CAMBRIDGE, Mass. (AP) — Biogen Idec Inc. said Tuesday sales of its multiple sclerosis drug Tysabri topped $1 billion in 2009, and there were 30 percent more new patients taking the drug.
The growth comes as the rate of a potentially fatal side effect in patients taking Tysabri remains a lingering concern for Wall Street. In 2005, the drug was pulled from the market because of concerns over a potentially fatal brain infection called progressive multifocal leukoencephalopathy, or PML.
Sales resumed in July 2006 with restrictions, though about two dozen cases have since been reported, mainly abroad.
In 2009, sales reached $1.06 billion, with $508.5 million in the U.S. and $550.7 million internationally.
A key concern has been that fears of the brain infection could bog down the addition of new patients. At the end of 2009, there were 48,800 patients taking Tysabri worldwide, including 24,500 in the U.S. and 23,700 internationally. An additional 600 patients were taking the drug in clinical trials.
Several analysts said the rate of new patients adding the drug is slowing.
Leerink Swann analyst Dr. Joshua Schimmer said about 2,600 started taking the drug during the fourth quarter, down from more than 2,900 in the third quarter. But he said much of the concern is already included in outlooks for the company.
He reaffirmed an “Outperform” rating on the stock and said Tysabri revenue is in line with Wall Street expectations.
Looking ahead, the company has said it will focus on accelerating growth of Tysabri and its top seller, the multiple sclerosis drug Avonex.
Shares of Biogen fell 65 cents to close at $53.25.