title: Peginterferon alfa-2a relapse rates depend on weight-based ribavirin dosage in HCV-infected patients with genotype 1: results of a retrospective evaluation.
abstract: OBJECTIVE
  The cumulative dosage of ribavirin per kilogram of body-weight prevents relapse and thus is a significant predictor of sustained virological response (SVR). Comparison of peginterferon (peg-IFN) alfa-2b/ribavirin and peg-IFN alfa-2a/ribavirin shows that the rates of SVR are similar, but the rates of relapse are significantly lower under the peg-IFN alfa-2b regimen. Depending on the weight-based ribavirin dose, patients with >105 kg reach a maximum of 13.2 mg/kg body-weight ribavirin in the peg-IFN alfa-2b regimen as opposed to only 11.3 mg/kg in the peg-IFN alfa-2a regimen. The aim of these investigations was to determine relapse rates in a retrospective analysis of 98 patients chronically infected with hepatitis C virus (HCV) genotype (GT) 1 in relation to the weight-based ribavirin dose.
  
  
  METHODS
  All patients completed treatment with peg-IFN alfa-2a/ribavirin (1000 mg/d or 1200 mg/d for patients weighing <75 kg or > or =75 kg) for 48 weeks. Classification of a low ribavirin dose with <13.2 mg/kg body-weight was used. Patients with a ribavirin dose > or =13.2 mg/kg were compared with those with a dose <13.2 mg/kg.
  
  
  RESULTS
  Patients with a ribavirin dose > or = 13.2 mg/kg (n=84) showed a relapse rate of 19.0% in contrast to 71.4% in patients with a ribavirin dose of <13.2 mg/kg (n=14) (p=0.0013). The SVR rate was significantly higher in the > or =13.2 mg/kg ribavirin dosed group (59.5% versus 28.6%).
  
  
  CONCLUSIONS
  Weight-adapted ribavirin dosing in combination with peg-IFN alfa-2a to avoid giving low doses of ribavirin should be evaluated. This will minimize relapse, especially in HCV GT 1 patients.
authors.affiliation: Medical Department 1, Hepatology and Gastroenterology, Friedrich-Alexander University of Erlangen, Germany. Steffen.Zopf@uk-erlangen.de
authors.forename: Steffen
authors.initials: S
authors.lastname: Zopf
authors.forename: Christoph
authors.initials: C
authors.lastname: Herold
authors.forename: Eckhart G
authors.initials: EG
authors.lastname: Hahn
authors.forename: Marion
authors.initials: M
authors.lastname: Ganslmayer
mesh_terms: D000328:Adult; D000998:Antiviral Agents / Q000008:administration & dosage*; D001835:Body Weight; D015331:Cohort Studies; D004305:Dose-Response Relationship, Drug; D004359:Drug Therapy, Combination; D005260:Female; D005838:Genotype; D016174:Hepacivirus / Q000235:genetics; D006526:Hepatitis C / Q000188:drug therapy* / Q000821:virology; D006801:Humans; D000077190:Interferon alpha-2; D016898:Interferon-alpha / Q000008:administration & dosage*; D008297:Male; D008875:Middle Aged; D011092:Polyethylene Glycols / Q000008:administration & dosage*; D011994:Recombinant Proteins; D012008:Recurrence; D012189:Retrospective Studies; D012254:Ribavirin / Q000008:administration & dosage*
chemical_list: D000998:Antiviral Agents; D000077190:Interferon alpha-2; D016898:Interferon-alpha; D011994:Recombinant Proteins; D011092:Polyethylene Glycols; D012254:Ribavirin; C417083:peginterferon alfa-2b; C100416:peginterferon alfa-2a