[Long-term prognosis of patients with steroid-dependent nephrotic syndrome treated with rituximab]

Rituximab, an anti-CD2O monoclonal antibody, is an emerging and effective option for the treatment of patients with refractory steroid-dependent nephrotic syndrome (SDNS), but few studies have assessed the long-term prognosis in these patients. We therefore evaluated the efficacy of rituximab in 35 patients, aged 4-21 years, who experienced SDNS while being treated with immunosuppressants. Patients were monitored for 24-63 months. After the first infusion of rituximab, the number of relapses and the dose of prednisolone were significantly reduced, and the steroid withdrawal period was significantly increased. However, 22 patients (63%) required retreatment with rituximab owing to relapses. At the last observation, only three patients (9%) could discontinue immunosuppressants completely and only three continued to show remission during the observation period. Although rituximab could not induce a complete cure of refractory SDNS, it resulted in longer remission times when immunosuppressants were continued after rituximab therapy, indicating the effectiveness of rituximab followed by immunosuppressants. We also found that patients who experienced more relapses before rituximab therapy were more likely to relapse earlier after rituximab therapy.