Home › Trials › NCT06366464

Evaluating pitolisant for excessive daytime sleepiness in Prader-Willi syndrome

A Phase 3, Randomized, Double-Blind, Placebo-controlled, Efficacy and Safety Study of Pitolisant Followed by an Open-Label Extension in Patients With Prader-Willi Syndrome

Phase 3 Interventional Harmony Biosciences Management, Inc. · NCT06366464

This study is testing if a medication called pitolisant can help reduce excessive daytime sleepiness in people aged 6 and older with Prader-Willi syndrome.

Quick facts

PhasePhase 3
Study typeInterventional
Enrollment134 (estimated)
Ages6 Years and up
SexAll
SponsorHarmony Biosciences Management, Inc. Industry-sponsored
Locations54 sites (Los Angeles, California and 53 other locations)
Trial IDNCT06366464 on ClinicalTrials.gov

What this trial studies

This Phase 3 clinical study investigates the efficacy and safety of pitolisant in treating excessive daytime sleepiness in patients aged 6 and older with Prader-Willi syndrome. The study is randomized, double-blind, and placebo-controlled, involving multiple centers globally. Participants will undergo a screening period followed by a treatment phase where they will receive either pitolisant or a placebo. Secondary objectives include assessing the drug's impact on behavioral issues such as irritability and hyperphagia.

Who should consider this trial

Good fit: Ideal candidates are individuals aged 6 and older with a genetically confirmed diagnosis of Prader-Willi syndrome and excessive daytime sleepiness.

Not a fit: Patients with uncontrolled sleep apnea or hypersomnia due to other medical disorders may not benefit from this study.

Why it matters

Potential benefit: If successful, this treatment could significantly improve daytime alertness and overall quality of life for patients with Prader-Willi syndrome.

How similar studies have performed: While this approach is novel for Prader-Willi syndrome, similar studies have shown promise in treating excessive daytime sleepiness in other conditions.

Eligibility criteria

Show full inclusion / exclusion criteria 
Inclusion Criteria:

* Genetically confirmed diagnosis of PWS
* Excessive daytime sleepiness
* Has a consistent parent/caregiver (preferably the same person throughout the study) who is willing and able to complete the required study assessments.
* In the opinion of the Investigator, the patient/parent(s)/caregiver(s)/legal guardian(s) are capable of understanding and complying with the requirements of the protocol and administration of oral study drug.

Exclusion Criteria:

* Has a diagnosis of sleep apnea (OSA, CSA) that is not adequately controlled
* Has a diagnosis of hypersomnia due to another sleep/medical disorder
* Participation in an interventional research study involving another investigational medication, device, or behavioral treatment within 30 days or 5 half-lives (whichever is longer) of the investigational medication prior to Screening

Where this trial is running

Los Angeles, California and 53 other locations

+4 more sites — see ClinicalTrials.gov for the full list.

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
View on ClinicalTrials.gov → Find more trials like this →
Conditions Prader-Willi Syndromepitolisantexcessive daytime sleepinessirritable and disruptive behaviorsPrader-Willi syndrome
Last reviewed 2026-06-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.