Comparison Between Horse And Rabbit Antithymocyte Globulin As The First-line Treatment For Patients With Aplastic Anemia: Systematic Review And Meta-analysis

Introduction:The combination of antithymocyte globulin(ATG) and cyclosporine A(Cs A) is a standard regimen in immunosuppressive therapy(IST) for patients with aplastic anemia who are ineligible for allogeneic haematopoietic stem cell transplantation(HSCT).A number of studies have been reported comparing horse ATG and rabbit ATG combination with Cs A in aplastic anemia patients.However,there is still debate about the efficacy of horse ATG and Cs A compared with rabbit ATG and Cs A.The aim of our systematic review and meta-analysis was to assess the efficacy of horse ATG and rabbit ATG plus Cs A in patients with aplastic anemia.Method:A systematic search was performed in the bibliographic databases MEDLINE, EMBASE, and the Cochrane Library.Data were evaluated and extracted by two reviewers independently with designed extraction form. Odds ratio(OR) with 95% confidence intervals(CIs) were estimated for each trial and pooled. The Rev Man 5.2 software was used for data analyses.Results:Our search yielded 11 trials(1,441 patients enrolled),including 1 randomized controlled trial and 10 non-randomized controlled trials.Patients with horse ATG at six months showed a better hematologic response than those with rabbit ATG(OR:1.82, 95%CI:1.20–2.76).The overall mortality of horse ATG was significantly higher compaired with rabbit ATG(OR:0.58,95%CI:0.39–0.88). Meanwhile,horse ATG exhibited improved survival rates,two-years-survival rates(OR=3.87,95%CI:2.25-6.65) and three-years-survival rates(OR=6.72, 95% CI:3.14-14.36).Conclusion:The combination of horse ATG and Cs A is obviously reduced all-cause mortality and improved overall survival compared with rabbit ATG.