Researchers Report Success Using Medicines for Cancer, Asthma
By Jon Hamilton, MS WebMD Medical News
Oct. 12, 1999 (Seattle) -- Drugs used to fight asthma and cancer appear to work against multiple sclerosis as well, researchers reported Tuesday at the 124th annual meeting of the American Neurological Association.
Experts say the results are preliminary, but offer new hope to patients with the disabling condition. "This is very encouraging because right now doctors have very little to offer patients with this disease," Mario Moscarello, PhD, a researcher at the Hospital for Sick Children in Toronto, tells WebMD.
Multiple sclerosis, or MS, is a potentially fatal disorder that affects nerve fibers, gradually causing problems including weakness, numbness, and difficulty performing mental tasks. Researchers believe MS occurs when the immune system mistakenly attacks the protective sheath that surrounds nerves. There is no cure for MS and only a few drugs have been shown to slow its progression.
In two studies presented at the meeting, researchers reported that a cancer drug called paclitaxel could stop MS -- or even reverse its course. Moscarello says that in mice that develop MS, paclitaxel was able to delay the onset of symptoms. Even more encouraging, he says, is the fact that that were mice given injections of the drug were found to have high levels of a substance indicating that their bodies were repairing damage to the protective outer layer of the nerves.
"This is the first time we've seen this with any drug," says Moscarello. He says existing drugs tend to make people with MS feel better, but do not stop the disease.
Another team from Canada reported that paclitaxel seems to work in humans with MS. Researchers from the University of Toronto said they gave monthly injections of the drug to 30 people with a late stage of the disease. The dose was about one-fourth the amount usually given to cancer patients.
Paul O'Connor, MD, chief of the university's MS clinic, tells WebMD that the treatment produced encouraging results on standard tests used to assess the progress of the disease. "People who got the drug stabilized or even got better, especially at the higher dose," he says.
O'Connor says paclitaxel seems to work by preventing the immune system from becoming overactive and attacking the body's own healthy tissues.
Researchers from Japan offered another approach to treating MS -- using drugs that are often used for asthma. A team from Nara Medical University in Kashihara gave 16 patients a combination of three drugs known as phosphodiesterase inhibitors, or PDEIs.
The researchers measured the number of relapses the patients had each year. Relapses, which are periods during which symptoms become much worse, are usually followed by remissions, or periods in which symptoms decrease.
Before treatment, patients averaged more than three relapses each year. But after a year of treatment, the number fell to about one relapse per year, the team reported.