Psilocybin vs Escitalopram for Major Depressive Disorder: Comparative Mechanisms

Brief Summary

This is a randomised double-blind clinical trial. The aim is to compare the efficacy and mechanisms of action of psilocybin, the primary psychoactive substance in 'magic mushrooms', with the SSRI (selective serotonin reuptake inhibitor) escitalopram for major depressive disorder (MDD).

Intervention / Treatment

  • Psilocybin + Placebo (DRUG)
    Multiple dosing days psilocybin vs 6 weeks of daily placebo
  • Psilocybin + Escitalopram (DRUG)
    Multiple dosing days psilocybin vs 6 weeks of daily escitalopram

Condition or Disease

  • Depressive Disorder, Major


  • Phase 2
  • Study Design

    Study type: INTERVENTIONAL
    Status: Unknown status
    Study results: No Results Available
    Age: 18 Years to 80 Years
    Enrollment: 59 (ACTUAL)
    Funded by: Other
    Allocation: Randomized
    Primary Purpose: Treatment


    • Participant
    • Investigator

    Clinical Trial Dates

    Start date: Jan 07, 2019 ACTUAL
    Primary Completion: Apr 17, 2020 ACTUAL
    Completion Date: Oct 01, 2020 ESTIMATED
    Study First Posted: Feb 12, 2018 ACTUAL
    Results First Posted: Aug 30, 2020
    Last Updated: Jul 30, 2020

    Sponsors / Collaborators

    Lead Sponsor: Imperial College London
    Lead sponsor is responsible party
    Responsible Party: N/A

    Participant Groups

    • Patients receive Psilocybin

    • Patients receive Escitalopram

    Eligibility Criteria

    Sex: All
    Minimum Age: 18
    Maximum Age: 80
    Age Groups: Adult / Older Adult
    Healthy Volunteers: Yes

    Inclusion Criteria:

    1. Major depressive disorder (DSM-IV)
    2. Depression of moderate to severe degree (17+ on the 21-item HAM-D).
    3. No MRI contraindications
    4. No SSRI contraindications
    5. Has a GP (general practitioner) or other mental healthcare professional who can confirm diagnosis
    6. 18-80 years of age
    7. Males and females
    8. Sufficiently competent with English language

    Key exclusion criteria:

    1. Current or previously diagnosed psychotic disorder
    2. Immediate family member with a diagnosed psychotic disorder
    3. Medically significant condition rendering unsuitability for the study (e.g., diabetes, epilepsy, severe cardiovascular disease, hepatic or renal failure e.g. CLRC \< 30 ml/min etc.)
    4. History of serious suicide attempts requiring hospitalisation.
    5. Significant history of mania (determined by study psychiatrist and medical records)
    6. Psychiatric condition judged to be incompatible with establishment of rapport with therapy team and/or safe exposure to psilocybin, e.g. borderline personality disorder
    7. Blood or needle phobia
    8. Positive pregnancy test at screening or during the study, women who are planning a pregnancy and/or women who are nursing/breastfeeding.
    9. Participants who do not agree to use an acceptable contraceptive method throughout their participation in study.
    10. Current drug or alcohol dependence
    11. No email access
    12. Use of contraindicated medication
    13. Patients presenting with abnormal QT interval prolongation at screening or with a history of this (QTc at screening above 440ms for men and above 470ms for women)

    Primary Outcomes
    • Change in blood oxygen level dependent (BOLD) signal during fMRI in response to emotional faces during an emotional faces paradigm done inside the fMRI scanner.

    Secondary Outcomes
    • Change in QIDS-SR16 (self-rated measure of depressive symptoms). Scale is composed of 16 items that correlate with the 9 DSM-IV symptom criteria for depression. Each response is graded 0-4 (none-severe symptoms). Questions 1-4 concern sleep disturbances, Question 5 addresses sad mood, Questions 6-9 appetite/weight, Question 10 concentration, Question 11 self-criticism, Question 12 suicidal ideation, Question 13 interest, Q14 energy/fatigue and Questions 15-16 psychomotor agitation/retardation. All questions that address the same topic are grouped and only the highest score from each group is summed up together with the other questions in order to produce a total score. Scores can range from 0-27 and depression severity is graded based on the total score in the following way: 1-5 = No depression 6-10 = Mild depression 11-15 = Moderate depression 16-20 = Severe depression 21-27 = Very severe depression

    More Details

    NCT Number: NCT03429075
    Acronym: Psilodep-RCT
    Other IDs: 17HH3790
    Study URL:
    Last updated: Sep 29, 2023