Actelion's research team is targeting the G-Protein coupled receptors, OX1 and OX2, which mediate the actions of orexins. Orexins are neuropeptide modulators produced in the brain to regulate alertness and reward seeking. For example, genetic defects of the orexin peptides, or their receptors, are associated with certain inherited sleep disorders. Orexins have been further associated with food consumption, physical activity, and metabolism in experimental animals. Orexins may also play a role in other conditions.

Actelion hypothesize that dual orexin receptor antagonism will inhibit wake-promoting neurocircuits, shifting the balance in favor of sleep-promoting circuits and thereby enabling sleep.