The proposed study is designed to develop a more effective treatment program for heroin-dependent poly-drug abusers. We will determine whether Voucher-Based Reinforcement Therapy (VBRT) enhances outcome when combined with a pharmacotherapy/psychosocial treatment program. Previous studies demonstrated that both the pharmacotherapy (buprenorphine) and VBRT are moderately effective for decreasing heroin abuse when used independently. VBRT involves contingent reinforcement for drug-free urines; it is designed to reinforce continuous abstinence and the development of a drug-free lifestyle. Previous studies have used VBRT to target a specific drug; however, the approach can be easily extended to target use of several illicit drugs concurrently, as is proposed in this study. In contrast, buprenorphine alone is often not effective in helping patients achieve abstinence from the other drugs often abused by heroin dependent individuals since buprenorphine's effects are pharmacologically specific.
The aim of this proposal is to determine whether VBRT can enhance a standard buprenorphine program's effectiveness in achieving abstinence from several drugs.
Other specific aims i nclude evaluation of (a) the relative efficacy of a reduced-value VBRT program; (b) a less costly urine testing regimen; and (c) the role of gender, race, and psychiatric comorbidity, including Antisocial Personality Disorder, in treatment outcome. Heroin dependent poly-drug abusers will receive buprenorphine in the context of our standard psychosocial clinic program (29 Weeks). They will be inducted onto buprenorphine during Weeks 1-2 and maintained on a fixed dose for Weeks 3 through 25. At Week 6. all participants who continue to show evidence of illicit drug use will be randomly assigned to one of three treatment groups for a twelve week VBRT phase (Weeks 6-17). The three treatment groups are standard VBRT, a VBRT condition in which voucher values are reduced, and a yoked control condition. Yoked control participants are linked to an active VBRT participant and receive vouchers of the same value and frequency as that individual, but independent of their urinalysis results. After the VBRT intervention phase, participants will be maintained on buprenorphine with weekly individual counseling and medical monitoring for 8 more weeks (Weeks 18-25), followed by a 4-week phase of gradual withdrawal from buprenorphine (Weeks 26-29). All participants will be asked to return to the clinic for a 12-month follow-up visit.
