SECURITIES AND EXCHANGE COMMISSION

                             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) August 13, 2001

                                   ENZON, INC.
             (Exact name of registrant as specified in its charter)

           Delaware                    0-12957                 22-2372868
(State or other jurisdiction of      (Commission              (IRS Employer
        incorporation)               File Number)            Identification)


                20 Kingsbridge Road, Piscataway, New Jersey 08854
               (Address of principal executive offices) (Zip Code)

       Registrant's telephone number, including area code: (732) 980-4500

                                       NA
          (Former name or former address, if changed since last report)






Item 5.  Other Events


             ENZON ANNOUNCES SCHERING-PLOUGH IN-LICENSING AGREEMENT
               WITH ROCHE RESOLVING PEGINTERFERON PATENT DISPUTES

     Enzon, Inc.  announced today that  Schering-Plough  (NYSE:SGP) has reported
that that it has entered into a licensing agreement with F.Hoffmann-La Roche Ltd
and Hoffmann-La Roche Inc., (Roche) that settles all patent disputes relative to
the two companies' respective peginterferon products. The agreement provides for
each company to manufacture and market worldwide its peginterferon products free
from liability for infringement under the other's existing patent rights.

     Under the agreement, Schering-Plough and Roche will seek court dismissal of
all  patent  litigation  in the  United  States  and  Europe  involving  the two
companies' respective peginterferon products. In addition, opposition to Roche's
European  peginterferon  patent,  filed by both  Schering-Plough  and Enzon, and
currently pending in the European Patent Office, will be withdrawn.

     Under terms of the agreement,  Schering-Plough and Roche will cross license
to each  other  all  patents  applicable  to their  pegylated  alpha  interferon
products,  PEG-INTRON(TM)  (peginterferon  alfa-2b)  and PEGASYS  (peginterferon
alfa-2a),  respectively.  In addition,  each party will license to the other its
patents applicable to peginterferon as combination therapy with ribavirin.

     The  settlement  agreement  also includes a  Schering-Plough  sublicense of
Enzon's  branched PEG patents (among  others) to Roche.  The sublicense of Enzon
patents pertains only to pegylated  versions of alpha interferon.  Consequently,
Enzon  has  agreed  to  dismiss  the  patent  infringement  lawsuit  it filed in
September 2000 against Roche asserting that PEGASYS  infringes  Enzon's branched
PEG patents.  However,  Enzon will continue to prosecute the patent infringement
lawsuit  it filed  in  December  1998,  against  Shearwater  Polymers  Inc.  for
infringement  of Enzon's  branched PEG patents based upon  Shearwater's  making,
using, and selling branched PEG reagents to parties other than Roche solely with
regard to Roche's peginterferon product, PEGASYS.





     In a June 1999  amendment to Enzon's  PEG-INTRON  licensing  agreement with
Schering-Plough,  Enzon had granted  Schering-Plough  a non-exclusive  worldwide
license, with a limited right to sublicense,  under Enzon's branched PEG patents
in  exchange  for an  increased  royalty  rate  on  Schering-Plough's  sales  of
PEG-INTRON.  The PEG-INTRON  licensing  agreement entitles Enzon to royalties on
worldwide sales of PEG-INTRON.

     In addition,  Schering-Plough will cooperate should Roche wish to acquire a
license from ICN Pharmaceuticals,  Inc. (NYSE: ICN) of Costa Mesa, Calif., under
patent  rights  to  oral   ribavirin  for  use  in   combination   with  Roche's
peginterferon product.  Currently,  Schering-Plough has exclusive license rights
under ICN's patents through a previous licensing agreement with ICN.

     Financial terms of the agreement are not being disclosed.  The agreement is
subject to the courts' dismissal of the relevant lawsuits.

     PEG-INTRON  is a  longer-acting  form of INTRON(R) A  (interferon  alfa-2b,
recombinant)  Injection that uses proprietary PEG technology developed by Enzon.
PEG-INTRON,   recombinant   interferon   alfa-2b   linked  to  a  12,000  dalton
polyethylene  glycol  (PEG)  molecule,  is a  once-weekly  therapy  designed  to
optimize  the balance  between  antiviral  activity and  elimination  half-life.
Schering-Plough  holds an exclusive  worldwide license to PEG-INTRON  granted by
Enzon.

     Except for the historical information herein, the matters discussed in this
Form 8-K include  forward-looking  statements that may involve a number of risks
and uncertainties.  Actual results may vary significantly based upon a number of
factors which are described in the Company's  Form 10-K/A,  Form 10-Q's and Form
8-Ks on file with the SEC, including without limitation,  risks in obtaining and
maintaining regulatory approval for indications and expanded indications, market
acceptance  of and  continuing  demand for  Enzon's  products  and the impact of
competitive products and pricing.







                                   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.

Dated: August 13, 2001

                                                         ENZON, INC.
                                             -----------------------------------
                                                         (Registrant)



                                             By: /s/ Kenneth J. Zuerblis
                                                 --------------------------
                                                 Kenneth J. Zuerblis
                                                 Vice President, Finance, Chief
                                                 Financial Officer and Secretary