1 Aug 2008 08:40
On July 31, 2008, Biogen Idec Inc. and Elan Corporation, plc notified relevant regulatory agencies of two confirmed cases of progressive multifocal leukoencephalopathy (PML) in multiple sclerosis (MS) patients treated with TYSABRI® in the commercial setting. Additional information about these cases is set forth below.
Case 1
On July 30, 2008, following a period of clinical evaluation, Biogen Idec received confirmation of a diagnosis of PML in an MS patient in the European Union (EU).
The diagnosis was made based upon the detection of JC Virus (JCV) DNA in the cerebrospinal fluid (CSF) in the setting of clinical signs, symptoms and magnetic resonance imaging (MRI) findings consistent with the diagnosis of PML.
As reported to the company on July 31, 2008, the patient remains clinically stable and ambulatory at home.
Background:
Patient in EU with aggressive MS who was naïve to prior disease modifying therapy;
TYSABRI monotherapy for approximately 17 months;
Clinical vigilance led to early identification of signs and symptoms of possible PML and medical work-up which included MRI scanning and CSF testing, but PML was not confirmed at that time;
However, given continued clinical suspicion by treating physician, plasma exchange was initiated as outpatient;
Subsequent testing of CSF detected JCV DNA, which was reported to the company on July 30, 2008;
It was then determined by PML experts that the latest CSF results, together with the clinical history, physical findings, and MRI results, are consistent with the diagnosis of PML.
Case 2
On July 31, 2008, Biogen Idec was notified of a diagnosis of PML in a second MS patient in the EU.
The diagnosis was made based upon the detection of JCV DNA in the CSF in the setting of clinical signs, symptoms, and MRI findings consistent with the diagnosis of PML.
As reported to the company on July 31, 2008, the patient is currently hospitalized.
Background:
Patient in EU with MS with a history of prior disease modifying therapies including azathioprine and beta-interferons;
TYSABRI monotherapy for approximately 14 months;
Evaluation for possible PML, included MRI scanning and CSF testing;
CSF testing detected JCV DNA, which was reported to the company on July 31, 2008;
The CSF results, together with the clinical history, physical findings, and MRI results, are consistent with the diagnosis of PML.
This announcement has been issued through the Companies Announcement Service of
The Irish Stock Exchange