This study looks at a medicine called ORX750 for people with narcolepsy and idiopathic hypersomnia. Narcolepsy is when you feel very sleepy during the day, and idiopathic hypersomnia means you sleep too much without knowing why. The study focuses on how safe ORX750 is, how the body uses it (called pharmacokinetics or PK), and how it works in the body (called pharmacodynamics or PD). To join, you should be between 18 and 65 years old and have a Body Mass Index (BMI) between 17 and 37. You must have a diagnosis of narcolepsy (Type 1 or 2) or idiopathic hypersomnia. You should stop taking any other medicines for these conditions and follow study rules. You cannot join if you have other medical issues causing sleepiness or serious health problems like heart or liver disease.

• Study tests the safety and effects of ORX750.
• Participants must stop other treatments for narcolepsy or hypersomnia.
• Eligible participants are 18-65 years old with specific health criteria.