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Study on Psilocybin for Patients with Treatment-Resistant Depression

Verified siteInvestigationalNo placebo
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What is this trial about?

A plain-language summary of the goals, design and what participants do

This clinical trial is focused on studying the effects of a treatment for depression, specifically in cases where the condition has not improved with other treatments. The treatment being tested is a substance called psilocybin, which is administered in the form of a capsule taken by mouth. The purpose of the study is to explore how psilocybin affects certain brain activities related to how effort is assessed, which may provide insights into its potential benefits for individuals with treatment-resistant depression.

Participants in the study will receive psilocybin and undergo brain scans using a technique called fMRI (functional Magnetic Resonance Imaging) to observe changes in brain activity before and after the treatment. The study will also monitor changes in depression symptoms and overall mood over time, with assessments conducted at various intervals, including the start of the study, four days later, and then one and three months after treatment. Additionally, participants will provide feedback on their experience during the treatment sessions, including any side effects or issues with tolerance.

The study aims to gather valuable information on how psilocybin might help improve symptoms of depression by examining both brain activity and changes in mood and behavior. This research could potentially lead to new treatment options for those who have not found relief with existing antidepressant medications.

The research process

The trial runs in 6 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial assessment

    The patient undergoes an initial assessment to confirm eligibility for the study. This includes a clinical evaluation to verify a diagnosis of moderate or severe depression without psychotic features, confirmed by a MINI interview and QIDS score.

    The patient must have a history of not responding to at least two different antidepressant treatments, be between 25 and 60 years old, and be in good physical health without unstable medical conditions.

  2. Step 2

    Consent and preparation

    The patient provides informed consent to participate in the study. This involves understanding the study's purpose, procedures, and potential risks.

    The patient is prepared for the study, which includes ensuring they can speak and understand French easily and are available for a 6-month follow-up period.

  3. Step 3

    Baseline measurements

    Baseline measurements are taken, including brain activity using fMRI in specific regions involved in effort assessment, such as the basolateral amygdala and dorsal anterior cingulate cortex.

    Depression scores are recorded using the Quick Inventory of Depressive Symptomatology (QIDS) and other relevant scales.

  4. Step 4

    Psilocybin administration

    The patient receives a dose of psilocybin in the form of a capsule for oral use. The specific dosage and frequency are determined by the study protocol.

    The administration session is monitored, and the patient's experience is evaluated using the 5-Dimensional Altered States of Consciousness Questionnaire.

  5. Step 5

    Post-treatment assessment

    Following the administration of psilocybin, the patient undergoes further assessments to measure changes in brain activity and depression scores.

    These assessments occur at multiple time points: 4 days, 1 month, and 3 months after treatment.

  6. Step 6

    Follow-up and evaluation

    The patient participates in follow-up evaluations to assess the long-term effects of the treatment on depression symptoms and overall satisfaction with the therapy.

    The study collects data on any adverse events or tolerance issues reported by the patient during the follow-up period.

Who can join the trial?

10 criteria

  • Patient with a **DSM-IV diagnosis** of a current moderate or severe depressive episode without psychotic features. This means a doctor has diagnosed the patient with a certain level of depression, but they do not have symptoms like hallucinations or delusions.
  • Patient must have health insurance or be part of a health insurance plan.
  • Patient has not improved after trying at least two different types of antidepressant medications for at least six weeks each.
  • Patient has a score greater than 10 on the **QIDS scale**, which is a questionnaire used to measure the severity of depression.
  • Patient is aged 25 years or older but younger than 60 years.
  • Patient is available for follow-up visits for six months.
  • Patient is in good physical health and does not have any unstable medical conditions. These conditions include heart problems, certain types of diabetes, severe liver issues, and other specific health problems.
  • Patient can speak and understand French easily.
  • Patient has given their free and informed consent, meaning they understand the study and agree to participate.
  • Patient has signed the consent form, which is a document that confirms their agreement to join the study.

Who cannot join the trial?

6 criteria

  • Individuals with a history of **severe mental disorders** other than depression. This means if you have had serious mental health issues, you may not be able to participate.
  • People who are currently taking medications that could interfere with the study. This means if you are on certain drugs, it might affect the study results.
  • Pregnant or breastfeeding women. This is to ensure the safety of both the mother and the baby.
  • Individuals with a history of **substance abuse**. This refers to the misuse of drugs or alcohol.
  • People with certain medical conditions that could affect the study. This means if you have specific health issues, it might not be safe for you to participate.
  • Anyone who has participated in another clinical trial recently. This is to avoid any interference with the results of this study.
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Investigated drugs

Psilocybin is a substance being studied for its potential effects on depression that does not respond to traditional treatments. In this trial, researchers are examining how psilocybin affects brain activity, particularly the neural circuits involved in evaluating effort. The goal is to understand if psilocybin can help improve symptoms in people with treatment-resistant depression by altering brain function.

What is already known about the treatment

Psilocybin – Psilocybin is typically administered orally, often in the form of capsules or tablets. It is currently being studied in clinical trials for its potential use in treating depression and other mental disorders. The main therapeutic indication for psilocybin is treatment-resistant depression. At the molecular level, psilocybin works by interacting with serotonin receptors in the brain, which can alter mood and perception. It is classified pharmacologically as a psychedelic compound.

Investigated diseases

  • Depression

    Depression is a common mental health disorder characterized by persistent feelings of sadness, hopelessness, and a lack of interest or pleasure in activities. It can affect a person's thoughts, behavior, and overall well-being. Symptoms may include changes in appetite, sleep disturbances, fatigue, difficulty concentrating, and feelings of worthlessness or guilt. The severity and duration of symptoms can vary, and they may interfere with daily functioning. Depression can occur at any age and often requires a comprehensive approach to management.

  • Mental Disorders

    Mental disorders encompass a wide range of conditions that affect mood, thinking, and behavior. These disorders can include anxiety disorders, mood disorders, psychotic disorders, and personality disorders, among others. Symptoms vary depending on the specific disorder but may involve emotional instability, cognitive dysfunction, and difficulties in social interactions. Mental disorders can impact daily life and relationships, and they often require a combination of therapeutic strategies for management. The progression of these disorders can differ significantly from one individual to another.

Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IITrial ID2022-501092-11-00Protocol codeNIMAO/2021-2/JLC-01Estimated enrolment20 patientsSponsorCentre Hospitalier Universitaire De Nimes

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