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texasmad posted:
I am a 52 yr old male with what my doctor calls malignant MS which I guess means primary progressive in over-drive. I have been diagnosed for only 3 years officially but during that time have seen the use of my legs go and developed a persistent shake to my left arm. The last two years I have been on Tysabri and just had a rather large episode during which time they did blood work and for the first time I came back with a positive on my JC virus and my Physician has told me I can either take a chance and continue with Tysabri or a choice of only two other meds oneof which he said is hard to get approved and the other he said will make me sick for a month and possibly ruin my vision, both of these he stated were oral. He said none of the injectables are going to be strong enough to help me, is this really the only choices I have when facing a possibility of PML to stay with my current med?
hackwriter responded:
Dear texasmad,

I'm not aware of any approved therapies for primary progressive MS, so you were using Tysabri off-label (it is only approved to treat the relapsing form of MS), and the other meds your doc has in mind sound experimental and/or off-label as well. That's why he said it would be hard to get approved.

You have some difficult choices, obviously. Be aware that your risk of getting PML will increase only slightly now that you've passed the 2-year mark on Tysabri--but also be aware that your risk of getting PML is still quite low.

Your risk is highest if you fulfill all three of the following risk factors:

1. The presence of anti-JCV antibodies.

2. Longer duration of Tysabri treatment, especially beyond 2 years.

3. Prior treatment with an immunosuppressant medication (e.g., mitoxantrone, azathioprine, methotrexate, cyclophosphamide, or mycophenolate mofetil).

And here's a quote from the NMSS (see link below for more info):

A person who tests positive for anti-JCV antibodies but has no other risk factors has a less than 1 in 1000 risk of developing PML. A person with all three risk factors has an 11 in 1000 risk of developing PML.

This means that if you did not take an immunosuppressant therapy prior to Tysabri and you have developed JCV antibodies while on Tysabri, you risk remains at around 1 in 1000.

Hope this helps, texasmad. Please keep in touch and let us know what you've decided.

For more info about Tysabri and PML, see the following link:


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