Information provided by a Tysabri patient (Karen M) in Miami who has no fears
By Thomas Gryta, Of DOW JONES NEWSWIRES
NEW YORK -(Dow Jones)- Biogen Idec Inc. (BIIB) disclosed four more cases of a rare brain infection in multiple sclerosis patients on Tysabri, which it sells with Elan Corp. (ELN), bringing the total number of cases to 46 as of April 6.
The Cambridge, Mass., biotech company also reported two additional deaths in patients that have developed progressive multifocal leukoencephalopathy, or PML, bringing the total to 11.
Tysabri is considered a highly effective therapy for MS, and its growth is important to the future of both Elan and Biogen. But its sales have been slower than originally hoped amid concerns about the risk of PML that led to its 18- month market withdrawal beginning in 2005.
"The overall global rate generally falls within the 1-in-1,000 rate previously seen in clinical trials," Biogen spokeswoman Naomi Aoki said. That rate is what is implied on the drug's label.
Shares of Biogen recently traded down 1.2% to $54.33, while Elan's American depositary shares dropped 3.6% to $7.78. Biogen is scheduled to report first- quarter results Tuesday and Elan will do the same Wednesday.
Of the new cases, 17 were in the U.S., 26 were in the European Union and three were in other areas.
Biogen provides monthly updates on the number of PML cases, giving its last update in mid-March.
A patient's risk of getting PML increases with the number of monthly infusions that he or she receives, something that the Food and Drug Administration highlighted in a January safety update. The agency concluded that the benefits of the medicine continue to outweigh the risks.
The most recent update translates to about 1.33 cases per 1,000 patients on the drug for between two and three years. That figure has dropped for the past two months, coming in at 1.36 in mid-March and at 1.56 in mid-February.
The incidence is about 0.33 case per 1,000 patients in those using it for one to two years, and it is almost nonexistent in patients using less than a year.
The number of cases is important because if the infection rate climbs too high, sales of the drug may drop.
For patients on the drug for a year or longer, the rate is 1.1 cases per 1, 000, but rises to 1.53 per 1,000 for those on the drug for two years or longer.
Tysabri's withdrawal from the market occurred after three patients developed PML. The infection re-emerged in mid-2008, and Biogen provided regular updates about the cases until mid-2009. The company began providing monthly updates in mid-February.
-By Thomas Gryta, Dow Jones Newswires; 212-416-2169; thomas.gryta@dowjones.com
(END) Dow Jones Newswires 04-15-101604ET Copyright (c) 2010 Dow Jones & Company, Inc.
0 comments:
Post a Comment