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

Phase 1

Not yet recruiting

• Conditions: Abuse, Drug; Pain
• Interventions: Drug: Placebo; Drug: THC; Drug: CBD 20 mg; Drug: CBD 40 mg; Drug: CBD 80 mg

• Registration Number: NCT06859710
• Lead Sponsor: University of California, Los Angeles

Brief Summary

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

Detailed Description

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.

Study Timeline

• Study First Submitted: 2025-02-25
• Status Verified: 2025-03
• Study First Submitted QC: 2025-03-03
• Last Update Submitted: 2025-03-03
• Study First Posted: 2025-03-05
• Last Update Posted: 2025-03-05
• Study Start: 2025-06-01
• Primary Completion: 2027-06-01
• Study Completion: 2028-06-01

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: All
• Target Recruitment: 30

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

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Placebo	Placebo	0 mg THC, 0 mg CBD
THC	THC	20 mg THC, 0 mg CBD
CBD 20	CBD 20 mg	0 mg THC, 20 mg CBD
CBD 40	CBD 40 mg	0 mg THC, 40 mg CBD
CBD 80	CBD 80 mg	0 mg THC, 80 mg CBD
THC with CBD 20	THC	20 mg THC, 20 mg CBD
THC with CBD 20	CBD 20 mg	20 mg THC, 20 mg CBD
THC with CBD 40	THC	20 mg THC, 40 mg CBD
THC with CBD 40	CBD 40 mg	20 mg THC, 40 mg CBD
THC with CBD 80	THC	20 mg THC, 80 mg CBD
THC with CBD 80	CBD 80 mg	20 mg THC, 80 mg CBD

Primary Outcome Measures

Name	Time	Method
Subject-rated drug effects of abuse liability	3 hours	Subject ratings of "Good Drug Effect" as measured using a visual analog scale (1-100 mm)
Analgesia as measured using the Cold Pressor Test	3 hours	Pain threshold assessed using the Cold Pressor Test (percent baseline)
Behavioral task performance as assessed by the DRUID App Score	3 hours	Trough composite scores on the DRUID App
Pharmacokinetics of THC	3 hours	Peak plasma levels of THC (ng/ml)