Kinetic of Virologic Response to Pegylated Interferon and Ribavirin in Children with Chronic Hepatitis C Predicts the Effect of Treatment

BACKGROUND:: Chronic hepatitis C is a global health problem. While new, highly effective and safe direct acting antivirals have been approved for adults, the only drugs currently registered for children are pegylated interferon and ribavirin. The timelines for the pediatric approval of the new treatment regimens are far off. Three phase II-III pediatric trials with direct acting antivirals are recruiting and the estimated dates of completion of these studies range between April 2018 and January 2023. METHODS:: The aim of the present prospective study was to evaluate the value of on-treatment virologic response (VR) as predictor of sustained virologic response (SVR) in a cohort of Italian children with chronic hepatitis C and to establish possible stopping rules. RESULTS:: Sixty-four children were enrolled (January 2012-December 2015). SVR rate was 79.7% (51/64). VR at weeks 2 to 12 were shown to be robust predictors for attainment of SVR. The positive predictive values of VR at weeks 8 and 12 were 98% and 92.7%, respectively. The negative predictive values at the same treatment weeks were 92.9% and 100%, indicating that no child who did not achieve VR at week 12 obtained SVR and that the likelihood of achieving SVR if still positive at week 8 was very low. CONCLUSIONS:: Our results suggest for the first time that VR at week 8 could be considered a reliable predictor of SVR. Monitoring viral kinetics is useful for predicting the success of pegylated interferon and ribavirin therapy in children.