EXHIBIT 99.1

                                                                  [CYTOGEN LOGO]

COMPANY CONTACT:
Cytogen Corporation
Stacy Shearer
Investor Relations
(609) 750-8289
sshearer@cytogen.com

      CYTOGEN REPORTS RECORD PRODUCT REVENUES IN THE SECOND QUARTER OF 2004

               Company Reaffirms 2004 Full Year Financial Guidance

PRINCETON,  N.J.,  (AUGUST 5, 2004) -- Cytogen  Corporation  (Nasdaq:  CYTO),  a
product-driven,  oncology-focused  biopharmaceutical company, today reported its
consolidated  financial results for the second quarter and six months ended June
30, 2004 and reaffirmed its 2004 full year financial guidance.

Second quarter sales were strong with total product revenues of $3.9 million for
the quarter  ended June 30, 2004 compared to $1.7 million for the same period in
2003. For the six months ended June 30, 2004, product revenues were $7.5 million
compared to $3.6 million for the same period in 2003.

Cytogen  reported  a net loss of $4.4  million,  or $0.30 per basic and  diluted
share,  for the  quarter  ended  June 30,  2004  compared  to a net loss of $3.4
million,  or $0.37 per basic and diluted share, for the same period in 2003. For
the six months ended June 30, 2004, Cytogen reported a net loss of $8.7 million,
or $0.63 per basic and diluted  share,  compared to $5.3  million,  or $0.60 per
basic and diluted share, for the same period in 2003.

"We are very  pleased to report  another  quarter  of  significant  progress  at
Cytogen,"  said  Michael D.  Becker,  Cytogen's  President  and Chief  Executive
Officer.   "First,  we  are  encouraged  by  the   year-over-year   increase  in
PROSTASCINT(R)  sales that we believe principally resulted from a combination of
increased demand and changes in distributor buying patterns.  Second, the recent
publication and  presentation of new clinical data  re-affirming the benefits of
QUADRAMET(TM),  along with favorable  feedback from continued  market  research,
confirms our  expectations  for  increases in QUADRAMET  sales during the second
half of the year.  We  believe  that key  physicians  share our  excitement  for
QUADRAMET in that they have  expressed  interest in  incorporating  its use into
their  practice,  participating  in our new  product  evaluation  programs,  and
initiating  clinical  studies to enhance both the current and future  utility of
this product.  Finally, we are encouraged by the recent submission of a response
to the  approvable  letter  received from the U.S. Food and Drug  Administration
(FDA) for  COMBIDEX(R)  by  Advanced  Magnetics,  Inc.  and our  efforts are now
focused on appropriate pre-launch preparation and related activities."

PRODUCT REVENUE
- ---------------

QUADRAMET

Sales of  QUADRAMET  (samarium  Sm-153  lexidronam  injection),  a  long-acting,
non-opioid  treatment for the relief of pain due to bone metastases arising from
prostate,  breast, multiple myeloma and other types of cancer, were $1.6 million
for the quarter  ended June 30,  2004.  For the six months  ended June 30, 2004,
QUADRAMET sales were $3.5 million.

Under a 1998 agreement,  Berlex  Laboratories had marketing rights for QUADRAMET
in North and Latin America. Through July 31, 2003, Cytogen received and reported
royalties on product  sales made by Berlex.  Such royalty  revenue from sales of


QUADRAMET during the quarter and six months ended June 30, 2003 was $465,000 and
$914,000, respectively.

On August 1, 2003,  Cytogen  reacquired  these  marketing  rights from Berlex in
exchange  for an upfront cash  payment of $8.0  million and  royalties  based on
future sales of QUADRAMET. At that time, Cytogen began recording product revenue
from the sales of QUADRAMET.

                            QUADRAMET REVENUE SUMMARY
                                 ($ in millions)

                  2003      2003      2003      2003      |     2004      2004
                   Q1        Q2        Q3        Q4       |      Q1        Q2
                  ----      ----      ----      ----      |     ----      ----
Product Sales      n/a       n/a      $1.2      $1.6      |     $1.9      $1.6
Royalties         $0.4      $0.5      $0.2       n/a      |      n/a       n/a
                  ----      ----      ----      ----      |     ----      ----
                                                          |
TOTAL:            $0.4      $0.5      $1.4      $1.6      |     $1.9      $1.6


PROSTASCINT

Sales of  PROSTASCINT  (capromab  pendetide),  the first  commercial  monoclonal
antibody-based  molecular  imaging agent  targeting  prostate-specific  membrane
antigen,  or PSMA,  used to image the extent and spread of prostate  cancer were
$2.3  million for the quarter  ended June 30, 2004  compared to $1.6 million for
the same period in 2003.  For the six months  ended June 30,  2004,  PROSTASCINT
sales were $4.0 million compared to $3.2 million for the same period in 2003.

As previously communicated,  during 2003 Cytogen collected and presented data to
the Centers for Medicare & Medicaid  Services (CMS)  demonstrating  the need for
change  in the  relative  value  of  PROSTASCINT  for  the  hospital  outpatient
prospective  payment  system  (HOPPS).  For  2004,  a  more  appropriate  higher
PROSTASCINT  reimbursement  value was established that the Company believes will
help  ensure  that  hospitals  are  not  discouraged  from  providing   Medicare
beneficiaries  access to this important and clinically  useful molecular imaging
procedure.

                           PROSTASCINT REVENUE SUMMARY
                                 ($ in millions)

                  2003      2003      2003      2003      |     2004      2004
                   Q1        Q2        Q3        Q4       |      Q1        Q2
                  ----      ----      ----      ----      |     ----      ----
Product Sales     $1.6      $1.6      $1.5      $1.8      |     $1.7      $2.3

OTHER PRODUCT REVENUE
- ---------------------

Other product revenue,  consisting of both  brachytherapy  products and NMP22(R)
BLADDERCHEK(R) (nuclear matrix protein-22), a point-of-care, in vitro diagnostic
test for bladder cancer  developed by Matritech,  Inc.,  were not significant in
the first or second  quarters of 2004  compared  to $265,000  and $98,000 in the
first and  second  quarters  of 2003,  respectively.  As  previously  announced,
Cytogen  discontinued  marketing  brachytherapy  products  effective January 24,
2003.  From  November 2002 through  December 31, 2003,  Cytogen  promoted  NMP22
BLADDERCHEK  primarily to urologists in the United  States.  After  December 31,
2003, Cytogen has been selling NMP22 BLADDERCHEK exclusively to oncologists.


COSTS AND EXPENSES
- ------------------

Total  operating  expenses for the quarter ended June 30, 2004 were $8.4 million
compared to $5.7  million for the same period in 2003.  For the six month period
ended June 30, 2004,  operating  expenses were $16.3  million  compared to $10.7
million for the six month period ended June 30, 2003. Operating expenses in 2004
primarily reflect, QUADRAMET and PROSTASCINT manufacturing costs, royalties paid
by Cytogen to Dow Chemical and Berlex  Laboratories  on our sales of  QUADRAMET,
and the amortization of the up-front  payment to Berlex to reacquire  QUADRAMET.
The 2004  operating  expenses  also  include  increased  selling  and  marketing
expenses  related to the  expansion of the  Company's  sales force and marketing
initiatives for the Company's existing oncology products.

The 2004 and 2003 operating expenses also reflect costs associated with the PSMA
Development  Company LLC ("PDC"),  a joint venture between Cytogen and Progenics
Pharmaceuticals,  Inc., for the development of in vivo immunotherapies targeting
prostate specific membrane antigen (PSMA).  Cytogen's share of the equity in the
loss associated with PDC was $542,000 for the second quarter of 2004 compared to
$1.1  million in the second  quarter of 2003.  For the six months ended June 30,
2004, Cytogen's share of the equity in the loss of PDC was $1.4 million compared
to $2.0 million in the same period of 2003.

CASH POSITION
- -------------

Cytogen's cash, cash equivalents and short-term  investments  balance as of June
30, 2004 was $44.8 million compared to $30.2 million as of December 31, 2003. In
April 2004, the Company received net proceeds of approximately  $24.0 million in
connection with a registered  direct offering of 2,570,000  shares of its common
stock.

CLINICAL DEVELOPMENT UPDATE
- ---------------------------

Though  indicated for pain palliation,  preliminary  clinical data suggests that
QUADRAMET  may  have  direct  anticancer  activity.  Accordingly,  QUADRAMET  is
currently being evaluated alone, at higher doses, and in a series of combination
therapy regimens in order to assess potential  synergies with anti-tumor  drugs,
such as docetaxel, and other bone seeking agents, such as zoledronic acid, based
on  demonstrated  clinical  activity  in  hormone-refractory   prostate  cancer,
multiple myeloma and osteosarcoma.  Pending approval by relevant internal review
boards, several new clinical studies are expected to begin in mid-to-late 2004.

YEAR-TO-DATE 2004 HIGHLIGHTS
- ----------------------------

     -    Thomas S. Lytle joined  Cytogen as Senior Vice  President of Sales and
          Marketing to oversee  strategic  sales and marketing  initiatives  for
          Cytogen's existing and future oncology products.
     -    Cytogen  received  net  proceeds  of  approximately  $24.0  million in
          connection with a registered  direct  offering of 2,570,000  shares of
          its common stock.
     -    Clinical data demonstrating that  overexpression of  prostate-specific
          membrane  antigen (PSMA) in primary  prostate  cancer  correlates with
          other  adverse   traditional   prognostic  factors  and  independently
          predicts  disease  recurrence  was  reported  in the  medical  journal
          Clinical    Cancer   Research    ("Correlation    of   Primary   Tumor
          Prostate-Specific  Membrane Antigen Expression with Disease Recurrence
          in Prostate Cancer,"  Clinical Cancer Research,  Volume 9, No. 17, pp.
          6357-6362).
     -    Positive   results  from  the   collaboration   between   Cytogen  and
          researchers  at  the  Kimmel  Cancer  Institute  at  Thomas  Jefferson
          University  designed to identify novel  interactions  associated  with


          Wwox, a tumor suppressor protein, were published in the Proceedings of
          the  National  Academy of  Sciences  (PNAS)  ("Functional  association
          between Wwox tumor  suppressor  protein and p73, a p53 homolog," PNAS,
          Volume 101, No. 13, pp. 4401-4406).
     -    A   prospective,    randomized,    double-blind   multi-center   study
          demonstrating  that  QUADRAMET both provides  significant  pain relief
          from bone metastases secondary to prostate cancer and enables patients
          to significantly  decrease their use of opioid analgesics was reported
          in the May 2004 issue of the  peer-reviewed  medical  journal  Urology
          ("Samarium-153-  Lexidronam  Complex  for  Treatment  of Painful  Bone
          Metastases in Hormone-  Refractory  Prostate Cancer," Urology,  Volume
          63, No. 5, pp. 940-945).
     -    The findings of three  separate  studies  relating to  QUADRAMET  were
          presented  at the 40th  Annual  Meeting  of the  American  Society  of
          Clinical  Oncology  (ASCO).  The  studies   demonstrated  the  use  of
          QUADRAMET in  conjunction  with other  therapies  for the treatment of
          bone  metastases  secondary to prostate  cancer,  breast  cancer,  and
          multiple myeloma.
     -    Cytogen was added to the Russell  3000(R) Index when the  broad-market
          index was reconstituted on June 25, 2004.
     -    Advances in prostate cancer imaging using  PROSTASCINT  were presented
          at the 51st Annual Meeting of the Society of Nuclear Medicine.
     -    Advanced  Magnetics,  Inc.  and  Cytogen  Corporation  announced  that
          Advanced  Magnetics  submitted  a response  to the  approvable  letter
          received  from  the  U.S.  Food  and  Drug  Administration  (FDA)  for
          COMBIDEX,  an  investigational  molecular  imaging agent to aid in the
          non-invasive diagnosis of metastatic lymph nodes.

FINANCIAL OUTLOOK FOR 2004
- --------------------------

The Company reaffirms its previous issued financial guidance as follows:

- -- Reflecting  only QUADRAMET and  PROSTASCINT,  Cytogen  expects an increase in
2004 full year product revenue of approximately 65% to 75% over its 2003 product
revenue of $9.8 million;

- -- In 2004,  Cytogen expects an average gross margin of approximately 40%, which
reflects  QUADRAMET  and  PROSTASCINT  manufacturing  costs and royalties to Dow
Chemical and Berlex Laboratories;

- -- In 2004, Cytogen expects an increase in its full year total selling,  general
and  administrative  expenses of  approximately 55% to 60% compared to the $11.6
million  incurred in these areas in 2003 due primarily to sales force  expansion
and other marketing  initiatives  associated with the  commercialization  of the
Company's existing and anticipated oncology products;

- -- Cytogen  expects  an  increase  in 2004 full year  research  and  development
expenses of  approximately  55% to 60% over its 2003  research  and  development
expenses of $2.7 million due primarily to  investigational  studies  relating to
QUADRAMET; and

- -- In  2004,  Cytogen  expects  an  increase  in its  share of the  equity  loss
associated with the PDC joint venture of  approximately  30% over its 2003 share
of the equity loss of $3.5 million due  primarily  to third party  manufacturing
and  development  costs  related  to  PDC's  monoclonal   antibody  programs  in
preparation for initiation of human clinical trials.


The statements  made in the foregoing  paragraphs  under the heading  "Financial
Outlook  for 2004" are  forward-looking  statements,  subject to the  disclosure
notice paragraph regarding forward-looking statements set forth below.

CONFERENCE CALL & WEBCAST INFORMATION
- -------------------------------------

Cytogen will  broadcast its  quarterly  investor  conference  call live over the
Internet today, Thursday,  August 5, 2004 at 9:00 a.m. Eastern Time. The dial-in
number for the U.S. is  800-901-5213  and the dial-in  number for  international
callers is 617-786-2962.  The pass code number is 17064226.  This event can also
be accessed by going to  Cytogen's  Web site,  www.cytogen.com,  and clicking on
Investor  Relations.  A link to the  webcast  is under  the  Calendar  of Events
header.   The  event  will  be  archived  and  available  for  replay   starting
approximately  one hour after the call and continuing for 7 days  thereafter.  A
replay of the  conference  call will be available  for seven days  following the
call.  The replay dial-in  number for the U.S. is  888-286-8010  and the dial-in
number for international callers is 617-801-6888. The replay pass code number is
39220111.

NOTE:
- -----

QUADRAMET  is  indicated  for the  relief  of pain in  patients  with  confirmed
osteoblastic  metastatic  bone lesions that enhance on  radionuclide  bone scan.
This  press  release  describes  clinical  applications  that  differ  from that
reported in the QUADRAMET package insert.

PROSTASCINT  is  indicated  as a  diagnostic  imaging  agent in newly  diagnosed
patients with biopsy-proven  prostate cancer, thought to be clinically localized
after standard diagnostic  evaluation and who are thought to be at high risk for
pelvic  lymph node  metastases.  PROSTASCINT  is also  indicated as a diagnostic
imaging agent in post-prostatectomy patients with a rising PSA and a negative or
equivocal  standard  metastatic  evaluation  in whom  there  is a high  clinical
suspicion of occult metastatic  disease.  This press release describes  clinical
applications  and imaging  performance  that differs  from that  reported in the
PROSTASCINT package insert.

A copy of the full prescribing information for QUADRAMET, PROSTASCINT, and NMP22
BLADDERCHEK may be obtained in the U.S. from Cytogen Corporation by calling toll
free 800-833-3533 or by visiting the web site at  www.cytogen.com,  which is not
part of this press release.

ABOUT CYTOGEN CORPORATION
- -------------------------

Founded in 1980,  Cytogen  Corporation  of  Princeton,  NJ is a  product-driven,
oncology-focused  biopharmaceutical  company that develops and  commercializes a
balanced  portfolio of oncology products that address the unmet medical needs of
patients  and  the  physicians  that  serve  them.   Cytogen   directly  markets
QUADRAMET(TM) (samarium Sm-153 lexidronam injection),  PROSTASCINT(R)  (capromab
pendetide) kit for the  preparation  of Indium In-111  capromab  pendetide,  and
NMP22(R)  BLADDERCHEK(R)  (nuclear  matrix  protein-22)  in the  United  States.
Cytogen  has  exclusive   United   States   marketing   rights  to   COMBIDEX(R)
(ferumoxtran-10),  an investigational molecular imaging agent consisting of iron
oxide  nanoparticles  for use in conjunction with magnetic  resonance imaging to
aid in the  differentiation of cancerous and non-cancerous lymph nodes, which is
under  review  by the  U.S.  Food  and  Drug  Administration.  Cytogen  is  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.  Full prescribing  information for the Company's


products is available at www.cytogen.com or by calling 1-800-833-3533.  For more
information, please visit the Company's website at www.cytogen.com, which is not
part of this press release.


This press release contains  certain  "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.  All statements,  other than
statements of  historical  facts,  included in this press release  regarding our
strategy,  future operations,  financial  position,  future revenues,  projected
costs,  prospects,  plans  and  objectives  of  management  are  forward-looking
statements.  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.  There are a number of important  factors that could
cause  Cytogen's  results  to differ  materially  from those  indicated  by such
forward-looking  statements.  In particular,  Cytogen's business is subject to a
number of significant risks, which include,  but are not limited to: the risk of
obtaining  the  necessary  regulatory  approvals;  the risk of whether  products
result  from  development  activities;  the  risk of  shifts  in the  regulatory
environment  affecting  sales of Cytogen's  products such as  third-party  payor
reimbursement  issues;  the risk  associated  with  Cytogen's  dependence on its
partners for development of certain projects, as well as other factors expressed
from time to time in Cytogen's periodic filings with the Securities and Exchange
Commission  (the  "SEC").  As a result,  this  press  release  should be read in
conjunction with Cytogen's  periodic  filings with the SEC. The  forward-looking
statements  contained herein are made only as of the date of this press release,
and Cytogen  undertakes no obligation  to publicly  update such  forward-looking
statements to reflect subsequent events or circumstances.

                                       ###






                              CYTOGEN CORPORATION & SUBSIDIARIES
                       (All amounts in thousands except per share data)
                                          (Unaudited)



                             CONDENSED CONSOLIDATED STATEMENT OF OPERATIONS




                                              THREE MONTHS ENDED         SIX MONTHS ENDED
                                                    JUNE 30,                  JUNE 30,
                                             --------------------      --------------------
                                                2004        2003         2004         2003
                                             --------    --------      --------    --------
                                                                       
Revenues:
    Quadramet                                $  1,616    $      -      $  3,470    $      -
    ProstaScint                                 2,312       1,599         4,039       3,219
    Others                                          -          98             1         363
                                             --------    --------      --------    --------
           Total Product Revenue                3,928       1,697         7,510       3,582

Royalty Revenue                                     -         465             -         914
License and Contract Revenue                       24         164            43         307
                                             --------    --------      --------    --------
           Total Revenues                       3,952       2,326         7,553       4,803
                                             --------    --------      --------    --------

Operating Expenses:
    Cost of Product Related Revenue             2,396         900         4,795       1,810
    Selling, General and Administrative         4,914       2,967         8,805       5,366
    Research and Development                      541         718         1,345       1,530
    Equity in Loss of Joint Venture               542       1,086         1,351       1,966
                                             --------    --------      --------    --------
           Total Operating Expenses             8,393       5,671        16,296      10,672
                                             --------    --------      --------    --------

Interest Income (Expense), Net                     57         (23)           77         (34)
Income Tax Benefit                                  -           -             -        (584)
                                             --------    --------      --------    --------
Net Loss                                     $ (4,384)   $ (3,368)     $ (8,666)   $ (5,319)
                                             ========    ========      ========    ========

Basic and Diluted Net Loss Per Share         $  (0.30)   $  (0.37)     $  (0.63)   $  (0.60)
                                             ========    ========      ========    ========

Weighted Average Common Shares Outstanding     14,848       9,051        13,859       8,909
                                             ========    ========      ========    ========





                      CONDENSED CONSOLIDATED BALANCE SHEETS




                                                          JUNE 30,     DECECEMBER 31,
                                                            2004            2003
                                                        -----------    --------------

                                                                   
Assets:
    Cash, Cash Equivalents and Short-Term Investments    $  44,840       $  30,215
    Accounts Receivable, Net                                 1,946           1,445
    Inventories                                              1,432           1,887
    Property and Equipment, Net                                747             595
    Quadramet License Fee, Net                               7,372           7,720
    Other Assets                                             1,586           1,833
                                                         ---------       ---------
           Total Assets                                  $  57,923       $  43,695
                                                         =========       =========

Liabilities and Stockholders' Equity:
    Accounts Payable and Accrued Liabilities             $   4,002       $   5,125
    Other Current Liabilities                                   58              76
    Long-Term Liabilities                                    2,457           2,454
    Stockholders' Equity                                    51,406          36,040
                                                         ---------       ---------
           Total Liabilities and Stockholders' Equity    $  57,923       $  43,695
                                                         =========       =========