title: Long-term efficacy of interferon alpha therapy on hepatitis B viral replication in patients with chronic hepatitis B: a meta-analysis.
abstract: OBJECTIVE
  Interferon (IFN) alpha has been used in the treatment of chronic hepatitis B for decades. Beneficial effects including hepatitis B e antigen (HBeAg)/HBV DNA seroclearance have been documented. However, it remains unclear whether interferon has long-term efficacy on inhibiting hepatitis B viral replication. So we conducted a meta-analysis of available literature to assess the evidence obtained on the efficacy of IFN treatment in chronic HBV infection.
  
  
  METHODS
  Seven clinical controlled trials, including 1550 patients and comparing IFN to no treatment, were selected. Data on the incidence of HBV DNA seroclearance, HBeAg seroclearance, and HBsAg seroclearance in IFN treated and untreated patients were extracted from each study. The evaluation of effectiveness was performed with an intention-to-treat (ITT) method. We used the relative risk (RR) and 95% confidence interval (CI) of the main outcomes as the measure of efficacy. Meta-analysis was performed using fixed-effect or random-effect methods, depending on absence or presence of significant heterogeneity. Analyses were performed with STATA version 9.0 and Review Manager Version 4.2.
  
  
  RESULTS
  Four studies including the data of HBeAg seroclearance with significant heterogeneity were analyzed by random-effect method; six studies including the data of HBsAg seroclearance without significant heterogeneity were analyzed by fixed-effect method. A different incidence of HBeAg seroclearance and HBsAg seroclearance was observed between treated and untreated patients. The RR of HBeAg seroclearance and HBsAg seroclearance was 0.66 (95% CI: 0.44, 0.99) and 0.28 (95% CI: 0.17, 0.46), respectively.
  
  
  CONCLUSIONS
  In conclusion, the results of this meta-analysis indicate that IFN increases the incidence of HBeAg seroclearance and HBsAg seroclearance after long-term follow-up of three to seven years.
authors.affiliation: Liver Disease Department, The Second Affiliated Hospital of South East University, 1-1 Zhongfu Road, Nanjing 210003, Jiangsu Province, China. henanyyf@hotmail.com
authors.forename: Yong-Feng
authors.initials: YF
authors.lastname: Yang
authors.forename: Wei
authors.initials: W
authors.lastname: Zhao
authors.forename: Hai-Ming
authors.initials: HM
authors.lastname: Xia
authors.forename: Yan-Dan
authors.initials: YD
authors.lastname: Zhong
authors.forename: Ping
authors.initials: P
authors.lastname: Huang
authors.forename: Jian
authors.initials: J
authors.lastname: Wen
mesh_terms: D000998:Antiviral Agents / Q000627:therapeutic use*; D018849:Controlled Clinical Trials as Topic; D004279:DNA, Viral / Q000097:blood; D005260:Female; D005500:Follow-Up Studies; D006514:Hepatitis B Surface Antigens / Q000097:blood; D006513:Hepatitis B e Antigens / Q000097:blood; D019694:Hepatitis B, Chronic / Q000188:drug therapy*; D006801:Humans; D016898:Interferon-alpha / Q000627:therapeutic use*; D008297:Male; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000998:Antiviral Agents; D004279:DNA, Viral; D006514:Hepatitis B Surface Antigens; D006513:Hepatitis B e Antigens; D016898:Interferon-alpha