Phase I/II Study of Pentostatin Combined With Tacrolimus and Mini-Methotrexate for GVHD Prevention After MUD BMT

"Given intravenously on days +8, +15, +22 and +30 post transplant:~Group 2 - Pentostatin 0.5 mg/m\^2~Group 3 - Pentostatin 1 mg/m\^2~Group 4 - Pentostatin 1.5 mg/m\^2~Group 5 - Pentostatin 2 mg/m\^2"

Given intravenously from day -2, and will be switched to oral dosing when tolerated.

Given intravenously on days +1, +3, and +6 at the dose of 5 mg/m2.