August 3, 2005

Study Shows Drug Cuts Overnight Shift Fatigue

BOSTON -- A drug that treats the uncontrollable sleepiness of narcolepsy can also help the 300,000 to 600,000 Americans who face chronic fatigue and sleep problems from working overnight shifts, according to a study released on Wednesday.

Cephalon Inc.'s modafinil, sold under the brand Provigil, produced fewer lapses in attention and 25 percent fewer reports of accidents or near-accidents on the commute home, according to the study published in the New England Journal of Medicine.

Cephalon paid for the testing, conducted at 28 U.S. medical centers. Modafinil "gets patients about one-third of the way toward normalcy, "said the study's chief author, Charles Czeisler of Brigham and Women's Hospital. "The cautionary note is that they are still quite sleepy. It doesn't immediately eliminate the symptoms of (shift-work sleep) disorder, but it is a clinically significant improvement."

Shift-work sleep disorder is caused by a misalignment of the body's natural sleep rhythms. It becomes severe in 5 percent to 10 percent of workers who are on the job after midnight, making it difficult for them to sleep during the day and stay awake during work.

The disorder increases the risk of accidents and people with the disorder are more likely to suffer from depression, heart disease and ulcers.

While healthy, well-rested people take 10 to 20 minutes to fall asleep, people who doze off in 5 minutes or less are considered pathologically sleepy.

Before they were treated, the shift workers in Czeisler's research fell asleep in about 2 minutes. After taking the drug, that time grew to 3.8 minutes. A placebo produced virtually no change.

Overall, 74 percent of the 96 volunteers who got modafinil were less likely to be excessively sleepy during their overnight shifts, compared to 36 percent of the 108 who got a placebo.

The drug had some side effects.

Many patients reported headaches, although not many more than those taking a placebo. Six percent of the modafinil recipients complained of insomnia, compared to none in the placebo group.

And because the study lasted for only three months, the long-term effects of the treatment are unknown.

In an editorial in the journal, Robert Basner of the Columbia University College of Physicians and Surgeons in New York, said the new study does not "justify writing more prescriptions for modafinil."

Instead, he said, it's "a wake-up call" for more research to address "the serious health and safety issues that surround us by virtue of our having become, to a large extent, a shift-working society."