(Natalizumab)Biosimilar Reference Antibody-GS40461

货号：GS40461

Natalizumab (brand name Tysabri®) is a humanized monoclonal antibody that targets the α4 subunit of integrins, specifically α4β1 (VLA‑4) and α4β7. By binding to α4‑integrin, natalizumab blocks the adhesion of lymphocytes to vascular endothelial cells expressing VCAM‑1 and MAdCAM‑1, thereby preventing their migration across the blood‑brain barrier and into the intestinal mucosa. This inhibition reduces immune‑mediated inflammation in the central nervous system and gut. It is approved for the treatment of relapsing forms of multiple sclerosis (MS) and moderately to severely active Crohn’s disease (CD) in patients who have had an inadequate response to or cannot tolerate conventional therapies. Due to the risk of progressive multifocal leukoencephalopathy (PML) associated with JC virus reactivation, its use is subject to strict risk‑management protocols.