Biogen Idec gets OK to resume sale of MS drug
The Food and Drug Administration yesterday gave Biogen Idec Inc. the go-ahead to resume sales of the multiple sclerosis drug Tysabri, which was pulled from the market 16 months ago after the discovery of an unexpected rare brain disease that killed two patients.
But the many MS patients who have waited anxiously for the drug's return because of its powerful ability to retard debilitating flare-ups must wait a while longer. To try to catch any early signs of the rare brain disease, the FDA and the Cambridge biotechnology giant agreed on a comprehensive safety plan under which doctors and other health professionals must undergo additional training before they administer Tysabri.
Company officials said that while some doctors may be able to administer Tysabri by the end of this month, it could be several more months before most of the roughly 2,000 medical offices that previously administered Tysabri are ready to restart. Unlike most other MS drugs, which are given in weekly or more frequent injections, Tysabri is given in a once-a-month intravenous infusion.
``First we have to educate everybody," said James C. Mullen , Biogen's chief executive. ``We have to help people through what is a little bit of an onerous and cumbersome process."
Mullen urged MS patients to continue treatment with other drugs while they wait for Tysabri to come back.
Art Mellor , chief executive of the Accelerated Cure Project in Waltham, a nonprofit organization devoted to curing MS, said, ``It's great to have another choice for people with MS, especially one that had results this good in terms of modifying the disease. I spoke to a few people who were on it when it was available and were doing better, and they're dying to get back on it."
When Tysabri was first approved in 2004, it was considered a breakthrough. In clinical trials, the drug proved twice as effective as other treatments in preventing relapses. It was reviewed and approved by the FDA after only one year of a planned two-year trial.
MS is a degenerative disease in which the body's immune system attacks the insulating sheath on nerves in the brain and spinal cord, leading to a wide array of progressively worse symptoms, including numbness, difficulty balancing and walking, impaired vision, and others. About 500,000 patients have the disease nationwide , and most have a form characterized by periods of relative health interrupted by debilitating flare-ups.
Tysabri is coming back, however, with restrictions. At a hearing in March, a panel of experts advising the FDA recommended Tysabri could be used as a frontline medication. That means it could be used as the first treatment given to patients after they are diagnosed with MS. But yesterday the agency, which doesn't have to follow the panel's recommendations, was not as clear-cut.
In the prescribing information released yesterday, the FDA said Tysabri ``is generally recommended for patients who have had an inadequate response to, or are unable to tolerate, alternate multiple sclerosis therapies." That wording makes it likely Tysabri will be a second-line treatment, but the FDA has left the door open for doctors to prescribe it as a frontline drug.
Investors expecting a clearer decision from the FDA were disappointed. So on a day when broad stock market indexes declined sharply, shares of Biogen Idec and its partner in Tysabri, Elan Corp. of Ireland, fell harder still. Biogen Idec closed down $2.32 to $45.39, a drop of nearly 5 percent. Elan shares shed $2.46, or almost 13 percent, to close at $16.52.
Elise Wang , a Smith Barney analyst, called Wall Street's moves an ``overreaction," saying the FDA's decision was largely a victory for both companies.
Dr. Burt Adelman , Biogen Idec's executive vice president of development, said investors may also have been reacting to the detailed safety instructions released yesterday.
Access to Tysabri will be tightly controlled. Patients will be counseled on the risks of getting progressive multifocal leukoencephalopathy, or PML, a rare opportunistic brain infection that can lead to quick death. Patients will have to sign a consent form acknowledging the risks and will also be evaluated for possible signs of PML after the first three months and every six months thereafter.
``If that's what the Street is responding to, it's disappointing," he said. ``It probably is. But they'll get over it as we execute on our plan to train doctors" and other healthcare professionals.
In early 2005, just three months after Tysabri was initially approved by the FDA, Biogen Idec and Elan pulled the drug off the market, saying they had found a patient in a trial with PML. After an extensive review, the companies found that three people in clinical trials had contracted the disease, and two died. None of the patients who took the drug when it was on the market contracted the disease.
Two of the patients who contracted the disease were also treated with Avonex, another drug for MS made by Biogen Idec. That suggested that the two drugs together increased the risk of contracting PML. In the new label, Tysabri can only be used on its own, without any other treatments.
Tysabri is one of only a handful of drugs that have returned to the market after they were withdrawn for safety reasons. At the time the drug was withdrawn, some analysts said the drug would never return, or might only be a niche product with $300 million in annual sales.
Jennifer Chao , an analyst at Deutsche Bank Securities, predicted the drug would reach $325 million in sales next year, and would peak around 2011 with annual sales of between $2 billion and $3 billion.
``The Street all but thought Tysabri was dead upon news of the first cases of PML," said Chao. ``This new sales profile exceeds our initial recommendations upon the withdrawal of the drug."
Jeffrey Krasner can be reached at krasner@globe.com. 
