January 15, 2026
Benjamin Kelmendi, Thomas G. Adams, Terence H. W. Ching et al.
preprint
Background: Obsessive-compulsive disorder (OCD) affects 2-3% of the population worldwide. 40-60% of patients do not respond to first-line interventions. We evaluated the efficacy and safety of a single dose of psilocybin in patients with treatment-resistant OCD.Methods: In this phase 2, randomized, double-blind trial, we randomly assigned 28 adults with treatment-resistant OCD to receive a...
SSRN Electronic Journal
2026
Ben Kelemndi, Thomas G. Adams, Terence H. W. Ching et al.
1 citation
Background: Obsessive-compulsive disorder (OCD) affects 2–3% of the population worldwide, and 40–60% of patients do not respond to first-line treatments. We evaluated the efficacy and safety of a single dose of psilocybin in adults with treatment-resistant OCD.Methods: In this phase 2, randomised, double-blind, placebo-controlled trial at the Connecticut Mental Health Center, Yale University...
Frontiers in Psychiatry
December 10, 2025
Terence H. W. Ching, B. Stahnke, Sarah Shnayder et al.
3 citations
Introduction The subjective effects of psilocybin on obsessive-compulsive disorder (OCD) are under-explored. Therefore, we conducted a qualitative study of participant experiences from the first randomized placebo-controlled trial of single-dose psilocybin combined with unstructured and non-directive support for individuals with treatment-refractory OCD. Our research explored how participants...
Frontiers in Psychiatry
April 25, 2023
Rachael Grazioplene, Calvin Bohner, Giuliana DePalmer et al.
27 citations
Background Psilocybin may help treat obsessive–compulsive disorder (OCD). To date, only one open-label study of psilocybin for OCD exists, necessitating further investigation with a randomized controlled design. The neural correlates of psilocybin’s effects on OCD have also not been studied. Objectives This first-of-its-kind trial aims to evaluate the feasibility, safety, and tolerability of...
Heliyon
December 1, 2022
Benjamin Kelmendi, Giuliana DePalmer, Gayle Maloney et al.
34 citations
Classic psychedelics, such as psilocybin, act on the brain's serotonin system and produce striking psychological effects. Early work in the 1950s and 1960s and more recent controlled studies suggest benefit from psychedelic treatment in a number of conditions. A few case reports in recreational users and a single experimental study suggest benefit in patients with obsessive-compulsive disorder...
October 5, 2022
Terence H. W. Ching, Stephen A. Kichuk, Giuliana DePalmer et al.
5 citations
preprint
The Yale Program for Psychedelic Science (YPPS) is testing the safety and efficacy of psilocybin, administered in conjunction with non-directive psychological support, as a treatment for certain neurological and psychiatric conditions. The study, HIC: 200020355 (Neural correlates of the effects of psilocybin in obsessive-compulsive disorder: A double-blind, placebo-controlled study), will...