EDSPhase 3NCT07675135
A Phase 3 Efficacy and Safety Study of HBS-301 in Participants With Narcolepsy
A Phase 3 study testing HBS-301 in people with EDS and Cataplexy, run by Harmony Biosciences Management, Inc. at 53 sites in 2 countries.
Trial 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 excessive daytime sleepiness (EDS), cataplexy, sleepiness/wakefulness, and fatigue in adult participants (ages ≥18 years) with narcolepsy. Read more about this study
- Who is it for?
- Ages 18 years and older
- What is being tested?
- HBS-301
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 258 participants
- Where
- 53 sitesin 2 countries
- Study dates
- 4 Jun 2026to Nov 2027
- Phase
- Phase 3
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- 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.
Who cannot join
- 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 locations and contacts
53 sites in 2 countries. Contact the study team or a site near you to ask about taking part.
53 sites in 2 countries
United States51 sites, 51 recruiting
- Recruiting
Abington Neurological Associates
Abington, Pennsylvania, 19001
Rachel Grossman, (215) 957-9250, rachelgrossman.ana@gmail.com
John Khoury, MD
- Not yet recruiting
Neurology Care
Ardmore, Oklahoma, 73401
Maaz Ghani, (210) 363-5481, mghani@sunbeamresearch.com
Baha Abu-Esheh, MD
- Recruiting
Neurotrials Research Inc
Atlanta, Georgia, 30328
Shriya Parekh, 404-851-9934, sparekh@neurotrials.com
Dennis Lacey, MD
- Recruiting
Aayus Research
Austin, Texas, 78731
Maria-Fernanda Gamero, (803) 606-2052, Maria@aayus.co
Bhavim Desai, MD
- Not yet recruiting
Sleep Disorders Center of Alabama
Birmingham, Alabama, 35213
Joseph Wright, (205) 599-1020, jwright@sleepalabama.com
Robert Doekel, MD
- Recruiting
Alpine Clinical Research Center, Inc
Boulder, Colorado, 80301
Federica Bresciani, (601) 520-1333, fika@alpineresearch.com
John R Harsh, PhD
- Recruiting
Lowcountry Lung and Critical Care PA
Charleston, South Carolina, 29406
Courtney Arnold, (843) 572-8545, carnold@lowcountrylung.com
Thomas D Kaelin Jr, DO
- Not yet recruiting
Medical University of South Carolina
Charleston, South Carolina, 29425
Brooke Cameron, 843-876-9262, camerobr@musc.edu
Thomas Uhde, MD
- Recruiting
St. Lukes Sleep Medicine and Research Center
Chesterfield, Missouri, 63017
Kimberly Allen-Bowzer, (314) 205-6011, SLHSleepResearch@stlukes-stl.com
Michael McLeland, PhD
- Recruiting
Intrepid Research, LLC
Cincinnati, Ohio, 45245
Tiffany Schira, (513) 977-8891, tschira@intrepidresearch.md
Bruce C Corser, MD
- Not yet recruiting
The Cleveland Clinic Foundation
Cleveland, Ohio, 44195
Alex Piczer, (216) 445-2990, piczera@ccf.org
Nancy Foldvary-Schaefer, DO
- Recruiting
Delta Waves LLC
Colorado Springs, Colorado, 80918
Emma Gallagher, (719) 262-9283, egallagher@deltawaves.org
Jonathan Olin, MD
- Recruiting
Bogan Sleep Consultants, LLC
Columbia, South Carolina, 29201
Lorraine Potts, (803) 251-3093, Lorraine.Potts@bogansleep.com
Richard Bogan, MD
- Recruiting
Southwest Family Medicine
Dallas, Texas, 75235
Safia Shaikh, (469) 893-1242, sshaikh@swmedicalgroup.com
Chrisette Dharma, MD
- Not yet recruiting
Geisinger Medical Center
Danville, Pennsylvania, 17821
Cheryl Pysher, (570) 271-8254, crpysher@geisinger.edu
Anne Marie Morse, DO
- Not yet recruiting
Research Carolina Elite LLC
Denver, North Carolina, 28037
Heather Micun, RMA, CRC, 704-817-2200, Heather@researchcarolinaelite.com
704-817-2200
- Not yet recruiting
Infinity Medical Research Inc
East Providence, Rhode Island, 02914
Patricia Mello, (508) 998-3041, pmello@infinitymedicalresearch.com
Curtis Mello, MD
- Not yet recruiting
Fort Wayne Neurological Center
Fort Wayne, Indiana, 46804
James Stevens, (260) 436-2416, pcase@iuhealth.org
James Stevens, MD
- Recruiting
Clinical Research of Gastonia
Gastonia, North Carolina, 28054
Melissa Lanham, 704-675-7144, mlanham@crgastonia.com
Anup Banerjee, MD
- Not yet recruiting
NorthShore University HealthSystem
Glenview, Illinois, 60026
Anna Pham, (847) 570-2570, Anna.Pham@endeavorhealth.org
Mari Viola-Saltzman, DO
- Recruiting
Stern Research Partners
Huntersville, North Carolina, 28078
Felix Kurniawan, 704-659-0090, felix@arsmnc.com
Thomas Stern, MD
- Not yet recruiting
University of Kansas Hospital Main Campus
Kansas City, Kansas, 66160
Whitney Theis, (913) 588-6045, wtheis2@kumc.edu
Damien Stevens, MD
- Not yet recruiting
West Coast Pulmonary & Sleep Disorders Center
Lancaster, California, 93534
Stephanie Nava, 805-483-1185, snava@fomatmedical.com
Raj Bhatia, MD
- Recruiting
Santa Monica Clinical Trials
Los Angeles, California, 90025
Samantha Montanez, (310) 586-0843, smontanez@smclinicaltrials.com
Daniel Norman, MD
- Recruiting
Sleep Practitioners, LLC
Macon, Georgia, 31210
Noelle Williams, (478) 745-5779, nwilliams@sleeppractitioners.com
Charles C Wells, Jr, MD
- Not yet recruiting
University of Wisconsin-Madison
Madison, Wisconsin, 53719
Ahmad Allen, (608) 232-3333, aallen45@wisc.edu
David Plante, MD, PhD
- Not yet recruiting
Metroplex Pulmonary and Sleep Center
McKinney, Texas, 75069
Rupa Krishna, (972) 838-1892, rkrishna@mpsleepcenter.com
Shahrukh Kureishy, MD
- Recruiting
PharmaDev Clinical Research Institute, LLC
Miami, Florida, 33176
Rolando Rodriguez, (305) 420-5636, rrodriguez@pharmadevresearch.com
Edward Mezerhane, MD
- Not yet recruiting
Patient First MD
Middletown, New Jersey, 07748
Avraham Tuvy, (732) 629-9699, tuvya@patientfirstmd.com
Matthew Davis, MD
- Not yet recruiting
Springhill Medical Center
Mobile, Alabama, 36608
Kennedy Green, (251) 278-6022, kennedy.green@amr-clinical.com
Michael Ledet, MD
- Not yet recruiting
West Virginia University Hospital
Morgantown, West Virginia, 26506
Lauren Chase, 304-598-4000, lauren.chase@wvumedicine.org
Mouhannad Azzouz, MD
- Not yet recruiting
K2 Medical Research - Nashville
Nashville, Tennessee, 37204
Francesca McKay, (615) 208-5252, francesca.mckay@k2med.com
Joshua Lennon, MD
- Not yet recruiting
Northwell Health Physician Partners
New Hyde Park, New York, 11042
Kirendra Pasram, (516)-465-5441, kpasram1@northwell.edu
Harly Greenbergh, MD
- Not yet recruiting
Henry Ford Medical Center
Novi, Michigan, 48377
Michaela Mogle, (248) 344-6672, mmogle1@hfhs.org
Christopher Drake, PhD
- Recruiting
Phoenix Medical Group, PC
Peoria, Arizona, 85381
Daniel Kasenovich, (623) 583-6542, dkasenovich@phxresearch.com
Robert Orr, DO
- Not yet recruiting
OSF St Francis Medical Center
Peoria, Illinois, 61606
Kimberly Hartwig, (309) 672-5682, kimberly.hartwig@osfhealthcare.org
Patrick Whitten, MD
- Not yet recruiting
University of Pittsburgh
Pittsburgh, Pennsylvania, 15213
Steve Swanger, (412) 383-0607, swangersm2@upmc.edu
Venkatesh Krishnamurthy, MD
- Recruiting
Stanford Center for Sleep Sciences and Medicine
Redwood City, California, 94063
Sara Lomba, (650) 799-1565, slomba@stanford.edu
Oliver Sum Ping, MD
- Recruiting
Southeast Lung Associates Research
Rincon, Georgia, 31326
Lisa Rodnicki, (912) 826-3927, lisa.rodnicki@centricityresearch.com
Maria Mascolo, MD
- Recruiting
Sleep Therapy & Research Center
San Antonio, Texas, 78229
Erin Marshall, (210) 614-6000, marshall.erin@sleeptrc.com
Nagwa Lamaie, MD
- Not yet recruiting
HasResearch
San Antonio, Texas, 78240
Kimberly Rosales, (210) 614-7711, kimberly.rosales@hasresearch.com
Hernan Salazar, DO
- Not yet recruiting
University of California San Francisco
San Francisco, California, 94107
Kyra Powers, (415) 823-3227, kyra.powers@ucsf.edu
Andrew Krystal, MD
- Recruiting
Trial Site Solutions
San Ramon, California, 94583
Phil Strauss, (925) 415-5353, phil@sleepmds.com
Haramandeep Singh, MD
- Recruiting
Revive Research Institute, Inc
Southfield, Michigan, 48075
Abhishek Dhillon, (248) 564-1485, adhillon@rev-research.com
Syed Raza, MD
- Recruiting
Sleep and Performance Research Center
Spokane, Washington, 99202
Olivia Brooks, (509) 358-7754, olivia.brooks@wsu.edu
Devon Hansen, PhD
- Recruiting
Clinical Neurophysiology Services
Sterling Heights, Michigan, 48314
Jessica Austin, (586)-254-0707, austinj@sleepandattentiondisorders.com
Shaffi Kanjwal, MD
- Recruiting
Clinical Research Institute Stockbridge
Stockbridge, Georgia, 30281
Beverley Jenkins, (678) 782-5358, bjenkins@clinicalresearchinstitute.us
Phillip Nowlin, MD
- Recruiting
Tricoastal Narcolepsy and Sleep Disorders Center
Sugar Land, Texas, 77478
Natalia Dubock, (832) 210-3850, research@tricoastalsleep.com
Gerry Meskill, MD
- Not yet recruiting
TPMG Clinical Research
Williamsburg, Virginia, 23188
Gabrielle Land, (757) 707-3503, Gabrielle.Land@tpmgpc.com
Richard Parisi, MD
- Recruiting
Florida Pediatric Sleep Disorders Institute
Winter Park, Florida, 32789
Heidi Patenaude, (407) 898-2767, heidi@ajayihealthcare.com
Akinyemi O Ajayi, MD
- Recruiting
Berks Schuylkill Respiratory Specialists
Wyomissing, Pennsylvania, 19610
Lisa Hill, (610) 685-5864, lhill@lungmd.net
Alec Platt, MD
Canada2 sites, 2 recruiting
- Recruiting
AMNDX Inc
Markham, Ontario, M5S 3A3
Urszula Lamoureux, 416-435-6244, urszula@amndx.ca
Alan Lowe
- Recruiting
Jodha Tishon Inc
Toronto, Ontario, M5S 3A3
Naheed Hossain, (416) 551-8296, naheedkhossain@jodhatishon.com
Colin Shapiro
About this study
Official title: A Phase 3, Randomized, Double-blind, Placebo-Controlled, Efficacy and Safety Study of HBS-301 in Participants With Narcolepsy Followed by an Open-label Extension
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.
Read the 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 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.
- Conditions
- EDS, Cataplexy, Fatigue, Narcolepsy
- Being tested
- HBS-301, Placebo
- Keywords
- pitolisant, HBS-301, narcolepsy, EDS, cataplexy, fatigue
- Medical subject headings
- Cataplexy, Fatigue, Narcolepsy
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
HBS-301Drug
Also called pitolisant delayed-release
HBS-301 tablet
PlaceboOther
Placebo tablet
| Study group | Role | What they receive |
|---|---|---|
| Double-Blind Treatment Period HBS-301 | Experimental | HBS-301 tablets administered once daily in the morning upon wakening Receives: Drug: HBS-301 |
| Double-blind Treatment Period Placebo | Placebo comparator | Matching placebo tablets administered once daily in the morning upon wakening Receives: Other: Placebo |
| Open-Label Extension Period HBS-301 | Experimental | HBS-301 tablets administered once daily in the morning upon wakening Receives: Drug: HBS-301 |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in severity of EDS as measured by the Epworth Sleepiness Scale (ESS)
The ESS is an 8-item, 4-point rating scale.
Measured: Baseline to end of Double-Blind Treatment Period (8 weeks)
Secondary outcomes (19)
Change in Weekly Rate of Cataplexy (WRC) in participants with an average WRC of ≥3 over 2 consecutive weeks at Screening
The WRC is the average number of cataplexy attacks per week.
Measured: End of the Double-Blind Treatment Period (8 weeks)
Change in sleepiness/wakefulness measured by the Maintenance of Wakefulness Test (MWT)
The MWT consists of a series of 20-minute to 40-minute trials spaced 2 hours apart and is used to measure an individual's ability to stay awake.
Measured: Baseline to the end of the Double-blind Treatment Period (8 weeks)
Change in fatigue as measured by the Patient-Reported Outcomes Measurement Information System Fatigue Short Form 7a (PROMIS-Fatigue-SF-7a)
The PROMIS-Fatigue-SF-7a is a 7-question, 5-point scale used to assess fatigue.
Measured: Baseline to end of Double-Blind Treatment Period (8 weeks)
Change in severity of EDS as measured by the ESS
The ESS is an 8-item, 4-point rating scale.
Measured: Baseline through Week 1 and through Week 2 of Titration Period (1 week and 2 weeks)
Onset of efficacy of HBS-301 compared with placebo in treating cataplexy measured by WRC in participants with an average WRC of ≥3 over 2 consecutive weeks during Screening
The WRC is the average number of cataplexy attacks per week.
Measured: Baseline through Week 1 and Week 2 of the Titration Period (1 week and 2 weeks)
Change in severity of EDS as measured by the Clinical Global Impression of Change (EDS)
The Clinical Global Impression of Change (EDS) is a 7-point scale used to measure the improvement or worsening of the participant's EDS relative to a baseline.
Measured: Baseline to end of Double-blind Treatment Period (8 weeks)
Change in severity of EDS as measured by the Patient Global Impression of Severity (EDS)
The Patient Global Impression of Severity (EDS) is a participant-reported assessment that gauges the severity of a participant's EDS symptoms.
Measured: Time Frame: Baseline to the end of the Double-blind Treatment Period (8 weeks)
Improvement in the severity of EDS as measured by the Patient Global Impression of Change (EDS)
The Patient Global Impression of Change (EDS) is a participant-reported outcome used to evaluate the effectiveness of a treatment on their EDS symptoms.
Measured: Baseline to the end of the Double-blind Treatment Period (8 weeks)
Change in severity of cataplexy as measured by the Clinical Global Impression of Severity (Cataplexy) in participants with an average WRC of ≥3 over 2 consecutive weeks during Screening
The Clinical Global Impression of Severity (Cataplexy) is a 3-item observer-rated scale used to track cataplexy symptom changes.
Measured: Baseline to the end of the Double-blind Treatment Period (8 weeks)
Change in severity of cataplexy as measured by the Patient Global Impression of Severity (Cataplexy) in participants with an average WRC of ≥3 over 2 consecutive weeks during Screening
The Patient Global Impression of Severity (Cataplexy) is a participant-reported assessment that gauges the severity of cataplexy symptoms.
Measured: Baseline to the end of the Double-blind Treatment Period (8 weeks)
Improvement in severity of cataplexy as measured by the Patient Global Impression of Change (Cataplexy) in participants with an average WRC of ≥3 over 2 consecutive weeks during Screening
The Patient Global Impression of Change (Cataplexy) is a participant-reported outcome used to evaluate the effectiveness of a treatment on their cataplexy symptoms.
Measured: Baseline to the end of the Double-blind Treatment Period (8 weeks)
Change in severity of fatigue as measured by the Patient Global Impression of Severity (Fatigue)
The Patient Global Impression of Severity (Fatigue) is a participant-reported assessment that gauges the severity of a participant's fatigue symptoms.
Measured: Baseline to the end of Double-blind Treatment Period (8 weeks)
Change in severity of fatigue as measured by the Patient Global Impression of Change (Fatigue)
The Patient Global Impression of Change (Fatigue) is a participant-reported outcome used to evaluate the effectiveness of a treatment on their fatigue symptoms.
Measured: Baseline to the end of the Double-blind Treatment Period (8 weeks)
Change in severity of narcolepsy symptoms as measured by the Narcolepsy Severity Scale (for participants with NT1) or Narcolepsy Severity Scale-2 (for participants with NT2)
The Narcolepsy Severity Scale is a 15-item participant-reported questionnaire that assesses the severity and consequences of narcolepsy symptoms.
Measured: Baseline to the end of the Double-blind Treatment Period (8 weeks)
Change in cognitive complaints as measured by the British Columbia Cognitive Complaints Inventory
The British Columbia Cognitive Complaints Inventory is a participant-reported, 6-item, 4-point scale that assesses perceived cognitive difficulties.
Measured: Baseline to the end of the Double-blind Treatment Period (8 weeks)
Change in health-related quality of life as measured by the Short Form-36 physical and mental component summaries
The Short Form-36 includes 36 questions across 8 health domains to measure a participant's functional health and well-being.
Measured: Baseline to the end of the Double-blind Treatment Period (8 weeks)
Change in work productivity as measured by the Work Productivity and Activity Impairment: Narcolepsy work productivity loss score
The Work Productivity and Activity Impairment: Narcolepsy questionnaire is a 6-item scale used to measure impairments over 7 days.
Measured: Baseline to the end of the Double-blind Treatment Period (8 weeks)
Incidence of treatment-emergent adverse events
A treatment-emergent adverse event is any adverse event reported after the first dose of study drug and up to 30 days after final dose of study drug, or any worsening of a pre-existing condition reported after first dose of study drug and up to 30 days after final dose of study drug.
Measured: Throughout study (16 months, including Open-label Extension)
Evaluate the pharmacokinetic concentrations of pitolisant and major identified metabolites
Pharmacokinetics is the study of how the body interacts with administered substances for the duration of exposure.
Measured: Throughout study (16 weeks)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted30 Jun 2026
- Study start4 Jun 2026
- Primary completionOct 2027 (estimated)
- Study completionNov 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for EDSStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 3
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Triple blind
- Who is masked
- Participant, Investigator, Outcomes assessor
- Enrolment
- 258 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Harmony Biosciences Management, Inc.
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- David Seiden, MD, Study director, Harmony Biosciences Management, Inc.
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07675135
- Sponsor's protocol ID
- HBS-301-CL-301
- Other IDs
- 2025-523821-17-00, 2025
- Status last verified
- Aug 2026
- First submitted
- 22 Jun 2026
- Last updated
- 27 Aug 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 27 Aug 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 3, Randomized, Double-blind, Placebo-Controlled, Efficacy and Safety Study of HBS-301 in Participants With Narcolepsy Followed by an Open-label Extension
- ClinicalTrials.gov ID
- NCT07675135
- Acronym / sponsor ID
- HBS-301-CL-301
- Conditions
- EDS, Cataplexy, Fatigue, Narcolepsy
- Keywords
- pitolisant, HBS-301, narcolepsy, EDS, cataplexy, fatigue
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 258 participants (estimated)
- Lead sponsor
- Harmony Biosciences Management, Inc.Industry (pharma, biotech, devices)
- Study start
- 4 Jun 2026 (actual)
- Primary completion
- Oct 2027 (estimated)
- Study completion
- Nov 2027 (estimated)
- First posted
- 30 Jun 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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.
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 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.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Triple blind (participant, investigator, outcomes assessor)
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| Double-Blind Treatment Period HBS-301 | Experimental | Drug: HBS-301HBS-301 tablets administered once daily in the morning upon wakening |
| Double-blind Treatment Period Placebo | Placebo comparator | Other: PlaceboMatching placebo tablets administered once daily in the morning upon wakening |
| Open-Label Extension Period HBS-301 | Experimental | Drug: HBS-301HBS-301 tablets administered once daily in the morning upon wakening |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (3 listed)
- 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.
Key exclusion criteria (7 listed)
- 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.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| HBS-301Also: pitolisant delayed-releaseHBS-301 tablet | Drug | Double-Blind Treatment Period HBS-301, Open-Label Extension Period HBS-301 |
| PlaceboPlacebo tablet | Other | Double-blind Treatment Period Placebo |
Primary outcome
Change in severity of EDS as measured by the Epworth Sleepiness Scale (ESS)
Time frame: Baseline to end of Double-Blind Treatment Period (8 weeks)
The ESS is an 8-item, 4-point rating scale.
19 secondary outcomes
Change in Weekly Rate of Cataplexy (WRC) in participants with an average WRC of ≥3 over 2 consecutive weeks at Screening
Time frame: End of the Double-Blind Treatment Period (8 weeks)
Change in sleepiness/wakefulness measured by the Maintenance of Wakefulness Test (MWT)
Time frame: Baseline to the end of the Double-blind Treatment Period (8 weeks)
Change in fatigue as measured by the Patient-Reported Outcomes Measurement Information System Fatigue Short Form 7a (PROMIS-Fatigue-SF-7a)
Time frame: Baseline to end of Double-Blind Treatment Period (8 weeks)
Change in severity of EDS as measured by the ESS
Time frame: Baseline through Week 1 and through Week 2 of Titration Period (1 week and 2 weeks)
Onset of efficacy of HBS-301 compared with placebo in treating cataplexy measured by WRC in participants with an average WRC of ≥3 over 2 consecutive weeks during Screening
Time frame: Baseline through Week 1 and Week 2 of the Titration Period (1 week and 2 weeks)
Change in severity of EDS as measured by the Clinical Global Impression of Change (EDS)
Time frame: Baseline to end of Double-blind Treatment Period (8 weeks)
Change in severity of EDS as measured by the Patient Global Impression of Severity (EDS)
Time frame: Time Frame: Baseline to the end of the Double-blind Treatment Period (8 weeks)
Improvement in the severity of EDS as measured by the Patient Global Impression of Change (EDS)
Time frame: Baseline to the end of the Double-blind Treatment Period (8 weeks)
Change in severity of cataplexy as measured by the Clinical Global Impression of Severity (Cataplexy) in participants with an average WRC of ≥3 over 2 consecutive weeks during Screening
Time frame: Baseline to the end of the Double-blind Treatment Period (8 weeks)
Change in severity of cataplexy as measured by the Patient Global Impression of Severity (Cataplexy) in participants with an average WRC of ≥3 over 2 consecutive weeks during Screening
Time frame: Baseline to the end of the Double-blind Treatment Period (8 weeks)
Improvement in severity of cataplexy as measured by the Patient Global Impression of Change (Cataplexy) in participants with an average WRC of ≥3 over 2 consecutive weeks during Screening
Time frame: Baseline to the end of the Double-blind Treatment Period (8 weeks)
Change in severity of fatigue as measured by the Patient Global Impression of Severity (Fatigue)
Time frame: Baseline to the end of Double-blind Treatment Period (8 weeks)
Change in severity of fatigue as measured by the Patient Global Impression of Change (Fatigue)
Time frame: Baseline to the end of the Double-blind Treatment Period (8 weeks)
Change in severity of narcolepsy symptoms as measured by the Narcolepsy Severity Scale (for participants with NT1) or Narcolepsy Severity Scale-2 (for participants with NT2)
Time frame: Baseline to the end of the Double-blind Treatment Period (8 weeks)
Change in cognitive complaints as measured by the British Columbia Cognitive Complaints Inventory
Time frame: Baseline to the end of the Double-blind Treatment Period (8 weeks)
Change in health-related quality of life as measured by the Short Form-36 physical and mental component summaries
Time frame: Baseline to the end of the Double-blind Treatment Period (8 weeks)
Change in work productivity as measured by the Work Productivity and Activity Impairment: Narcolepsy work productivity loss score
Time frame: Baseline to the end of the Double-blind Treatment Period (8 weeks)
Incidence of treatment-emergent adverse events
Time frame: Throughout study (16 months, including Open-label Extension)
Evaluate the pharmacokinetic concentrations of pitolisant and major identified metabolites
Time frame: Throughout study (16 weeks)
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 27 Aug 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
David Seiden, MD study director
Harmony Biosciences Management, Inc.
53 sites in 2 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 3 study testing HBS-301 in people with EDS and Cataplexy, run by Harmony Biosciences Management, Inc. at 53 sites in 2 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 7 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 27 Aug 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 53 sites in United States, Canada. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Michelle Manuel (847-903-4610, clinicaltrials@harmonybiosciences.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change in severity of EDS as measured by the Epworth Sleepiness Scale (ESS) (time frame: Baseline to end of Double-Blind Treatment Period (8 weeks)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 27 Aug 2026.