A Study of Mitragynine Formulations for Exercise-Induced Muscle Soreness in Healthy Adults

NCT07809282 | Completed Phase 2

• 1 other identifier: T01-24-01-T0047
• Study Type: interventional
• Target: 100
• Locations: 1 country
• Sites: 1

Brief Summary

This Phase II randomized, double-blind, placebo-controlled study will evaluate the safety, tolerability, and physical dependence potential of mitragynine-containing formulations after 28 days of use and assess their effects on exercise-induced muscle soreness in healthy adults. One hundred participants will be randomized in a 1:1:1:1 ratio to SpecioTea 20 mg, SpecioTea 40 mg, MitraPlex 20 mg, or placebo. Participants will complete an exercise challenge to induce delayed-onset muscle soreness (DOMS), undergo efficacy assessments at 24 and 48 hours post-exercise, and continue daily dosing for approximately 28 days followed by withdrawal and safety assessments.

Conditions

Delayed Onset Muscle Soreness (DOMS); Exercise-Induced Muscle Soreness

Keywords

Mitragynine; Delayed Onset Muscle Soreness (DOMS); Exercise-Induced Muscle Soreness

Outcome Measures

Primary Outcomes (16)

• Safety and Tolerability After 28 Days of Use (Vitals)

  Heart Rate (bpm)

  Baseline through Visit 7 (approximately 45 days) with primary safety assessment after 28 ± 2 days of dosing.

• Safety and Tolerability After 28 Days of Use (Vitals)

  Blood Pressure (mmHg)

  Baseline through Visit 7 (approximately 45 days) with primary safety assessment after 28 ± 2 days of dosing.

• To assess the effect of each TP intervention on changes in creatinine compared to each other and to a placebo

  Change in concentration of creatinine

  Change from baseline to 1 hour, 24 hours, and 48 hours post-exercise

• To assess the effect of each TP intervention on changes in myoglobin compared to each other and to a placebo

  Change in concentration of myoglobin

  Change from baseline to 1 hour, 24 hours, and 48 hours post-exercise

• To assess the effect of each TP intervention on changes in lactose dehydrogenase (LDH) compared to each other and to a placebo

  Change in concentration of LDH

  Change from baseline to 1 hour, 24 hours, and 48 hours post-exercise

• To assess the effect of each TP intervention on changes in CK compared to each other and to a placebo

  Change in concentration of creatine kinase (CK)

  Change from baseline to 1 hour, 24 hours, and 48 hours post-exercise

• To assess the effect of each TP intervention on muscle strength after intense exercise compared to each other and to a placebo

  Change in the maximum weight moved

  Change from baseline to 24 hours and 48 hours post-exercise

• To assess the effect of each TP intervention on reducing joint stiffness after intense exercise compared to each other and to a placebo

  Change in the magnitude of joint range of motion (degrees)

  Change from baseline to 24 hours and 48 hours post-exercise

• To assess the efficacy of each TP intervention on reducing exercise-induced muscle soreness at 24 h and 48 h post-exercise compared to each other and to a placebo

  Change in Visual Analog Scale score. Participants will draw a vertical line on 100 mm scale that represents the current intensity of their pain where left end of the scale is representative of "no soreness at all" and the right end of the scale is representative of "extreme soreness". The intensity of pain will be considered to be the distance (in mm) of the participant's mark from the left-hand side of the scale.

  Change from baseline to 24 hours and to 48 hours post-exercise

• Safety and Tolerability After 28 Days of Use (Anthropometrics)

  Assessment of Body weight (kg)

  Baseline through Visit 7 (approximately 45 days) with primary safety assessment after 28 ± 2 days of dosing.

• Safety and Tolerability After 28 Days of Use (Anthropometrics)

  Assessment of BMI (kg/m2)

  Baseline through Visit 7 (approximately 45 days) with primary safety assessment after 28 ± 2 days of dosing.

• Safety and Tolerability After 28 Days of Use (Laboratory Blood Tests)

  Blood samples will be collected to assess hematology parameters (hemoglobin, hematocrit, red blood cell \[RBC\], red blood cell distribution width \[RDW\], RBC indices \[mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), MCH concentration (MCHC)\], white blood cells \[WBC\] with differential \[abs\], platelet count, mean platelet volume \[MPV\]).

  Baseline through Visit 7 (approximately 45 days) with primary safety assessment after 28 ± 2 days of dosing.

• Safety and Tolerability After 28 Days of Use (Laboratory Blood Tests)

  Change from baseline in clinical chemistry laboratory parameters. Blood samples will be collected to assess clinical chemistry parameters including urea, creatinine, total bilirubin, alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), random serum glucose, albumin, globulin, total protein, sodium, potassium, estimated glomerular filtration rate (eGFR), and chloride. Each laboratory parameter will be evaluated and reported separately according to its standard unit of measurement, with change from baseline summarized for each parameter.

  Baseline through Visit 7 (approximately 45 days) with primary safety assessment after 28 ± 2 days of dosing.

• Safety and Tolerability After 28 Days of Use (Adverse Events)

  Reports of AEs

  Baseline through Visit 7 (approximately 45 days) with primary safety assessment after 28 ± 2 days of dosing.

• Safety and Tolerability After 28 Days of Use (SOWS)

  Changes in Subjective Opiate Withdrawal Scale (SOWS) scores for grading opioid withdrawal symptoms. A SOWS total score of 1-10 is considered mild, 11-20 moderate and 21-30 severe. On both scales, greater scores correspond to increased perception of any of the symptoms.

  Baseline through Visit 7 (approximately 45 days) with primary safety assessment after 28 ± 2 days of dosing.

• Safety and Tolerability After 28 Days of Use (COWS)

  Changes in Clinical Opiate Withdrawal Scale (COWS) scores which is the summed score used to determine the stage or severity of opiate withdrawal and assess the level of physical dependence on opioids (score of below 5 = no withdrawal; 5-12 = mild; 13-24 = moderate; 25-36 = moderately severe; more than 36 = severe withdrawal).

  Baseline through Visit 7 (approximately 45 days) with primary safety assessment after 28 ± 2 days of dosing.

Study Arms (4)

SpecioTea 20 mg

EXPERIMENTAL

Participants receive 4 capsules daily containing a total of 20 mg mitragynine (2 active capsules plus 2 placebo capsules).

Dietary Supplement: SpecioTea

SpecioTea 40 mg

EXPERIMENTAL

Participants receive 4 active capsules daily containing a total of 40 mg mitragynine.

Dietary Supplement: SpecioTea

MitraPlex 20 mg

EXPERIMENTAL

Participants receive 4 active capsules daily containing a total of 20 mg mitragynine.

Dietary Supplement: MitraPlex

Placebo

PLACEBO COMPARATOR

Participants receive 4 placebo capsules daily.

Other: Placebo

Interventions

SpecioTea DIETARY_SUPPLEMENT

SpecioTea is a dried aqueous kratom leaf extract administered orally in capsule form. Participants receive 4 capsules once daily. The study evaluates two dosage levels: 20 mg mitragynine daily (2 active capsules plus 2 placebo capsules) and 40 mg mitragynine daily (4 active capsules).

SpecioTea 20 mg; SpecioTea 40 mg

MitraPlex DIETARY_SUPPLEMENT

MitraPlex is a dried ethanolic/water kratom leaf extract administered orally in capsule form. Participants receive 4 active capsules once daily providing a total daily dose of 20 mg mitragynine.

MitraPlex 20 mg

Placebo OTHER

Matching placebo capsules administered orally. Participants receive 4 placebo capsules once daily. Placebo capsules are visually indistinguishable from active study product capsules to maintain blinding.

Placebo

Eligibility Criteria

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

You may qualify if:

• Healthy males and females who are 18 to 55 years of age (inclusive).
• In good general health as deemed by the investigator and are able to consume the study product.
• Have a BMI between 18.0 to 34.9 kg/m2 (inclusive).
• Naïve to kratom use or occasional kratom use (i.e., have not used kratom more than once within 28 days prior to baseline \[Visit 2\]).
• Non-smokers (including nicotine vaping) and have not used nicotine-containing products (patches, gums, etc.) for \> 3 months prior to baseline (Visit Note: Non-smoker is defined as someone who does not habitually/regularly use products containing nicotine.
• Appropriate for exercise as determined by the PAR-Q at screening (Visit 1A).
• Demonstrate DOMS 48 h post-exercise by having a VAS ≥ 40 mm after completion of the exercise challenge at Visit 1A.
• Agree to follow the restrictions on concomitant treatments.
• Agree to follow the restrictions on lifestyle (especially regarding physical activity).
• Agree to use acceptable contraceptive methods.
• Have suitable veins for repeated venipuncture as deemed by the investigator.
• Have maintained consistent dietary habits (including medication and supplement intake), exercise and lifestyle habits for the last 3 months before screening (Visit 1A) and agree to maintain them throughout the study (unless required per the restrictions).
• Willing and able to agree to the requirements of this study, be willing to give voluntary consent, be able to understand and read the questionnaires, and carry out all study-related procedures.

You may not qualify if:

• Individuals who are lactating, planning to become pregnant during the study, or pregnancy as confirmed by a positive urine pregnancy test at screening Visit 1A or Visit 2.
• Have a positive drug screen for any of the compounds listed as confirmed at screening Visit 1A or Visit 2.
• Have a known sensitivity, intolerability, or allergy to any of the study products or their excipients, or the rescue medication, NARCAN® (naloxone).
• Current COVID-19 infections, or currently have the post COVID-19 condition as defined by World Health Organization (WHO) (i.e., individuals with a history of probable or confirmed SARS-CoV-2 infection, usually 3 months from the onset of COVID-19 with symptoms that last for at least 2 months and cannot be explained by an alternative diagnosis).
• Have exercised regularly (generally \> 150 cumulative minutes per week) for 6 months prior to screening (Visit 1A) and/or Visit 2.
• Have engaged in regular lower extremity fitness activities (e.g., running, cycling, soccer or hockey) for more than two times per week for ≥ 2 consecutive weeks in the past 6 months prior to screening (Visit 1A) and/or Visit 2.
• Had lower body surgery (e.g., hips, knees, ankles, etc.) within 6 months prior to screening (Visit 1A) and/or planned lower body surgery during the study.
• History of any lower body injury \[e.g., partial anterior cruciate ligament (ACL) tear, broken or fractured bone, major sprain\] within 6 months prior to screening (Visit 1A) and/or during the study.
• Have Type I/Type II diabetes or thyroid disease.
• Have uncontrolled or controlled high blood pressure (≥140 systolic or ≥90 diastolic mmHg) at screening.
• Have medical condition(s) known to interfere with absorption, distribution, metabolism, or excretion of the study product (e.g., Crohn's disease, short bowel, acute or chronic pancreatitis, or pancreatic insufficiency).
• Have a history of heart/cardiovascular disease, immune disorders and/or immunocompromised (i.e., HIV/AIDS).
• Have active asthma or have experienced an asthma attack in the last 5 years.
• Have a history of neurological disorders such as epilepsy.
• Have hepatic or renal dysfunction as evidenced by ALT and/or AST being ≥ 2 times the upper limit of normal (ULN), serum creatinine or urea value ≥ 1.5 times the ULN, or other clinically significant abnormal clinical laboratory value per investigator discretion.

Sponsors & Collaborators

• Traditional Naturals Research Inc.: lead
• Nutrasource Pharmaceutical and Nutraceutical Services, Inc.: collaborator

Study Sites (1)

Apex Trials

Guelph, Ontario - on, N1G 0B4, Canada

Location

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: August 28, 2026
• First Posted: September 9, 2026
• Study Start: February 5, 2025
• Primary Completion: October 22, 2025
• Study Completion: October 22, 2025
• Last Updated: September 9, 2026

Record last verified: 2026-09

Data Sharing

• IPD Sharing: Will not share

Locations

CA (1)