An Early Phase 1 interventional study of Cannabidiol in the form of hemp and Clopidogrel in Interaction, sponsored by Washington State University. Recruiting at 1 site in United States. Open to participants aged 21 Years to 64 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-06-04.
Sponsored by Washington State University · Early Phase 1, Interventional, and Basic science
The goal of this clinical trial is to determine how two different doses of cannabidiol (CBD), given as a hemp product, change the blood concentrations of the drug clopidogrel in the body. Results will be used to help design future studies and to assist healthcare providers in informing their patients about the safe use of CBD.
The popularity of cannabis products has grown exponentially over the past decade as several states continue to decriminalize or legalize recreational and/or medicinal use. Cannabis contains >500 phytoconstituents, including >100 cannabinoids. The most well-studied cannabinoids are tetrahydrocannabinol (THC) and cannabidiol (CBD). Although both are psychoactive, THC produces the characteristic "high," while CBD does not. CBD is available as a prescription drug (Epidiolex®) to treat seizure disorders. Hemp, a popular CBD-containing botanical product, is defined as containing \<0.3% THC. Hemp was federally legalized in the United States in 2018 following passage of the Farm Bill. Since passage of that bill, hemp and other CBD-containing products have become widely available over the counter. As such, hemp/CBD products have become top-selling botanicals, with sales projected to reach nearly $4.5 billion by 2024. Common uses include self-treatment for pain, anxiety, and sleep disorders.
Despite increasing use of cannabis products, the pharmacokinetic interaction potential with pharmaceutical medications remains understudied. Previous pharmacokinetic studies have yielded convincing evidence that CBD significantly inhibits the activity of the drug metabolizing enzyme cytochrome P450 (CYP) 2C19. Despite the valuable information generated by these and numerous other studies, several unanswered questions about CBD-containing products remain:
The primary objective of the proposed study is to evaluate the effects of a well-characterized, widely used hemp product on the pharmacokinetics of the commonly prescribed CYP2C19 substrate clopidogrel (Plavix®) in healthy adult participants who are confirmed to be CYP2C19 normal, rapid, or ultra-rapid metabolizers. Results could be used to inform a future study design involving elderly people, which is a population of interest. Results could also be used to guide healthcare providers in helping their patients make informed decisions about the safe use of hemp
Washington State University is the lead sponsor of 83 studies on the registry; 16 are open to participants now.
Of its 7 completed or terminated interventional studies of FDA-regulated products, 4 (57%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will be administered a single oral dose (75 mg) of clopidogrel. Blood and urine will be collected for 24 hours.
Drug: Clopidogrel
Participants will self-administer a single low dose of hemp (30 mg CBD) as an oral softgel at home daily for 5 consecutive days. On day 6, participants will return to the research setting, where they will be administered a single low dose of hemp (30 mg CBD) and a single oral dose of clopidogrel (75 mg). Blood will be collected for 72 hours and urine will be collected for 24 hours.
Drug: Cannabidiol in the form of hemp · Drug: Clopidogrel
Participants will repeat the Arm 2 procedures using a higher dose of hemp (240 mg CBD)
Drug: Cannabidiol in the form of hemp · Drug: Clopidogrel
Cannabidiol (30 mg) in the form of an orally administered hemp oil softgel
Also known as: CBD
75 mg oral clopidogrel
Also known as: Plavix
AUC ratio of clopidogrel active metabolite
Ratio of the area under the plasma concentration vs. time curve of the active metabolite of clopidogrel in the presence to absence of hemp
Time frame: 0-24 hours
Cannabidiol AUC
Area under the plasma concentration vs. time curve of cannabidiol
Time frame: 0-72 hours
AUC of cannabidiol metabolites
Area under the plasma concentration vs. time curve of cannabidiol metabolites
Time frame: 0-72 hours
Plan to share: Yes — IPD used in the results publication
No publications or documents are linked to this record.
Started Jun 2024 (actual). Primary completion is estimated for Aug 2027, 38 months after the start.
How these figures are worked out, and which studies are left out of them.
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Studies of the drug tested here: Clopidogrel
Washington State University