- Hematopoietic stem cell transplantation (SCT): Patients receive busulfan IV every 6 hours on days -9 to -6, high-dose cyclophosphamide IV over 1 hour on days -5 to -2, anti-thymocyte globulin IV once or twice daily over 4 hours on days -3 to -1, and methylprednisolone IV on days -3 to -1.