Simulated driving performance in healthy adults after night-time administration of 20 mg tasimelteon

An impairment in next day driving performance has been reported for almost every drug currently United States Food and Drug Administration (FDA) approved for improvement of sleep in chronic and transient insomnia. Tasimelteon, a melatonin receptor agonist, demonstrated significant improvements in night-time sleep, daytime naps, and sleep timing in non-24-hr sleep-wake disorder (Non-24) by entraining these patients to a 24-hr day as measured by melatonin and cortisol rhythms. Given this new mechanism of action of entraining the biological clock, we conducted a study to evaluate the potential effect tasimelteon may have on the ability to operate a motor vehicle. The study was conducted in 48 healthy adult subjects using a randomised, double-blind, placebo and active (zopiclone 7.5 mg) controlled study with a 3-period cross-over design. Driving performance was assessed by measuring standard deviation of lateral position (SDLP) using the validated Cognitive Research Corporation Driving Simulator-MiniSim. The difference in least square mean SDLP for tasimelteon was 1.22 cm reflecting a non-significant increase in SDLP change from placebo (p = .1119). In contrast, treatment with the active control, zopiclone 7.5 mg, was associated with a meaningful and significant increase in SDLP, change from placebo for zopiclone was 4.14 cm (p < .0001). The lack of clinically meaningful and statistically significant finding with tasimelteon was further supported by the symmetry analysis, which showed the distribution of within-subject differences between tasimelteon and placebo was symmetric about zero. At the FDA-approved 20 mg dose to treat Non-24, tasimelteon did not impair next-day driving performance compared to placebo in adult healthy volunteers.