The Effects of Psilocybin on Self-Focus and Self-Related Processing in Major Depressive Disorder
This open-label functional Magnetic Resonance Imaging (fMRI) study will assess the effects of a single dose of psilocybin on rumination and the neural correlates of rumination in individuals with major depressive disorder.
• Must be able to sign the informed consent form (ICF). Participants will demonstrate capacity to provide informed consent by demonstrated understanding of the protocol and what their involvement in the study requires from them.
• Be 18-55 years of age at screening.
• At least moderate Major Depressive Disorder (MDD; single or recurrent episode as informed by Diagnostic and Statistical Manual Version 5 (DSM-V); if single episode, duration of ≥ 3 months and ≤ 3 years) based on clinical assessment and a structured clinical interview, the Mini International Neuropsychiatric Interview Version 7.02 (MINI).43
• Structured Interview Guide for the Hamilton Depression Rating Scale with Atypical Depression Supplement (SIGH-ADS)44 score ≥ 18 at Screening and at Baseline.
• Failure to respond to an adequate dose and duration of 1, 2, 3, or 4 pharmacological treatments for the current episode as determined through the Massachusetts General Hospital Antidepressant Treatment History Response Questionnaire (MGH-ATRQ)45 and using the supplementary advice on additional antidepressants not included in MGH-ATRQ. Augmentation with an add-on treatment counts as a second treatment, provided it is approved for the adjunctive treatment of MDD.
• McLean Screening Instrument for Borderline Personality Disorder (MSI-BPD) \< 7 at Screening.
• Participants will also have to successfully undergo a taper off of all psychotropic medications under the supervision of a study psychiatrist and in coordination with their treatment team, which will be completed at least 2 weeks prior to Baseline Scan. Please see below regarding details about discontinuation of antidepressants.
• A score \> 40 on the Wechsler Test of Adult Reading.46
• Be right-handed as determined by the Edinburgh Handedness Inventory.48
⁃ Ability to complete all protocol required assessment tools without any assistance or alteration to the copyrighted assessments, and to comply with all study visits.
⁃ Have ongoing established mental health care.