File No. 333-120262
                                                      Filed under Rule 424(b)(3)
 
               PROSPECTUS SUPPLEMENT NO. 2 DATED DECEMBER 14, 2005
 
     To the Prospectus dated November 5, 2004 as supplemented by Prospectus
                      Supplement No. 1 dated July 20, 2005
 
                               CYTOGEN CORPORATION


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This prospectus supplement supplements,  and should be read in conjunction with,
the prospectus, dated November 5, 2004, as supplemented by Prospectus Supplement
No. 1 dated July 20, 2005,  relating to $70,000,000 of debt  securities,  common
stock,  preferred stock, warrants and units that we may offer and sell from time
to time.  We will  receive all of the proceeds  from any  securities  sold.  The
prospectus  was  filed as part of our  registration  statement  on Form S-3 (No.
333-120262).
 
We are  offering  up to  3,729,556  shares of our common  stock and  warrants to
purchase  932,389  shares  of our  common  stock  to one or  more  institutional
investors   pursuant  to  this  prospectus   supplement  and  the   accompanying
prospectus.  The common stock and warrants  will be purchased at the  negotiated
unit price of $3.56 per unit. We are also offering  warrants to purchase 186,478
shares  of our  common  stock  that are  being  issued  as  compensation  to the
placement agent in the transaction.
 
Our  common  stock is quoted on the  Nasdaq  National  Market  under the  symbol
"CYTO." On December 12, 2005,  the last  reported sale price of our common stock
on the Nasdaq National Market was $3.54 per share.

Rodman & Renshaw,  LLC has been  retained  to act as  placement  agent for us in
connection  with the  arrangement  of this  transaction.  We have  agreed to pay
Rodman & Renshaw,  LLC the aggregate placement agent fees set forth in the table
below. The placement agent is not required to sell any specific number or dollar
amount of shares, but will use reasonable efforts to arrange for the sale of all
3,729,556  of  the  shares  and  all  932,389  of the  warrants.  See  "Plan  of
Distribution" in this prospectus supplement.


                                                          Per          Maximum
                                                          Unit        Offering

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

Price to the public                                      $ 3.56      $13,277,219
Placement agent fees                                     $ 0.178     $   663,861
Proceeds, before expenses, to Cytogen                    $ 3.382     $12,613,358


We expect  total  offering  expenses,  including  placement  agent  fees,  to be
approximately $750,000 for all sales pursuant to the prospectus  supplemented by
this prospectus supplement.

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INVESTING IN OUR COMMON STOCK INVOLVES A HIGH DEGREE OF RISK. SEE "RISK FACTORS"
BEGINNING ON PAGE 4 OF THE PROSPECTUS.

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





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No  dealer,  salesperson  or any other  person has been  authorized  to give any
information  or make  any  representations  not  contained  in  this  prospectus
supplement or the prospectus, as previously supplemented, and, if given or made,
the  information  or  representations  must not be relied  upon as  having  been
authorized by us. This prospectus  supplement and the prospectus,  as previously
supplemented,  do not constitute an offer to sell, or a solicitation of an offer
to buy, any securities to any person in any jurisdiction  where such an offer or
solicitation  would  be  unlawful.  Neither  the  delivery  of  this  prospectus
supplement  or the  prospectus,  as previously  supplemented,  nor any sale made
hereunder or thereunder shall,  under any  circumstance,  create any implication
that the  information  contained  herein or  therein  is  correct as of any time
subsequent to the date hereof.


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This prospectus  supplement and the accompanying  prospectus,  dated November 5,
2004,  relate to the offer by us of up to  3,729,556  shares of our common stock
and warrants to purchase  1,118,867  shares of our common stock. You should read
this prospectus  supplement  along with the  accompanying  prospectus  carefully
before making a decision to invest in our common stock.  These documents contain
important  information you should consider when making your investment decision.
This prospectus  supplement contains  information about the common stock offered
hereby and the prospectus contains  information about our securities  generally.
This  prospectus  supplement  may  add,  update  or  change  information  in the
prospectus.  You should rely only on the information provided in this prospectus
supplement  and  the  accompanying   prospectus  or  documents  incorporated  by
reference  in the  accompanying  prospectus.  We have not  authorized  anyone to
provide you with any other information.

Issuance of Common Stock
------------------------

On December 13, 2005,  we entered into a securities  purchase  agreement for the
sale of an  aggregate  of  3,729,556  shares of our common stock and warrants to
purchase 932,389 shares of our common stock to certain  institutional  investors
for an aggregate  purchase price of  approximately  $13,300,000.  The prospectus
provides  for the sale of up to  $70,000,000  in  registered  securities  of our
common stock.
 
Terms of Warrants
-----------------

The warrants include the following terms:
 
      o   a term of five years;


      o   an exercise price of $4.25 per share;


      o   a cashless exercise provision; and


      o   the warrants  cannot be exercised  until six months  and one  day have
          elapsed from the date of issuance.


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                                                       THE OFFERING




                                                                       
Common stock offered in this offering:                       3,729,556 shares
                                                                     
Common stock underlying warrants:                            932,389 shares

Common stock underlying placement agent warrants:            186,478 shares
                                                                     
Common stock outstanding before this offering:               18,741,488 shares
                                                                     
Common stock to be outstanding after this offering:          22,471,044 shares
                                                                     
Use of proceeds:                                             See "Use of Proceeds" on page 24 of the prospectus.
                                                                     
Nasdaq National Market symbol:                               CYTO



The  information  above  is based  on  18,741,488  shares  of our  common  stock
outstanding as of September 30, 2005. It does not include:
 
      o   1,229,513  shares of our  common stock issuable  upon the  exercise of
          stock  options  outstanding  as of  September  30,  2005 at a weighted
          average exercise price of $8.067 per share;


      o   2,684,218  shares  of  common  stock  issuable  upon the  exercise  of
          warrants  outstanding  as of September 30, 2005 at a weighted  average
          exercise price of $9.78 per share; and


      o   601,924  shares of common stock  reserved for future  awards under our
          stock  incentive  plans and stock  purchase  plan as of September  30,
          2005.


In June 2005,  the Company  awarded an aggregate of 161,600 shares of restricted
common stock to employees of the Company  pursuant to the terms of the Company's
2004 Stock Incentive Plan. Such restricted  shares are subject to future vesting
and will be issued upon the  satisfaction  of such vesting  provisions and other
terms and conditions related thereto.


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                              PLAN OF DISTRIBUTION
 
We are offering the shares of common stock and the warrants  through a placement
agent. Rodman & Renshaw,  LLC have agreed to act as placement agent for the sale
of up to 3,729,556  shares of our common stock and warrants to purchase  932,389
shares of our common stock. The placement agent is not purchasing or selling any
shares by this prospectus  supplement and the accompanying  prospectus,  nor are
they  required to arrange the purchase or sale of any specific  number or dollar
amount of the shares,  but have agreed to use reasonable  efforts to arrange for
the sale of all  3,729,556  shares of common  stock and all warrants to purchase
932,389 shares of our common stock.
 
The placement  agent has arranged for the sale to one or more  purchasers of the
shares  of  common  stock  and  warrants  offered  pursuant  to this  prospectus
supplement and the accompanying  prospectus  through direct purchase  agreements
between  the  purchasers  and us.  We  will  pay the  placement  agents  a total
commission  equal to 5% of the gross  proceeds  of the sales of shares of common
stock and warrants and issue to the placement agent warrants to purchase 186,478
shares of our common stock.
 
The following table shows the per unit and total  commissions we will pay to the
placement agent in connection  with the sale of the shares and warrants  offered
pursuant to this prospectus supplement and the accompanying prospectus, assuming
the purchase of all of the shares offered hereby.


Per unit                                                         $     0.178
Maximum Offering Total                                           $   663,861

Our  obligation  to issue and sell  shares to the  purchasers  is subject to the
conditions  set forth in the purchase  agreements,  which may be waived by us in
our  discretion.  A  purchaser's  obligation  to  purchase  shares is subject to
conditions  set  forth in the  purchase  agreement  as well,  which  also may be
waived.
 
It is  expected  that the sale of  3,729,556  shares  of our  common  stock  and
warrants to purchase  932,389 shares of our common stock will be completed on or
about  December 14, 2005. We estimate the total  expenses of this offering which
will be payable by us, excluding the commissions, will be approximately $86,000.
 
We have agreed to indemnify the placement  agent  against  certain  liabilities,
including liabilities under the Securities Act of 1933, as amended.

The engagement agreement with Rodman & Renshaw, LLC is included as an exhibit to
our Current Report on Form 8-K/A that was filed with the Securities and Exchange
Commission in connection with this offering.
 
We have agreed to a 30-day  "lock up" with respect to shares of our common stock
and other of our securities,  including  securities  that are  convertible  into
shares of common stock and securities  that are  exchangeable or exercisable for
shares of common stock. This means that,  subject to certain  exceptions,  for a
period of 30 days following the date of this prospectus  supplement,  we may not
offer,  sell, pledge or otherwise dispose of these securities  without the prior
written consent of Rodman & Renshaw, LLC.

                                December 14, 2005



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