Clinical TrialEating DisordersPsilocybinNot yet recruiting

A clinical trial of psilocybin-assisted psychotherapy as a treatment for anorexia nervosa

Single-group, single-blind Phase I interventional study (n=30) of psilocybin-assisted psychotherapy with three oral dosing sessions (1 mg then 25 mg ×2) given every two weeks in adults with treatment-resistant anorexia nervosa.

Target Enrollment
30 participants
Study Type
Phase I interventional
Design
Non-randomized, single Blind

Detailed Description

Open single-group Phase I study delivering three psilocybin dosing sessions integrated with structured psychotherapy. Preparatory contact includes at least one face-to-face and one telehealth session (total ~6–8 hours) before first dose; dosing sessions last approximately 6–8 hours and are supervised by clinical staff.

Dosing schedule: session 1 = 1 mg, sessions 2 and 3 = 25 mg each, spaced two weeks apart; participant is blinded to dose. Outcomes include change in core eating-disorder psychopathology (EDE/EDE‑Q), depression (BDI‑II), with baseline, 6‑week post‑first dose, monthly to 6 months and 12‑month follow-up assessments.

Study Protocol

Preparation

2 sessions
420 min each

Dosing

3 sessions
420 min each

Integration

3 sessions

Therapeutic Protocol

Manualized psychotherapy included

Study Arms & Interventions

Psilocybin + therapy

experimental

Three oral psilocybin dosing sessions integrated with preparatory and integration psychotherapy; participant single-blind to dose.

Interventions

  • Psilocybin25 mg
    via Oral• every 2 weeks• 3 doses total

    Session doses: 1 mg (session 1), 25 mg (sessions 2 and 3); participant blinded to dose; psychotherapy provided; administered by nurse practitioner and clinical psychologist.

Participants

Ages
21 – 65
Sexes
female

Inclusion Criteria

  • Female patients aged 21+ years
  • Meet criteria for AN as per DSM-5 criteria
  • BMI greater than or equal to 14kg/m2
  • > 3 years of illness duration
  • Current/ past treatments have not maintained remission
  • Referral from care team (psychiatrist or GP and clinician)
  • Agree to maintain contact with their care team
  • Identified support person
  • Agree to refrain from psychoactive drugs, nutritional or herbal supplements for at least 24 hours before each dose of psilocybin
  • Agree to a washout serotonergic medications if currently prescribed
  • Availability for the duration of the study
  • Agree to have research team maintain contact with an identified next-of-kin or support person (i.e. close friend) for the duration of the study
  • Capacity to consent
  • Sufficiently competent in English and mental capacity to provide written informed consent.

Exclusion Criteria

  • History of neurological conditions (e.g. epilepsy)
  • Schizophrenia or other psychotic disorders/bipolar disorder
  • First or second degree relative with psychotic disorder
  • Severe dissociative disorders
  • Diabetes
  • Cardiovascular disease
  • Uncorrected hypo- or hyperthyroidism
  • Abnormal serum electrolytes
  • Raised cardiac enzymes
  • Abnormal QT interval prolongation at screening or history of this
  • Hypertension
  • Hepatic or renal failure (e.g., CrCl < 30ml/min)
  • Drug or alcohol dependence in last 6 months
  • Prior allergy, hypersensitivity or adverse reaction to psychedelic substances
  • Emotionally unstable personality, or other psychiatric problem that may jeopardize therapeutic alliance or safety
  • Currently an involuntary patient
  • Patient being unsafe to manage on an outpatient basis
  • History of serious suicide attempts or presence of a suicide/ serious self-harm risk at screening
  • History of laxative abuse in the last 3 months
  • Unstable physical condition (e.g., weight loss > 2 kg in the prior month)
  • Pregnancy (negative pregnancy tests mandatory at screening visits, baseline, and psilocybin dosing sessions) or Nursing
  • If sexually active, participants who lack appropriate contraception
  • Patients currently or previously (past 3 months) enrolled in another clinical trial of an investigational product
  • No email/phone.

Study Details

  • Status
    Not yet recruiting
  • Phase
    Phase I
  • Type
    interventional
  • Design
    Non-randomizedsingle Blind
  • Target Enrollment30 participants
  • Timeline
    Start: 2023-07-01
    End: 2025-12-30
  • Compound
    Psilocybin
  • Topic
    Eating Disorders

Locations

Unknown facility — Australia

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