Harmony Biosciences has begun the Phase III INTUNE clinical trial of its Wakix (pitolisant) tablets to treat adult patients with idiopathic hypersomnia (IH).

The placebo-controlled, randomised, double-blind withdrawal trial will enrol nearly 200 IH patients at 60 to 80 trial sites in the US. 

Assessing the efficacy and safety of pitolisant versus placebo to treat EDS in adult IH patients is the primary objective of the trial.

The impact of the therapy on other key IH symptoms, such as sleep inertia and cognitive impairment will be included as the trial’s secondary objectives.

In the trial, various other outcomes, including subject impression of overall change in symptoms, investigator-analysed overall disease severity and functional status will also be assessed.

A selective histamine 3 (H3) receptor antagonist/inverse agonist, Wakix was designed and developed by Bioprojet.

Bioprojet granted an exclusive licence to Harmony for developing, producing and marketing pitolisant in the US.

Wakix obtained the US Food and Drug Administration approval to treat excessive daytime sleepiness (EDS) or cataplexy in adults with narcolepsy.

Harmony chief medical officer Jeffrey Dayno said: “There has been much interest by both the patient community and healthcare professionals in pitolisant for the treatment of IH and we are excited about the initiation of our Phase III INTUNE study in adult patients with this rare neurological disorder. 

“Given the novel mechanism of action of pitolisant, which works through histamine, an important wake-promoting neurotransmitter in the brain, we are looking to translate innovative science into therapeutic possibilities that have the potential to improve the health of people living with IH.”

A rare and chronic neurological ailment, IH causes EDS in spite of adequate or even long sleep time.