A Double-blind, Placebo-controlled Study to Evaluate Very Low Dose LSD in Healthy Volunteers Aged 55-75 Years

This study was a Phase 1, double-blind, placebo-controlled, randomised study of very low dose LSD. Healthy volunteers aged 55 to 75 years with no use of LSD in the past 5 years were screened within 28 days of randomization. Subjects who met all inclusion and no exclusion criteria and provided written informed consent were randomised a 1:1:1:1 ratio to receive 6 doses of 5 µg, 10 µg, or 20 µg LSD or placebo, at 4-day intervals for 21 days (on Study Days 1, 5, 9, 13, 17, and 21). A follow-up visit was conducted approximately 4 weeks after the last dose of LSD. A total of 48 subjects were enrolled.