This is a phase II, multi-centre, randomised, double-blind, controlled study. The study population will include participants aged ≥18 years with Major Depressive Disorder (MDD) with one prior treatment failure of an antidepressant in their current depressive episode.~Overall, 102 participants will be randomised in a 2:1 ratio to receive COMP360 25 mg or COMP360 1 mg.~In this study the aim is to investigate the safety and tolerability of COMP360, administered with psychological support, in adult participants with MDD with one prior treatment failure. In addition, pharmacokinetics and efficacy of COMP360 will be investigated.~The study will last up to 16 weeks including a three- to ten-week Screening Period and a six-week follow-up from investigational product (IP) administration.
Safety, Tolerability, pharmacokinetics and efficacy of a single administration of COMP360 in participants with Major Depressive Disorder with one prior treatment failure.