A Phase 3 Efficacy and Safety Study of HBS-301 in Participants With Narcolepsy

Harmony Biosciences Management, Inc.

Status and phase: Enrolling; Phase 3

Conditions: Cataplexy; EDS; Fatigue; Narcolepsy

Treatments: Drug: HBS-301; Other: Placebo

Study type: Interventional

Funder types: Industry

Identifiers

NCT07675135

HBS-301-CL-301

2025-523821-17-00 (EU Trial (CTIS) Number)

Details and patient eligibility

About

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 excessive daytime sleepiness (EDS), cataplexy, sleepiness/wakefulness, and fatigue in adult participants (ages ≥18 years) with narcolepsy.

Full 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 EDS, cataplexy, sleepiness/wakefulness, and fatigue in adult participants (ages ≥18 years) with narcolepsy.

Approximately 258 participants are planned for randomization into 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 Period (1 year), and 30 days of safety follow-up.

Enrollment: 258 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Has a current documented diagnosis of NT1 or NT2 per the International Classification of Sleep Disorders, Third Edition (ICSD-3) or the ICSD-3 Text Revision (ICSD-3-TR) within the last 10 years.
• Has EDS.
• If taking a permitted chronic concomitant medication or supplement, including nonprohibited antidepressants or wake-promoting agents, must be on a stable dose for at least 3 months prior to Screening and agree to continue at that stable dose for the Double-blind Treatment Period of the study. As needed (PRN) use of any treatment that could affect daytime sleepiness (including but not limited to oxybates, stimulants, modafinil, and armodafinil) is not permitted.

Exclusion criteria

• Has hypersomnia due to another medical disorder.
• Has a history of pitolisant use within 5 half-lives prior to Screening.
• Has a primary diagnosis of psychiatric illness, including depression, that is not well controlled (i.e., symptoms and medications have not been stable for at least 3 months prior to Screening).
• Has any history of bipolar disorder or psychosis
• Has acute or chronic liver disease or a history of moderate or severe hepatic impairment.
• Has a body surface area-corrected estimated glomerular filtration rate (eGFR) <60 mL/min.
• Has a known history of long QT syndrome or serious abnormality of the electrocardiogram (ECG).

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Triple Blind

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258 participants in 3 patient groups, including a placebo group

Double-Blind Treatment Period HBS-301

Experimental group

Description:

HBS-301 tablets administered once daily in the morning upon wakening

Treatment:

Drug: HBS-301

Double-blind Treatment Period Placebo

Placebo Comparator group

Description:

Matching placebo tablets administered once daily in the morning upon wakening

Treatment:

Other: Placebo

Open-Label Extension Period HBS-301

Experimental group

Description:

HBS-301 tablets administered once daily in the morning upon wakening

Treatment:

Drug: HBS-301