Drug spotlight on Rituxan (rituximab)

Developed by Genentech/IDEC, Rituxan® (rituximab) is a genetically engineered molecule derived from a mouse antibody designed to kill B lymphocytes. B lymphocytes, or B cells, are the white blood cells that are responsible, in part, for autoantibody production -- the production of antibodies against ""self"" which is the hallmark of lupus.  B cells also produce certain proteins that can promote inflammation. While B lymphocytes are a chief component of the normal immune system, they are overactive in people with lupus.

Rituxan was initially developed for use in people with lymphoma (a type of B lymphocyte cancer), but the drug was subsequently approved for treating rheumatoid arthritis.  Several clinical research studies looked at the use of  Rituxan and a second generation antibody, known as ocrelizumab, to treat people with either lupus or lupus nephritis (lupus kidney disease).  However, these clinical trials were not successful.  

Many doctors still feel that Rituxan may be effective for certain manifestations of lupus and that the clinical trial failures were, in part, related to issues with trial design.  A study of Rituxan as a treatment for people with vasculitis, an inflammatory condition of the blood vessels, led to approval of Rituxan for “ANCA-associated vasculitis.”  Thus, Rituxan is now approved by the Food and Drug Administration as a treatment for rheumatoid arthritis and vasculitis.  Rituxan may have a role for certain individuals with lupus, and further clinical research is being pursued.