Study of Psilocybin for Anorexia in Young Adults

Inclusion Criteria:

• Able to understand and provide informed consent.

• Between 18 and 25 years old at time of screening.

• Meets Diagnostic and Statistical Manual (DSM-5) criteria for any type of AnorexiaNervosa

• Currently experiencing symptoms of Anorexia Nervosa

• Persistence of Anorexia Nervosa diagnosis after at least one attempt of eatingdisorder focused treatment or higher level of care

• Comfortable reading and writing in English

• Have no anticipated changes in medication or surgical procedures for trial duration

• Commit to attend all in-person and remote study visits and participate in all datacollection procedures

• Able to identify two family members or close friends to co-enroll in the study, whowill be required to participate in select therapy sessions, pick them up and staywith them overnight on dosing days.

• Agree to use a highly effective form of contraception for two weeks prior tostarting the study and one month after finishing the study.

• Agree that for one week preceding each psilocybin session, they will refrain fromtaking any nonprescription medication, nutritional supplement, or herbal supplementexcept when approved by the research team. Exceptions will be evaluated by theresearch team and will include acetaminophen, non-steroidal anti-inflammatory drugs,and common doses of vitamins and minerals.

• Agree to consume approximately the same amount of caffeine-containing beverages (e.g., coffee, tea) that they usually consume before arriving at the research uniton the mornings of psilocybin administration sessions. If the young adultparticipant does not routinely consume caffeinated beverages, they must agree not todo so prior to psilocybin administration sessions.

Exclusion Criteria:

• Current known pregnancy or positive pregnancy test at any time during the study

• Personal history of bipolar disorder, or psychotic disorder verified by theStructured Clinical Interview for DSM-5 (SCID) and medical history at screening

• Body Mass Index less than 12 at screening

• Unstable vital signs including Blood Pressure, Heart Rate, or Temperature

• Abnormal Safety Labs including sodium, potassium, magnesium, phosphorus, creatinine,estimated Glomerular Filtration Rate, Aspartate Transferase, Alanine Transaminase

• Electrocardiogram abnormalities

• Hospitalization or participation in a residential program for more than 2 of thepast 4 weeks at the time of screening.

• Unwilling to abstain from alcohol, Cannabidiol (CBD), tetrahydrocannabinol (THC),marijuana, and illicit drug use for 48 hours pre and post psilocybin dosing days andabstain from nicotine for 10 hours pre and post psilocybin dosing.

• Positive urine toxicology testing for amphetamines, benzodiazepines, cocaine,cannabis, 3,4-Methylenedioxymethamphetamine (MDMA), and opioids (including methadoneand buprenorphine) on the morning of either psilocybin administration session.

• History of cardiovascular disease

• Uncontrolled endocrine conditions, including diabetes, hyper or hypothyroidism

• Significant and uncontrolled gastrointestinal illness at the discretion of theinvestigator

• Significant and uncontrolled neurological disease including uncontrolled seizuredisorder at the discretion of the investigator

• Use of any prohibited concomitant medications or inability or unwillingness todiscontinue according to the study's prescribed medication taper or tapering withthe participants primary prescriber.

• Inability or unwillingness to stop outside psychotherapy from time of firstpreparation session to B28 visit

• Needle phobia.

• Simultaneous enrollment in another clinical trial.

• Pregnant or Breast feeding.

• Allergy or intolerance to any of the materials contained in the drug product

• History of severe reaction to psychedelics at the discretion of the investigators.

• High risk of self-harm/suicide

• Mental health condition that will prevent engagement with the treatment team.

• Unwilling or unable to participate in the treatment protocol as planned, includinghydration with sports drinks on dosing days.

• If any study physician feels that it would be unsafe to continue for any mental,physical or other reason