August 12, 2021
The U.S. FDA has approved a new indication for Xywav® (calcium/magnesium/ potassium/sodium oxybates) oral solution, manufactured by Jazz Pharmaceuticals, to treat idiopathic hypersomnia (IH) in adults. Xywav is the first drug to receive FDA approval to treat IH. It was originally approved in 2020 to treat cataplexy or excessive daytime sleepiness in patients at least seven years of age who have been diagnosed with narcolepsy.
IH is a neurological disorder that causes chronic, excessive daytime sleepiness. It is diagnosed by ruling out other conditions or factors, such as sleep apnea and medication side effects, that could be causing symptoms. In addition to excessive daytime sleepiness, IH can also make it extremely difficult to wake from sleep, lead to sleep that is not restorative, and cause a mental fog that makes it difficult to carry out basic tasks when awake.
In a clinically study, patients treated with Xywav had statistically significant and clinically meaningful differences versus patients who received a placebo, as measured by the Epworth Sleepiness Scale score, the Patient Global Impression of Change, and the Idiopathic Hypersomnia Severity Scale.
Recommended dosing under the new indication offers a twice-a-night or once-a-night dosing schedule. For the twice-a-night schedule, the starting dose is up to 4.5g taken by mouth each night, divided into two doses. This dose is titrated in increments of up to 1.5g per night per week based on efficacy and tolerability, not to exceed a 9g total nightly dose. If using a once-nightly dosing schedule, Xywav should be started as a single nightly administration of up to 3g taken orally. The dose can be titrated in increments of up to 1.5g per night per week based on efficacy and tolerability, with the maximum dose not to exceed 6g per night.
A black box warning cautions that Xywav is a central nervous system depressant capable of causing respiratory depression, and that it carries a risk of abuse and misuse. Abuse or misuse of Xywav can lead to seizures, respiratory depression, decreased consciousness, coma, and death. The product is available only through a Risk Evaluation and Mitigation Strategy (REMS) program.