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) October 30, 2000
ENZON, INC.
(Exact name of registrant as specified in its charter)
Delaware 0-12957 22-237286
(State or other jurisdiction (Commission (IRS Employer
of 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
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(Former name or former address, if changed since last report)
Item 5. Other Events
Enzon Announces Schering-Plough Reports Results of Phase III Pivotal
PEG-INTRON(TM) PLUS REBETOL(R) Study
Enzon, Inc. announced today that Schering-Plough Corporation reported the
results of a pivotal Phase III clinical study, presented for the first time at
the Presidential Plenary Session of the 51st Annual Meeting of the American
Association for the Study of Liver Diseases (AASLD) in Dallas. The study showed
that combination therapy with once-weekly PEG-INTRON(TM) (peginterferon alfa-2b)
Injection plus daily REBETOL(R) (Ribavirin, USP) Capsules achieved a 54% rate of
sustained virologic response overall in previously untreated adult patients with
chronic hepatitis C. Sustained virologic response across hepatitis C virus
genotypes ranged from 42% to 82% in patients receiving PEG-INTRON plus REBETOL
combination therapy. When analyzed on an optimized dose/body-weight basis (>10.6
mg/kg of REBETOL daily), sustained virologic response was 61% for all genotypes,
48% for genotype 1 and 88% for genotypes 2 and 3. PEG-INTRON is a longer-acting
form of INTRON A that uses proprietary PEG technology developed by Enzon.
Sustained virologic response (SVR) is defined as sustained loss of detectable(1)
hepatitis C virus (HCV-RNA).
Results of the PEG-INTRON plus REBETOL study represent the largest and most
complete clinical data reported to date involving peginterferon and ribavirin
combination therapy. In all, PEG- INTRON was the subject of seven presentations
by study investigators at AASLD.
PEG-INTRON Plus REBETOL Combination Therapy
In an AASLD Presidential Plenary Session, study investigators presented
results of a pivotal Phase III clinical study designed to establish the activity
and tolerance of two dosing regimens of PEG-INTRON plus REBETOL compared to
REBETRON(TM) Combination Therapy containing REBETOL (Ribavirin, USP) Capsules
and INTRON(R) A (Interferon alfa-2b, recombinant) Injection, the current
standard of care, in previously untreated chronic hepatitis C patients. A total
of 1,530 patients from 62 sites worldwide (33 U.S., 5 Canada, 22 Europe, 2
Other) were randomized to three treatment arms:
(A) PEG-INTRON Injection 1.5 mcg/kg once weekly (QW) plus REBETOL Capsules 800
mg/daily for 48 weeks (PEG 1.5/R);
(B) PEG-INTRON 1.5 mcg/kg QW plus REBETOL 1000-1200 mg/daily for four weeks
followed by PEG-INTRON 0.5 mcg/kg QW plus REBETOL 1000-1200 mg/daily for 44
weeks (Peg 0.5/R); or
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(1) Defined as HCV-RNA below limit of detection using a research-based
RT-PCR assay.
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(C) INTRON A Injection 3 MIU/three times weekly plus REBETOL Capsules 1000-1200
mg/daily for 48 weeks (REBETRON).
The demographic/disease characteristics of patients in this study were
similar to those in previous Schering-Plough hepatitis C registration studies:
66% male; mean age 44 years; mean body weight 83 kg, pretreatment HCV-RNA (NGI
LLQ 100 copies/ml)>2 million copies 68%; and HCV genotype 1 (68%), genotypes 2
and 3 (29%), other genotypes (3%) (InnoLipa, Innogenetics).
Patients in the PEG 1.5/R arm achieved significantly higher SVR (54%)
overall compared to patients in the REBETRON arm (47%), while patients in the
PEG 0.5/R arm achieved numerically similar SVR (47%) to those receiving
REBETRON. When analyzed on a dose/body-weight basis (>10.6 mg/kg of REBETOL
daily), SVR was 61% overall for patients in the PEG 1.5/R arm, compared to 48%
for patients in the PEG 0.5/R arm and 47% for patients in the REBETRON arm.
Consistent with previous studies, the rates of sustained virologic response
in this study were greatly influenced by genotype, with patients in the PEG
1.5/R arm with genotype 1, the predominant genotype worldwide and the most
difficult to treat, achieving 42% SVR compared to 34% and 33% for patients in
the PEG 0.5/R arm and REBETRON arm, respectively. When analyzed on a
dose/body-weight basis (>10.6 mg/kg of REBETOL daily), patients in the PEG 1.5/R
arm with genotype 1 achieved 48% SVR compared to 34% for patients in both the
PEG 0.5/R arm and the REBETRON arm. Patients with genotypes 2 and 3 in these
treatment arms achieved 88%, 80% and 80% SVR, respectively.
The safety profile of both doses of PEG-INTRON plus REBETOL was similar to
that for REBETRON, with no new types of adverse events observed. Discontinuation
of therapy for adverse events was similar in all three treatment groups: PEG
1.5/R (14%), PEG 0.5/R (13%), REBETRON (13%), as was dose modifications, 42%,
36%, and 34%, respectively.
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PEG-INTRON PLUS REBETOL PIVOTAL PHASE III STUDY
(Sustained Virologic Response)
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RESULTS: (A) PEG 1.5/R (B) PEG 0.5/R (C) REBETRON A vs. C
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SVR (overall) 54% 47% 47% p=0.01
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SVR Genotype 1 42% 34% 33% p=0.02
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SVR Genotypes 2&3 82% 80% 79%
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Optimized Weight-Based Dosing
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(>10.6 mg/kg/daily REBETOL*)
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SVR (overall) 61% 48% 47%
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SVR Genotype 1 48% 34% 34%
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SVR Genotypes 2 & 3 88% 80% 80%
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PEG-INTRON
Additional PEG-INTRON presentations at AASLD included a study showing that
treatment with PEG-INTRON resulted in higher rates of sustained virologic
response in Black and Hispanic patients compared to standard alpha interferon
therapy. Another study with PEG-INTRON showed that sustained virologic response
is associated with marked improvement in hepatic inflammation and fibrosis, and
also showed that patients who do not achieve a sustained response, i.e. those
who relapse following treatment or who are nonresponders, also show improvement
in hepatic fibrosis. Study investigators suggested that further evaluation is
warranted to determine whether some patients may benefit from maintenance
therapy with PEG-INTRON.
A study presented by John B. Wong, M.D., Tufts University, New England
Medical Center, Boston, Mass., estimated the cost-effectiveness of PEG-INTRON
plus REBETOL for a range of possible trial outcomes as compared to REBETRON
Combination Therapy or no antiviral therapy. In his study, Wong concluded that
if trial results suggest that PEG-INTRON plus REBETOL increases the relative
rate of sustained virologic response, then 48 weeks of combination therapy with
PEG-INTRON plus REBETOL should provide good value for its clinical benefit.
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Except for the historical information herein, the matters discussed herein
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, Form 10-Qs and Form 8-K
on file with the SEC, including without limitation, risks in obtaining and
maintaining regulatory approval for expanded indications, market acceptance of
and continuing demand for Enzon's products and the impact of competitive
products and pricing.
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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: November 2, 2000
ENZON, INC.
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(Registrant)
By: /S/ KENNETH J. ZUERBLIS
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Kenneth J. Zuerblis
Vice President, Finance
and Chief Financial
Officer
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