Jazz Pharmaceuticals has announced that the Phase III trial of JZP-258 for the treatment of cataplexy and excessive daytime sleepiness (EDS) demonstrated highly statistically significant differences in the primary endpoint.
The global, double-blind, placebo-controlled, randomised-withdrawal, multi-centre Phase III study evaluated the efficacy and safety of JZP-258, a novel oxybate product candidate, to treat EDS in adult patients with narcolepsy.
It enrolled 201 patients and randomised 134 patients, comprising a heterogeneous patient population which included those who were treated with Xyrem earlier, naïve to Xyrem, and with or without other anti-cataplectic treatments.
The primary endpoint measured the change in the weekly number of cataplexy attacks and the key secondary endpoint of change in Epworth Sleepiness Scale (ESS) score with JZP-258 compared to placebo.
Patients in the study were randomised to either continue JZP-258 or receive placebo.
Those who were randomised to JZP-258 showed clinically meaningful maintenance of efficacy for cataplexy, as well as EDS, while a statistically significant worsening for both cataplexy and ESS endpoints was observed in the placebo group compared to JZP-258.
Jazz Pharmaceuticals Sleep and CNS Medicine senior vice-president Jed Black said: “Jazz is committed to developing new treatment options that serve unmet needs for patients living with sleep disorders, including JZP-258, a novel oxybate product candidate with 92% less sodium than sodium oxybate.
“We are deeply grateful to the patients and investigators who participated in this study, and we will meet with the FDA to discuss the Phase III results in narcolepsy and our NDA submission plans, with the goal of making JZP-258 available to narcolepsy patients.”
The company will include data from the completed Phase III study and interim data from the ongoing 24-week open-label, safety study in the planned submission of a New Drug Application (NDA) to the US Food and Drug Administration (FDA).
In November last year, Jazz enrolled the first patient in Phase III clinical trial to assess the efficacy and safety of JZP-258 for the treatment of idiopathic hypersomnia.