FDA panel green-lights lower doses of Merck’s sleep agent suvorexant

May 23, 2013

Panel splits on safety of drug at higher doses

Soon after FDA expressed concerns over the higher dosages and safety profile, including daytime drowsiness, of the proposed sleep agent known as suvorexant (Merck), the Agency’s Peripheral and Central Nervous System Drugs Advisory Committee voted 13 to 3, with one abstention, in favor of the safety of two proposed starting doses for the drug - 15 mg in patients over the age of 65 and 20 mg in patients under the age of 65.

Panel members had different reactions to the question of the safety of the product at higher doses; seven voted that the drug was safe, eight found it unsafe, and two abstained.

In a company announcement, Merck stated that the company is “excited about the potential of suvorexant as a new and different approach to treating insomnia, a serious condition that affects up to one-third of the adult population.  [The] votes and discussion bring us one step closer to providing physicians with another option to help patients struggling with insomnia. We look forward to working with the FDA as the agency continues its review of our application.”

Suvorexant functions differently from other insomnia treatments currently available. An orexin receptor antagonist, it was developed to block the neurotransmitters (orexins) found to foster waking states of consciousness in the brain and in so doing, support the sleep process. If suvorexant wins FDA approval, this novel approach to combating sleep disturbance would make suvorexant the first in a new class of drugs.

FDA will take the committee’s recommendations for suvorexant under consideration while it reviews Merck’s New Drug Application (NDA). According to Merck, FDA should announce its decision on suvorexant around the middle of the year.

The US Drug Enforcement Administration usually performs a schedule assessment and determination after FDA approves a drug. Once these evaluations are made, the drug should become commercially available.