title: Pretreatment with pegylated interferon prevents emergence of lamivudine mutants in lamivudine-naive patients: a pilot study.
abstract: BACKGROUND
  In patients with advanced fibrosis, primary end points of long-term or possibly indefinite antiviral therapy are sustained inhibition of viral replication and avoidance of emergence of resistance. In lamivudine-treated patients, the strongest predictor of emergence of YMDD mutations is baseline hepatitis B virus (HBV) DNA viral load. We aimed to verify whether abatement of viraemia by a short course of pegylated interferon (PEG-IFN-alpha2a) treatment before lamivudine treatment could prevent the emergence of lamivudine-associated mutations during long-term therapy.
  
  
  METHODS
  A total of 14 patients with hepatitis B e antigen (HBeAg)-negative infection (3 lamivudine-experienced and 11 lamivudine-naive), with moderate/high viraemia (>10(6) copies/ml) and with Ishak stage 4-6 at liver biopsy were sequentially treated with 180 microg PEG-IFN-alpha2a for a period long enough to reach HBV DNA levels < or =10(3) copies/ml or have a decrease of 3 log(10) copies/ml from baseline. Lamivudine was then added to PEG-IFN-alpha2a treatment for 1 month and finally continued as monotherapy for 2 years or until viral breakthrough.
  
  
  RESULTS
  Baseline HBV DNA (mean +/-se 2.3 x 10(7) +/-7.2 x 10(7) copies/ml) decreased with PEG-IFN-alpha2a treatment to target value in mean +/-se 3.7 +/-1.3 months. None of the 11 lamivudine-naive patients developed genotypic resistance and were still HBV-DNA-negative after a mean +/-se observation period of 23 +/-2 months, whereas the three lamivudine-experienced patients developed YMDD mutations after 6, 9 and 12 months of lamivudine monotherapy (P=0.003, Fisher's exact test).
  
  
  CONCLUSIONS
  In lamivudine-naive patients, abatement of HBV DNA<10(3) copies/ml by pretreatment with PEG-IFN-alpha2a completely prevents the emergence of YMDD mutants after 24 months of lamivudine monotherapy. This sequential schedule can optimize the use of a well tolerated, effective and inexpensive drug, such as lamivudine, in highly viraemic HBV patients.
authors.affiliation: Gastroenterology Unit, Azienda Ospedaliero-Universitaria, University of Modena and Reggio Emilia, Modena, Italy. erica.villa@unimore.it
authors.forename: Erica
authors.initials: E
authors.lastname: Villa
authors.forename: Barbara
authors.initials: B
authors.lastname: Lei
authors.forename: Gloria
authors.initials: G
authors.lastname: Taliani
authors.forename: Amalia
authors.initials: A
authors.lastname: Graziosi
authors.forename: Rosina
authors.initials: R
authors.lastname: Critelli
authors.forename: Monica
authors.initials: M
authors.lastname: Luongo
authors.forename: William
authors.initials: W
authors.lastname: Gennari
authors.forename: Marcello
authors.initials: M
authors.lastname: Bianchini
authors.forename: Ilva
authors.initials: I
authors.lastname: Ferretti
mesh_terms: D000998:Antiviral Agents / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D004279:DNA, Viral / Q000097:blood; D004334:Drug Administration Schedule; D024882:Drug Resistance, Viral / Q000187:drug effects / Q000235:genetics; D005260:Female; D005838:Genotype; D006515:Hepatitis B virus / Q000187:drug effects* / Q000235:genetics / Q000502:physiology; D019694:Hepatitis B, Chronic / Q000188:drug therapy* / Q000821:virology; D006801:Humans; D000077190:Interferon alpha-2; D016898:Interferon-alpha / Q000008:administration & dosage / Q000627:therapeutic use; D019259:Lamivudine / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009154:Mutation; D010865:Pilot Projects; D011092:Polyethylene Glycols / Q000008:administration & dosage / Q000627:therapeutic use; D011994:Recombinant Proteins; D016896:Treatment Outcome
chemical_list: D000998:Antiviral Agents; D004279:DNA, Viral; D000077190:Interferon alpha-2; D016898:Interferon-alpha; D011994:Recombinant Proteins; D019259:Lamivudine; D011092:Polyethylene Glycols; C100416:peginterferon alfa-2a