Facts About Tysabri and PML

Tysabri patients have been developing progressive multifocal leukoencephalopathy (PML), a frequently fatal brain infection.

Tysabi patients have been developing progressive multifocal leukoencephalopathy (PML), a rare brain infection which can cause difficulty with walking and other movements, decline in mental function, and problems with vision and speaking. The symptoms of PML may begin gradually, usually worsen rapidly, and can vary depending on which part of the brain is infected. PML is often fatal, and there is no known cure.

Tysabri has been prescribed for patients with Multiple Sclerosis and Crohn's disease. Both of these conditions are tragic and debilitating, but the treatment shouldn't be worse than the disease.

Tysabri and PML

Tysabri was approved for patients with Multiple Sclerosis and Crohn’s disease in November of 2004, and then withdrawn from the market in February 2005 after reports of patients who had taken Tysabri being diagnosed with, and subsequently dying form, progressive multifocal leukoencephalopathy. The FDA put a temporary hold on the drug, only to resume clinical trials of Tysabri in February of 2006.

Tysabri was allowed back on the market in June 2006 with increased restrictions and enhanced safety warnings, including a black box warning about the dangers of PML.

Tysabri has been a highly profitable drug for Biogen, with 48,800 patients on Tysabri paysing as much as $28,000 per year for the treatment. Biogen has been aggressively marketing Tysabri, to the point that the company received a warning letter from the FDA about its marketing of Tysabri, which the FDA called false and misleading, and which minimized important risks associated with the drug.

How does Tysabri Cause PML?

Neither the exact way Tysabri acts on MS patients nor the way it causes PML are fully understood. Scientists think that Tysabri seems to affect Multiple Sclerosis patients by acting on T-Cells, a part of the body’s immune system. In MS patients, these T-Cells malfunction and actually attack the patient’s own nervous system. Tysabri prevents T-Cells from performing their full function in an attempt to halt this damage. Tysabri’s effect on the immune system may be the mechanism that also makes Tysabri patients prarticularly vulnerbale to PML. PML is caused by a common virus that as many as 80% of the people on the planet have been exposed to. Normally, the body’s immune system can easily fight off this virus. But when Tysabri interferes with the function of T-Cells, it seems to make the body much more vulnerable to infection by the virus that causes PML.

Further Risks of Tysabri

Tysbari carries further risks than just PML. In the years since Tysabri has been on the market, there have been further warnings issued by the FDA about Tysabri, including the possibility of liver damage and immune function disorders.

Tysabri Lawsuits

Individuals and families who have been harmed by the dangerous side effects of Tysabri are beginning to file lawsuits to seek compensation for their injuries. If you have been diagnosed with progressive multifocal leukoencephalopathy as a result of taking Tysabri, the law firm of Blizzard & Nabers will work with you to file a Tysabri lawsuit. Our firm is experienced in pharmaceutical law. For more than 25 years, our attorneys have successfully represented our clients and stood up for the rights of people harmed by pharmaceutical companies and dangerous drugs. We are a nationwide law firm serving clients from all over the country. We handle all Tysabri-related injury cases on a contingency basis.

To learn more, or for a free case review from an experienced Tysabri attorney, please contact us by email or call us at 1-800-349-0127.