Unexpected worsening of pemphigus vulgaris after rituximab: A report of three cases.

During the recent decade, several studies have confirmed the high efficacy of targeting the CD20 molecules using rituximab (RTX). Recently, RTX has been suggested as the first-line treatment of pemphigus vulgaris (PV). In this study, the records of all the PV patients, who had received RTX in Autoimmune Bullous Diseases Research Center, Tehran University of Medical Sciences between the 2009 and 2017, have been reviewed for any sign of disease worsening within three months after treatment. We have observed three PV patients from 612 RTX-exposed patients, who had experienced worsening of disease more than one time after discrete RTX cycles after the first infusion of RTX. All patients were successfully managed with different strategies (e.g., increase in steroid dosag intravenous immunoglobulin [IVIg], and plasmapheresis). In conclusion, despite the high efficacy of RTX therapy in PV patients, the exceptional risk of post-RTX disease worsening exists. Further studies are encouraged to develop (bio)markers to predict possible unexpected worsening of PV patients exposed to RTX.