Investigation to Understand and Optimize Psilocybin (OPTIMIZE)

This interventional trial (n=141) will investigate the potential enhancement of the antidepressant effects of psilocybin (25mg) through the addition of transcutaneous auricular Vagus Nerve Stimulation (taVNS).

The study, sponsored by Elaine Sandler and conducted at Vail Health Behavioral Health in the United States, will involve participants aged 18 to 70 with major depressive disorder (MDD).

Participants will receive a single 25 mg dose of psilocybin in a controlled therapeutic setting, followed by randomisation into three groups: one receiving taVNS, one receiving sham taVNS, and a control group receiving standard post-dosing integration sessions.

The primary aims are to evaluate the impact of taVNS on the duration and effectiveness of psilocybin’s antidepressant effects and to explore behavioural changes associated with the treatment. Assessments will include measures of depression, well-being, and social behaviour using a range of tools, including the Montgomery-Åsberg Depression Rating Scale (MADRS) and various observational methods.

The study is expected to start in February 2025 and be completed by February 2029.

Topic Depression
Compound Psilocybin
Country United States of America
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