Therapy with rituximab for autoimmune pemphigus: Results from a single-center observational study on 42 cases with long-term follow-up

Background: Rituximab induces depletion of B cells and has shown efficacy in antibody-mediated autoimmune disorders. In studies on small series of patients with pemphigus, rituximab administration results in significant improvement. However, differences in inclusion criteria, treatment protocols, and follow-up make it difficult to derive uniform conclusions. Objectives: We sought to test the efficacy and tolerability of rituximab as adjuvant therapy to corticosteroids in the treatment of pemphigus. Methods: In all, 42 patients with pemphigus were treated with rituximab and followed up for up to 5 years. No additional immunosuppressive agents were used. Steroids were rapidly tapered. Outcomes were the proportion of patients who achieved a complete response on or off therapy, the rate of discontinuation of corticosteroid within 6 months, length of remission, time to relapses, and occurrence of adverse events. Results: In all, 36 of 42 patients (86%; 95% confidence interval 75%-96%) achieved a complete response on or off therapy and discontinued steroids within 6 months from induction therapy. Six patients had a complete response off therapy with an additional infusion of rituximab 6 months after initial treatment. Twenty patients experienced a total of 34 relapses; the time to relapse was 8 to 64 months. Every relapse was treated with rituximab (500 mg) without corticosteroids, which induced a new complete response. No serious adverse events were observed. Limitations: Lack of a control group is a limitation. Conclusions: Rituximab therapy induces prolonged clinical remission in patients with pemphigus. Coadministration of other immunosuppressive agents is not necessary. Relapses can be managed with additional infusions administered on demand.