The primary objectives of this clinical investigation are to (1) determine the acceptability and feasibility of joining psilocybin-assisted therapy with cognitive-behavioral therapy (PA-CBT) for patients with depression, (2) optimize CBT to most effectively integrate the psilocybin experience with psychotherapy and (3) examine the clinical benefit of psilocybin as an adjunct to cognitive-behavioral therapy (CBT) for major depressive disorder.

This study is a randomized, two-arm, fixed dose trial that will test the feasibility, acceptability, and participant and therapist adherence to PA-CBT. Both treatment arms will receive two doses of psilocybin (10mg and then 25mg, separated by one month). In Phase II, participants will be randomized (1:1) to either a 12-session PA-CBT or a 6-session standard psilocybin-assisted therapy (PAT) condition (3 hours of preparation plus 3 hours of supportive therapy integration following the psilocybin experiences).

Inclusion Criteria:

• Ages 21-60,

  • Able to swallow capsules,
  • Patients with a current major depressive episode or a history of major depressive episodes based on the DSM-5 criteria (American Psychiatric Association, 2013),
  • Active current depressive symptoms (i.e., scores >16 on the Hamilton-Depression Rating Scale (HAM-D) covering the prior 2 weeks; Hamilton, 1986),
  • Have an identified support person who can pick up the individual from UCLA Semel Institute and drive individual home following psilocybin sessions,
  • For women of child-bearing potential - using one form of highly effective contraception (e.g., oral contraceptive pill) and willingness to continue contraceptive use for duration of study
  • Patient has been medically cleared for the study by a physician.

Exclusion Criteria:

• A personal or family history (first or second-degree) of psychosis or bipolar disorder

  • Resting blood pressure above 140 systolic, 90 diastolic (averaged across four separate measurements)
  • Meeting criteria for a DSM-5 cluster B personality disorder (narcissistic, histrionic, borderline, antisocial personality disorder),
  • Active suicidality (as indicated by a 3 or greater on item 3 of the HAM-D) or other psychiatric disturbance requiring acute treatment
  • Current use of antidepressants or other serotonergic-affecting substances (e.g., St. John's Wort and 5-hydroxytryptophan),
  • Currently receiving cognitive behavioral therapy,
  • Any of the following cardiovascular conditions: uncontrolled hypertension, coronary artery disease, congenital long QT syndrome, cardiac hypertrophy, cardiac ischemia, congestive heart failure, myocardial infarction, tachycardia, artificial heart valve, a clinically significant screening ECG abnormality, or any other significant cardiovascular condition
  • A history of stroke or Transient Ischemic Attack (TIA)
  • Epilepsy or history of seizures
  • Insulin-dependent diabetes
  • Meeting criteria for a DSM-5 substance abuse or dependence within prior 6 months
  • Positive urine drug screen for illicit substances
  • Use of other psychedelics or ketamine within prior 12 months
  • Adverse prior reaction to a psychedelic agent
  • Pregnant, trying to get pregnant, or nursing