Rituximab indications in dermatology, efficacy and adverse effects: retrospective study in a tertiary care hospital in Sri Lanka and review of literature

Introduction and objectives: Rituximab induces B lymphocyte apoptosis by targeting CD 2O antigen and has shown efficacy in antibody mediated autoimmune diseases. It is increasingly recognized as an effective and safe treatment option for pemphigus and other autoimmune disorders.

To determine the efficacy and adverse effects of adjuvant rituximab using the lymphoma protocol (375 mg/m² intravenously on days 0, 7, 14, 21).

Materials and methods: A retrospective cohort study was conducted using records from the Dermatology Clinic in the Teaching Hospital Kandy. Participants included 23 patients (pemphigus vulgaris, 16 (69%), pemphigus foliaceus, 1 (4.3%), epidermolysis bullosa acquisita, 1 (4.3%), bullous pemphigoid, 1 (4.3%), systemic lupus erythematous, 3 (13%), dermatomyositis, 1 (4.3%), who received rituximab treatment between May 1,2010, and December 30,2016.

Main outcomes and measures: Results were analysed in two sub groups; autoimmune blistering diseases (AIBD) and connective tissue diseases (CTD). In the autoimmune bullous disorder group, the primary outcomes were response to treatment at 3 months, 6 months and at the end of the study, (achievement of complete remission with or without treatment) and the time to relapse. In the connective tissue disease group mean steroid dose at 3 and 6 months was used as a surrogate marker for disease activity.

Results: In the AIBD group all patients experienced remission. Complete remission rates without treatment at final follow up was 88.8% (16/18) in the immunobullous group. All patients in the connective tissues disorder group were in partial remission and on prednisolone, mean dose of 17.5mg at 3 months and 10 mg at 6 months. Median time to relapse after the first treatment cycle was 15 months.