Tysabri, a drug used to treat multiple sclerosis, has been linked to another case of progressive multifocal leukoencephalopathy, or PML. According to a report on Reuters.com, this latest case of Tysabri-associated PML was confirmed on June 10.
Tysabri is now available only to patients with relapsing multiple sclerosis (MS) or Crohn’s disease (CD) who are enrolled in the risk minimization plan called the TOUCH Prescribing Program. Under the TOUCH Prescribing Program, every Tysabri-treated patient is closely monitored and followed for the occurrence of PML and other serious opportunistic infections.
According to The Wall Street Journal, Biogen Idec has been posting a PML case update on the Internet every Friday. That will continue until July 24 - the third anniversary of the drug’s relaunch - by which time it expects the risk/benefit profile of Tysabri to be clearer. This is the eighth case of Tysabri-associated PML reported by Biogen Idec in the past year. Of those cases, one has been fatal.
Like all but two of those PML cases, this latest occurred in a patient overseas, the Journal said. Biogen Idec said this latest patient took 35 doses of the monthly medication, the most of any of the post-launch cases. According to The Wall Street Journal, some believe that duration of Tysabri therapy plays a role in the drug’s PML risk.
Last August, Biogen Idec announced that Tysabri had been associated with two other European cases of PML. One patient had been taking Tysabri for 14 months and the other for 17. But unlike others stricken with PML, those patients had been taking Tysabri as monotherapy - with no other drugs. It had been theorized that patients contracting PML had done so because of exposure to multiple medications and that monotherapy with Tysabri was less risky. ...complete story in NEWS Inferno.com