Jazz Pharmaceuticals Submits Supplemental NDA for Xywav in Idiopathic Hypersomnia

Today, Jazz Pharmaceuticals announced it had submitted a supplemental new drug application (sNDA) to the FDA for Xywav (calcium, magnesium, potassium, and sodium oxybates) oral solution for the treatment of adults with idiopathic hypersomnia.

Pending approval, Xywav would be the only treatment in the United States for patients with the condition.

"This sNDA submission brings us one step closer to making this important treatment option available to patients living with idiopathic hypersomnia,” said Robert Iannone, MD, MSCE, executive vice president of research and development and chief medical officer for Jazz Pharmaceuticals.

The submission is based on positive top line results of Jazz Pharmaceuticals’ phase 3 multinational, double-blind, multicenter, placebo-controlled, randomized withdrawal study that showed Xywav, previously called JZP-258, met clinically meaningful improvements in its primary endpoint of Epworth Sleepiness Scale (ESS) and secondary endpoints of Patient Global Impression of Change (PGIc) and Idiopathic Hypersomnia Severity Scale (IHSS).

Notably, there were statistically significant worsenings in patients administered a placebo compared with Xywav for ESS (P < .0001), PGIc (P < .0001), and IHSS (P < .0001).

"Our purpose is to innovate to transform the lives of patients, and we are committed to collaborating with regulators, sleep experts, and patients to deepen our understanding of sleep disorders and the science around sleep medicine," said Iannone.

Already approved for the treatment of cataplexy or excessive daytime sleepiness (EDS) in patients 7 years and older with narcolepsy, Xywav received a Fast Track designation by the FDA in September 2020 for the treatment of idiopathic hypersomnia, which was then followed by a rolling submission granted by the FDA for the sNDA in December. 

Characterized by chronic and disabling EDS, the prevalence of idiopathic hypersomnia has risen by 32% from 2013 to 2016. A 14% increase in narcolepsy was seen during the same period.

Although insurance claims data in the United States indicates that more than 37,000 adult patients have diagnosed idiopathic hypersomnia, Diane Powell, MD, board chair and chief executive officer of the Hypersomnia Foundation, notes that people with the condition often live without an accurate diagnosis for a long time, with some never receiving the diagnosis at all.

“Meanwhile, they struggle to keep up with school, work, and relationships," said Powell.

If approved by the FDA, Jazz Pharmaceuticals plans to bring Xywav to market for patients with idiopathic hypersomnia in the fourth quarter of 2021. Speaking previously with The American Journal of Managed Care^®, Iannone said that although his organization does not have any other ongoing phase 3 trials with Xywav, they are continuing to consider additional research in the area of sleep and narcolepsy, as well as expanding into related areas of neuroscience, such as essential tremor.