Efficacy and Safety of Switching from Entecavir to Tenofovir Alafenamide for Chronic Hepatitis B Patients with Low-Level Viremia.

OBJECTIVE: Clinical data on the efficacy and safety of tenofovir alafenamide fumarate (TAF) in chronic hepatitis B (CHB) patients with suboptimal response to entecavir (ETV) are limited. This study was designed to investigate the efficacy and safety of switching to TAF in CHB patients with low-level viremia (LLV). METHODS: CHB patients with LLV who received ETV treatment for more than 52 weeks were divided into TAF group (n = 104) and ETV group (n = 395). Propensity score matching (PSM) was performed to adjust for baseline differences in age between the two groups. The outcomes included complete virological response (CVR) at weeks 12 and 24, normalization rates of aminotransferase (ALT) and aspartate aminotransferase (AST), and renal function and blood lipid levels. RESULTS: Compared with the ETV group, the TAF group had significantly higher rates of CVR at week 12 and week 24 in both the raw cohort and the PSM cohort (all P < 0.05). In the PSM cohort, the superiority of TAF over ETV in achieving CVR remained statistically significant at both time points (all P < 0.05). ALT and AST normalization rates were also significantly greater in the TAF group than in the ETV group at week 24 (all P < 0.05). No significant differences in creatinine (Cr) levels or estimated glomerular filtration rate (eGFR) were observed between week 24 and baseline in the raw cohort. No significant changes in blood lipid levels were detected in the TAF group at week 24 (all P > 0.05). CONCLUSION: Switching to TAF may be beneficial for patients with LLV after prolonged ETV therapy, as it is associated with a significantly higher rate of CVR. No lipid metabolism-related disorders were observed following the switch to TAF.