Rituximab as an adjuvant therapy for pemphigus: experience in 61 patients from a single center with long-term follow-up

Background Rituximab is increasingly being used as an adjuvant treatment for recalcitrant or relapsed pemphigus, but information on its use as a first-line agent is limited. We describe the long-term effectiveness and safety of rituximab in the treatment of pemphigus and compare the treatment outcomes when rituximab is used as first-line treatment vis-a-vis after treatment failure or relapse. Methods This was a retrospective review of 61 patients with pemphigus treated with rituximab at our center from March 2012 to October 2018. Results Of the 61 patients, 51 achieved complete remission (on or off treatment) and 10 had partial remission. Forty-nine (80.33%) patients achieved complete remission off prednisolone over a mean period of 8.08 +/- 4.45 (range 3-20) months. Seventeen (27.9%) patients relapsed after a mean period of 23.94 +/- 13.15 months after first rituximab cycle and 15.97 + 13.7 months after stopping prednisolone. Treatment-related serious adverse effects were noted in six (9.8%) patients. Eighteen (29.5%) patients were administered rituximab as the first-line adjuvant, while 43 (70.5%) patients received it after treatment failure or relapse. In both groups, remission rates on prednisolone (88.9%, 81.4%) and off prednisolone (88.9%, 76.7%) were comparable (P > 0.05). Relapse rates in the group which received rituximab as first-line treatment were about half of those who received rituximab after relapse or treatment failure (16.7% vs. 32.6%, P = 0.348). No statistically significant difference was seen in the times to different treatment endpoints (disease control, complete remission on and off prednisolone, and relapse) between the two groups. Conclusions Rituximab is a safe and effective adjuvant in the treatment of pemphigus. Treatment outcomes were better for patients who received rituximab as first-line treatment, but the difference was not statistically significant.