NCT06157177 · Primus Pharmaceuticals
Efficacy of M640 in Acute Lumbosacral Musculoskeletal Conditions.
What this study is about
The goal of this clinical trial is to learn if a modification to metaxalone 640 mg can reduce low back and leg pain. The participants will be 18 to 80 years old, healthy with newly occurring back or leg pain. The main question aims to compare a group taking active treatment and a group taking a look-alike substance containing no active treatment.
View original scientific description
The goal of this clinical trial is to learn if a modification to metaxalone 640 mg can reduce low back and leg pain. The participants will be 18 to 80 years old, healthy with newly occurring back or leg pain. The main question aims to compare a group taking active treatment and a group taking a look-alike substance containing no active treatment.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- No clinically significant conditions impacting quality or quantity of pain
- Baseline Numeric Pain Scale ≥ 6
- Capable of answering text or email survey reminders
- Low back pain with or without sciatica
Exclusion criteria
- Current use of other skeletal relaxants
- Current use of other pain relievers
- Current use of cimetidine or monoamine oxidase inhibitors
Where
- Auburn, Alabama
- Valley Village, California
- Aventura, Florida
- Boca Raton, Florida
- Clearwater, Florida
- Coral Springs, Florida
- Jupiter, Florida
- Loxahatchee Groves, Florida
- Margate, Florida
- Miami, Florida
- Miami Beach, Florida
- Oldsmar, Florida
And 12 more locations — see the full list below.
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced May 12, 2026 · Source of record for eligibility and locations