The trial is the first to identify a safe, active, non-psychedelic dosage of psilocybin. TORONTO, Dec. 7, 2022 /PRNewswire/ – Diamond Therapeutics Inc. (“Diamond”), a drug development company focused on low-dose psychedelic-derived therapies for use in the treatment of mental health, announces the successful completion of its Phase I clinical study of low-dose psilocybin.