Effects of Psilocybin on Speech Fluency, Struggle, and Brain Activity in People Who Stutter (NCT07296328) | Clinical Trial Compass
Not Yet RecruitingPhase 2
Effects of Psilocybin on Speech Fluency, Struggle, and Brain Activity in People Who Stutter
United States25 participantsStarted 2026-01-15
Plain-language summary
This Phase 2a clinical trial is an open-label, single-group, within-subjects pilot study designed to evaluate the safety, feasibility, and preliminary efficacy of psilocybin as a therapeutic intervention for adults with developmental stuttering. This pilot study will assess whether further research to explore the potential benefits of psilocybin-assisted therapy for improving clinical outcomes in individuals who stutter, is warranted. The aims of this study include:
* Aim 1: Assess the safety and feasibility of psilocybin as a therapeutic agent for stuttering.
* Aim 2: Evaluate the effects of psilocybin on objective and subjective measures of stuttering severity, struggle, and well-being.
* Aim 3: Explore the therapeutic neural mechanisms of psilocybin in stuttering.
Who can participate
Age range
18 Years – 50 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion criteria
. Do not have a uterus;
. Are postmenopausal (has had 12 months of natural amenorrhea with a matching clinical profile \[age, history of vasomotor symptoms\]) prior to Screening Part 2; or
. Are surgically sterile (documented hysterectomy, bilateral salpingectomy, or bilateral oophorectomy).
. Have a negative pregnancy test at Screening (Reassessed at Day 0 (pre-IP administration);
. Not be currently breastfeeding;
. Not intend to become pregnant during participation in this study;
. Agree to use a highly effective form of contraception from the time of Screening until 7 days after the IP Administration Session. Highly effective forms of contraception include:
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
Change in Stuttering Severity Instrument - 4th Edition (SSI-4) total score
Timeframe: Week 4, Week 12
2
Change in frequency subcomponent score of the SSI-4
Timeframe: Week 4, Week 12
3
Change in duration subcomponent score of the SSI-4
Timeframe: Week 4, Week 12
4
Change in physical concomitants subcomponent score of the SSI-4
Timeframe: Week 4, Week 12
5
Change in Overall Assessment of the Speaker's Experience of Stuttering - Adults (OASES-A) score