Actelion Ltd announced that the first phase-III study with almorexant (RESTORA 1) has met its primary endpoint, superiority of the dual orexin receptor antagonist almorexant compared to placebo on objective and subjective wake after sleep onset (WASO). The finding was highly significant (p<0.001). In addition, several secondary endpoints of the study were met with statistical significance.

In RESTORA 1, the use of almorexant was well-tolerated. However, in this study as well as in the ongoing non-pivotal program, certain safety observations were made that will require further evaluation and assessment in longer-term phase-III studies. The phase-III studies are currently in preparation - in both adults and elderly patients suffering from primary insomnia - and will evaluate long-term efficacy and safety.

Professor Jed Black and VP Sleep Development at Actelion, commented, "In this two-week study, almorexant has demonstrated clinically meaningful effects on both sleep induction and sleep maintenance for patients suffering from primary insomnia. I am especially encouraged that these effects were maintained both throughout the night and throughout the 16-day treatment period."

Jean-Paul Clozel, MD and chief executive officer of Actelion, commented, "As a result of the use of an active reference arm of zolpidem 10mg in RESTORA 1, we have now obtained a first promising insight of the impact of our dual orexin receptor antagonist almorexant compared to the impact of a traditional GABA-agonist."

Jean-Paul Clozel concluded, "Additional studies are being planned to further establish the clinical profile of almorexant. We will explore aspects of sleep quality, absence of addiction and improved next-day performance. Chronic use studies in both adults and elderly will further evaluate the safety profile of this innovative agent."

Actelion has initiated a comprehensive phase-III programme named RESTORA (REstore physiological Sleep with The Orexin Receptor antagonist Almorexant) to evaluate safety and efficacy of 100 and 200 mg doses in adults and elderly patients diagnosed with primary insomnia.

Actelion's research team is targeting the G-Protein coupled receptors (GPCRs) that mediate the actions of orexins. Orexins are neuropeptide modulators produced in the brain to regulate alertness and reward seeking.

Almorexant is a first-in-class dual orexin receptor antagonist which has the potential to shift the paradigm for treating sleep disorders.

Actelion Ltd is a biopharmaceutical company with its corporate headquarters in Allschwil/Basel, Switzerland.