Jim Giles

Ethicists fear that people might misuse a new drug, known as CX717, to work long hours.

A drug being studied as a potential treatment for Alzheimer's can also counter the effects of sleep deprivation, a new study suggests. The finding has sparked debate over the use of 'lifestyle' drugs, which people take to make themselves feel smarter or more alert, rather than for a specific medical condition.

Developers of the drug, known as CX717, say it is meant to treat a range of debilitating mental conditions. But bioethicists point out that it could easily follow in the footsteps of other treatments that are being prescribed 'off-label', such as modafinil, a narcolepsy drug that is gaining popularity as a pick-me-up pill.

On 22 August, researchers at Wake Forest University Baptist Medical Center in Winston-Salem, North Carolina, published the results of trials of CX717 in monkeys. Animals that had been deprived of sleep for up to 36 hours - equivalent to 72 hours in humans - experienced cognitive deficits that virtually disappeared after taking the drug (L. J. Porrino et al. PLoS Biol. doi:10.1371/journal.pbio.0030299)1. Rested animals that were given CX717 also did better on cognitive tests than control animals. The drug works by boosting the uptake by brain receptors of the neurotransmitter glutamate.

The results in monkeys support findings from an unpublished human trial, funded by the company that makes the drug. In that study, 16 men kept awake overnight did better on a range of memory and attention tests when dosed with CX717; those suffering the most from tiredness received the biggest boost in performance. "We didn't see any adverse events," says Julia Boyle, who ran the study at the University of Surrey in Guildford, UK.

The drug's developer, Cortex Pharmaceuticals of Irvine, California, is pushing ahead with trials in patients with Alzheimer's and attention deficit hyperactivity disorder, as well as with people working night shifts. Bioethicists say that the drug may find other 'lifestyle' uses, perhaps by allowing workaholics to work longer days.

In a similar case, modafinil (sold under trade names including Provigil) was licensed in the United States as a treatment for sleepiness caused by narcolepsy in 1998 by Cephalon of Frazer, Pennsylvania, and later for other specific sleep disorders.

If CX717 can keep users awake as well as modafinil, with an added cognitive boost, experts worry that it could be misused by tired office workers or students with essay deadlines. "This could coerce people into staying awake an extra two hours," says Arthur Caplan, a bioethicist at the University of Pennsylvania in Philadelphia.

The US Defense Advanced Research Projects Agency is already funding studies designed to assess whether CX717 could help soldiers stay more alert.

Roger Stoll, chairman of Cortex Pharmaceuticals, says that his company is focusing only on clinical disorders in which CX717 might help. Still, he admits, "we don't know what everyone will do with it".