THC for Cannabis Use

(HIGH-CAP Trial)

Overseen By Ziva Cooper, PhD

Age: 18 - 65

Sex: Any

Trial Phase: Phase 1

Sponsor: University of California, Los Angeles

Must not be taking: Prescription analgesics, others

Disqualifiers: Substance use disorder, Psychiatric illness, Pregnancy, others

Compensation: Varies

Number of Visits: Unknown

Duration: 3 hours per session

30 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores the effects of regular cannabis use and the impact of a short break from it. The study tests three groups: one with no THC (the active component of cannabis), one with a low dose, and one with a high dose (high-potency cannabis). Individuals who smoke cannabis nearly every day and are not currently seeking to quit may be suitable candidates for this trial. As a Phase 1 trial, this research aims to understand how cannabis affects the body, providing participants an opportunity to contribute to foundational knowledge.

Will I have to stop taking my current medications?

The trial requires that participants do not use medical cannabis, prescription painkillers, or any medications that might affect the study results. If you're on such medications, you may need to stop taking them to join the trial.

Is there any evidence suggesting that this trial's treatments are likely to be safe?

Research has shown that low-dose THC (50 mg) can have positive effects, but it might also cause some health issues. Frequent or heavy cannabis use may lead to mental health problems, such as anxiety or mood changes.

High-dose THC (100 mg) carries its own risks. Studies have found that cannabis with high THC levels can increase the risk of psychosis, a condition where someone loses touch with reality. Daily use of high-potency THC can heighten this risk. Some reports suggest that long-term use of high-dose THC might harm brain health and raise the risk of mental health disorders.

In this early phase of clinical trials, researchers are testing these treatments for safety. While not all risks will be known at this stage, the trial aims to assess how well participants can handle these doses. Prospective participants should understand both the potential benefits and risks. ^{1 2 3 4 5}

Why are researchers excited about this trial's treatments?

Researchers are excited about using high potency cannabis for cannabis use because it takes a novel approach to addressing cannabis addiction. Unlike traditional treatments that might focus on behavioral therapy or substitute medications, this trial explores the impact of varying THC dosages directly—ranging from no THC to high doses. The goal is to understand how different THC levels affect cannabis use, which could lead to more personalized and effective strategies for managing cannabis dependence. By investigating both low and high THC doses, this approach could provide insights into optimal dosing for reducing cannabis use or helping individuals manage withdrawal symptoms.

What evidence suggests that this trial's treatments could be effective for cannabis use?

Research has shown that small amounts of THC, such as 10 mg taken several times a day, can reduce withdrawal symptoms and cravings for cannabis. In this trial, participants will receive either a placebo, a low dose of THC (50 mg), or a high dose of THC (100 mg). Low-dose THC might assist those aiming to reduce cannabis use. However, high doses of THC carry a greater risk of mental health problems and addiction. While strong cannabis may have quick effects, it may not be the best choice for long-term health. Overall, low-dose THC appears more effective and safer for managing cannabis use. ^{3 6 7 8 9}

Are You a Good Fit for This Trial?

This trial is for adults aged 21-55 who smoke cannabis nearly every day but aren't looking to treat their usage. They should be able to do all study tasks, have a BMI of 18.5 - 34kg/m2, and use contraception if needed. Pregnant or breastfeeding women can't join.

Inclusion Criteria

I smoke cannabis almost every day.

I am a man or a woman not pregnant or breastfeeding, aged 21-55.

I can participate in all required study activities.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive smoked cannabis with varying THC doses and placebo to assess acute effects

3 hours per session

Multiple sessions (in-person)

Abstinence

Participants undergo a brief period of abstinence to assess changes in cannabis effects

1-2 weeks

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• High Potency Cannabis

Trial Overview The study is testing the effects of smoked cannabis by comparing high dose THC, low dose THC, and placebo in participants during normal use and after a short break from using cannabis.

How Is the Trial Designed?

Group I: Low dose THC Active Control 1 Intervention

50 mg THC

Group II: High dose THC Active Control 1 Intervention

100 mg THC

Group III: Placebo Comparator: Placebo Placebo Group 1 Intervention

0 mg THC

Who Is Running the Clinical Trial?

University of California, Los Angeles

Lead Sponsor

Trials

1,594

Recruited

10,430,000+

California Department of Cannabis Control (DCC)

Collaborator

Trials

1

Recruited

30+

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC8655458/

Cannabis use and cannabis use Disorder - PMC Approximately 17.0% of weekly and 19.0% of daily cannabis smokers met the criteria for cannabis dependence. In addition, in a longitudinal study almost 1 in 19 ...

2. psychiatryonline.org psychiatryonline.org/doi/10.1176/appi.ajp.20240269

High-Potency Cannabis Use and Health: A Systematic ... Thirteen studies assessed the relationship between higher-potency cannabis use and at least one nonacute mental health outcome, including ...

3. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC7027478/

Heavy cannabis use, dependence and the brain: a clinical ... Impairments may depend on THC dose and heavy cannabis users are generally only affected at higher dosages 4, 5. Long‐term effects are less clear.

4. leg.colorado.gov leg.colorado.gov/sites/default/files/images/mj_presentation_for_mhdcjs_committee_july_21_2022.pdf

Negative Impacts of High Potency THC on Community & ... Collectively these results indicate that cannabis may reduce PTSD symptoms in the short-term but may not be an effective long-term remedy for ...

5. masscannabiscontrol.com masscannabiscontrol.com/document/high-tetrahydrocannabinol-thc-cannabis-and-effects-on-the-human-body-more-research-needed-october-2021/

High Tetrahydrocannabinol (THC) Cannabis and Effects on ... Given the evidence of CBD's attenuating effects on some THC-related outcomes, it is advisable to use cannabis containing high CBD:THC ratios.

6. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC6312155/

The Problem with the Current High Potency THC Marijuana ... They found that use of high potency THC >15% resulted in a three times increased risk of psychosis, and if the use was daily there was a five times increased ...

7. medicine.yale.edu medicine.yale.edu/news-article/not-your-grandmothers-marijuana-rising-thc-concentrations-in-cannabis-can-pose-devastating-health-risks/

Marijuana: Rising THC Concentrations in Cannabis Can Pose ... Emerging studies suggest that cannabis use leads to an increased risk of reporting psychotic symptoms. A 2022 study, for instance, found a ...

8. nm.org nm.org/healthbeat/healthy-tips/how-cannabis-use-impacts-long-term-health

How Cannabis Use Impacts Long-Term Health Long-term cannabis use can affect brain development, lung health, and may increase risk of psychiatric disorders, and loss of IQ.

9. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC10632847/

Health Effects of High-Concentration Cannabis Products Fifty-four studies (12%) examined a direct association between cannabis concentrates and a health outcome, whereas 189 (42%) examined a direct association ...