NEW YORK (Reuters Health) - Promising new research in mice suggests that the arthritis drug celecoxib (Celebrex) might delay the onset of symptoms of amyotrophic lateral sclerosis (ALS), commonly known as Lou Gehrig's disease.

The drug prolonged survival of the mice by 28 days, or 25% of their life span, although study results in mice are not necessarily applicable to humans. More study is needed to determine if the drug may help patients with ALS, a progressive neurological disease resulting in muscle weakness and eventual paralysis. The disease, named after baseball player Lou Gehrig, affects approximately 1 in 100,000 people

A multi-center clinical trial testing the drug on about 350 human patients with ALS is currently under way. Results are expected within one to two years, according to Dr. Jeffrey Rothstein, a neurologist at the Johns Hopkins University School of Medicine in Baltimore, Maryland.

"Every time we discover a drug that has therapeutic potential in our models and that can be readily used in humans, it is important," Rothstein told Reuters Health. Celebrex is already on the market and does not have to go through lengthy FDA testing and approval.

Riluzole is the only FDA-approved drug for ALS, but does not work that well, according to Rothstein.

Celebrex is a COX-2 inhibitor, a class of drugs used to treat arthritis because they block an inflammation-promoting enzyme. The enzyme may play a role in ALS by stimulating astrocytes, star-shaped cells that surround neurons in the brain, to release excessive amounts of chemical communicators in the brain.

If too many are released, it can be toxic to cells, a condition that is "implicated in ALS. It is not necessarily a cause of the disease but it is a propagating factor that keeps the disease going," said Rothstein.

In the study, the researchers used mice genetically engineered to produce a human gene linked to ALS. The mice, which have a shorter-than-normal life span of 4 months, were fed chow laced with high doses of celecoxib. Symptoms such as motor decline and weight loss appeared about 2 weeks later in the mice fed celecoxib compared with mice not fed the drug, and they lived about one month longer.

Rothstein said he was "hopeful" that it would have an effect in humans, just as it did in the rodent counterpart.

He cautions though that the doses of Celebrex being used in the study are far larger than the dose prescribed to relieve the inflammation from arthritis.

The study was funded in part by grants from the National Institutes of Health, the Muscular Dystrophy Association and Pharmacia, the manufacturer of celecoxib.

SOURCE: Annals of Neurology 2002;52.

Copyright 2002 Reuters News Service.