Review article: switching patients with chronic hepatitis B to tenofovir alafenamide—a review of current data

Abstract

Summary Background The nucleos(t)ide analogues (NAs) entecavir (ETV), tenofovir disoproxil fumarate (TDF) and tenofovir alafenamide (TAF) are preferred treatment options for patients with chronic hepatitis B infection (CHB). However, resistance to ETV has been reported, especially with prior exposure to other NAs, and long‐term TDF treatment has been associated with decline in renal function and loss of bone mineral density in some patients. Consequently, TAF may be preferable to ETV, TDF or other NAs in specific circumstances such as in patients with risk of bone or renal complications, elderly patients or those with previous NA experience. Aim To provide a summary of the available efficacy and safety data following switch to TAF from other NAs in patients with CHB in clinical studies and real‐world settings. Methods Literature searches were performed on PubMed and abstracts from three major international liver congresses between 2019 and 2021. Studies that included efficacy and/or safety data for patients with CHB switching from any NA to TAF were selected. Results Thirty‐six papers and abstracts were included in this narrative review. Switching from TDF to TAF maintained or improved virological and biochemical responses with improved bone and renal safety. Switching from ETV or other NAs to TAF maintained or improved virological and biochemical responses and varying results for bone and renal safety. Conclusions Switching to TAF appears to maintain or improve virological, biochemical and bone‐ and renal‐related safety outcomes. These data support the concept of switching to TAF in some patients with CHB based on their individual circumstances.

Editorial: doesTAFhave a better or worse safety profile thanTDF, to treat hepatitis B?

“…Dr Young‐Suk et al 1 have analysed the effect of switching to tenofovir alafenamide (TAF) from tenofovir disoproxil fumarate (TDF), and entecavir (ETV). Normally, systematic reviews include three key conditions to ensure reliability.…”

Editorial: does TAF have a better or worse safety profile than TDF, to treat hepatitis B? Authors' reply

“…We thank Dr Hill for providing his thoughtful discussion on our narrative review of data related to switching patients with chronic hepatitis B (CHB) to tenofovir alafenamide (TAF). 1,2 As highlighted by Dr Hill, this is not a systematic review, but summarises data from clinical trial and real-world settings to provide an overview of how TAF is being used in clinical practice and the efficacy and safety profiles observed following switch. There is value in conducting systematic reviews given the stringent criteria applied; however, when compared with HIV, there are limited data available with TAF in CHB: 330 patients were switched from tenofovir disoproxil fumarate (TDF) to TAF in CHB clinical trials, 3,4 whereas the meta-analysis cited by Dr Hill in HIV included 2809 subjects.…”

“…6 A consequence of these recommendations is that many of the real-world studies included in the review focus on these parameters when reporting safety data. 1 However, where available, additional safety data are described, including lipids.…”

“…The authors' declarations of personal and financial interests are unchanged from those in the original article. 1…”

“…The significantly smaller reductions in bone mineral density and improvements in renal function seen in CHB trials 3,7,8 resulted in guidelines recommending TAF or entecavir over TDF in specific circumstances, including in patients at risk of renal or bone complications 6 . A consequence of these recommendations is that many of the real‐world studies included in the review focus on these parameters when reporting safety data 1 . However, where available, additional safety data are described, including lipids.…”