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Harmony Biosciences Initiates Clinical Trial of Pitolisant for Prader-Willi Syndrome

February 24, 2020 - Harmony Biosciences has listed its phase 2 study to evaluate the safety and efficacy of pitolisant in patients with Prader-Willi Syndrome (PWS). ( The study will include an 11-week double-blind treatment phase (including a 3-week titration period and an 8-week stable dose period), and an optional open label extension phase. The investigators will soon be enrolling 60 patients ages 6 to 65 years.

The clinical trial represents the culmination of the scientific, policy, and advocacy work of Chion Foundation, whose mission is to improve the quality of lives of families touched by PWS and other rare diseases. Chion Foundation was the first to identify pitolisant as a treatment for PWS after its president, Lara C. Pullen, PhD, hypothesized that sleep-related issues were not only more common than reflected in the medical literature, but also represented an opportunity for drug development. Working with Trend Community, Chion Foundation upended conventional thinking about PWS and communicated the importance of sleep to the pharmaceutical community.

PWS is a complex genetic condition that it Is typically characterized by obesity, excessive hunger, and low tone. Another pervasive symptom, sleepiness, is often neglected. “There is no denying that hunger and obesity are problems in the PWS community,” explained Lara C, Pullen, PhD, president and co-founder of Chion Foundation. “The thing is that the pharmaceutical community has not yet been able to deliver a drug that relieves those symptoms of PWS and improves the quality of lives of patients with PWS and their families. We think that a different strategy, tackling sleepiness, may be able to achieve all of those goals.”

Maria Picone is the CEO and cofounder of TREND Community, a community and analytics platform which leverages participant-contributed real-world data to better understand rare disease and accelerate the path to treatment. She and Dr. Pullen co-founded Chion Foundation. “We analyzed caregiver conversations from closed Facebook groups and our findings validated Lara’s hypothesis. The PWS community frequently discuss issues related to sleep,” explained Ms. Picone. “In fact, terms associated with sleep were used far more often than terms for hunger,” she added.

The PWS community has long noted sleepiness as a problem in their children. Not only are infants with PWS extraordinarily sleepy, but children with PWS exhibit classic signs of cataplexy, a loss of muscle tone associated with the rare disease of narcolepsy, which is characterized by excessive daytime sleepiness. Unfortunately, this observation has been neglected by clinical research, and PWS is currently treated as an endocrinological disease with growth hormone as its only approved therapy. Only now are neurologists beginning to be incorporated in the regular care of patients with PWS.

Since its formation in 2016, Chion Foundation has increased awareness of the prevalence of narcolepsy/cataplexy in the PWS population and described the role of the histamine H3 receptor in both cataplexy and hunger. Their web site and blog posts have driven many members of the PWS community to sleep professionals who have subsequently given diagnoses of narcolepsy and cataplexy to children with PWS. Pitolisant has now been approved and available in the US for the treatment of narcolepsy and cataplexy. Chion Foundation is hopeful that the phase 2 clinical trial in PWS will reinforce the finding that pitolisant can also address other foundational issues of PWS, first highlighted by the Chion Foundation in its peer-reviewed and published case series.


Lara C. Pullen, Maria Picone, Litjen Tan, Charles Johnston, and Holger Stark (2019) Cognitive Improvements in Children with Prader-Willi Syndrome Following Pitolisant Treatment—Patient Reports. The Journal of Pediatric Pharmacology and Therapeutics: March-April 2019, Vol. 24, No. 2, pp. 166-171.

About Chion Foundation

Chion Foundation is a nonprofit, tax-exempt charitable organization under Section 501(c)(3) of the Internal Revenue Code. The mission of the Chion Foundation is to improve the quality of lives of families touched by Prader-Willi Syndrome (PWS) and other rare diseases. For more information, please visit

Contacts for Media

Lara C. Pullen, PhD –

Maria Picone -




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