Grant: Canada Postdoctoral Research Award (CPRA) program

Depression affects nearly 8% of Canadians each year, and over 85% of these individuals experience insomnia. Even after successful antidepressant treatment, more than half continue to struggle with sleep, which can worsen mood, energy, concentration, and overall quality of life. Current insomnia medications, such as benzodiazepines and Z-drugs, offer only short-term relief and carry risks of daytime drowsiness, memory problems, and dependence, leaving many-especially older adults-without safe, effective options. Lemborexant is a newly approved drug in Canada that targets the brain's orexin system, regulating wakefulness. It has demonstrated efficacy in improving sleep with fewer side effects and no known dependence. However, its effectiveness for insomnia that persists after depression treatment remains unknown. This pilot study, led by me as principal investigator, will be the first to test lemborexant in adults with adequately treated depression who continue to experience insomnia. Thirty participants will be randomly assigned to receive lemborexant or placebo for six weeks. Sleep improvement will be measured using the Insomnia Severity Index, and participants will be interviewed about their experiences, including effectiveness, safety, and barriers to participation. Recruitment targets, retention, and feasibility of follow-up procedures will be assessed to inform a larger trial. By conducting this study, we aim to identify a safer, non-dependent treatment that improves sleep, daytime functioning, and quality of life for adults recovering from depression. Participant interviews will provide insights into patient priorities and inform recruitment strategies, guiding age-, sex-, and gender-sensitive trial design. Results will directly inform clinicians, patients, and health authorities, supporting evidence-based care for residual insomnia. This work has the potential to improve outcomes for Canadians and contribute to global strategies managing insomnia in depression