Natalizumab for Multiple Sclerosis

A 30-year-old woman with relapsing–remitting multiple sclerosis presents for consideration of treatment with natalizumab after several first-line treatments have failed. Natalizumab has been shown to reduce the rates of relapse and disease progression in multiple sclerosis. However, use of this agent is restricted because of the risk of progressive multifocal leukoencephalopathy, a serious central nervous system disorder.