A Study of Pitolisant in Patients With Prader-Willi Syndrome

To join this study, people need to have a confirmed diagnosis of Prader-Willi syndrome through a genetic test. They must also experience excessive sleepiness during the day. It's very important that there's a parent or caregiver, preferably the same person throughout, who can help with the study tasks and assessments.

The study also needs to be sure that the patient, their parents, or caregivers understand what's involved and can follow the study instructions, including how to take the medicine by mouth.

However, some things might prevent someone from joining. For example, if someone has sleep apnea (a condition where breathing stops and starts during sleep) that isn't properly managed, they can't take part. Also, if their sleepiness is caused by a different sleep problem or medical condition, they wouldn't be suitable. Finally, if they've recently taken part in another study involving a new medication or treatment within the last month or so, they would also not be eligible.

If you decide to join this study, your journey begins with a 'Screening/Baseline' period that can last up to 45 days. During this time, the research team will do tests and ask questions to make sure you're a good fit for the study. Once all checks are complete and you meet the requirements, you'll be assigned either Pitolisant or a matching dummy pill (placebo).

During the main treatment part of the study, which is 'double-blind' (meaning neither you nor your doctor knows if you're taking the real medicine or the placebo), you'll have in-person visits at the clinic on roughly Day 29, Day 57, and Day 77. These visits are important for monitoring your health and checking how you're responding to the treatment. If you choose not to continue into the next phase, there will be two follow-up phone calls or visits about 15 and 30 days after your last dose of the study medicine.

After the main treatment period, there's an optional 'Open-Label Extension' period. This means everyone in this part will receive Pitolisant, and everyone will know they are getting the active medicine. If you choose to continue, you'll have more in-person visits around Day 113, Day 260, and Day 441. Again, after your final dose of Pitolisant in this extended period, there will be two follow-up checks about 15 and 30 days later. The total duration of participation depends on whether you join the optional extension.