UK Trial Finds Promising Results for Psilocybin in Treatment-Resistant Depression
A new UK clinical trial has reported promising results for psilocybin-assisted therapy in people living with treatment-resistant depression.
The study, led by researchers at King’s College London in partnership with South London and Maudsley NHS Foundation Trust, is the first publicly funded randomised controlled trial of psilocybin for depression delivered within an NHS setting in England.
The findings were published in Nature Medicine in August 2026.
What did the trial investigate?
The study, known as the Psilocybin in Depression Resistant to Standard Treatments (PsiDeR) trial, involved 60 participants with treatment-resistant depression. Participants had experienced depression that had not responded adequately to at least two previous treatments.
Half of the participants received a 25 mg dose of psilocybin, while the other half received a true placebo containing no psilocybin. Both groups also received psychological support as part of the trial.
Importantly, the study used a randomised and blinded design, allowing researchers to compare outcomes between the psilocybin and placebo groups.
Promising differences in depression symptoms
Researchers reported a significantly greater reduction in depression scores among participants who received psilocybin compared with those who received placebo.
At three weeks, 43% of participants in the psilocybin group met the study’s criteria for treatment response. This increased to 50% at six weeks.
By comparison, just 3% of participants in the placebo group met the treatment-response threshold at both time points.
The study also reported differences in remission rates. At three weeks, 40% of participants in the psilocybin group met the criteria for remission, compared with 3% in the placebo group. This difference remained at six weeks.
Why this study matters
One of the important aspects of the research is that it was publicly funded and conducted within an NHS-linked setting.
Rather than focusing only on highly selected participants in specialist commercial research environments, the trial was designed to include people with a broader history of treatment-resistant depression.
Researchers also explored whether psilocybin could be administered in a community-based clinical research environment rather than exclusively within a hospital.
According to the research team, the community setting provided a calm and supportive environment with trained staff, and no new safety concerns were identified during the study.
The results still need to be interpreted carefully
Although the findings are encouraging, the researchers emphasise that further research is needed.
The trial was relatively small, involving 60 participants, and responses to treatment varied considerably between individuals.
The researchers also noted that most participants were able to guess whether they had received psilocybin or placebo. This means that expectations surrounding the treatment may have influenced some of the differences observed between the groups.
The study therefore does not establish psilocybin as an approved treatment for depression. Larger clinical trials will be needed to further investigate its effectiveness, safety, cost-effectiveness and potential role within healthcare systems.
A growing area of psilocybin research
The findings add to a growing body of research investigating psilocybin and other psychedelic compounds for mental health conditions.
King’s College London has been involved in several clinical research programmes examining psilocybin, including studies investigating treatment-resistant depression and other mental health conditions.
The latest trial is particularly notable because it demonstrates that a randomised controlled study of psilocybin can be conducted within a publicly funded NHS research environment.
As research continues, future studies will help determine whether psychedelic-assisted therapies could eventually have a role in mainstream mental healthcare.
Source and further reading
This article is based on research reported by King’s College London in its news report, “Promising results from first UK trial of psilocybin for depression”, published on 6 August 2026.
The original study was published in Nature Medicine as “Psilocybin-assisted therapy for treatment-resistant major depressive disorder in a public healthcare setting: a randomized controlled trial.”
Read the original report from King’s College London
This article is provided for research and educational purposes. It does not constitute medical advice or recommend the use of psilocybin or other controlled substances.
