PSIL201 Long-term Follow-up Study: Psilocybin or Niacin / Major Depressive Disorder

A One-Year Observational Follow-up Study of Participants With Major Depressive Disorder Following a Randomized, Double-Blind Single-Dose of Psilocybin or Niacin-Control

Status

Terminated

Phases

Unknown

Study type

Observational

Source

ClinicalTrials.gov

Registry ID

NCT04353921

Enrollment

Registered

2020-04-21

Start date

2020-06-30

Completion date

2022-10-18

Last updated

2026-05-04

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Major Depressive Disorder

Brief summary

This is a Phase 2 double-blind, long-term observational follow-up study of participants from Study PSIL201. Participants providing informed consent were enrolled into this study and completed web surveys and telephone interviews conducted by one central site at the following time intervals: months 3 and 6 (± 7 days for each assessment) and months 10 and 12 (± 14 days for each assessment).

Interventions

OTHERNo intervention will be administered as part of this study.

No intervention will be administered as part of this study.

Study design

Observational model

COHORT

Time perspective

OTHER

Eligibility

Sex/Gender

ALL

Age

21 Years to 65 Years

Healthy volunteers

Inclusion criteria

* Enrollment and randomization in Study PSIL201 * Ability and willingness to provide informed consent prior to initiation of any study-related procedures

Exclusion criteria

* Inability or unwillingness to complete study procedures, including regular completion of web surveys and telephone interviews with study personnel

Design outcomes

Primary

Measure	Time frame	Description
Montgomery-Asberg Depression Rating Scale	6 Months post-dosing in PSIL201	Between-group difference in mean change from baseline (prior to dosing in PSIL201) in Montgomery-Asberg Depression Rating Scale (MADRS) to 6 months post-dosing in Study PSIL201

Countries

United States

Contacts

STUDY_DIRECTORCharles Raison, MD

Usona Institute

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: May 5, 2026