344 Daridorexant Improves Total Sleep Time (TST) in Insomnia Patients Without Altering the Proportion of Sleep Stages

Abstract

Introduction: Daridorexant, a new dual orexin receptor antagonist, improved sleep parameters and daytime functioning in two pivotal Phase 3 trials in patients with insomnia (Trial-1, NCT03545191; Trial- 2, NCT03575104); polysomnography data were collected at multiple timepoints from >1,800 patients. We report the effects of daridorexant on TST and sleep stages from both trials. Methods: Eligible patients with insomnia (according to DSM-5) were randomized (1:1:1) in Trial-1 (N=930) to daridorexant 25mg, 50mg, or placebo and in Trial-2 (N=924) to daridorexant 10mg, 25mg, or placebo. Oral treatment was administered each night during a 3-month double-blind treatment period. Assessment of TST and sleep stages (non-rapid eye movement [NREM, N]1, N2, N3, REM), measured by polysomnography in sleep laboratory, was performed on two consecutive nights during single-blind placebo run-in (baseline) and Months 1 and 3 (M1 and M3) of double-blind treatment. Change from baseline in TST and sleep stages were exploratory endpoints in both trials. Data for M3 (mean ± standard deviation) are presented as change from baseline. Results: Daridorexant dose-dependently increased TST(minutes) from baseline to M3, more than placebo, in Trial-1 (25mg, 55±56; 50mg, 61±53; placebo, 40±56) and Trial-2 (10mg, 37±57; 25mg, 50±53; placebo, 35±56). In both trials, sleep stage proportions were preserved from baseline to M3, with no relevant changes in any group. Baseline time spent in each sleep stage (% of TST) was consistent across groups in both trials (range across treatment groups in both trials: N1:11-13; N2:55-57; N3:11-14; REM:19-20). In Trial-1 (25mg/50mg/placebo), the change from baseline to M3 in % of TST spent in N1(-0.3±4.7/-0.2±5/0.1±5), N2(2±8/1±7/1±7), N3(-2±6/- 2±6/-2±6), and REM(1±6/1±5/1±5) was low and numerically similar across treatments. In Trial-2, the change from baseline to M3 in % of TST spent in each sleep stage was consistent with Trial-1, with no effect of dose. Mean changes from baseline (% of TST) for each sleep stage appeared to be independent from increasing TST. Data for 25mg were consistent between trials. Conclusion: Daridorexant at any dose, and each more than placebo, increased TST in a dose-dependent manner without affecting the proportion of all sleep stages in patients with insomnia.