The 34th Annual Meeting of the Associated Professional Sleep Societies, or “SLEEP 2020,” was held last week from August 27th through the 30th. According to BioSpace, pharmaceutical company Harmony Biosciences presented four posters during the course of the conference. Of these, three involved post-hoc analyses of WAKIX (pitolisant). These analyses examined the safety, efficacy, and tolerability of WAKIX for patients with narcolepsy and cataplexy.
SLEEP 2020 Presentations
As stated before, three of Harmony’s presentations centered around WAKIX (pitolisant), an orally administered tablet to treat excessive daytime sleepiness (EDS) in patients with narcolepsy. The therapy is both FDA- and EMA-approved. Additionally, it also received Orphan Drug Designation. WAKIX is a selective histamine 3 (H3) receptor antagonist / inverse agonist. According to ScienceDirect, a receptor antagonist is one:
that, when binding to a neurotransmitter receptor, attenuates or completely blocks the neurotransmitter-mediated response, while on its own does not provoke a biological response.
WAKIX should not be used for patients with severe liver issues, long QT symptom, or cardiac issues. In clinical trials testing the efficacy of WAKIX for patients with narcolepsy and cataplexy, side effects included nausea, anxiety, insomnia, irritability, abdominal discomfort, increased heart rate, low appetite, headache, and dry mouth.
Presentation 1: Time-to-Response during Treatment
In this first presentation, Harmony analyzes the time it took for patients to respond to WAKIX. Additionally, it explores how long it took for the drug to stimulate a reduction in cataplexy and sleepiness. Researchers sourced data from two clinical trials: HARMONY 1 and HARMONY CTP. During these studies, patients received a maximum 35.6 mg WAKIX daily. In comparison to a placebo, WAKIX significantly improved Epworth Sleepiness Scale (ESS) Scores by weeks 2 and 3.
Presentation 2: WAKIX Efficacy in Patients with High Sleepiness and Cataplexy
Similarly, this presentation used data from the HARMONY 1 and HARMONY CTP trials. Researchers utilized participants with narcolepsy who experienced severe EDS and cataplexy. Again, researchers saw a significant improvement in ESS scores in patients taking WAKIX. In fact, 68.5% of patients responded to treatment and reduced scores by at least ≥3. 35.2% reduced scores by ≤10, compared to only 9.3% of the placebo group. Participants also experienced better sleep and less cataplexy events. While there were some small side effects, they were not serious. The most common side effect was a headache.
Presentation 3: Cardiac Safety and WAKIX
In the third and final presentation, researchers analyzed the relationship between WAKIX and cardiac health. In addition to HARMONY 1 and HARMONY CTP trials, researchers also sourced data from the HARMONY 3 clinical trial. Cardiovascular conditions are sometimes considered co-morbidities of narcolepsy. As a result, it is important that narcolepsy therapies are not too challenging for the patients.
The analysis considered 166 patients. Of these, 51.2% received WAKIX and 48.8% received a placebo. There were some cardiac changes noted. Mean heart rate increased slightly, as did blood pressure. One patient experienced sinus tachycardia, another palpitations, and another a right bundle branch block. While no patients had severe adverse reactions, the potential cardiac problems are something to consider.
Narcolepsy
Narcolepsy is a chronic neurological and sleep disorder which causes extreme daytime sleepiness and random sleep attacks. Patients may fall asleep for seconds, minutes, or even hours. In patients with narcolepsy, the brain isn’t able to regulate the normal sleep-wake cycle. Doctors are not sure of the exact cause of narcolepsy. However, many hypothesize that the condition relates to hypocretin deficiency. In some cases, patients also experience cataplexy, a sudden loss of muscle control and muscle tone associated with narcolepsy. Generally, narcolepsy with cataplexy is considered Type 1 narcolepsy, while narcolepsy without cataplexy is considered Type 2 narcolepsy.
Cataplexy is characterized by sudden, uncontrollable muscle weakness or paralysis. In many cases, cataplexy is triggered by fear, excitement, anger, or even laughter. Any strong emotional response can trigger cataplexy.
Learn more about narcolepsy.
