A Narrative Review on the Effect of Rituximab on Secondary Humoral Immune Response

Abstract

Rituximab is a chimeric monoclonal antibody with binding specificity to CD20-positive B lymphocytes. Patients administered rituximab would not have adequate humoral response to the SARS-CoV-2 vaccine. Rituximab can also affect the durability of immunization. Plasma-secreting antibodies and memory B-cells are two major arms of long-term immunity. The role of memory B-cells becomes prominent by decreasing antibody titers over time. The activated memory B cells have CD20 protein on their surface. Investigating the effect of rituximab on other vaccines has demonstrated attenuated recall response. The evidence in this review suggests that we can also expect a deficit of recall response to SARS-CoV-2, making the ritux- imab-treated patients susceptible to reinfection with emerging variants. Therefore, it is better to consider other therapeutic options, use lower rituximab doses, and employ booster vaccines at shorter intervals.