Vitamin C With Steroids for Gastrointestinal GVHD

"All patients enrolled on this trial will receive steroids at a minimum dose of prednisone 2 mg/kg/day PO (or methylprednisolone 1.6 mg/kg/day IV) divided into 1-2 daily doses as therapy for acute GVHD. For patients that weigh over 100 kg, maximal starting dose of prednisone will be 200 mg (or methylprednisolone-equivalent).~Patients will be treated with intravenous (IV) or oral (PO) vitamin C depending on the severity of symptoms, ability to tolerate PO intake, and location of treatment (inpatient versus outpatient setting): IV dosing:~50 mg/kg/day divided TID (max 4 grams total/day) PO dosing: 500 mg BID or 1000 mg daily (depending on the prescribed formulation)~Vitamin C will be administered through day 56 from start of vitamin C treatment. Patients initially receiving IV administration may be transitioned to PO formulation once tolerating PO intake; per treating physician discretion."