Aim: To evaluate the significance of induction with high doses of pegylated interferon -2b (Peg-IFNalpha-2b) and the predictability of sustained virologic response (SVR) in naïve patients with chronic hepatitis C.
Methods: 188 consecutive naïve patients with chronic hepatitis C were enrolled in a randomised controlled clinical trial. Patients were randomised to receive either Peg-IFN -2b 3.0 mcg/kg QW x 12 weeks followed by 1.5 mcg/kg QW x 36 weeks plus 800-1200 mg ribavirin (Arm A) or Peg-IFNalpha-2b 1.5 mcg/kg QW x 48 weeks plus 800-1200 mg ribavirin (Arm B). HCV-RNA was obtained at 0, 4, 8, 12, 16, 24, 48 and 72 weeks. Differences between schemes were evaluated by Kaplan-Meier curves. Predictability of SVR was assessed by two-way contingency table analysis and ROC curve analysis.
Results: From 176 patients, 75 had genotype 1, 15 genotype 2, 75 genotype 3 and 11 genotype 4. No statistical significance emerged in HCV-RNA positivity, side effects and withdrawals between schemes. Patients with genotype 1 achieved lower SVR (46.6%) in comparison to patients with genotypes 2/3 (94.1%, p < 0.001) and 4 (90.9%, p = 0.002). The most appropriate time for estimation of SVR for genotype 1 is week 8 (accuracy = 0.84, AUC = 0.90) while predictability increases with time in genotypes 2/3, reaching maximum accuracy = 0.93 and AUC = 0.76 at week 16.
Conclusion: Induction with high doses of Peg-IFNalpha-2b does not preclude better outcome and rapid virologic response at 4 weeks of treatment sufficiently predicts SVR. These findings might be useful in an attempt to gain supportive evidence for decision making in difficult-to-treat patients.