The Efficacy of Doxazosin for Cocaine Users

Study Overview
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Brief Summary
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Doxazosin, an alpha 1-adrenergic receptor, may play an important role in cocaine addiction in humans. This study will evaluate the effectiveness of doxazosin in preventing drug relapse among cocaine dependent participants.

Detailed Description
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The NE system, especially the alpha 1-adrenergic receptor, may play an important role in cocaine addiction in humans. The results of this study will provide medical safety data on the duration of the induction schedule that will be optimal for attaining our target dose of 8 mg doxazosin daily and will guide future pharmacotherapy trials using Doxazosin or related alpha 1 receptor antagonists for cocaine addiction. This 17-week double-blind, placebo controlled clinical trial includes a 13 week medication trial (weeks 1-13) and up to 4 week washout period(weeks 14-17). Qualifying subjects will be randomized to receive Doxazosin 8 mg/day, or placebo during the study participation. Medication induction will occur at a rate of 2mg/week until 8mg/day target dose is achieved as follows: Dox-Fast Group: Defined as participants reaching the target dose after a 4-week titration period. Participants will be stabilized on doxazosin or placebo over weeks 4-13 (for Dox-Fast group) Dox-Slow Group: Defined as participants reaching the target dose after an 8-week titration period. Participants will be stabilized on doxazosin or placebo over weeks 8-13 (for Dox-Slow group) Both groups will be tapered off doxazosin or placebo over study weeks 14-17.

Official Title
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Doxazosin, An Alpha-1 Adrenergic Antagonist, for Cocaine Dependence: Pilot Study

Conditions
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Cocaine Dependence

Intervention / Treatment
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* Drug: Doxazosin
* Other: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Meets DSM-IV diagnosis criteria for cocaine dependence, as determined by self-reported use of cocaine at least once weekly for at least 1 month prior to study entry; a positive urine test for cocaine; and a score greater than 3 on the Severity of Dependence Scale If female, willing to use contraception throughout the study Exclusion Criteria: Meets DSM-IV diagnosis criteria for dependence on any drugs other than cocaine, or tobacco Current major psychiatric illness, including schizophrenia, bipolar disorder, or other psychotic disorder Current suicidal or homicidal ideation Current use of a prescribed psychotropic medication that cannot be discontinued History of or current major medical illness, including major heart, kidney, endocrine, or liver disorder; abnormal liver function (SGOT or SGPT levels three times greater than normal); or high blood pressure or low blood pressure High risk factor for heart disease, seizure disorders, or any illness for which disulfiram or methadone treatment would be inadvisable Currently taking metronidazole or clotrimazole Pregnant or breastfeeding

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 64 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Doxazosin<br>Medication induction occurred at a rate of 2mg/week until 8mg/day target dose was achieved as follows: Dox-Fast Group: Defined as participants reaching the target dose after a 4-week titration period. Participants were stabilized on doxazosin or placebo over weeks 4-13 (for Dox-Fast group) Dox-Slow Group: Defined as participants reaching the target dose after an 8-week titration period. Participants were stabilized on doxazosin or placebo over weeks 8-13 (for Dox-Slow group) Both groups were tapered off doxazosin or placebo over study weeks 14-17. | Drug: Doxazosin<br>* Medication induction occurred at a rate of 2mg/week until 8mg/day target dose was achieved as follows: Dox-Fast Group: Defined as participants reaching the target dose after a 4-week titration period. Participants were stabilized on doxazosin or placebo over weeks 4-13 (for Dox-Fast group) Dox-Slow Group: Defined as participants reaching the target dose after an 8-week titration period. Participants were stabilized on doxazosin or placebo over weeks 8-13 (for Dox-Slow group) Both doxazosin groups will be tapered off doxazosin or placebo over study weeks 14-17.<br>* Other names: Cardura (Doxazosin Mesylate);|
| Placebo Comparator: placebo<br>A sugar pill to mimic the experiment drug, doxazosin, will be administered in the same manner as the experimental drug through the study duration. | Other: Placebo<br>* Participants will be administered a sugar pill to mimic the doxazosin active medication with administration being the same as the active medication.<br>* Other names: sugarpills ( Capsules);|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cocaine Negative Urines | cocaine urine toxicology samples were obtained thrice weekly and tested for the presence of the cocaine metabolite, benzoylecgonine | throughout the study - up to 17 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Weeks of Abstinence | Percentage of participants achieving 2 or more consecutive weeks of abstinence | throughout the study - up to 17 weeks | 
| # of Participants That Completed the Study | Retention | throughout the study - up to 17 weeks | 
| Adverse Events |  | throughout study - upto 17 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Cocaine Dependence, Substance Related Disorders