First-line oral antiviral therapies showed similar efficacies in suppression of serum HBcrAg in chronic hepatitis B patients

Background Serum hepatitis B core-related antigen (HBcrAg) is a potential surrogate marker for intra-hepatic covalently-closed circular DNA in chronic hepatitis B (CHB). We aimed to study the profiles of serum HBcrAg in CHB patients treated with first-line nucleos(t)ide analogues (NA): entecavir (ETV), tenofovir disoproxil fumarate (TDF) or tenofovir alafenamide (TAF). Method Serum HBcrAg was measured in 120 treatment-naïve CHB patients receiving one of the 3 NAs (ETV: TDF: TAF = 60: 26: 34) using the Lumipulse G HBcrAg assay in a Lumipulse G1200 analyzer (Fujirebio Inc, Toyko, Japan). Serum HBcrAg levels were measured at week 0, week 48 and week 96 of NA therapy. Results Among the 120 patients, 67 (55.8%) were hepatitis B e antigen (HBeAg) positive. Both tenofovir and ETV led to significantly lower serum HBcrAg at week 48 and week 96 compared to week 0. There were no significant differences for the magnitude of median HBcrAg decline at week 96 between tenofovir and ETV in HBeAg-positive (2.28 vs. 1.65 log U/mL, p > 0.05) and HBeAg-negative (0.83 vs. 0.54 log U/mL, p > 0.05) patients. TDF and TAF produced no significant differences in the magnitude of median HBcrAg decline at week 96 (HBeAg-positive: 2.63 vs. 1.83, respectively; HBeAg-negative: 1.04 vs. 0.40, respectively; both p > 0.05). Conclusion Magnitude of reduction of HBcrAg levels after 2-year first-line treatment did not differ statistically among the current first-line NAs, although HBcrAg reduction was numerically greater in tenofovir-treated group. More long-term studies are essential to determine whether tenofovir exerts a more pronounced effect on HBcrAg.