NCT04998006 (FRACTAL) is a clinical trial in Cannabis Use, sponsored by University of Colorado, Denver.

Who is sponsoring NCT04998006?

NCT04998006 is sponsored by University of Colorado, Denver.

What condition does NCT04998006 study?

NCT04998006 studies Cannabis Use, Alcohol Use, Inflammation.

Is NCT04998006 still recruiting?

NCT04998006 is currently completed. Last updated 10 November 2025.

Last reviewed 2025-11-10 · How we verify

NCT04998006: FRACTAL

Name: Drug Landscape Pharmaceutical Database
Creator: Drug Landscape
Published: 2026-01-01
License: https://creativecommons.org/licenses/by/4.0/

Alcohol and Cannabis Co-Use and the Gut-Brain Axis

Completed Last updated 10 November 2025

What this trial tests

trial in Cannabis Use in 77 participants. Completed in 23 December 2024.

Timeline

25 February 2022

Primary endpoint
23 December 2024

23 December 2024

Quick facts

Lead sponsor	University of Colorado, Denver
Status	Completed
Study type	OBSERVATIONAL
Enrollment	77
Start date	25 February 2022
Primary completion	23 December 2024
Estimated completion	23 December 2024
Sites	1 location across United States

Conditions studied

Cannabis Use — all drugs for Cannabis Use →
Alcohol Use — all drugs for Alcohol Use →
Inflammation — all drugs for Inflammation →

Sponsor

University of Colorado, Denver

Who can join

Adults 21 to 60, any sex, with Cannabis Use or Alcohol Use. Patients with the condition only — healthy volunteers not accepted.

Sponsor's own description

This observational study aims to improve our understanding of how legal market cannabis use impacts acute and long-term alcohol use, the microbiota-gut-brain-axis (MGBA), and neurobehavioral alcohol use phenotypes such as impulsivity, impaired cognitive functioning, and craving, among individuals who regularly use both alcohol and cannabis. Over a period of one month, subjects will participate in this three-visit study. Blood samples will be collected to allow for the assessment of inflammatory markers and cannabinoids, a fecal sample will be collected to allow for the analysis of the gut microbiome, and participants will complete cognitive and impulsivity tasks and provide craving ratings during the course of an alcohol self-administration procedure. Subjects will also participate in two 14-day daily diary data collection periods between lab sessions. Daily diary data collection will be used to assess the effects of cannabis use on alcohol use and craving longitudinally.

Publications & conference data

4 peer-reviewed publications reference this trial (live from Europe PMC):

Cannabis administration is associated with reduced alcohol consumption: Evidence from a novel laboratory co-administration paradigm.
Pince CL, Stallsmith VT, Piercey CJ, Weldon K, et al · · 2025 · cited 1× · PMID 40915022 · DOI 10.1016/j.drugalcdep.2025.112860
Behavioral phenotypes associated with cannabis and alcohol substitution.
Pince CL, Piercey CJ, Stallsmith VT, Weldon K, et al · · 2026 · PMID 41792806 · DOI 10.1186/s12954-026-01432-y
Behavioral Phenotypes Associated with Cannabis and Alcohol Substitution
Pince C, Piercey CJ, Stallsmith VT, Weldon K, et al · · 2025 · DOI 10.31234/osf.io/z5vwk_v3
Effects of legal-market cannabis and alcohol on verbal learning and memory.
Gowin JL, Stallsmith V, Weldon K, Dooley G, et al · · 2026 · PMID 40996525 · DOI 10.1007/s00213-025-06882-z

Verify or expand the search:

Other recruiting trials for Cannabis Use

Currently open trials in the same condition.

NCT07196462 — Precision Brain Stimulation to Reduce Cannabis Craving in Schizophrenia · NA · recruiting
NCT07168707 — Culturally Adapted EAET-H for Chronic Pain Patients Using Medical Cannabis in Israel - A Pilot Study · NA · recruiting
NCT05999383 — Understanding the Clinical Pharmacology of Marijuana-Tobacco Co-administration · Phase 2 · recruiting
NCT06883162 — Cannabis-Tobacco Co-Use Treatment Study · Phase 3 · recruiting
NCT06699251 — Effectiveness of Brief Intervention in Primary Care for Diverse Young People (Chat) · NA · recruiting

Other University of Colorado, Denver trials

Trials by the same sponsor.

NCT07292285 — The Surveillance Nonoperative Watch & Wait (SNOWW) Rectal Cancer Trial. · not yet recruiting
NCT07021937 — Brain Plasticity and GLP-1 Receptor Agonist Treatment for Obesity · Phase 3 · not yet recruiting
NCT07453732 — Banana Leaves as a Wound Dressing for Partial Thickness Second Degree Burns in Adult Patients. · NA · not yet recruiting
NCT07038278 — 5-AminoLevulinic Acid Aided Resection Margins in Sarcoma · EARLY_PHASE1 · not yet recruiting
NCT07279558 — Cannabidiol and Alcohol Use Disorder Phenotypes · Phase 2 · recruiting

Verify against primary sources

ClinicalTrials.gov — authoritative US registry record
WHO ICTRP — international registry index
EU Clinical Trials Register
Sponsor press releases (Google)

Data sources for this page

Trial protocol + status: ClinicalTrials.gov NCT04998006 (US National Library of Medicine, public domain)
Publications: Europe PMC API search by NCT ID, retrieved 10 June 2026
Drug + disease cross-links: matched in real time against Drug Landscape's normalised drug + company + condition tables
Sponsor: as reported to ClinicalTrials.gov by University of Colorado, Denver
Last refreshed: 10 November 2025

Drug Landscape aggregates and links these public records for informational use only. Always verify against the primary source before clinical or regulatory decisions. Canonical URL: https://druglandscape.com/trial/NCT04998006.

Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing