The Food and Drug Administration (FDA) approved a calcium, magnesium, potassium, and sodium oxybates oral solution (Xywav; Jazz Pharmaceuticals, Philadelphia, PA) on July 21, 2020 for the treatment of cataplexy or excessive daytime sleepiness (EDS) in individuals age 7 years and more with narcolepsy. The oxybate compound has a unique composition resulting in 92% less sodium, or approximately 1,000 to 1,500 mg less per night, compared with the already available sodium oxybates at the recommended dosage range of 6 to 9 g/night.
The FDA approval of the oxybates compound is based on a global phase 3 double-blind placebo-controlled randomized-withdrawal multicenter study that demonstrated the statistically significant improvement (P<.0001) in the number of weekly cataplexy attacks and Epworth sleepiness scale scores for those treated with the oxybate compared with those treated withplacebo.
Multiple dosing options are available for adult and pediatric patients. Prescribers can titrate the oxybate compound into unequal doses taken over the course of the night. When starting the new oxybates compound in someone who has been using sodium oxybate, the starting dose for the new oxybates is as they were taking sodium oxybate (gram for gram) and titrated as needed based on efficacy and tolerability.
“Based on the efficacy demonstrated in the clinical program, the approval of the oxybates compound is important for people living with cataplexy or EDS associated with narcolepsy. 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,” said Richard K. Bogan, MD, FCCP, FAASM, associate clinical professor at the University of South Carolina School of Medicine, a medical officer at SleepMed in Columbia, SC and lead investigator of the phase 3 study. “The average American consumes too much sodium. Excess sodium intake has been linked with increases in blood pressure, hypertension, stroke, and other cardiovascular disease.”
“We have been working for nearly a decade to develop Xywav, a unique oxybate product with a significant reduction in sodium. We are proud to advance the science behind our sleep research program in order to continue making a difference for people living with narcolepsy,” said Bruce Cozadd, chairman and chief executive officer of Jazz Pharmaceuticals. “Jazz is committed to addressing unmet needs in sleep medicine, which includes our innovative and long-standing oxybate program.”
Nupur Ghoshal, MD, PhD
Adam M. Staffaroni, PhD; Elena Tsoy, PhD; Jack Taylor, BS; Adam L. Boxer, MD, PhD; and Katherine L. Possin, PhD
Henrik Zetterberg, MD, PhD; Deborah O.T. Alawode, BSc; Ashvini Keshavan, MRCP, PhD; Antoinette O’Connor, MRCPI; Philip S. J. Weston, MRCP, PhD; Ross W. Paterson, MRCP, PhD; Amanda Heslegrave, PhD; Nick C. Fox, MD, FRCP, FMedSci; Michael P. Lunn, FRCP, PhD; and Jonathan M. Schott, MD, FRCP