WASHINGTON, D.C. 20549


                                    FORM 8-K

                                 CURRENT REPORT

                     PURSUANT TO SECTION 13 OR 15(D) OF THE
                         SECURITIES EXCHANGE ACT OF 1934

       Date of report (Date of earliest event reported): February 1, 2005

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

          Delaware                    000-14879                 22-2322400
----------------------------   ------------------------   ----------------------
(State or Other Jurisdiction   (Commission File Number)     (I.R.S. Employer
     of Incorporation)                                     Identification No.)

  650 College Road East, CN 5308, Suite 3100, Princeton, NJ           08540
-------------------------------------------------------------    ---------------
         (Address of Principal Executive Offices)                  (Zip Code)

       Registrant's telephone number, including area code:  (609) 750-8200

         (Former Name or Former Address, if Changed Since Last Report)

     Check the  appropriate  box below if the Form 8-K  filing  is  intended  to
simultaneously  satisfy the filing obligation of the registrant under any of the
following provisions (see General Instruction A.2. below):

     |_|  Written communications  pursuant to Rule 425 under the  Securities Act
(17 CFR 230.425)

     |_|  Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17
CFR 240.14a-12)

     |_|  Pre-commencement  communications  pursuant to Rule 14d-2(b)  under the
Exchange Act (17 CFR 240.14d-2(b))

     |_|  Pre-commencement  communications  pursuant to Rule 13e-4(c)  under the
Exchange Act (17 CFR 240.13e-4(c))


     On February  1, 2005,  Advanced  Magnetics,  Inc.  and Cytogen  Corporation
announced that the U.S. Food and Drug Administration's  Oncologic Drugs Advisory
Committee  (ODAC) is scheduled to review the regulatory  filing for Combidex(R),
Advanced Magnetics'  investigational  molecular imaging agent, on March 3, 2005.
The companies are jointly preparing for the upcoming ODAC meeting.

     Combidex  (ferumoxtran-10)  consists of iron oxide nanoparticles for use in
conjunction with magnetic resonance imaging (MRI) to aid in the  differentiation
of cancerous from non-cancerous lymph nodes.

     Combidex received an approvable letter, subject to certain conditions, from
the FDA in June 2000. In September 2004, Advanced Magnetics submitted a complete
response to the approvable letter,  which was accepted by the FDA and assigned a
user fee goal date of March 30, 2005.

     The full text of the February 1, 2005 press  release  issued in  connection
with the announcement is attached as Exhibit 99.1 to this Current Report on Form
8-K, and is  incorporated  herein by  reference.  The foregoing  description  is
qualified in its entirety by reference to such Exhibit.


(c)  Exhibits.

     Exhibit  No.      Description
     ------------      -----------

        99.1           Press  Release of  Advanced Magnetics  and Cytogen  dated
                       February 1, 2005


     Pursuant to the  requirements  of the Securities  Exchange Act of 1934, the
Registrant  has duly  caused  this  report  to be  signed  on its  behalf by the
undersigned hereunto duly authorized.

                                                CYTOGEN CORPORATION

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

Dated:   February 1, 2005

                                  EXHIBIT INDEX

      Exhibit No.       Description
      -----------       -----------

         99.1           Press Release  of Advanced  Magnetics and  Cytogen dated
                        February 1, 2005