Primary membranous nephropathy (PMN), an autoimmune disease mostly associated with anti-phospholipase-A2-receptor (PLA2R) antibodies, is one of the most common causes of nephrotic syndrome in adults. In 30% to 40% of all cases, patients with PMN undergo spontaneous remission with conservative approaches. Corticosteroids, alkylating agents and calcineurin inhibitors are recommended treatment options in persistent disease activity despite supportive therapies. Nevertheless, patients with refractory disease constitute an important clinical aspect of PMN, and uncontrolled proteinuria may culminate in rapid progression to end-stage renal disease. In recent years, several studies demonstrated the efficacy of rituximab as a treatment option in patients with refractory PMN; however, data regarding daily clinical practice of this agent is still needed. Therefore, we conducted a study using our registry data to evaluate the efficacy and safety of rituximab in patients with refractory PMN.

Inclusion Criteria:

• Having biopsy-proven primary membranous nephropathy.
• Showing resistance to at least one set of prior therapies including corticosteroids, alkylating agents or calcineurin inhibitors.
• Having a history of rituximab use (375 mg/m2/wk for 2-4 weeks) following resistance aforementioned agents.

Exclusion Criteria:

• Not providing or withdrawing consent.

Patients with primary membranous nephropathy who were treated using rituximab following resistance to at least one set of prior therapies including corticosteroids, alkylating agents or calcineurin inhibitors.