A real-time quantitative polymerase chain reaction method for hepatitis B virus in patients with chronic hepatitis B treated with lamivudine

Am J Gastroenterol. 2003 Sep;98(9):2048-51. doi: 10.1111/j.1572-0241.2003.07643.x.


Objectives: During treatment of chronic hepatitis B with lamivudine, changes in the level of hepatitis B virus (HBV) DNA were investigated using a real-time polymerase chain reaction (PCR) method with a detection limit of 1.7 log copies/ml (50 copies/ml) to clarify its clinical significance, particularly the association between HBV DNA levels and the emergence of tyrosine-methionine-aspartate-aspartate (YMDD) mutants.

Methods: Twenty-four patients who had received lamivudine therapy for >1 yr were studied. HBV DNA levels were determined using transcription-mediated amplification for sera with >3.7 log genome equivalents/ml, the Roche Monitor kit for sera with >/=2.6 log copies/ml, and real-time PCR for sera with < 2.6 log copies/ml (the detection limit was 1.7 log copies/ml). Patients were classified into three groups according to the minimal HBV DNA level attained during lamivudine therapy: the <1.7 log copies/ml group (eight patients), the 1.7-2.5 log copies/ml group (five patients), and the >/=2.6 log copies/ml group (11 patients).

Results: Pretreatment HBV DNA levels were significantly lower in the <1.7 copies/ml group than in the other two groups (p < 0.05). Neither the emergence of YMDD mutants nor a virological breakthrough of serum HBV DNA was observed in any of the eight patients in the <1.7 copies/ml group. In contrast, in the 1.7-2.5 copies/ml and >/=2.6 copies/ml groups, virological breakthroughs resulting from the emergence of YMDD mutants were observed in two of five patients and in all 11 patients, respectively (p < 0.001). Virological breakthroughs were observed at a mean of 49.6 +/- 18.4 wk in 11 the patients in the >/=2.6 copies/ml group and at wk 107 and 115 in two patients in the 1.7-2.5 copies/ml group.

Conclusions: The real-time PCR method is useful for predicting the emergence of YMDD mutants and the estimated time of their emergence.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Base Sequence
  • Cohort Studies
  • DNA Mutational Analysis
  • DNA, Viral / analysis*
  • Dose-Response Relationship, Drug
  • Drug Administration Schedule
  • Female
  • Genes, Viral
  • Hepatitis B virus / drug effects
  • Hepatitis B virus / genetics*
  • Hepatitis B, Chronic / drug therapy*
  • Hepatitis B, Chronic / genetics
  • Humans
  • Lamivudine / administration & dosage*
  • Male
  • Middle Aged
  • Molecular Sequence Data
  • Mutation
  • Probability
  • Prognosis
  • Prospective Studies
  • Reverse Transcriptase Polymerase Chain Reaction*
  • Sensitivity and Specificity
  • Statistics, Nonparametric


  • DNA, Viral
  • Lamivudine