Multicentre Study To Assess Safety And Efficacy Of Psilocybin In Patients With Treatment-Resistant Depression Following Completion Of COMP001 And COMP003 Trials (P-TRD LTFU)

The primary objective of this study is to assess the long-term efficacy of psilocybin with respect to use of new antidepressant treatment, hospitalisations for depression, suicidality, and depressive severity rated using the Montgomery and Asberg Depression Rating Scale (MADRS) over a total of 52 weeks (compared across the 1 mg, 10 mg and 25 mg psilocybin groups from COMP001). In this present study (COMP004), the aim is to follow up participants from COMP001 and COMP003 in a long-term follow up study, with both remote and digital assessments, to explore the long term efficacy and safety of the three different doses of psilocybin (1 mg, 10 mg, and 25 mg) administered to patients with TRD as a monotherapy in COMP001 and 25 mg psilocybin administered as an adjunct to an SSRI in COMP003. Patients previously treated in COMP001 will be followed for approximately 40 weeks and patients previosuly treated in COMP003 will be followed for approximately 49 weeks giving a total follow up period of 52 weeks from psilocybin dosing.