Efficacy in Relapse Prevention: Psilocybin in Alcohol Use Disorder With Depressive Symptoms

Inclusion Criteria: * Confirmed DSM-5 diagnosis of severe AUD. * Scale BDI-II ((Beck Depression Inventory) ≥14 * The last drink must have been consumed between day(D) -60 and D -10 at the inclusion visit. The patient must have had at least 1 HDD during the last drinking period NB: The last drinking period before inclusion is defined by the last 4 weeks counted from the last drink. * The patient must have given their free and informed consent and signed the consent form * The patient must be a member or beneficiary of a health insurance plan Exclusion Criteria: * The subject is participating in an interventional study, a clinical trial, or a clinical investigation or is in a period of exclusion determined by a previous study * The subject refuses to sign the consent * It is impossible to give the subject informed information * The patient is under safeguard of justice or state guardianship * Patient unable to give informed consent. * Participants planning to donate sperm within three months of psilocybin administration * Positive pregnancy test at inclusion for participants of childbearing age. * Patient who is pregnant, breastfeeding, or wishing to become pregnant during participation in the study. * Any use of classical psychedelic in the last year * Other current substance use disorder (except tobacco) * Diagnosed schizophrenic or bipolar disorder * High emotional lability (clinician-judged) * On antipsychotics treatment that may interfere with psilocybin. * Need for monoamine oxidase inhibitor (MAOI) treatment, which may interfere with psilocybin. * Severe suicidal ideation (high risk on the Columbia scale) * 1st degree family member with a diagnosed psychotic disorder * Severe cognitive impairment (clinician-judged) * CIWA-AR \> 8 * Medical conditions that would preclude safe participation in the trial, for example: seizure disorders; significant impairment of hepatic function; coronary artery disease; history of arrhythmia; Abnormal QT interval prolongation (QTc \> 470 ms for women and \>450 ms for men); heart failure; uncontrolled hypertension (greater than 165/95 mmHg at screening); history of stroke; severe asthma; hyperthyroidism; narrow-angle glaucoma; stenosing gastroduodenal ulcer; pyloroduodenal obstruction; symptomatic prostatic hypertrophy or bladder neck obstruction; uncontrolled type I or type II diabetes, or a history of ketoacidosis, hyperglycemic coma, or severe hypoglycemia with loss of consciousness.