Examination of the long-term efficacy and safety of switching from entecavir to tenofovir alafenamide, including the anti-carcinogenic effect

Abstract This study evaluated the long-term efficacy and safety, as well as the anti-carcinogenic effects, of entecavir (ETV) and tenofovir alafenamide (TAF), which are widely used in Japan. The prospective observational analysis included 77 patients with chronic hepatitis B assigned to the ETV continuation and TAF change groups. After 240 weeks, the mean change in serum hepatitis B surface antigen (-0.365±0.069 log IU/mL vs. 0.301±0.039 log IU/mL, p=0.39) and estimated glomerular filtration rate (-5.407±1.660 vs. -2.666±1.52, p=0.240) did not differ significantly between the ETV and the TAF groups. Additionally, the levels of urinary β2-microglobulinβ/creatinine (2.330±0.374 at baseline vs. 2.335±0.257 at 240 weeks for ETV and 2.720±0.073 vs. 2.123±0.310 for TAF, p=0.996 and 0.455, respectively) or urinary N-acetyl-beta-D-glucosaminidase/creatinine (0.040±0.005 at baseline vs. 0.044±0.004 at 240 weeks for ETV and 0.049±0.005 vs. 0.053±0.005 for TAF, p=0.642 and 0.684, respectively) did not differ between the two groups. Finally, no significant difference was observed in the carcinogenesis inhibitory effect between the ETV and TAF groups (log-rank test, p=0.08). In conclusion, the long-term observation in the present study demonstrated the comparable efficacy and safety between ETV and TAF.