A Mechanistic Study to Assess a Single Dose of CYB003 in Participants With Depression and Anxiety

Many patients with MDD do not respond or have an incomplete response to treatment with currently available antidepressants. The use of psychedelics (e.g. psilocybin) is being investigated as a new approach to improve depressive symptomatology, however their mechanism of action is still not well understood. Psilocin is the active metabolite of psilocybin responsible for the psychedelic effects of the parent compound. CYB003 is a synthetic, deuterated isotopomer of psilocin, being developed by Cybin for the treatment of MDD. The study will investigate the changes in brain activity, connectivity, and microstructural neuroplasticity assessed using electroencephalography (EEG)/electromyography (EMG) and functional magnetic resonance imaging (fMRI)/ diffusion-weighted magnetic resonance imaging (DWI) after administration of one oral dose of CYB003. Up to 40 participants will be enrolled and randomized into two groups: one receiving 16 mg of CYB003, and one group receiving placebo. Psychological support will be provided before, during and after the administration session. Assessments performed at Baseline and on Day 2 and Day 21 after administration will include EEG/EMG, MRI, clinician (MADRS, HAM-A, C-SSRS) scales and self-report questionnaires to assess depression and anxiety symptoms, cognitive testing, self-report questionnaires to evaluate the psychedelic effects of CYB003 administration, and blood draw of the Gsα-AC biomarker assay.