Positive top-line Phase III results for Xywav in hypersomnia

Shares of Ireland-incorporated Jazz Pharmaceuticals (Nasdaq: JAZZ) were up 6.2% at $152.28 in early trading today, after the company announced positive top-line results from the Phase III double-blind, multicenter, placebo-controlled, randomized withdrawal study evaluating the efficacy and safety of an investigational use of Xywav (calcium, magnesium, potassium, and sodium oxybates) oral solution in adult patients with idiopathic hypersomnia.

Patients entering the study had excessive daytime sleepiness typical of the idiopathic hypersomnia population. All patients were treated with Xywav during the open-label titration period and clinically-meaningful improvements in the Epworth Sleepiness Scale (ESS) were observed.

The primary endpoint of ESS and the key secondary endpoints of Patient Global Impression of Change (PGIc) and Idiopathic Hypersomnia Severity Scale (IHSS) were measured during the randomized withdrawal portion of the trial, which included 115 patients. Those who were administered Xywav showed clinically-meaningful maintenance of efficacy for ESS, PGIc and IHSS, and there were highly statistically-significant worsenings in patients administered placebo compared with Xywav for ESS (p-value <0.0001), PGIc (p-value <0.0001) and IHSS (p-value <0.0001).