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Carbidopa/Levodopa Combined With Behavioral Therapy for the Treatment of Cocaine Dependence

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ClinicalTrials.gov Identifier: NCT00713583
Recruitment Status : Completed
First Posted : July 11, 2008
Results First Posted : March 19, 2018
Last Update Posted : April 23, 2018
Sponsor:
Collaborator:
National Institute on Drug Abuse (NIDA)
Information provided by (Responsible Party):
Joy Schmitz, The University of Texas Health Science Center, Houston

Brief Summary:
Cocaine dependence is a major public health problem and the development of a treatment for this disorder is a priority. To date, treatment interventions based on positive incentive principles have shown the strongest effects for improving substance use outcomes. One such example is contingency management (CM) interventions in which nondrug rewards are used to compete with cocaine. Recent evidence suggests that certain medications improve response to CM interventions, particularly agents that target dopamine reward systems in the brain. A promising dopamine-enhancing medication is levodopa. The study team has observed the strongest effects of levodopa when the medication is administered in the context of CM therapy, perhaps through mechanisms that enhance reward saliency. The proposed study is designed to further evaluate this promising treatment approach. Cocaine dependent outpatients will participate in a randomized, 2-group (levodopa vs. placebo), double-blind clinical trial. CM will be behavioral therapy platform for both treatment groups. The study will test the primary hypothesis that CM+levodopa will be more effective than CM+placebo in reducing cocaine use. This study is expected to validate the usefulness of a new behavioral-pharmacological treatment approach for cocaine dependence.

Condition or disease Intervention/treatment Phase
Cocaine Dependence Drug: levodopa Drug: Placebo Behavioral: Cognitive Behavioral Therapy Behavioral: Contingency Management Phase 2

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 85 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Contingency Management Plus Levodopa/Carbidopa for Treatment of Cocaine Dependence
Study Start Date : January 2008
Actual Primary Completion Date : December 2011
Actual Study Completion Date : December 2011

Resource links provided by the National Library of Medicine

U.S. FDA Resources

Arm Intervention/treatment
Experimental: Levodopa pharmacotherapy
Levodopa pharmacotherapy (800mg levodopa and 200mg carbidopa per day), cognitive behavioral therapy (CBT), and contingency management (CM).
Drug: levodopa
800mg levodopa and 200mg carbidopa per day
Other Name: Sinemet
Behavioral: Cognitive Behavioral Therapy
Participants received individual cognitive behavioral therapy (CBT) in 50-minute weekly sessions. These sessions were manual-driven and based on the relapse prevention model proposed by Marlatt and Gordon (1985). Trained masters-level therapists, under the supervision of senior therapists and the principal investigator, worked with participants to teach them how to recognize and cope with risky situations that could influence their cocaine use through self-monitoring of situational craving and drug use stimuli, coping skills training, and lifestyle modifications.
Behavioral: Contingency Management
An abstinence-based contingency management (CM) procedure was used. Participants earned vouchers according to the reward schedule recommended by Budney and Higgins (1998), beginning at $2.50 for the first cocaine-negative urine. For each consecutive cocaine-negative urine, voucher values increased by $1.25 with a $10 bonus given for provision of three consecutive cocaine-negative urines within a week. A cocaine-positive urine or failure to provide a scheduled urine sample resulted in a reset of the schedule to the initial value of $2.50. After provision of five negative urines, the voucher returned to the value prior to the reset. Participants were able to redeem their vouchers for small amounts of cash (≤$25) or gift cards for goods and services.
Placebo Comparator: Placebo
Placebo, cognitive behavioral therapy (CBT), and contingency management (CM).
Drug: Placebo
Placebo
Behavioral: Cognitive Behavioral Therapy
Participants received individual cognitive behavioral therapy (CBT) in 50-minute weekly sessions. These sessions were manual-driven and based on the relapse prevention model proposed by Marlatt and Gordon (1985). Trained masters-level therapists, under the supervision of senior therapists and the principal investigator, worked with participants to teach them how to recognize and cope with risky situations that could influence their cocaine use through self-monitoring of situational craving and drug use stimuli, coping skills training, and lifestyle modifications.
Behavioral: Contingency Management
An abstinence-based contingency management (CM) procedure was used. Participants earned vouchers according to the reward schedule recommended by Budney and Higgins (1998), beginning at $2.50 for the first cocaine-negative urine. For each consecutive cocaine-negative urine, voucher values increased by $1.25 with a $10 bonus given for provision of three consecutive cocaine-negative urines within a week. A cocaine-positive urine or failure to provide a scheduled urine sample resulted in a reset of the schedule to the initial value of $2.50. After provision of five negative urines, the voucher returned to the value prior to the reset. Participants were able to redeem their vouchers for small amounts of cash (≤$25) or gift cards for goods and services.



Primary Outcome Measures :
  1. Confirmed Abstinence From Cocaine as Assessed by Treatment Effectiveness Score (TES) [ Time Frame: 12 weeks of treatment ]
    The Treatment Effectiveness Score (TES) is the number of cocaine-negative urines collected out of the total scheduled urine tests for the 12-week trial (36 total scheduled urine tests per participant). The mean number of cocaine-negative urines over all time points is reported in this outcome measure.



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Ages Eligible for Study:   18 Years to 60 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • between 18 and 60 years of age
  • meet Diagnostic and Statistical Manual of Mental Disorders, 4th. Edition (DSM-IV) criteria for current cocaine dependence.
  • be in acceptable health on the basis of interview, medical history and physical exam.

Exclusion Criteria:

  • current DSM-IV diagnosis of any psychoactive substance dependence other than cocaine, marijuana, or nicotine.
  • have a DSM-IV axis I psychiatric disorder or neurological disease or disorder requiring ongoing treatment and/or making study participation unsafe.
  • have significant current suicidal or homicidal ideation.
  • have medical conditions contraindicating levodopa/carbidopa pharmacotherapy. Conditions include severe pulmonary disease (bronchial asthma, emphysema), cardiovascular disease (severe or history of myocardial infarction with residual arrhythmias), narrow angle glaucoma, melanoma, history of peptic ulcer, renal function impairment.
  • taking medications known to have significant drug interactions with levodopa/carbidopa (e.g., monoamine oxidase (MAO) inhibitors, anticonvulsants, haloperidol, phenothiazines, selegiline, anesthetics).
  • currently or recently (last 3 months) treated for substance use or another psychiatric condition.
  • having conditions of probation or parole requiring reports of drug use to officers of the court.
  • impending incarceration.
  • pregnant or nursing for female patients.
  • inability to read, write, or speak English.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00713583


Locations
United States, Texas
The University of Texas Health Science Center at Houston
Houston, Texas, United States, 77030
Sponsors and Collaborators
The University of Texas Health Science Center, Houston
National Institute on Drug Abuse (NIDA)
Investigators
Principal Investigator: Joy M Schmitz, PhD University of Texas at Houston

Responsible Party: Joy Schmitz, Professor - Psychiatry, Behavioral Sciences, The University of Texas Health Science Center, Houston
ClinicalTrials.gov Identifier: NCT00713583     History of Changes
Other Study ID Numbers: 1R01DA023608-01 ( U.S. NIH Grant/Contract )
1R01DA023608-01 ( U.S. NIH Grant/Contract )
R01DA023608-01 ( U.S. NIH Grant/Contract )
DPMCDA ( Other Identifier: NIDA )
First Posted: July 11, 2008    Key Record Dates
Results First Posted: March 19, 2018
Last Update Posted: April 23, 2018
Last Verified: March 2018

Studies a U.S. FDA-regulated Drug Product: Yes
Studies a U.S. FDA-regulated Device Product: No
Product Manufactured in and Exported from the U.S.: No

Keywords provided by Joy Schmitz, The University of Texas Health Science Center, Houston:
Cocaine, levodopa, contingency management

Additional relevant MeSH terms:
Cocaine-Related Disorders
Substance-Related Disorders
Chemically-Induced Disorders
Mental Disorders
Cocaine
Levodopa
Carbidopa
Anesthetics, Local
Anesthetics
Central Nervous System Depressants
Physiological Effects of Drugs
Sensory System Agents
Peripheral Nervous System Agents
Vasoconstrictor Agents
Dopamine Uptake Inhibitors
Neurotransmitter Uptake Inhibitors
Membrane Transport Modulators
Molecular Mechanisms of Pharmacological Action
Dopamine Agents
Neurotransmitter Agents
Antiparkinson Agents
Anti-Dyskinesia Agents
Aromatic Amino Acid Decarboxylase Inhibitors
Enzyme Inhibitors