The FDA today approved suvorexant (Belsomra) tablets to treat patients who have difficulty with falling and staying asleep.
As an orexin receptor antagonist, suvorexant alters the signaling of chemicals in the brain involved in regulating the sleep-wake cycle, which plays a key role in keeping individuals with insomnia awake.
Insomnia is a common condition in which a patient has trouble falling or staying asleep. In addition to causing daytime sleepiness and lack of energy, insomnia can also make an individual feel anxious, depressed, or irritable, and those with insomnia may have trouble with attentiveness, learning, and memory.
As a treatment for insomnia, suvorexant should be taken no more than once per night, within 30 minutes of going to bed and with at least 7 hours remaining before the planned time of waking, the FDA advised. The total once-daily dose should not exceed 20 mg.
“To assist health care professionals and patients in finding the best dose to treat each individual patient’s sleeplessness, the FDA has approved Belsomra in 4 different strengths: 5, 10, 15, and 20 mg,” said Ellis Unger, MD, director of the Office of Drug Evaluation I in the FDA’s Center for Drug Evaluation and Research, in a press release
. “Using the lowest effective dose can reduce the risk of side effects, such as next-morning drowsiness.”
The most common adverse event reported by clinical trial participants taking suvorexant was drowsiness. The FDA warned that insomnia medications can cause next-day drowsiness and impair driving and other activities that require alertness, and patients taking these medications can be impaired even when they feel fully awake.
In light of these risks, the agency asked Merck Sharpe & Dohme Corp, the maker of suvorexant, to study next-day driving performance in those who had taken the tablet. The testing showed impaired driving performance in both male and female participants when the 20 mg strength was taken, so the FDA said patients using the 20 mg strength should be cautioned against next-day driving or activities requiring full mental alertness. Because there is individual variation in sensitivity to the drug, patients taking lower doses should also be made aware of the potential for next-day driving impairment, the agency noted.
The effectiveness of the drug was studied in 3 clinical trials that involved more than 500 participants. In the studies, patients taking suvorexant fell asleep faster and spent less time awake during the remainder of the night compared to those taking placebo. Because Belsomra was not compared to other drugs approved to treat insomnia, it is not known whether there are differences in safety or effectiveness between suvorexant and other insomnia medications.
Like other sleep medicines, suvorexant carries a risk of sleep-driving and performance of other complex behaviors while not being fully awake, such as preparing and eating food, making phone calls, and having sex. Chances of such activity increase if a person has consumed alcohol or taken other medicines that make them sleepy. If this type of activity occurs, patients or their families should call the prescribing health care professional, the FDA advised.
Because Belsomra is a controlled substance that can be abused or lead to dependence, it will be dispensed with an FDA-approved patient Medication Guide that provides instructions for its use and important safety information.