Effect of sodium oxybate (SXB), modafinil and combination on disrupted nighttime sleep in narcolepsy

Abstract

Introduction Disrupted nighttime sleep (DNS) affects most narcolepsy patients. An expert consensus on DNS identified frequent shifts to lighter sleep and awakenings and reported poor sleep quality as important measures of DNS. In this study, data from a randomized trial retrospectively analyzed effects of three common narcolepsy treatments on DNS. Materials and methods Patients with narcolepsy ( N = 231) were randomized to placebo (PBO), 9 g SXB/nightly, 200–600 mg/day modafinil or a SXB/modafinil combination. Polysomnograms (PSGs) and sleep quality from the Pittsburgh Sleep Quality Index (PSQI) question 6 were obtained at baseline and 8 weeks. Analysis was performed for 155 patients with evaluable sleep stage and 201 patients with evaluable PSQI data. Results SXB given alone, or in combination with modafinil, decreased shifts from S2, 3, 4 or REM to 1/Wake significantly more than placebo ( P ⩽ 0.015). Median change from baseline was −1.5 (range −37 to 37), −13.0 (−74 to 20), 0.0 (−53 to 44), −11.5 (−58 to 45) shifts in the PBO, SXB, modafinil and SXB + modafinil groups, respectively. Sleep quality showed greater improvement for SXB and SXB + modafinil versus placebo ( P ⩽ 0.034). For the population treated with SXB (given alone or in combination with modafinil), the most common adverse events (⩾5%) were nausea, dizziness, headache, vomiting, nasopharyngitis, somnolence, tremor, and paraesthesia. Conclusion In this retrospective analysis, SXB appeared to improve PSG and patient-reported measures of DNS in narcolepsy. Acknowledgement This study was sponsored by Jazz Pharmaceuticals, Inc.