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Background and Aims Prior studies by our group demonstrated the efficacy of a brief but intensive behavioral intervention for producing initial smoking abstinence among opioid-dependent patients. In the present study, our aim was to promote longer-duration abstinence in this population. Following an initial 2-week incentive intervention for smoking abstinence, we examined whether a 10-week maintenance arm involving continuation of contingent reinforcement will produce greater smoking abstinence than a similar duration of noncontingent reinforcement. Design Randomized, 12-week, parallel-group study. Setting Out-patient research clinic in Burlington, Vermont, USA. Participants Opioid-maintained smokers (n = 88) who provided breath carbon monoxide and urinary cotinine specimens and received contingent reinforcement for smoking abstinence during weeks 1–2 (phase 1), with 63 randomized on day 14 to an extended contingent (EC; n = 31) or extended noncontingent (EN; n = 32) experimental condition for weeks 3–12 (phase 2). Intervention and control The EC condition consisted of voucher values that escalated across consecutive negative samples until they reached $30, after which they remained at $30 per negative sample. A positive or a missing sample resulted in no vouchers for that day and reset the value of the next negative same to $9. Two consecutive negatives returned the schedule to the pre-reset value. The EN control condition consisted of vouchers delivered for providing scheduled samples, but independent of smoking status. Measurements The primary outcome was percentage of biochemically abstinent samples during phase 2. Secondary measures included abstinence status at final study visit, complete abstinence, participants’ longest duration of continuous abstinence, cotinine and carbon monoxide (CO) levels and self-reported cigarettes per day. Findings EC participants achieved greater smoking abstinence during phase 2 than EN participants [46.7 versus 23.5% negative samples, respectively; odds ratio (OR) = 2.98, 95% confidence interval (CI) = 1.16–7.65, χ21 = 5.0, P = 0.02]. When longest duration of continuous abstinence was compared between experimental groups, EC participants achieved twice the mean duration of continuous abstinence compared with EN participants (3.31 versus 1.68 weeks; t61 = 1.83, P = 0.07). An effect of experimental condition was also seen on mean cotinine levels (42.5 versus 210.6 ng/ml, respectively; F1,61=5.9, P = 0.02). Conclusions Among opioid-maintained smokers receiving an initial period of daily contingent incentives, a contingent reinforcement intervention appears to be more effective at extending smoking abstinence than noncontingent reinforcement over 10 weeks.

Aims To evaluate the safety and efficacy of buprenorphine implants (BI) versus placebo implants (PI) for the treatment of opioid dependence. A secondary aim compared BI to open-label sublingual buprenorphine/naloxone tablets (BNX). Design Randomized, double-blind, placebo-controlled trial. Subjects received either four buprenorphine implants (80 mg/implant) (n = 114), four placebo implants (n = 54) or open-label BNX (12–16 mg/day) (n = 119). Setting Twenty addiction treatment centers. Participants Adult out-patients (ages 18–65) with DSM-IV-TR opioid dependence. Measurements The primary efficacy end-point was the percentage of urine samples negative for opioids collected from weeks 1 to 24, examined as a cumulative distribution function (CDF). Findings The BI CDF was significantly different from placebo (P

Aims Buprenorphine is a mu-opioid partial agonist that is marketed in a sublingual formulation as a treatment for opioid dependence. A microcapsule depot sustained-release formulation has been developed which may offer effective treatment of opioid dependence while also minimizing risks of illicit diversion or patient non-compliance. The present study examined the efficacy of depot buprenorphine in suppressing the opioid withdrawal syndrome and in attenuating the effects of exogenous opioid challenge. Design A placebo-controlled, double-blind, randomized trial. Setting A closed residential research facility. Participants A total of 15 opioid-dependent participants were enrolled into the 6-week study. Intervention Fifteen participants were randomized to receive a single subcutaneous depot injection containing buprenorphine (58 mg) or placebo. Two participants, both of whom received placebo, terminated participation after depot administration. Thirteen participants (six buprenorphine, seven placebo) completed the 6-week study and were assessed throughout the study for signs and symptoms of opioid withdrawal and for response to weekly subcutaneous challenges with 3 mg hydromorphone. Measurement Subjective, physiological and observer-rated indices of opioid withdrawal and opioid agonist effects. Findings Depot buprenorphine provided more effective relief from opioid withdrawal than placebo, as evidenced by significantly fewer buprenorphine participants requiring supplemental medications for withdrawal suppression after depot administration compared to participants receiving placebo. In the weekly hydromorphone challenge sessions, depot buprenorphine significantly reduced opioid response on measures of subjective effects and pupillary diameter. Conclusions Results from this double-blind, placebo-controlled study indicate that depot buprenorphine is effective in providing both withdrawal suppression and opioid blockade. Future studies examining additional doses and repeated dosing regimens with depot buprenorphine are warranted.