Samelisant for Narcolepsy: A Phase 3 Test for EDS and Cataplexy

Is this trial a fit for you?

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This is a randomized, double-blind, placebo-controlled study conducted at multiple centers to evaluate the efficacy and safety of Samelisant over 12 weeks in adults with narcolepsy (with or without cataplexy). Participants are assigned to Samelisant or placebo in parallel groups, and neither participants nor investigators know the assignment during the trial. Outcomes include daytime sleepiness, weekly cataplexy events, attention, alertness, quality of life, and overall narcolepsy symptoms, with safety monitoring throughout. Eligibility requires adults with narcolepsy, specific cataplexy history for NT1, sleep study parameters, and consent to adhere to the protocol.

Why it matters

Who can join: the full rules

Key Inclusion Criteria:

1. Body mass index ranging from 18 to 45 kg/m2 (both inclusive).
2. Narcolepsy with or without cataplexy (Narcolepsy Type 1 \[NT1\] or Narcolepsy Type 2 \[NT2\]) based on the International Classification of Sleep Disorders 3-TR/ Diagnostic and Statistical Manual of Mental Disorders (DSM-5-TR) criteria for the diagnosis of narcolepsy.
3. For NT1 only, current continuing presence of cataplexy as defined by participant report for the last 3 months and have average of ≥4 weekly cataplexy events during the last 2 weeks of the washout period.
4. At the screening Visit and the Baseline Visit, participants who are not on treatment for EDS must have ESS scores ≥12 (as assessed with a look-back period of 1 week).
5. A mean MWT time of \<12 minutes across the first 4 sessions at Baseline.
6. Willingness to complete the study protocol with full compliance with procedures and sign an informed consent form.
7. Able to show compliance with sleep diary entries for at least 5 times/week in the final 2 weeks of the screening Period (non-compliant participants will not be included).

Key Exclusion Criteria:

1. Median habitual wake-up time after 9 am as assessed by sleep diary, habitual sleep time of \<6 h and median habitual bedtime past 1 am, as determined by sleep diary entries.
2. Use of any investigational therapy within the 30-day period (or 5 half-lives, whichever is longer) prior to enrollment.
3. History of (within past 3 months) or current substance use disorder involving illicit drugs, alcohol, or marijuana, as per DSM-5-TR criteria. Alcohol and/or recreational drugs use within 24 hours of study visits is strictly prohibited.
4. Excessive caffeine (defined as \>600 mg/day) use at least 1 week prior to Baseline assessments and during the study.
5. Nicotine dependence that affects sleep (eg, a participant who routinely awakens at night to smoke).
6. If receiving stimulants, modafinil, oxybates, pitolisant, solriamfetol, bupropion or other treatments for narcolepsy, and unwilling or unable to complete weaning 2 weeks prior to Baseline visit (Day 1)
7. Clinically significant ECG abnormalities. Participants are excluded with a screening ECG Fridericia's correction of QT (QTcF) interval ≥450 msec for men and ≥470 msec for women obtained after 5-minute rest in a supine position using a digital ECG.
8. Concurrent use of hypnotics, tranquilizers, centrally acting H1 receptor antagonists, benzodiazepines, anticonvulsants, or clonidine, tricyclic antidepressants that have H1-antihistamine properties (clomipramine, protriptyline).
9. Adjunctive pharmacotherapy directed against cataplexy (including but not limited to venlafaxine, fluoxetine, and gamma hydroxybutyrate) is prohibited.
10. An occupation requiring variable shift work, variable wake times, night shifts, frequent overnight travel or expected overnight travel across \> 3 time zones during the study which disrupts sleep patterns and working remotely leading to inconsistent sleep duration.

Where it's running

• Bogan Sleep Consultants
  Columbia, South Carolina, United States Recruiting

Study contacts

• Study coordinator: Study Contact
• Email: narcolepsy@suven.com
• Phone: +9140 2319 3956

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

• HBS-301 for Narcolepsy: daily wakefulness and sleepiness improvement in adults

  This Phase 3 study tests HBS-301 vs placebo in adults with narcolepsy to see if it helps with daytime sleepiness, cataplexy, sleepiness, and fatigue.

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• Expanded-dosing Xywav vs placebo in narcolepsy and IH

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• Testing Lu AH69593 for safety and tolerance in healthy adults and people with narcolepsy

  This study tests whether Lu AH69593 is safe and well tolerated in adults, including those with narcolepsy, and looks at how the body processes the drug with and without food.

  Recruiting Phase 1 H. Lundbeck A/S · Helsinki and 1 other locations · NCT07613710

• E2086 for adults with narcolepsy: find the best dose compared with placebo

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• Exploring the effects of light and electrical stimulation on sleep disorders

  This study is testing if light therapy and brain stimulation can help people with sleep disorders like insomnia and narcolepsy get better sleep.

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• Registry to evaluate the safety of SUNOSI during pregnancy

  This study is trying to see if the medication SUNOSI is safe for pregnant women who have narcolepsy or sleep apnea and how it affects their babies.

  Recruiting at 2 sites Axsome Therapeutics, Inc. · Morrisville, North Carolina and 1 other locations · NCT06413420

How to take part

1. Review the eligibility criteria above with your treating physician.
2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.