The FDA has approved pitolisant (Wakix, Harmony Biosciences) for the treatment of excessive daytime sleepiness (EDS) in adult patients with narcolepsy. This is the first treatment for narcolepsy approved by the agency that is not considered a controlled substance by the Drug Enforcement Agency.
Pitolisant, a first-in-class medication, is a selective histamine 3 (H₃) receptor antagonist/inverse agonist that works to increase the synthesis and release of histamine. Patients take the oral treatment in the morning after awakening.
Narcolepsy is a sleep disorder characterized by excessive sleepiness, sleep paralysis, and hallucinations. It can also cause cataplexy, partial or total loss of muscle control. In most patients, narcolepsy is caused by the loss of hypocretin, a neuropeptide in the brain that supports sleep-wake state stability. Narcolepsy affects about 200,000 people in the United States.
Pitolisant was approved following two late-stage clinical studies, HARMONY 1 and HARMONY 1bis. Participants, 75% of whom had a history of cataplexy, received pitolisant or placebo over the course of eight weeks. In both of the studies, pitolisant showed a statistically significant improvement in excessive daytime sleepiness as measured by the Epworth Sleepiness Scale score. The most common adverse events were insomnia, nausea, and anxiety.
In May 2018, Wakix secured breakthrough therapy and fast track designations from the FDA, and the drug had also previously received an orphan drug designation.
Harmony Biosciences said it expects Wakix to be available to U.S. patients in the fourth quarter of 2019.
Source: BioSpace, August 15, 2019