Clinical characteristics of patients with chronic hepatitis B who developed genotypic resistance to entecavir: Real-life experience

Abstract

Background/Aims Clinical characteristics of patients with chronic hepatitis B (CHB) who developed genotypic resistance to entecavir (ETV) were compared to those without resistance. Methods Two hundred fifty eight CHB patients who underwent ETV treatment in our institution from July 2007 to May 2013 were included. Results Eight (3.1%) patients developed genotypic resistance to ETV during the follow-up period. The patterns of genotypic resistance to ETV were as follows: L180M + M204V + S202G (n=3); M204I + V173M (n=1); I169V + V173M (n=1); L180M + M204V + V173L (n=1); L180M + M204V + V173L + M250V (n=1); M204I + V214A + P237H (n=1). The cumulative occurrence rates of genotypic resistance to ETV were not significantly different between CHB patients with prior nucleos(t)tide analogues (NA) exposure (NA experienced, n=56) and NA naïve patients (n=202, P=0.823 by log rank comparison). Older age, higher baseline log10hepatitis B virus-deoxynucleic acid (log10HBV-DNA), higher log10HBV-DNA at 3, 6, 12 and 24 months after baseline, and complete virologic response (CVR, undetectable serum HBV-DNA by polymerase chain reaction 6 months after ETV treatment) were significant contributors to the development of genotypic resistance to ETV. Multivariate analyses showed higher log10HBV-DNA 6 months after baseline and absence of CVR were independent and significant contributors to the development of ETV resistance. Conclusions Clinical characteristics of patients who developed ETV resistance were higher log10HBV-DNA 6 months after baseline and absence of CVR during the ETV treatment.

Keywords

• Entecavir
• Genotypic resistance
• HBV-DNA
• HBeAg
• Complete virologic response