Daridorexant for Alzheimer Disease Prevention

Alzheimer's disease (AD) begins decades before symptoms with the accumulation of amyloid plaques and tau tangles, and interventions that slow or prevent this process could greatly reduce its impact. Dual orexin receptor antagonists (DORAs), drugs developed for insomnia, may help clear amyloid and tau, reduce neuroinflammation, and improve cognition through mechanisms that could be both related and unrelated to sleep quality. Early animal and human studies suggest that DORAs can alter biomarkers of Alzheimer's pathology making the orexin pathway modulation a promising strategy for Alzheimer's prevention. Daridorexant, one of the two DORAs available in Canada, stands out as a well-tolerated candidate for prevention due to its safety profile. We want to evaluate the potential of Daridorexant for prevention of AD in this single-site, double-blind, randomized (1:1), placebo-controlled trial evaluating 50 mg of daridorexant versus placebo over 12 months in 240 participants. The primary biological outcome is the change from baseline to 12 months in the plasma ratio of phosphorylated tau181 to unphosphorylated tau181 (p-tau181/np-tau181). Secondary outcomes include changes in additional plasma biomarkers, cognitive performance, sleep parameters, and safety measures.