Test Predicts Which Patients Benefit From $6 Billion MS Drugs
March 28, 2010, 2:56 PM EDT
March 28 (Bloomberg) -- Multiple sclerosis drugs from Biogen Idec Inc., Merck KGaA and Bayer AG with sales of $6.1 billion work for fewer than 3 in 4 patients and a test can predict which ones, a study found.
Researchers at Stanford University analyzed mice with an induced disorder similar to MS and blood samples saved from humans with the disease. They found two different subtypes of disease, each driven by excess activity of a different set of infection-fighting immune cells. Only the patients with one sub- type responded to the MS drugs known as beta interferons.
In MS, the body attacks itself, damaging the insulation that protects nerve cells and disrupting their ability to transmit electrical impulses and move muscles. About 2.5 million people worldwide have the disease. The study, published today in the journal Nature, reveals why beta interferons, widely used drugs that suppress immune-system activity, don’t work for everyone.
“A lot of people are taking beta interferons who should not be and it may make them actually worse,” Lawrence Steinman, a neurology professor at Stanford University near Palo Alto, California, said in a March 25 telephone interview. “We found a simple test in the blood that predicts who will and will not respond to beta-interferon.”
The test measures blood levels of IL1 and of IL17, the two immune cells Steinman and his colleagues linked to different forms of the disease. Patients whose disease is driven by IL1 respond to beta interferon drugs while patients with IL17-linked disease don’t, Steinman said.
Likely Responders
“This information could allow us to better select a group of people who are likely to respond in the first place and to optimize use of the drug,” said Dean Wingerchuk, a professor of neurology and vice-chair of research at the Mayo Clinic in Scottsdale, Arizona. “It’s the first step toward identification of objective biomarkers that would lead to the goal of personalized therapy.”
The leading beta interferons on the market are Avonex from Cambridge, Massachusetts-based Biogen with 2009 sales of $2.3 billion; Rebif, from Merck KGaA, based in Darmstadt, Germany, with $2.1 billion in sales and Betaferon, by Bayer AG of Leverkusen, Germany, which had $1.7 billion in sales in 2008, the last year for which revenue figures were available.
Biogen markets the MS drug Tysabri with Dublin-based Elan Corp. and sells Fampridine-SR, made by Hawthorne, New York-based Acorda Therapeutics Inc., outside the U.S. Biogen strives to offer a range of options for multiple sclerosis patients, said spokeswoman Naomi Aoki, in a March 24 telephone interview.
‘Personalized Approach’
“We’re excited about the prospect of taking a more personalized approach to identifying patients who are most likely to respond to different therapies, including beta interferons,” Aoki said.
A test that identifies likely non-responders to beta interferon drugs may boost prescribing for the leading MS drug, Teva Pharmaceuticals Industries Ltd.’s Copaxone, said Denise Bradley, a company spokeswoman, in a March 24 e-mail. Copaxone had sales of $2.4 billion in 2009. Petah Tikva, Israel-based Teva is working to develop tests that predict patients who will respond to Copaxone, she said.
Beta interferons are genetically engineered copies of naturally occurring proteins approved for patients whose MS doesn’t keep them from walking, according to the Mayo Clinic Web site. While the medications can slow progression of the disease, they don’t reverse existing damage and haven’t been shown to prevent disability, Wingerchuk said.
While doctors may use the blood tests to guide prescribing, more study is needed to validate the findings before they become part of routine practice, said Steinman, the study author. Further research also will be needed before regulators allow drugmakers to recommend the test in prescribing information, he said.
Still, Steinman said, “the test is likely to become a standard. It looks like a biological truth.”
--Editors: Andrew Pollack, Angela Zimm
To contact the reporter on this story: Rob Waters in San Francisco at rwaters5@bloomberg.net.
To contact the editor responsible for this story: Reg Gale at rgale5@bloomberg.net. |
