**Study of HBS-201 (Pitolisant Delayed-release)** This study is designed to see how well a new medicine, HBS-201, works for adults with narcolepsy. Narcolepsy is a sleep disorder that makes people feel very sleepy during the day. In this study, the medicine is given in a therapeutic dose, which is a safe amount to start with, ranging from 17.8 mg to 35.6 mg. This dose is based on guidelines from the Food and Drug Administration (FDA) for a similar medicine called WAKIX. The study includes three parts: a Screening/Baseline Period that can last up to 30 days, a 2-week period where everyone takes the medicine (Open-Label Period), and a follow-up period of 30 days to check on safety. **Key Points:** - The study lasts for about 2 months, including all periods. - Participants must not have tried WAKIX before. - Participants should not have other serious health issues that could affect the study results. This study is for adults with specific types of narcolepsy and aims to help understand how well patients tolerate starting treatment with HBS-201.