FDA Approves Jazz Pharmaceuticals’ Cataplexy Drug

Rare Daily Staff 

The U.S. Food and Drug Administration has approved Jazz Pharmaceuticals’ drug Xywav oral solution for the treatment of oral solution for the treatment of cataplexy or excessive daytime sleepiness in patients 7 years of age and older with narcolepsy.

Narcolepsy is a chronic, debilitating, rare neurological disorder characterized by excessive daytime sleepiness and the inability to regulate sleep-wake cycles normally. It affects an estimated one in 2,000 people in the United States, with symptoms typically appearing in childhood. It is estimated that more than half of patients with narcolepsy have not been diagnosed. Studies have shown it may take 10 years or more for people with narcolepsy to receive a diagnosis.

Cataplexy is the most specific symptom of narcolepsy, and is the sudden, generally brief loss of muscle tone with retained consciousness. It is usually triggered by strong emotions, such as laughter, surprise, or anger. Although many emotions can potentially trigger cataplexy, those associated with mirth are usually the most potent. Cataplexy occurs in about 70 percent of people with narcolepsy. Complete collapse is not common with episodes usually involving only certain muscle groups, such as the arms and legs, the head and neck, or the face and jaw.

Xywav is the first FDA approved new treatment option indicated for both cataplexy and excessive daytime sleepiness in people living with narcolepsy in more than 15 years. It is an oxybate product—a mix of calcium, magnesium, potassium, and sodium oxybates—with a unique formulation resulting in 92 percent less sodium intake compared to Jazz’s Xyrem (sodium oxybate), the current standard of care treatment for narcolepsy.

“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 CEO of Jazz Pharmaceuticals.

The FDA approval of Xywav is based on a global phase 3 double-blind, placebo-controlled, randomized-withdrawal, multicenter study that demonstrated the efficacy and safety of Xywav in the treatment of cataplexy and excessive daytime sleepiness in patients with narcolepsy. In the study, which enrolled 201 patients, Xywav demonstrated highly statistically significant differences in the weekly number of cataplexy attacks and Epworth Sleepiness Scale scores compared to placebo.

Sodium oxybate carries warnings about its high sodium content. With the goal of establishing a new standard of care, Xywav was developed to provide people with narcolepsy an oxybate therapy with lower sodium, and does not carry warnings about sodium content.

Xywav does have a Boxed Warning, though, as a central nervous system depressant, and for its potential for abuse and misuse. Because of the risks of CNS depression and abuse and misuse, Xywav is available only through a restricted program under a REMS program. Most common adverse reactions in adults were headache, nausea, dizziness, decreased appetite, parasomnia, diarrhea, hyperhidrosis, anxiety and vomiting.

Jazz plans to launch Xywav by the end of the year following Risk Evaluation and Mitigation Strategy (REMS) implementation.