- Refractory disease defined as continuing extension of old lesions, development of new lesion, or failure of established lesions to begin to heal despite 3 weeks of therapy on 1.5 mg/kg/day of prednisolone or its equivalent with or without the concurrent use of cyclophosphamide 2mg/kg/day for 12 weeks or azathioprine 2.5 mg/kg/day for 12 weeks. Patients who fail to respond to 6 DCP/DP are also considered as refractory disease.