BELIMUMAB (Benlysta)
Belimumab, marketed by Human Genome Sciences and GlaxoSmithKline as Benlysta, is a human monoclonal antibody that blocks a protein called B-lymphocyte stimulator (Bly S) responsible for the generation of autoantibodies, the hallmark of Lupus. Despite of its novelty, Belimumab is not exactly the type of drug therapy that Lupus patients are expecting because it cannot substitute definitely corticosteroids and because still remains unclear the benefit on severe renal or neurologic Lupus impairment. Nevertheless, is very welcome since it is the first drug approved by U.S. FDA for Lupus therapy since 1958 and it may helpful to reduce maintenance dose of corticosteroids. Belimumab is administrated intravenously every two weeks (first three doses) and then every 28 days. It has been reported serious reactions during infusion. Recommended Reading: Arthritis Rheum. 2009 Sep: 61 (9): 1168-1178; Curr Opin Rheumatol. 2011 February 16
RITUXIMAB (Mabthera, Rituxan)
Rituximab, marketed by Roche as Mabthera and as Rituxan by Genentech & Biotech, is an anti-CD20 chimeric monoclonal antibody that reduces humoral immune response by depleting B lymphocytes. B Lymphocytes are the immune cells that produce antibodies, therefore, B cell depletion implies decrease production of autoantibodies, the hallmark of autoimmune diseases. It is widely used in hematology to treat non-Hodgking’s lymphoma and chronic lymphocytic leukemia but it is also used in rheumatology to treat Lupus and rheumatoid arthritis. Rituximab, in combination with methotrexate, is indicated for the treatment of rheumatoid arthritis patients who have had an inadequate response to one or more TNF antagonist therapies. Rituximab requires intravenous administration on days 0 and 15 with retreatments every 6 months. Rituximab therapy can result in serious side effects some which can be life-threatening such as infusion reactions, severe mucocutaneous reactions or progressive multifocal leukoencephalopathy. Premedication may reduce the incidence and/or the severity of infusion reactions. It is not recommended for patients with severe active infections. Suggested readings: Arthritis Rheum. 2006; 54 (9):2793; Arthritis Rheum.2004; 50(8):2580