Improving Learning-based Treatment of Cocaine Dependence With Medication
Condition: COCAINE-RELATED DISORDERS
MeSH terms: Cocaine-Related Disorders
Study type: Interventional
Phase: Phase 2

Summary: 
      This study will test the efficacy of d-cycloserine in enhancing response to learning-based
      treatment for cocaine dependence, specifically contingency management.
    

Detailed description: 
      Cocaine dependence is a public health problem with substantial morbidity, however no
      effective pharmacotherapy for cocaine dependence has been approved by the FDA. Unlike
      previous medication studies that have sought to pharmacologically reduce cocaine
      reinforcement, seeking or craving, this exploratory clinical trial will test d-cycloserine
      (DCS) for its ability to improve learning-based behavioral treatment of cocaine dependence.
      DCS is an NMDA partial agonist that has been shown to robustly improve learning in
      preclinical models, including extinction of cocaine conditioned place preference and blockade
      of cocaine reacquisition, and to improve extinction-learning based exposure therapy for
      multiple anxiety disorders. This Phase II clinical trial will investigate the pharmacological
      (DCS) enhancement of a behavioral treatment combining contingency management (CM) and novel
      home-environment exposure therapy sessions for cocaine dependence. High magnitude CM
      incentives will be used to promote the cocaine abstinence necessary for extinction in
      home-based exposure sessions. Participants will be randomized into 2 groups: 1. CM with
      placebo (CM+PL), and 2. CM with DCS (CM+DCS). For 19 days after group assignment,
      participants will report to the laboratory 3 times per week (Mon, Wed, Fri) to provide urine
      samples, receive contingent vouchers, and complete assessments of drug use, craving, mood,
      withdrawal, and quit self-efficacy. DCS (50 mg) or placebo will be administered on Mon, Wed
      and Fri study visits (at the end of the lab visit before returning to the home environment
      for exposure sessions during the time of DCS action). Follow-up visits will be conducted at 1
      week, 1 month, and 3 months post-CM completion, during which time measures of drug use
      (self-reported and urinalysis), craving, mood, and withdrawal will be obtained. Comparison of
      continuous abstinence post-CM between the groups will be the primary outcome measure. During
      an initial laboratory session, a battery of learning/cognitive tasks will test for forms of
      learning/cognition enhanced by DCS that might contribute to the treatment effect. This
      project will test the efficacy of a novel intervention for cocaine dependence that was
      developed based on a known efficacious cocaine dependence treatment (CM), principles of
      extinction learning theory, and a medication shown to improve preclinical learning in
      general, including extinction of cocaine conditioning, and clinical learning-based exposure
      treatment of anxiety disorders. The study may indicate cost effective additions (home
      exposure sessions and DCS) to extend CM benefit after the removal of contingencies, and
      therefore may increase the dissemination of CM in community settings.
    

Intervention name(s): d-cycloserine; sugar pill
Intervention type(s): Drug; Drug
Intervention description(s): 50 mg d-cycloserine; placebo
Intervention MeSH terms: Cycloserine
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Treatment