Tysabri^®

What is Tysabri®?

Tysabri® (natalizumab) treats relapsing forms of multiple sclerosis in adults. It is a strong MS treatment, and it works differently from most others.

Most MS drugs lower the number of immune cells in your body. Tysabri does not. Instead, it stops those cells from getting into your brain and spinal cord in the first place.

There is something important to know before you start. Tysabri carries a risk of a rare brain infection called PML, and because of that it is only available through a special safety program. Read the safety section below carefully.

Tysabri is given at our MS Infusion Therapy | Rocky Mountain MS Clinic:

• Your dose: 300 mg

• How often: Once every 4 weeks

• Total appointment time: About 2 to 3 hours

A nurse will watch you for about an hour after your treatment, especially during your first year. After about a year of treatments without problems, your doctor may shorten that time.

How does Tysabri work?

Your brain and spinal cord are protected by a barrier. Think of it like a security gate. It keeps most things in your blood from getting through.

In MS, immune cells push through that gate. Once they are inside, they attack the protective coating around your nerves. That coating is called myelin, and damaging it is what causes MS symptoms.

Tysabri works at the gate instead of inside your body. Your immune cells stay in your blood, where they can still do their normal job of fighting infection.

Here is what it does:

• Immune cells use a grabbing tool to get through the gate. It is a surface protein called alpha-4 integrin.

• Tysabri covers that tool. It attaches to the protein so the cell cannot grab on.

• The cells cannot get in. They stay in your bloodstream instead of entering your brain.

• Swelling goes down. With fewer immune cells reaching your brain and spinal cord, there is less damage to myelin.

Tysabri starts working after your very first treatment. Many people notice a difference within about 3 months.

Like other MS treatments, its job is to prevent new damage rather than fix damage you already have. Some people have a rough patch in the first few months as their body adjusts. That usually settles down.

Common side effects:

• Headache

• Feeling tired

• Sore joints

• Upset stomach

• Bladder infections

• Colds and chest infections

• Feeling down or depressed

• Rash

Serious side effects — get medical help right away:

• PML (BOXED WARNING). This is short for progressive multifocal leukoencephalopathy. It is a rare brain infection that can be deadly. Your risk goes up if you carry a common virus called the JC virus, if you have been on Tysabri a long time, or if you have taken other immune-suppressing drugs before. You will have a blood test for the JC virus before you start and from time to time afterward. Tell your doctor right away if you notice new clumsiness, memory problems, vision changes, trouble speaking, or weakness on one side.

• Special safety program. Tysabri is only available through a program called TOUCH. Your doctor and the infusion center both have to be enrolled, and you will be monitored throughout treatment.

• Severe allergic reactions. Hives, itching, trouble breathing, chest pain, or swelling of your face, lips, or tongue, during or after treatment.

• Liver damage. Yellow skin or eyes, dark urine, or belly pain.

• Herpes infections. These can affect your brain, the lining around your brain, or your eyes.