Rituximab: A Magic Bullet for Pemphigus

Introduction: Pemphigus, an autoimmune disease, was fatal before the era of corticosteroids. With the advent of steroids, mortality decreased but morbidity was present due to the side effects of high dose steroids. Newer drugs targeted at the molecular level are said to have fewer side effects and improved effectiveness.

Aim: The aim of our study was to assess the effectiveness of one such drug, Rituximab, a biological, in treating pemphigus vulgaris and to identify common adverse events.

Materials and methods: It was an open label prospective interventional study, conducted from September 2013 to May 2015, in the Department of Dermatology, Stanley Medical College, Chennai, Tamil Nadu, India. Twenty patients with pemphigus were included in the study. Ten were refractory to conventional therapy and 10, new cases. Patients who satisfied inclusion and exclusion criteria were included in the study after informed, written consent. Rituximab was administered according to Rheumatoid arthritis protocol. The patients were followed up as out patients after discharge, end points and adverse events were noted.

Results: There were 14 females (70%) and six males (30%). The mean age of the study group was 41.35 years. The mean disease duration was 11.7 months. The mean duration of follow up being 14.25 months. After rituximab, 13 patients remained in remission for varying periods of 3-22 months. The mean duration of complete remission off- treatment with Dexamethasone Cyclophosphamide Pulse (DCP) was 3.6 months; with rituximab it was 8.8 months. Seven (35%) patients relapsed during the study of whom six had received rituximab after being refractory to conventional treatment. Patients who relapsed had higher mean disease duration (21 months) than the remission group (6.384 months). Two patients (10%) developed immediate adverse events. Six patients (30%) developed late adverse events the commonest being reactivation of herpes labialis.

Conclusion: Rituximab was effective in treating pemphigus vulgaris, was significantly better than conventional treatment, decreased the need for additional steroids and other immunosuppressants and induced prolonged remission. Rituximab was more effective when given early in the disease process. Further studies may highlight the need for additional cycles of rituximab to maintain sustained remission.