A fludarabine-based conditioning regimen for severe aplastic anemia

Graft rejection is a common problem after alternative donor transplantation for patients with refractory severe aplastic anemia (SAA). Intensification of the conditioning regimen, with the inclusion of irradiation, has often been advocated to combat this problem. With this approach engraftment rate improved, but the incidence of transplant-related complications is also inc reased, resulting in little change in the overall outcome. We investigated the use of the combination of fludarabine, cyclophosphamide and anti-thymoc yte globulin as the conditioning regimen in five multiply-transfused SAA pa tients. Three patients received an HLA one-antigen disparate related donor transplant, while two patients were given marrow from matched, unrelated do nors. The regimen was well tolerated, with only grade I toxicity encountere d. With a median follow-up of 9 months, all patients are alive with complet e donor chimerism, We conclude that fludarabine may be used in place of irr adiation to augment the conditioning regimen of cyclophosphamide and anti-t hymocyte globulin for alternative donor transplantation in children with SA A.