The FDA has approved Xywav (JZP-258), an oxybate product for treating both cataplexy and excessive daytime sleepiness in narcolepsy patients ages 7 and older, from Jazz Pharmaceuticals plc, of Dublin.
It is the first approved new treatment option for the indications in more than 15 years, and the company plans Xywav’s launch by year-end. In the meantime, Jazz will implement a risk evaluation and mitigation strategy for the treatment.
Jazz’s Xyrem (sodium oxybate) was the only available product approved to treat cataplexy and excessive daytime sleeping, in patients with narcolepsy ages 7 and older and is the standard of care for treating cataplexy. Xyrem is by far Jazz’s biggest seller, bringing in $1.64 billion, 75.9% of the company’s revenue, in 2019.
Xywav (calcium, magnesium, potassium and sodium oxybates) is a GABA B receptor agonist and contains 92% less sodium than Xyrem.
The approval was based on the global, double-blind, placebo-controlled, randomized-withdrawal, multicenter phase III trial of Xywav that enrolled 201 participants and randomized 134, which achieved primary and key secondary endpoints, demonstrating statistically significant differences in weekly number of cataplexy attacks (p<0.0001) and Epworth Sleepiness Scale scores (p<0.0001) compared to placebo.
Cataplexy, experienced by 70% of people with narcolepsy, is a type of sudden muscle weakness triggered by strong emotion, including laughter, surprise or anger.
Dublin-based Jazz submitted Xywav’s NDA in January and the FDA accepted it and granted a priority review in March. With the submission, the company redeemed a rare pediatric disease priority review voucher, which it acquired in 2018 from Spark Therapeutics Inc.
The approval came on the treatment’s PDUFA date of July 21.
Company stock (NASDAQ:JAZZ) had risen about 2% before the market opened Wednesday morning.
There is competition. On July 13, Avadel Pharmaceuticals plc, of Dublin, said the first patient was dosed in an open-label extension/switch study of FT-218 for treating excessive daytime sleepiness and cataplexy in patients with narcolepsy. In April, the company completed the REST-ON study, a pivotal, double-blind, randomized, placebo-controlled phase III trial assessing FT-218’s efficacy and safety in treating excessive daytime sleepiness and cataplexy in patients suffering from narcolepsy. Primary analysis of once-nightly FT-218 at 9 g demonstrated highly statistically significant (p<0.001), and clinically meaningful improvement across all three co-primary endpoints compared to placebo.
FT-218 uses Avadel's Micropump technology, a microparticulate system that allows the development of modified and/or controlled release of solid, oral dosage formulations of drugs. It's also part of London-based Glaxosmithkline plc's Coreg CR (carvedilol), an alpha/beta adrenergic-blocking agent approved in October 2006 and indicated for mild to severe chronic heart failure, left ventricular dysfunction following myocardial infarction in clinically stable patients, and hypertension.
Axsome Therapeutics Inc. said it will initiate phase III trials of AXS-12 for treating narcolepsy before the end of 2020. AXS-12’s phase II CONCERT study showed reduced cataplexy attacks and excessive daytime sleepiness compared to placebo in narcolepsy patients. AXS-12 is an oral, selective norepinephrine reuptake inhibitor and was granted orphan drug designation by the FDA.
U.S. claims data analysis, conducted by DRG, shows that stimulants and wakefulness-promoting agents are the most commonly prescribed drugs to treat newly diagnosed and recently treated narcolepsy patients. The majority of recently treated narcolepsy patients are on monotherapy. The most common combinations, when prescribed, include an antidepressant and Xyrem, DRG added.