Psilocybin TRD Feasibility RCT

This randomised, placebo-controlled trial (n=60) investigated the effects of psilocybin in participants aged 25 to 80 with treatment-resistant depression (TRD).

It aimed to assess the feasibility of conducting a larger trial, gather safety data, and estimate the necessary sample size. Participants had to meet specific criteria, including failing to respond to multiple antidepressants and psychotherapy sessions.

The study is a double-blind, placebo-controlled phase with 60 participants. The primary outcome measures were safety and efficacy in reducing depression symptoms over an 8-week period.

The trial was conducted from December 3, 2020, to February 28, 2024, in several locations in London, UK, sponsored by King’s College London and funded by NIHR Academy.

Trial Details

Major depressive disorder is a burdensome and costly health problem for patients, carers, societies and governments. Resistance to medical and psychological treatments is common and this group are much more likely to be socioeconomically inactive, suffer from comorbid physical health problems and to die by suicide. Despite this, treatment resistant depression is under-researched and no new breakthrough paradigms of treatment have been developed since the introduction of the selective serotonin antidepressants and cognitive behavioural therapy in the 1980s. Combinations of antidepressants and psychotherapy are more effective than either alone. The psychedelic drugs, including psilocybin, were used by psychiatrists prior to prohibition in 1970 for treatment resistant cases of depression, anxiety and addictions. Within a supportive therapeutic context they showed promise in this group, however evidence about safety and efficacy was inconclusive prior to prohibition. Since 2010 a resurgence of interest in this treatment paradigm has occurred. We have completed an uncontrolled, open-label pilot study of psilocybin with psychological support in 20 patients with treatment resistant depression that demonstrated the feasibility of delivering this treatment in this group of patients. The current study is a randomised, placebo controlled trial of psilocybin in up to 60 participants with treatment resistant depression. The objective is to test the feasibility of the randomised, controlled trial design with this drug in this patient group, to collect safety data and to estimate how many participants we would need for a larger, definitive trial.

Trial Number

Data attribution

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