New Sleep Drug Works in Early Studies

Drug, Called Suvorexant, Helped People Fall Asleep Faster, Stay Asleep Longer

From the WebMD Archives

June 13, 2012 -- A new sleeping pill under study helps insomniacs fall asleep faster and stay asleep longer, according to new research.

The medicine, called suvorexant, is not available -- it has not yet been submitted to the FDA. Suvorexant works differently than other sleeping pills, says researcher Andrew D. Krystal, MD, a psychiatry professor at Duke University Medical Center. He reported the findings in Boston this week at Sleep 2012, the annual meeting of the Associated Professional Sleep Societies.

Suvorexant blocks chemical messengers in the brain known as orexins.

"The orexin system seems to be one of the most important, if not the most important, systems for inducing wakefulness,'' Krystal tells WebMD. "It seems to be the system that allows us to remain awake during the course of the day in a continuous chunk. We would fall asleep if it were not for the fact that orexin is being released in increasing amounts during the day."

Suvorexant's development is based on the relatively new idea that people with insomnia have too much activity in their orexin system when they are trying to go to sleep, says Krystal.

By decreasing the orexin activity, "you enhance sleep," says Krystal, who directs Duke's sleep research and insomnia programs.

Suvorexant has been through its phase III clinical trials, which gauge effectiveness and monitor side effects. In those trials, Krystal found the drug could shave off about half an hour of the time it took to fall asleep and add an hour, or more, of sleep time.

The development of almorexant, another drug that targets orexins, was dropped last year by GlaxoSmithKline and Actelion Ltd. for "tolerability" reasons, according to GlaxoSmithKline. Details on those tolerability issues have not been made public.

About Insomnia and Its Treatments

Insomnia affects about 30% of adults in a given year, according to the American Academy of Sleep Medicine. Up to 15% say they have chronic insomnia.

Insomniacs have trouble falling asleep, staying asleep, or both.

Sleeping pills are widely prescribed. In 2011, 63 million prescriptions for hypnotics (such as sleeping pills) and sedatives were dispensed in the U.S., according to the IMS Institute for Healthcare Informatics.

Other sleeping pills work in a variety of ways, such as binding with receptors in the brain that help control alertness or relaxation, or receptors that act on the body's body clock. Of course, there are plenty of other aspects to getting better sleep. Good sleep habits are a must. That includes going to bed at the same time each night, limiting caffeine, keeping TVs, computers, and smartphones out of the bedroom, and getting exercise (but not close to bedtime).