PSIPET - The Effect of Psilocybin on MDD Symptom Severity and Synaptic Density

A Single Dose, Randomized, Double-Blind, Placebo-Controlled Phase II Positron Emission Tomography Study.

About the Study

PSIPET is a randomized, double-blind, placebo-controlled phase II trial that examine the efficacy of psilocybin as treatment for depression. It includes 30 participants and is the first study of its kind in Sweden.

In the study, the effect of a single dose of synthetic psilocybin together with psychological support is compared with the effect of a single dose of an active placebo together with psychological support. Both the effect on depression symptoms, and on potential biomarkers for depression and a proposed psilocybin mechanism of action are of interest. The aim of the study is to increase the understanding of biologically based causes of depression, and thus enable more effective treatments, and to increase specific knowledge about psilocybin treatment of depression.

For each patient, all treatment sessions are conducted together with the same two licensed psychologists according to a special manual. To evaluate the effect and increase the understanding of treatment, all patients are assessed before, during and after treatment using psychiatric assessment, assessment forms, magnetic resonance imaging (MRI), sampling of blood and spinal fluid, and positron emission tomography (PET).

The study is a collaboration between Karolinska Institutet (KI), Region Stockholm and Usona Institute. I is approved by The Swedish Medical Products Agency and the Swedish Ethical Review Authority. The principal entity is Norra Stockholms Psykiatri, Stockholms läns sjukvårdsområde (SLSO).