A Randomized, Double-Blind, Dose Response Phase 2 Pilot Study of Manualized MDMA-Assisted Psychotherapy in Subjects With Chronic, Treatment-Resistant Posttraumatic Stress Disorder (PTSD)

This Phase 2 pilot study is a randomized, double-blind, dose response study to examine the safety and efficacy of MDMA-assisted psychotherapy in 23 subjects with chronic, treatment-resistant PTSD of at least six months duration. This study assessed two active doses of MDMA, active dose 1 (100 mg) and active dose 2 (125 mg), to a comparator dose of MDMA (40 mg) during psychotherapy sessions. The initial dose of MDMA was followed 1.5 to 2.5 hours later by an optional supplemental dose of MDMA that was half the size of the first dose. MDMA was administered orally in two experimental sessions lasting up to eight hours and scheduled three to five weeks apart. Subjects were prepared for MDMA-assisted psychotherapy in three preparatory sessions prior to the first experimental session, and worked with the same pair of therapists throughout the study. After each experimental session, three integrative sessions were scheduled with the subject, including one integrative session the morning after the experimental session. During integrative sessions, subjects processed and connected their thoughts and feelings about the experience with their therapist team. Subjects who received the comparator dose (40 mg) were given the option to enroll in Stage 2, where they underwent three open-label MDMA-assisted psychotherapy sessions. 100 mg of MDMA was administered in the first session and therapists determined whether to increase to 125 mg of MDMA for the second and third experimental sessions. People who received 125 mg of MDMA during the first two experimental sessions received the same dose during an open-label third experimental session. People who received 100 mg of MDMA during the first two sessions were able to choose, in consultation with their therapist, to either continue to receive 100 mg in a third session or to increase their dose to 125 mg. A blinded independent rater (IR) assessed the severity of PTSD symptoms at baseline, one month after the second experimental session (the primary endpoint), two months after the third open-label experimental session, and at equivalent points in Stage 2.