Four weeks of off-treatment follow-up is sufficient to determine virologic responses at off-treatment week 12 in patients with hepatitis C virus infection receiving pangenotypic direct-acting antivirals

Abstract

Background: Early confirmation of sustained virologic response (SVR) or viral relapse after direct-acting antivirals (DAAs) for hepatitis C virus (HCV) infection is essential based on public health perspectives, particularly for patients with high risk of nonadherence to posttreatment follow-ups. Methods: A total of 1011 patients who achieved end-of-treatment virologic response, including 526 receiving pangenotypic DAAs, and 485 receiving genotype-specific DAAs, who had available off-treatment weeks 4 and 12 serum HCV RNA data to confirm SVR at off-treatment week 12 (SVR₁₂) or viral relapse were included in the analysis. The positive predictive value (PPV) and negative predictive value (NPV) of SVR₄ to predict patients with SVR₁₂ or viral relapse were reported. Furthermore, we analyzed the concordance rate between SVR₁₂ and SVR₂₄ in 943 patients with available SVR₂₄ data. Results: The PPV and NPV of SVR₄ to predict SVR₁₂ were 98.5% (95% confidence interval [CI]: 98.0%-98.9%) and 100% (95% CI: 66.4%-100%) in the entire population. The PPV of SVR₄ to predict SVR₁₂ in patients receiving pangenotypic DAAs was higher than those receiving genotype-specific DAAs (99.8% [95% CI: 98.9%-100%] versus 97.1% [95% CI: 96.2%-97.8%], p < 0.001). The NPVs of SVR₄ to predict viral relapse were 100%, regardless of type of DAAs. Moreover, the concordance rate between SVR₁₂ and SVR₂₄ was 100%. Conclusion: In patients with HCV who are treated with pangenotypic DAAs, an off-treatment week 4 serum HCV RNA testing is sufficient to provide an excellent prediction power of SVR or viral relapse at off-treatment week 12.