Biogen, Elan Get No New Reports Of Brain Infection From Tysabri
WALL STREET JOURNAL
WASHINGTON -- There have been no additional reports of a serious brain infection known as progressive multifocal leukoencephalopathy, or PML, among patients taking the multiple-sclerosis drug Tysabri, the drug's makers said Thursday.
Biogen Idec Inc. and Elan Corp., also said there were no reports of other "serious opportunistic infections," as of April 23. The companies released the first safety update involving Tysabri since the drug was allowed back in the U.S. market last June. The data was released at the American Academy of Neurology's annual meeting on Boston.
The drug was pulled off the U.S. market in February 2005 after two patients developed PML and one died. A third patient was later discovered to have PML and also died.
Tysabri is currently under a restricted distribution system and a program that allows the companies to track potential safety problems with the drug.
The companies said about 12,500 patients world-wide have been prescribed Tysabri, including about 6,600 patients in the U.S. currently who are on therapy.
The companies said about 10,000 U.S. patients and 1,500 physicians have enrolled in the restricted distribution program known as Touch. Tysabri is administered as an infusion in a clinic. The FDA recommends the drug be used only after other treatments fail for the relapsing-remitting form of MS. MS is a progressive disease that involves damage to nerves controlling muscles and vision, and affects about 400,000 Americans.
Before Tysabri can be started, patients must undergo a magnetic resonance imaging or MRI scan to differentiate potential future multiple sclerosis symptoms from PML. Patients would then be evaluated at three months, six months and then every six months after that. The status of those evaluations must be reported by doctors to Biogen Idec.
Biogen and Elan also issued an update on an extension study of an original two-year study that involved 942 patients. That study, known as Affirm, showed Tysabri cut the annual risk of relapse by 67% compared with patients on placebo, or a fake drug. The extension study includes 531 patients, 250 who have received almost three years of therapy.
The companies said, the annualized relapse rate for patients treated with Tysabri over the three-year period was 0.23, which translates into an average relapse rate of one relapse every 4.3 years. Over the three-year treatment period, the relapse rate averaged 0.27 during the first year; 0.20 during the second year; and 0.15 during the third year.[CLICK HERE TO GO TO WALL STREET JOURNAL]
