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Taking Tysabri if you test positive for JC Virus
lsmith31279 posted:
I was diagnosed with MS 7 years ago and other than my initial problems, I have been basically symptom free for the last 6 years until the last two months in which I seem to be making up for lost time! I am now unable to walk, drive, work or basically do anything productive. I am seeing a wonderful new neurologist who specializes in MS. I really like the doctor but he thinks I should go on Tysabri for one year even though I have tested positive for the JC virus. He seems to think that the Tysabri will be my only hope of regaining my mobility and ability from before this last month or two. I would appreciate any advice or insight!
hackwriter responded:
Dear Ismith,

Your risk for developing PML while JCV positive in the first two years on Tysabri is 1/1000. Your chances increase slightly if you stay on the drug through years 3-4.

If you are JCV positive and you have taken immunosuppressant therapy prior to Tysabri, the risk increases, but it is whether you possess all three risk factors for PML that the risk becomes a bit more significant.

I'm guessing that you have not taken immunosuppressant therapy since your doc has recommended taking Ty for the shortest duration.

Here's the link that explains the risk of developing PML on Tysabri if you are JCV positive, it has a table at the bottom of the page showing how risk increases if you possess all three risk factors for PML:

Each patient must weight the risks and benefits in this situation. There are a number of patients who are JCV positive and who have chosen to stay on Tysabri because it is helping them. I hope one of them will respond to your post.

Soonerslp responded:
I have been diagnosed 12 yrs and did great until after I had a baby. Now I am in your shoes and am unable to work, drive, etc. I have been on All the medications and decided to go to the MS Center at the Cleveland Clinic. The dr also recommended tysabri saying that it is the best one and I should see great results.I am also positive for the virus. They said of the thousands they have had on it, only one has gotten pml. The way to fi it is to stop the med. she had stroke like symptoms but is now doing well. I met a young lady who is also positive and has been on it 5yrs! She feels great nd doesn't want to get off despite the dr's recommendation. My dr there said a 2 yr period is safe but wouldn't go past that, hope that helps.

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