On-the-road driving performance the morning after bedtime administration of lemborexant in healthy adult and elderly volunteers

Study Objectives: To assess potential effects of lemborexant on next-morning driving performance in adult and elderly healthy volunteers. Methods: Randomized, double-blind, double-dummy, placebo and active-controlled, four period incomplete crossover study in 48 healthy volunteers (22 females), 23-78 years old. Participants were treated at bedtime for 8 consecutive nights with 2 of 3 dose levels of lemborexant (2.5, 5, or 10 mg), zopiclone 7.5 mg (on the first and last night with placebo on intervening nights), or placebo. Driving performance was assessed in the morning on day 2 and 9 using a standardized highway driving test in normal traffic, measuring standard deviation of lateral position (SDLP). Drug-placebo differences in SDLP > 2.4 cm were considered to reflect clinically meaningful driving impairment. Results: Mean drug-placebo differences in SDLP following lemborexant 2.5, 5, and 10 mg on day 2 and 9 were 0.74 cm or less. The upper bound of the 95% confidence intervals (CIs) for lemborexant treatment groups were all below 2.4 cm and the 95% CIs included zero, indicating that the effects were neither clinically meaningful nor statistically significant. Symmetry analysis further supported the lack of clinically meaningful impairment with lemborexant. Conclusions: When assessed starting ~9 h after lemborexant administration at bedtime the previous night, there was no statistically significant or clinically meaningful effect on driving performance in healthy adults and elderly, as assessed by either mean differences in SDLP relative to placebo or symmetry analysis. In this study, lemborexant at doses up to 10 mg was well-tolerated.