Unequal representation? A cross-sectional analysis of age, sex, race, and ethnicity in clinical trials of classic psychedelics
Journal of Psychopharmacology July 11, 2025 Aleksander Kwaśny, Patrycja Ciurkowska, Wiesław Jerzy Cubała et al. 6 citations
In interventional clinical trials of psilocybin and LSD, participants are overwhelmingly White, raising concerns about whether these therapies are safe and effective for diverse populations. A cross-sectional analysis of nine eligible trials (eight psilocybin, one LSD) registered on ClinicalTrials.gov through January 2025 found that among 501 psilocybin participants, 87.2% were White, 3.0% Black, and 5.0% Asian; ethnicity was reported in only four trials, with 13.4% identifying as Hispanic or Latino. The single LSD trial of 11 older adults reported no race or origin data. Participation-to-population ratios for U.S.-only trials confirmed underrepresentation of Black and Asian individuals. The authors conclude that broader recruitment and standardized reporting are essential to ensure equity and establish safety and efficacy across groups.