The cost of care

We can help you find the most affordable way to start receiving TYSABRI

Circumstances change. Finances go up and down. Sometimes, these things are uncontrollable and unavoidable. At Biogen, we want you to know that if you need TYSABRI® (natalizumab), we will do our best to get you TYSABRI.

Understanding insurance coverage isn't easy

Whether you're uninsured, privately insured, or insured through a public payer (such as Medicare), the TYSABRI ActiveAccess™ Financial Program is tailored to your individual needs.

MS ActiveSource® Coordinators are available to help you with financial and insurance questions at 1-800-456-2255, Monday to Friday, 8:30 AM to 8:00 PM (ET). Whether it is out-of-pocket costs, copays, deductibles, or anything related to your insurance coverage—we'll be there for you.


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TYSABRI® (natalizumab) is a prescription medicine used to treat adults with relapsing forms of multiple sclerosis (MS) to slow the worsening of symptoms common in people with MS and to decrease the number of flare-ups (relapses). TYSABRI increases the risk of progressive multifocal leukoencephalopathy (PML). When starting and continuing treatment with TYSABRI, it is important to discuss with your doctor whether the expected benefit of TYSABRI is enough to outweigh this risk.

Important Safety Information

TYSABRI increases your risk of getting a rare brain infection—called progressive multifocal leukoencephalopathy (PML)—that usually leads to death or severe disability.

Before receiving TYSABRI, it is important to tell your doctor:
TYSABRI can cause serious side effects. If you have any of the symptoms listed below, call your doctor right away:
The most common side effects of TYSABRI are:
These are not all of the possible side effects of TYSABRI. For more information, ask your doctor. To report side effects to FDA, please call 1-800-FDA-1088.

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

This information is not intended to replace discussions with your healthcare provider.