The goal of this clinical trial is to investigate treatment with psilocybin and psychotherapy for the treatment of people with Alcohol Use Disorder (AUD). The main question[s] it aims to answer are:

• Does treatment with psilocybin and therapy help reduce alcohol consumption more than placebo and therapy?
• Is treatment with psilocybin and therapy safe for participants?

Participants will

• Attend 13 study visits
• Take part in therapy sessions including 2 treatment sessions with either psilocybin or placebo
• Record their daily alcohol consumption on study specific device

Researchers will compare psilocybin and placebo groups to see if alcohol consumption is decreased.

Inclusion Criteria:

• Moderate to severe diagnosis of AUD as measured by Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) criteria using Structured Clinical Interview for DSM-5 by the investigator.
• Expressed a wish to reduce or stop alcohol consumption.
• Generally healthy with no unstable medical conditions, as determined by medical history, physical examination, routine blood labs, electrocardiogram, urine analysis, and urine toxicology.

Exclusion Criteria:

• Diagnosed with or having a family history of any of the following concomitant psychiatric disorders: schizophrenia or prodromal symptoms, any bipolar disorder, obsessive compulsive disorder, or other psychotic episode. Recent (within last 12 months) diagnosis of a major depressive disorder (MDD) (HAM-D score >19), treatment resistant depression (TRD), post-traumatic stress disorder (PTSD), panic disorder, or eating disorders.
• Subjects deemed unfit for psilocybin-assisted therapy based on the assessments made during psychotherapy sessions prior to the first psilocybin-assisted psychotherapy session.
• History of hallucinogen use disorder, or any use in the past 1 year, or >25 lifetime uses.