Merck & Co., Inc. Wins FDA Approval For New Type Of Sleeping Pill
August 14, 2014
By Jessica Wilson, BioSpace.com Breaking News Staff
Merck & Co., Inc. , a Whitehouse Station-based pharmaceutical company and the second largest drug maker in the US, yesterday received FDA approval for Belsomra, a novel treatment for insomnia. Merck’s shares rose 1.4 percent on the New York Stock Exchange on Wednesday to close at $57.85.
According to the National Institutes of Health (NIH), about 60 million Americans a year have insomnia frequently or for extended periods of time. Currently, the most commonly prescribed drug for the condition is zolpidem, a generic form of Ambien. Merck hopes to change that.
Suvorexant, the chemical name for Belsomra, is an orexin receptor antagonist and the first such approved by the FDA for sleep issues. The importance of orexin neurotransmitters in the sleep cycle was discovered by Emmanuel Mignot, a researcher at Stanford, in experiments with narcoleptic dogs. His research led to the conclusion that when orexin is present, the brain receives a signal to stay awake. When suvorexant is present, however, orexin receptors are less likely to receive orexin. In the absence of orexin signaling the brain to stay awake, a person falls asleep.
The chemistry of suvorexant contrasts with that of zolpidem, the generic form of Ambien, which involves the neurotransmitter GABA—gamma-aminobutyric acid. When GABA-recepetors are activated, the brain slows; Ambien promotes this process.
Because suvorexant targets sleep-wake signaling, as opposed to slowing down the entire brain, Merck scientists believe it will be more effective with fewer side effects than Ambien.
In a December 2013 New Yorker article by Ian Parker, entitled “The Big Sleep,” Parker traced Merck’s initial journey for FDA-approval of suvorexant. When discussing the difference between orexin antagonists, such as suvorexant, and GABA agonists, such as Ambien, Parker summarizes: “The unspoken promise of orexin antagonists, then, is sleep without stupidity.”
In the same article, Parker interviewed John Renger, a neuroscientist at Merck, who explained that Ambien affects the onset of insomnia, but does little to keep a person asleep, while suvorexant affects both onset and maintenance of sleep in a positive way.
Scientists ran three clinical trials, involving more than five hundred people, to test the drug. The results demonstrated that compared to the placebo, more patients fell asleep faster and spent less time awake during the remainder the of the night. Belsomra was not compared to other drugs for insomnia in these trials.
In May 2013, the FDA directed Merck to file for approval of the drug at lower doses, stating that safety data didn’t support sales of the 30 milligram and 40 milligram doses.
Yesterday, in a statement announcing FDA approval, Ellis Unger, M.D., director of the Office of Drug Evaluation I in the FDA’s Center for Drug Evaluation and Research, said, “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 four different strengths – 5, 10, 15, and 20 milligrams.”
The DEA has proposed to list Belsomra as a controlled substance with a Schedule IV designation. Schedule I drugs have the greatest potential for abuse; Schedule V have the least. This proposal indicates that the DEA believes potential for the abuse of Belsomra is low, but restrictions are needed, such as how often the drug can be refilled.
Once the DEA has issued its final decision on the scheduling of the drug—possibly as early as the end of 2014—Merck will begin selling Belsomra.
