Jazz Pharmaceuticals Completes Submission of Supplemental New Drug Application for Xywav™ (calcium, magnesium, potassium, and sodium oxybates) Oral Solution for Idiopathic Hypersomnia

Jazz Pharmaceuticals plc (Nasdaq: JAZZ) today announced the completion of the rolling submission for the supplemental New Drug Application (sNDA) to the U.S. Food and Drug Administration (FDA) seeking marketing approval for Xywav™ (calcium, magnesium, potassium, and sodium oxybates) oral solution for the treatment of adult patients with idiopathic hypersomnia. If approved, Xywav will be the first and only approved treatment in the U.S. for adults with idiopathic hypersomnia. 

Xywav received Fast Track designation by the FDA in September 2020 for the treatment of idiopathic hypersomnia. Jazz was granted rolling submission by FDA for this sNDA in December 2020, permitting the submission of portions of the proposed application as they were completed.

"This sNDA submission brings us one step closer to making this important treatment option available to patients living with idiopathic hypersomnia. As a long-standing leader in sleep medicine, Jazz continues to invest in developing innovative treatments for patients with significant unmet needs. Jazz has spent over a decade researching the lower-sodium oxybate product, Xywav, in both narcolepsy and idiopathic hypersomnia," said Robert Iannone, M.D., M.S.C.E., executive vice president, research and development & chief medical officer of Jazz Pharmaceuticals. "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."

Jazz is planning to bring this treatment option to patients in the fourth quarter of this year, subject to FDA approval.

Idiopathic hypersomnia is a debilitating illness characterized by chronic and disabling excessive daytime sleepiness that can significantly affect social, school and occupational functioning.^1,2,3,4 Symptoms may also include prolonged, non-restorative nighttime sleep, long and unrefreshing naps and prolonged difficulty waking (sleep inertia), with frequent reentries into sleep, confusion, and irritability. Insurance claims data in the U.S. suggest that the diagnosed prevalence of idiopathic hypersomnia is more than 37,000 adult patients; however, many more are likely living with undiagnosed idiopathic hypersomnia.

"People with idiopathic hypersomnia often live without an accurate diagnosis for a long time — and some are never diagnosed at all. Meanwhile, they struggle to keep up with school, work and relationships," said Diane Powell, Board Chair and CEO, Hypersomnia Foundation. "We are encouraged by Jazz's progress and the possibilities for people living with idiopathic hypersomnia."

About the Phase 3 Study in Idiopathic Hypersomnia
The submission is based on a Phase 3 multi-national, double-blind, multicenter, placebo-controlled, randomized withdrawal study evaluating the efficacy and safety of Xywav for the investigational treatment of idiopathic hypersomnia in adult patients. The primary endpoint was the change in the Epworth Sleepiness Scale (ESS) score in the Xywav group compared to the placebo group over the randomized-withdrawal period. The key secondary endpoints were Patient Global Impression of Change (PGI-c) and change in Idiopathic Hypersomnia Severity Scale (IHSS) score. The IHSS is a recently developed, validated scale, and is a self-report measure of the severity, frequency, and consequences of the key symptoms of idiopathic hypersomnia.

The study design included a titration and optimization period of up to 14 weeks, a Xywav stable-dose period of two weeks, followed by a 1:1 randomization to either Xywav or placebo for 2 weeks. After the completion of the double-blind, placebo-controlled treatment period, patients entered a 24-week open-label safety extension period. More information about the study design is available at www.clinicaltrials.gov (identifier: NCT03533114).

The results of this study have been accepted for presentation at an upcoming medical meeting.