Infusion-Related, Short-term, and Delayed Side Effects of Rituximab in Multiple Sclerosis and Neuromyelitis Optica Spectrum Disorder

Abstract

Background: Rituximab is a monoclonal antibody against CD20 antigen present on mature B lymphocytes. It is commonly used in some hematologic, rheumatologic as well as neurologic disorders, including multiple sclerosis (MS) and neuromyelitis optica (NMO). Although there are some data about the safety of rituximab in patients with MS and NMO, there are few experiences regarding its safety in the Iranian population with MS, and known complications are often related to the studies conducted on the patients in other countries or with other autoimmune diseases and malignancies that are different from the population of patients with MS in terms of the underlying disease status and the concomitant medications or previous medications used. Objectives: The aim of this study was to investigate the infusion related, short-term and delayed side effects of rituximab on patients with MS and NMO in the population of the south of Iran. Methods: This was a longitudinal study on patients with MS and neuromyelitis optica who were referred to the health centers affiliated to Shiraz University of Medical Sciences from September 2018 to February 2019 and received Rituximab. They were observed for side effects from the first infusion of the drug to at least 6 months later. A checklist prepared by the researcher was used to collect the data. Independent t-test and chi-square test were used for data analysis. The significance level was considered 0.05 in this study. Results: In this study, 37% of the patients had at least one side effect during the first infusion. The most common side effect was chills (shivering). Short-term side effects occurred in 15.5% of the patients. The most common type was skin manifestations. These side effects led to hospitalization in two patients. Delayed side effect was developed in 20.7% of the patients. The most common delayed side effect was skin manifestations. Conclusions: Overall, there was no unexpected side effect in patients under the study and the side effects developed were comparable to previous studies as well as those conducted on patients other than patients with MS and neuromyelitis optica. Side effects were often mild, with only two cases leading to hospitalization, both of which were self-limiting as well, and there were no serious life-threatening side effects, except for one case with bradycardia.