Monday January 22, 9:41 am Eastern Time
Press Release
Enzon Announces PEG-INTRON(tm) Receives
FDA Approval for the Treatment of Chronic
Hepatitis C
First Pegylated Interferon Approved for Marketing in the United States
PISCATAWAY, N.J.--(BUSINESS WIRE)--Jan. 22, 2001--Enzon, Inc. (NASDAQ:ENZN - news) announced today
that Schering-Plough Corporation (NYSE:SGP - news) has received U.S. Food and Drug Administration (FDA)
approval for PEG-INTRON(TM) (peginterferon alfa-2b) Powder for Injection as once-weekly monotherapy for the
treatment of chronic hepatitis C in patients not previously treated with alpha interferon who have compensated liver
disease and are at least 18 years of age.
PEG-INTRON is the first and only pegylated interferon approved for marketing in the United States. The product is
expected to be available nationwide in early February 2001.
PEG-INTRON is a longer acting form of Schering-Plough Corporation's INTRON® A that uses proprietary PEG
technology developed by Enzon. Under the Company's licensing agreement with Schering-Plough Corporation,
Enzon is entitled to royalties on worldwide sales of PEG-INTRON and milestone payments. This approval triggers
the final milestone payment of $2 million under the licensing agreement.
``While combination therapy with alpha interferon and ribavirin is a recognized standard of care for chronic hepatitis
C, PEG-INTRON monotherapy offers an alternative to patients whom combination therapy may be a contraindication
or who are intolerant of this therapy,'' said John G. McHutchison, M.D., medical director, liver transplantation,
division of gastroenterology and hepatology, Scripps Clinic and Research Foundation, La Jolla, Calif. ``As the first
pegylated interferon product approved for marketing, PEG-INTRON provides a valuable addition to the therapies
available to physicians for treating this serious disease,'' Dr. McHutchison said.
``We are pleased that our PEG technology will play such an important role in the treatment of patients afflicted with
this virus,'' said Peter G. Tombros, Enzon's president and chief executive officer. ``Schering-Plough's rapid
advancement of this product to the market offers evidence of the benefits that our PEG technology may provide to
compounds with delivery limitations.''
PEG-INTRON is administered subcutaneously once weekly for one year. The dose should be administered on the
same day of each week and may be self-administered by patients.
The safety and efficacy of PEG-INTRON has been demonstrated in a randomized, controlled clinical study involving
1,219 adult patients with chronic hepatitis C who were not previously treated with alpha interferon. The study
compared PEG-INTRON (0.5, 1.0 or 1.5 mcg/kg) administered subcutaneously once weekly to Schering-Plough's
INTRON® A (interferon alfa-2b, recombinant) Injection (3 MIU) administered subcutaneously three times weekly.
Patients were treated for 48 weeks and were followed for 24 weeks post-treatment. In the study, patients receiving
the 1.0 mcg/kg dose of PEG-INTRON achieved a 24 percent treatment response rate of sustained virologic response
and ALT(1) normalization as compared to a 12 percent treatment response rate in patients receiving INTRON A. The
safety and efficacy of PEG-INTRON in combination with ribavirin have not been established.
Nearly all study patients experienced one or more adverse events. The incidence of serious adverse events was
similar (about 12 percent) in all treatment groups. The most common adverse events associated with PEG-INTRON
were ``flu-like'' symptoms, which occurred in approximately 50 percent of patients; injection site irritation or
inflammation, seen in 47 percent of patients; and depression, seen in 29 percent of patients.
WARNING
Alpha interferons, including PEG-INTRON, cause or aggravate fatal or life-threatening neuropsychiatric,
autoimmune, ischemic and infectious disorders. Patients should be monitored closely with periodic clinical and
laboratory evaluations. Patients with persistently severe or worsening signs or symptoms of these conditions
should be withdrawn from therapy. In many but not all cases these disorders resolve after stopping PEG-INTRON
therapy.
PEG-INTRON, recombinant interferon alfa-2b linked to a 12,000 dalton polyethylene glycol (PEG) molecule, is a
once-weekly product designed to optimize the balance between antiviral activity and elimination half-life.
Schering-Plough holds an exclusive worldwide license to PEG-INTRON. Schering-Plough markets the product as
PEGINTRON(TM) in the European Union, where it received marketing approval in May 2000.
INTRON A is a recombinant version of naturally occurring alpha interferon, which has been shown to exert both
antiviral and immunomodulatory effects. Schering-Plough markets INTRON A, the world's largest-selling alpha
interferon, for 16 major antiviral and anticancer indications worldwide.
Some 4 million Americans are infected with the hepatitis C virus (HCV) and approximately 70 percent of infected
patients go on to develop chronic liver disease, according to the Centers for Disease Control and Prevention (CDC).
Hepatitis C infection contributes to the deaths of an estimated 8,000 to 10,000 Americans each year. This toll is
expected to triple by the year 2010 and exceed the number of annual deaths due to AIDS, according to the CDC. The
CDC has reported that HCV-associated end-stage liver disease is the most frequent indication for liver
transplantation among adults.
(1) ALT: alanine aminotransferase, an enzyme that indicates ongoing liver inflammation. |
