At the Sleep 2012 conference, Merck and Company presented a paper outlining their new insomnia drug, Suvorexant. Suxorexant (MK-4305) is called an orexin receptor antagonist. Orexins play a key role in stimulating wakefulness and energy expenditure. The way this drug works is to block the action of these orexins. The drug has already been tried on rats, dogs, rhesus monkeys and humans, and they have lots and lots of data. Merck just finished two Phase III studies (assessment of efficacy on humans with primary insomnia), and plans to apply to the FDA sometime in 2012 to go to market. They have spent eight years and perhaps $400 Million developing the drug – this truly is big business.
This the beginning of a new train of thinking about insomnia medication, because instead of inducing sleep – like every sleep drug out there (think benzodiazepines or antihistamines) – it inhibits wakefulness. If you click here you can see Merck’s data which really shows that Suvorexant increases sleep efficiency, reduces wakefulness after sleep onset, and reduces the latency to persistent sleep. The numbers are actually quite significant.
The apparent bonus to this (this information comes from Merck, so be sceptical) is that there are no real side effects, and very little probability for abuse. But, further to the unintended consequence point, Actelion and GlaxoSmithKline had an orexin receptor antagonist (named Almorexant) in their pipeline for introduction as well, but they cancelled it because of side effect profile. The immediate question that comes to mind is “what is so different about the Merck drug”?
So I don’t really know what to think about all this – it almost sounds too good to be true. If it really does what they tell us it does, and has an insignificant side effect profile, Merck might just own the sleep-aid market a couple of years from now. A market that some analysts estimate could reach $7.7 billion in a few years time.



