The role of mycophenolate mofetil (MMF) is still controversial in the treatment of cyclophosphamide-resistant proliferative lupus nephritis (PLN). Enteric-coated mycophenolate sodium (EC-MPS) has less gastrointestinal adverse effects than MMF and is, therefore, increasingly utilised in organ transplantation. The aim of this study was to compare the efficacy and safety of EC-MPS versus an extended-course of intravenous cyclophosphamide (ED-IVCY) in resistant-type PLN. Thirty-one, biopsy-proven PLN, patients who failed to respond to an induction of IVCY were enrolled in a prospective, open-labelled, historically controlled study. Patients received 6 month of EC-MPS (720 mg b.i.d.) treatment. The patients in the ED-IVCY group, collected from a database, received a repeated 6-month course of monthly IVCY 0.5-1 g/m(2) of body surface area. Both groups received 0.5-1 mg/kg/day of prednisolone. Primary outcomes were partial or complete responses. A repeated kidney biopsy was performed to evaluate the histological response. No serious adverse events or patient deaths were observed during the study. Both groups had comparable baseline characteristics. At 6 months, the EC-MPS group had a comparable response rate with the ED-IVCY group. There were significantly less adverse events in the EC-MPS group. Repeated biopsies showed significant improvement in the EC-MPS group. EC-MPS provides salutary efficacy and safety in the treatment of resistant-type PLN and can be a suitably alternative treatment to ED-IVCY.