PML Risks Rise with More Tysabri Infusions

February 5, 2010

(Reuters) – Lisa Richwine – WASHINGTON – Fri Feb 5, 2010 1:34pm EST

The risk of a potentially fatal brain disorder (PML) with Biogen Idec Inc’s multiple sclerosis drug Tysabri increases as patients receive more infusions, U.S. health officials warned on Friday.

The prescribing instructions for Tysabri will be updated to warn of the higher risk with more treatment, the Food and Drug Administration said. Elan Corp co-markets the drug.

The FDA said the warning was based on 31 confirmed cases of progressive multifocal leukoencephalopathy (PML), a brain infection that can be fatal. Eight patients have died.

“Based on the available information, the FDA believes that the clinical benefits of Tysabri continue to outweigh the potential risks,” the FDA said in a notice on its website.

Tysabri was temporarily withdrawn from the market in 2005 because of its link to PML.

Biogen spokeswoman Naomi Aoki said “there was nothing I thought was new” in the FDA notice.

“Either it was included as part of our last label update or it was information that we are making available on a monthly basis,” she said.

Biogen updates the number of PML cases each month to doctors on request but no longer posts the figure on its website or issues a press release.

Elan officials were not immediately available for comment.

Tysabri is given as a single infusion every four weeks. About 66,000 people worldwide have been treated with the drug since it reappeared on the market in 2006, the FDA said.

The PML rate for patients given at least one infusion is 0.5 cases per 1,000 patients, the FDA said. For patients given at least 24 infusions, the PML rate is 1.3 per 1,000.

The FDA move comes two weeks after a similar announcement by European regulators, who also said Tysabri’s benefits outweighed risks.

The drug carries a boxed warning, the strongest type for prescription drugs, about the PML risk. All patients must enroll in a monitoring program for PML or other serious infections called: “The Touch Program”. The drug’s generic name is natalizumab.

Tysabri PML Lawyer

If you or a family member has been diagnosed with PML, or been treated with Tysabri infusions, contact our law firm to speak to a PML lawyer about your legal options. Our law firm is dedicated to fighting for the rights of those that have been harmed by dangerous and recalled drugs and medical devices. For over 25 years, Attorney David Willis has been a trial lawyer representing seriously injured clients in product liability and personal injury lawsuits such as defective drug litigation, class action drug lawsuits and medical device recall lawsuits. If Tysabri has harmed you, or a loved one, contact us right now to discuss your potential case in filing a Tysabri PML Lawsuit.

© Willis Law Firm for Drug Attorneys. Replication strictly prohibited without written consent.