Investigating the safety and tolerability of single-dose psilocybin for post-traumatic stress disorder: A nonrandomized open-label clinical trial

This Phase II, nonrandomized open-label trial (n=22) tested a single 25 mg dose of psilocybin with psychological support in adults with PTSD. It found the treatment to be safe and well-tolerated, with common side effects such as headache, nausea, crying, and fatigue resolving quickly. Clinically meaningful reductions in PTSD symptoms were observed at weeks 4 and 12, alongside improvements in functioning and quality of life.

Abstract of Investigating the safety and tolerability of single-dose psilocybin for post-traumatic stress disorder

Background: Post-traumatic stress disorder (PTSD) is a debilitating condition for which there are few efficacious treatments. Psilocybin is being studied for use in treatment-resistant depression but has not yet been investigated in PTSD.

Aims: The trial’s primary outcome was to investigate the safety and tolerability of single-dose psilocybin in participants with PTSD.

Methods: This was a Phase 2, nonrandomized, open-label, multicenter trial. Secondary outcomes were changes in PTSD symptoms (Clinician-Administered PTSD Scale for DSM-5 (CAPS-5); PTSD Checklist for DSM-5 (PCL-5)), functional impairment (Sheehan Disability Scale; SDS) and quality of life (EQ-5D-5L index score).

Results: Amongst the 22 participants enrolled (63.6% female; mean (SD) age, 39.0 (7.91) years), there was a total of 117 treatment-emergent adverse events (TEAEs); 70 (59.8%) were reported on administration day, of which 64/70 (91.4%) resolved by the end of the next day. TEAEs commonly included headache (n = 11; 50.0%), nausea (n = 8; 36.4%), crying (n = 6; 27.3%) and fatigue (n = 6; 27.3%). There were no serious TEAEs or TEAEs leading to study withdrawal. Pre-post comparisons indicated a clinically meaningful change from Baseline in mean CAPS-5 total score at Week 4 (−29.9 (14.06)) and Week 12 (−29.5 (15.43)), which was associated with the intensity of psychedelic experience on Day 1. PCL-5 scores showed symptom reduction was rapid and sustained until Week 12. SDS total score and EQ-5D-5L index score showed similar improvements.

Conclusions: Psilocybin at a dose of 25 mg, administered with psychological support, may be safe, well-tolerated and associated with symptomatic improvement in adults with PTSD. Further investigation is warranted.

Authors: Niall M. McGowan, James J. Rucker, Rachel Yehuda, Manish Agrawal, Nadav Liam Modlin, Hollie Simmons, Agata Tofil-Kaluza, Shriya Das & Guy M. Goodwin

Summary of Investigating the safety and tolerability of single-dose psilocybin for post-traumatic stress disorder

Post-traumatic stress disorder (PTSD) is a severe psychiatric condition that arises after traumatic events and is defined by symptoms such as intrusive memories, avoidance, negative shifts in mood and cognition, and heightened arousal. It affects about 5% of the population in a given year but is more prevalent in high-risk groups, including military veterans, emergency personnel, and those from conflict zones. PTSD is associated with considerable personal suffering, diminished quality of life, and large societal costs, including healthcare use, disability, unemployment, and premature mortality.

Existing treatments include trauma-focused psychotherapies and medications like selective serotonin reuptake inhibitors (SSRIs). However, these approaches face limitations: many patients do not tolerate them, drop-out rates are high, and less than 30% achieve remission with SSRIs. Other medications are sometimes prescribed off-label but have inconsistent evidence of benefit. Complementary practices such as yoga and mindfulness may provide some relief, but effective and tolerable treatments remain scarce.

Against this backdrop, psychedelic-assisted therapies are being explored. Psilocybin, a naturally occurring psychedelic compound converted in the body to psilocin, acts on serotonin receptors and has shown rapid, durable improvements in depression in earlier Phase II studies. Its potential in PTSD has been unexplored until this trial. The researchers set out to investigate the safety and tolerability of COMP360, a pharmaceutical-grade psilocybin formulation, in adults with PTSD.

Patients and Methods

Trial Design

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Find this paper

Investigating the safety and tolerability of single-dose psilocybin for post-traumatic stress disorder: A nonrandomized open-label clinical trial

https://doi.org/10.1177/02698811251362390

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Cite this paper (APA)

McGowan, N. M., Rucker, J. J., Yehuda, R., Agrawal, M., Modlin, N. L., Simmons, H., ... & Goodwin, G. M. (2017). Investigating the safety and tolerability of single-dose psilocybin for post-traumatic stress disorder: A nonrandomized open-label clinical trial. Journal of Psychopharmacology, 02698811251362390.

Study details

Compounds studied
Psilocybin

Topics studied
PTSD Safety

Study characteristics
Original Open-Label

Participants
22 Humans

Institutes

Institutes associated with this publication

COMPASS Pathways
COMPASS Pathways is a publicly listed company (NASDAQ) that is developing psilocybin for treatment-resistant depression (TRD) for which it has completed a successful Phase IIb trial. COMPASS is one of the largest psychedelic companies and has received substantial investment from atai.

Compound Details

The psychedelics given at which dose and how many times

Psilocybin 25 mg | 1x

Linked Clinical Trial

The Safety and Tolerability of COMP360 in Participants With Post-traumatic Stress Disorder
The safety and tolerability of COMP360 in participants with post-traumatic stress disorder (PTSD).

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