A Phase 1/2 interventional study of Lemborexant 10mg and Placebo in Cannabis Use Disorder, sponsored by University of Calgary. Not yet recruiting at 1 site in Canada. Open to participants aged 18 Years to 65 Years. Per ClinicalTrials.gov, last updated 2026-09-22.
Sponsored by University of Calgary · Phase 1/2, Interventional, and Treatment
The goal of this clinical trial is to investigate the use of Lemborexant as a treatment for moderate to severe Cannabis Use Disorder (CUD). The main questions it aims to answer are:
Researchers will compare 10mg Lemborexant to placebo.
Participants will:
521 studies on the registry are indexed under Behavior, Addictive; 124 are open to participants now.
This study's planned enrollment of 28 is below the median of 62 across 399 interventional studies indexed under Behavior, Addictive.
Browse Behavior, Addictive studies →University of Calgary is the lead sponsor of 703 studies on the registry; 196 are open to participants now.
Of its 10 completed or terminated interventional studies of FDA-regulated products, 2 (20%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Drug: Lemborexant 10mg · Behavioral: Brief Behavioural Intervention
Drug: Placebo · Behavioral: Brief Behavioural Intervention
21 days of 10mg Lemborexant, taken nightly.
21 days of visually-matched placebo, taken nightly.
Participants will receive a brief behavioural intervention at the in-person study visits aimed at helping participants identify ways to reduce their cannabis use.
Feasibility: Participant Recruitment Rate
Measured by assessing the number of participants recruited into the study (28 anticipated) throughout study duration (24 months estimated).
Time frame: From first participant in until study closure (estimated 24 months).
Feasibility: Participant Retention Percentage
Measuring the number of participants who complete the study compared to the total number of study participants, displayed as a percentage (%).
Time frame: From first participant in until study closure (estimated 24 months).
Tolerability: Participant Drop-Out Rates
Measured by comparing frequency of participant drop-outs in treatment versus control groups.
Time frame: From first participant in until study closure (estimated 24 months).
Safety: Adverse Event Frequency
Measured by comparing the frequency of adverse events in the treatment versus control groups.
Time frame: Participants will have the opportunity to report adverse events daily during the study treatment phase (days 0-21).
Safety: MADRS-S Depression
Measured using the Montgomery-Åsberg Depression Rating Scale - Self Report (MADRS-S) which scores depression from 0-54, with higher scores indicating worse depression.
Time frame: The MADRS-S will be administered on days 0, 7, 14, and 21 during the study treatment phase (days 0-21).
Safety: C-SSRS Suicidality
Measured using the Columbia Suicide Severity Rating Scale (C-SSRS), which uses Yes/No answers to categorize into No, Low, Moderate, or High risk.
Time frame: The C-SSRS will be administered on days 0, 7, 14, and 21 during the study treatment phase (days 0-21).
Sleep (Objective): Actigraphy Data
Participants will wear actigraphy watches continuously during the study treatment phase in order to measure objective sleep data.
Time frame: Measured continuously during the study treatment phase (days 0-21).
Sleep (Subjective): PSQI
The Pittsburgh Sleep Quality Index (PSQI) will be used as a subjective measure of sleep. Scores can range from 0-21, with higher scores indicating worse sleep.
Time frame: The PSQI will be administered at pre-screening and day 21.
Sleep (Subjective): LSEQ
The Leeds Sleep Evaluation Questionnaire (LSEQ) is a subjective measure of sleep which uses a 100mm visual analog scale, with lower scores being indicative of worse sleep.
Time frame: Participants will take the LSEQ on days 0, 7, 14, and 21 throughout the study treatment phase (days 0-21).
Sleep (Subjective): Daily Diaries CSD
Participants will complete daily diaries each morning via REDCap, which will include questions regarding their prior night's sleep from the Consensus Sleep Diary (CSD).
Time frame: Daily diaries will be completed daily during the study treatment phase (days 0-21).
Cannabis Use (Objective): Plasma THC and Metabolites
Blood draws will be performed in order to measure plasma THC and metabolite levels as an objective measure of cannabis use.
Time frame: Blood draws will occur on days 0 and 21 during the study treatment phase (days 0-21).
Cannabis Use (Subjective): EC-TLFB
The Enhanced Cannabis Timeline Followback (EC-TLFB) will be administered during study visits in order to subjectively assess participant cannabis use.
Time frame: The EC-TLFB will be administered on days 0, 7, 14, and 21 during the study treatment phase (days 0-21).
Cannabis Use (Subjective): Daily Diaries
Participants will complete daily diaries each morning via REDCap, which will include questions regarding their cannabis use from the day prior.
Time frame: Daily diaries will be completed daily during the study treatment phase (days 0-21).
Cannabis Use (Subjective): DFAQ-CU
The Daily Sessions, Frequency, Age of Onset, and Quantity of Cannabis Use (DFAQ-CU) measures multiple aspects of cannabis consumption in participants, and will be used as part of our subjective cannabis use measurements.
Time frame: The DFAQ-CU will be administered on days 0 and 21 during the study treatment phase (days 0-21).
Cannabis Withdrawal: Daily Diaries Modified MWC
The Marijuana Withdrawal Checklist (MWC) asks participants to score their severity of 22 marijuana withdrawal symptoms. On a scale of 0-66, higher scores indicate worse marijuana withdrawal symptoms. We have adapted the MWC to ask participants about their prior day's symptoms, and included it as part of the REDCap daily diaries.
Time frame: Daily diaries will be completed daily during the study treatment phase (days 0-21).
Cognition: Divided Attention
Divided attention cognitive tasks assess participants' ability to focus on one task versus multiple tasks, with less difference between the them indicating better cognitive outcomes.
Time frame: Divided attention cognitive tasks will be administered on days 0 and 21 during the study treatment phase (days 0-21).
Cognition: Working Memory
Working memory will be assessed via N-back and word memory tasks, with better scores being indicative of better cognitive function.
Time frame: N-back and word memory tasks will be administered on days 0 and 21 during the study treatment phase (days 0-21).
Cognition: Planning via Tower of London
The Tower of London task assesses participant planning ability, with higher scores indicative of better planning and cognition.
Time frame: Tower of London will be administered on days 0 and 21 during the study treatment phase (days 0-21).
Follow-Up Outcome (Safety): Adverse Event Frequency
Measured by comparing the frequency of adverse events in the treatment versus control groups.
Time frame: Participants will have the opportunity to report adverse events daily during the study follow-up phase (days 22-35).
Follow-Up Outcome (Safety): Depression
Measured using the Montgomery-Åsberg Depression Rating Scale - Self Report (MADRS-S) which scores depression from 0-54, with higher scores indicating worse depression.
Time frame: The MADRS-S will be administered on day 35 during the study follow-up phase (days 22-35).
Follow-Up Outcome (Safety): Suicidality
Measured using the Columbia Suicide Severity Rating Scale (C-SSRS), which uses Yes/No answers to categorize into No, Low, Moderate, or High risk.
Time frame: The C-SSRS will be administered on day 35 during the study follow-up phase (days 22-35).
Follow-Up Outcome (Sleep): LSEQ
The Leeds Sleep Evaluation Questionnaire (LSEQ) is a subjective measure of sleep which uses a 100mm visual analog scale, with lower scores being indicative of worse sleep.
Time frame: Participants will take the LSEQ on day 35 during the study follow-up phase (days 22-35).
Follow-Up Outcome (Sleep): Daily Diaries CSD
Participants will complete daily diaries each morning via REDCap, which will include questions regarding their prior night's sleep from the Consensus Sleep Diary (CSD).
Time frame: Daily diaries will be completed daily during the study follow-up phase (days 22-35).
Follow-Up Outcome (Cannabis Use): EC-TLFB
The Enhanced Cannabis Timeline Followback (EC-TLFB) will be administered during study visits in order to subjectively assess participant cannabis use.
Time frame: The EC-TLFB will be administered on day 35 during the study follow-up phase (days 22-35).
Follow-Up Outcome (Cannabis Use): Daily Diaries
Participants will complete daily diaries each morning via REDCap, which will include questions regarding their cannabis use from the day prior.
Time frame: Daily diaries will be completed daily during the study follow-up phase (days 22-35).
Follow-Up Outcome (Withdrawal): Daily Diaries Modified MWC
The Marijuana Withdrawal Checklist (MWC) asks participants to score their severity of 22 marijuana withdrawal symptoms. On a scale of 0-66, higher scores indicate worse marijuana withdrawal symptoms. We have adapted the MWC to ask participants about their prior day's symptoms, and included it in the REDCap daily diaries.
Time frame: The modified MWC will be completed daily during the study follow-up phase (days 22-35).
Plan to share: No
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Studies of the drug tested here: Lemborexant