Lemborexant in Delayed Sleep Phase Syndrome
Trial Parameters
Brief Summary
The purpose of the study is to evaluate whether Lemborexant is more effective than placebo in shortening sleep onset latency in patients with delayed sleep phase syndrome (both type 1 and type 2). This will be tracked using sleep logs as well as actigraphy. In this 2-year study, the investigators will examine if Lemborexant administered 5-10 mg nightly taken at desired bedtime (at least 2 hours prior to self-reported sleep onset habitual time) can improve the symptoms of Delayed Sleep Phase Syndrome.
Eligibility Criteria
Inclusion Criteria: \- Participants will be required to be 18 years of age or older and have delayed sleep phase syndrome (DSPS). Questionnaires will be used to identify potential confounders and to confirm a potential diagnosis of DSPS based on ICSD3 criteria: a) Sleep is delayed by two hours or more beyond what is considered an acceptable or conventional bedtime for the subject (their desired bedtime). b) Subjects not able to fall asleep if trying to sleep before the later bedtime; c) This is interfering with their wishes/having a social impact. Concomitant medications will be allowed, though dosages will be required to remain fixed throughout participation in the study. The participant also needs to be willing and able to comply with all aspects of the protocol. Exclusion Criteria: * Clinically significant depression (PHQ-9 score of 10 or more), anxiety disorder (GAD- 7 score of 10 or more), substance use disorder, any other sleep disorder, or any medical disorder/therapy that could