Source Department of Hepatology, Osaka City University Graduate School of Medicine, Osaka Department of Virology and Liver Unit, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.
Aim: We evaluated the efficacy of response-guided therapy in patients with hepatitis C virus (HCV) genotype 2.
Methods: We studied 105 patients with an HCV genotype 2 load of higher than 5.0 Log IU/mL who received more than 75% of the target dose of pegylated interferon plus ribavirin. Among patients with rapid viral response (RVR; no HCV RNA detected at week 4), 14 selected 16 weeks of therapy (group A), and 28 selected 24 weeks of therapy (group B). Among non-RVR patients, 40 selected 24 weeks of therapy (group C), and 19 selected 48 weeks of therapy (group D).
Results: All patients in group A and B achieved a sustained viral response (SVR). Clinical characteristics did not differ significantly between groups C and D. However, the proportion of patients in whom HCV RNA disappeared at a later week after starting treatment was higher in group D (P = 0.0578). SVR rate was 73% in C, and 79% in D. Among patients in whom HCV RNA disappeared between weeks 5 and 8, SVR was achieved in 28 (82%) of 34 patients in C and 10 (91%) of 11 patients in D. Among patients whose HCV RNA disappeared between weeks 9 and 12, SVR was achieved in one (20%) of five patients in C and five (63%) of eight patients in D (not statistically significant).
Conclusions: 16 weeks of combination therapy could achieve an adequate antiviral effect for RVR patients. Extending therapy could not significantly improve SVR rate in non-RVR patients.