Thursday, 16 March 2006 00:00

A Statin Improves Performance of Multiple Sclerosis Drug

THURSDAY, March 16 (HealthDay News) -- The same researchers who showed that a cholesterol-lowering statin drug might prevent development of full-blown multiple sclerosis are now reporting that statin therapy might improve the performance of existing MS drugs.

The first discovery led to a nationwide study in which people who have the initial symptoms of the autoimmune nerve-damaging disease are taking a statin in hopes of avoiding MS.

"What we have shown now is that we have data in an animal model, that when this statin is used in combination with Copaxone, it may augment the activity of Copaxone," said study co-author Dr. Scott Zamvil, associate professor of neurology at the University of California, San Francisco. "That is provocative data supporting human testing of this combination."

While the research has so far been limited to lab mice, the scientists hope the findings might one day lead to improved treatments for people with the disease. The findings appear in the March 16 online edition of the Journal of Clinical Investigation.

Combination therapy is desirable because Copaxone, like other MS drugs, is effective in only 30 percent to 35 percent of cases of the most common form of the disease, Zamvil said. In one animal study, adding high doses of atorvastatin (Lipitor) dramatically reduced central nervous system inflammation and seemed to eliminate the paralysis caused by a model disease that closely resembles MS. In contrast, there was no reversal of the disease in animals that received low doses of Lipitor or Copaxone.

In multiple sclerosis, immune cells attack a layer of insulation known as myelin that surrounds nerve fibers in the brain and spinal cord. Copaxone is one of a family of drugs that suppresses the activity of the chemicals that destroy myelin.

Lipitor also appears to act against the destructive immune system activity, but through a different mechanism, Zamvil said. "They can have an additive effect," he said, referring to the combination of Lipitor and Copaxone. "We were able to see a clinical and immunological benefit."

The reults do not necessarily apply to all statin drugs, he said. "They all act on the same enzyme to reduce cholesterol but they differ in their ability to cause immune modulation," Zamvil said. Data from unpublished studies indicate that Lipitor has more immune system activity, he said.

Zamvil said he's aware that some people with MS are already taking a statin, but he advised against it at this point to combat the disease. "We don't know if it is effective or not at this stage," he said. "Even though they [statins] are relatively safe, we are speaking of higher doses."

That caution was echoed by Dr. Jeffrey Cohen, a neurologist at the Cleveland Clinic, one of 14 U.S. centers involved in a trial of statin therapy to prevent MS in people who have had a first neurological event that often leads to the disease. The trial has been going on for a year, and five people have been enrolled at the Cleveland Clinic, he said, adding that results of the trial might start to emerge in a year or two.

"There is a lot of interest in statins and they are generally well tolerated, but we are cautioning people not to rely on statins for multiple sclerosis treatment," Cohen said. "The doses are on the high side, so there is some potential for side effects and toxicity."

Inevitably, some people treated for MS at the Cleveland Clinic are taking a statin because they have high cholesterol, Cohen said. "It doesn't appear to have an adverse effect on MS, and at this point it is hard to determine whether it is helpful for MS," he said.

More information

For more information, visit the National Multiple Sclerosis Society.p