A Study of TAK-861 for the Treatment of Narcolepsy Type 1

The drug being tested in this study is called TAK-861 (oveporexton). TAK-861 (oveporexton) is being tested to evaluate its efficacy and safety in people with narcolepsy type 1 (NT1). The study will enroll approximately 152 patients. Participants will be randomly assigned (by chance, like flipping a coin) to one of the three treatment groups: 1. TAK-861 Dose 1 2. TAK-861 Dose 2 3. Placebo The study drug will be administered for 12 weeks. This multi-center trial will be conducted globally.