Brands, Medical Use, Clinical Data
Brands / Synonyms
Anti-alpha4 integrin; Anti-VLA4; Tysabri; Tysabri (Antegren) Biogen & Elan Corp
Humanized IgG4k monoclonal antibody produced in murine myeloma cells. Natalizumab contains human framework regions and the complementarity-determining regions of a murine antibody that binds to a4-integrin
For treatment of multiple sclerosis
In multiple sclerosis, lesions are believed to occur when activated inflammatory cells, including T-lymphocytes, cross the blood-brain barrier (BBB). Leukocyte migration across the BBB involves interaction between adhesion molecules on inflammatory cells, and their counter-receptors present on endothelial cells of the vessel wall. The clinical effect of natalizumab in multiple sclerosis may be a secondary result of its blockade of the molecular interaction of a 4b 1-integrin expressed by inflammatory cells with VCAM-1 on vascular endothelial cells, and with CS-1 and/or osteopontin expressed by parenchymal cells in the brain.
Mechanism of Action
Binds to the α4-subunit of α4b 1 and α4b 7 integrins expressed on the surface of all leukocytes except neutrophils, and inhibits the α4-mediated adhesion of leukocytes to their counter-receptor(s).
Biotrnasformation / Drug Metabolism
Most likely removed by opsonization via the reticuloendothelial system when bound to leukocytes.