Lamivudine-to-entecavir switching treatment in type B chronic hepatitis patients without evidence of lamivudine resistance

J Gastroenterol. 2009;44(8):864-70. doi: 10.1007/s00535-009-0076-0. Epub 2009 May 28.

Abstract

Purpose: A considerable number of chronic hepatitis B (CH-B) patients remain under continuous lamivudine treatment, although switching treatment to entecavir could be beneficial. We investigated the antiviral efficacy of switching treatment to entecavir in CH-B patients without apparent evidence of lamivudine resistance during the preceding lamivudine treatment.

Methods: Forty-four CH-B patients, who underwent lamivudine treatment for more than 6 months and showed no evidence of lamivudine resistance, switched to entecavir. Serial changes in hepatitis B virus (HBV) DNA were correlated with the patients' baseline HBV DNA at the commencement of entecavir administration. The entecavir-resistant substitution was examined by PCR-direct sequencing. The median follow-up period of entecavir treatment was 20 (10-23) months.

Results: All 31 patients with baseline HBV DNA <2.6 logcopies/ml maintained HBV DNA-negative status during entecavir treatment. Of seven patients having HBV DNA of 2.6-<4.0 logcopies/ml, all achieved undetectable HBV DNA at the end of follow-up. As for six patients having HBV DNA >or=4.0 logcopies/ml, three patients achieved undetectable HBV DNA, whereas virological breakthrough was observed in one patient at month 15. An entecavir-resistant virus having rtM204V, rtL180M and rtS202G substitutions was detected in this patient.

Conclusions: The lamivudine-to-entecavir switching treatment may be generally recommendable in CH-B patients without evidence of lamivudine resistance during the preceding lamivudine treatment. However, great care should be taken with respect to the emergence of entecavir-resistance, especially in patients who do not respond well to the preceding lamivudine treatment.

Publication types

  • Clinical Trial
  • Multicenter Study

MeSH terms

  • Adult
  • Aged
  • Antiviral Agents / therapeutic use*
  • DNA, Viral / blood
  • Drug Resistance, Viral
  • Female
  • Follow-Up Studies
  • Guanine / analogs & derivatives*
  • Guanine / therapeutic use
  • Hepatitis B virus / drug effects
  • Hepatitis B, Chronic / drug therapy*
  • Humans
  • Lamivudine / therapeutic use*
  • Male
  • Middle Aged
  • Polymerase Chain Reaction
  • Sequence Analysis, DNA

Substances

  • Antiviral Agents
  • DNA, Viral
  • Lamivudine
  • entecavir
  • Guanine