SUMMARY
REBETOL is Schering Corporation's brand name for ribavirin, a nucleoside analog with antiviral activity.
REBETOL (ribavirin, USP) Capsules is indicated in combination with INTRON A (interferon alfa-2b, recombinant) Injection for the treatment of chronic hepatitis C in patients with compensated liver disease previously untreated with alpha interferon or who have relapsed following alpha interferon therapy.
Previously Untreated Patients Adults with compensated chronic hepatitis C and detectable HCV RNA (assessed by a central laboratory using a research-based RT-PCR assay) who were previously untreated with alpha interferon therapy were enrolled into two multicenter, double-blind trials (US and International) and randomized to receive REBETOL Capsules 1200 mg/day (1000 mg/day for patients weighing </=75 kg) plus INTRON A Injection 3 MIU TIW or INTRON A Injection plus placebo for 24 or 48 weeks followed by 24 weeks of off-therapy follow-up. The International study did not contain a 24-week INTRON A plus placebo treatment arm. The US study enrolled 912 patients who, at baseline, were 67% male, 89% caucasian with a mean Knodell HAI score (I+II+III) of 7.5, and 72% genotype 1. The International study, conducted in Europe, Israel, Canada, and Australia, enrolled 799 patients (65% male, 95% caucasian, mean Knodell score 6.8, and 58% genotype 1).
Study results are summarized in TABLE 3.
TABLE 3. Virologic and Histologic Responses: Previously Untreated Patients *
|
|
US Study
|
International Study
|
24 weeks
of treatment
|
48 weeks
of treatment
|
24 weeks
of treatment
|
48 weeks
of treatment
|
INTRON A
plus
REBETOL
(N=228) |
INTRON A
plus
Placebo
(N=231) |
INTRON A
plus
REBETOL
(N=228) |
INTRON A
plus
Placebo
(N=225) |
INTRON A
plus
REBETOL
(N=265) |
INTRON A
plus
REBETOL
(N=268) |
INTRON A
plus
Placebo
(N=266) |
Virologic
Response |
|
-Responder1 |
65 (29) |
13 (6)
|
85 (37) |
27 (12) |
86 (32) |
113 (42) |
46 (17) |
|
-Nonresponder
|
147 (64) |
194 (84) |
110 (48) |
168 (75) |
158 (60) |
120 (45) |
196 (74) |
|
-Missing data
|
16 (7)
|
24 (10) |
33 (14) |
30 (13) |
21 (8)
|
35 (13) |
24 (9)
|
Histologic
Response |
|
-Improvement2 |
102 (45) |
77 (33) |
96 (42) |
65 (29) |
103 (39) |
102 (38) |
69 (26) |
|
-No improvement
|
77 (34) |
99 (43) |
61 (27) |
93 (41) |
85 (32) |
58 (22) |
111 (41) |
|
-Missing data
|
49 (21) |
55 (24) |
71 (31) |
67 (30) |
77 (29) |
108 (40) |
86 (32) |
|
*Number (%) of patients
|
| 1 Defined as HCV RNA below limit of detection using a research-based RT-PCR assay at end of treatment and during follow-up period.
|
| 2 Defined as posttreatment (end of follow-up) minus pretreatment liver biopsy Knodell HAI score (I+II+III) improvement of >/=2 points. |
|
Of patients who had not achieved HCV RNA below the limit of detection of the research-based assay by week 24 of REBETOL/INTRON A treatment, less than 5% responded to an additional 24 weeks of combination treatment.
Among patients with HCV genotype 1 treated with REBETOL/INTRON A therapy who achieved HCV RNA below the detection limit of the research-based assay by 24 weeks, those randomized to 48 weeks of treatment had higher virologic responses compared to those in the 24-week treatment group. There was no observed increase in response rates for patients with HCV nongenotype 1 randomized to REBETOL/INTRON A therapy for 48 weeks compared to 24 weeks.
Relapse Patients Patients with compensated chronic hepatitis C and detectable HCV RNA (assessed by a central laboratory using a research-based RT-PCR assay) who had relapsed following one or two courses of interferon therapy (defined as abnormal serum ALT levels) were enrolled into two multicenter, double-blind trials (US and International) and randomized to receive REBETOL 1200 mg/day (1000 mg/day for patients weighing </=75 kg) plus INTRON A 3 MIU TIW or INTRON A plus placebo for 24 weeks followed by 24 weeks of off-therapy follow-up. The US study enrolled 153 patients who, at baseline, were 67% male, 92% caucasian with a mean Knodell HAI score (I+II+III) of 6.8, and 58% genotype 1. The International study, conducted in Europe, Israel, Canada, and Australia, enrolled 192 patients (64% male, 95% caucasian, mean Knodell score 6.6, and 56% genotype 1).
Study results are summarized in TABLE 4.
TABLE 4. Virologic and Histologic Responses: Relapse Patients *
|
|
US Study
|
International Study
|
INTRON A
plus
REBETOL
(N=77) |
INTRON A
plus
Placebo
(N=76) |
INTRON A
plus
REBETOL
(N=96) |
INTRON A
plus
Placebo
(N=96) |
Virologic
Response |
|
-Responder1 |
33 (43) |
3 (4) |
46 (48) |
5 (5) |
|
-Nonresponder
|
36 (47) |
66 (87) |
45 (47) |
91 (95) |
|
-Missing data
|
8 (10) |
7 (9) |
5 (5) |
0 (0) |
Histologic
Response |
|
-Improvement2 |
38 (49) |
27 (36) |
49 (51) |
30 (31) |
|
-No improvement
|
23 (30) |
37 (49) |
29 (30) |
44 (46) |
|
-Missing data
|
16 (21) |
12 (16) |
18 (19) |
22 (23) |
|
*Number (%) of patients
|
| 1 Defined as HCV RNA below limit of detection using a research-based RT-PCR assay at end of treatment and during follow-up period.
|
| 2 Defined as posttreatment (end of follow-up) minus pretreatment liver biopsy Knodell HAI score (I+II+III) improvement of >/=2 points. |
|
Virologic and histologic responses were similar among male and female patients in both the previously untreated and relapse studies.
|
NEWS HIGHLIGHTSMedia Articles Related to Rebetol Intron A (Ribavirin)
InterMune Announces Modification To On-Going Phase 2b Study Of ITMN-191 In Patients With Chronic HCV Infection Source: Liver Disease / Hepatitis News From Medical News Today [2009.11.18] InterMune, Inc. (Nasdaq: ITMN) announced that the on-going Phase 2b study conducted by Roche of ITMN-191 (RG7227) combined with standard of care (SOC) PEGASYS® (peginterferon alfa-2a) and COPEGUS® (ribavirin) in HCV treatment-naive patients has been modified. The Phase 2b study has four dosage cohorts: SOC; 300mg q8h plus SOC; 600mg q12h plus SOC and 900mg q12h plus SOC. To date, approximately 175 patients have been enrolled in the study.
AASLD: Treating Before Transplant Cuts HCV Recurrence (CME/CE) Source: MedPage Today Gastroenterology [2009.11.06] BOSTON (MedPage Today) -- In patients with advanced liver disease related to hepatitis C, a course of pegylated interferon and ribavirin (Rebetol) before liver transplant may help them avoid recurrence of infection, a researcher said here.
SCYNEXIS' SCY-635 Demonstrates Positive Antiviral Activity In Combination With Approved And Investigational Anti-HCV Agents Source: Liver Disease / Hepatitis News From Medical News Today [2009.11.04] Drug discovery company SCYNEXIS, Inc. presented positive data from an in vitro study evaluating the antiviral activity of SCY-635 in combination with approved and investigational non-nucleoside polymerase inhibitors, nucleoside polymerase inhibitors, protease inhibitors, ribavirin and interferon alpha 2b. SCY-635 exhibited additive to synergistic antiviral activity when combined with each of the six compounds tested and all combinations exhibited greater-than-anticipated antiviral activity.
Bristol-Myers Squibb And ZymoGenetics Present Final Phase 1b Results For PEG-Interferon Lambda In Hepatitis C Source: Liver Disease / Hepatitis News From Medical News Today [2009.11.03] Bristol-Myers Squibb Company (NYSE: BMY) and ZymoGenetics, Inc. (NASDAQ: ZGEN) today presented final results from a Phase 1b clinical trial of PEG-Interferon lambda administered with ribavirin in relapsed and treatment-naïve hepatitis C virus (HCV) patients. The poster included data on 56 patients in the study. Antiviral activity was observed at all dose levels tested.
Schering-Plough Reports Potent Antiviral Activity With Narlaprevir (SCH 900518), An Investigational, Once-Daily Protease Inhibitor For Hepatitis C Source: Liver Disease / Hepatitis News From Medical News Today [2009.11.03] Schering-Plough Corporation (NYSE: SGP) reported that interim results from an ongoing Phase IIa study of narlaprevir (SCH 900518), its investigational, once-daily protease inhibitor, demonstrated potent antiviral activity in treatment-naive patients with chronic hepatitis C virus (HCV) genotype 1.
Published Studies Related to Rebetol Intron A (Ribavirin)
A phase III study of the safety and efficacy of viramidine versus ribavirin in treatment-naive patients with chronic hepatitis C: ViSER1 results. [2009.09] Pegylated interferon (peg-IFN) and ribavirin (RBV) are effective in eradicating the hepatitis C virus in more than half of patients. However, anemia arising from RBV-induced hemolysis can prompt dose reductions and lower sustained virologic response (SVR) rates... These results suggest fixed-dose VRD given 600 mg BID is insufficient to treat patients with chronic hepatitis C; a weight-based dosing trial of viramidine is currently under way.
Peginterferon alfa-2b or alfa-2a with ribavirin for treatment of hepatitis C infection. [2009.08.06] BACKGROUND: Treatment guidelines recommend the use of peginterferon alfa-2b or peginterferon alfa-2a in combination with ribavirin for chronic hepatitis C virus (HCV) infection. However, these regimens have not been adequately compared... CONCLUSIONS: In patients infected with HCV genotype 1, the rates of sustained virologic response and tolerability did not differ significantly between the two available peginterferon-ribavirin regimens or between the two doses of peginterferon alfa-2b. (ClinicalTrials.gov number, NCT00081770.) 2009 Massachusetts Medical Society
Predictability of sustained virological response to pegylated interferon alpha-2b Plus ribavirin therapy by week-8 viral response in HIV-positive patients with chronic hepatitis C virus infection. [2009.07] Chronic hepatitis C is frequent and aggressive in HIV-positive patients. Identification of early predictors of response to anti-HCV therapy is needed for a lower rate of response and higher discontinuations, compared to HCV mono-infected subjects...
Retreating chronic hepatitis C with daily interferon alfacon-1/ribavirin after nonresponse to pegylated interferon/ribavirin: DIRECT results. [2009.06] CONCLUSION: Retreatment of PEG-IFN and RBV nonresponders with CIFN and RBV is safe and efficacious and can be considered a retreatment strategy for patients failing previous therapy with PEG-IFN/RBV, especially in interferon-sensitive patients with lower baseline fibrosis scores.
Randomized trial of high-dose interferon-alpha-2b combined with ribavirin in patients with chronic hepatitis C: Correlation between amino acid substitutions in the core/NS5A region and virological response to interferon therapy. [2009.04] The aim of this study was to compare the efficacy of high-dose interferon (IFN)-alpha-2b with standard dose of IFN-alpha-2b in combination with ribavirin (RBV) for patients with chronic hepatitis C virus (HCV) infection, and to investigate the predictive factors associated with virological response...
Clinical Trials Related to Rebetol Intron A (Ribavirin)
Peg-Ifn Dose Evaluations for Previously Untreated Subjects With Chronic Hepatitis C Infected With Genotype 1 (Study P03471AM1)(COMPLETED) [Completed]
The objective is to compare the safety and efficacy of the following three treatment regimens
in previously untreated adult subjects with chronic hepatitis C infected with Genotype 1: (1)
PEG-Intron 1. 5 µg/kg/wk in combination with weight based REBETOL (800-1400 mg/day); (2)
PEG-Intron 1µg/kg/wk in combination with weight based REBETOL (800-1400 mg/day); and (3)
PEGASYS 180 µg/wk plus COPEGUS 1000-1200 mg/day.
Extended Treatment With PEG-Intron and Rebetol in Patients With Genotype 1 Chronic Hepatitis C and Slow Virologic Response (Study P03685AM3) [Active, not recruiting]
This is a controlled, randomized, parallel-groups, open-label, multinational study designed
to evaluate the efficacy and safety of PEG-Intron plus Rebetol in subjects with chronic
hepatitis C. It is designed to evaluate whether 72 weeks of treatment with PEG-Intron plus
Rebetol is more effective than 48 weeks of treatment in subjects with Genotype 1 chronic
hepatitis C who exhibit a slow response to treatment.
Peg-Intron and Rebetol Therapy in Treatment of Naive Hepatitis C Patients: A Comparison of Race and Genotype on Treatment Outcome (Study P04212)(COMPLETED) [Completed]
This is a multicenter clinical trial designed to compare the efficacy of 48 weeks of therapy
with pegylated (PEG)-Interferon/ribavirin in Southeastern Asian patients with genotype 1
chronic hepatitis C with 48 weeks of therapy with PEG-Interferon/ribavirin in Caucasian
patients with genotype 1 chronic hepatitis C. This study is also designed to provide a
randomized comparison of 24 weeks versus 48 weeks of therapy with PEG-Interferon/ribavirin in
Southeastern Asian patients with genotypes 6-9. The primary endpoint is sustained virologic
response, as defined by negative hepatitis C virus (HCV) ribonucleic acid (RNA) in serum at
24 weeks after therapy completion.
PEG-Interferon a-2b + Ribavirin for Treatment of Patients With Chronic Hepatitis C Who Have Previously Failed to Achieve a Sustained Virologic Response Following Interferon Alfa or Interferon a-2b + Ribavirin Therapy [Completed]
HRN-003 STUDY SYNOPSIS
OBJECTIVE: To compare the Sustained Virologic Response (SVR) of PEGIntron plus ribavirin
among patients receiving a fixed dose of PEGIntron versus weighted-adjusted dosing.
OVERVIEW OF STUDY DESIGN: This is a multi-center, randomized, open-label clinical trial using
PEGIntron weight-adjusted dose by subcutaneous injection weekly + ribavirin by mouth twice
daily for 48 weeks OR PEGIntron fixed dose by subcutaneous injection weekly + ribavirin by
mouth twice daily for 48 weeks.
STUDY POPULATION: 600 Adult patients with chronic hepatitis C virus infection who have
previously failed to achieve a sustained virologic response following interferon alfa or
interferon alfa-2b plus ribavirin therapy.
DOSAGE AND ADMINISTRATION: Eligible participants will be randomized to receive PEGIntron
weight-adjusted dose (1. 5 mg/kg) by subcutaneous injection weekly + ribavirin 400 mg by mouth
twice daily for 48 weeks OR PEGIntron fixed dose (150 mg if weight > than 80 kg or 100 mg if
weight < 80 KG) by subcutaneous injection weekly + ribavirin 400 mg by mouth twice daily for
48 weeks.
EFFICACY EVALUATIONS: Laboratory analysis, quality of life assessments, and change in study
medication doses will be obtained.
SAFETY EVALUATIONS: Assessment of laboratory evaluations, vital signs, incidence and severity
of adverse experiences and progression of disease, as measured by HCV viral load.
STUDY DESIGN
This is a treatment protocol to evaluate the antiviral efficacy, safety and tolerability
polyethylene glycol (PEG) conjugated interferon alfa-2b (PEGIntron) for the treatment of
chronic hepatitis C virus infection in patients who have previously failed to achieve a
sustained virologic response following interferon alfa or interferon alfa-2b plus ribavirin
therapy. Patients will be stratified according to their response to the previous course of
therapy (i. e. non-reponse or relapse virologic pattern
This is a multi-center, randomized, open-label clinical trial that will involve approximately
25 sites with an anticipated enrollment of 600 patients over a six-month period.
Eligible participants will be randomized to receive PEGIntron weight-adjusted dose (1. 5
mg/kg) by subcutaneous injection weekly + ribavirin 400 mg by mouth twice daily for 48 weeks
OR PEGIntron fixed dose (150 mg if weight > than 80 kg or 100 mg if weight < 80 KG) by
subcutaneous injection weekly + ribavirin 400 mg by mouth twice daily for 48 weeks.
- Group A: PEGIntron weight -adjusted dose (1. 5 mg/kg) by subcutaneous injection weekly
+ ribavirin 400 mg by mouth twice daily for 48 weeks (Total therapy x 48weeks).
- Group B: PEGIntron fixed dose (150 mg if weight > than 80 kg or 100 mg if weight < 80
KG) by subcutaneous injection weekly + ribavirin 400 mg by mouth twice daily for an
additional 48 weeks (Total therapy x 48 weeks).
REPEAT Study - A Study of PEGASYS (Peginterferon Alfa-2a (40KD)) Therapy in Combination With COPEGUS (Ribavirin) in Patients With Chronic Hepatitis C (CHC) Who Did Not Respond to Previous PegIntron (Peginterferon Alfa-2b (12KD))/Ribavirin Combination Therapy [Completed]
This 4 arm study is designed for patients with CHC who have not responded to peginterferon
alfa-2b (12KD)/ribavirin combination therapy. In these patients, the effects of lengthening
the duration of treatment, as well as including an initial 12-week period of high-dose
PEGASYS (360 micrograms sc), are compared with the standard combination therapy of PEGASYS
(180 micrograms sc) and ribavirin (1000-1200mg po). The anticipated time on study treatment
is 1-2 years and the target sample size is 500+ individuals.
|