Drug extends life of Lou Gehrig patients.

After decades of disappointment, researchers are proclaiming a "first step" toward a remedy for Lou Gehrig's disease. In a recent study of nearly 1,000 people, a promising drug has briefly prolonged the lives of sufferers.

The drug, riluzole, marks the only advance in treatment for victims of Lou Gehrig's disease-known to doctors as amyotrophic lateral sclerosis (ALS)-in the half century since the famed Yankee first baseman died of it.

Researchers caution, however, that the drug is only partially effective and is not an answer to anyone's prayers. Although riluzole extends life, it cannot halt the degenerative nerve disease, repair the nervous system, or even make patients feel better.

"No drug will improve any ALS patient as motor neurons are destroyed. It is impossible at the moment to think about a recovery, whatever drug is used," concedes Vincent Meininger of the Salpetriere Hospital in Paris, a member of an international research team that reported its findings in the May 25 Lancet.

That doesn't mean the drug is valueless, the researchers conclude. "Our experience as clinicians suggests that psychological well-being is enhanced by the availability of a treatment that is safe and well-tolerated and has a proven effect on the disease-in contrast to the many drugs (some of them unsafe) to which thousands of patients have been exposed over the years."

Jeffrey D. Rothstein of Johns Hopkins Medical Institutions in Baltimore says the new study has shown that "the drug can work in ALS, it can work in all patients, and we've figured out which dose is the best dose. This is the first drug we've had that does something reliably in ALS."

In most cases, ALS strikes after age 40. Nerve cells in the brain stem or spine begin to die. Some people first experience a mild weakness in their arms and legs, others difficulty swallowing or speaking. Ultimately, ALS ravages the nerves and muscles, turning the body into a coffin enclosing an intact mind. After diagnosis, patients survive an average of just 2 to 5 years.

Researchers believe the disease results from overstimulation of nerve cells by a chemical messenger called glutamate, which ferries nerve signals across the tiny gulf separating nerve cells. In ALS patients, excess glutamate lingers in the gap, exciting nerve cells to death. Riluzole slows the damage temporarily by blocking the release of glutamate from nerve cells.

In the 18-month study of 956 patients in Europe, Canada, and the United States, riluzole reduced the risk of death by 35 percent. It also diminished the need for a tracheostomy-a procedure in which doctors surgically create an airway into the throat to bypass unresponsive respiratory muscles.

The researchers randomly divided study participants into four groups. One group was given a daily dose of a placebo. The others were given riluzole in daily doses of 50, 100, or 200 milligrams.

Those who received 100-mg doses fared better than the others. For instance, 57 percent of volunteers in the 100-mg group survived 18 months, compared to 50 percent of those in the placebo group. There were no severe side effects.

The Lancet study represents an improvement over an earlier trial involving 155 patients (SN: 3/26/94, p. 202). That study suggested that riluzole worked primarily in people whose ALS began in the brain stem. The recent report says those mixed results were a statistical blip caused by the small number of volunteers.

On the basis of this and other studies, the Food and Drug Administration approved riluzole last year.