**Study Overview:** This study is testing a new medicine called *ALKS 2680* in adults with Narcolepsy Type 1 (NT1). NT1 is a sleep disorder that causes extreme daytime sleepiness and sudden muscle weakness called cataplexy. The study will compare how well ALKS 2680 works against a placebo, which is a pill that looks like the medicine but has no active ingredients. *Eligibility:* To join the study, you must have NT1 confirmed by tests like PSG/MSLT (which are sleep studies) or by checking your CSF hypocretin-1 levels (a brain chemical). You cannot join if you have other sleep disorders, serious illnesses, or if you're pregnant or breastfeeding. *Study Details:* - **Length:** The study will require multiple visits over a certain period. - **Risks:** Some risks might include side effects from the medicine. - **Compensation:** Check with the study site for any compensation offered. If you meet the requirements and are interested, you should discuss with your doctor to see if this study might be a good fit for you.