# Cannabidiol and Cannabis Concentrate Users: A Randomized, Placebo Controlled Study

> **NIH NIH P50** · UNIVERSITY OF COLORADO DENVER · 2024 · $353,967

## Abstract

PROJECT SUMMARY/ABSTRACT
 PROJECT 2: ADULT STUDY
As cannabis legalization continues to spread across the United States, average Δ9-tetrahydrocannabinol (THC)
concentrations in recreational products have significantly increased, with levels as high as 90-95% in
concentrated preparations. Our preliminary data suggest that concentrate use elicits blood THC levels more than
twice as high as cannabis flower use, and that concentrate use is associated with greater tolerance and loss of
control over cannabis use, prompting concern about the risks of these products. Several previous studies have
found that the non-intoxicating cannabinoid cannabidiol (CBD), which may antagonize the effects of THC on CB1
and CB2 receptors, reduces cannabis use, subjective response to THC, and craving. Pilot data from our lab also
suggest that CBD reduces THC effects, drug reward, anxiety, and overall THC use, suggesting that CBD may
mitigate the harms of high-THC products. However, the therapeutic dose of CBD necessary to achieve these
effects is unknown.
The overarching aim of this proposal is to combine our naturalistic cannabis administration paradigm
with a placebo-controlled, dose-ranging RCT of plant-derived CBD to evaluate CBD effects on cannabis
concentrate use, subjective effects, and cannabis cue reactivity. We will recruit 120 frequent concentrate
users to complete a four-week protocol during which they will complete two sessions in our mobile pharmacology
lab. In each session, participants will use their typical cannabis concentrate on an ad libitum basis. Amount of
THC self-administration during these sessions will be quantified by THC blood levels, obtained in the mobile lab
immediately before and after use. Subjective drug effects and exogenous and endogenous cannabinoid
biomarkers will also be quantified before and after THC use. Immediately after the first mobile lab session,
participants will be randomly assigned to take either 200 mg or 400 mg of plant-derived, broad spectrum CBD
or matched placebo (40 participants per group) daily for four weeks. Participants will return after two weeks to
provide a blood sample that will be analyzed for the THC metabolite 11-nor-9-carboxy-Δ9-THC (THC-COOH) to
detect recent cannabis use and for CBD levels to detect medication adherence. At this session, participants will
also complete a cannabis cue reactivity paradigm. Participants will complete a second mobile lab session after
four weeks of study medication ingestion.

## Key facts

- **NIH application ID:** 10912687
- **Project number:** 5P50DA056408-02
- **Recipient organization:** UNIVERSITY OF COLORADO DENVER
- **Principal Investigator:** JOSEPH P. SCHACHT
- **Activity code:** P50 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2024
- **Award amount:** $353,967
- **Award type:** 5
- **Project period:** 2023-09-01 → 2028-06-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10912687

## Citation

> US National Institutes of Health, RePORTER application 10912687, Cannabidiol and Cannabis Concentrate Users: A Randomized, Placebo Controlled Study (5P50DA056408-02). Retrieved via AI Analytics 2026-05-25 from https://api.ai-analytics.org/grant/nih/10912687. Licensed CC0.

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