Safety of current antiviral drugs for chronic hepatitis B

Introduction Oral nucleos(t)ide analogues (NUCs) are recommended as first-line therapy for chronic hepatitis B (CHB) due to higher HBV-DNA suppression rates and safety profile. Long-term treatment with NUCs is often necessary to achieve durable viral suppression. Areas covered This review provides an overview of the long-term safety data that have become available since entecavir (ETV) and tenofovir disoproxil fumarate (TDF) were first approved, and recent data on tenofovir alafenamide (TAF) in patients with CHB. Expert opinion NUCs generally show remarkable safety in patients taking them for long periods. Nevertheless, renal and bone toxicity may occur in a minority of patients on TDF therapy. These effects have been overcome by the recent release of TAF. Moreover, the currently available data do not allow firm conclusions on the superiority of TDF on ETV about hepatocellular carcinoma (HCC) risk reduction. Observational studies involving more homogeneous cohorts are therefore needed; furthermore, long-term studies assessing the impact of TAF on this important topic are warranted.