Psilocybin Therapy for Depression in Bipolar II Disorder

The primary goal of this study is to examine the safety, tolerability, and feasibility of psilocybin therapy in people with Bipolar II Disorder (BD II). Fourteen participants, ages 18 to 70 with clinically diagnosed BD II with active depression, in active outpatient mental health treatment, and who meet all other inclusion and exclusion criteria at screening will be enrolled. After baseline assessments, participants will engage in preparatory visits with trained facilitators, followed by an initial drug administration of oral psilocybin,supervised by the facilitators and a clinician who will conduct safety monitoring throughout. Participants will complete assessment and integration sessions with the facilitators subsequently in order to help process the experience. Participants who tolerated the first dosage may be asked to complete a second psilocybin dosing session, involving the same preparation, procedures, integration, and supervision as the first. Primary outcome measures will assess safety, tolerability, and feasibility of study procedures. Efficacy will be measured by change in depression as measured by the MADRS three weeks after the final psilocybin administration. Exploratory outcome measures will assess changes in sleep, quality of life, and therapeutic engagement.