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Recruiting

NCT Number: NCT06859710

THC and CBD: A Controlled Human Study Probing a Harm Reduction Strategy

The purpose of this research is to assess the impact of CBD on the effects of THC.

Recruiting

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Key information

Age range

21 year–55 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 1

Primary location

About this study

Some evidence indicates that cannabidiol (CBD), a non-intoxicating cannabis component, might mitigate certain effects of THC. This study will examine possible roles for CBD in modulating THC's adverse and analgesic effects.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Male or non-pregnant and non-lactating females aged 21-55 years
  • Report cannabis use 1-7 days per week over the month prior to screening
  • Not currently seeking treatment for their cannabis use
  • History of inhaled cannabis use
  • Have a Body Mass Index from 18.5 - 34 kg/m2
  • Able to perform all study procedures
  • Must be using a contraceptive (hormonal or barrier methods)

Exclusion criteria

  • Meeting DSM-V criteria for severe Cannabis Use disorder (CUD) or any substance use disorder other than nicotine, caffeine, mild or moderate CUD
  • Evidence of severe psychiatric illness (e.g. mood or anxiety disorder with functional impairment or suicide risk, schizophrenia) judged by the study physician (and PI) to put the participant at greater risk of experiencing adverse events due to completion of study procedures, interfere with their ability to participate in the study, or their capacity to provide informed consent.
  • Report using other illicit drugs in the prior 4 weeks
  • Current pain
  • Pregnancy
  • Currently enrolled in another research protocol
  • Not using a contraceptive method (hormonal or barrier methods)
  • Insensitivity to the cold water stimulus of the Cold Pressor Test
  • Any disorders that might make cannabis administration hazardous as determined by evaluation physician after review of all medical assessments along with medical history.
  • Not able to speak and read English

Treatment and study plan

Placebo

Drug

Vaporized Placebo

Other names: Cannabis

THC

Drug

Vaporized THC (20 mg)

Other names: Cannabis

CBD 20 mg

Drug

Vaporized CBD (20 mg)

Other names: Cannabis

CBD 40 mg

Drug

Vaporized CBD (40 mg)

Other names: Cannabis

CBD 80 mg

Drug

Vaporized CBD (80 mg)

Other names: Cannabis

Primary outcomes

  1. Subject-rated drug effects of abuse liability

    Time frame: 3 hours

    Subject ratings of "Good Drug Effect" as measured using a visual analog scale (1-100 mm)

  2. Analgesia as measured using the Cold Pressor Test

    Time frame: 3 hours

    Pain threshold assessed using the Cold Pressor Test (percent baseline)

  3. Behavioral task performance as assessed by the DRUID App Score

    Time frame: 3 hours

    Trough composite scores on the DRUID App

  4. Pharmacokinetics of THC

    Time frame: 3 hours

    Peak plasma levels of THC (ng/ml)

Study contacts

Contact information is provided by the study sponsor or research team.

Vincent Acebo

CONTACT

[email protected]

310-983-3417

Ziva Cooper, PhD

CONTACT

[email protected]

310-206-9942

Sponsors and collaborators

Lead sponsor

University of California, Los Angeles

Other

Registry information

Official study title

Interactions Between Delta-9-THC and CBD: A Controlled Human Drug-administration Study Probing a Harm Reduction Strategy

Acronym: THC-REDUX

Important dates

Study start
2025
Primary completion
2027
Study completion
2028
First posted
Mar 5, 2025
Registry last updated
Dec 17, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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