Psilocybin-assisted CBT for Depression

The primary objectives of this clinical investigation are to (1) determine the acceptability and feasibility of joining psilocybin-assisted therapy with cognitive-behavioral therapy (PA-CBT) for patients with depression, (2) optimize CBT to most effectively integrate the psilocybin experience with psychotherapy and (3) examine the clinical benefit of psilocybin as an adjunct to cognitive-behavioral therapy (CBT) for major depressive disorder. This study has two phases. Phase I will involve an open trial of PA-CBT where participants will receive two doses of psilocybin (10mg and then 25mg, separated by one month) plus 12 sessions of cognitive behavioral therapy. Phase II will be a randomized, two-arm, fixed dose trial that will test the feasibility, acceptability, and participant and therapist adherence to PA-CBT. Both treatment arms will receive two doses of psilocybin (10mg and then 25mg, separated by one month). In Phase II, participants will be randomized (1:1) to either a 12-session PA-CBT or a 6-session standard psilocybin-assisted therapy (PAT) condition (3 hours of preparation plus 3 hours of supportive therapy integration following the psilocybin experiences).