**Study Summary: Evaluating ALKS 2680 for Daytime Sleepiness** This study aims to check if ALKS 2680 tablets are safe and effective in reducing daytime sleepiness in people with a condition called Idiopathic Hypersomnia. Idiopathic Hypersomnia is a disorder where people feel very sleepy during the day, even if they sleep well at night. Participants will either receive ALKS 2680 or placebo (a tablet with no medicine) to compare results. **Key Points:** - **Eligibility**: Participants must have been diagnosed with Idiopathic Hypersomnia and be willing to follow study rules, such as keeping sleep diaries and using special sleep tracking devices. - **Exclusions**: Individuals with other sleep disorders or significant health issues, recent involvement in other studies, or who are pregnant or breastfeeding cannot participate. - **Study Requirements**: Participants must comply with lifestyle and therapy guidelines, especially if they are being treated for conditions like Obstructive Sleep Apnea (OSA). This study is essential for those who have been struggling with excessive daytime sleepiness and are looking for new treatment options. Participants' safety and adherence to study guidelines are crucial throughout this research.