Calcium, Magnesium, Potassium and Sodium Oxybates (Xywav®) in Sleep Disorders: A Profile of Its Use.

Narcolepsy and idiopathic hypersomnia are rare, chronic sleep disorders that can debilitate patients' cognitive function, social functioning and health-related quality of life. They are primarily characterized by excessive daytime sleepiness (EDS) and often require long-term (even life-long) treatment to reduce symptoms and improve functioning. Sodium oxybate (Xyrem^®) is an effective treatment option for cataplexy and EDS in patients with narcolepsy; however, its high sodium content may put patients at higher risk of increased blood pressure and cardiovascular disease. To reduce the excessive sodium intake associated with long-term therapy, lower-sodium oxybate (Xywav^®), a new oxybate formulation with 92% less sodium content, has been developed. In the USA, it is approved for the treatment of cataplexy or EDS in adults and children aged ≥ 7 years with narcolepsy, and is the first drug approved for the treatment of idiopathic hypersomnia in adults. In pivotal phase 3 trials, following dose titration and optimization periods, participants randomized to discontinue lower-sodium oxybate and take placebo showed significant worsening in narcolepsy- and idiopathic hypersomnia-related symptoms, as well as health-related quality of life outcomes compared with participants randomized to continue lower-sodium oxybate. Lower-sodium oxybate is generally well tolerated, with its safety profile similar to that of sodium oxybate. Lower-sodium oxybate is a valuable treatment option for children and adults with narcolepsy and adults with idiopathic hypersomnia.