A trial drug, a derivative of an older medicine, has been found to work well on older people who have difficulty sleeping, according to researchers. In addition to creating more sleep at night, the pill led to healthier, sounder sleep at night and also helped cut down napping during the day.

The drug, which has not yet been approved by the U.S. Food and Drug Administration, is eszopiclone, a derivative of zoplicone. Dr. W. Vaughn McCall, chairman of psychiatry and behavioral medicine at Wake Forest University Baptist Medical Center, discussed results of the research at the American Psychiatric Association annual meeting last week.

About 300 seniors were observed during a two-week trial period with the drug. Those who took the drug were awake only 63 minutes during the night, compared with 75 minutes for a group that took a placebo. Sleep time for the test group was about 375 minutes nightly, com pared with just 350 minutes for the placebo group, McCall added. Napping days were cut by one-third in the group taking the drug, he said.

The test drug is similar to two sleeping pills currently on the market, McCall said: Sonata (zaleplon) and Ambien (zolpidem). The study was paid for Sepracor Inc., which makes eszopiclone.