Gamma-glutamyltransferase and rapid virological response as predictors of successful treatment with experimental or standard peginterferon-alpha-2b in chronic hepatitis C non-responders.

ABSTRACT

BACKGROUND: High-dose peginterferon-alpha (PegIFN-alpha) induction and prolongation of therapy may be an option to improve sustained virological response (SVR) rates among hepatitis C virus (HCV) non-responders, although a higher and a longer dosing of PegIFN-alpha may intensify side effects. METHODS: We randomized 53 patients, who previously failed with standard IFN-alpha+/-ribavirin, to a high-dose induction and an extended regimen with PegIFN-alpha-2b [3.0 microg/kg once weekly (q.w.) 12 weeks-->2.0 microg/kg q.w. 12 weeks-->1.5 microg/kg q.w. 48 weeks] or a standard regimen (1.5 microg/kg q.w. 48 weeks). All patients received daily weight-based ribavirin (800-1200 mg/day). The short-form 36 health survey was used to evaluate health-related quality of life (HRQL). RESULTS: Intention-to-treat analysis showed no significant difference in SVR rate (44% vs. 37%, P=0.62) and relapse rate (9% vs. 31%, P=0.17) between experimental and standard treatment. Overall, 80% of the [positive predictive value (PPV)] patients with rapid virological response (RVR, HCV-RNA negativity at week 4) achieved SVR. No significant dose-related differences in HRQL were seen between both groups. At baseline, genotype 2 or 3 [odds ratio (OR) 7.4, 95% confidence interval (CI) 1.4-33.3, P=0.01] and gamma-glutamyltransferase (GGT) levels <2 x ULN (upper limit of normal) (OR 6.76, 95% CI 1.5-31.3, P=0.009) were significantly associated with SVR. Multivariate logistic regression at week 4 showed that only baseline GGT <2 x ULN (OR 7.3, 95% CI 1.4-38.5, P=0.01) and RVR (OR 15.6, 95% CI 3.2-76.9, P<0.001) were independently predictive for SVR. CONCLUSION: Retreatment with PegIFN-alpha-2b and ribavirin for a minimum of 48 weeks should be considered in all patients unresponsive to previous IFN-based therapies. Baseline GGT values and RVR are highly predictive for retreatment outcome.