EXHIBIT 99.1


                                                                  [CYTOGEN LOGO]



COMPANY CONTACT:
Cytogen Corporation
Stacy Shearer
Investor Relations
(609) 750-8289
sshearer@cytogen.com
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    CYTOGEN REACQUIRES MARKETING RIGHTS TO QUADRAMET(R) PAIN THERAPY PRODUCT

PRINCETON, N.J., (AUGUST 1, 2003) -- Cytogen Corporation (Nasdaq: CYTO) today
announced that the Company completed the reacquisition of marketing rights held
by Berlex Laboratories, a U.S. affiliate of Schering AG, Germany (NYSE: SHR), to
QUADRAMET(R) (Samarium Sm 153 Lexidronam) in North and Latin America in exchange
for an upfront payment of $8 million and royalties based on future sales.
QUADRAMET is a skeletal targeting therapeutic radiopharmaceutical for the relief
of pain due to bone metastases arising from prostate, breast, multiple myeloma
and other types of cancer.

"Cytogen is very pleased to be able to offer QUADRAMET to customers through its
in-house specialty sales force that already calls upon urologists and radiation
oncologists," said Michael D. Becker, President and Chief Executive Officer of
Cytogen Corporation. "Our reacquisition of marketing rights to QUADRAMET in the
U.S. provides an excellent opportunity to accelerate Cytogen's product-driven,
oncology-focused business model, and we believe that the addition of QUADRAMET
to our marketed product portfolio has great significance for Cytogen's future
growth. In addition to providing pain relief, recently reported and ongoing
clinical studies suggest that certain unique properties of QUADRAMET may allow
it to be used in combination with other drugs, such as chemotherapeutics and
bisphosphonates, to treat a variety of cancers. We intend to continue to
aggressively pursue these investigational applications."

Under a 1998 agreement, Berlex had marketing rights to QUADRAMET in North and
Latin America. Under this agreement, Cytogen received and reported royalties on
product sales made by Berlex. In 2002, Berlex recorded QUADRAMET sales of
approximately $7.36 million, for which Cytogen recorded $1.84 million in royalty
revenue. Effective immediately, Cytogen will begin receiving and recording all
revenue from the sales of QUADRAMET, less a continuing obligation to make
royalty payments to Berlex. Schering AG, which acquired CIS Bio International in
2000, will continue to market Quadramet in Europe as a direct licensee of Dow.

In 1993, Cytogen obtained a license to manufacture, use and sell QUADRAMET under
an agreement with the Dow Chemical Company. QUADRAMET is a skeletal targeting
therapeutic radiopharmaceutical consisting of a short half-life therapeutic
radionuclide (Samarium-153) bound to a small-molecule, bone-seeking phosphonate
(EDTMP) that targets and accumulates in osteoblastic sites (areas of new bone
formation), thereby delivering radioactivity in areas that have been invaded by
metastatic tumor. In 1997, Cytogen received clearance from the United States
Food and Drug Administration (FDA) to market QUADRAMET to treat pain associated
with confirmed osteoblastic metastatic bone lesions that enhance on radionuclide


bone scan. Osteoblastic bone lesions can be associated with advanced prostate,
breast, multiple myeloma and other cancers that have metastasized to bone, which
can cause pain that may be severe and difficult to treat.

According to the American Cancer Society, approximately 1.33 million new cancer
cases are expected to occur in the United States during 2003. Research indicates
that many patients with advanced cancer develop bone metastasis, the spread of
cancerous cells from the original tumor to bones. Often, bone is the only site
of metastasis in these patients. Pain is one of the most common symptoms
associated with cancer, occurring in approximately one quarter of patients with
newly diagnosed malignancies, one third of patients undergoing treatment, and
three quarters of patients with advanced disease. Studies have shown that many
patients with cancer (especially older adults) do not receive adequate pain
relief. Effective pain control can help patients stay involved not only in their
cancer treatment but also in the activities of daily living. When pain is under
control, people may have better appetites, and may be better able to get restful
sleep. Pain relief also means stress relief because constant discomfort is a
direct cause of anxiety, anger, fear, and depression.

The World Health Organization (WHO) has devised a simple, three-step analgesic
ladder for managing cancer pain. The first tier offers nonsteroidal
anti-inflammatory drugs (NSAIDs). With increasing symptoms, the second tier adds
a weak opioid to the NSAID. If pain persists or worsens, the third tier
substitutes a strong opioid. However, opioids are associated with sedation,
fatigue, nausea, vomiting, confusion, constipation, urinary retention, sexual
dysfunction, itching, sleep disturbances, and dry mouth. In controlled clinical
trials, patients receiving QUADRAMET experienced significant improvements in
pain scores that correlated with their ability to decrease the use of opioid
analgesics.

Some patients may experience a slight increase in bone pain (called a flare)
within a few days of receiving QUADRAMET. However, this is usually temporary and
can be relieved by over-the-counter analgesic products. Because QUADRAMET causes
myelosuppression, prior to administration, clinical benefits should be judged to
outweigh the risks in patients having compromised bone marrow reserves or
undergoing other therapies that cause myelosuppression.

Patients who respond to QUADRAMET might begin to notice the onset of pain relief
one week after injection and may be encouraged to decrease their use of opioid
analgesics. Any QUADRAMET not taken up by the bone is rapidly excreted from the
body, normally within 6 hours. This rapid excretion minimizes radiation exposure
to normal bone marrow and limits the myelosuppressive (suppression of bone
marrow) effects of QUADRAMET. The myelosuppressive effect is temporary and
typically recovers to pretreatment levels within 8 weeks.

QUADRAMET is manufactured by Bristol-Myers Squibb Medical Imaging, Inc.
(formerly DuPont Pharmaceuticals). Full prescribing information for QUADRAMET
may be obtained in the U.S. from Cytogen Corporation by calling toll free
800-833-3533 or by visiting the web site at http://www.quadramet.com.

About Cytogen Corporation

Cytogen Corporation of Princeton, NJ is a product-driven, oncology-focused
biopharmaceutical company. Cytogen markets proprietary and licensed oncology
products through its in-house specialty sales force: ProstaScint(R) (a

monoclonal antibody-based imaging agent used to image the extent and spread of
prostate cancer); Quadramet(R) (a skeletal targeting therapeutic
radiopharmaceutical for the relief of pain due to bone metastases arising from
prostate and other types of cancer); and NMP22(R) BladderChek(TM) (a
point-of-care, in vitro diagnostic test for bladder cancer). Cytogen has
exclusive U.S. marketing rights to Combidex(R), an ultrasmall superparamagnetic
iron oxide contrast agent for magnetic resonance imaging of lymph nodes that is
pending clearance by the U.S. Food and Drug Administration. Cytogen's pipeline
comprises product candidates at various stages of clinical development,
including fully human monoclonal antibodies and cancer vaccines based on PSMA
(prostate specific membrane antigen) technology, which was exclusively licensed
from Memorial Sloan-Kettering Cancer Center. Cytogen also conducts research in
cellular signaling through its AxCell Biosciences research division in Newtown,
PA. 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. The words "anticipates," "believes," "estimates," "expects,"
"intends," "may," "plans," "projects," "will," "would" and similar expressions
are intended to identify forward-looking statements, although not all
forward-looking statements contain these identifying words. 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, and the risk
associated with Cytogen's dependence on its partners for development of certain
projects. Cytogen cannot guarantee that Cytogen will actually achieve the plans,
intentions or expectations disclosed in any such forward-looking statements.
Cytogen's actual results may differ materially from Cytogen's historical results
of operations and those discussed in such forward-looking statements and the
risks stated above for various reasons, including, but not limited to, Cytogen's
ability to carry out its business and financial plans, to successfully
commercialize QUADRAMET(R), to determine and implement the appropriate strategic
initiative for its AxCell Biosciences subsidiary, to fund development necessary
for existing products and to pursue new product opportunities, to integrate
in-licensed products such as NMP22(R) BladderChek(TM), to establish and
successfully complete clinical trials where required for product approval, to
obtain foreign regulatory approvals for products and to establish marketing
arrangements in countries where approval is obtained, and other factors
discussed in Cytogen's Form 10-K for the year ended December 31, 2002, as
amended, and from time-to-time in Cytogen's other filings with the Securities
and Exchange Commission. Any forward-looking statements made by Cytogen do not
reflect the potential impact of any future acquisitions, mergers, dispositions,
joint ventures or investments Cytogen may make. Cytogen does not assume, and
specifically disclaims, any obligation to update any forward-looking statements,
and these statements represent Cytogen's current outlook only as of the date
given.

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