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 COMP 001).
This prospective, observational long-term follow-up (COMP 004) follows participants from COMP 001 and COMP 003 to assess efficacy and safety of three psilocybin dosing regimens (1 mg, 10 mg, 25 mg) over a 52-week period using remote and digital assessments.
Participants previously treated in COMP 001 are followed for approximately 40 weeks and those from COMP 003 for approximately 49 weeks, yielding up to 52 weeks of follow-up from psilocybin dosing; outcomes include new antidepressant use, hospitalisations for depression, suicidality and MADRS scores.
The study uses remote/digital data collection and includes multiple international sites; planned target was 150 with 66 participants recorded as actual enrollment in the registry fragment.
This one-year observational follow-up study (n=66) examined the long-term outcomes of psilocybin (25 mg, 10 mg, 1 mg; COMP360) in treatment-resistant depression (TRD). Median time to depressive relapse was longest in the 25 mg group (92 days) compared to 10 mg (83 days) and 1 mg (62 days), with most participants relapsing by week 12. A post hoc analysis of those entering the follow-up study (n=58) found a more pronounced difference, with the 25 mg group maintaining benefits for 189 days. Adverse events were minimal, with one case of mild suicidal ideation in the 1 mg group.