Randomised, double-blind, Phase II dose-response study (n=29) comparing MDMA-assisted psychotherapy at 100 mg and 125 mg versus a 40 mg comparator in adults with chronic, treatment-resistant PTSD; three preparatory sessions, two experimental dosing sessions (up to 8 hours) with optional supplemental half-dose, and integration sessions.
Randomised, triple-masked, parallel-group Phase II dose-response trial testing two active doses of oral MDMA (100 mg, 125 mg) versus a comparator dose (40 mg) given across two experimental therapy sessions in adults with chronic PTSD.
Participants received three preparatory psychotherapy sessions, two dosing sessions 3–5 weeks apart (each up to eight hours with an optional supplemental half-dose 1.5–2.5 hours after the initial dose), and three integrative sessions after each experimental session; primary endpoint assessed one month after the second experimental session.
Outcomes included change in PTSD symptom severity (CAPS), safety and tolerability measures; participants who received 40 mg could opt into an open-label stage for additional MDMA-assisted sessions.
Comparator MDMA-assisted therapy (40 mg) across two experimental sessions; optional supplemental half-dose 1.5–2.5 h after initial dose.
Optional supplemental half-dose (20 mg) 1.5–2.5 h after initial dose.
Manualized psychotherapy (3 preparatory sessions, integration sessions after each experimental session).
Active MDMA-assisted therapy (100 mg) across two experimental sessions; optional supplemental half-dose 1.5–2.5 h after initial dose.
Optional supplemental half-dose (50 mg) 1.5–2.5 h after initial dose.
Manualized psychotherapy (3 preparatory sessions, integration sessions after each experimental session).
Active MDMA-assisted therapy (125 mg) across two experimental sessions; optional supplemental half-dose 1.5–2.5 h after initial dose.
Optional supplemental half-dose (62.5 mg) 1.5–2.5 h after initial dose.
Manualized psychotherapy (3 preparatory sessions, integration sessions after each experimental session).
A pooled analysis of six randomised, double‑blind phase 2 trials found MDMA‑assisted psychotherapy produced large, clinically meaningful reductions in PTSD symptoms versus control (MMRM mean difference −22.0; Cohen’s d = 0.8) with higher remission rates (54.2% vs 22.6%) and acceptable tolerability, providing the rationale and design basis for phase 3 trials and FDA Breakthrough Therapy designation.