Viral kinetics during the first month of treatment in patients with genotype 1 chronic hepatitis C.

Objective: to identify predictive factors of response to pegylated interferon alpha-2b and ribavirin in patients with genotype 1 chronic hepatitis C. Viral kinetics were studied in weeks 2 and 4.
Methods: a prospective and consecutive study of patients with genotype 1 chronic hepatitis C referred to our Hepatology Clinic between January 2004 and October 2006 for antiviral treatment. Baseline data were recorded and viremia levels were determined hours before the weekly dose of pegylated interferon by qualitative and quantitative PCR.
Results: 57 patients were included in the study, although 3 of these were excluded during follow up; 65% were male (n = 35), with a mean age of 42 (26-65) years. Baseline viremia levels were > 800,000 IU/mL in 67% (n = 36). Liver biopsy was performed in 86% (n = 46), 22% (n = 12) had advanced fibrosis. Forty were naïve, 4 relapsing and 10 non-responders. Ribavirin dose was modified in one patient alone due to adverse effects. End treatment response and sustained virological response (SVR) were 59 and 41%, respectively. A univariate analysis revealed a statistically significant association of SVR with baseline viremia (p = 0.006), baseline GGT (p = 0.025), and a reduction in viremia > or =2 logs at 2, 4 and 12 weeks (p = 0.001). The extent of viremia reduction at week 2 was associated with 100% SVR, and at 4 weeks the positive predictive values was 84% and the negative predictive values was 96.5%. A subanalysis of the naïve group yielded analogous results.
Conclusions: in our study, a reduction in viremia > or = 2 logs 2 weeks after treatment could ensure SVR. At 4 weeks, most non-responders could be identified.