Tysabri, Multiple Sclerosis (MS) pharmaceutical drug

In November 2004, Biogen Idec Inc. and Elan Pharmaceuticals Inc., received approval from the FDA to market and distribute Tysabri (natalizumab), a new Multiple Sclerosis (MS) drug. Only four months later, February 2005, the drug was quickly removed from the market after the FDA received several reports of severe illness and death in patients prescribed Tysabri and Avonex.

In several cases, the patient or corpse was allegedly diagnosed with Progressive Multifocal Leukoencephalopathy (PML), a rare brain infection that directly affects the central nervous system. Symptoms of PML are similar to a stroke: headaches, memory loss, speech and vision difficulties, limb weakness, and partial paralysis; the disease leads to coma then to death.

To date, approximately 8,000 patients have been involved in clinical trials or prescribed Tysabri for multiple sclerosis, Crohn's disease and rheumatoid arthritis. It is alleged that many patients with MS were persuaded to participate in these drug trials even if their symptoms were minimal and they did not need the drug.

Biogen Idec and Elan Pharmaceuticals hope to redistribute the drug after extensive evaluations of Tysabri and the possible link to the deadly infection, PML. Other known side effects of Tysabri include depression, urinary tract infection, lower respiratory infection, joint pain, fatigue, and headache.

The billion-dollar company, Biogen Idec, based in Cambridge, Massachusetts, also has another MS drug in the news: the bread-winning drug, Avonex, the most widely prescribed Multiple Sclerosis drug in the world with revenues of $1.4 billion in 2004 has recently been linked to increased risk of liver damage and liver failure.

Tysabri In the News

FDA votes to re-release Tysabri despite concern over rare, but deadly, side effects. If regulators move forward with this decision, Tysabri will be the second prescription drug in history to return to the shelves after a major drug recall. Surprisingly regulators are aware that this may result in additional MS patient deaths - one out of 1,000 patients may develop PML. A black-box warning may be added to the drug's label. (Mar-08-06) [MARKET WATCH]

The risk of a rare brain disease and other infections remains the primary concern of federal regulators as they seek independent advice on whether to allow a promising multiple sclerosis drug back on the market. (Mar-06-06) [MIAMI HERALD]

Biogen Idec Inc.'s multiple sclerosis drug Tysabri produced signs of fatal nerve disease. On February 28th the drug was withdrawn from the market after three fatal cases from progressive multifocal leukoencephalopathy. The U.S. Food and Drug Administration disclosed a possible fourth fatal case in the first week of June. (June-09-05) [BLOOMBERG]

FDA's Public Health Advisory for Tysabri

Register your Tysabri Drug Complaint

If you or a loved one suffered side effects from Tysabri, you may qualify for damages or remedies that might be awarded in a possible Tysabri class action or lawsuit, please fill in our form on the right to submit your complaint.
Last updated October 30 2008

Reader Comments

Posted by

Hi, I have relapsing-remitting M.S. and I took Tysabri for a year. My neurologist took me off of it when I developed a horrible case of cellulitis in my leg that caused me to be immobilized and in a wheelchair for 2 months. After cellulitis, the skin on my leg still flakes and peels.

Posted by

I am 52 , I was on tysabri from 2009 until 2017, I am jc positive. I was diagnosed with stage 2 seminoma in June of 2017.

Posted by

My late wife was infused with the drug Tysabri a couple of times in 2010 for her MS disease, on 1/11/11 she passed away. After receiving this drug her health declined very rapidly until her death.

Posted by

I was on Tysabri from 2007 till Feb of this year. I was tested for JC virus antibodies on a regular basis. I always tested neg. New stratified test tested pos. I went off then found out the deck was stacked as the test should have been available much earlier but the company that developed it was bought out by Tysabri manufacturers. This should be a lawsuite for corruption.

Posted by

I lost my vision. My vision went from 20x40 to 20x200 and 20x300 after the rebound effect when I quit taking it. I need an attorney!

Posted by

Within months of the reaction (and obviously no more Tysabri) I became wheelchair bound. This was in 2007, and I am still wheelchair bound today.

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