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Evaluating Your Risk of PML

Whether you're taking TYSABRI or considering it with your doctor, it's important to understand the benefits and the risks. First and foremost, we want you to know about 3 important considerations regarding TYSABRI:

  1. One of the risks of TYSABRI is progressive multifocal
    leukoencephalopathy (PML), a serious brain infection.
  2. The JC Virus Test can help identify the presence of the
    virus that can lead to PML.
  3. There are certain known risk factors you and your doctor should consider to help evaluate your risk of PML. There may be other risk factors that we do not know about yet.


Find answers to questions surrounding PML. What is PML? What causes it? How TYSABRI may increase your risk of PML. And how a blood test can help identify this risk.


Please read the information in each tab carefully, and remember to always discuss any concerns you have about treating your relapsing MS with your doctor.

Talk to Your Doctor
A productive conversation can help you and your doctor decide if TYSABRI may be right for you.
Ask these
Concerned About PML?
Learn how the TOUCH® Prescribing Program can help you monitor your safety.
Read more.
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Important Safety Information

Please see full Prescribing Information (PDF) , including Boxed Warning and
Patient Medication Guide (PDF) .

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