Skip to content

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

A clinical trial to assess safety and efficacy of psilocybin-assisted psychotherapy for treatment-resistant anorexia nervosa in adults

Status
Recruiting
Phases
Phase 1
Study type
Interventional
Source
ANZCTR
Registry ID
ACTRN12623000357651
Enrollment
1
Registered
2023-04-06
Start date
2025-10-26
Completion date
2027-10-24
Last updated
2026-02-16

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

None listed

Brief summary

This study aims to: 1. Demonstrate safety and preliminary efficacy of psilocybin-assisted psychotherapy in reducing core eating disorder psychopathology and increasing motivation to change in AN as assessed by the EDE/EDE-Q and RMQ 2. Evaluate effects of psilocybin on depressive, anxious and obsessional symptoms, cognitive flexibility, quality of life and alliance between therapist and patient.

Interventions

The intervention will involve 3 oral doses of psilocybin embedded with psilocybin-assisted psychotherapy (talk therapy). Consisting of at least 1 face-to-face and 1 telehealth preparatory sessions (overall 6-8 hours) prior to first dose, supervision during 3 dosing sessions and 3-post dosing integration sessions. Each participant will receive a total of three psilocybin sessions, each session spaced two weeks apart, with 1 mg in session 1 and 25 mg in sessions 2 and 3. Only the participant will

The intervention will involve 3 oral doses of psilocybin embedded with psilocybin-assisted psychotherapy (talk therapy). Consisting of at least 1 face-to-face and 1 telehealth preparatory sessions (overall 6-8 hours) prior to first dose, supervision during 3 dosing sessions and 3-post dosing integration sessions. Each participant will receive a total of three psilocybin sessions, each session spaced two weeks apart, with 1 mg in session 1 and 25 mg in sessions 2 and 3. Only the participant will be blind to dose, knowing only that they may receive maximum 25 mg in any session. Dosing sessions will last 6-8 hours and will be administered by a nurse practitioner and clinical psychologist. Examples of specific content/topics that will be discussed during the dosing sessions will be specific to the participant. During dosing sessions contact is kept to a minimum to encourage participants to explore their own mental state.

The intervention will involve 3 oral doses of psilocybin embedded with psilocybin-assisted psychotherapy (talk therapy). Consisting of at least 1 face-to-face and 1 telehealth preparatory sessions (overall 6-8 hours) prior to first dose, supervision during 3 dosing sessions and 3-post dosing integration sessions. Each participant will receive a total of three psilocybin sessions, each session spaced two weeks apart, the maximum dose will be 25 mg in any session. Dosing sessions will last 6-8 ho

The intervention will involve 3 oral doses of psilocybin embedded with psilocybin-assisted psychotherapy (talk therapy). Consisting of at least 1 face-to-face and 1 telehealth preparatory sessions (overall 6-8 hours) prior to first dose, supervision during 3 dosing sessions and 3-post dosing integration sessions. Each participant will receive a total of three psilocybin sessions, each session spaced two weeks apart, the maximum dose will be 25 mg in any session. Dosing sessions will last 6-8 hours. The psilocybin will be administered by the study psychiatrist. The information about the dosage is hidden as the study is single blind. The dosage will become publicly available when the recruitment numbers have been reached and all participants have finished the study up until 12-month follow-up. Eligible participants for the neuroimaging component will also do an EEG and MRI at baseline and 6-weeks end point. Examples of specific content/topics that will be discussed during the dosing sessions will be specific to the participant. During dosing sessions contact is kept to a minimum to encourage participants to explore their own mental state.

Sponsors

University of Sydney
Lead SponsorUniversity

Study design

Allocation
Non-randomised trial
Intervention model
Single group
Primary purpose
Treatment
Masking
Blinded (masking used) (Subject)

Eligibility

Sex/Gender
All
Age
21 Years to 65 Years
Healthy volunteers
No

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 e.g. • 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.

Outcome results

None listed

Source: ANZCTR · Data processed: Feb 19, 2026