Background and purpose
Tenofovir alafenamide (TAF) demonstrated comparable efficacy and improved renal and bone safety to tenofovir disoproxil fumarate (TDF) in Chinese participants with chronic hepatitis B in two phase 3 trials. This study aimed to evaluate the long-term virological efficacy, serological and biochemical responses, tolerance, renal and bone safety of TAF over an 8-year period in this population.
method
Participants who completed the 3-year double-blind phase were eligible to receive open-label TAF 25 mg/day for up to an additional 5 years (8 years total). Analysis of viral suppression (HBV DNA < 29 IU/mL), alanine aminotransferase normalization, serological responses, resistance studies, and safety results were performed.
result
Of 334 enrolled participants, 212 of 227 participants randomized to TAF continued open-label TAF (TAF-TAF) and 99 of 107 TDF participants switched to open-label TAF (TDF-TAF). At year 8, 79.3% (180/227) and 78.5% (84/107) of participants in the TAF-TAF and TDF-TAF groups achieved viral suppression (missing = failure). After excluding missing data, the proportions increased to 95.2% (180/189) and 95.5% (84/88). Normalization rates for alanine aminotransferase remained high and comparable between groups. Serological response rates continued to increase over time, with higher response rates observed in the TAF-TAF group. Estimated glomerular filtration rate (according to Cockcroft-Gault) and hip/vertebral bone mineral density remained stable throughout the 8-year period in the TAF-TAF group. The slight decreases in these renal and bone parameters observed during double-blind TDF treatment were improved after switching to open-label TAF. No resistance to TAF was detected.
conclusion
This 8-year analysis provides strong evidence supporting the long-term efficacy and safety of TAF in Chinese CHB patients. Our study, the longest investigation of TAF in this population, not only confirms the good long-term renal and bone safety of TAF, but also demonstrates that the decline in renal and bone parameters associated with TDF may be reversible after switching to TAF. These findings are particularly relevant to China’s aging CHB population and strengthen the role of TAF as a preferred long-term treatment option.
sauce:
Reference magazines:
Hou, J. others. (2026). Eight-year results of two randomized phase III trials of tenofovir alafenamide for chronic hepatitis B virus infection in China. Journal of Clinical and Translational Hepatology. DOI: 10.14218/jcth.2025.00438. https://www.xiahepublishing.com/2310-8819/JCTH-2025-00438
