NCT07500090

A Phase 3 Efficacy and Safety Study of HBS-301 in Participants With Idiopathic Hypersomnia (IH)

A Phase 3, Randomized, Double-blind, Placebo-Controlled, Efficacy and Safety Study of HBS-301 in Participants With Idiopathic Hypersomnia (IH) Followed by an Open-label Extension

• Status: Recruiting
• Phase: Phase 3
• Study type: Interventional
• Enrollment: 248 (estimated)
• Sponsor: Harmony Biosciences Management, Inc. · Industry
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

This is a Phase 3, multicenter, randomized, double-blind, parallel-group, placebo-controlled clinical study to assess the efficacy and safety of HBS-301 in treating idiopathic hypersomnia (IH) symptoms, including excessive daytime sleepiness (EDS), sleep inertia, and fatigue in adult participants (ages ≥18 years) with idiopathic hypersomnia (IH). The primary objective of this study is to evaluate the efficacy of HBS-301 compared with placebo in treating IH symptoms. Secondary objectives include evaluating the efficacy of HBS-301 compared with placebo in treating EDS, sleep inertia, and fatigue.

Detailed description

This is a Phase 3, multicenter, randomized, double-blind, parallel-group, placebo-controlled clinical study to assess the efficacy and safety of HBS-301 in treating IH symptoms, including EDS, sleep inertia, and fatigue in adult participants (ages ≥18 years) with IH. Approximately 248 participants are planned for randomization in the study. The study will consist of a Screening/Baseline Period (up to 28 days), a Double-blind Treatment Period (8 weeks), an optional Open-label Extension (OLE) Period (1 year), and 30 days of safety follow-up.

Conditions

• Idiopathic Hypersomnia

Interventions

Type	Name	Description
DRUG	HBS-301 tablet	HBS-301 tablet
DRUG	Placebo	Placebo tablet

Timeline

• Start date: 2026-03-16
• Primary completion: 2027-10-01
• Completion: 2028-10-01
• First posted: 2026-03-30
• Last updated: 2026-03-30

Locations

12 sites across 1 country: United States

Regulatory

• FDA-regulated drug study