Study protocol of an open-label proof-of-concept trial examining the safety and clinical efficacy of psilocybin-assisted therapy for veterans with PTSD
Open accessAbstract
Introduction: Psilocybin-assisted therapy has shown significant promise in treating the cluster of mood and anxiety symptoms that comprise post-traumatic stress disorder (PTSD) but has yet to be tested specifically in this condition. Furthermore, current pharmacological and psychotherapeutic treatments for PTSD are difficult to tolerate and limited in efficacy, especially in the US Military Veteran (USMV) population. This open-label pilot study will examine the safety and efficacy of two psilocybin administration sessions (15 mg and 25 mg), combined with psychotherapy, among USMVs with severe, treatment resistant PTSD. Methods and analysis: We will recruit 15 USMVs with severe, treatment resistant PTSD. Participants will receive one low dose (15 mg) and one moderate/high dose (25 mg) of psilocybin in conjunction with preparatory and post-psilocybin therapy sessions. The primary safety outcome will be the type, severity and frequency of adverse events and suicidal ideation/behaviour, as measured by the Columbia Suicide Severity Rating Scale. The primary outcome measure for PTSD will be the Clinician Administered PTSD Scale-5. The primary endpoint will be 1 month following the second psilocybin administration session, and the total follow-up time will be 6 months. Ethics and dissemination: All participants will be required to provide written informed consent. The trial has been authorised by the Ohio State University Institutional Review Board (study number: 2022H0280). Dissemination of results will occur via a peer-reviewed publication and other relevant media. Trial registration number: NCT05554094 .
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A sample size of 15 was selected, consistent with pilot conventions and prior studies of PAT.
“A sample size of 15 was selected, consistent with pilot conventions when providing descriptive analysis of safety and feasibility in a clinical population and prior studies of PAT [19,20].”
From Psilocybin‐assisted psychotherapy for methamphetamine use disorder: A pilot open‐label safety and feasibility study. (2025) · cites this paper as [20]
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- Authors
- Davis, A. K., Levin, A. W., Nagib, P. B., Armstrong, S. B., & Lancelotta, R. L.
- Affiliations
- Johns Hopkins University (US)
- The Ohio State University (US)
- Center for Psychedelic Drug Research and Education, The Ohio State University College of Social Work, Columbus, Ohio, USA
- Corresponding author
- Davis, Alan K
- Venue
- BMJ Open
- Publisher
- BMJ
- Published
- 2023-05
- Volume
- 13
- Issue
- 5
- Pages
- e068884
- ISSN
- 2044-6055 (ISSN-L)
- PMC
- PMC10163450
- OpenAlex
- W4372336620
- Cited by
- 21
- References
- 35
- Citations by year
- 2026: 5 · 2025: 8 · 2024: 4 · 2023: 4
- FWCI
- 6.10
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Licence
- Locations
- BMJ Open (publishedVersion, cc-by-nc)
- PubMed Central (publishedVersion, cc-by-nc)
- PubMed (publishedVersion)
- DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
- Funders
- Center for Psychedelic Drug Research and Education (NA)
- Topics
- Social Sciences › Psychology › Clinical Psychology › Psychedelics and Drug Studies
- Social Sciences › Psychology › Clinical Psychology › Posttraumatic Stress Disorder Research
- Social Sciences › Psychology › Clinical Psychology › Psychotherapy Techniques and Applications
- Keywords
- psilocybin-assisted therapy, post-traumatic stress disorder, veterans, treatment-resistant PTSD, psychedelic therapy, adverse events, suicidal ideation, psychotherapy, dose comparison, treatment efficacy and safety
- MeSH terms
- Humans, Pilot Projects, Psilocybin, Stress Disorders, Post-Traumatic, Veterans, Treatment Outcome
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