Psilocybin-assisted therapy for the treatment of resistant major depressive disorder (PsiDeR): protocol for a randomised, placebo-controlled feasibility trial

Introduction Psilocybin-assisted therapy may be a new treatment for major depressive disorder (MOD), with encouraging data from pilot trials. In this trial (short name: PsiDeR) we aimed to test the feasibility of a parallel-group, randomised, placebo-controlled design. The primary outcomes in this trial are measures of feasibility: recruitment rates, dropout rates and the variance of the primary outcome measure of depression. Methods and analysis We are recruiting up to 60 participants at a single centre in London, UK who are unresponsive to, or intolerant of, at least two evidence-based treatments for MDD. Participants are randomised to receive a single dosing session of 25 mg psilocybin or a placebo. All participants receive a package of psychological therapy. The primary outcome measure for depression is the Montgomery Asberg Depression Rating Scale collected by blinded, independent raters. The primary endpoint is at 3 weeks, and the total followup is 6 weeks. With further informed consent, this study collects neuroimaging and omics data for mechanism and biomarker analyses and offers participants an open label extension consisting of a further, open label dose of 25 mg of psilocybin.

Automated summary

Psilocybin-assisted therapy is being explored as a potential new treatment for major depressive disorder, with a trial in London testing the feasibility of the treatment in unresponsive or intolerant patients. The study aims to evaluate recruitment rates, dropout rates, and primary outcome measures of depression, with participants randomized to receive psilocybin or a placebo dose along with psychological therapy.