An expert review on the use of tenofovir alafenamide for the treatment of chronic hepatitis B virus infection in Asia

Abstract

Asia has intermediate-to-high prevalence and high morbidity of hepatitis B virus (HBV) infection. The use of guideline-recommended nucleos(t)ide analogs with high barrier to resistance, such as entecavir (ETV), tenofovir disoproxil fumarate (TDF), and tenofovir alafenamide (TAF), is one of the key interventions for curbing HBV infection and associated morbidity in Asia. However, there are some challenges to the use of ETV and TDF; while ETV is associated with high resistance in lamivudine (LAM)-exposed (especially LAM-refractory) patients; bone and renal safety issues are a major concern with TDF. Hence, a panel of twenty-eight expert hepatologists from Asia convened, reviewed the literature, and developed the current expert opinion-based review article for the use of TAF in the resource-constrained settings in Asia. This article provides a comprehensive review of two large, phase 3, double-blind, randomized controlled trials of TAF versus TDF in HBeAg-negative (study 0108) and HBeAg-positive (study 0110) chronic HBV patients (> 70% Asians). These studies revealed as follows: (1) non-inferiority for the proportion of patients who had HBV DNA < 29 IU/mL; (2) significantly high rate of normalization of alanine aminotransferase levels; (3) no incidence of resistance; and (4) significantly better bone and renal safety, with TAF vs. TDF up to 144 weeks. Considering the benefits of TAF, the expert panel proposed recommendations for optimizing the use of TAF in Asia, along with guidance on specific patient groups at risk of renal or bone disease suitable for TAF therapy. The guidance provided in this article may help clinicians optimize the use of TAF in Asia.

Demographics, Biochemical Characteristics, and Phases of Chronic Hepatitis B Virus Infection: Retrospective Analysis From a Secondary Care Setup

“…In their study, Buti et al did not record the loss of HBsAg at all in patients treated with either tenofovir or entecavir for 48 weeks [28]. Charlton et al and Aziz et al have reported analogous outcomes [29,30]. It was very unlikely that we would see a case of phase-V chronic HBV in such a small sample size where all patients were treatment-naive.…”

Clinical Features and Resistance to Entecavir Monotherapy of Patients with Hepatitis B

“…ETV is associated with resistance in LAM-experienced (particularly LAM-refractory) patients, and bone and renal safety issues are a concern with TDF [ 18 , 19 ]. Therefore, it has been proposed that optimizing the use of TAF is suitable for NA therapy along with guidance on specific patient groups at risk of renal or bone disease LAM-experienced patients [ 20 , 21 ]. As for ETV, it has a large number of accumulating evidences, usage experiences, and cost effectiveness.…”

Life-long passion for antiviral research and drug development: 80th birthday of Prof. Dr. Erik De Clercq

“…In these regimens, TDF is often combined with either emtricitabine or lamivudine plus other compounds [36] , [37] . However, bone and renal safety is the main concern with TDF in clinical practice [40] .…”