This interventional randomised, blinded, parallel Phase II trial (n=40) compares MDMA-assisted psychotherapy (3 × 100 mg oral sessions) to psilocybin-assisted psychotherapy (3 × 25 mg oral sessions) for treatment-resistant OCD, with preparatory and integration therapy.
Randomised, blinded, parallel Phase II study enrolling 40 participants with treatment‑resistant obsessive‑compulsive disorder to compare MDMA‑assisted psychotherapy and psilocybin‑assisted psychotherapy, each delivered as three single‑dose medication sessions with structured psychological support.
Each medication arm includes a minimum of two 90‑minute preparation sessions, three medication sessions (up to 8 hours each, 2–6 weeks apart) and four 90‑minute integration sessions; therapists are trained health professionals and adherence is recorded electronically.
A subset of participants will undergo EEG at baseline and after the first and third drug sessions where equipment is available. Primary outcome includes change in Yale‑Brown Obsessive Compulsive Scale (YBOCS) scores; other measures include depression scales and follow‑up at 1, 3 and 6 months post‑integration.
Three single-dose MDMA-assisted psychotherapy sessions (2–6 weeks apart) with preparatory and integration therapy.
Single 100 mg oral capsule administered by medical practitioner; sessions 2–6 weeks apart.
Three single-dose psilocybin-assisted psychotherapy sessions (2–6 weeks apart) adapted from Yale manual, with preparatory and integration therapy.
Single 25 mg oral capsule administered by medical practitioner; sessions 2–6 weeks apart.