Cannabinoid Interactions for Knee Osteoarthritis Pain
This study is looking at how daily treatment with Tetrahydrocannabinol (THC), Cannabidiol (CBD), or a combination of both affects pain from knee osteoarthritis. Researchers want to see if CBD helps reduce inflammation, if THC changes how the brain processes pain, and if both together do both. You might be able to join if you are 21 to 75 years old, can read and speak English, and have been diagnosed with chronic moderate to severe knee pain from osteoarthritis for at least six months. The study aims to enroll 200 participants. Success will be measured by changes in brain activity related to pain and levels of an inflammatory marker called IL-6. The current recruitment status is unclear.
- Study design
- This is an interventional study where participants will be randomly assigned to receive either a placebo, Cannabidiol (CBD), or Tetrahydrocannabinol (THC). The study is blinded, meaning you won't know which treatment you are receiving.
- What's involved
- You will have a screening period and visit for up to 30 days before treatment starts. If you qualify, you will take one of the study drugs daily for a period, with clinical pain assessed multiple times.
- Compensation
- Not stated in the trial record.
- Follow-up
- Measurements will be taken at Day 15 and approximately Day 99 of treatment to assess changes in brain connectivity and inflammatory markers.
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NCT04992624
Cannabinoid Interactions With Central and Peripheral Pain Mechanisms in Osteoarthritis of the Knee
Recruiting
PHASE2Ages 21–75InterventionalSteven E Harte, PhDInvestigator-initiated
~200 participants
Updated 2025-09-02 on ClinicalTrials.gov
What's tested:PlaceboCannabidiol (CBD)Tetrahydrocannabinol (Marinol® or generic equivalent (e.g., dronabinol)
At a glance
Recruiting sites
1 of 1 listed site is recruiting right now
RecruitingSuspended, closed, or not yet open
What they're measuring
Default mode network (DMN) to insula connectivity via functional connectivity magnetic resonance imaging (fcMRI)
Measured over Day 15, and approximately day 99 of treatment
+1 more outcome measured
Conditions
Where it's being run
1 sites across 1 statesMichigan1
Study leadership
- Steve Harte, PhD · PRINCIPAL_INVESTIGATOR · University of Michigan
Who to contact
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Do you actually qualify for this trial?
Add a private profile and we'll compare every criterion below against your situation — and tell you which ones are met, uncertain, or excluding.
Eligibility criteria
Inclusion
Ability to read and speak English to allow for written informed consent, phenotyping, and patient-reported outcomes measures
Willingness to participate in a drug intervention trial
Diagnosis of osteoarthritis (OA) of the knee by a medical provider (confirmed by checking medical records)
Chronic knee pain, defined as moderate to severe knee pain for ≥ 6-month duration
No use of cannabis or CBD in the past in the month prior to study enrollment as per self-report
Fibromyalgia (FM) Survey Criteria score available. The questionnaire will be assessed by the research team for scoring. We will recruit enough patients to satisfy the spectrum of FM scores in four quartiles based on our previously existing data. Once a quartile is filled (approximately 40 patients enrolled), then we will not include more people from that quartile.
Self-reported normal visual acuity or correctable (with corrective lenses- glasses or contacts) to at least 20/40 for reading instructions in the MRI and visual sensitivity testing
No contraindications to magnetic resonance imaging (MRI) (for example (e.g.), metal implants)
Able to lie still on their back for 1-1.5 hours during MRI
Willingness to refrain from pain medications such as non-steroidal anti-inflammatory drugs (NSAIDs) and acetaminophen for 12 hours prior to neuroimaging and Quantitative Sensory Testing (QST)
Willingness to refrain from alcohol and nicotine before QST and neuroimaging (alcohol and nicotine consumption is allowed after testing is completed)
Willingness to refrain from physical activity or exercise that would cause significant muscle and/or joint soreness for 48 hours prior to testing (routine exercise or activity that does not lead to soreness is acceptable)
Willingness to maintain a stable treatment regimen for chronic knee OA pain during the clinical trial (e.g., not initiating a new course of physical therapy)
No use of adjunctive pain medications or stable chronic daily use of adjunctive pain medications (excluding opioids)
Willingness to avoid grapefruit juice or food products for the duration of the study;
Females of reproductive potential must agree to use acceptable birth control from the screening visit and until the completion study drug administration. Sexually active male participants and/or their female partners must agree to use effective contraception during study drug treatment of the male participant. Male participants may also agree not to donate sperm during study drug treatment
Exclusion
Individuals who are actively applying for or in litigation for compensation or disability and other aspects associated with potential secondary gain per self-report
Inability to provide written informed consent
Previous total knee arthroplasty
Planned total knee arthroplasty within the time frame of the study
Severe physical impairment (e.g., blindness, deafness, paraplegia)
Co-morbid medical conditions that may significantly impair physical functional status (e.g., history of non-skin malignancy, or autoimmune disorder)
Use of cannabis or CBD in the past month per self-report and/or drug screen
Current opioid use (excepting tramadol) per self-report and/or drug screen
Current valproate, clobazam, or warfarin use per self-report or medical records
Current use of moderate or strong inhibitors of cytochrome p450 (CYP) enzymes CYP3A4 and CYP2C19, strong inducers of CYP3A4 or CYP2C19, moderate or strong inhibitors/inducers of CYP2C9, and narrow therapeutic index drugs (e.g., cyclosporine, amphotericin B). Participants will also not be allowed to start using these drugs during the study period if they wish to stay in the study
Self-reported allergies to sesame oil or cannabis/cannabinoids
Self-reported medical or psychiatric conditions that in the judgment of study personnel would preclude participation in this study (e.g., schizophrenia, malignancy, psychosis, suicidal ideation, history of substance abuse; note that stable anxiety and depression are not exclusions)
Pregnant or nursing
Liver failure
Self-reported liver cirrhosis
Active diagnosis or current symptoms of hepatitis by self-report
Self-reported uncontrolled diabetes
Blood pressure at screening above 180 systolic and/or 120 diastolic
Resting heart rate at screening less than 50 beats per minute (bpm) or greater than 100 bpm;
Elevated liver enzymes and bilirubin (measured via blood test at screening):
Serum total bilirubin ≥ 2.5 milligrams per deciliter (mg/dL); or,
Alanine Aminotransferase (ALT) or Aspartate Aminotransferase (AST) ≥ 3x upper limit normal (ULN); or,
Alkaline phosphatase ≥ 2 times ULN
Severe cardiovascular disease (examples: history of myocardial infarction, unstable angina, severe coronary artery disease, congestive heart failure, or severe valvular abnormalities) that is self-reported by patient or by medical record
Severe claustrophobia precluding MRI
Unable to fit in or lie comfortably in MRI
Diagnosed peripheral neuropathy
Diagnosed or self-reported epilepsy or history of seizures
Current head injury or history of head injury (e.g., traumatic brain injury)
Any impairment, activity, behavior, or situation that in the judgment of the study team would prevent satisfactory completion of the study protocol
What this trial measures
- Default mode network (DMN) to insula connectivity via functional connectivity magnetic resonance imaging (fcMRI)Day 15, and approximately day 99 of treatment
Functional connectivity difference maps of insula to DMN connectivity using Independent Component Analysis and seed based connectivity. A reduction in the Z-score as a result of treatment will serve as the primary outcome measure.
- Change in pre-post measurements of inflammatory marker IL-6.Day 15, and approximately day 99 of treatment
Serum IL-6