Optimal follow-up time to determine the sustained virological response in patients with chronic hepatitis C receiving pegylated-interferon and ribavirin.

Background And Aim: This study evaluated whether the assessment of hepatitis C virus (HCV)-RNA at 12 weeks (FW+12) post-treatment follow-up was as applicable as FW+24 to evaluate sustained virological response (SVR) using the highly sensitive real-time polymerase chain reaction (PCR) HCV assay.

Methods And Results: Two hundred and twenty-two patients with chronic hepatitis C were included in this study. Pegylated interferon (Peg-IFN) and ribavirin were administered for 24-72 weeks based on the genotype and viral load. Serum HCV-RNA was measured using real-time PCR at pretreatment, the end of treatment, FW+4, FW+8, FW+12, FW+16, FW+20 and FW+24. Two hundred patients had a virological response at the end of treatment. One hundred and forty-eight of 200 (74.0%) patients with a virological response at the end of treatment had an SVR at the FW+24. The positive predictive value (PPV) to identify patients with SVR at FW+4, FW+8, FW+12 was 87.1, 96.1, 98.0%, respectively. The viral load showed a reversion to the basal level as early as 8 weeks in relapse patients. There were only three patients who relapsed after FW+12 and all three of these patients were females with genotype Ib and a high viral load.

Conclusion: The assessment of serum HCV-RNA FW+12, using the highly sensitive real-time PCR assay, is almost as effective as FW+24 to predict SVR. However, there are false negatives in female patients with a high viral load of genotype Ib when the SVR is predicted by FW+12. The current standard with FW+24 is reasonable, but the assessment of serum HCV-RNA FW+12 may be effective in most patients.