Abstract
INTRODUCTION: Membranous nephropathy (MN) is a common cause of nephrotic syndrome (NS) in adults. Without treatment, two-thirds of patients with MN develop nonprogressive chronic kidney disease or end-stage renal disease within 10 years. Obinutuzumab (OBZ), which binds to CD20 and leads to a pronounced depletion of B cells, may elicit a better therapeutic response in patients with refractory MN who do not respond to rituximab or who have recurrent episodes. METHODS: We describe two MN patients, one positive and one negative for the M-type phospholipase A(2) receptor antibody (PLA(2)R Ab). Both patients had poor responses to rituximab, but had different responses to OBZ. RESULTS: The patient positive for PLA(2)R Ab had an immunologic response, and the patient negative for PLA(2)R Ab had a nearcomplete clinical response. DISCUSSION: OBZ appears to be a suitable alternative when other treatment options are ineffective or contraindicated. The efficacy of OBZ for treatment of refractory MN needs to be verified by large-scale multicenter clinical trials.