UNITED STATES

                       SECURITIES AND EXCHANGE COMMISSION

                             WASHINGTON, D.C. 20549

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

                                    FORM 8-K/A

                                 CURRENT REPORT

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

        Date of report (Date of earliest event reported): April 20, 2006
                                                          --------------

                               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))





ITEM 2.01    COMPLETION OF ACQUISITION OR DISPOSITION OF ASSETS

     This Form  8-K/A  amends  the Form 8-K filed by  Cytogen  Corporation  (the
"Company")  on  April  26,  2006  with  respect  to the sale by the  Company  to
Progenics  Pharmaceuticals,  Inc.  ("Progenics")  of the Company's 50% ownership
interest in PSMA  Development  Company LLC (the "Joint  Venture").  On April 20,
2006, the Company  entered into a Membership  Interest  Purchase  Agreement with
Progenics  providing  for the sale to Progenics of the  Company's  50% ownership
interest in the Joint Venture. In addition,  the Company entered into an Amended
and Restated  PSMA/PSMP  License  Agreement with Progenics and the Joint Venture
pursuant to which the Company  licensed the Joint Venture certain rights in PSMA
technology.  Under  the  terms  of such  agreements,  the  Company  sold its 50%
interest in the Joint  Venture  for an upfront  cash  payment of $13.2  million,
potential  future  milestone  payments  totaling up to $52 million  payable upon
regulatory approval and commercialization of the Joint Venture products,  and an
undisclosed royalty on future product sales of the Joint Venture.

     The following  unaudited pro forma balance sheet information of the Company
reflects the  disposition of the Joint Venture as if it had occurred on December
31,  2005.  The  accompanying  unaudited  pro  forma  statements  of  operations
information for the years ended  December 31,  2005, 2004 and 2003,  reflect the
disposition of the Joint Venture as if the sale had occurred on January 1, 2003.
The pro forma  adjustments  are  based on the  operations  of the Joint  Venture
during the periods  presented and the impact from the sale of the Joint Venture.
Consequently,  the pro forma financial  information presented is not necessarily
indicative  of the results that would have been  reported  had the  transactions
actually  occurred  on the dates  specified.  The pro forma  adjustments  do not
include any gains the Company may record in connection with this transaction.

     The pro forma  adjustments  for the years ended December 31, 2005, 2004 and
2003, from the sale of the Company's 50% ownership interest in the Joint Venture
would have  reduced  license and  contract  revenue by  $185,000,  $106,000  and
$214,000,  respectively,  equity in loss of Joint Venture by $3.2 million,  $2.9
million, and $3.5 million,  respectively, and Loss from Continuing Operations by
$3.0 million, $2.8 million and $3.2 million,  respectively,  or $0.17, $0.19 and
$0.32 per basic and diluted share. In addition,  the pro forma adjustments as of
December 31, 2005 from the sale of the Company's  50% ownership  interest in the
Joint Venture would have  increased  cash and cash  equivalents by $3.8 million,
and reduced other Assets by $775,000 and Accumulated Deficit by $3.0 million.

     The  unaudited  pro  forma  condensed   balance  sheet  and  Statements  of
Operations information reflect the historical financial information adjusted for
the pro forma adjustments discussed above:




                      CYTOGEN CORPORATION AND SUBSIDIARIES
                 PRO FORMA CONDENSED CONSOLIDATED BALANCE SHEETS
                             AS OF DECEMBER 31, 2005
           (All amounts in thousands, except share and per share data)
                                   (Unaudited)




                                                                                    December 31,
                                                                                        2005
                                                                                     -----------
                                                                                 
ASSETS:
Current assets:
      Cash and cash equivalents.................................................    $    34,102
      Accounts receivable, net..................................................          1,743
      Inventories...............................................................          3,582
      Property and equipment, net...............................................            886
      Quadramet license fee, net................................................          6,327
      Other assets..............................................................          1,140
                                                                                    -----------
                                                                                    $    47,780
                                                                                    -----------

LIABILITIES AND STOCKHOLDERS' EQUITY:

      Accounts payable and accrued liabilities..................................          5,271
      Warrant liability.........................................................          1,869
      Other liabilities.........................................................             72
                                                                                    -----------
                                                                                    -----------
            Total liabilities...................................................          7,212
                                                                                    -----------

Commitments and contingencies

Stockholders' equity:
      Preferred stock, $.01 par value, 5,400,000 shares authorized - Series C
         Junior Participating Preferred Stock, $.01 par value, 200,000 shares
         authorized, none issued and outstanding................................            --
      Common stock, $.01 par value, 50,000,000 shares authorized, 22,473,762
         and 15,489,116 shares issued and outstanding at December 31, 2005 and
         December 31, 2004, respectively........................................            225
      Additional paid-in capital................................................        450,502
      Unearned compensation.....................................................          (610)
      Accumulated other comprehensive income....................................             28
      Accumulated deficit.......................................................       (409,577)
                                                                                    -----------
            Total stockholders' equity..........................................         40,568
                                                                                    -----------
                                                                                    -----------
                                                                                    $    47,780
                                                                                    -----------








                      CYTOGEN CORPORATION AND SUBSIDIARIES
            PRO FORMA CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS
          (All amounts in thousands, except share and per share data)
                                   (Unaudited)






                                                                                        Year Ended December 31,
                                                                                2005            2004               2003
                                                                           -------------- --------------   ---------------
                                                                                                   
REVENUES:
      Product related:
            PROSTASCINT...................................................  $      7,407    $    7,186      $    6,523
            QUADRAMET.....................................................         8,350         7,293           2,765
            NMP22 BLADDERCHEK.............................................           --              1             295
            BRACHYSEED....................................................           --             --             240
                                                                            ===========     ==========      ===========
                  Total product revenues..................................        15,757        14,480           9,823
      QUADRAMET royalties.................................................           --             --           1,105
                                                                            ===========     ==========      ==========

                  Total product related revenues..........................        15,757        14,480          10,928
      License and contract................................................             4            33           2,700
                                                                            ============    ==========      ==========

                  Total revenues..........................................        15,761        14,513          13,628
                                                                            ============    ==========      ==========
OPERATING EXPENSES:
      Cost of product related revenues....................................         9,621         9,309           6,268
      Selling, general and administrative.................................        25,895        20,318          11,867
      Research and development............................................         6,064         3,206           2,342
      Equity in loss of joint venture.....................................           --             --            --
      Impairment of intangible assets.....................................           --             --            115
                                                                            ============    ==========      ==========


                  Total operating expenses................................        41,580        32,833          20,592
                                                                            ============    ==========      ==========


                  Loss from continuing operations.........................       (25,819)      (18,320)         (6,964)
Interest income...........................................................           712           448             141
Interest expense..........................................................          (114)         (185)           (185)
Decrease in value of warrant liability....................................         1,666           --               --
                                                                            ============     ==========      ==========


                  Loss before income taxes................................       (23,555)      (18,057)        (10,246)
Income tax benefit........................................................          (256)         (307)           (888)
                                                                            =============    ==========      ==========


Net loss..................................................................  $    (23,299    $  (17,750)     $   (6,120)
                                                                            ============    ===========     ===========


Basic and diluted net loss per share......................................  $      (1.36)   $    (1.21)     $    (0.60)
                                                                            ============    ===========     ===========


Weighted-average common shares outstanding................................        17,117        14,654          10,205
                                                                            ============    ==========      ==========






                                   SIGNATURES


     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 Officer

Dated:   April 26, 2006