0756 A One Year Observational Early Access Pitolisant Study of Excessive Daytime Sleepiness in Narcolepsy

Introduction Pitolisant is a H3 receptor antagonist/inverse agonist that has been FDA approved for excessive daytime sleepiness in narcolepsy at doses of either 17.8 mg or 35.6 mg per day. Methods 13 patients (3 males and 10 females) were studied having an average age of 46.8 years, with the majority receiving a dose of 35.6 mg Pitolisant. One patient received 17.8 mg throughout the year, and another advanced after 6 months to the 35.6 mg dose due to hepatic issues. 12 of the patients were Caucasian and one was Asian. 100% of the patients had co-existing sleep and psychiatric disorders. 46% had co-existing sleep apnea and were on CPAP/BIPAP. 38.5% had a history of a head injury. 84.6% of the patients had associated cataplexy, 38% had sleep paralysis, 92% had disrupted nocturnal sleep, and 46% had hypnogogic hallucinations. Throughout the year the patients were monitored using the Epworth Sleepiness Scale (ESS). Nine patients completed the 12-month ESS scales. 12/13 were on other medications to treat narcolepsy prior to starting Pitolisant. 6/13 were on sodium oxybate, 7/13 were on an antidepressant, and 11/13 were on either a stimulant, modafanil, or armodafanil. Only one patient was on Pitolisant alone. Results The patient’s average ESS score at onset was 16.2 Statistically significant findings using paired t-tests were documented. After one-month ESS scores decreased to an average of 13.2 (t=2.38, 9df, P=.04). At 3 months it was 12.4 (t=2.81, 10df, P=.02), at 6 months it was 12.75 (t=4.69, 11df, P<.001) and at 12 months the average score was 13.11 (t=2.55, 8df, P=.03) documenting clinically meaningful decrease of ESS by >/= 3 points. Three patients had ESS scores </=10 at 12 months. Conclusion Improvement on ESS was documented at one month and sustained for one year in patients diagnosed with having narcolepsy both with and without cataplexy. Support **No support was given for this study. Dr. Stultz is a speaker for Harmony Biosciences and has served on their advisory committee. She is also a speaker for Jazz Pharmaceuticals.