Opioid agonist treatment for people who are dependent on pharmaceutical opioids.

backgroundThere are ongoing concerns regarding pharmaceutical opioid-related harms, including overdose and dependence, with an associated increase in treatment demand. People dependent on pharmaceutical opioids appear to differ in important ways from people who use heroin, yet most opioid agonist treatment research has been conducted in people who use heroin. 

objectivesTo assess the effects of maintenance opioid agonist pharmacotherapy for the treatment of pharmaceutical opioid dependence. SEARCH

methodsWe updated our searches of the following databases to January 2022: the Cochrane Drugs and Alcohol Group Specialised Register, CENTRAL, MEDLINE, four other databases, and two trial registers. We checked the reference lists of included studies for further references to relevant randomised controlled trials (RCTs). SELECTION CRITERIA: We included RCTs with adults and adolescents examining maintenance opioid agonist treatments that made the following two comparisons. 1. Full opioid agonists (methadone, morphine, oxycodone, levo-alpha-acetylmethadol (LAAM), or codeine) versus different full opioid agonists or partial opioid agonists (buprenorphine) for maintenance treatment. 2. Full or partial opioid agonist maintenance versus non-opioid agonist treatments (detoxification, opioid antagonist, or psychological treatment without opioid agonist treatment). DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. MAIN

resultsWe identified eight RCTs that met inclusion criteria (709 participants). We found four studies that compared methadone and buprenorphine maintenance treatment, and four studies that compared buprenorphine maintenance to either buprenorphine taper (in addition to psychological treatment) or a non-opioid maintenance treatment comparison. We found low-certainty evidence from three studies of a difference between methadone and buprenorphine in favour of methadone on self-reported opioid use at end of treatment (risk ratio (RR) 0.49, 95% confidence interval (CI) 0.28 to 0.86; 165 participants), and low-certainty evidence from four studies finding a difference in favour of methadone for retention in treatment (RR 1.21, 95% CI 1.02 to 1.43; 379 participants). We found low-certainty evidence from three studies showing no difference between methadone and buprenorphine on substance use measured with urine drug screens at end of treatment (RR 0.81, 95% CI 0.57 to 1.17; 206 participants), and moderate-certainty evidence from one study of no difference in days of self-reported opioid use (mean difference 1.41 days, 95% CI 3.37 lower to 0.55 days higher; 129 participants). There was low-certainty evidence from three studies of no difference between methadone and buprenorphine on adverse events (RR 1.13, 95% CI 0.66 to 1.93; 206 participants). We found low-certainty evidence from four studies favouring maintenance buprenorphine treatment over non-opioid treatments in terms of fewer opioid positive urine drug tests at end of treatment (RR 0.66, 95% CI 0.52 to 0.84; 270 participants), and very low-certainty evidence from four studies finding no difference on self-reported opioid use in the past 30 days at end of treatment (RR 0.63, 95% CI 0.39 to 1.01; 276 participants). There was low-certainty evidence from three studies of no difference in the number of days of unsanctioned opioid use (standardised mean difference (SMD) -0.19, 95% CI -0.47 to 0.09; 205 participants). There was moderate-certainty evidence from four studies favouring buprenorphine maintenance over non-opioid treatments on retention in treatment (RR 3.02, 95% CI 1.73 to 5.27; 333 participants). There was moderate-certainty evidence from three studies of no difference in adverse effects between buprenorphine maintenance and non-opioid treatments (RR 0.50, 95% CI 0.07 to 3.48; 252 participants). The main weaknesses in the quality of the data was the use of open-label study designs, and difference in follow-up rates between treatment arms. AUTHORS'

conclusionsThere is  very low- to moderate-certainty evidence supporting the use of maintenance agonist pharmacotherapy for pharmaceutical opioid dependence. Methadone or buprenorphine did not differ on some outcomes, although on the outcomes of retention and self-reported substance use some results favoured methadone. Maintenance treatment with buprenorphine appears more effective than non-opioid treatments. Due to the overall very low- to moderate-certainty evidence and small sample sizes, there is the possibility that the further research may change these findings.