Jazz Pharmaceuticals plc announced that the first patient has been enrolled in a Phase 3 clinical study evaluating JZP-258, an investigational oxybate product candidate with 90% less sodium content than Xyrem (sodium oxybate) oral solution, as a potential treatment for cataplexy and excessive daytime sleepiness (EDS) in adult narcolepsy patients. The clinical study will be conducted across approximately 60 centers in the European Union and the United States.

“We believe that reducing sodium intake in narcolepsy patients is a clinically meaningful goal as patients with narcolepsy are at risk for high sodium intake-related consequences, including hypertension and other cardiovascular diseases,” says Karen Smith, MD, PhD, global head of research and development and chief medical officer of Jazz Pharmaceuticals, in a release. “The initiation of patient enrollment in this study reinforces our commitment to the narcolepsy community and is an important step in our efforts to provide patients with potentially improved therapeutic options to treat their narcolepsy.”

The Phase 3 study is a double-blind, placebo-controlled, randomized-withdrawal, multicenter study evaluating the efficacy and safety of JZP-258 for the treatment of cataplexy and EDS in adult patients with narcolepsy (ClinicalTrials.gov identifier: NCT03030599). The study is expected to enroll approximately 185 patients in order to randomize approximately 130 patients.