A Study of Suvorexant (MK-4305) for the Treatment of Insomnia Disorder in Participants With Opioid Use Disorder (MK-4305-098)
Merck Sharp & Dohme LLC · NCT06655883
Opens the official ClinicalTrials.gov record, with the study team’s contacts. Bored Studies doesn’t enroll anyone.
Key facts
- Compensation
- Not posted. Ask the study team before screening.
- Who can join
- Ages 18–70 · All sexes
- Healthy volunteers
- Not accepted (a condition is required)
- Study type
- Interventional · Phase 3
- Target enrollment
- 300
- US sites recruiting
- 13
- Study start
- October 9, 2025
- Record last updated
- September 21, 2026
Status re-checked against ClinicalTrials.gov within the last 12 hours.
What the study is about
People with opioid use disorder (OUD) can have trouble falling or staying asleep. Researchers want to know if suvorexant will help people with OUD fall asleep and stay asleep. The goal of this study is to learn about the safety of suvorexant and how well people tolerate it. Researchers also want to learn if suvorexant helps people sleep longer compared to people who take placebo. A placebo looks like the study medicine but has no actual study medicine in it.
Being studied: Suvorexant; Placebo
Conditions: Insomnia
Eligibility criteria
Copied from the official record. The study team makes the final decision at screening.
Show full criteria
Inclusion Criteria
The main inclusion criteria include but are not limited to the following:
- Has a primary diagnosis of OUD according to Diagnostic and Statistical Manual of Mental Disorder, 5th Edition (DSM-5), and confirmed through the Mini International Neuropsychiatric Interview (MINI).
- Is on a verified, stable dose of medications for opioid use disorder (MOUD) treatment.
- Meets DSM-5 criteria for the diagnosis of Insomnia Disorder
- Has a regular bedtime between 8 PM (20:00) and 1 AM (01:00) and is willing to maintain it for the duration of the study.
- Has not used opioids for a period of at least 4 weeks before entering the study.
Exclusion Criteria
The main exclusion criteria include but are not limited to the following:
- Has current uncontrolled major co-morbid psychiatric illness including major depressive disorder, bipolar disorder, schizophrenia, or any psychiatric condition with psychotic features.
- Has current diagnosis or history within 5 years of any of the following: narcolepsy, sleep paralysis, severe periodic limb movement disorder, restless leg syndrome, cataplexy, circadian rhythm sleep disorder, parasomnia including nightmare disorder, sleep terror disorder, sleepwalking disorder, rapid eye movement (REM) behavior disorder, significant degree of sleep-related breathing disorder, excessive daytime sleepiness (EDS), or primary hypersomnia.
- Is at imminent risk of self-harm.
- Has a known history of stroke that may confound the diagnosis of insomnia.
- Has a clinically significant movement disorder such as akinesia.
- Has a history of hepatitis or live disease.
- Has habitual use of central nervous system (CNS)-depressants or stimulants that may be responsible for the participant's disturbed sleep.
- Has a history of malignancy, ≤3 years prior to start of study, with the exception of nonmelanoma skin cancer, prostate cancer or localized carcinoma in situ of the cervix.
- Has a history of hypersensitivity to more than 3 chemical classes of drugs, including prescription and over-the-counter medications.
- Has donated blood products or had phlebotomy within 8 weeks prior to start of study.
- Has a history of transmeridian travel within 2 weeks prior to start of study.
Recruiting US locations
Cenexel CNS ( Site 2012)
Garden Grove, CA 92845
Site contact: Study Coordinator · 866-787-4257
Yale University School of Medicine ( Site 1003)
New Haven, CT 06520
Site contact: Study Coordinator · 203-785-3627
Bradenton Research Center ( Site 2021)
Bradenton, FL 34205
Site contact: Study Coordinator · 941-708-0005
CenExel iResearch, LLC ( Site 2010)
Savannah, GA 31405
Site contact: Study Coordinator · 912-744-0800
Johns Hopkins University ( Site 1001)
Baltimore, MD 21224
Site contact: Study Coordinator · 443-216-9237
Hassman Research Institute Marlton Site ( Site 2005)
Marlton, NJ 08053
Site contact: Study Coordinator · 856-261-6420
The Rivus Wellness & Research Institute ( Site 2014)
Oklahoma City, OK 73112
Site contact: Study Coordinator · 405-607-2233
Penn Medicine University of Pennsylvania Health System- Center for Studies of Addiction ( Site 1006)
Philadelphia, PA 19104
Site contact: Study Coordinator · 215-222-3200
Butler Hospital ( Site 1002)
Providence, RI 02906
Site contact: Study Coordinator · 401-455-6440
Medical University of South Carolina ( Site 1005)
Charleston, SC 29403
Site contact: Study Coordinator · 843-792-4636
Adams Clinical Dallas ( Site 2007)
DeSoto, TX 75115
Site contact: Study Coordinator · 972-283-6286
Memorial Hermann Village ( Site 2001)
Houston, TX 77043
Site contact: Study Coordinator · 281-369-5765
VCU Institute for Drug and Alcohol Studies ( Site 1004)
Richmond, VA 23219
Site contact: Study Coordinator · 804-827-3784
Study contacts (from the official record)
- Toll Free Number · 1-888-577-8839 · Trialsites@msd.com
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