r ATG 0.5 mg/kg given on day -5, then 1.0 mg/kg given on day -4, then 1.5 mg/kg given on days -3 through -1. r ATG is infused over 10 hours. Premedicate with Acetaminophen 650 mg po and Diphenhydramine 25 mg po/IV 30 minutes before the infusion.