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A Study of Suvorexant (MK-4305) for the Treatment of Insomnia Disorder in Participants With Opioid Use Disorder (MK-4305-098)
NCT06655883 · View on ClinicalTrials.gov ↗
Study Summary
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.
Conditions Studied
Interventions
- DRUG Placebo
- DRUG Suvorexant
Study Locations (10)
Texas
- Adams Clinical Dallas ( Site 2007) — DeSoto
- Memorial Hermann Village ( Site 2001) — Houston
Connecticut
- Yale University School of Medicine ( Site 1003) — New Haven
Georgia
- CenExel iResearch, LLC ( Site 2010) — Savannah
Maryland
- Johns Hopkins University ( Site 1001) — Baltimore
New Jersey
- Hassman Research Institute Marlton Site ( Site 2005) — Marlton
Oklahoma
- The Rivus Wellness & Research Institute ( Site 2014) — Oklahoma City
Pennsylvania
- Penn Medicine University of Pennsylvania Health System- Center for Studies of Addiction ( Site 1006) — Philadelphia
Rhode Island
- Butler Hospital ( Site 1002) — Providence
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 300 participants |
| Start Date | 2025-10-09 |
| Est. Completion | 2027-06-24 |
| Phase | Phase 3 |
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Full Details on ClinicalTrials.gov ↗What the Registry Record Tells You About NCT06655883
The ClinicalTrials.gov registry entry for NCT06655883 describes a study currently listed as recruiting. It is categorized as Phase 3, which is the standard way researchers label where a study sits along the investigational pathway from early safety work through later efficacy and post-marketing evaluation. The registered enrollment target is 300 participants, a figure that helps gauge the scale of data the investigators plan to collect. The listed sponsor is Merck Sharp & Dohme, which has 741 total studies on file at ClinicalTrials.gov, and sponsors are the parties responsible for study design, oversight, and regulatory filings.
The record links to 1 condition, with Insomnia appearing as the primary indexed condition, and to 2 interventions — of which Placebo is the first listed. Interventions can include drugs, devices, procedures, behavioral programs, or observational arms, and each is tracked as a separate registry field so that downstream queries can filter accurately. When a trial lists multiple interventions, it usually reflects a multi-arm design or a comparison protocol rather than a single treatment being tested in isolation. The brief summary published in the registry is the clearest source of protocol intent and should be read before drawing conclusions from any sidebar tags.
Geographic footprint matters for practical reasons: NCT06655883 reports 10 study locations spanning 9 distinct geographic areas — top geographies include Texas, Connecticut, Georgia. A larger site network tends to correlate with broader recruitment capacity, but it does not imply anything about study quality, and site-level enrollment status can diverge from the overall registry status shown above. Every data point on this page comes from the public ClinicalTrials.gov dataset and is reproduced here for reference only; it is not a medical recommendation, an endorsement of the sponsor, or an invitation to enroll. Verify current status, eligibility criteria, and contact details directly at ClinicalTrials.gov, and discuss any participation decision with your own healthcare provider.
Frequently Asked Questions
What is clinical trial NCT06655883 about?
NCT06655883 is a clinical study titled "A Study of Suvorexant (MK-4305) for the Treatment of Insomnia Disorder in Participants With Opioid Use Disorder (MK-4305-098)". 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 ...
What is the current status of trial NCT06655883?
This trial is currently recruiting. It is a Phase 3 study. The enrollment target is 300 participants. The study started on 2025-10-09. Estimated completion is 2027-06-24.
What conditions does trial NCT06655883 study?
This clinical trial studies the following conditions: Insomnia. These conditions were identified from the trial registry and reflect the primary focus areas of the research.
What interventions are being tested in trial NCT06655883?
The interventions under investigation include: Placebo (DRUG), Suvorexant (DRUG). Each intervention is being evaluated for safety and efficacy as part of this clinical study.
Who is sponsoring clinical trial NCT06655883?
This trial is sponsored by Merck Sharp & Dohme, which has 741 total clinical trials registered on ClinicalTrials.gov. The sponsor is responsible for the study's design, funding, and regulatory compliance.
Where is trial NCT06655883 being conducted?
This trial has 10 study locations across Connecticut, Georgia, Maryland, New Jersey, Oklahoma. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
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