Ph I/II Study of Allogeneic SCT for Clinically Aggressive Sickle Cell Disease (SCD)

"Alemtuzumab-based non-myeloablative allogeneic hematopoietic stem cell transplantation using immune-suppressive agents and low-dose total body irradiation (TBI) without standard chemotherapy.~Transplant regimen Day -7 to -3: Alemtuzumab (1mg/kg, total dose) divided over the 5 days, IVPB over 2 hours daily Day -3 until 100% chimerism obtained: Sirolimus dosed for target trough level of 10-15 ng/mL Day -2: Total body irradiation with 300cGy Day 0: Stem cell infusion"

In this protocol, patients will be given alemtuzumab 1mg/kg divided equally over five days with the maximum dose of 20mg per day.

On day -1, patients will receive a loading dose of 12 mg followed by 4 mg per day. Subsequent dosing will be based on clinical toxicity, GVHD concurrent medications, medical conditions, prior drug levels, drug-drug interactions, and blood levels with target of 3 to 12 ng/mL.