MSActiveSource

Tysabri

Tysabri (natalizumab)
Tysabri contains the active ingredient natalizumab, a monoclonal antibody. Antibodies are proteins produced by the body’s defence (immune) system. They detect foreign substances that invade the body.

Tysabri is used to treat adults with highly active relapsing remitting MS. It is used when the disease has failed to respond to treatment with a beta interferon or is severe and getting worse rapidly. Tysabri helps to reduce the number and severity of relapses and slows the course of the condition.

For more information about the course of MS go to Types of MS.

How Tysabri works
In MS, your body’s defence (immune) system attacks its own myelin – the ‘insulation’ that surrounds nerve fibres. When myelin is damaged, the messages between the brain and other parts of the body are disrupted. This is what causes the symptoms of MS. Tysabri is thought to work by binding to the body’s immune cells, which prevents them from passing from the blood to the brain. This helps to reduce inflammation around nerve cells and prevent nerve damage.

How is Tysabri taken?
Tysabri will be prepared and given to you by a doctor or nurse. The dose of 300 mg of Tysabri is first diluted in about 100 ml of solution (about half a cup in volume) which is given as a drip into a vein (intravenous infusion), usually in your arm. This takes about 1 hour and will happen once every 4 weeks.

More detailed prescribing information on Tysabri can be found by going to www.medicines.ie. Typing Tysabri in the search box and pressing Go will bring you to a patient information leaflet on Tysabri.

Tysabri is marketed by Biogen Idec Ltd and Elan Pharma International Ltd in the UK and Ireland.