This non-randomized trial (n=100) investigates the psychological, cognitive, and physiological effects of a single session of psychedelic drug exposure with either psilocybin or MDMA in a group setting.
Open, non-randomised interventional study of single-dose psilocybin or MDMA in healthy, trained participants; allocation by participant preference with sessions delivered individually or in small groups (2–6).
Dosing sessions last ~8 hours with two therapists present; a preparatory session (45–90 minutes) is provided. Primary assessments include psychological, cognitive and physiological measures (e.g., DASS), with secondary electrophysiological outcomes such as EEG N100.
A subset of participants may optionally cross over to receive the alternate substance at least three months later; outcomes are repeated pre- and post-exposure.
Single oral psilocybin session (weight-tiered dosing); sessions may be individual or small groups (2–6).
Weight-tiered single dose: 25 mg (<90 kg), 30 mg (90–115 kg), 35 mg (>115 kg). Administered in capsule form.
Single oral MDMA session with optional booster; sessions may be individual or small groups (2–6).
80 mg initial dose with optional half-dose booster of 40 mg between 1 and 4 hours after initial dose; booster optional.