A Phase 1 trial tests psilocybin for borderline personality disorder while keeping dialectical behavior therapy in place

A University of Minnesota Phase 1 trial will study two 25 mg doses of psilocybin in 18 adults with borderline personality disorder who are already established in dialectical behavior therapy and will continue weekly individual therapy, group skills training, and phone coaching throughout the 18-week study. The open-label, single-group ADEPT trial prioritizes safety and feasibility rather than efficacy, measuring acute suicidal ideation, challenging experiences, side effects, retention, and DBT attendance. Participants with active suicidal intent or a recent suicide attempt are excluded, so results will apply only to a carefully screened subgroup. The design addresses a longstanding concern that psychedelic trials may destabilize people with emotion dysregulation and elevated suicide risk. Earlier evidence consisted of one nine-person open-label study in people with depression and co-occurring borderline personality disorder, which found improved depression but no significant change in borderline symptoms. The trial is not yet recruiting and is estimated to run from December 2026 to December 2030.