Rituximab is able to inhibit the B-cells in the pathogenesis of RA. The drug is a chimeric monoclonal antibody against the protein CD20 present on the B-cell surface. Rituximab destroys B-cells in the joints via different mechanisms, helping to reduce inflammation.

The exact function of CD20 is unknown, but it may play a role in Ca2+ influx across plasma membranes, maintaining intracellular Ca2+ concentration and allowing activation of B cells. The following effects of rituximab have been found:

Rituximab is used in the treatment of RA as well as in B cell non-Hodgkin's lymphoma and B-cell leukemias.

Serious adverse events, which can cause death and disability, include: severe infusion reactions, cardiac arrest, acute renal failure, infections, immune toxicity, and pulmonary toxicity.

EPAR of rituximab.