Evaluation of buspirone for relapse-prevention in adults with cocaine dependence: an efficacy trial conducted in the real world.

Cocaine dependence is a significant public health problem for which there are currently no FDA-approved medications. Hence, identifying candidate compounds and employing an efficient evaluation process is crucial. This paper describes key design decisions made for a National Institute on Drug Abuse (NIDA) Clinical Trials Network (CTN) study that uses a novel two-stage process to evaluate buspirone (60 mg/day) for cocaine-relapse prevention. The study includes pilot (N=60) and full-scale (estimated N=264) trials. Both trials will be randomized, double-blind, and placebo-controlled and both will enroll treatment-seeking cocaine-dependent participants engaged in inpatient/residential treatment and scheduled for outpatient treatment post-discharge. All participants will receive contingency management in which incentives are given for medication adherence as evaluated by the Medication Events Monitoring System (MEMS). The primary outcome measure is maximum days of continuous cocaine abstinence, as assessed by twice-weekly urine drug screens (UDS) and self-report, during the 15-week outpatient treatment phase. Drug-abuse outcomes include cocaine use as assessed by UDS and self-report of cocaine use, other substance use as assessed by UDS and self-report of substance use (i.e., alcohol and/or illicit drugs), cocaine bingeing, HIV risk behavior, quality of life, functioning, and substance abuse treatment attendance. Unique aspects of the study include conducting an efficacy trial in community treatment programs, a two-stage process to efficiently evaluate buspirone, and an evaluation of mediators by which buspirone might exert a beneficial effect on relapse prevention.