Testing two doses of a muscle relaxant for drowsiness in healthy adults
Official title: A Prospective, Randomized, Single-blind, Study to Assess Drowsiness, Cognition, Fall Risk, and Electroencephalographic (EEG) Dynamics After Oral Metaxalone Tablets 640 mg (M640) Versus Metaxalone 800 mg in Healthy Participants
Run by Primus Pharmaceuticals · NCT07801066 · Data updated 2026-11-12
This study tests two single doses of metaxalone in healthy adults to see how drowsiness and fall risk change when the drug is highest in the blood.
Quick facts
| Phase | Phase 4 |
|---|---|
| Study type | Interventional |
| Ages | 18 Years to 55 Years |
| Sex | All |
| Enrollment | 20 (estimated) |
| Sponsor | Primus Pharmaceuticals Industry-sponsored |
| Locations | 1 site (Columbus, Ohio) |
| Status | Recruiting |
| Started | October 15, 2026 |
| Main results expected | January 15, 2027 |
| Study ends | January 15, 2027 |
| Registry record updated | November 5, 2026 |
| Trial ID | NCT07801066 on ClinicalTrials.gov |
Is this trial a fit for you?
✓Likely a good fit
Healthy adults aged 18–55 who weigh at least 120 pounds and have no medical conditions affecting sleep, cognition, or cardiovascular status.
✕Probably not a fit
Individuals with sleep disorders, cognitive disorders, uncontrolled blood pressure or heart rate issues, or those who are pregnant or taking medications affecting sleep may not benefit.
A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.
What this trial studies
Healthy adults will take one dose after a meal, undergo drowsiness and fall-risk testing at peak blood levels, and have EEG monitoring during testing. After a one-week washout, they will receive the second dose with the same testing sequence for comparison. The trial is a randomized, crossover-like comparison of two dosages, conducted at a single site.
Why it matters
Potential benefit: Participants may gain a better understanding of how the two doses affect drowsiness and fall risk, which could inform safer use of the medication.
How similar studies have gone: Previous investigations have examined dose-related drowsiness with muscle relaxants, supporting the feasibility of this approach.
Who can join: the full rules
Show full inclusion / exclusion criteria
Inclusion Criteria: * Healthy adults aged 18 to 55 years old * Weigh at least 120 pounds * Medically healthy * Able to sign and date informed consent form Exclusion Criteria: * Current use of any medications known to affect the sleep-wake cycle * Sleep disorder diagnosis * Positive urine test for drugs * Known history of alcohol use disorder * Having a history of cognitive disorders, depression, schizophrenia, panic disorder, or dementia * Having difficulty eating high fat meal * Participants who are pregnant, nursing or intending to become pregnant during the period of study. * Blood Pressure \> 160/110 or \<90/50 mmHg. * Heart Rate \>100 or \< 50/ beats per minute. * Having a history of seizure disorder or epilepsy.
Where it's running
-
AMR Clinical - Columbus
Columbus, Ohio, United States Recruiting
Study contacts
- Study coordinator: Project Manager
- Email: mshahbandar@primusrx.com
- Phone: 480-483-1410
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How to take part
- Review the eligibility criteria above with your treating physician.
- Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
- Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.