We read with great interest the article by Martinot-Peignoux et al.1 In this report from France, undetectable serum hepatitis C virus (HCV) RNA at 12 weeks (W+12) (409 patients) post-treatment follow-up was as relevant as undetectable serum HCV RNA at 24 weeks (W+24) (sustained virological response [SVR]; 408 patients) after the end of treatment.
Current standard therapy is based on a combination of pegylated interferon (PEG-IFN) and ribavirin, but it leads to only ∼50% SVR in patients with HCV genotype 1 and high viral loads.2 IFN reduced the risk for HCC, especially among patients with SVR.3, 4 Then, we need to accurately judge whether the patient is SVR or non-SVR, applying the present standard for the judgment of SVR with the undetectability of serum HCV RNA at post-treatment W+24.
We investigated 102 patients with chronic hepatitis C genotype 1 treated with PEG-IFN-alfa 2a plus ribavirin for 48 weeks. Some of these patients had already been included in previous reports.5, 6 Serum HCV RNA was measured using the COBAS TaqMan HCV test with a detection limit of 1.2 logIU/mL. At the W+24 post-treatment follow-up, 40 (39.2%) patients had SVR, and 31 (48.4%) and 9 (23.6%) were treatment naïve and previously treated patients, respectively. At W+12, serum HCV RNA was undetectable in 42 patients, and 40 patients were SVR (PPV, 95.2%). We found two relapsers at W+24 (undetectable at W+12).
In the case of using direct-acting antivirals, earlier knowledge of treatment outcome would be useful for retreatment for the same patient. Taken together, our findings show that W+12 undetectable serum HCV RNA is not suitable for predicting persistent virological response. Further understanding of the mechanism of relapse could be useful in reducing the post-treatment follow-up period from the current standard of 24 weeks.