A Phase 3 interventional study of FT218 in Narcolepsy, Cataplexy and Excessive Daytime Somnolence, sponsored by Avadel. Completed at 29 sites in 2 countries. Open to participants aged 16 Years and older. Per ClinicalTrials.gov, last updated 2025-10-02.
Sponsored by Avadel (part of Alkermes, Inc.) · Phase 3, Interventional, and Treatment
An Open Label Study to Evaluate Long-Term Safety and Tolerability of a Once Nightly Formulation of Sodium Oxybate for Extended-Release Oral Suspension (FT218) and the ability to switch from twice-nightly immediate release sodium oxybate to once-nightly FT218 for the Treatment of Excessive Daytime Sleepiness and Cataplexy in Subjects with Narcolepsy
This study will enroll subjects with narcolepsy, either NT1 or NT2, who completed the FT218 Phase 3 REST-ON study or eligible subjects with narcolepsy currently receiving a stable dose of twice nightly sodium oxybate IR or mixed salts oxybate (regardless of whether they participated in the REST-ON study), or subjects who are naïve to oxybate therapy (i.e., FT218, twice nightly sodium oxybate IR or mixed salts oxybate). Following a screening period, subjects who meet the entry criteria will be enrolled into the study. Subjects who completed the FT218 Phase 3 REST-ON study will initiate treatment with FT218 at 4.5 g and will follow a titration schedule up to the highest tolerate dose (up to 9 g), or the dose deemed effective by the investigator. Subjects previously maintained on twice nightly sodium oxybate IR will initiate FT218 treatment at a dose equivalent or closest to the total gram dose of twice-nightly sodium oxybate IR and then titrate up or down, in accord with safety and effectiveness as determined by the investigator.
31 studies on the registry are indexed under Cataplexy; 5 are open to participants now.
This study's enrollment of 184 is above the median of 117 across 27 interventional studies indexed under Cataplexy.
Browse Cataplexy studies →Avadel is the lead sponsor of 4 studies on the registry; none are open to participants now.
First submitted before Avadel became part of Alkermes, Inc..
Compared within Cataplexy, this study's primary condition as ClinicalTrials.gg classifies it; the registry's first condition term is Narcolepsy. The counts are of registry records indexed under each term, refreshed daily. How we classify →
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Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
once nightly sodium oxybate extended release oral solution (FT218)
Drug: FT218
once nightly sodium oxybate extended release
Incidence of treatment-related adverse events
Assess the long-term safety and tolerability of FT218 by the number of participants experiencing treatment-related adverse events
Time frame: 24 months
Incidence of clinically significant changes in vital signs
Assess the long-term safety and tolerability of FT218 by the number of participants experiencing clinically significant changes in vital signs
Time frame: 24 months
Incidence of clinically significant changes in laboratory test results
Assess the long-term safety and tolerability of FT218 by the number of participants experiencing clinically significant changes in laboratory test results
Time frame: 24 months
Plan to share: No
Ran from Jun 2020 to primary completion in Dec 2023, 42 months.
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This study is completed, as verified in Sep 2025. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: FT218