential
impact of any future  acquisitions,  mergers,  dispositions,  joint  ventures or
investments  we may make.  You should  read and  interpret  any  forward-looking
statements together with the following documents:

     o  our most recent Annual Report on Form 10-K;

     o  our most recent quarterly report of Form 10-Q;

     o  the risk factors contained  in this prospectus  under the caption  "Risk
        Factors"; and

     o  our other filings with the Securities and Exchange Commission.

     Any  forward-looking  statement  speaks  only as of the date on which  that
statement is made. We will not update any  forward-looking  statement to reflect
events or  circumstances  that occur after the date on which such  statement  is
made.

                                 USE OF PROCEEDS

     We will  receive all of the net  proceeds  from the sale of our  securities
registered under the registration statement of which this prospectus is a part.

     Unless the  applicable  prospectus  supplement  states  otherwise,  we will
retain broad  discretion in the allocation of the net proceeds of this offering.
We  currently  intend to use the net  proceeds of this and any future  issuances
for:

     o  expansion of our sales and marketing capabilities;

     o  research and development on existing or new products;

     o  potential  product   acquisitions   and/or  potential   acquisitions  of
        complementary businesses; and

     o  other general corporate purposes,  including principally working capital
        and capital expenditures.

     We have not  determined  the amount of net  proceeds to be used for each of
the specific purposes indicated.  The amounts and timing of the expenditures may
vary  significantly  depending on numerous factors,  such as the progress of our
research and  development  efforts,  technological  advances and the competitive
environment for our products.  Accordingly, we will have broad discretion to use
the  proceeds  as we see fit.  Pending  such  uses,  we intend to invest the net
proceeds in interest-bearing, investment grade securities.

        RATIO OF EARNINGS TO FIXED CHARGES AND PREFERRED STOCK DIVIDENDS

     The following table sets forth our dollar coverage deficiency. The ratio of
earnings to fixed charges is not disclosed since it is a negative number in each
year and period shown below.  Any time we offer debt securities pursuant to this
prospectus, we will provide an updated table setting forth our ratio of earnings
to fixed charges on a historical basis in the applicable prospectus  supplement,
if  required.  Any time we offer  shares of  preferred  stock  pursuant  to this
prospectus,  we will provide a table setting  forth our ratio of combined  fixed
charges and preferred stock dividends to earnings, if required.

                                      -24-





                                                                                               For the Nine
                                                                                               Months Ended
                                                     Year Ended December 31,                   September 30,
                                    1999         2000        2001         2002       2003          2004
                                    ----         ----        ----         ----       ----          ----
                                                (All Amounts in Thousands)
                                                                                 
Ratio of Earnings to
Fixed Charges...............         --           --          --           --         --           --

Earnings Available to
Cover Fixed Charges
(Deficiency)................      $(1,973)    $(24,609)    $(13,203)   $(15,699)   $(10,246)    $(14,262)



                          DESCRIPTION OF DEBT SECURITIES

     We may offer senior debt securities,  subordinated debt securities or both.
Senior debt  securities and  subordinated  debt  securities will be issued under
separate  indentures  between  us, as issuer,  and the trustee  identified  in a
prospectus supplement. Further information regarding the trustee may be provided
in the prospectus supplement. The form for each type of indenture is filed as an
exhibit to the registration statement of which this prospectus is a part.

     The prospectus  supplement  will describe the particular  terms of any debt
securities  we may offer and may  supplement  the terms  summarized  below.  The
following  summaries of the debt  securities and the indentures are not complete
and may be  modified by the  description  of  particular  debt  securities  in a
prospectus supplement.  We urge you to read the indenture filed as an exhibit to
the  registration  statement  that  relates  to  debt  securities  offered  in a
prospectus  supplement and the  description of the additional  terms of the debt
securities included in the prospectus supplement.

GENERAL

     The indentures  provide that we may issue an unlimited  principal amount of
debt securities in separate series. We may specify a maximum aggregate principal
amount for the debt  securities  of any series.  The debt  securities  will have
maturities  that  are  set  forth  in the  prospectus  supplement.  Senior  debt
securities  will be  unsecured  and  unsubordinated  obligations  and will  rank
equally with all our other unsecured and unsubordinated debt.  Subordinated debt
securities  will  be  unsecured  obligations  and  may be paid by us only if all
payments due under our senior  indebtedness,  including any  outstanding  senior
debt securities, have been made.

     The  indentures  might not limit the amount of other debt that we may incur
and might not contain financial or similar restrictive covenants. The indentures
might not contain any provision to protect  holders of debt  securities  against
transactions  that may cause a sudden or dramatic  decline in our ability to pay
our debt.

     The prospectus  supplement  will describe the debt securities and the price
or  prices at which we will  offer the debt  securities.  The  description  will
include:

  o  the title of the debt securities;

  o  any limit on the aggregate  principal  amount of the debt securities or the
     series of which they are a part;

                                      -25-



  o  the person to whom any  interest  on a debt  security of the series will be
     paid;

  o  the date or dates on which we must repay the principal;

  o  the rate or rates at which the debt securities will bear interest;

  o  the date or dates from which interest will accrue and the dates on which we
     must pay interest;

  o  the place or places  where we must pay the  principal  and any  premium  or
     interest on the debt securities;

  o  the terms and  conditions on which we may redeem any debt  security,  if at
     all;

  o  any obligation to redeem or purchase any debt  securities and the terms and
     conditions on which we must do so;

  o  the denominations in which we may issue the debt securities;

  o  the manner in which we will  determine  the amount of  principal  of or any
     premium or interest on the debt securities;

  o  the  currency  in which we will pay the  principal  of and any  premium  or
     interest on the debt securities;

  o  if  applicable,  that the debt  securities  are defeasible and the terms of
     such defeasance;

  o  if applicable,  the terms of any right to convert debt securities  into, or
     exchange debt securities for, shares of common stock or other securities or
     property;

  o  whether we will issue the debt securities in the form of one or more global
     securities  and,  if  so,  the  respective   depositaries  for  the  global
     securities and the terms of the global securities;

  o  the  subordination  provisions  that will  apply to any  subordinated  debt
     securities;

  o  any addition to or change in the events of default  applicable  to the debt
     securities  and any change in the right of the  trustee  or the  holders to
     declare the principal amount of any of the debt securities due and payable;

  o  any addition to or change in the covenants in the indentures; and

  o  any other terms of the debt securities not inconsistent with the applicable
     indenture.

     We may sell the debt  securities  at a  substantial  discount  below  their
stated principal amount. We will describe U.S. federal income tax considerations
applicable  to  debt  securities  sold  at an  original  issue  discount  in the
prospectus supplement.  An original issue discount security is any debt security
sold for less than its face  value and which  provides  that the  holder  cannot
receive  the  full  face  value  if  maturity  is  accelerated.  The  prospectus
supplement  relating to any original issue discount securities will describe the
particular  provisions  relating  to  acceleration  of  the  maturity  upon  the
occurrence  of an  event  of  default.  In  addition,  we will  describe  in the
prospectus supplement U.S. federal income tax or other considerations applicable
to any debt  securities  that are  denominated  in a currency or unit other than
U.S. dollars.

                                      -26-



CONVERSION AND EXCHANGE RIGHTS

     The prospectus supplement will describe, if applicable,  the terms on which
you may convert debt  securities into or exchange them for common stock or other
securities or property. The conversion or exchange may be mandatory or may be at
your option. The prospectus supplement will describe how the number of shares of
common stock or other  securities or property to be received upon  conversion or
exchange would be calculated.

SUBORDINATION OF SUBORDINATED DEBT SECURITIES

     The indebtedness underlying the subordinated debt securities may be paid by
us only if all  payments  due  under  our  senior  indebtedness,  including  any
outstanding senior debt securities,  have been made. If we distribute our assets
to creditors upon any dissolution,  winding-up, liquidation or reorganization or
in bankruptcy,  insolvency,  receivership or similar proceedings,  we must first
pay all  amounts due or to become due on all senior  indebtedness  before we pay
the  principal  of,  or any  premium  or  interest  on,  the  subordinated  debt
securities.  In the event  the  subordinated  debt  securities  are  accelerated
because of an event of default,  we may not make any payment on the subordinated
debt securities  until we have paid all senior  indebtedness or the acceleration
is rescinded. If the payment of subordinated debt securities accelerates because
of an event of default,  we must promptly notify holders of senior  indebtedness
of the acceleration.

     If we experience a bankruptcy,  dissolution or  reorganization,  holders of
senior indebtedness may receive more, ratably,  and holders of subordinated debt
securities may receive less,  ratably,  than our other creditors.  The indenture
for  subordinated  debt securities may not limit our ability to incur additional
senior indebtedness.

FORM, EXCHANGE AND TRANSFER

     We will issue debt securities in the form of global  securities or in fully
registered  form,  without  coupons,  in  denominations  of $1,000 and  integral
multiples  thereof.  The holder of a debt security in fully  registered form may
elect,  subject to the terms of the applicable  indenture,  to exchange them for
other debt securities of the same series of any authorized  denomination  and of
similar terms and aggregate principal amount.

     Holders of debt  securities in fully  registered  form may present them for
exchange as provided  above or for  registration  of transfer,  duly endorsed or
with the form of transfer duly executed,  at the office of the transfer agent we
designate  for  that  purpose.  We will  not  impose a  service  charge  for any
registration  of transfer or exchange of debt  securities,  but we may require a
payment  sufficient  to cover any tax or other  governmental  charge  payable in
connection with the transfer or exchange. We will name the transfer agent in the
prospectus  supplement.  We may designate  additional transfer agents or rescind
the  designation of any transfer agent or approve a change in the office through
which any transfer  agent acts,  but we must  maintain a transfer  agent in each
place where we will make payment on debt securities.

     If we  redeem  the debt  securities,  we will  not be  required  to  issue,
register the transfer of or exchange any debt security during a specified period
prior to mailing a notice of  redemption.  We are not  required to register  the
transfer of or exchange of any debt security selected for redemption, except the
unredeemed portion of the debt security being redeemed.

PAYMENT AND PAYING AGENTS

     We will pay principal and any premium or interest on a debt security to the
person in whose name the debt security is registered at the close of business on
the regular record date for such interest.

                                     -27-



     We will pay principal and any premium or interest on the debt securities at
the office of our  designated  paying agent.  Unless the  prospectus  supplement
indicates  otherwise,  the  corporate  trust  office of the trustee  will be the
paying agent for the debt securities.

     Any  other  paying  agents  we  designate  for  the  debt  securities  of a
particular series will be named in the prospectus  supplement.  We may designate
additional paying agents, rescind the designation of any paying agent or approve
a change in the office through which any paying agent acts, but we must maintain
a paying agent in each place of payment for the debt securities.

     The paying  agent will  return to us all money we pay to it for the payment
of the  principal,  premium  or  interest  on any  debt  security  that  remains
unclaimed for a specified period. Thereafter, the holder may look only to us for
payment, as an unsecured general creditor.

CONSOLIDATION, MERGER AND SALE OF ASSETS

     Under  the  terms  of the  indentures,  so  long as any  securities  remain
outstanding, we may not consolidate or enter into a share exchange with or merge
into any  other  person,  in a  transaction  in  which we are not the  surviving
corporation,  or sell,  convey,  transfer  or lease our  properties  and  assets
substantially as an entirety to any person, unless:

  o  the successor  assumes our  obligations  under the debt  securities and the
     indentures; and

  o  we meet the other conditions described in the indentures.

EVENTS OF DEFAULT

Each of the following  will  constitute an event of default under each indenture
with respect to any series of debt securities:

  o  failure to pay the principal of or any premium on any debt security of that
     series when due;

  o  failure to pay any  interest on any debt  security of that series when due,
     for more than a specified number of days past the due date;

  o  failure to deposit any sinking fund payment with respect to debt securities
     of that series when due;

  o  failure  to  perform  any  covenant  or  agreement  in the  indenture  that
     continues  for a  specified  number of days after  written  notice has been
     given by the trustee or the holders of a specified  percentage in aggregate
     principal amount of the debt securities of that series;

  o  certain events of bankruptcy, insolvency or reorganization; and

  o  any other event of default specified in the prospectus supplement.

     If an event of default occurs and continues,  either the trustee or holders
of a specified  percentage  in  aggregate  principal  amount of the  outstanding
securities  of  that  series  may  declare  the  principal  amount  of the  debt
securities of that series to be  immediately  due and payable.  The holders of a
majority in aggregate  principal  amount of the  outstanding  securities of that
series may rescind and annul the  acceleration  if all events of default,  other
than the nonpayment of accelerated principal, have been cured or waived.

                                     -28-



     Except for its duties in case of an event of default,  the trustee will not
be obligated to exercise any of its rights or powers at the request or direction
of any of the holders,  unless the holders  have offered the trustee  reasonable
indemnity.  If they provide this  indemnification,  the holders of a majority in
aggregate  principal  amount of the  outstanding  securities  of any  series may
direct the time,  method and place of conducting  any  proceeding for any remedy
available  to the  trustee or  exercising  any trust or power  conferred  on the
trustee with respect to the debt securities of that series.

     No holder of a debt  security of any series may  institute  any  proceeding
with respect to an indenture, or for the appointment of a receiver or a trustee,
or for any other remedy, unless:

  o  the holder has previously  given the trustee written notice of a continuing
     event of default;

  o  the holders of a specified  percentage in aggregate principal amount of the
     outstanding  securities of that series have made a written request upon the
     trustee, and have offered reasonable indemnity to the trustee, to institute
     the proceeding;

  o  the trustee has failed to institute the proceeding  for a specified  period
     of time after its receipt of the notification; and

  o  the trustee  has not  received a  direction  inconsistent  with the request
     within  a  specified  number  of  days  from  the  holders  of a  specified
     percentage in aggregate  principal amount of the outstanding  securities of
     that series.

MODIFICATION AND WAIVER

We and the  trustee may change an  indenture  without the consent of any holders
with respect to specific matters, including:

  o  to fix any ambiguity, defect or inconsistency in the indenture; and

  o  to change anything that does not materially  adversely affect the interests
     of any holder of debt securities of any series.

     In addition,  under an indenture, the rights of holders of a series of debt
securities may be changed by us and the trustee with the written  consent of the
holders of at least a majority in aggregate  principal amount of the outstanding
debt  securities of that series.  However,  we and the trustee may only make the
following  changes  with the  consent  of the  holder  of any  outstanding  debt
securities affected:

  o  extending the fixed maturity of the debt securities;

  o  reducing the principal  amount,  reducing the rate of or extending the time
     of payment of interest, or any premium payable upon the redemption,  of the
     debt securities; or

  o  reducing  the  percentage  of debt  securities  the  holders  of which  are
     required to consent to any amendment.

     The  holders of a majority  in  principal  amount of the  outstanding  debt
securities  of any series may waive any past default  under the  indenture  with
respect to debt  securities  of that series,  except a default in the payment of
principal, premium or interest on any debt security of that series or in respect
of a covenant or provision of the indenture that cannot be amended  without each
holder's consent.

     Except in limited  circumstances,  we may set any day as a record  date for
the purpose of  determining  the holders of outstanding  debt  securities of any
series entitled to give or take any direction,

                                      -29-



notice,  consent,  waiver or other  action  under  the  indentures.  In  limited
circumstances,  the trustee may set a record date. To be  effective,  the action
must be  taken  by  holders  of the  requisite  principal  amount  of such  debt
securities within a specified period following the record date.

DEFEASANCE

     To the extent stated in the  prospectus  supplement,  we may elect to apply
the  provisions  in  an  indenture  relating  to  defeasance  and  discharge  of
indebtedness,  or to defeasance of restrictive covenants, to the debt securities
of  any  series.   The  indentures   provide  that,  upon  satisfaction  of  the
requirements  described below, we may terminate all of our obligations under the
debt  securities  of any series  and the  applicable  indenture,  known as legal
defeasance, other than our obligation:

  o  to  maintain a registrar  and paying  agents and hold monies for payment in
     trust;

  o  to register the transfer or exchange of the debt securities; and

  o  to replace mutilated, destroyed, lost or stolen debt securities.

     In addition, we may terminate our obligation to comply with any restrictive
covenants  applicable  to debt  securities  of any  series,  known  as  covenant
defeasance.

     We may  exercise  our legal  defeasance  option even if we have  previously
exercised  our covenant  defeasance  option.  If we exercise  either  defeasance
option, payment of the applicable debt securities may not be accelerated because
of the occurrence of an event of default.

     To exercise either  defeasance  option as to debt securities of any series,
we must irrevocably  deposit in trust with the trustee money and/or  obligations
backed by the full faith and credit of the United States that will provide money
in an amount  sufficient in the written opinion of a nationally  recognized firm
of independent public accountants to pay the principal of, premium,  if any, and
each installment of interest on the debt securities.  We may only establish this
trust if, among other things:

  o  no event of default shall have occurred or be continuing;

  o  in the  case of legal  defeasance,  we have  delivered  to the  trustee  an
     opinion of counsel to the effect that we have  received  from, or there has
     been published by, the Internal  Revenue Service a ruling or there has been
     a change in law, which in the opinion of our counsel, provides that holders
     of the debt  securities  will not recognize gain or loss for federal income
     tax purposes as a result of such deposit, defeasance and discharge and will
     be subject to federal income tax on the same amount, in the same manner and
     at the same times as would have been the case if such  deposit,  defeasance
     and discharge had not occurred;

  o  in the case of covenant  defeasance,  we have  delivered  to the trustee an
     opinion of counsel to the effect  that the  holders of the debt  securities
     will not recognize gain or loss for federal income tax purposes as a result
     of such  deposit,  defeasance  and discharge and will be subject to federal
     income tax on the same amount,  in the same manner and at the same times as
     would have been the case if such deposit,  defeasance and discharge had not
     occurred; and

  o  we satisfy other customary conditions precedent described in the applicable
     indenture.

                                      -30-



OWNERSHIP

     We may treat the person in whose name a debt  security is registered as the
absolute  owner,  whether  or not such debt  security  may be  overdue,  for the
purpose of making payment and for all other purposes.

                          DESCRIPTION OF CAPITAL STOCK

     The total  number of shares of all classes of stock that we have  authority
to issue is  30,400,000,  consisting of 25,000,000  shares of common stock,  par
value  $0.01 per  share,  and  5,400,000 shares  of preferred  stock,  par value
$0.01 per  share.  We had  15,436,501 shares  of common stock,  and no shares of
preferred stock, outstanding as of November 1, 2004, which number of shares: (i)
includes  an  aggregate  of 241  shares  of  common  stock to be issued to prior
holders of  securities  of CytoRad  Incorporated  and  Cellcor,  Inc.,  which we
acquired in 1995, upon each such holders respective exchange of such securities;
(ii)  excludes  50,000  shares  of  common  stock  previously  issued  by us and
currently held in escrow pending release,  upon certain conditions,  to Advanced
Magnetics, who currently maintains voting control of such securities;  and (iii)
excludes 23,833 shares  previously  issued by us and currently held for issuance
by the  custodian  of our  Employee  Stock  Purchase  Plan  to the  participants
thereunder, in the event they elect to purchase such shares.

     In the discussion that follows,  we have summarized  selected provisions of
our certificate of  incorporation  and our bylaws relating to our capital stock.
You should read our  certificate  of  incorporation  and bylaws as  currently in
effect for more details regarding the provisions we describe below and for other
provisions that may be important to you. We have filed copies of those documents
with the SEC,  and  they  are  incorporated  by  reference  as  exhibits  to the
registration statement. Please read "Where You Can Find More Information."

COMMON STOCK

     The  holders  of  common  stock are  entitled  to one vote per share on all
matters  voted on by our  stockholders,  including  the  election of  directors,
except as may, in the future,  be  provided  in any  resolutions  adopted by our
board of  directors  with respect to any series of  preferred  stock.  Except as
otherwise  required by law or provided in any resolution adopted by our board of
directors with respect to any series of preferred  stock,  the holders of shares
of common  stock  exclusively  possess  all  voting  power of our  stockholders.
Subject to any preferential  rights of any then outstanding  series of preferred
stock,  the holders of common  stock are  entitled to those  dividends as may be
declared  from time to time by our board of directors  from funds  available for
dividends  and,  upon  liquidation,  are entitled to receive pro rata all of our
assets available for distribution to our stockholders.

PREFERRED STOCK

     Our board of directors  is  authorized  to establish  one or more series of
preferred stock and to determine, with respect to any series of preferred stock,
the  powers,  designation,  preferences  and  rights  of  each  series  and  the
qualifications, limitations or restrictions of each series, including:

  o  the designation of the series;

  o  the number of shares of the  series,  which  number the board of  directors
     may,  except where otherwise  provided in the preferred stock  designation,
     increase  or  decrease,  but not below the number of shares of that  series
     then outstanding;

  o  whether  dividends,  if any, will be cumulative  or  noncumulative  and the
     dividend rate and the

                                      -31-



     preferences, if any, of the series;

  o  the dates on which dividends, if any, will be payable;

  o  the  redemption  rights  and price or  prices,  if any,  for  shares of the
     series;

  o  the terms and  amounts of any sinking  fund  provided  for the  purchase or
     redemption of shares of the series;

  o  the  amounts  payable  on, and the  preferences,  if any,  of shares of the
     series  in  the  event  of  any  voluntary  or   involuntary   liquidation,
     dissolution or winding up of our affairs;

  o  whether the shares of the series will be convertible  into or  exchangeable
     for shares of any other  class or  series,  or any other  security,  of our
     company or any other  corporation,  and, if so, the  specification  of that
     class or series or that other security, the conversion or exchange price or
     prices or rate or rates, any adjustments to those prices or rates, the date
     or dates as of which such shares will be  convertible or  exchangeable  and
     all other terms and conditions of the conversion or exchange;

  o  restrictions on the issuance of shares of the same series,  or of any other
     class or series; and

  o  the voting rights, if any, of the holders of shares of any series.

     The  prospectus  supplement  relating to any series of  preferred  stock we
offer will include  specific terms relating to the offering.  The description of
the terms of the  preferred  stock to be set forth in an  applicable  prospectus
supplement  will not be  complete  and will be subject to and  qualified  by the
certificate of designation relating to the applicable series of preferred stock.
You should read that  document for  provisions  that may be important to you. We
will include that  document as an exhibit to a filing with the SEC in connection
with an offering of preferred stock.

     The  authorized  shares  of  preferred  stock,  as well as shares of common
stock,  are available for issuance  without further action by our  stockholders,
unless  stockholder  action is  required  by the rules of any stock  exchange or
automated  quotation system on which our securities are listed or traded. If the
approval  of our  stockholders  is not  required  for the  issuance of shares of
preferred  stock or common  stock,  the board of directors  may determine not to
seek stockholder approval.

RIGHTS PLAN

     In June 1998,  we adopted a rights plan under which our board of  directors
declared a dividend of one preferred  stock purchase right for each  outstanding
share of our common stock held of record as of the close of business on June 30,
1998.   Each  right   initially   entitles  a  stockholder  to  purchase  a  one
one-thousandth  fraction  of a share  of  Preferred  Stock  --  Series  C Junior
Participating  Participating  Preferred  Stock for $20.  Each such fraction of a
share of preferred stock has terms designed to make it essentially equivalent to
one share of common stock. The rights will become  exercisable only in the event
a person or group acquires 20% or more of our common stock or commences a tender
or exchange offer which,  if  consummated,  would result in that person or group
owning  20% of our common  stock.  Prior to such an event,  the  rights  will be
evidenced by and traded in tandem with the common stock.

     If a person or group  acquires a 20% or larger  position in  Cytogen,  each
right (except those held by the acquiring party) will then entitle its holder to
purchase  fractional shares of preferred stock having twice the value of the $20
exercise price, with each fractional  preferred share valued at the market price
of the common  stock.  Also, if following an  acquisition  of 20% or more of our
common  stock,  Cytogen is

                                      -32-



acquired  by that  person  or group in a merger  or other  business  combination
transaction,  each right would then entitle its holder to purchase  common stock
of the acquiring company having a value of twice exercise price. The effect will
be to entitle our  stockholders to buy stock in the acquiring  company at 50% of
its market price.

     We may  redeem the rights at $0.01 per right at any time on or prior to the
acquisition  of 20% or  more  of our  common  stock  by a  person  or  group  or
commencement of a tender offer for such 20% ownership. The rights expire on June
19, 2008.

OUTSTANDING WARRANTS

     At  November 1, 2004,  we had  outstanding  warrants to purchase  1,940,619
shares of our common stock.  These warrants expire at various times through July
2008, and have a weighted average exercise price of $11.26 per share.

SPECIAL PROVISIONS OF OUR CHARTER, BYLAWS AND DELAWARE LAW

     The following  charter and bylaw  provisions and provisions of Delaware law
may have the effect of delaying, deterring or preventing a change of control.

AUTHORIZATION  OF  PREFERRED  STOCK.  As noted  above,  our board of  directors,
without  stockholder  approval,  has the  authority  under  our  certificate  of
incorporation to issue preferred stock with rights superior to the rights of the
holders of our common stock. As a result, preferred stock:

  o  could be issued quickly and easily;

  o  could adversely affect the rights of holders of our common stock; and

  o  could be  issued  with  terms  calculated  to delay or  prevent a change of
     control or make removal of management more difficult.

STOCKHOLDER MEETINGS AND WRITTEN CONSENT. Under our bylaws, a special meeting of
the stockholders may be called by:

  o  the chairman  of the board, the  president or by resolution of the board of
     directors; or

  o  the president or corporate  secretary upon the written  request of not less
     than 50% in interest of the stockholders entitled to vote.

REQUIREMENTS FOR ADVANCE NOTIFICATION OF STOCKHOLDER  NOMINATIONS AND PROPOSALS.
Our bylaws  establish  advance  notice  procedures  with respect to  stockholder
proposals and the nomination of candidates for election as directors, other than
nominations made by the board of directors or its committees.

INDEMNIFICATION.  Delaware  law  authorizes  Delaware  corporations  to limit or
eliminate the personal liability of directors for monetary damages for breach of
a director's fiduciary duty of care. The duty of care requires that, when acting
on behalf of the  corporation,  directors  must  exercise an  informed  business
judgment based on all material information  reasonably available to them. Absent
the limitations  authorized by Delaware law, directors of Delaware  corporations
are  accountable  to those  corporations  and their  stockholders  for  monetary
damages for conduct  constituting gross negligence in the exercise of their duty
of care. Delaware law enables Delaware corporations to limit available relief to
equitable  remedies  such  as  injunction  or  rescission.  Our  certificate  of
incorporation limits the liability of our directors to us or our stockholders to
the  fullest  extent  Delaware  law  permits,  and no  member  of our  board  is
personally

                                      -33-



liable for  monetary  damages  for breach of the  member's  fiduciary  duty as a
director, except for liability:

  o  for  any  breach  of a  board  member's  duty  of  loyalty  to  us  or  our
     stockholders;

  o  for  acts or  omissions  not in good  faith or  which  involve  intentional
     misconduct or a knowing violation of law;

  o  for  unlawful  payments of  dividends  or  unlawful  stock  repurchases  or
     redemptions as provided in Section 174 of the Delaware General  Corporation
     Law; or

  o  for any  transaction  from which the member  derived an  improper  personal
     benefit.

     This provision may discourage  derivative  litigation against our directors
and may  discourage  or deter our  stockholders  or  management  from bringing a
lawsuit against our directors for breach of their duty of care, even though such
an  action,   if  successful,   might   otherwise  have  benefited  us  and  our
stockholders.  Our bylaws provide  indemnification to our officers and directors
and other specified persons with respect to their conduct in various capacities.

TRANSFER AGENT OR REGISTRAR

American  Stock  Transfer & Trust Company is the transfer agent and registrar of
our common stock.

                             DESCRIPTION OF WARRANTS

We may issue  warrants to purchase  debt  securities,  preferred  stock,  common
stock,  or units.  We may issue  warrants  independently  or together with other
securities.  Warrants sold with other  securities may be attached to or separate
from the  other  securities.  We will  issue  each  series of  warrants  under a
separate warrant  agreement  between us and a warrant agent that we will name in
the prospectus supplement. We will describe additional terms of the warrants and
the applicable warrant agreements in the applicable prospectus supplement.

GENERAL

     If warrants are offered, the prospectus  supplement relating to a series of
warrants will include the specific terms of the warrants, including:

  o  the offering price;

  o  the title of the warrants;

  o  the aggregate number of warrants offered;

  o  the dates or periods during which the warrants can be exercised;

  o  whether the warrants will be issued in individual  certificates  to holders
     or in the form of  global  securities  held by a  depositary  on  behalf of
     holders;

  o  the  designation  and terms of any  securities  with which the warrants are
     issued;

  o  if the warrants are issued as a unit with another  security,  the date,  if
     any,  on and  after  which the  warrants  and the  other  security  will be
     separately transferable;

                                      -34-



  o  if the exercise price is not payable in U.S. dollars, the foreign currency,
     currency  unit or  composite  currency  in  which  the  exercise  price  is
     denominated;

  o  any terms,  procedures  and  limitations  relating to the  transferability,
     exchange or exercise of the warrants;

  o  any special tax implications of the warrants or their exercise;

  o  any antidilution provisions of the warrants;

  o  any redemption or call provisions applicable to the warrants; and

  o  any other terms of the warrants.

TRANSFERS AND EXCHANGES

     A holder  will be able to  exchange  warrant  certificates  for new warrant
certificates  of  different  denominations,  or to  transfer  warrants,  at  the
corporate trust office of the warrant agent or any other office indicated in the
prospectus supplement.  Prior to exercise, holders of warrants will have none of
the rights of holders of the underlying securities.

EXERCISE

     Holders  will be able to exercise  warrants  up to 5:00 P.M.  New York City
time on the date set forth in the prospectus supplement as the expiration date.

     After  this  time,  unless  we  have  extended  the  expiration  date,  the
unexercised warrants will be void.

     Subject to any  restrictions  and additional  requirements  that may be set
forth in a  prospectus  supplement,  holders of warrants  may  exercise  them by
delivering to the warrant agent at its corporate trust office the following:

  o  warrant certificates properly completed; and

  o  payment of the exercise price.

     As soon as practicable after the delivery, we will issue and deliver to the
indicated holder the securities  purchasable upon exercise. If a holder does not
exercise all the warrants represented by a particular certificate,  we will also
issue a new certificate for the remaining number of warrants.

NO RIGHTS OF SECURITY HOLDER PRIOR TO EXERCISE

     Prior to the exercise of their warrants,  holders of warrants will not have
any of the rights of holders of the securities  purchasable upon the exercise of
the warrants, and will not be entitled to:

  o  in the case of warrants to purchase debt securities,  payments of principal
     of,  premium,  if  any,  or  interest,  if  any,  on  the  debt  securities
     purchasable upon exercise; or

  o  in the case of warrants to purchase equity securities, the right to vote or
     to receive  dividend  payments or similar  distributions  on the securities
     purchasable upon exercise.

                                      -35-



ENFORCEABILITY OF RIGHTS BY HOLDERS OF WARRANTS

     Each warrant agent will act solely as our agent under the relevant  warrant
agreement and will not assume any obligation or  relationship of agency or trust
for any  warrantholder.  A single bank or trust company may act as warrant agent
for more  than one  issue of  warrants.  A  warrant  agent  will have no duty or
responsibility  if we default in performing our  obligations  under the relevant
warrant  agreement or warrant,  including any duty or responsibility to initiate
any legal proceedings or to make any demand upon us.

TITLE

     We and the warrant  agents and any of our  respective  agents may treat the
registered  holder  of any  warrant  certificate  as the  absolute  owner of the
warrants  evidenced  by that  certificate  for  any  purpose  and as the  person
entitled to exercise the rights attaching to the warrants so requested,  despite
any notice to the contrary.

                              DESCRIPTION OF UNITS

     As specified in the applicable  prospectus  supplement,  we may issue units
consisting  of one or more shares of common  stock,  shares of preferred  stock,
warrants, debt securities or any combination of such securities.  The applicable
prospectus supplement will describe:

  o  the  securities  comprising  the units,  including  whether  and under what
     circumstances the securities comprising the units may be separately traded;

  o  the terms and conditions  applicable to the units,  including a description
     of the terms of any applicable unit agreement governing the units; and

  o  a description of the provisions  for the payment,  settlement,  transfer or
     exchange of the units.

                                GLOBAL SECURITIES

     We may issue the debt  securities,  warrants and units of any series in the
form of one or more fully  registered  global  securities that will be deposited
with a depositary or with a nominee for a depositary  and registered in the name
of the depositary or its nominee.  In that case,  one or more global  securities
will be issued in a denomination or aggregate denominations equal to the portion
of the aggregate principal or face amount of outstanding  registered  securities
of the series to be represented by such global securities.  Unless and until the
depositary  exchanges a global  security in whole for  securities  in definitive
registered form, the global security may not be transferred except as a whole by
the  depositary to a nominee of the depositary or by a nominee of the depositary
to the  depositary or another  nominee of the depositary or by the depositary or
any of its  nominees  to a  successor  of the  depositary  or a nominee  of such
successor.

     The  specific  terms of the  depositary  arrangement  with  respect  to any
portion of a series of securities to be represented by a global security will be
described in the prospectus  supplement  relating to such series.  We anticipate
that the following provisions will apply to all depositary arrangements.

     Ownership of beneficial  interests in a global  security will be limited to
persons that have accounts with the depositary for such global security known as
"participants" or persons that may hold interests through such participants.

     Upon the  issuance of a global  security,  the  depositary  for such global
security will credit,  on its book-entry  registration and transfer system,  the
participants' accounts with the respective principal or face

                                      -36-



amounts of the securities  represented by the global security beneficially owned
by the  participants.  The accounts to be credited  shall be  designated  by any
dealers,  underwriters  or  agents  participating  in the  distribution  of such
securities.

     Ownership of beneficial interests in such global security will be shown on,
and the transfer of such  ownership  interests  will be effected  only  through,
records  maintained by the depositary for such global  security (with respect to
interests of participants)  and on the records of participants  (with respect to
interests of persons holding through participants).  The laws of some states may
require that certain  purchasers  of securities  take physical  delivery of such
securities in definitive  form. Such limits and such laws may impair the ability
to own, transfer or pledge beneficial interests in global securities.

     So long as the depositary  for a global  security,  or its nominee,  is the
registered  owner of such global security,  such depositary or such nominee,  as
the case may be, will be considered  the sole owner or holder of the  securities
represented  by such  global  security  for all  purposes  under the  applicable
indenture, warrant agreement, purchase contract or unit agreement. Except as set
forth below,  owners of  beneficial  interests in a global  security will not be
entitled to have the securities  represented by such global security  registered
in their names,  will not receive or be entitled to receive physical delivery of
such  securities  in definitive  form and will not be  considered  the owners or
holders  thereof under the applicable  indenture,  warrant  agreement,  purchase
contract  or unit  agreement.  Accordingly,  each  person  owning  a  beneficial
interest in a global  security must rely on the procedures of the depositary for
the global security and, if such person is not a participant,  on the procedures
of the participant through which such person owns its interest,  to exercise any
rights of a holder under the applicable indenture,  warrant agreement,  purchase
contract  or  unit  agreement.   We  understand  that  under  existing  industry
practices,  if we request  any action of holders or if an owner of a  beneficial
interest in a global security  desires to give or take any action which a holder
is entitled to give or take under the applicable  indenture,  warrant agreement,
purchase  contract or unit  agreement,  the depositary for such global  security
would authorize the participants  holding the relevant  beneficial  interests to
give or take such  action,  and such  participants  would  authorize  beneficial
owners  owning  through such  participants  to give or take such action or would
otherwise act upon the instructions of beneficial owners holding through them.

     Principal,  premium, if any, and interest payments on debt securities,  and
any payments to holders with  respect to warrants,  purchase  contracts or units
represented by a global  security  registered in the name of a depositary or its
nominee will be made to such  depositary or its nominee,  as the case may be, as
the  registered  owner of such global  security.  None of us, the trustees,  the
warrant  agents,  the  unit  agents  or any of our  other  agents,  agent of the
trustees  or  agent  of  the  warrant  agents  or  unit  agents  will  have  any
responsibility  or  liability  for any  aspect  of the  records  relating  to or
payments  made on account  of  beneficial  ownership  interests  in such  global
security or for  maintaining,  supervising or reviewing any records  relating to
such beneficial ownership interests.

     We expect that the depositary  for any  securities  represented by a global
security,  or its nominee,  upon receipt of any payment of  principal,  premium,
interest or other  distribution  of  underlying  securities  or  commodities  to
holders  in  respect  of  such  global   security,   will   immediately   credit
participants'  accounts in amounts  proportionate to their respective beneficial
interests in such global  security as shown on the records of such depositary or
its  nominee.  We also  expect  that  payments  by  participants  to  owners  of
beneficial interests in such global security held through such participants will
be governed by standing customer instructions and customary practices, as is now
the case with the  securities  held for the accounts of customers in bearer form
or  registered  in  "street  name,"  and  will  be the  responsibility  of  such
participants.

     If the depositary for any securities represented by a global security is at
any time  unwilling  or  unable  to  continue  as  depositary  or ceases to be a
clearing  agency  registered  under the  Exchange  Act,  and we do not appoint a
successor  depositary  registered  as a clearing  agency  under the Exchange Act
within

                                      -37-


90 days, we will issue such  securities in definitive  form in exchange for such
global  security.  In  addition,  we may at any time and in our sole  discretion
determine not to have any of the  securities of a series  represented  by one or
more global  securities and, in such event, will issue securities of such series
in  definitive  form in exchange  for all of the global  security or  securities
representing  such  securities.  Any  securities  issued in  definitive  form in
exchange for a global  security  will be registered in such name or names as the
depositary shall instruct the relevant trustee,  warrant agent or other relevant
agent of ours. We expect that such  instructions  will be based upon  directions
received by the  depositary  from  participants  with  respect to  ownership  of
beneficial interests in such global security.

                              PLAN OF DISTRIBUTION

     We may sell our securities from time to time through underwriters,  dealers
or agents or  directly to  purchasers,  in one or more  transactions  at a fixed
price or prices,  which may be changed,  or at market  prices  prevailing at the
time  of  sale,  at  prices  related  to such  prevailing  market  prices  or at
negotiated prices. We may use these methods in any combination.

BY UNDERWRITERS

     We may use an  underwriter  or  underwriters  in the  offer  or sale of our
securities.

  o  If we use an underwriter or  underwriters,  the offered  securities will be
     acquired by the underwriters for their own account pursuant to the terms of
     an underwriting  agreement between us and the underwriters  entered into at
     the time of sale.

  o  We  will  include  the  names  of  the  specific  managing  underwriter  or
     underwriters,  as well as any  other  underwriters,  and the  terms  of the
     transactions,  including the compensation the underwriters and dealers will
     receive, in the prospectus supplement.

  o  The underwriters will use this prospectus and the prospectus  supplement to
     sell our securities.

     We may also sell securities pursuant to one or more standby agreements with
one or more underwriters in connection with the call,  redemption or exchange of
a specified class or series of any of our outstanding  securities.  In a standby
agreement, the underwriter or underwriters would agree either:

  o  to purchase  from us up to the number of shares of common  stock that would
     be issuable  upon  conversion or exchange of all the shares of the class or
     series of our securities at an agreed price per share of common stock; or

  o  to purchase from us up to a specified  dollar amount of offered  securities
     at an agreed price per offered security, which price may be fixed or may be
     established  by formula or other  method and which may or may not relate to
     market prices of our common stock or any other outstanding security.

     The underwriter or underwriters would also agree, if applicable, to convert
or  exchange  any  securities  of the class or series held or  purchased  by the
underwriter or underwriters into or for our common stock or other security.

     The  underwriter  or  underwriters   may  assist  in  the  solicitation  of
conversions or exchanges by holders of the class or series of securities.

                                      -38-



BY DEALERS

     We may use a dealer to sell our securities.

  o  If we use a dealer,  we, as  principal,  will  sell our  securities  to the
     dealer.

  o  The dealer will then resell our  securities to the public at varying prices
     that the dealer will determine at the time it sells our securities.

  o  We will  include  the name of the dealer and the terms of our  transactions
     with the dealer in the prospectus supplement.

BY AGENTS

     We may designate agents to solicit offers to purchase our securities.

  o  We will name any agent  involved in offering or selling our  securities and
     any commissions that we will pay to the agent in the prospectus supplement.

  o  Unless we indicate otherwise in the prospectus supplement,  our agents will
     act on a best efforts basis for the period of their appointment.

  o  Our agents may be deemed to be underwriters under the Securities Act of any
     of our securities that they offer or sell.

BY DELAYED DELIVERY CONTRACTS

     We may authorize our agents and  underwriters  to solicit offers by certain
institutions  to purchase  our  securities  at the public  offering  price under
delayed delivery contracts.

  o  If we use delayed  delivery  contracts,  we will disclose that we are using
     them in the  prospectus  supplement  and will tell you when we will  demand
     payment  and  delivery  of  the  securities   under  the  delayed  delivery
     contracts.

  o  These delayed  delivery  contracts  will be subject only to the  conditions
     that we set forth in the prospectus supplement.

  o  We  will  indicate  in  the  prospectus   supplement  the  commission  that
     underwriters  and  agents  soliciting  purchases  of our  securities  under
     delayed delivery contracts will be entitled to receive.

     We may  directly  solicit  offers to purchase  our  securities,  and we may
directly sell our securities to institutional or other investors,  including our
affiliates.  We will  describe the terms of our direct  sales in the  prospectus
supplement. We may also sell our securities upon the exercise of rights which we
may issue.

GENERAL INFORMATION

     Underwriters,  dealers and agents that  participate in the  distribution of
our securities  may be  underwriters  as defined in the Securities  Act, and any
discounts or commissions  they receive and any profit they make on the resale of
the offered securities may be treated as underwriting  discounts and commissions
under the  Securities  Act. Any  underwriters  or agents will be identified  and
their  compensation  described  in a  prospectus  supplement.  We may  indemnify
agents,  underwriters and dealers against certain civil  liabilities,  including
liabilities under the Securities Act, or make contributions to payments they may
be required to make relating to those liabilities. Our agents, underwriters, and
dealers,

                                      -39-


or their  affiliates,  may be customers  of,  engage in  transactions  with,  or
perform services for us in the ordinary course of business.

     Each series of securities  offered by this prospectus may be a new issue of
securities  with  no  established  trading  market.  Any  underwriters  to  whom
securities  offered by this  prospectus  are sold by us for public  offering and
sale may make a market in the  securities  offered by this  prospectus,  but the
underwriters  will not be  obligated  to do so and may  discontinue  any  market
making at any time without notice. No assurance can be given as to the liquidity
of the trading market for any securities offered by this prospectus.

     Representatives  of the  underwriters  through whom our securities are sold
for  public  offering  and  sale  may  engage  in  over-allotment,   stabilizing
transactions,   syndicate  short  covering  transactions  and  penalty  bids  in
accordance  with  Regulation M under the Exchange Act.  Over-allotment  involves
syndicate sales in excess of the offering size,  which creates a syndicate short
position.   Stabilizing   transactions  permit  bids  to  purchase  the  offered
securities so long as the stabilizing bids do not exceed a specified maximum.

     Syndicate covering transactions involve purchases of the offered securities
in the open market after the  distribution  has been completed in order to cover
syndicate  short  positions.  Penalty  bids  permit  the  representative  of the
underwriters to reclaim a selling  concession  from a syndicate  member when the
offered  securities  originally sold by such syndicate member are purchased in a
syndicate  covering  transaction  to  cover  syndicate  short  positions.   Such
stabilizing  transactions,  syndicate covering transactions and penalty bids may
cause the price of the offered  securities to be higher than it would  otherwise
be in the absence of such transactions.  These transactions may be effected on a
national securities exchange and, if commenced, may be discontinued at any time.
Underwriters,  dealers and agents may be customers  of,  engage in  transactions
with or perform  services for, us and our subsidiaries in the ordinary course of
business.

                                  LEGAL MATTERS

     The validity of the shares of common stock  offered  hereby has been passed
upon by Morgan, Lewis & Bockius LLP, Philadelphia, Pennsylvania.

                                     EXPERTS

     The   consolidated   financial   statements  of  Cytogen   Corporation  and
subsidiaries as of December 31, 2003 and 2002 and for the years then ended, have
been  incorporated  by  reference  herein and in the  registration  statement in
reliance   upon  the  reports  of  KPMG  LLP,   independent   accountants,   and
PricewaterhouseCoopers  LLP, an  independent  registered public accounting firm,
incorporated  by  reference  herein,  and upon the  authority  of said  firms as
experts in accounting and auditing.  KPMG LLP's audit report refers to its audit
of the adjustments that were applied to restate the 2001 consolidated  financial
statements,  as more fully  described  in Note 1 to the  consolidated  financial
statements.  However,  KPMG LLP was not engaged to and did not audit, review, or
apply any procedures to the 2001  consolidated  financial  statements other than
with respect to such adjustments.

     The  consolidated  balance sheet of Cytogen  Corporation as of December 31,
2001 and the  consolidated  statements of operations,  stockholders'  equity and
cash flows for the year then ended,  have been incorporated by reference in this
prospectus,  and in the  registration  statement of which this  prospectus  is a
part, from the Annual Report on Form 10-K of Cytogen Corporation.  The financial
statements  for the year ended  December  31,  2001 have been  audited by Arthur
Andersen LLP, independent public accountants,  as indicated in their report with
respect thereto,  and are incorporated by reference herein.  The Company has not
received an updated or reissued copy of such report dated  February 5, 2002, and
is  relying  solely  upon the  manually-signed  report  of Arthur  Andersen  LLP

                                      -40-



previously  provided  to the Company in  connection  with the  Company's  Annual
Report on Form 10-K for the year ended  December 31, 2001.  Arthur  Andersen LLP
has not  consented to the inclusion of their report in this  prospectus,  and we
have  dispensed  with the  requirement to file their consent in reliance on Rule
437a  promulgated  under the Securities Act of 1933, as amended.  Because Arthur
Andersen has not consented to the inclusion of their report in this  prospectus,
you will not be able to recover  against Arthur Andersen under Section 11 of the
Securities Act of 1933, as amended, for any untrue statements of a material fact
contained  in  the  financial  statements  audited  by  Arthur  Andersen  or any
omissions to state a material fact required to be stated therein.

                       WHERE YOU CAN FIND MORE INFORMATION

     We file reports, proxy statements and other documents with the SEC. You may
read  and  copy any  document  we file at the  SEC's  public  reference  room at
Judiciary Plaza Building,  450 Fifth Street, N.W., Room 1024,  Washington,  D.C.
20549.  You  should  call  1-800-SEC-0330  for more  information  on the  public
reference  room. Our SEC filings are also available to you on the SEC's Internet
site at http://www.sec.gov.

     This prospectus is part of a registration  statement that we filed with the
SEC. The registration  statement  contains more information than this prospectus
regarding us and our common stock, including certain exhibits and schedules. You
can  obtain a copy of the  registration  statement  from the SEC at the  address
listed above or from the SEC's Internet site.

                      INFORMATION INCORPORATED BY REFERENCE

     The SEC requires us to "incorporate" into this prospectus  information that
we file  with  the SEC in  other  documents.  This  means  that we can  disclose
important  information to you by referring to other  documents that contain that
information.  The information incorporated by reference is considered to be part
of this  prospectus.  Information  contained in this  prospectus and information
that we file with the SEC in the future and  incorporate  by  reference  in this
prospectus automatically updates and supersedes previously filed information. We
incorporate  by reference the documents  listed below and any future  filings we
make with the SEC under  Sections  13(a),  13(c),  14 or 15(d) of the Securities
Exchange  Act of  1934,  prior  to the sale of all the  shares  covered  by this
prospectus.

     (1)       Our Annual  Report on Form 10-K for the year ended  December  31,
               2003,  as filed with the  Securities  and Exchange  Commission on
               March 15, 2004 (File No. 000-14879);

     (2)       Our Current  Report on Form 8-K,  dated April 14, 2004,  as filed
               with the  Securities  and Exchange  Commission  on April 14, 2004
               (File No. 000-14879);

     (3)       Our Current  Report on Form 8-K,  dated April 14, 2004,  as filed
               with the  Securities  and Exchange  Commission  on April 15, 2004
               (File No. 000-14879);

     (4)       Our Quarterly  Report on Form 10-Q for the period ended March 31,
               2004, as filed with the Securities and Exchange Commission on May
               7, 2004 (File No. 000-14879);

     (5)       Our Current  Report on Form 8-K,  dated June 25,  2004,  as filed
               with the  Securities  and  Exchange  Commission  on June 25, 2004
               (File No. 000-14879);

     (6)       Our  Quarterly  Report on Form 10-Q for the period ended June 30,
               2004,  as filed with the  Securities  and Exchange  Commission on
               August 9, 2004 (File No. 000-14879);

     (7)       Our Current Report on Form 8-K, dated September 1, 2004, as filed
               with the Securities and Exchange  Commission on September 2, 2004
               (File No. 000-14879);

                                      -41-



     (8)       Our Current Report on Form 8-K, dated September 3, 2004, as filed
               with the Securities and Exchange  Commission on September 3, 2004
               (File No. 000-14879);

     (9)       Our Current  Report on Form 8-K,  dated  September  10, 2004,  as
               filed with the  Securities  and Exchange  Commission on September
               14, 2004 (File No. 000-14879);

     (10)      Our Current  Report on Form 8-K,  dated  September  27, 2004,  as
               filed with the  Securities  and Exchange  Commission on September
               29, 2004 (File No. 000-14879);

     (11)      Our Current  Report on Form 8-K, dated October 18, 2004, as filed
               with the Securities  and Exchange  Commission on October 19, 2004
               (File No. 000-14879);

     (12)      The description of our common stock contained in our Registration
               Statement  on Form 8-A, as  supplemented  by the  disclosure  set
               forth in Exhibit  3.1 to our Form 10-Q  Quarterly  Report for the
               quarter  ended  June 30,  2000  and  Exhibit  3 to our Form  10-Q
               Quarterly  Report for the  quarter  ended June 30, 1996 (File No.
               000-14879);

     (13)      The  description of our Series C Junior  Participating  Preferred
               Stock  contained  in Exhibit 1 to our Current  Report on Form 8-K
               filed with the  Securities  and Exchange  Commission  on June 24,
               1998 (File No. 333-020015); and

     (14)      All of our filings pursuant to the Exchange Act after the date of
               filing  the   initial   registration   statement   and  prior  to
               effectiveness of the registration statement.

     You may request a copy of these documents, which will be provided to you at
no cost, by writing or telephoning us using the following contact information:

                   Cytogen Corporation
                   650 College Road East, 3rd Floor
                   Princeton, New Jersey 08540
                   Attention:  Senior Vice President and General Counsel
                   Telephone:  609-750-8223

     YOU  SHOULD  RELY ONLY ON THE  INFORMATION  INCORPORATED  BY  REFERENCE  OR
PROVIDED IN THIS PROSPECTUS OR ANY PROSPECTUS SUPPLEMENT. WE HAVE NOT AUTHORIZED
ANYONE  TO  PROVIDE  YOU WITH  INFORMATION  DIFFERENT  FROM  THAT  CONTAINED  OR
INCORPORATED  BY  REFERENCE IN THIS  PROSPECTUS.  THE SELLING  STOCKHOLDERS  ARE
OFFERING TO SELL, AND SEEKING OFFERS TO BUY,  SHARES OF OUR COMMON STOCK ONLY IN
JURISDICTIONS WHERE OFFERS AND SALES ARE PERMITTED. THE INFORMATION CONTAINED IN
THIS PROSPECTUS IS ACCURATE ONLY AS OF THE DATE OF THIS  PROSPECTUS,  REGARDLESS
OF THE TIME OF DELIVERY OF THIS PROSPECTUS OR OF ANY SALE OF COMMON STOCK.

                                      -42-



                                     PART II

                     INFORMATION NOT REQUIRED IN PROSPECTUS

ITEM 14.  OTHER EXPENSES OF ISSUANCE AND DISTRIBUTION.

     The  following  table sets forth the  various  expenses  to be  incurred in
connection with the preparation and filing of this Registration  Statement,  all
of which will be borne by Cytogen  Corporation.  Cytogen  will incur  additional
expenses in connection with any offering of securities registered hereunder. All
amounts  shown are  estimates  except the  Securities  and  Exchange  Commission
registration fee.

     Securities and Exchange Commission ........................   $    8,869

     Legal fees and expenses....................................   $   10,000

     Accounting fees and expenses...............................   $    5,000

     Printing...................................................   $   10,000

     Trustee services...........................................   $   10,000

     Miscellaneous..............................................   $   15,000
                                                                   ----------
          Total Expenses........................................   $   58,869

ITEM 15.  INDEMNIFICATION OF DIRECTORS AND OFFICERS.

     Subsection  (a) of Section  145 of the  Delaware  General  Corporation  Law
empowers a  corporation  to indemnify  any person who was or is threatened to be
made a party to any threatened, pending or completed action, suit or proceeding,
whether civil,  criminal,  administrative or investigative (other than an action
by or in the right of the  corporation)  by reason of the fact that he or she is
or was a director,  officer, employee or agent of the corporation,  or is or was
serving at the request of the  corporation as a director,  officer,  employee or
agent  of  another  corporation,  partnership,  joint  venture,  trust  or other
enterprise,  against expenses (including attorneys' fees), judgments,  fines and
amounts paid in  settlement  actually and  reasonably  incurred by him or her in
connection with such action, suit or proceeding if he or she acted in good faith
and in a manner he or she  reasonably  believed  to be in or not  opposed to the
best interests of the  corporation,  and, with respect to any criminal action or
proceeding, had no reasonable cause to believe his or her conduct was unlawful.

     Subsection  (b) of Section 145  empowers a  corporation  to  indemnify  any
person  who  was or is a  party  or is  threatened  to be  made a  party  to any
threatened,  pending  or  completed  action  or suit by or in the  right  of the
corporation  to procure a judgment in its favor by reason of the fact that he or
she is or was a director,  officer, employee or agent of the corporation,  or is
or was  serving  at the  request  of the  corporation  as a  director,  officer,
employee or agent of another corporation,  partnership,  joint venture, trust or
other  enterprise,  against  expenses  (including  attorneys' fees) actually and
reasonably  incurred by him or her in connection  with the defense or settlement
of such  action or suit if he or she  acted in good  faith and in a manner he or
she  reasonably  believed to be in or not opposed to the best  interests  of the
corporation and except that no  indemnification  shall be made in respect of any
claim,  issue or matter as to which such person  shall have been  adjudged to be
liable  to the  corporation  unless  and only to the  extent  that the  Court of
Chancery or the court in which such action or suit was brought  shall  determine
upon application that,  despite the adjudication of liability but in view of all
of the circumstances of the case, such person is fairly and reasonably  entitled
to indemnity for such  expenses  which the Court of Chancery or such other court
shall deem proper.

                                      II-1



     Section 145 further  provides that to the extent a director or officer of a
corporation has been successful in the defense of any action, suit or proceeding
referred to in subsection  (a) and (b) or in the defense of any claim,  issue or
matter  therein,  he or she shall be  indemnified  against  expenses  (including
attorneys'  fees) actually and  reasonably  incurred by him or her in connection
therewith;  that the indemnification provided by Section 145 shall not be deemed
exclusive  of any other rights to which the  indemnified  party may be entitled;
and that the scope of indemnification extends to directors, officers, employees,
or agents of a constituent corporation absorbed in a consolidation or merger and
persons serving in that capacity at the request of the  constituent  corporation
for another.  Section 145 also empowers a  corporation  to purchase and maintain
insurance  on behalf of a director  or officer of the  corporation  against  any
liability  asserted  against  him or her or  incurred  by him or her in any such
capacity  or  arising  out of his or her  status  as  such  whether  or not  the
corporation  would  have  the  power  to  indemnify  him  or  her  against  such
liabilities under Section 145.

     Section  102(b)(7)  of the  Delaware  General  Corporation  Law  enables  a
corporation in its certificate of incorporation to limit the personal  liability
of members of its board of directors  for  violation  of a director's  fiduciary
duty of care. This section does not, however,  limit the liability of a director
for breaching his or her duty of loyalty, failing to act in good faith, engaging
in intentional misconduct or knowingly violating a law, authorizing a payment of
a dividend or approving a stock  repurchase  in violation of Delaware  Corporate
Law or from any transaction in which the director  derived an improper  personal
benefit.  This  section  also will have no  effect on claims  arising  under the
federal securities laws.

     The Company's  Certificate of  Incorporation  and By-Laws  provide that the
Company shall indemnify  officers and directors and, to the extent  permitted by
the Board of Directors,  employees and agents of the Company, to the full extent
permitted  by and in the  manner  permissible  under  the  laws of the  State of
Delaware.  In addition,  the By-Laws  permit the Board of Directors to authorize
the Company to purchase and maintain  insurance  against any director,  officer,
employee or agent of the Company arising out of his capacity as such.

     Cytogen has obtained  liability  insurance for the benefit of its directors
and officers  which  provides  coverage for losses of directors and officers for
liabilities  arising out of claims  against such persons  acting as directors or
officers  of  Cytogen  (or any  subsidiary  thereof)  due to any breach of duty,
neglect, error, misstatement, misleading statement, omission or act done by such
directors and officers, except as prohibited by law.

ITEM 16.  EXHIBITS AND FINANCIAL SCHEDULES.

       (a)     Exhibits

               1.01   Form of Underwriting Agreement **

               4.01   Form of Senior Indenture **

               4.02   Form of Subordinated Indenture **

               4.03   Certificate of Designations of Preferred Stock **

               4.04   Form of Preferred Stock Certificate **

               4.05   Form of Warrant **

               5.01   Opinion of Morgan, Lewis & Bockius LLP*

               23.01  Consent of KPMG LLP

                                      II-2



               23.02  Consent of PricewaterhouseCoopers LLP

               23.03  Consent  of  Morgan,  Lewis &  Bockius  LLP  (Included  in
                      Exhibit 5.1)

               24.01  Power of Attorney (Included on signature page)

               25.01  Statement of Eligibility of Trustee on Form T-1 **

----------------------

*    To be filed by amendment.

**   To be filed, if necessary, by amendment or as an exhibit to be incorporated
     by reference in the prospectus forming part of this registration statement.

ITEM 17.  UNDERTAKINGS.

     The undersigned Registrant hereby undertakes:

     (1)       To file,  during  any  period in which  offers or sales are being
made, a post-effective amendment to this Registration Statement:

     (i)       To include any  prospectus  required  by Section  10(a)(3) of the
               Securities Act of 1933, as amended (the "Securities Act");

     (ii)      To reflect in the  prospectus  any facts or events  arising after
               the effective  date of this  Registration  Statement (or the most
               recent post-effective  amendment thereof) which,  individually or
               in  the  aggregate,   represent  a  fundamental   change  in  the
               information   set   forth   in   this   Registration   Statement.
               Notwithstanding the foregoing, any increase or decrease in volume
               of  securities  offered (if the total dollar value of  securities
               offered  would not  exceed  that  which was  registered)  and any
               deviation  from  the low or  high  end of the  estimated  maximum
               offering  range may be reflected in the form of prospectus  filed
               with the Commission pursuant to Rule 424(b) if, in the aggregate,
               the changes in volume and price represent no more than 20 percent
               change in the maximum  aggregate  offering price set forth in the
               "Calculation  of   Registration   Fee"  table  in  the  effective
               registration statement; and

     (iii)     To include any material  information  with respect to the plan of
               distribution  not  previously   disclosed  in  this  Registration
               Statement  or any  material  change to such  information  in this
               Registration Statement;

PROVIDED,  HOWEVER,  that  paragraphs  (1)(i)  and  (1)(ii)  do not apply if the
information  required  to be  included in a  post-effective  amendment  by those
paragraphs  is  contained  in periodic  reports  filed with or  furnished to the
Commission  by the  Registrant  pursuant  to Section 13 or Section  15(d) of the
Securities  Exchange Act of 1934,  as amended  (the  "Exchange  Act"),  that are
incorporated by reference in this Registration Statement.

     (2)       That,  for the purposes of  determining  any liability  under the
Securities  Act,  each  post-effective  amendment  shall be  deemed  to be a new
registration  statement  relating to the  securities  offered  therein,  and the
offering of such  securities  at the time shall be deemed to be the initial bona
fide offering thereof.

     (3)       To  remove  from  registration  by  means  of  a   post-effective
amendment  any of the  securities  being  registered  which remain unsold at the
termination of the offering.

                                      II-3



     The Registrant  hereby  undertakes  that,  for purposes of determining  any
liability  under the  Securities  Act,  each filing of the  Registrant's  annual
report  pursuant  to  Section  13(a) or 15(d) of the  Exchange  Act (and,  where
applicable,  each filing of an employee benefit plan's annual report pursuant to
Section  15(d) of the Exchange  Act) that is  incorporated  by reference in this
Registration  Statement  shall  be  deemed  to be a new  registration  statement
relating to the securities offered therein,  and the offering of such securities
at that time shall be deemed to be the initial bona fide offering thereof.

     Insofar as indemnification for liabilities arising under the Securities Act
may  be  permitted  to  directors,  officers  and  controlling  persons  of  the
Registrant  pursuant to the  indemnification  provisions  described  herein,  or
otherwise, the Registrant has been advised that in the opinion of the Securities
and  Exchange  Commission  such  indemnification  is  against  public  policy as
expressed in the Securities Act and is, therefore,  unenforceable.  In the event
that a claim  for  indemnification  against  such  liabilities  (other  than the
payment by the Registrant of expenses incurred or paid by a director, officer or
controlling  person of the Registrant in the  successful  defense of any action,
suit or proceeding) is asserted by such director,  officer or controlling person
in connection with the securities being registered,  the Registrant will, unless
in the  opinion  of its  counsel  the matter  has been  settled  by  controlling
precedent,  submit to a court of appropriate  jurisdiction  the question whether
such  indemnification  by it is  against  public  policy  as  expressed  in  the
Securities Act and will be governed by the final adjudication of such issue.

     The  undersigned   registrant   hereby  undertakes  to  supplement  to  the
prospectus,  after the expiration of the subscription  period,  to set forth the
results of the subscription  offer, the transactions by the underwriters  during
the subscription  period, the amount of unsubscribed  securities to be purchased
by the underwriters,  and the terms of any subsequent reoffering thereof. If any
public offering by the  underwriters is to be made on terms differing from those
set forth in the cover page of the prospectus,  a post-effective  amendment will
be filed to set forth the terms of such offering.

     The undersigned registrant hereby undertakes to file an application for the
purpose of determining  the  eligibility of the trustee to act under  subsection
(a) of Section 310 of the Trust  Indenture Act in accordance  with the rules and
regulations prescribed by the Commission under Section 305(b)(2) of the Act.


                                      II-4



                                   SIGNATURES

     Pursuant to the requirements of the Securities Act of 1933, as amended, the
Registrant certifies that it has reasonable grounds to believe that it meets all
of the requirements for filing on Form S-3 and has duly caused this Registration
Statement  to be  signed  on its  behalf  by  the  undersigned,  thereunto  duly
authorized, in the City of Princeton, State of New Jersey, on November 5, 2004.

                                        CYTOGEN CORPORATION


                                        By: /s/ Michael D. Becker
                                           -------------------------------------
                                           Michael D. Becker
                                           President and Chief Executive Officer







                        SIGNATURES AND POWER OF ATTORNEY

     We, the undersigned officers and directors of Cytogen  Corporation,  hereby
severally constitute and appoint Michael D. Becker and Christopher P. Schnittker
and each of them singly, our true and lawful attorneys with full power to any of
them,  and to each of  them  singly,  to  sign  for us and in our  names  in the
capacities  indicated  below,  the  Registration  Statement  on Form  S-3  filed
herewith and any and all  pre-effective  and  post-effective  amendments to said
Registration  Statement  and  generally  to do all such  things  in our name and
behalf in our capacities as officers and directors to enable Cytogen Corporation
to comply with the provisions of the Securities Act of 1933, as amended, and all
requirements  of the Securities and Exchange  Commission,  hereby  ratifying and
confirming our signatures as they may be signed by our said attorneys, or any of
them, to said Registration Statement and any and all amendments thereto.

     Pursuant to the  requirements  of the  Securities  Act of 1933, as amended,
this  Registration  Statement  has been signed by the  following  persons in the
capacities and on the dates indicated.




                  SIGNATURE                                        TITLE                              DATE
---------------------------------------------  ------------------------------------------  ---------------------------

                                            
/s/ Michael D. Becker
---------------------------------------------  President, Chief Executive Officer and           November 5, 2004
Michael D. Becker                              Director (Principal Executive Officer)

/s/ Christopher P. Schnittker
---------------------------------------------  Senior Vice President and Chief Financial        November 5, 2004
Christopher P. Schnittker                      Officer (Principal Financial and Accounting
                                               Officer)

/s/ John E. Bagalay, Jr.
---------------------------------------------  Director                                         November 5, 2004
John E.  Bagalay, Jr.

/s/ Allen Bloom
---------------------------------------------  Director                                         November 5, 2004
Allen Bloom

/s/ Stephen K. Carter
---------------------------------------------  Director                                         November 5, 2004
Stephen K.  Carter

/s/ James A. Grigsby
---------------------------------------------  Director                                         November 5, 2004
James A. Grigsby

/s/ Robert F. Hendrickson
---------------------------------------------  Director                                         November 5, 2004
Robert F.  Hendrickson

/s/ Kevin G. Lokay
---------------------------------------------  Director                                         November 5, 2004
Kevin G. Lokay





                                  EXHIBIT INDEX

  EXHIBIT
   NUMBER                                 DESCRIPTION
-----------      ---------------------------------------------------------------
    1.01         Form of Underwriting Agreement **

    4.01         Form of Senior Indenture **

    4.02         Form of Subordinated Indenture **

    4.03         Certificate of Designations of Preferred Stock **

    4.04         Form of Preferred Stock Certificate **

    4.05         Form of Warrant **

    5.01         Opinion of Morgan, Lewis & Bockius LLP*

   23.01         Consent of KPMG LLP

   23.02         Consent of PricewaterhouseCoopers LLP

   23.03         Consent  of Morgan, Lewis &  Bockius LLP  (Included in  Exhibit
                 5.1)

   24.01         Power of Attorney (Included on signature page)

   25.01         Statement of Eligibility of Trustee on Form T-1 **



----------------

*  To be filed by amendment.

** To be filed, if necessary, by  amendment or as an  exhibit to be incorporated
   by reference in the prospectus forming part of this registration statement.