What do people with insomnia and people with narcolepsy have in common? Trick question! I don’t know, but we may be coming closer to an answer.
In the late 90’s, narcolepsy researchers made a significant breakthrough in successfully identifying the brain cells, called hypocretin (or orexin), that go missing in those that develop narcolepsy. These brain cells help to control the sleep/wake cycle, so when they disappear, the sleep/wake cycle is not properly regulated and symptoms of narcolepsy develop.
Narcolepsy researchers continue to study this brain cell loss, trying to figure out why the degeneration takes place (now believed to be an autoimmune response due to multiple genetic and environmental co-factors).
The big breakthrough has yet to lead to better treatments for narcolepsy, but the potential is huge. “If we could get orexin into the brains of people with narcolepsy – and get it to the right places at the right times – we could, I think, completely cure this disease,’’ Dr. Thomas Scammell, a neurologist and prominent narcolepsy specialist at Beth Israel Deaconess Medical Center told the Boston Globe, “It would be like giving insulin to diabetics.’’(1)
Merck has worked for the past eight years on a novel insomnia drug that affects the hypocretin/orexin system, reports an informative news article today. Other insomnia medications bind with either GABA or melatonin receptors, which help people fall asleep, but don’t necessarily keep them asleep. Instead, Merck’s pipeline drug, called suvorexant, works by “binding to the brain’s orexin receptors and blocking hormones known as orexin peptides from signaling the body to wake up.”(2)
Merck’s suvorexant drug is currently in stage III clinical trials, estimated to wrap up in September 2011. (3)
Yet, the fate of suvorexant is still unclear. “Results of mid-stage studies showed the drug was ‘generally well-tolerated,’ according to a press release issued by Merck last year. Some of the side effects reported by study participants included upper respiratory tract infections, dizziness and vivid dreams.”(2)
Vivid dreams?! Hmm, sounds familiar. I hope Merck’s drug isn’t just a dose of narcolepsy. Or wait, is that the point? (I hope this drug gives individuals a healthy sleep architecture and simply isn’t putting them into REM.)
In all seriousness, I’m interested to watch the medication’s progress. The market potential for a successful insomnia treatment is huge (in 2010, total insomnia market value was $2.73 billion). I expect we will hear a lot more about this drug in the future.
Beyond the interests of the sleep-challenged amongst us, this story is important for exemplifying the unpredictable nature of scientific research. A discovery for narcolepsy may lead to an advancement for insomnia. There is also great potential for hypocretin/orexin-targeted treatments to help obesity and addiction. (3)
I hope narcolepsy has good karma for helping other disorders, and that this comes back our way eventually!