Journal of Humanistic Psychology, Ahead of Print.
Background: Posttraumatic stress disorder (PTSD) is a debilitating mental health condition associated with serious adverse health outcomes and functional impairment. Previous MDMA–assisted therapy (MDMA-AT) studies have shown promising results in single site studies. Two open-label studies tested this modality in multisite clinical trials to assess the feasibility of scaling this manualized therapy across 14 North American sites. Method: Cotherapist dyads were trained in the manualized MDMA-AT protocol and administered three experimental sessions 3 to 5 weeks apart among participants with severe PTSD. Cotherapist dyads were provided clinical supervision and evaluated for protocol adherence by centralized raters. Clinician-Administered PTSD Scale for DSM-5 (CAPS-5) assessed change in symptoms severity. Results: Adherence rating scores were high across cotherapist dyads (M = 95.08%, SD = 3.70%) and sites (M = 95.23%, SD = 2.20%). CAPS-5 scores decreased following 3 MDMA-AT sessions at 18 weeks post baseline (ΔM = −29.99, ΔSD = 13.45, p < .0001, n = 37, Cohen’s d = 2.2, confidence interval [1.97, 2.47]). MDMA was well tolerated. Conclusions: These findings corroborate previous results that MDMA-AT can achieve significant improvements in PTSD symptom severity and demonstrate scalability of manualized therapy across clinic sites in the United States and Canada.