The Associated Press
Published: August 1, 2008
NEW YORK: Biogen Idec Inc. and Elan Corp. defended their multiple sclerosis drug Tysabri on Friday after reporting two new cases of a potentially fatal side effect, saying the treatment is still worth the risk to patients.
There are no plans to pull the drug off the market, and the company said its current monitoring program for cases of a rare but sometimes fatal brain disorder is adequate.
The announcement of two new cases of the rare viral infection called progressive multifocal leukoencephalopathy, or PML, sent shares for both companies plummeting and reignited already simmering concerns about the drug's sales potential. It was pulled from the market in 2005 after being linked to the rare brain disease but was reintroduced under restricted sales conditions in mid-2006.
"These cases underscore the importance of continued clinical vigilance so PML can be discovered and managed appropriately," said Dr. Cecil B. Pickett, president of research and development at Biogen.
He and several other executives tried to allay concerns over additional cases during a conference call with financial investors and analysts Friday morning. The company said it would also hold calls with several physician and patient groups.
The risks associated with the drug are clearly labeled, the company said, and all patients are not only notified but have to sign a waiver acknowledging the risks. PML almost always occurs in people with a severe immune deficiency, as is the case with most patients taking Tysabri.
Multiple sclerosis is an autoimmune disorder that results in physical and neurological damage.
There are about 32,000 patients on Tysabri worldwide, with 17,800 in the U.S., the company said. It would not comment on its financial outlook, but did say future cases of Tysabri were anticipated and factored into the goal of eventually getting the drug to 100,000 patients worldwide.
The companies maintain the drug still has a favorable risk-reward profile, meaning it is more helpful than hurtful, and monitoring programs are set up in the U.S. and Europe to catch any potential cases of PML early. Those systems rely on physicians to test for the condition if they start to see symptoms. Biogen and Elan would not comment the number of suspected cases, only confirmed cases.
Both new cases came out of European, with the first patient having been on Tysabri for 17 months. Another, who is still hospitalized, had been on Tysabri for 14 months. Still, the company said it can count about 6,600 patients on the drug for about 18 months now, reinforcing its stance that the treatment is worth the risk.
Food and Drug Administration officials could not immediately be reached for comment as of Friday morning.
The broader market, meanwhile, remains concerned over the impact on sales, which nearly tripled to $200 million during the second-quarter. The treatments costs about $30,000 per year.
"We do not believe that Tysabri will be withdrawn, based on this data, but it is likely to spook investors as the true rate of PML in Tysabri monotherapy is unknown," Goldman Sachs analyst Stephen McGarry said in a note to Elan investors.
Shares of Cambridge, Massachusetts-based Biogen fell to $50.28, their lowest point in more than a year, while shares of Ireland-based Elan fell to $10.67, their lowest point in nearly three years.
