09.13.06, 12:00 AM ET
WEDNESDAY, Sept. 13 (HealthDay News) -- Swiss researchers report that an oral drug called fingolimod was effective in preventing relapses in people with multiple sclerosis.
"If the phase III [clinical trial] is successful, a new once-daily oral medication could be available for treatment of relapsing MS in approximately three to four years," said lead researcher Dr. Ludwig Kappos, head of the outpatient clinic for neurology/neurosurgery and MS-Research Group at University Hospital in Basel.
Results of the phase II trial are published in the Sept. 14 issue of the New England Journal of Medicine.
However, Kappos, as well as authors of an accompanying editorial in the journal, cautioned that this study was small and short-term. Long-term side effects are unknown, and as with other drugs used to treat MS that suppress immune system activity, could potentially be serious.
"These are very exciting preliminary findings of an experimental drug," said Dr. Patricia O'Looney, director of biomedical research programs at the National Multiple Sclerosis Society. "It's not a cure, but the results were very dramatic. The relapse rate was reduced by almost 50 percent in both treatment groups. But, there were some side effects: some upper respiratory tract infections, elevated liver enzymes, and there was some concern about heart rate changes. That's the reason why longer-term studies are necessary."
Multiple sclerosis is a disease that affects the central nervous system, especially the fatty tissue -- called myelin -- that surrounds nerve cells. The disorder is thought to be an autoimmune disease, but its exact cause remains unknown. About 400,000 Americans have multiple sclerosis, according to the National Multiple Sclerosis Society. Many people with the disease have periods where symptoms disappear, followed by relapses or flare-ups.
Treatments are currently available to help keep symptoms at bay, but there is no cure for this disease. The most recently approved drug for MS treatment, available by infusion, is Tysabri (natalizumab). The drug was approved in November 2004, but then pulled off the market three months later because several patients developed a rare, but fatal brain infection known as progressive multifocal leukoencephalopathy (PML). In June 2006, the U.S. Food and Drug Administration allowed Tysabri to return to the market -- under strict prescribing guidelines -- because for some people, the benefits of the medication outweigh the potential risk.
No cases of PML were reported in the six-month trial of oral fingolimod.
Two hundred and fifty-five patients participated in the new trial. They were randomly assigned into one of three groups. One group took a placebo daily, while the other two groups took oral fingolimod in either a 1.25 milligram dose or a 5 milligram dose.
Using MRI scans to assess disease activity, the researchers found that the relapse rate was more than 50 percent lower for both groups taking fingolimod compared to the placebo group, according to Kappos.
Both groups on fingolimod experienced more side effects than those on a placebo, and the group taking the higher dose experienced more adverse effects than those on the lower dose, according to the study. The most frequent complaints were shortness of breath, upper respiratory infections, headache and gastrointestinal problems.
In an accompanying editorial, Harvard researchers wrote, "The results of the current proof-of-concept study by Kappos et al, are certainly promising and should provide a strong incentive for long-term follow-up trials on a large scale."
"The results from this short-term study are very promising and fingolimod needs to be further examined," said O'Looney. "The best news for people with MS is that there are so many clinical trials that are taking place now to try to find better therapies, and some, like fingolimod, are oral therapies. Hopefully, some of these therapies will reduce disease activity even greater than currently approved therapies."