Conditioning regimen. All patients received alemtuzumab, 400 cGy TBI, and sirolimus. Cohort 1 patients received no PT-Cy, cohort 2 patients received 50 mg/kg PT-Cy, and cohort 3 patients received 100 mg/kg PT-Cy. Sirolimus target level was 10 to 15 ng/dL. Sirolimus was started 1 day before PBSC infusion in patients 4 through 9 and 4 days posttransplant in patients 10 and 11. IV, intravenous; N/A, not applicable.