title: Peginterferon alfa-2a is superior to peginterferon alfa-2b in the treatment of naïve patients with hepatitis C virus infection: meta-analysis of randomized controlled trials.
abstract: BACKGROUND
  Pegylated interferon (PEGIFN) and ribavirin combination is the standard of care for the treatment of chronic hepatitis C virus (HCV) infection. Studies comparing the efficacy and safety of PEGIFN alfa-2a and PEGIFN alfa-2b in treatment-naïve HCV-infected patients have shown conflicting results.
  
  
  OBJECTIVE
  We performed a systematic review and meta-analysis of studies comparing the efficacy and safety of PEGIFN alfa-2a and PEGIFN alfa-2b in HCV-infected patients naïve to treatment.
  
  
  METHODS
  Nine studies (five abstracts) with 3,546 patients (1,771 treated with PEGIFN alfa-2a) comparing PEGIFN alfa-2a and PEGIFN alfa-2b in treatment-naïve HCV patients were analyzed. Efficacy outcomes were sustained virologic response (SVR) and treatment discontinuation rates due to serious adverse effects (SAE).
  
  
  RESULTS
  Pooled data on outcomes (reported as odds ratios [ORs] with 95% confidence intervals [CIs]: [OR (95% CI)]) showed higher SVR in patients treated with PEGIFN alfa-2a as compared to treatment with PEGIFN alfa-2b [1.36 (1.07-1.73); P=0.01]. Subgroup analysis of good quality studies on SVR in genotypes 2 and 3 also favored PEGIFN alfa-2a over PEGIFN alfa-2b (1.91 [1.09-3.37]; P=0.02). SVR results obtained with the two types of IFN showed no impact of viral load and the presence or absence of cirrhosis. Treatment discontinuation rates due to SAE, reported in six studies (two abstracts) on 3,211 patients (1,604 treated with PEGIFN alfa-2a), were similar in the two types of PEGIFN [0.66 (0.37-1.16); P=0.15].
  
  
  CONCLUSIONS
  PEGIFN alfa-2a has superior efficacy with higher SVR as compared to PEGIFN alfa-2b in treatment-naïve HCV-infected patients. The safety profile of the two types of PEGIFN was similar.
authors.affiliation: Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX 77555-0764, USA. aksingal@utmb.edu
authors.forename: Ashwani K
authors.initials: AK
authors.lastname: Singal
authors.forename: Sarat C
authors.initials: SC
authors.lastname: Jampana
authors.forename: Bhupinderjit S
authors.initials: BS
authors.lastname: Anand
mesh_terms: D000328:Adult; D000998:Antiviral Agents / Q000627:therapeutic use*; D004359:Drug Therapy, Combination; D005260:Female; D019698:Hepatitis C, Chronic / Q000188:drug therapy*; 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*; D016032:Randomized Controlled Trials as Topic; D011994:Recombinant Proteins; D012254:Ribavirin / Q000009:adverse effects / Q000627:therapeutic use; D016896:Treatment Outcome; D019562:Viral Load / Q000187:drug effects
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