Treatment of refractory pemphigus vulgaris with rituximab (anti-CD20 monoclonal antibody)

Background: Pemphigus vulgaris (PV) is a severe antibody-mediated autoimmune blistering disease. Because some patients with PV do not enter into remission, despite the use of high-dose corticosteroid therapy and immunosuppressive adjuvant treatments, new effective and safer agents are warranted to treat refractory PV. Rituximab, a monoclonal anti-CD20 antibody, induces depletion of B cells in vivo and has shown efficacy in patients with refractory antibody-mediated autoimmune disorders. We describe herein 3 patients treated with rituximab for severe PV. Observations: Three patients with refractory PV were treated with rituximab, resulting in a clinical response in all patients, which was complete in 2 patients. A decline in titers of circulating antiepidermis autoantibodies paralleled disease activity, while circulating B cells remained undetectable for 6 to 10 months. Two patients experienced bacterial infection in the weeks following the rituximab course. A clinical relapse occurred in 2 patients, at 6 and 10 months. A second course of rituximab controlled the disease in one of them. Conclusion: These patients' response suggests that rituximab may be a valuable treatment for refractory PV and warrants further studies to evaluate the risk-benefit ratio in patients with PV showing resistance to classic therapy.