The article reports that the European Medicines Agency Phamacovigilance Risk Assessment Committee revealed that direct-acting antiviral agents applied for hepatitis C (HCV) treatment have a chance of causing reactivation of hepatitis B (HBV). Topics discussed include the committee recommendation for HBV diagnosis before treatment, treatment agents cited by the committee like daclatasvir, dasabuvir and simeprevir, and 30 cases of HBV reactivation were documented in Europe.