Comparison of the efficacy of rabbit and horse antithymocyte globulin for the treatment of severe aplastic anemia in children

摘要

Immunosuppressive therapy (IST) with horse antithymocyte globulin (h-ATG) and cyclosporine (CSA) is an effective therapy for aplastic anemia (AA), resulting in a response rate of 60%-70% and an excellent survival for responders. However, lymphoglobulin (h-ATG; Genzyme) was withdrawn from the market in 2007. Because of the unavailability of h-ATG in most countries, the evaluation of rabbit ATG (r-ATG) as first-line therapy was stimulated. Marsh et al recently showed a low response to IST at 6 months (37%) in 35 patients who were given r-ATG (thymoglobulin; Genzyme).1 The overall survival at 2 years was significantly lower (68%) compared with age- and disease-matched patients given h-ATG (n = 105, 86% P = .009). Furthermore, in a randomized controlled trial, Scheinberg et al showed an inferior response (37% vs 68% at 6 months, P < .001) and a decreased survival (76% vs 96%, 2 years, P = .04) after r-ATG (thymoglobulin) compared with h-ATG (ATGAM; Pfizer).2 In none of the published series r-ATG was found to be superior to h-ATG.3,4 However, these series did not focus on outcome of children, so we compared both ATGs in children with AA.