Study to Assess Drowsiness, Cognition, Fall Risk After Metaxalone 640 mg and Metaxalone 800 mg

NCT06348303 | Completed Phase 4 FDA Drug

• 1 other identifier: PMMD-01
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

Every participant will receive Metaxalone in two (2) stages, one week after the other. A single dose of each Metaxalone dose will be taken one (1) time after a high fat meal which must be eaten within 30 minutes. Every participant will be given written tests to measure drowsiness, reaction time and thinking process and will also be asked to take walking tests to assess fall risk. Participation in this study will last approximately 2-4 weeks.

Conditions

Healthy Participants

Outcome Measures

Primary Outcomes (3)

• Percentage of participants unable to maintain Tandem Stand Position for more than 10 seconds (position 3 of the 4-Stage Balance Test).

  Validated 4-Stage Balance Test after completion of an FDA standardized high-fat meal. Place one foot in front of the other, heel touching toes.

  Baseline, Visit 2 dosing (Day 1), Visit 3 dosing (Day 8)

• Change from baseline of gait during a stopwatch timed, stand, and walk activity from a seated position along a 30 foot path

  Timed Up and Go with Triaxial Accelerometry

  Baseline, Visit 2 dosing (Day 1), Visit 3 dosing (Day 8)

• Change from baseline of correct number of steps taken on a fixed 4 inch wide, 9 feet long path

  Tandem Walk Test

  Baseline, Visit 2 dosing (Day 1), Visit 3 dosing (Day 8)

Secondary Outcomes (4)

• Change from baseline of participants' subjective report of drowsiness on a 10-point scale

  Baseline, Visit 2 dosing (Day 1), Visit 3 dosing (Day 8)

• Change from baseline of reaction to stimulus by computer generated visual prompts measured in milliseconds

  Baseline, Visit 2 dosing (Day 1), Visit 3 dosing (Day 8)

• Change from baseline of participants' reasoning ability to recognize differences in six (6) computer generated shapes for 30 minutes

  Baseline, Visit 2 dosing (Day 1), Visit 3 dosing (Day 8)

• The number of product related adverse events experienced by participants from Visit 2 through Visit 4

  Visit 2 dosing (Day 1, Visit 3 dosing (Day 8), Visit 4 End of Study (Day 15)

Study Arms (2)

Active 640 mg

ACTIVE COMPARATOR

Metaxalone (M640) 640 mg tablet, a single-dose at visit 2 of 4 visits.

Drug: Metaxalone m640 mg oral tablet

Active 800 mg

ACTIVE COMPARATOR

Metaxalone 800 mg tablet, a single-dose at Visit 3 of 4 visits.

Drug: Metaxalone 800 mg oral tablet

Interventions

Metaxalone m640 mg oral tablet DRUG

Metaxalone partially micronized 640 mg tablet

Also known as: m640

Active 640 mg

Metaxalone 800 mg oral tablet DRUG

Metaxalone non-micronized 800 mg oral tablet

Also known as: Skelaxin

Active 800 mg

Eligibility Criteria

• Age: 18 Years - 55 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Weigh at least 120 pounds at Screening
• Medically healthy with no clinically significant medical co-morbidities impact endpoints

You may not qualify if:

• Current use of any medications known to affect sleep-wake cycle.
• Known sleep disorder.
• Current use of cimetidine.
• Current use of a monoamine oxidase Inhibitor (MAOI), selective serotonin reuptake inhibitor (SSRI), selective norepinephrine reuptake inhibitor (SNRI), 5- hydroxytryptamine (5-HT) agonist or any drug that has the potential to affect the serotonergic neurotransmitter system (e.g. mirtazapine, trazodone, tramadol).
• Positive urine test for amphetamines, barbiturates, cocaine, opiates, benzodiazepines, or cannabinoids.
• Participants taking skeletal muscle relaxants or sedative hypnotics.
• Participants with gastrointestinal disease affecting absorption.
• Participants with severe hepatic or renal impairment.

Sponsors & Collaborators

• Primus Pharmaceuticals: lead
• ClinOhio Research Services, LLC: collaborator

Study Sites (1)

ClinOhio Research Institute

Columbus, Ohio, 43213, United States

Location

MeSH Terms

Interventions

metaxalone; Tablets

Intervention Hierarchy (Ancestors)

Dosage Forms; Pharmaceutical Preparations

Study Officials

• J Lukban, DO

  Primus Pharmaceuticals, Inc.

  STUDY DIRECTOR

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: NON RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Masking Details: Single mask of participants. Participants will be prevented from knowing product dose.
• Purpose: PREVENTION
• Intervention Model: CROSSOVER
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Model Details: Each participant will be enrolled to two (2), single dose, study treatment arms in a crossover design. The treatments will occur consecutively with seven (7) days separating days of dosing.

Study Record Dates

• First Submitted: March 30, 2024
• First Posted: April 4, 2024
• Study Start: May 16, 2024
• Primary Completion: September 5, 2024
• Study Completion: October 30, 2024
• Last Updated: August 7, 2025

Record last verified: 2025-08

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)