Merck sleep aid Belsomra OK'd by FDA
This article was originally published in Scrip
Merck investors can rest easy over the company's sleep aid Belsomra (suvorexant), a first-of-its-kind product, now that the FDA has finally given its blessing to the medicine – with the firm winning approval to market the drug at the 5mg, 10mg, 15mg and 20mg doses.
Shares of Whitehouse Station, New Jersey-based Merck got a 1.5% boost on 13 August on the news, before closing at $57.85, up 82 cents, or 1.4%.
Belsomra's approval had been in question last year after the FDA hit Merck's new drug application with a complete response letter citing the need for more manufacturing studies on the 10mg dosage form, which regulators demanded before approving the orexin receptor antagonist as a treatment for insomnia characterized by difficulties with sleep onset or maintenance (scripintelligence.com, 1 July 2013).
Merck said Belsomra is the result of more than a decade of neuroscience research – demonstrating "tangible evidence of our long-standing commitment to innovation."
Belsomra works by blocking the action of orexins, which are neurotransmitters in the brain that help to keep a person awake.
The FDA noted that Belsomra is the first orexin receptor antagonist approved in the US.
While the FDA called Belsomra a Schedule IV substance – meaning it can be abused or lead to dependence – Merck said regulators had only recommended it be classified by the Drug Enforcement Administration as a scheduled product and that agency has only proposed it at that level, but has not yet issued a final decision.
Therefore, Merck said, Belsomra "cannot become available before that decision."
Nonetheless, the company said it expected the new medicine to be available in the US in late 2014 or early 2015.
Like other insomnia drugs, Belsomra has a risk of patients engaging in "sleep-driving" and other complex behaviors while not being fully awake, such as preparing and eating food, making phone calls or having sex – adverse effects for which Sanofi's Ambien (zolpidem) and generic versions of that drug are notoriously known.
Regulators said the chances are increased of sleep driving and the other complex behaviors if a person mixes sleep aids with alcohol or other medicines that make them sleepy.
The FDA noted that medications that treat insomnia can cause next-day drowsiness and impair driving and other activities that require alertness – even impaired when people feel fully awake.
Indeed, last year, the FDA said it had received about 700 reports of zolpidem-related impaired driving, with some of those resulting in traffic accidents, which led to those products' recommended dosage being lowered (scripintelligence.com, 11 January 2013).
The agency in May also told Sunovion Pharmaceuticals to lower the recommended starting dose of its sleep aid Lunesta (eszopiclone), with generic makers directed to do the same with their versions of the drug (scripintelligence.com, 16 May 2014).
So the FDA advised using the lowest possible dose of Belsomra to avoid adverse effects, including next-morning drowsiness.
The FDA had earlier determined it would not approve Belsomra in the 30mg and 40mg doses Merck initially sought to market.
The drug's labeling warns that co-administration with benzodiazepines, opioids, tricyclic antidepressants or alcohol increases the risk of central nervous system (CNS) depression, and advises that dosage adjustments of Belsomra and CNS depressants may be necessary because of potentially additive adverse effects.
The labeling advises against use of Belsomra with other drugs to treat insomnia and warns that patients should not consume alcohol in combination with Merck's sleep aid.
And patients receiving moderate CYP3A inhibitors should only take the 5mg dose of Belsomra.
Belsomra's labeling notes that a variety of cognitive and behavioral changes, such as amnesia, anxiety, hallucinations and other neuro-psychiatric symptoms, have been reported in patents taking hypnotics like Belsomra.
Merck's drug is contraindicated in patients with narcolepsy.
The labeling advises prescribers to reevaluate a patient for co-morbid conditions if insomnia persists after more than 10 days of treatment with Belsomra.
Pharmacists must dispense a patient-friendly medication guide with Belsomra that provides safety information and instructions for the drug's use.