title: Rationale and design of the REPEAT study: a phase III, randomized, clinical trial of peginterferon alfa-2a (40 kDa) plus ribavirin in non-responders to peginterferon alfa-2b (12 kDa) plus ribavirin.
abstract: OBJECTIVE
  The REtreatment with PEgasys in pATients not responding to prior peginterferon alfa-2b (12 kDa)/ribavirin combination therapy (REPEAT) study is a phase III, randomized, parallel group, multinational clinical trial. The main objective is to compare the efficacy and safety of 48 and 72 weeks of treatment with peginterferon alfa-2a (40 kDa) (PEGASYS) plus ribavirin (COPEGUS) in patients who did not respond to previous peginterferon alfa-2b (12 kDa) plus ribavirin therapy.
  
  
  METHODS
  Patients will be randomized to one of four treatment groups: two groups will receive peginterferon alfa-2a (40 kDa) at the standard dose of 180 mug once weekly for 48 or 72 weeks. The other two groups will receive a 12-week high-dose induction regimen with peginterferon alfa-2a (40 kDa) 360 mug once-weekly followed by 60 or 36 weeks of peginterferon alfa-2a (40 kDa) 180 mug once weekly. All patients will receive the standard dose of ribavirin (1000 or 1200 mg/day) throughout treatment. The primary efficacy variable is the rate of sustained virological response, defined as non-detectable hepatitis C virus (HCV) RNA (<50 IU/ml) 24 weeks after the end of treatment. Secondary variables include the percentage of patients with non-detectable HCV RNA at the end of treatment, the percentage of patients with at least a 2-log10 decrease in serum HCV RNA at weeks 12 and 24 of treatment, and the percentage of patients with non-detectable HCV RNA at treatment weeks 12, 24 and 48. Safety data will be recorded and analysed throughout the entire course of the study with the assistance of a Safety Review Board.
authors.affiliation: Rush University Medical Center, Chicago, Illinois 60612, USA. Donald_M_Jensen@rush.edu
authors.forename: Donald M
authors.initials: DM
authors.lastname: Jensen
authors.forename: Patrick
authors.initials: P
authors.lastname: Marcellin
mesh_terms: D000328:Adult; D000368:Aged; D000998:Antiviral Agents / Q000009:adverse effects / Q000627:therapeutic use*; D004359:Drug Therapy, Combination; D005260:Female; D016174:Hepacivirus / Q000302:isolation & purification; D019698:Hepatitis C, Chronic / Q000188:drug therapy* / Q000821:virology; D006801:Humans; D000077190:Interferon alpha-2; D016898:Interferon-alpha / Q000009:adverse effects / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D011092:Polyethylene Glycols / Q000009:adverse effects / Q000627:therapeutic use*; D012367:RNA, Viral / Q000097:blood; D011994:Recombinant Proteins; D012107:Research Design; D012254:Ribavirin / Q000009:adverse effects / Q000627:therapeutic use*; D018401:Sample Size; D017211:Treatment Failure; D016896:Treatment Outcome
chemical_list: D000998:Antiviral Agents; D000077190:Interferon alpha-2; D016898:Interferon-alpha; D012367:RNA, Viral; D011994:Recombinant Proteins; D011092:Polyethylene Glycols; D012254:Ribavirin; C417083:peginterferon alfa-2b; C100416:peginterferon alfa-2a