A first drug in a new class of insomnia treatments was rejected by the Food and Drug Administration (FDA) because the agency said safety data didn’t support approval of the treatment at the dosing proposed. The drug, called suvorexant, made by Merck & Co., was under review by the FDA in both 30- and 40-milligram doses.
The FDA advised Merck that suvorexant was effective at doses as low as 10 milligrams up to 40 milligrams, with 10 milligrams seen as the starting point. As a result, the FDA advised that Merck seek approval for the lowest dosage before it grants approval at the higher levels.
An advisory panel for the FDA in May voted to recommend approval of the drug. The FDA is not required to follow the advice of its expert panels, but it usually does. Merck had initially proposed starting dosing at 15 to 20 milligrams based on age, with higher doses of 30 to 40 milligrams as needed. The panel didn’t think that extra studies would be necessary for doses of 10 milligrams.
If approved, suvorexant will be the first in a class of insomnia drugs called orexin receptor antagonists. The drug works by blocking the action of chemicals in the brain called orexins that help keep people awake. It works differently than currently available prescription sleep aids.
Not only does Merck have to gain FDA approval in order to market suvorexant, it must also obtain approval from the U.S. Drug Enforcement Administration.