By Tom Randall
July 31 (Bloomberg) -- Biogen Idec Inc. and Elan Corp. reported two confirmed cases of a deadly brain infection in patients taking the multiple sclerosis drug Tysabri, the first since the drug was reintroduced in the U.S. in 2006.
The report sent shares of both companies tumbling. The two patients were in the European Union, Biogen said today in a regulatory filing. The cases of the disease, progressive multifocal leukoencephalopathy, were confirmed this week, according to the company's statement.
Biogen and Elan voluntarily pulled the drug from the market in February 2005 after three patients unexpectedly contracted the disease, which caused two deaths. Tysabri was reintroduced in July 2006 in the U.S. and sold for the first time in the EU at the same time. One patient had been taking the drug for 17 months and the other took it for 14 months, Biogen said.
``This is going to be fairly disruptive to sales in the United States,'' said Mark J. Schoenebaum, an analyst with Deutsche Bank Securities in New York, by telephone. ``There is a real fear of the unknown here, and I think some patients and physicians are going to take a drug holiday'' until the company discloses more details.
More than 31,800 multiple sclerosis patients use Tysabri, Biogen spokeswoman Naomi Aoki said. About 14,000 patients have taken Tysabri for more than a year, and 6,500 patients have taken it for 18 months or longer.
Anticipated Cases
``We've said ever since the reintroduction that we anticipate seeing additional cases,'' Aoki said today in a telephone interview. ``Withdrawing the drug is not under consideration.''
The condition was included in the prescribing information on the drug as a possible side effect in 1 of every 1,000 patients taking the drug, Aoki said. One patient is clinically stable and is at home, Biogen said. The other patient is hospitalized.
The shares of Biogen, which is based in Cambridge, Massachusetts, fell by $14.06, or 20 percent, to $55.60 at 7:20 p.m. New York time, after the close of regular trading on the Nasdaq Stock Market. American depositary receipts of Elan, which is based in Dublin, fell by $7.98, or 39 percent, to $12.07. Each receipt equals one ordinary share.
``We expect the stock to open sharply down on Friday, but would not be buyers as we think investor sentiment could continue to weaken,'' Schoenebaum said in a note.
Goal of 100,000 Patients
On July 22, Biogen reported second-quarter net income rose 11 percent to $207 million on sales of Tysabri, its fastest- growing treatment. Biogen has estimated 100,000 patients will be taking Tysabri by 2010, a goal critical to the company's future growth, Thomas Weisel analyst Ian Somaiya said in a note to clients at the time.
Tysabri was approved in the U.S. in January to treat Crohn's disease, an inflammatory intestine and bowel disorder.
Shares of Elan, Ireland's biggest drugmaker, already were battered this week after Wyeth and Elan's experimental treatment for Alzheimer's disease, bapineuzumab, was linked in a study to a brain-swelling side effect.
To contact the reporters on this story: Tom Randall in New York at trandall6@bloomberg.net
Last Updated: July 31, 2008 19:29 EDT
