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A 37-year-old member asked:

Can you tell me about having multiple sclerosis and being tested for the jc virus before starting tysabri (natalizumab)?

1 doctor answer2 doctors weighed in
Dr. Bennett Machanic
Neurology 52 years experience
SEQUENCE: Tysabri (natalizumab) is most potent MS drug on market, but risk of PML approaches 1 in 90, if 2 yrs of usage, prior chemotherapeutic agents, and positive anti-JCV index test. However, in many others with negative testing, risk is less than 1 in 40,000 at 2 yrs. Positive test does NOT exclude Tysabri (natalizumab), but maybe stop at 18-24 months, and switch to Gilenya at that point.

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United Kingdom (Great Britain)
A 31-year-old female asked:

I have multiple sclerosis, should I take tysabri (natalizumab)? For my medication

2 doctor answers5 doctors weighed in
Dr. Bennett Machanic
Neurology 52 years experience
Complex : Tysabri (natalizumab) is the most effective medication currently on the market, but has a risk of a bad infection "pml". If you are having progressive problems, such as relapses, or your MRI studies show more lesions, you may well need more potency, especially if you are taking Avonex or copaxone. But all ms pts are different, and a variety of choices are present. An ms specialist can help.

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Last updated Jun 25, 2014

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