Quantification of serum hepatitis B core antibody to predict off-entecavir relapse in patients with chronic hepatitis B.

Background/purpose: The predictors of off-therapy response in patients treated with neucleos(t)ide analogue (NA) have not been elucidated. It remained unexplored whether serum level of hepatitis B core antibody (anti-HBc) at the end of NA therapy was associated with relapse risks.

Methods: This prospective study monitored 82 chronic hepatitis B (CHB) patients after discontinuing entecavir. All patients had been treated for 3 years or longer and serologically negative for viral DNA and HBeAg at treatment cessation. Patients were monitored for virological relapse (viral DNA > 2000 IU/mL), and clinical relapse (serum alanine aminotransferase > 80 U/L plus virological relapse). The association between anti-HBc levels and the risk of relapse was assessed by the Cox analysis.

Results: Clinical and virological relapses occurred in 29 and 60 participants, respectively, with the cumulative incidences of 23.7% (95% CI, 15.8-34.6%) and 62.0% (95% CI, 51.5-72.5%) at 1 year, and 36.2% (95% CI, 26.2-48.4%) and 78.8% (95% CI, 68.2-87.8%) at 2 years, respectively. There was a trend for an inverse association between anti-HBc and clinical relapse (crude hazard ratio [HR], 0.50; 95% CI, 0.24-1.05). All 3 patients with the level <100 IU/mL had a rapid clinical relapse (P = 0.002). This trend remained after adjustment for HBsAg and age (adjusted HR 0.50, 95% CI, 0.24-1.03). On the other hand, anti-HBc quantity was unrelated to virological relapse (crude HR, 0.97; 95% CI, 0.58-1.62; adjusted HR, 0.97; 95% CI, 0.58-1.60).

Conclusion: This pilot study suggests a trend for an inverse association between anti-HBc levels and clinical relapse in CHB patients off entecavir.