The US Food and Drug Administration (FDA) has approved an oral solution of calcium, magnesium, potassium, and sodium oxybates (Xywav, Jazz Pharmaceuticals) for treatment of cataplexy or excessive daytime sleepiness (EDS) in patients as young as age 7 years with narcolepsy.
Xywav is a novel oxybate product with a unique composition of cations, resulting in 92% less sodium than sodium oxybate (Xyrem, Jazz Pharmaceuticals) at the recommended dosage range of 6 to 9 grams, the company said in a news release.
The FDA approved the drug based on a phase 3 trial involving 201 patients who had narcolepsy with cataplexy.
As reported by Medscape Medical News from the World Sleep 2019 meeting, Xywav demonstrated highly statistically significant differences (P < .0001) in weekly number of cataplexy attacks (primary efficacy endpoint) and Epworth Sleepiness Scale scores (key secondary outcome) vs placebo.
"Based on the efficacy demonstrated in the clinical program, the approval of Xywav is important for people living with cataplexy or EDS associated with narcolepsy," lead investigator Richard K. Bogan, MD, said in the company's news release.
He noted that the average American consumes too much sodium. "Excess sodium intake has been linked with increases in blood pressure, hypertension, stroke, and other cardiovascular disease," said Bogan, University of South Carolina School of Medicine, Columbia, South Carolina.
"Xywav makes it possible for patients to have a lower-sodium oxybate treatment option. This may help patients taking sodium oxybate better align with daily sodium intake recommendations, including those by the American Heart Association," he added.
The overall safety profile of Xywav is in line with sodium oxybate, the company said. The most common adverse reactions in adults, occurring in at least 5% of participants, were headache, nausea, dizziness, decreased appetite, parasomnia, diarrhea, hyperhidrosis (excessive sweating), anxiety, and vomiting.
Xywav has a boxed warning as a CNS depressant and for its potential for abuse and misuse. As a result, the drug is only available through a Risk Evaluation and Mitigation Strategy (REMS) program.
The US Drug Enforcement Agency has designated Xywav as a schedule III drug, meaning it has a moderate to low potential for physical and psychological dependence.
The company plans to launch Xywav by the end of the year. Full prescribing information and a medication guide are available online.
Cite this: FDA Okays Low-Sodium Treatment Option for Narcolepsy - Medscape - Jul 22, 2020.