To determine whether a higher dosage of interferon (IFN) associated with ribavirin and/or prolonged time of administration may improve therapeutic efficacy, we conducted a 4-arm randomized trial on patients with chronic hepatitis C not responding to one or more previous treatment courses with IFN monotherapy. Group 1 (n ؍ 139) received 3 million units (MU) IFN-␣2b 3 times a week (t.i.w.) plus ribavirin 1,000 mg/d for 12 months; group 2 (n ؍ 162) received 5 MU t.i.w. plus ribavirin for 12 months; group 3 (n ؍ 142) received 3 MU t.i.w. plus ribavirin for 6 months; and group 4 (n ؍ 151) received 5 MU t.i.w. plus ribavirin for 6 months. The primary end point was hepatitis C virus (HCV)-RNA clearance at the end of 6-month follow-up. HCV-RNA was negative in 15% of group 1, 23% of group 2, 11% of group 3, 16% of group 4 (group 2 vs. group 3, P ؍ .04). Among patients with genotypes 1 and 4, sustained response was significantly higher in group 2 vs. group 3 (18% vs. 7%, P ؍ .03; group 1 ؍ 9%, group 4 ؍ 12%, P ؍ not significant [NS]). In patients with genotypes 2 and 3, sustained virologic response was not affected by the different regimens (group 1 ؍ 32%, group 2 ؍ 30%, group 3 ؍ 30%, group 4 ؍ 35%, P ؍ NS). In conclusion, about 23% of nonresponders to IFN monotherapy may achieve a sustained response if Combination therapy (interferon [IFN] plus ribavirin) is the first-line therapy for naive patients with chronic hepatitis C 1,2 ; patients who have relapsed after an initial treatment with IFN alone can also be re-treated with good results. 3 Unfortunately, there is no therapeutic option for patients who have not responded to IFN and to date consensus conferences 4,5 have not recommended any therapeutic schedule for IFN nonresponders; these patients nevertheless represent a high percentage of patients.Re-treatment of nonresponders with higher dosages of IFN and/or more aggressive approaches is ineffective 5 or induces a low rate of sustained responders 6 ; recent trials with IFN plus ribavirin combination protocols 7-11 have given disappointing results, but the small number of patients recruited into the studies and the low dosage of IFN used have made the results questionable.To address the question of whether higher than standard IFN dosages associated with ribavirin and/or prolonged time of administration may improve the rate of sustained responses, we conducted a 4-arm randomized trial on patients with chronic hepatitis C not responding to one or more previous treatment courses with IFN alone. The study was designed to compare the efficacy and safety of IFN given at 3 million units (MU) and 5 MU 3 times a week (t.i.w.) plus ribavirin 1,000 mg given daily over treatment durations of 6 and 12 months.
PATIENTS AND METHODSDefinition of Nonresponse. According to the Consensus Conference held in Paris, February 26 to 27,1999, nonresponse to IFN monotherapy is defined by abnormal alanine transaminase (ALT) levels or by the presence of hepatitis C virus (HCV)-RNA during therapy; breakthroughs durin...