title: Virologic response at 12 months of treatment predicts sustained antiviral efficacy in patients with adefovir-treated Lamivudine-resistant chronic hepatitis B.
abstract: OBJECTIVE
  The aim of our study was to define the potential role of virologic response at 12 months of treatment (VR12) in predicting subsequent virologic and clinical outcomes in adefovir (ADV)-treated lamivudine-resistant chronic hepatitis B.
  
  
  METHODS
  Two hundred and four patients with lamivudine-resistant chronic hepatitis B virus (HBV) treated with ADV monotherapy were included. Serum HBV DNA was quantified by real-time polymerase chain reactions. VR12 was defined as a HBV DNA level of less than 4 log(10) copies/mL after 12 months of ADV treatment.
  
  
  RESULTS
  VR12 was observed in 110 of the 204 patients (54%). The mean HBV DNA reductions from baseline after 12 months of ADV treatment were 3.8 and 1.9 log(10) copies/mL in patients with and without VR12, respectively (p<0.001). The hepatitis B "e" antigen (HBeAg) seroconversion rates in patients with and without VR12 were 32% and 14% at 12 months treatment, respectively (p=0.018), and 40% and 27% at 24 months of treatment (p=0.032). The genotypic mutation rates to ADV in patients with and without VR12 were 0% and 6% at 12 months of treatment, respectively (p=0.033), and 21% and 42% at 24 months (p=0.012). The rates of viral breakthrough in patients with and without VR12 were 0% and 7% at 12 months of treatment, respectively (p=0.072), and 9% and 25% at 24 months (p=0.006).
  
  
  CONCLUSIONS
  Patients without VR12 may need to switch to or add on other potent antiviral drugs in their medical regimens.
authors.affiliation: Department of Internal Medicine, Korea University Guro Hospital, Korea University College of Medicine, Seoul, Korea.
authors.forename: Young Kul
authors.initials: YK
authors.lastname: Jung
authors.forename: Jong Eun
authors.initials: JE
authors.lastname: Yeon
authors.forename: Woo Sik
authors.initials: WS
authors.lastname: Han
authors.forename: Ji Hoon
authors.initials: JH
authors.lastname: Kim
authors.forename: Jeong Han
authors.initials: JH
authors.lastname: Kim
authors.forename: Jong-Jae
authors.initials: JJ
authors.lastname: Park
authors.forename: Jae Seon
authors.initials: JS
authors.lastname: Kim
authors.forename: Young-Tae
authors.initials: YT
authors.lastname: Bak
authors.forename: Wangdon
authors.initials: W
authors.lastname: Yoo
authors.forename: Sun Pyo
authors.initials: SP
authors.lastname: Hong
authors.forename: Soo-Ok
authors.initials: SO
authors.lastname: Kim
authors.forename: So Young
authors.initials: SY
authors.lastname: Kwon
authors.forename: Kwan Soo
authors.initials: KS
authors.lastname: Byun
authors.forename: Chang Hong
authors.initials: CH
authors.lastname: Lee