Studies of Cannabinoid-Based Products in ClinicalTrials.gov: A Scoping Review

Background and Objectives: There is increased interest in using cannabinoid-based products for therapeutic purposes. Because of unique regulatory challenges associated with these products, understanding the state of current research is critical to inform future research. The objective of this review was to survey the characteristics of registered studies on ClinicalTrials.gov that describe using cannabinoid-based products as an intervention. Methods: The scoping review was conducted in accordance with the PRISMA-ScR checklist and guidance. Eligible studies registered on ClinicalTrials.gov that used cannabinoid-based products as an intervention included those using approved drugs, compounds (nonapproved drugs/extracts with defined phytocannabinoid content), cannabis (whole cannabis products), and hemp (hemp-derived products and products without defined cannabinoid content). Data were extracted on October 1, 2023. Statistical analyses were descriptive. Results: Of 2428 identified records, 879 interventions from 825 unique studies were eligible for analysis. Studies included drugs (n = 287 [32.7%]), compounds (n = 383 [43.6%]), cannabis (n = 178 [20.3%]), and hemp (n = 31 [3.5%]). The most common MeSH categories were psychological disorders (n = 170 [20.6%]), pathological conditions-signs and symptoms (n = 153 [18.5%]), nervous system diseases (n = 127 [15.4%]), substance use disorders (n = 97 [11.7%]), and healthy volunteers (n = 77 [9.3%]). Of the 825 unique studies, 521 (63.2%) were early phase 1 to phase 2/3, 103 (12.5%) phase 3, and 40 (4.8%) phase 4; 161 (19.5%) were not assigned a phase. Sponsors were academic institutions/hospitals (70.5%), pharmaceutical/commercial entities (26.8%), government (2.5%), and an individual (0.1%). Most studies (54.2%) had fewer than 50 participants. Mean and median enrollment were 104 and 41. Mean and median duration were 837 and 717 days. Submitted studies increased over time. Conclusion: Registered studies using cannabinoid-based interventions were typically phase 2, randomized, and small (<50 participants). The results highlight the diverse nature of clinical studies across disease states and reinforce the need for larger, placebo-controlled studies.