Reduced-intensity conditioning with busulfan and fludarabine with or without antithymocyte globulin in HLA-identical sibling transplantation -: a retrospective analysis

It is unknown whether the addition of antithymocyte globulin (ATG) to reduced-intensity conditioning with busulfan (BU) and fludarabine (FLU) is beneficial in HLA-identical sibling transplantation. Therefore, we analyzed retrospectively data on 83 patients, who received peripheral blood stem cells from HLA-identical siblings after conditioning with either 8 mg/kg BU and 150 mg/m(2) FLU (n = 45) or 8 mg/kg BU, 180 mg/m(2) FLU and 40 mg/kg ATG (n = 38). Graft-versus-host disease (GVHD) prophylaxis consisted of CSA alone (n = 32) or a combination with either MTX or MMF (n = 51). The median age was 52 years. Graft failure occurred in two patients after BU/FLU and in three after BU/FLU/ATG (P = 0.66). After conditioning with BU/FLU, platelet recovery was significantly faster (P = 0.017), and less platelet (P < 0.001) and red blood cell (P = 0.002) support was needed. Incidences of acute GVHD grades II and IV were 46 and 49%, respectively. Limited chronic GVHD occurred more often after BU/FLU compared to BU/FLU/ATG (54 vs 23%, P = 0.02). The overall survival, non-relapse and relapse mortality did not differ significantly. We conclude that in peripheral blood stem cell transplantation from HLA-identical siblings after reduced-intensity conditioning with BU and FLU, ATG has no major impact on the rate of graft rejection and acute GVHD, but it reduces the incidence of limited chronic GVHD.