Once-nightly sodium oxybate was associated with a statistically significant reduction in cataplexy episodes among patients with narcolepsy, explained Michael Thorpy, MD, director of the Sleep-Wake Disorders Center at Montefiore Medical Center and professor of neurology at Albert Einstein College of Medicine.
At SLEEP 2022, Michael Thorpy, MD, director of the Sleep-Wake Disorders Center at Montefiore Medical Center and professor of neurology at Albert Einstein College of Medicine, discussed the results of the REST-ON trial, which focused on the effects of FT218 in patients with narcolepsy.
Can you discuss the results of the REST-ON trial?
The REST-ON trial is a trial that was done by a pharmaceutical company called Avadel. It was with this medication called FT218, which is a once-nightly form of sodium oxybate. Sodium oxybate we've had available to us since 2002, so we have a lot of experience with it. But one of the difficulties with the medication is that it needs to be taken twice at night and many patients don't want to wake up in the middle of a night to take a second dose of the medication. So this new medication, FT218, is a once-nightly formulation of sodium oxybate; the patient takes it prior to going to bed at night and then the 1 dose will serve them through the night and relieve their daytime symptoms of narcolepsy.
The study that was done was a parallel design study comparing placebo against FT218. What they looked at was the effect on sleepiness during the daytime. The prime outcome measure was an objective measure of sleepiness called the Maintenance of Wakefulness Test. They showed significant improvements in the Maintenance of Wakefulness Tests, indicating that patients are able to remain more awake and alert during the day after receiving the once-nightly form of sodium oxybate at night.
In addition to that, they looked at cataplectic episodes and showed that the number of cataplectic episodes were reduced. There was a statistically significant reduction in the cataplexy that patients were experiencing. The results of the study indicated that the once-nightly formulation was as effective as the twice-nightly administration of sodium oxybate, but had that added benefit that patients only have to take 1 dose rather than taking 2 doses.
What implications might these findings have for clinicians treating patients with narcolepsy?
Patients, at the moment, have a variety of medications that are available to them for the treatment of narcolepsy, but oxybate is regarded as the most effective medication for treating not only the sleepiness during the daytime but also the cataplexy. Also, it improves the quality of sleep at night because most patients—particularly those with type 1 narcolepsy—when they have cataplexy also have very disturbed sleep at night, and oxybate is very effective at improving that. But a lot of patients have difficulty taking the current dose form of oxybate, which requires a second dose 2-and-a-half to 4 hours after the first one, so they're taking it in the middle of the night. Some patients have difficulty in awakening to take that second dose. So, for some patients, the twice-nightly formulation leads to reduced benefit for the patient because they may only be able to take 1 dose of it.
The new formulation of the once nightly form of sodium oxybate has that advantage that patients just need to take that 1 dose before going to bed, so it's much easier for the patient and they won't forget to take a second dose because the second dose isn't needed, and they won't have the need to awaken in the middle of the night to take another dose. It's a much more patient-acceptable format for oxybate.