- Patients must have steroid refractory chronic GVHD, defined as having persistent signs and symptoms of chronic GVHD despite the use of prednisone at < 0.5 mg/kg/day or 1 mg/kg every other day for at least 4 weeks in the preceding 12 months (or equivalent dosing of alternate corticosteroids) without complete resolution of signs and symptoms. Patients with either extensive chronic GVHD or limited chronic GVHD requiring systemic therapy are eligible.