The Food and Drug Administration has approved the dual orexin receptor antagonist daridorexant (Quviviq) for the treatment of insomnia in adults, the drug’s manufacturer, Idorsia, has announced.
The FDA’s decision was based partly on a phase 3 trial of adults with moderate to severe insomnia who were randomly assigned to receive 25 or 50 mg of daridorexant or matching placebo. Daridorexant was associated with dose-dependent improvements in wake after sleep onset, total sleep time, and latency to persistent sleep.
Whereas the overall results are very positive, the improvements in daytime functioning are especially “exciting,” Thomas Roth, PhD, director of the Sleep Disorders and Research Center at Henry Ford Hospital in Detroit, said in an interview.
“That’s sort of a big deal. For me, that’s the biggest deal there is,” said Dr. Roth, who was a consultant on the design of the phase 3 trial and on the interpretation of the data.
The drug will be available in doses of 25 mg and 50 mg, and the FDA has recommended that it be classified as a controlled substance. After it is scheduled by the Drug Enforcement Administration, daridorexant is expected to be made available in May.
Favorable safety profile
Insomnia is a common disorder characterized by difficulty falling asleep or staying asleep and by early-morning awakenings. Patients with insomnia often report fatigue, irritability, and difficulty with concentration. The condition can also result in significant problems with work and social activities, thus contributing to anxiety or depression.
As with other dual orexin receptor antagonists, daridorexant competitively binds with both orexin receptors in the lateral hypothalamus to block the activity of orexin in a reversible way. This approach decreases the downstream action of the wake-promoting neurotransmitters that are overactive in patients with insomnia.
The phase 3 trial measured daytime functioning using the new Insomnia Daytime Symptoms and Impacts Questionnaire (IDSIQ), a patient-reported outcome instrument. Daridorexant was associated with significant improvements in daytime function, particularly in sleepiness and mood.
Previous trials of other dual orexin receptor antagonists did not use the IDSIQ as an outcome, so it is not possible to compare daridorexant with those drugs in this respect, Dr. Roth noted. Researchers also have not conducted head-to-head trials of the drug with other dual orexin receptor antagonists.
Daridorexant also had a favorable safety profile and was not associated with rebound insomnia or withdrawal effects. The most common adverse events were headache and somnolence or fatigue.
“They had no effect on sleep stage distribution [and] they had no significant effects on sleep and breathing in people with mild to moderate sleep apnea,” said Dr. Roth, who presented the phase 3 findings at SLEEP 2020.
In addition to serving as a consultant for Idorsia on the trial design and interpretation of results, Dr. Roth has also served as a consultant for other companies that develop sleep agents.
A version of this article first appeared on Medscape.com.