Once daily busulfan cyclophosphamide is well tolerated and effective as a preparative regimen for allogeneic hematopoietic stem cell transplant

We report a retrospective review of our institutional data using once daily intravenous (IV) busulfan (Bu) and cyclophosphamide (Cy) and total body irradiation (TBI)/Cy in patients who received allogeneic hematopoietic stem cell transplant (HCT) from January 2000 to December 2006. Bu 3.2 mg/kg IV once daily × 4 days followed by Cy 60 mg/kg IV daily × 2 days was given to 42 patients. Cy 60 mg/kg IV daily for 2 days and fractionated TBI 1200 cGy delivered over 3 days was given to 60 patients. Veno-occlusive disease developed in two patients in the once daily BuCy group and no patients in the TBI/Cy group. The once daily BuCy group had significantly less transplant-related mortality (TRM) than the TBI/Cy group at 100 days (p = 0.047) and better overall survival at 1 year (p = 0.01). This review demonstrates once daily IV BuCy and allogeneic HCT is well tolerated with no unexpected TRM or differences in clinical outcomes.