[Effect of switching from entecavir to tenofovir amibufenamide on HBsAg levels in patients with chronic hepatitis B: a 96-week real-world study].

Objective: To investigate the effect of switching from entecavir (ETV) to tenofovir amibufenamide (TMF) on hepatitis B surface antigen (HBsAg) levels in patients with chronic hepatitis B. Methods: Patients with chronic hepatitis B were enrolled and assigned to two groups after 48 weeks of ETV therapy. One group continued ETV treatment, whereas the other group switched to TMF. HBsAg levels were compared between the two groups of patients after continuous follow-up through week 96. Treatment efficacy was evaluated based on virological response, serological markers, and others. Independent-samples t-tests, repeated-measures analysis of variance (ANOVA), and the Mann-Whitney U test were used to compare continuous variables, while the χ2 test was used to compare categorical variables between the groups. Results: Seventy-eight patients in the ETV-continuation group and seventy-four in the ETV-to-switch-TMF group completed the 96-week follow-up. There were no statistically significant differences in hepatitis B surface antigen levels (HBsAg), hepatitis B e antigen (HBeAg) status, or hepatitis B virus (HBV) DNA levels between the two groups at baseline and 48 weeks (P>0.05). HBsAg levels decreased from (2.99±0.85) log10 IU/mL to (2.82±0.88) log10 IU/mL over 96 weeks in the ETV-continuation group (P=0.500). HBsAg levels dropped from (3.12±0.74) log10 IU/mL to (2.64±0.63) log10 IU/mL over 96 weeks in the ETV-to-switch-TMF group (P<0.001). The reduction in HBsAg levels was significantly higher in the ETV-to-switch-TMF group compared with the ETV-continuation group following 96 weeks [(0.48±0.07) log10 IU/mL vs. (0.17±0.05) log10 IU/mL, P<0.001]. The proportion of HBeAg-positive patients in the ETV-continuation group was 32.1% (25/78), 28.2% (22/78), and 24.4% (19/78) at baseline, 48 weeks, and 96 weeks, respectively. The proportion of HBeAg-positive patients in the ETV-to-switch-TMF group was 40.5% (30/74), 39.2% (29/74), and 31.1% (23/74) at baseline, 48 weeks, and 96 weeks, respectively. There was no statistically significant difference in the HBeAg seroconversion rate between the two groups of patients (χ2=0.003, P=0.954). Seventy-four patients in the ETV-continuation group (74/78, 94.9%) and seventy-one patients in the ETV-to-switch-TMF group (71/74, 95.9%) achieved undetectable HBV DNA levels at the completion of the 96-week follow-up, with no statistically significant difference in both groups of patients for achieving HBV DNA negativity (P=0.961). Compared with baseline, serum creatinine levels showed an upward trend in the ETV-continuation and ETV-to-switch-TMF groups after 96 weeks of treatment; however, the differences were not statistically significant (P>0.05). In addition, there were no statistically significant differences in triglyceride or total cholesterol levels between the two groups of patients following 96 weeks of treatment (P>0.05). Conclusion: HBsAg levels in patients with chronic hepatitis B were significantly reduced after switching from ETV to TMF therapy.