The Woolcock Institute of Medical Research

Researchers at the Woolcock Institute of Medical Research have published new findings from a clinical trial investigating a novel therapy designed to improve wakefulness in people with central disorders of excessive sleepiness.

These disorders of hypersomnolence, narcolepsy type 1 (NT1), narcolepsy type 2 (NT2) and idiopathic hypersomnia (IH), are characterised by excessive daytime sleepiness and significantly impaired functioning and quality of life.

The study, published in the Journal of Sleep Research, investigated alixorexton (ALKS 2680), an oral selective orexin 2 receptor (OX2R) agonist, involved in regulating wakefulness and maintaining stable sleep-wake cycles.

The randomised phase 1b proof-of-concept study included 27 adults with NT1, NT2 and IH. Participants received single doses of alixorexton or placebo, with researchers assessing safety, tolerability and wakefulness.

Results showed that alixorexton was generally well tolerated, with no serious adverse events reported and no participants discontinuing treatment due to side effects. The study found statistically significant, clinically meaningful improvements in participants’ ability to stay awake (more improvements with higher doses). This was measured using the Maintenance of Wakefulness Test (MWT), as well as improvements in self-reported alertness.

The findings support targeting the orexin pathway as a therapeutic approach for people living with central disorders of hypersomnolence. The Woolcock was one of four site locations across Australia and the United States that conducted the study. Led by researchers from the Woolcock’s Sleep and Circadian Research Group, the findings will help inform ongoing research into treatments that improve wakefulness and reduce the burden of excessive sleepiness. The Woolcock is now recruiting for Phase 3 of the same study, along with other orexin agonist studies for people with narcolepsy. You can find out more about these trials and volunteer for research at the Woolcock on our Research Volunteer website.

Find out more

• Targeting Orexin 2 Receptors in Idiopathic Hypersomnia and Narcolepsy: A Randomised Phase 1b Proof-Of-Concept Study of Alixorexton
• Current Research Studies at the Woolcock
• Narcolepsy
• Sleep Studies at the Woolcock
• The Struggle to Stay Awake
• Our Sleep and Circadian Research group