Merck & Co has presented late-stage data on its eagerly-anticipated insomnia drug suvorexant which showed that the treatment improved patients' ability to fall and then stay asleep.

The drugs major has unveiled results from two Phase III trials for suvorexant at the Associated Professional Sleep Societies meeting in Boston, involving 2,030 insomniacs. In the studies, the first-in-class orexin receptor antagonist, significantly reduced the time it took patients to fall asleep and increased the time that patients stayed asleep as early as the first night and at the three-month time point compared to placebo; indeed it achieved statistical significance on 15 of 16 primary endpoints.

Specifically, two doses of the drug were studied and in the high dose trial, 40mg, suvorexant reduced the time it took to fall asleep by 25.7 minutes and helped patients sleep 60.3 minutes longer than prior to starting treatment. That compared with a time to sleep reduction of 17.3 minutes and 40.6 minutes more sleep on placebo.

Also suvorexant patients entered into continuous sleep 36 minutes faster (compared with 26.6 minutes faster for placebo) and spent less time awake during the night - 47.9 minutes less versus 25 minutes.

In the low dose trial, 30mg, suvorexant reduced the time it took participants to fall asleep by 33.7 minutes versus 20.5 minutes for placebo  and helped them to sleep an average of 62.8 minutes longer (versus 37.7 minutes for placebo). Patients spent 54.2 fewer minutes awake during the night than before they started taking suvorexant, compared with 24.8 minutes for the placebo group.

The most common adverse events reported at an incidence of greater than or equal to 5% and more often than placebo were sleepiness and headache. Other data presented included results that demonstrated the effects of suvorexant after daily dosing for at least a year and Merck noted that this is "one of the longest continuously-dosed, placebo-controlled trials of a sleep medication ever conducted".

Andrew Krystal of the Duke University Medical Center said the drug targets insomnia "in a way that is different from other medicines". He added that "the potential for a new and different option would be welcome by patients with insomnia who cannot sleep through the night". Merck plans to file suvorexant with the US Food and Drug Administration later this year.

Darryle Schoepp, head of the neuroscience and ophthalmology franchise at  Merck Research Laboratories, said that "suvorexant approaches insomnia differently than other medicines because it helps patients to sleep by targeting and blocking orexins, which play a role in keeping people awake".