Cocaine Use Reduction with Buprenorphine (CURB): Rationale, design, and methodology.

Effective medications to treat cocaine dependence have not been identified. Recent pharmacotherapy trials demonstrate the potential efficacy of buprenorphine (BUP) (alone or with naltrexone) for reducing cocaine use. The National Drug Abuse Treatment Clinical Trials Network (CTN) launched CTN-0048, the Cocaine Use Reduction with Buprenorphine (CURB) protocol, to examine the safety and efficacy of sublingual BUP (as Suboxone) in the presence of extended-release injectable naltrexone (XR-NTX) for the treatment of cocaine dependence. This multi-site, double-blind, placebo-controlled study will randomize 300 participants across 11 sites. Participants must meet the DSM-IV criteria for cocaine dependence and past or current opioid dependence or abuse. Participants are inducted onto XR-NTX after self-reporting at least 7 days of abstinence from opioids and tolerating a naloxone challenge followed by oral naltrexone and are then randomly assigned to one of three medication conditions (4 mg BUP, 16 mg BUP, or placebo) for 8 weeks. Participants receive a second injection of XR-NTX 4 weeks after the initial injection, and follow-up visits are scheduled at 1 and 3 months post-treatment. Participants receive weekly cognitive behavioral therapy (CBT). Recruitment commenced in September, 2011. Enrollment, active medication, and follow-up phases are ongoing, and recruitment is exceeding targeted enrollment rates. The protocol aims to demonstrate whether BUP, administered in the presence of XR-NTS, reduces cocaine use in adults with cocaine dependence and opioid use disorders and to demonstrate if XR-NTS prevents development of physiologic dependence on BUP.

Related protocols: CTN-0048