CompletedEarly Phase 1

Assessing the Pharmacokinetics and Drug Interaction Liability of Kratom, an Opioid-like Natural Product

United States15 participantsStarted 2019-10-09

Plain-language summary

Kratom is a botanical natural product that has opioid-like effects. Kratom is commonly used to self-treat withdrawal symptoms associated with opioid addiction, as well as pain. Kratom products include pills, extracts, and powders, most of which contain two primary psychoactive constituents: mitragynine and 7-hydroxymitragynine. Preliminary data from the investigator's laboratory has shown that these two constituents and extracts made from commercially available kratom products are strong inhibitors of the drug metabolizing enzymes cytochrome P450 (CYP) 2D6 and CYP3A4. These enzymes are responsible for metabolizing more than 50% of marketed drugs, including several opioids, benzodiazepines, and antidepressants. Thus, co-consumption of kratom products with drugs metabolized by CYP2D6 and CYP3A4 could increase the risk of serious adverse effects. The effects of a well-characterized kratom product on CYP2D6 and CYP3A4 activity will be assessed in healthy volunteers using a 'cocktail' approach consisting of the validated probe drugs dextromethorphan and midazolam. Results will (1) provide useful information regarding risks associated with co-consuming kratom with opioids and other CYP2D6 and CYP3A4 drug substrates and (2) inform the design of future kratom-drug interactions studies.

Who can participate

Age range

18 Years – 55 Years

Sex

ALL

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Inclusion Criteria: * Not taking any medications (prescription and non-prescription) or dietary/herbal supplements known to alter the pharmacokinetics of either study drug or kratom constituents * Willing to abstain from consuming dietary/herbal supplements, including kratom, and citrus juices for several weeks * Willing to abstain from consuming caffeinated beverages or other caffeine-containing products the evening before and morning of the first day of a study arm * Willing to abstain from consuming any alcoholic beverages for one day prior to any study day, during the 14-hour inpatient days, and for the 5 and/or 1 outpatient visit(s) following 14-hour visit * Willing to use an acceptable method of contraception that does not include oral contraceptive pills or patches (such as abstinence, copper IUD, condom) * Have the time to participate * Are non-naïve kratom users (intermittent users who are not trying to quit but willing to abstain for several weeks) * Carry a CYP2D6 genotype designated as having an intermediate, extensive, or ultra-extensive metabolizer phenotype * Written informed consent (and assent when applicable) obtained from subject or subject's legal representative and ability for the subject to comply with the requirements of the study Exclusion Criteria: * Men and women under the age of 18 or over the age of 55 * Unwilling to abstain from kratom for several weeks * Any current major illness or chronic illness such as (but not limited to) kidney disease, …

Questions worth asking your doctor

Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.

1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?

Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.

Questions for the trial coordinator

The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.

1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?

A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.

What they're measuring

Midazolam Area Under the Concentration vs. Time Curve (AUC)

Timeframe: 0, 0.25, 0.5, 1, 1.5, 2, 3, 4, 6, 8,12, 24, 48, 72 , 96, 120, and 144 hours

Trial details

NCT IDNCT04392011

SponsorWashington State University

Sponsor typeOTHER

Study typeINTERVENTIONAL

Primary completion2021-08-31

Results submitted2022-09-07

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