A Phase 1 interventional study of Psilocybin in Methamphetamine Use Disorder, Substance-Related Disorders and Chemically-Induced Disorders, sponsored by University of Wisconsin, Madison. Terminated at 1 site in United States. Open to participants aged 25 Years to 65 Years. Per ClinicalTrials.gov, last updated 2026-05-12.
Sponsored by University of Wisconsin, Madison · Phase 1, Interventional, and Health services research
The purpose of this research study is to investigate the safety and feasibility of two (2) oral doses of psilocybin when combined with behavioral support for methamphetamine use disorder (MUD). Participants have a diagnosis of methamphetamine use disorder (MUD). Participants can expect to be actively engaged in the study for up to 26 weeks.
The objective of this study is to determine the safety of psilocybin in adult participants with MUD.
Eligible participants will be adults with methamphetamine use disorder recruited from the community. After physical and psychological screening, and at least 6 hours of psychological support for the psilocybin dosing, each participant will ingest 1 oral dose of psilocybin. All dosing sessions will be attended by 2 specially trained facilitators, in a dedicated Session Room at the University of Wisconsin School of Pharmacy. After eight hours of observation in the dosing room, the participant will stay overnight in the hospital Clinical Research Unit, and complete an integration session with at least one of the session facilitators before discharge to home. Approximately 4 weeks after the first dose, the participant will receive a second oral dose of psilocybin, with the same length of observation.
Participants who decide not to proceed to the second dose will complete two additional integration sessions and study measures through the two-month follow-up.
If you are interested in participating in this study, please fill out a brief 1-minute survey at the link in the "More Information" section at the bottom of this record.
2,124 studies on the registry are indexed under Substance-Related Disorders; 393 are open to participants now.
This study's enrollment of 5 is below the median of 108 across 1,727 interventional studies indexed under Substance-Related Disorders.
Browse Substance-Related Disorders studies →University of Wisconsin, Madison is the lead sponsor of 1,161 studies on the registry; 182 are open to participants now.
Of its 151 completed or terminated interventional studies of FDA-regulated products, 114 (75%) have results posted.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Psilocybin with psychological support: Psilocybin will be administered in the form of capsules, taken orally with water. Each participant will receive 2 doses, approximately 4 weeks apart.
Drug: Psilocybin
25mg orally followed by 25 mg or 50 mg orally
Incidence of serious adverse events associated with oral psilocybin
Incidence of serious adverse events attributable to psilocybin as categorized according to NCI Common Toxicity Criteria version 4.0. and assigned attribution (probably, possibly, and not related).
Time frame: Up to 26 weeks
Number of participants who complete at least one dose of psilocybin
Study protocol retention and adherence for preparation, dosing and follow-up visits determined by adherence and retention rates, number of visits attended throughout the duration of the study.
Time frame: Up to 26 weeks
Number of participants who complete two-month follow-up visit
Study protocol adherence for preparation, dosing and follow-up visits determined by adherence and retention rates, number of visits attended throughout the duration of the study.
Time frame: Up to 26 weeks
Changes in substance use
Frequency of use of methamphetamine and other substances will be evaluated and tracked based on participant self-reported use at each visit.
Time frame: Up to 26 weeks
Functional changes in psychedelic and addiction-related neurocircuitry using functional magnetic resonance imaging.
Changes in functional connectivity (FC). Participants will undergo a 15-minute resting-state fMRI scanning sequence to measure changes in FC at rest pre- and post-dose.
Time frame: Up to 26 weeks
Changes in addiction-related constructs
Changes in psychological, affective, and behavioral addiction-related constructs (e.g. craving, motivation, self-efficacy, self-compassion, mindfulness, experiential avoidance, etc.) measured by brief questionnaires prior to and following each psilocybin dosing session
Time frame: Up to 26 weeks
Plan to share: No
This study is terminated, as verified in May 2026. You cannot join it, but the record below documents what was studied.
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University of Wisconsin, Madison