Cocaine-Related Disorders | Psilocybin-facilitated Treatment for Cocaine Use

Cocaine-Related Disorders research study

What is the primary objective of this study?

The primary purpose of this study is to evaluate the feasibility and estimate the efficacy of psilocybin-facilitated treatment for cocaine use. We also will monitor the impact of psilocybin-facilitated treatment on the use of other drugs and outcomes relevant to cocaine involvement (e.g., criminal involvement). MRI assessment is a unique aspect of this study. As a potential biological mechanism of psilocybin's effect includes changes in default mode network functional connectivity (Carhart-Harris et al., 2012), we will determine if psilocybin's therapeutic effects are mediated by such changes. Moreover, as Glx (a brain metabolite that reflects glutamate) abnormalities have been shown to play a role in cocaine addiction, we will determine if psilocybin impacts Glx in the anterior cingulate cortex and hippocampus.

Who is eligible to participate?

Inclusion Criteria: - 25 years of age and older - Score of at least 3 on the Severity of Dependence Scale - Desire to cease cocaine use as indicated by a goal of complete cocaine abstinence on the Thoughts about Abstinence questionnaire - Ability to read/write in English - No prior hallucinogen use or it will have been at least 3 years since their last use of a hallucinogen - Availability of 3 community observers to complete community observer forms via telephone around baseline and follow-up assessments. - Availability of a friend or family member into whose care the participant can be released following their drug administration session. - In good general health as assessed by detailed medical history and physical examination - Abstinence from cocaine for at least 7 days prior to experimental drug administration as confirmed via urinalysis and no signs of intoxication on other drugs. Exclusion Criteria: - 24 years of age and younger - Women who are pregnant or breast feeding - Current psychiatric diagnoses other than substance abuse/dependence - Current hypertension (exceeding 140 systolic and 90 diastolic at resting as described below) - Use of tricyclic antidepressants, lithium, Selective Serotonin Reuptake Inhibitors, Monoamine Oxidase Inhibitors, haloperidol, St. John's Wort, or other antipsychotic medications, mood stabilizers, or medications with serotonin activity - History of any psychotic disorders - History of bipolar I or II disorder - First or second-degree relatives with any psychotic disorders, or bipolar I or II disorders - Current suicidal or homicidal ideation - Planning to move from the Birmingham area in the next 6 months - Contraindications of MRI (metallic objects in the body, claustrophobia, difficulty with prior MRI)

Which medical condition, disease, disorder, syndrome, illness, or injury is researched?

Cocaine-Related Disorders

Study Interventions

Interventions can include giving participants drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available or noninvasive approaches such as surveys, education, and interviews.

Drug:Psilocybinthis has been used in treating obsessive-compulsive disorders, cluster headaches, anxiety, and drug dependence.

Drug:DiphenhydramineThis drug will be used as the control. Diphenhydramine is a histamine blocker.

Study Arms

Research studies and clinical trials typically have two or more research arms. An arm is a group of people who receive the same treatment in the study.

Psilocybin administrationPsilocybin will be administered in pill form at a dose of .36 mg/kg. Psilocybin will be administered in one session over the course of 8 hours.

Diphenhydramine administrationDiphenhydramine will be administered in pill form at a dose of 100 mg. Diphenhydramine will be administered in one session over the course of 8 hours.

Study Status


Start Date: May 2015

Completed Date: August 2020

Phase: Phase 2

Type: Interventional


Primary Outcome: The difference between the treatment and placebo groups in the number of participants with biochemically verified cocaine abstinence.

Secondary Outcome:

Study sponsors, principal investigator, and references

Principal Investigator: Peter S. Hendricks, Ph.D.

Lead Sponsor: University of Alabama at Birmingham


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