Combining end-of-treatment HBsAg and baseline hepatitis B core-related antigen reduce HBV relapse rate after tenofovir cessation

Background/purpose: The study investigated the role of hepatitis B core-related antigen (HBcrAg) in hepatitis B virus (HBV) relapse after stopping tenofovir disoproxil fumarate (TDF) in HBeAg-negative patients. Methods: A total of 185 HBeAg-negative patients without cirrhosis who had stopped TDF treatment for at least 6 months were recruited. All patients fulfilled the stopping criteria proposed by the Asian Pacific Association for the Study of the Liver 2012. Results: The 3-year cumulative incidences of virological relapse, clinical relapse, and hepatitis B surface antigen (HBsAg) loss were 72, 60.1 and 14.5%, respectively. End-of-treatment (EOT) HBsAg level was an independent predictor of virological relapse (hazard ratio (HR): 2.263; 95% confidence interval (CI): 1.779–2.887), clinical relapse (HR 1.773; 95% CI 1.367–2.298), and HBsAg loss (HR 0.179; 95% CI 0.096–0.335). Among patients who had HBsAg < 100 and ≥ 100 IU/mL, the 3-year virological relapse rates were 37.4% and 85.3% (p < 0.001), clinical relapse rates were 30.3 and 71.7% (p < 0.001), and HBsAg loss rates were 40.6 and 2.6% (p < 0.001), respectively. Among the 53 patients with EOT HBsAg level < 100 IU/mL, the 3-year virological relapse rates in patients with baseline HBcrAg levels < 4.7 and ≥ 4.7 log₁₀ U/mL were 20.3 and 60.4% (p = 0.003), and the clinical relapse rates were 10.3 and 59.5% (p < 0.001) respectively. Additionally, the 3-year HBsAg loss rates in patients with baseline HBcrAg ≤ 3 and > 3 log₁₀ U/mL were 42.9 and 7.9% (p < 0.001). Conclusions: The combination of EOT HBsAg and baseline HBcrAg levels could further reduce the risk of HBV relapse after stopping TDF therapy in HBeAg-negative patients.