Overview
This study will examine the effects of a single dose of psilocybin, administered with psychological support, on symptoms of depression. It will also assess whether different post-dosing interventions, including a non-invasive technique called transcutaneous auricular Vagus Nerve Stimulation (taVNS), influence various psychological and behavioral outcomes. In addition, the study will explore objective measures of real-world social behavior and identify early behavioral responses that may be associated with long-term treatment outcomes.
Description
One hundred forty-one adults ages 18 to 70 experiencing a major depressive episode of at least 60 days duration of moderate or greater severity at screening will be enrolled to obtain evaluable data on approximately 120 subjects.
All subjects will receive a single 25 mg dose of psilocybin using a "set and setting" therapeutic approach that will include 1) several hours of preparatory sessions prior to dosing and 2) the presence of two facilitators throughout the dosing session; and 3) several post dosing integration sessions with a facilitator.
Following the psilocybin dosing session, subjects will be randomized to 1) taVNS (7 days of twice daily taVNS), 2) sham taVNS (7 days of twice daily sham taVNS), or 3) no taVNS.
Both taVNS and sham sessions will include guided prompts encouraging participants to reflect on key aspects of their psychedelic experience, accompanied by music previously used during the psilocybin dosing session.
Participants will complete assessments at multiple time points to evaluate depression, anxiety, well-being, functional disability, quality of life, social behavior, suicidal ideation, and adverse events before and after psilocybin dosing.
Eligibility
Inclusion Criteria:
Current diagnosis of Major Depressive Disorder (MDD), with a depressive episode lasting ≥ 60 consecutive days at the time of screening, as confirmed by structured clinical interview
Medically healthy, as determined by the screening physician, with no significant medical conditions that would interfere with participation or affect the safety of the subject.
Exclusion Criteria:
History or presence of any psychiatric or medical condition that, in the opinion of the investigator, could pose a safety risk, interfere with participation, or confound study results (e.g., bipolar disorder, psychosis, seizure disorder, or cardiovascular disease).
Known family history of a psychotic disorder (e.g., schizophrenia or schizoaffective disorder) in a first-degree relative (biological parent, full sibling, or child).
Current active suicidal ideation with a specific plan within the prior 2 weeks, as assessed via clinical interview and validated instrument (e.g., C-SSRS).
Suicide attempt within the prior 6 months, regardless of intent or lethality.
Current diagnosis of a substance use disorder
Abnormal ECG at screening that may increase risk during participation (e.g., prolonged QTc, arrhythmias, or other clinically significant findings as determined by the study physician).
Unwilling or unable to discontinue prescription psychotropic medications (e.g., antidepressants, antipsychotics, anxiolytics, lithium, anticonvulsants, or mood stabilizers) for the duration of study participation, including any necessary washout period as determined by the investigator.
Any condition, finding, or behavior (including suspected deception or noncompliance) that, in the opinion of the investigator, renders the participant unsuitable for the study or likely to interfere with the integrity of the data or safety of the subject.