WASHINGTON (Reuters) - An insomnia drug that helps the body produce more of the sleep hormone melatonin may improve sleep for jet-lagged travelers and shift workers, researchers reported on Monday.
Maryland-based Vanda Pharmaceuticals Inc. reported on two studies of its drug tasimelteon, also known as VEC-162, that showed it helped patients sleep longer and more deeply than a placebo.
They said that people with so-called circadian rhythm disorders could be helped. These disorders are common causes of insomnia that affect millions of people whose activities are out of sync with their internal body clocks.
These disorders entail persistent sleep disturbances, insomnia when trying to sleep and excessive sleepiness while trying to remain awake, the researchers said.
"...Tasimelteon has the potential for the treatment of patients with transient insomnia associated with circadian rhythm sleep disorders, including people affected by jet lag, or those who work at night, and early-riser workers," they wrote in their report, published in the Lancet medical journal.
Dr. Shantha Rajaratnam of Brigham and Women's Hospital and Harvard Medical School in Boston and colleagues, working with the company, did both Phase II and Phase III trials of the drug, aiming to show it is safe and works.
Volunteers slept in labs and were tested using devices known as polysomnographs, which measure sleep activity.
Patients given tasimelteon fell asleep faster, had better sleep and woke up faster, they reported. The drug did not cause any more side-effects than a placebo, they noted.
Melatonin can fight jet lag too but over-the-counter melatonin products are not regulated, they pointed out, and have not been consistently shown to help treat jet lag and other sleep disorders.
The market is potentially large. The study quoted U.S. labor statistics as finding that about 20 percent of the workforce or about 19.7 million U.S. workers are early risers who start work between 2:30 a.m. and 7 a.m.
"Most of these people probably experience chronic sleep restriction because they are unable to initiate and maintain sleep when they attempt to sleep in the early or late evening hours. Tasimelteon might alleviate this problem by advancing the sleep-wake cycle, by providing a direct sleep-promoting effect, or both," they wrote.
In a commentary, Dr. Daniel Cardinali of the University of Buenos Aires and Dr Diego Golombek, National University of Quilmes in Argentina, noted that drugs such as valium can be addictive.
"Shift-workers, airline crew, tourists, football teams, and many others will welcome the results of Shantha Rajaratnam and colleagues' study in The Lancet today," they wrote.
Reporting by Maggie Fox; Editing by Cynthia Osterman