Importance: Rituximab induces B-lymphocyte apoptosis by targeting CD20 antigen and has shown efficacy in antibody-mediated autoimmune disease. Rituximab is increasingly being acknowledged as an effective and safe treatment option for pemphigus.
Objective: To assess the clinical response of patients with pemphigus to rituximab using a modified fixed-dose rheumatoid arthritis protocol (1 g intravenously on days 1 and 15, followed by 500 mg intravenously if clinically warranted at 6-month intervals or repeated full dosing).
Design, setting, and participants: A retrospective cohort study was conducted using records from a tertiary referral center for autoimmune bullous disorders. Participants included 92 patients (pemphigus vulgaris, 84 [91%], and pemphigus foliaceus, 8 [9%]) who received rituximab treatment between May 1, 2006, and August 30, 2012.
Main outcomes and measures: The primary outcomes were time to relapse and achievement of a complete response with or without treatment at the end of the study.
Results: Median time to relapse after the first treatment cycle was 15 months (95% CI, 10.3-19.7). All patients experienced improvement. Complete remission rates with or without adjuvant treatment at final follow-up were 89% (56 patients [61%] were in complete remission without treatment and 26 patients [28%] were in complete remission during adjuvant treatment). No serious infectious adverse events occurred.
Conclusions and relevance: The fixed-dose, modified rheumatoid arthritis protocol for rituximab was efficacious and well tolerated in patients with pemphigus. Patients who do not achieve remission after 1 cycle or patients who experience relapse benefit from further cycles of rituximab. Our results need to be confirmed in larger and controlled trials.