Efficacy and safety of peginterferon alfa-2a/ribavirin in methadone maintenance patients: randomized comparison of direct observed therapy and self-administration.

BACKGROUND: Adherence to chronic hepatitis C (CHC) treatment may be particularly challenging in methadone maintenance patients. We assessed the safety, tolerability, and efficacy of peginterferon alfa-2a/ribavirin treatment in methadone maintenance patients previously untreated for CHC. METHODS: Patients were randomized 1:1 to direct observed therapy (DOT) or self-administration (SA) of peginterferon alfa-2a. DOT patients were seen weekly at methadone clinics; SA patients were seen less frequently, only at investigative sites. Genotype 1-infected patients were treated for 48 wk with peginterferon alfa-2a (180 microg/wk)/ribavirin (1,000/1,200 mg/day); genotypes 2- and 3-infected patients were treated for 24 wk with peginterferon alfa-2a (180 microg/wk)/ribavirin (800 mg/day). RESULTS: Based on defined efficacy stopping rules, 77% (37/48) completed their targeted length of treatment, and 44% (21/48) achieved sustained virologic response (SVR). Two DOT and 3 SA patients were withdrawn for safety reasons and 6 and 9, respectively, for nonsafety reasons. Over 60% and 50% of each group were >80% compliant with the planned cumulative doses of peginterferon alfa-2a and ribavirin, respectively, and over 60% with overall treatment duration. SVR rates were 54% (13/24) for DOT and 33% (8/24) for SA; 23% (3/13) and 38% (6/16), respectively, for genotype 1 and 91% (10/11) and 25% (2/8), respectively, for genotypes 2 and 3. Stepwise logistic regression analysis, showed that DOT (vs SA; OR 3.27, 95% CI 0.90-11.91, P = 0.073) and Caucasian race (vs Other; OR 13.31, 95% CI 1.42-124.71, P = 0.023) were predictors of SVR. CONCLUSION: Peginterferon alfa-2a/ribavirin can be used safely and successfully in CHC patients receiving methadone maintenance.

Peginterferon-alpha2a and ribavirin combination therapy in chronic hepatitis C: a randomized study of treatment duration and ribavirin dose.

BACKGROUND: Treatment with pegylated interferon (peginterferon) and ribavirin for 48 weeks is more effective than conventional interferon and ribavirin in patients with chronic hepatitis C. OBJECTIVE: To assess the efficacy and safety of 24 or 48 weeks of treatment with peginterferon-alpha2a plus a low or standard dose of ribavirin. DESIGN: Randomized, double-blind trial. SETTING: 99 international centers. PATIENTS: 1311 patients with chronic hepatitis C. INTERVENTION: Peginterferon-alpha2a, 180 microg/wk, for 24 or 48 weeks plus a low-dose (800 mg/d) or standard weight-based dose (1000 or 1200 mg/d) of ribavirin. MEASUREMENT: Sustained virologic response: undetectable HCV RNA concentration at the end of treatment and during 12 to 24 weeks of follow-up. RESULTS: Overall and in patients infected with HCV genotype 1, 48 weeks of treatment was statistically superior to 24 weeks and standard-dose ribavirin was statistically superior to low-dose ribavirin. In patients with HCV genotype 1, absolute differences in sustained virologic response rates between 48 and 24 weeks of treatment were 11.2% (95% CI, 3.6% to 18.9%) and 11.9% (CI, 4.7% to 18.9%), respectively, between standard- and low-dose ribavirin. Sustained virologic response rates for peginterferon-alpha2a and standard-dose ribavirin for 48 weeks were 63% (CI, 59% to 68%) overall and 52% (CI, 46% to 58%) in patients with HCV genotype 1. In patients with HCV genotypes 2 or 3, the sustained virologic response rates in the 4 treatment groups were not statistically significantly different. CONCLUSION: Treatment with peginterferon-alpha2a and ribavirin may be individualized by genotype. Patients with HCV genotype 1 require treatment for 48 weeks and a standard dose of ribavirin; those with HCV genotypes 2 or 3 seem to be adequately treated with a low dose of ribavirin for 24 weeks.

A randomized trial of pegylated interferon alpha-2b plus ribavirin in the retreatment of chronic hepatitis C.

OBJECTIVES: The efficacy of combination therapy with pegylated interferon (PEG IFN) alpha plus ribavirin (RBV) in the retreatment of chronic hepatitis C (CHC) in patients who previously failed combination standard IFN plus RBV or IFN monotherapy has not been well established. METHODS: Three hundred and twenty-one CHC patients including virologic nonresponders to combination IFN plus RBV (n = 219) or IFN monotherapy (n = 47), and relapsers to combination therapy (n = 55) were randomized to receive PEG IFN alpha-2b 1.5 microg/kg per wk plus RBV 800 mg per day (Regimen A, n = 160) or PEG IFN alpha-2b 1.0 microg/kg per wk plus RBV 1,000-1,200 mg per day (Regimen B, n = 161) for 48 wks. RESULTS: Sustained virologic response (SVR) occurred in 16% of the overall study population (Regimen A vs B, 18%vs 13%, p= 0.21), in 8% of the combination therapy nonresponders (10%vs 6%, p= 0.35), in 21% of the IFN monotherapy nonresponders (16%vs 27%, p= 0.35), and in 42% of the combination therapy relapsers (50%vs 32%, p= 0.18). In nonresponders to prior combination therapy, HCV ribonucleic acid levels <100,000 copies/mL at the end of the prior treatment course were associated with an increased SVR compared with levels >or=100,000 copies/mL (21%vs 5%, p= 0.002). In the overall study population, genotype 1 patients had lower SVR rates than others (14%vs 33%, p= 0.01), and African Americans had lower SVR than Caucasians (4%vs 18%, p= 0.01). CONCLUSION: Combination therapy with PEG IFN alpha-2b plus RBV is more effective in patients who relapsed after combination standard IFN plus RBV than in nonresponders to either combination therapy or IFN monotherapy. There was no significant effect of dosing regimen.