Combined viral quasispecies diversity and hepatitis B core-related antigen predict off-nucleos(t)ide analog durability in HBeAg-negative patients.

Abstract

Viral quasispecies dynamics between pre- and post-nucleos(t)ide analog (NA) therapy remains unclear. This study aimed to investigate the HBV quasispecies evolution and its relationship with durability of off-therapy responses in HBeAg-negative chronic hepatitis B (CHB) patients who stopped NA therapy. Fifty-four HBeAg-negative CHB patients who stopped NAs, including 19 virological controllers (VC) who maintained serum HBV DNA < 2000IU/mL beyond 1-year off-therapy, and 35 virological relapsers (VR) experiencing virological relapse within 1-year off-therapy were recruited. Viral quasispecies was analyzed by deep sequencing. Hepatitis B core-related antigen (HBcrAg) and HBsAg were also measured. VC had significantly higher baseline viral quasispecies diversity of the precore/core gene, measured by nucleotide diversity, than VR. Low baseline viral nucleotide diversity (< 0.01) and high HBcrAg (≧ 2.0 KU/mL), but not HBsAg, at end of treatment (EOT) were significantly associated with higher risk of 1-year virological relapse (hazard ratio [HR] 6.09 and 3.31, respectively). Combination of low baseline viral nucleotide diversity and high HBcrAg at EOT could identify patients at high risk (HR 15.82). Further analysis of the evolution of HBV whole genome showed that HBV nucleotide diversity negatively correlated with serum HBV DNA levels. Notably, the viral quasispecies diversity between pre- and post-NA treatment remained relatively unchanged. Higher baseline HBV quasispecies diversity associates with more durable off-therapy viral suppression in HBeAg-negative CHB patients. Combination of baseline viral nucleotide diversity and HBcrAg at EOT can identify patients at high risk for virological relapse after stopping NAs.