A Phase 1 interventional study of Psilocybin in Persisting Symptoms After Concussion, sponsored by University of Calgary. Recruiting at 1 site in Canada. Open to participants aged 18 Years to 65 Years. Per ClinicalTrials.gov, last updated 2026-09-09.
Sponsored by University of Calgary · Phase 1, Interventional, and Treatment
The goal of this randomized controlled trial is to evaluate the safety, feasibility, and efficacy of psilocybin assisted therapy as an intervention to reduce symptom burden in adult patients (aged 18-65) with persisting symptoms after concussion (PSaC).
This trail will test the following 2 aims:
AIM 1 : To test the safety and feasibility of an active psilocybin-assisted psychotherapy to an active control for patients with PSaC.
AIM 2: To evaluate the efficacy of an active psilocybin-assisted psychotherapy compared to an active control as a treatment for PSaC.
Participants will be asked to:
The overall objective of this study is to evaluate the safety, feasibility, and efficacy of psilocybin assisted therapy administered with Acceptance and Commitment Therapy (ACT) as an intervention to reduce symptom burden in patients with persisting symptoms after concussion (PSaC).
This trail will test the following 2 aims:
AIM 1 : To test the safety and feasibility of an active/high dose (25mg) psilocybin-assisted psychotherapy to an active control (1mg) for adults with PSaC. Safety will be determined through the reporting of adverse events and response following psilocybin for each participant up to 6-months. Feasibility will be determined through recruitment, enrollment, and adherence rates.
AIM 2: To evaluate the efficacy of an active/high dose (25mg) psilocybin-assisted psychotherapy compared to an active control (1mg) as a treatment for PPCS at 1-week, 4 weeks, 3 months, and 6 months post-psilocybin administration. The primary efficacy outcome will be the change in PSaC burden (RPQ).
The secondary efficacy outcomes will include measures of headache, dizziness, mood, anxiety, post-traumatic stress, cognitive flexibility, emotional regulation, and quality of life.
A total of 40 male and female patients between the ages of 18-65 with a diagnosis of mild traumatic brain injury (American College of Rehabilitation Medicine 2023 criteria) who meet criteria for persisting symptoms after concussion (ICD-10) within 3 months to 5 years will be recruited from Calgary brain injury clinics and the community.
All patients will undergo a thorough, 2-part screening procedure. Eligible participants will be randomly allocated 1:1 to either the high dose (20 participants) or low dose (20 participants) psilocybin groups. All participants will be asked to attend a baseline session consisting of clinical and behavioural outcome measures, followed by a pre-dosing psychoeducation session. Following the single dosing session, participants will complete 5 weekly ACT sessions. Outcome measure assessments will be repeated at 1-week, 4 weeks, 3 months, and 6 months post-dosing.
637 studies on the registry are indexed under Brain Concussion; 163 are open to participants now.
This study's planned enrollment of 40 is below the median of 63 across 446 interventional studies indexed under Brain Concussion.
Browse Brain Concussion studies →University of Calgary is the lead sponsor of 703 studies on the registry; 196 are open to participants now.
Of its 10 completed or terminated interventional studies of FDA-regulated products, 2 (20%) have results posted.
Counted across the registry records on this site, refreshed daily.
In order to be eligible to participate in this study, an individual must meet all of the following criteria:
An individual who meets any of the following criteria will be excluded from participation in this study:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
ECG (electrocardiogram)
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
High Dose (25mg) PEX010 (Oral Psilocybin), 25mg; single dose (20 participants) administered 24hrs prior to first ACT session
Drug: Psilocybin
Low Dose (1mg) PEX010 (Oral Psilocybin), 1mg; single dose (20 participants)administered 24hrs prior to first ACT session
Drug: Psilocybin
See treatment arm description.
Also known as: magic mushrooms, PEX010
Incidence of Treatment-Emergent Adverse Events [Safety and Tolerability]
Safety will be determined based on adverse reactions and symptom reporting (categorized as mild, moderate, and severe)
Time frame: Throughout study completion, an average of 6 months
Study protocol efficacy
The primary efficacy outcome is the Rivermead Post-Concussion Symptoms Questionnaire (RPQ).The RPQ assesses the severity of 16 commonly experienced PSaC symptoms using a scale of 0 ("not experienced") to 4 ("severe problem"), with higher scores indicating greater PSaC symptom burden.
Time frame: Throughout study completion, an average of 6 months
Study protocol feasibility
The feasibility will be determined based on recruitment (greater than 30% of those screened eligible), attendance (70% intervention appointment attendance), retention (70% complete study protocol)
Time frame: Screening, enrolment, intervention, and participation up to study end point (6-months)
Montgomery-Asberg Depression Rating Scale Self report (MADRS-S)
The MADRS is a 10-item assessment of depressive symptoms using a recall period of the past 7 days. Total scores range from 0-60, with higher scores indicating greater depression.
Time frame: Throughout study completion, an average of 6 months [assessed at baseline, and 1-week, 4 weeks, 3 months, and 6 months post-dosing]
Generalized Anxiety Disorder-7 (GAD-7).
The GAD-7 is a 7-item tool which assess anxiety. Individuals rate how often they have been bothered by seven listed problems and score their responses from 0 ("not at all") to 3 ("nearly every day"). Total scores for anxiety severity are: 0-4: minimal anxiety; 5-9: mild; 10-14: moderate; 15-21: severe anxiety.
Time frame: Throughout study completion, an average of 6 months [assessed at baseline, and 1-week, 4 weeks, 3 months, and 6 months post-dosing]
Sleep and Concussion Questionnaire (SCQ)
During the SCQ-initial, participants use the timeframe of the 6-months prior to the concussion, and since the concussion. The SCQ-follow-up will have a recall period of since the most recent SCQ was completed. Total scores of 0-7 indicate no clinically significant change; 8-15: subclinical change; 16-22: clinical changes of moderate severity; 23-36: clinically severe changes in sleep or wakefulness.
Time frame: Throughout study completion, an average of 6 months [assessed at baseline, and 1-week, 4 weeks, 3 months, and 6 months post-dosing]
Headache Impact Test (HIT-6).
This 6-item tool assesses how headache intensity impacts daily life functioning. Headache intensity and frequency are measured from "never" to "always", with greater scores indicating greater impact on daily life function due to headache. Total scores of 49 or less indicate headaches have little to no impact on daily life; 50-55: headaches have some impact on life; 56-59: headaches have substantial impact on life; 60 or more: headaches have severe impact on life.
Time frame: Throughout study completion, an average of 6 months [assessed at baseline, and 1-week, 4 weeks, 3 months, and 6 months post-dosing]
Dizziness Handicap Questionnaire (DHI)
A 25-item self-reported questionnaire which assesses the impact of dizziness on daily life. Scores from functional, emotional, and physical domains are summed to give a score between 0-100 with greater scores indicating greater impact.
Time frame: Throughout study completion, an average of 6 months [assessed at baseline, and 1-week, 4 weeks, 3 months, and 6 months post-dosing]
PTSD Checklist for DSM-5 (PCL-5)
A 20-item self-report measure that assesses the 20 DSM-5 symptoms of PTSD. Greater symptom scores indicate greater symptom burden
Time frame: Throughout study completion, an average of 6 months [assessed at baseline, and 1-week, 4 weeks, 3 months, and 6 months post-dosing]
The Quality of Life after Brain Injury (QOLIBRI)
This questionnaire measures health-related quality of life specific to individuals after traumatic brain injury. Covers six domains of health-related quality of life (cognition, self, daily life and autonomy, social relationships, emotions, and physical problems) to provide an overall score, with higher scores indicating greater quality of life.
Time frame: Throughout study completion, an average of 6 months [assessed at baseline, and 1-week, 4 weeks, 3 months, and 6 months post-dosing]
Difficulties in Emotion Regulation Scale (DERS)
A 36-item self-report scale designed to assess multiple aspects of emotion dysregulation. Six subscale scores and a total score are calculated.
Time frame: Throughout study completion, an average of 6 months [assessed at baseline, and 1-week, 4 weeks, 3 months, and 6 months post-dosing]
Think Aloud Task
The Thinking Aloud Task (TAT) measures cognitive flexibility in relation to thought dynamics, tapping into the speed and expansiveness of thoughts, which relate to real-time emotion regulation and overall social and emotional well-being.
Time frame: Throughout study completion, an average of 6 months [assessed at baseline, and 1-week, 4 weeks, and 3 months post-dosing]
Probabilistic Reversal Learning Task
The Probabilistic Reversal Learning (PRL) task is a measure of reward-related cognitive flexibility that requires participants to choose a shape that fits an inferred rule and adapt behavior once rules switch
Time frame: Throughout study completion, an average of 6 months [assessed at baseline, and 1-week, 4 weeks, and 3 months post-dosing]
The Acceptance and Action Questionnaire II (AAQ-II)
A 7-item questionnaire measuring psychological flexibility. Scores range from 0 to 49 with higher scores indicating greater psychological flexibility
Time frame: Throughout study completion, an average of 6 months [assessed at baseline, and 1-week, 4 weeks, 3 months, and 6 months post-dosing]
The Acceptance and Action after Brain Injury Questionnaire (AAQ-ABI)
A 7-item questionnaire which measures psychological flexibility about the thoughts and feelings related to brain injury. Scored on a 5-point Likert scale, scores range from 0-36 with higher scores indicating greater psychological flexibility
Time frame: Throughout study completion, an average of 6 months [assessed at baseline, and 1-week, 4 weeks, 3 months, and 6 months post-dosing]
Cognitive Fusion Questionnaire (CFQ-7)
A 7-point Likert scale measuring cognitive fusion. Scores range from 0 to 49 with higher scores indicating greater fusion with one's thoughts.
Time frame: Throughout study completion, an average of 6 months [assessed at baseline, and 1-week, 4 weeks, 3 months, and 6 months post-dosing]
Bergs Card Sorting Task
Cognitive flexibility task - Participants must select the stimulus that is different from others based on feedback and adapt their responses once the criteria for correct choice switches. Perseverative errors are defined as the number of instances in which three incorrect responses are made based on a previous rule, and they are thought to reflect less cognitive flexibility (or cognitive rigidity)
Time frame: Throughout study completion, an average of 6 months [assessed at baseline, and 1-week, 4 weeks, and 3 months post-dosing]
Plan to share: No
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Studies of the drug tested here: Psilocybin