Although there existed no association between the extent of reduction in serum HBsAg levels and those in serum ALT and AST levels both during the ETV treatment period and the TAF treatment period, serum AST levels at the time of the drug switching were higher in the TAF responders than in the remaining patients (18 vs. 15 U/L, P = 0.033), and the percentages of men and patients with underlying cirrhosis tended to be higher in the TAF responder group as compared to the remaining patients (P = 0.061 and P = 0.055, respectively). This evidence concerns the gene GPT and Cirrhosis.