Interior web banner image


What is Tysabri?

Tysabri is a drug used as single therapy (monotherapy) for the treatment of patients with relapsing forms of multiple sclerosis (MS) to reduce the frequency of attacks and delay worsening of physical disability.

How Does it Work?

Tysabri (natalizumab) is a monoclonal antibody produced in the laboratory and designed to curb the movement of potentially damaging white blood cells (immune cells) from the bloodstream into the brain and spinal cord. It works by binding to a protein found on the surface of the immune cells, which prevents them from crossing the “blood-brain barrier” of the central nervous system.

Tysabri is given intravenously over about an hour and treatments are done every four weeks.