Longer studies needed
In an accompanying editorial, Kai Spiegelhalder, PhD, University of Freiburg, Germany, and colleagues pointed out that although insomnia disorder is defined by self-reported difficulty initiating or maintaining sleep, none of the primary or secondary endpoints in these trials addressed these symptoms.
However, Dr. Mignot noted the use of the IDSIQ scale is the most interesting aspect of the study. Although difficulty with concentration and mood impairment are major symptoms of insomnia, they are often neglected. “This drug was reversing the daytime impairment that insomniacs have,” said Dr. Mignot. “We now need to systematically study people not only for the effect on sleep, but also that it makes them feel better the day after.”
He added that most of the current hypnotics were not developed to treat insomnia. Daridorexant, in contrast, targets the wake-promoting orexin system. “It works more selectively on sleep and not on other things. Most of the other sleeping pills have more complex effects on the brain,” Dr. Mignot said.
Commenting on the study, John Winkelman, MD, PhD, professor of psychiatry at Harvard Medical School, Boston, said the low prevalence of side effects associated with daridorexant was remarkable. “This is not what most of the benzodiazepine receptor agonists looked like,” said Dr. Winkelman, who was not involved with the research.
Many insomnia drugs affect transmitter systems that are widespread in the brain, thus provoking side effects. But orexin-receptor antagonists “don’t seem to produce a lot of side effects,” he noted.
Although the study duration was reasonable, longer studies will be necessary, he added. “And it would be nice to see comparative data. Prescribers want to see some context.” said Dr. Winkelman.
The study was funded by Idorsia Pharmaceuticals. Dr. Mignot reported receiving research or clinical trial funding from Axsome, Jazz Pharmaceuticals, Avadel, Apple, Huami, Sunovion, and Takeda. He has also received consulting fees or speakers’ conference reimbursement from Idorsia, Centessa Pharmaceuticals, Jazz Pharmaceuticals, Avadel, Dreem, and Takeda. Dr. Winkelman has consulted for Idorsia and has participated in investigator-initiated studies supported by Merck.
A version of this article first appeared on Medscape.com.