Trial oversight
treatment-resistant MDD
This was a phase II, exploratory, fixed-dose, open-label study conducted between August 2020 and September 2021. This trial explored the safety and efficacy of a single dose of 25 mg of the investigational drug COMP360, a proprietary pharmaceutical-grade synthetic psilocybin formulation, optimized for stability and purity, adjunct to an antidepressant drug in participants experiencing a current episode of treatment-resistant MDD (EudraCT number: 2018 002377; Clinicaltrials.gov identifier: NCT04739865). COMP360 was supplied by the sponsor, COMPASS Pathfinder Ltd (a subsidiary of COMPASS Pathways plc), London, UK. The protocol was approved by ethics committees at two sites located in Ireland and the United States (US): the Clinical Research Ethics Committee of the Cork Teaching Hospitals (CREC), and the Advarra Center for IRB Intelligence (CIRBI). Participants provided written informed consent prior to participation.The sponsor supervised the study which was conducted by a contract research organization (Worldwide Clinical Trials, Nottingham, UK, and North Carolina, US). The study was conducted in accordance with the International Conference on Harmonisation Good Clinical Practice guideline, and the ethical principles of the Declaration of Helsinki.