title: Sustained virological response and its treatment predictors in hepatitis C virus genotype 4 compared to genotypes 1, 2, and 3: a meta-analysis.
abstract: BACKGROUND
  Pegylated interferon and ribavirin (PEG-IFN+RBV) may be more cost-effective than direct-acting antivirals in resource-limited settings. Current literature suggests sustained virological response (SVR) in hepatitis C virus genotype 4 (HCV-4) is similar to genotype 1 (HCV-1), but worse than 2 and 3 (HCV-2/3). However, few studies have compared treatment response between these groups and these have been limited by small sample sizes with heterogeneous designs. We performed a meta-analysis of SVR predictors in HCV-4 versus HCV-1, 2, and 3 patients treated with PEG-IFN+RBV.
  
  
  METHODS
  In November 2013, we searched for 'genotype 4' in MEDLINE/EMBASE databases and scientific conferences. We included original articles with ≥25 treatment-naïve HCV-4 and comparisons to HCV-1, 2, and/or 3 patients treated with PEG-IFN+RBV. Random effects modelling was used with heterogeneity defined by Cochrane Q-test (p value<0.10) and I(2) statistic (>50%).
  
  
  RESULTS
  Five studies with 20 014 patients (899 HCV-4; 12 033 HCV-1; and 7082 HCV-2/3 patients) were included. SVR was 53% (CI 43% to 62%) for HCV-4, 44% (CI 40% to 47%) for HCV-1; and 73% (CI 58% to 84%) for HCV-2/3. SVR with EVR (early virological response) was 75% (CI 61% to 86%) in HCV-4; 64% (CI 46% to 79%) in HCV-1; and 85% (CI 71% to 93%) in HCV-2/3. SVR without EVR was 10% (CI 6% to 17%) for HCV-4; 13% (CI 12% to 15%) for HCV-1; and 23% (CI 16% to 33%) for HCV-2/3.
  
  
  CONCLUSIONS
  SVR rates are similar in HCV-4 (∼50%) and HCV-1 (∼40%). Lack of EVR is a good stopping rule for HCV-4 and HCV-1 since only 10% subsequently achieve SVR. In HCV-4 patients with EVR, three-quarters can expect to achieve SVR with PEG-IFN+RBV.
authors.affiliation: School of Medicine, University of California , San Diego, California , USA.
authors.forename: Brittany E
authors.initials: BE
authors.lastname: Yee
authors.affiliation: School of Medicine, University of California , San Diego, California , USA.
authors.forename: Nghia H
authors.initials: NH
authors.lastname: Nguyen
authors.affiliation: School of Medicine, University of California , San Diego, California , USA.
authors.forename: Bing
authors.initials: B
authors.lastname: Zhang
authors.affiliation: Department of Internal Medicine , Stanford University Medical Centre , Palo Alto, California , USA.
authors.forename: Derek
authors.initials: D
authors.lastname: Lin
authors.affiliation: Department of Internal Medicine , Rush University Medical Centre , Chicago, Illinois , USA.
authors.forename: Philip
authors.initials: P
authors.lastname: Vutien
authors.affiliation: Department of Medicine , North Shore-Long Island Jewish Health System , Manhasset, New York , USA.
authors.forename: Carrie R
authors.initials: CR
authors.lastname: Wong
authors.affiliation: Division of Gastroenterology and Hepatology , Stanford University Medical Centre , Palo Alto, California , USA.
authors.forename: Glen A
authors.initials: GA
authors.lastname: Lutchman
authors.affiliation: Division of Gastroenterology and Hepatology , Stanford University Medical Centre , Palo Alto, California , USA.
authors.forename: Mindie H
authors.initials: MH
authors.lastname: Nguyen
keywords: GENOTYPE; HCV; HEPATITIS C