Cataplexy Symptoms Are Reduced With Narcolepsy Therapy

Long-term use of pitolisant reduces sleepiness and other comorbidities of narcolepsy, according to results of the Harmony III study.

Pitolisant is an histamine H₃-receptor antagonist currently approved by the US Food and Drug Administration for the treatment of daytime sleepiness in patients with narcolepsy.

To evaluate the long-term safety and efficacy of pitolisant for narcolepsy, the researchers conducted the Harmony III study, which enrolled 102 adults with narcolepsy and an Epworth Sleepiness Scale score of 12 or higher. After a titration period, participants received pitolisant, up to 40 mg, once per day for 12 months.

Of the 102 participants enrolled at baseline, 68 completed the study (51 of whom had cataplexy).

Overall, Epworth Sleepiness Scale scores had decreased from study baseline by 4.6±0.6.

Pitolisant also reduced complete cataplexy by 76%, partial cataplexy by 65%, hallucinations by 54%, sleep paralysis by 63%, and sleep attacks by 27%.

The most common treatment-related adverse events included headache, insomnia, weight gain, anxiety, depressive symptoms, and nausea. Serious adverse events were reported in 7 participants but were not related to pitolisant.

“In this realistic study, the good safety and tolerability profile of pitolisant was confirmed over the 12-month treatment period in a majority of patients. The safety results of this trial are consistent with those reported in previous studies when pitolisant was administered for a shorter duration,” the researchers concluded.

—Amanda Balbi

Reference:

Dauvilliers Y, Arnulf I, Szakacs Z, et al; HARMONY III study group. Long-term use of pitolisant to treat patients with narcolepsy: Harmony III study. Sleep. 2019;42(11):zsz174. https://doi.org/10.1093/sleep/zsz174.