Information for Clinicians


(Psi)locybin in (De)pression (R)esistant to standard treatments:

A randomised, placebo controlled trial.

Inclusion Criteria

  • Current diagnosis of major depressive disorder
  • Currently moderately-severely depressed
  • Have failed 1 or more antidepressants and/or NICE recommended psychological therapy
  • Aged between 25 and 80
  • Willing to stop current medical treatments for depression
  • Willing and able to consent
  • Willing to complete assessments and complete study visit

Trial Details

Chief Investigator: Prof Allan Young
Principal Investigator: Dr James Rucker
Research Assistant: Tim Mantingh
Sample size: 60 participants
Trial type: RCT Funder: NIHR
Trial start: late 2019 Trial end: late 2022
Location: King’s College Hospital Clinical
Research Facility, Denmark Hill, London, SE5 9RS 

More information

For more information, please continue reading. To refer participants or if you are interested to help the study team then email us: at

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PsiDeR Trial Description

We are recruiting up to 60 adult participants with treatment resistant depression to take part in a randomised, double blind, placebo-controlled trial of up to 2 doses of psilocybin given in a supportive hospital setting at King’s College Hospital.

Psychological and psychiatric support will be given before, during and after treatment. Current depression treatments will be tapered off by a study psychiatrist prior to treatment. During this time participants will be given psychoeducation and meet a therapist who will support them through the trial.

Initially, participants will receive a single dose of either psilocybin or placebo given at the Clinical Trials Facility at King’s College Hospital.

Participants will return home after treatment. Follow up will be for 6 weeks with telephone and face to face meetings. We will also ask participants to have a brain scan, perform cognitive tests and donate blood samples before and after treatment.

After 6 weeks of follow up all participants will be offered a further, open label dose of 25mg of psilocybin (unless there is a clinical reason not to), with a further 3 months of follow up. Please note that most people who volunteer for this study will, for one reason or another, turn out not to be eligible. The study team reserve the right to exclude participants who we do not feel can be safely exposed tot his experimental treatment.


We cannot accept participants who:

• Are desperate to receive psilocybin
• Are likely to deteriorate if they are on a waiting
• Are a high risk to themselves or others
• Have ongoing drug and alcohol problems
• Are homeless or socially unstable
• Don’t have a social support network
• Can’t easily get to the hospital
• Are looking for a ‘quick fix’ for their depression.

This is not how this treatment works

Those who may be suitable include:

• Those who have responded incompletely to medical or psychological treatment for depression, discontinued due to unacceptable side effects (or both).

• Those who appear psychologically ‘stuck’ in psychotherapy or unable to process a difficult or traumatic life event despite adequate support.

• Those who want to receive psilocybin therapy.

All appointments will take place at King’s College Hospital during usual office hours. We will pay reasonable travel expenses but cannot fund hotel accommodation or other expenses.

Participants will not be paid for participation in this trial. All referrers will be participation. We are unable to provide crisis services.

Schedule of Visits