Dry extract from Psilocybe cubensis (15‑25:1) with methanol for adults with treatment‑resistant anorexia nervosa: a randomized, active‑placebo, triple‑blind trial

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What is this study about?

Anorexia nervosa is an eating disorder marked by very low body weight, a strong fear of gaining weight, and a distorted view of one’s own shape. The study examines a single oral dose of 25 mg of a dry extract from psilocybe cubensis (a mushroom‑derived substance) taken in capsules, combined with a psychological approach called acceptance and commitment therapy, which helps participants develop healthier thoughts and actions about food and body image.

The purpose of the study is to evaluate the effect of psilocybin on symptoms of the disorder. Participants receive the medication under supervision, attend several therapy sessions over a period of weeks, and return for follow‑up visits to track any changes. The trial follows a randomised, triple‑blind design, meaning participants are assigned by chance and neither the participants, the clinicians, nor the data analysts know who receives the active medication or the active‑placebo, ensuring unbiased results.

1 enrollment confirmation

after joining the study you receive written information about the trial and sign a consent form confirming your participation.

2 baseline assessment

a series of assessments are performed to record your current health status, including questionnaires about eating habits, weight measurements, and basic laboratory tests.

these results serve as the reference point for all later comparisons.

3 randomization

you are randomly assigned to receive either the study medication or an active placebo, without knowing which one you receive.

4 pre‑treatment therapy sessions

you attend several sessions of acceptance and commitment therapy (act), a type of counseling that helps you develop coping strategies before receiving the medication.

5 medication administration

on a scheduled day you take one oral capsule containing 25 mg of a dry extract from psilocybe cubensis (a type of mushroom).

the capsule is swallowed with water under the supervision of study staff.

6 post‑dose observation

after taking the capsule you remain in a comfortable, quiet room for several hours while staff monitor your safety and well‑being.

you may be offered light snacks and water, and you are encouraged to rest.

7 integration therapy sessions

following the observation period you attend additional act sessions that help you understand and integrate the experience from the medication into everyday life.

8 primary follow‑up (10 weeks)

ten weeks after the baseline assessment you complete the same questionnaires and measurements as at the start.

these data are used to evaluate the primary outcome of the trial.

9 secondary follow‑up (22 weeks)

twenty‑two weeks after the baseline assessment you repeat the assessments again.

these results are used to evaluate the secondary outcome of the trial.

10 study completion

after the final follow‑up you receive a summary of your individual results and the study concludes for you.

Who Can Join the Study?

  • Female gender – you must be a woman.
  • Age between 18 and 50 years, including both 18 and 50.
  • Diagnosis of Anorexia Nervosa or Atypical Anorexia Nervosa as defined by the ICD-11 (the international system used to classify health conditions).
  • No known allergy to any of the ingredients in the study medication (an allergy is a reaction that can cause symptoms like rash, swelling, or trouble breathing).
  • Current treatment has not worked well enough, with at least one standard psychotherapy (talk therapy) having failed, as judged by the study doctor.
  • Willing and able to stop other psychiatric medicines, except for benzodiazepines (a type of medication that helps with anxiety or sleep) and SSRIs (a class of antidepressants).

Who Cannot Join the Study?

  • Having current or past psychotic symptoms (such as hearing voices or believing things that are not true).
  • Having close family members (first-degree relatives like parents, siblings, or children) who have a history of psychotic symptoms.
  • Having a body‑mass index (BMI) of 15 or lower, which means very low body weight.
  • Being at an immediate or serious risk of suicidality (thoughts or actions related to suicide).
  • Having used psychedelics such as LSD, psilocybin, or DMT within the last two years.
  • Having other serious medical problems that need regular strong medicines (systemic medications).
  • Having epilepsy (a condition that causes repeated seizures) or a history of seizures.

Where you can join this trial?

Verified and Recommended Sites

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Verified Sites

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Other Sites

Site Name City Country Status
Region Sjaelland Holbæk Denmark

Want to learn more about this study or check if you can participate? Contact us.

Trial status

Country Status Recruitment Start
Denmark Denmark
Not yet recruiting
01.06.2026

Trial locations

PEX010 is a capsule that contains a dry extract from the mushroom *Psilocybe cubensis*. This extract provides psilocybin, a substance that can temporarily change how the brain processes thoughts and emotions. In the study, participants take the capsule before therapy sessions to see if psilocybin can help reduce the severe thoughts and behaviors associated with anorexia nervosa. The researchers are testing whether this single dose can improve the participants’ mood, eating patterns, and overall mental health compared with an active placebo.

Acceptance and Commitment Therapy (ACT) is a type of psychological counseling that helps people learn to accept difficult thoughts and feelings without trying to fight them, while also encouraging actions that are in line with their personal values. In this trial, ACT is delivered after the participant has taken the psilocybin capsule. The therapy aims to support patients in applying the insights gained during the psilocybin experience to make healthier choices around food, body image, and self‑care, ultimately working toward lasting recovery from anorexia nervosa.

Investigated Diseases:

Anorexia nervosa – Anorexia nervosa is an eating disorder marked by an extreme fear of gaining weight and a persistent desire to be thin. People with the condition severely limit their food intake, leading to a steadily decreasing body weight. Over time, the restriction becomes more rigid, and some may develop episodes of binge eating followed by attempts to compensate. The ongoing calorie deficit gradually affects physical functions such as heart rate, hormone balance, and bone health.

Trial ID:
2025-524939-39-02
Trial Phase:
Therapeutic exploratory (Phase II)

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