Controlled, randomized trial in maintenance treatment of intravenous buprenorphine dependence with naltrexone, methadone or buprenorphine: a novel study

Buprenorphine versus methadone for the treatment of opioid dependence: a systematic review and meta-analysis of randomised and observational studies

BACKGROUND

Opioid dependence is associated with substantial health and social burdens, and opioid agonist treatment (OAT) is highly effective in improving multiple outcomes for people who receive this treatment. Methadone and buprenorphine are common medications provided as OAT. We aimed to examine buprenorphine compared with methadone in the treatment of opioid dependence across a wide range of primary and secondary outcomes.

METHODS

We did a systematic review and meta-analysis in accordance with GATHER and PRISMA guidelines. We searched Embase, MEDLINE, CENTRAL, and PsycINFO from database inception to Aug 1, 2022; clinical trial registries and previous relevant Cochrane reviews were also reviewed. We included all RCTs and observational studies of adults (aged ≥18 years) with opioid dependence comparing treatment with buprenorphine or methadone. Primary outcomes were retention in treatment at 1, 3, 6, 12, and 24 months, treatment adherence (measured through doses taken as prescribed, dosing visits attended, and biological measures), or extra-medical opioid use (measured by urinalysis and self-report). Secondary outcomes were use of benzodiazepines, cannabis, cocaine, amphetamines, and alcohol; withdrawal; craving; criminal activity and engagement with the criminal justice system; overdose; mental and physical health; sleep; pain; global functioning; suicidality and self-harm; and adverse events. Single-arm cohort studies and RCTs that collected data on buprenorphine retention alone were also reviewed. Data on study, participant, and treatment characteristics were extracted. Study authors were contacted to obtain additional data when required. Comparative estimates were pooled with use of random-effects meta-analyses. The proportion of individuals retained in treatment across multiple timepoints was pooled for each drug. This study is registered with PROSPERO (CRD42020205109).

FINDINGS

We identified 32 eligible RCTs (N=5808 participants) and 69 observational studies (N=323 340) comparing buprenorphine and methadone, in addition to 51 RCTs (N=11 644) and 124 observational studies (N=700 035) that reported on treatment retention with buprenorphine. Overall, 61 studies were done in western Europe, 162 in North America, 14 in north Africa and the Middle East, 20 in Australasia, five in southeast Asia, seven in south Asia, two in eastern Europe, three in central Europe, one in east Asia, and one in central Asia. 1 040 827 participants were included in these primary studies; however, gender was only reported for 572 111 participants, of whom 377 991 (66·1%) were male and 194 120 (33·9%) were female. Mean age was 37·1 years (SD 6·0). At timepoints beyond 1 month, retention was better for methadone than for buprenorphine: for example, at 6 months, the pooled effect favoured methadone in RCTs (risk ratio 0·76 [95% CI 0·67-0·85]; I·=74·2%; 16 studies, N=3151) and in observational studies (0·77 [0·68-0·86]; I·=98·5%; 21 studies, N=155 111). Retention was generally higher in RCTs than observational studies. There was no evidence suggesting that adherence to treatment differed with buprenorphine compared with methadone. There was some evidence that extra-medical opioid use was lower in those receiving buprenorphine in RCTs that measured this outcome by urinalysis and reported proportion of positive urine samples (over various time frames; standardised mean difference -0·20 [-0·29 to -0·11]; I·=0·0%; three studies, N=841), but no differences were found when using other measures. Some statistically significant differences were found between buprenorphine and methadone among secondary outcomes. There was evidence of reduced cocaine use, cravings, anxiety, and cardiac dysfunction, as well as increased treatment satisfaction among people receiving buprenorphine compared with methadone; and evidence of reduced hospitalisation and alcohol use in people receiving methadone. These differences in secondary outcomes were based on small numbers of studies (maximum five), and were often not consistent across study types or different measures of the same constructs (eg, cocaine use).

INTERPRETATION

Evidence from trials and observational studies suggest that treatment retention is better for methadone than for sublingual buprenorphine. Comparative evidence on other outcomes examined showed few statistically significant differences and was generally based on small numbers of studies. These findings highlight the imperative for interventions to improve retention, consideration of client-centred factors (such as client preference) when selecting between methadone and buprenorphine, and harmonisation of data collection and reporting to strengthen future syntheses.

FUNDING

Australian National Health and Medical Research Council.

Opioid agonist treatment for people who are dependent on pharmaceutical opioids

BACKGROUND

There 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.  OBJECTIVES: To assess the effects of maintenance opioid agonist pharmacotherapy for the treatment of pharmaceutical opioid dependence.

SEARCH METHODS

We 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 RESULTS

We 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' CONCLUSIONS

There 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.

Relative effectiveness of medications for opioid-related disorders: A systematic review and network meta-analysis of randomized controlled trials

INTRODUCTION

Several pharmacotherapeutic interventions are available for maintenance treatment for opioid-related disorders. However, previous meta-analyses have been limited to pairwise comparisons of these interventions, and their efficacy relative to all others remains unclear. Our objective was to unify findings from different healthcare practices and generate evidence to strengthen clinical treatment protocols for the most widely prescribed medications for opioid-use disorders.

METHODS

We searched Medline, EMBASE, PsycINFO, CENTRAL, and ClinicalTrials.gov for all relevant randomized controlled trials (RCT) from database inception to February 12, 2022. Primary outcome was treatment retention, and secondary outcome was opioid use measured by urinalysis. We calculated risk ratios (RR) and 95% credible interval (CrI) using Bayesian network meta-analysis (NMA) for available evidence. We assessed the credibility of the NMA using the Confidence in Network Meta-Analysis tool.

RESULTS

Seventy-nine RCTs met the inclusion criteria. Due to heterogeneity in measuring opioid use and reporting format between studies, we conducted NMA only for treatment retention. Methadone was the highest ranked intervention (Surface Under the Cumulative Ranking [SUCRA] = 0.901) in the network with control being the lowest (SUCRA = 0.000). Methadone was superior to buprenorphine for treatment retention (RR = 1.22; 95% CrI = 1.06-1.40) and buprenorphine superior to naltrexone (RR = 1.39; 95% CrI = 1.10-1.80). However, due to a limited number of high-quality trials, confidence in the network estimates of other treatment pairs involving naltrexone and slow-release oral morphine (SROM) remains low.

CONCLUSION

All treatments had higher retention than the non-pharmacotherapeutic control group. However, additional high-quality RCTs are needed to estimate more accurately the extent of efficacy of naltrexone and SROM relative to other medications. For pharmacotherapies with established efficacy profiles, assessment of their long-term comparative effectiveness may be warranted.

TRIAL REGISTRATION

This systematic review has been registered with PROSPERO (https://www.crd.york.ac.uk/prospero) (identifier CRD42021256212).

Retention in opioid agonist treatment: a rapid review and meta-analysis comparing observational studies and randomized controlled trials

BACKGROUND

Although oral opioid agonist therapies (OATs), buprenorphine and methadone, are effective first-line treatments, OAT remains largely underutilized due to low retention rates and wide variation across programs. This rapid review therefore sought to summarize the retention rates reported by randomized controlled trials (RCTs) and controlled observational study designs that compared methadone to buprenorphine (or buprenorphine-naloxone).

METHODS

We searched four electronic databases (EMBASE, MEDLINE, Cochrane Central Register of Controlled Trials, CINAHL, up to April 2018) for RCTs and controlled observational studies that compared oral fixed-dose methadone to buprenorphine versus methadone (or buprenorphine-naloxone). Data were extracted separately for two different definitions of retention in treatment: (1) length of time retained in the study and (2) presence on the final day of a study. Separate random effects meta-analyses were performed for RCTs and controlled observational studies. Data from controlled observational studies where retention was measured as the length of time retained in the study were not amenable to meta-analysis.

RESULTS

Among 7603 studies reviewed, 10 RCTs and 3 observational studies met inclusion criteria (n = 5065) and compared fixed-dose oral buprenorphine with methadone. Across studies, the average retention rate was highly variable (RCTs: buprenorphine 20.0-82.5% and methadone 30.7-83.8%; observational studies: buprenorphine 20.2-78.3% and methadone 48.3-74.8%). For time period retained in the study, we observed no significant difference in treatment retention for buprenorphine versus methadone in RCTs (standardized mean difference [SMD] =  - 0.07; 95% CI - 0.35-0.21, p = 0.63; quality of evidence: low). For presence on the final study day, we observed no significant difference between buprenorphine and methadone treatment retention in RCTs (risk ratio [RR] = 0.89; 95% CI 0.73-1.08, p = 0.24; quality of evidence: low) and controlled observational studies (RR = 0.75; 95% CI 0.36-1.58, p = 0.45).

CONCLUSION

Meta-analysis of existing RCTs suggests retention in oral fixed-dose opioid agonist therapy with methadone appears to be generally equal to buprenorphine (or buprenorphine-naloxone), with wide variation across studies. Similarly, a meta-analysis of three controlled observational studies indicated no difference in treatment retention although there was significant heterogeneity among the included studies. The length of follow-up did not appear to affect the retention rate.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42018104452 .

The Opioid Epidemic: Impact on Inflammation and Cardiovascular Disease Risk in HIV

PURPOSE OF REVIEW

People infected with HIV through injection drug use are more likely to experience progression to AIDS, death due to AIDS, and all-cause mortality even when controlling for access to care and antiretroviral therapy. While high-risk behavior and concurrent infections most certainly are contributors, chronic immune activation, downstream metabolic comorbidities may play an important role.

RECENT FINDINGS

Altered intestinal integrity plays a major role in HIV-related immune activation and microbial translocation markers are heightened in active heroin users. Additionally, greater injection frequency drives systemic inflammation and is associated with HIV viral rebound. Finally, important systemic inflammation markers have been linked with frailty and mortality in people who inject drugs with and without concurrent HIV infection. Heroin use may work synergistically with HIV infection to cause greater immune activation than either factor alone. Further research is needed to understand the impact on downstream metabolic comorbidities including cardiovascular disease. Medication-assisted treatment for opioid use disorder with methadone or buprenorphine may ameliorate some of this risk; however, there is presently limited research in humans, including in non-HIV populations, describing changes in immune activation on these treatments which is of paramount importance for those with HIV infection.

Rapid effect of a single-dose buprenorphine on reduction of opioid craving and suicidal ideation: A randomized, double blind, placebo-controlled study

Objective

Opioid use disorder is a prevalent addiction problem that can be treated with buprenorphine, but dependence, diversion, and abuse of buprenorphine occur. Although including naloxone reduces these problems, the combination formulation is not available worldwide. The administration of the medication under supervision may also be useful in decreasing unintended uses of the medication. The objective is to assess the influence of a single, physician-administered dose of buprenorphine on withdrawal craving and suicidal ideation in opioid-dependent patients over a period of 4 days of abstinence from opioids.

Materials and Methods

Sixty-one men who used heroin, opium, or prescription opioids and met Diagnostic and Statistical Manual of Mental Disorders Five Edition criteria for opioid use disorder were randomized to receive a single, sublingual dose of buprenorphine (16 mg, 32 mg, or placebo; n's = 20, 20, and 21 per group). The study was carried out in an inpatient psychiatric ward, with appropriate precautions and monitoring of cardiovascular and respiratory measures. Buprenorphine was administered when the patients were in moderate opioid withdrawal, exhibiting four to five symptoms. Self-reports of craving (The Opioid Craving Scale) and suicidal ideation (Beck Scale for Suicidal Ideation) were taken at baseline and on each of the 4 days after treatment.

Results

The group did not differ significantly on demographic features, and all of the patients completed the 4-day study. Craving was reduced from baseline during the observation period in each of the three groups, demonstrating a significant effect of treatment (P < 0.0005), and the dose-by-time interaction (P < 0.0005). Both 32 mg and 16 mg groups differed significantly from the placebo group. No significant differences were observed between the 32 and 16 mg groups, suggesting that the maximal effect on craving reduction was achieved with the 16-mg dose. Suicidal ideation was decreased from baseline during the observation period in each of the three groups, demonstrating a significant effect of treatment (P < 0.0005), and the dose-by-time interaction (P < 0.017).The 32 mg group differed significantly from the placebo group. No significant differences were observed between the 16 and placebo groups, suggesting that the maximal effect on suicidal ideation reduction was achieved with the 32 mg dose.

Conclusions

A single high dose of 16 mg or 32 mg buprenorphine reduces opioid craving, but a single high dose of only 32 mg buprenorphine reduces suicidal ideation.

Medication-Assisted Treatment for Opioid-Use Disorder

The United States is in the midst of a national opioid epidemic. Physicians are encouraged both to prevent and treat opioid-use disorders (OUDs). Although there are 3 Food and Drug Administration-approved medications to treat OUD (methadone, buprenorphine, and naltrexone) and there is ample evidence of their efficacy, they are not used as often as they should. We provide a brief review of the 3 primary medications used in the treatment of OUD. Using data from available medical literature, we synthesize existing knowledge and provide a framework for how to determine the optimal approach for outpatient management of OUD with medication-assisted treatments.

Single high-dose buprenorphine for opioid craving during withdrawal

Background

Opioid use disorder is one of the most prevalent addiction problems worldwide. Buprenorphine is used as a medication to treat this disorder, but in countries where buprenorphine is unavailable in combination with naloxone, diversion can be a problem if the medication is given outside a hospital setting.

Objective

The objective of this research is to evaluate the effect of a single, high dose of buprenorphine on craving in opioid-dependent patients over 5 days of abstinence from use of other opioids. The primary goal was to determine the safety and efficacy of buprenorphine during withdrawal in a hospital setting.

Methods

Ninety men who used opium, heroin, or prescribed opioids and met DSM-5 criteria for opioid use disorder (severe form) were randomized to three groups (n = 30 per group) to receive a single, sublingual dose of buprenorphine (32, 64, or 96 mg). The study was conducted in an inpatient psychiatric ward, with appropriate precautions and monitoring of respiratory and cardiovascular measures. Buprenorphine was administered when the patients were in moderate opiate withdrawal, as indicated by the presence of four to five symptoms. A structured clinical interview was conducted, and urine toxicology testing was performed at baseline. Self-reports of craving were obtained at baseline and on each of the 5 days after buprenorphine administration.

Findings

Craving decreased from baseline in each of the three groups (p < 0.0001), with a significant interaction between group and time (p < 0.038), indicating that groups with higher doses of buprenorphine had greater reduction.

Conclusions

A single, high dose of buprenorphine can reduce craving during opioid withdrawal; additional studies with follow-up are warranted to evaluate safety.

Buprenorphine MAT as an Imperfect Fix

Expanding buprenorphine access in the United States requires evidence-based decision-making that considers both the drug's potential dangers and its potential benefits. Risks associated with buprenorphine misuse and diversion highlight the need for careful, ongoing evaluation during each stage of increased access.

Opioid agonist treatment for pharmaceutical opioid dependent people

BACKGROUND

There are increasing concerns regarding pharmaceutical opioid 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.

OBJECTIVES

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

SEARCH METHODS

The search included the Cochrane Drugs and Alcohol Group's Specialised Register of Trials; the Cochrane Central Register of Controlled Trials (CENTRAL, 2015, Issue 5); PubMed (January 1966 to May 2015); EMBASE (Ovid) (January 1974 to May 2015); CINAHL (EBSCOhost) (1982 to May 2015); ISI Web of Science (to May 2014); and PsycINFO (Ovid) (1806 to May 2014).

SELECTION CRITERIA

We included randomised controlled trials 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 and2. full or partial opioid agonist maintenance versus placebo, detoxification only, or psychological treatment (without opioid agonist treatment).

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodological procedures.

MAIN RESULTS

We identified six randomised controlled trials that met inclusion criteria (607 participants).We found moderate quality evidence from two studies of no difference between methadone and buprenorphine in self reported opioid use (risk ratio (RR) 0.37, 95% confidence interval (CI) 0.08 to 1.63) or opioid positive urine drug tests (RR 0.81, 95% CI 0.56 to 1.18). There was low quality evidence from three studies of no difference in retention between buprenorphine and methadone maintenance treatment (RR 0.69, 95% CI 0.39 to 1.22). There was moderate quality evidence from two studies of no difference between methadone and buprenorphine on adverse events (RR 1.10, 95% CI 0.64 to 1.91).We found low quality evidence from three studies favouring maintenance buprenorphine treatment over detoxification or psychological treatment in terms of fewer opioid positive urine drug tests (RR 0.63, 95% CI 0.43 to 0.91) and self reported opioid use in the past 30 days (RR 0.54, 95% CI 0.31 to 0.93). There was no difference on days of unsanctioned opioid use (standardised mean difference (SMD) -0.31, 95% CI -0.66 to 0.04). There was moderate quality evidence favouring buprenorphine maintenance over detoxification or psychological treatment on retention in treatment (RR 0.33, 95% CI 0.23 to 0.47). There was moderate quality evidence favouring buprenorphine maintenance over detoxification or psychological treatment on adverse events (RR 0.19, 95% CI 0.06 to 0.57).The main weaknesses in the quality of the data was the use of open-label study designs.

AUTHORS' CONCLUSIONS

There was low to moderate quality evidence supporting the use of maintenance agonist pharmacotherapy for pharmaceutical opioid dependence. Methadone or buprenorphine appeared equally effective. Maintenance treatment with buprenorphine appeared more effective than detoxification or psychological treatments.Due to the overall low to moderate quality of the evidence and small sample sizes, there is the possibility that the further research may change these findings.

Medication-assisted treatment of opioid use disorder: review of the evidence and future directions

Medication-assisted treatment of opioid use disorder with physiological dependence at least doubles rates of opioid-abstinence outcomes in randomized, controlled trials comparing psychosocial treatment of opioid use disorder with medication versus with placebo or no medication. This article reviews the current evidence for medication-assisted treatment of opioid use disorder and also presents clinical practice imperatives for preventing opioid overdose and the transmission of infectious disease. The evidence strongly supports the use of agonist therapies to reduce opioid use and to retain patients in treatment, with methadone maintenance remaining the gold standard of care. Combined buprenorphine/naloxone, however, also demonstrates significant efficacy and favorable safety and tolerability in multiple populations, including youth and prescription opioid-dependent individuals, as does buprenorphine monotherapy in pregnant women. The evidence for antagonist therapies is weak. Oral naltrexone demonstrates poor adherence and increased mortality rates, although the early evidence looks more favorable for extended-release naltrexone, which has the advantages that it is not subject to misuse or diversion and that it does not present a risk of overdose on its own. Two perspectives-individualized treatment and population management-are presented for selecting among the three available Food and Drug Administration-approved maintenance therapies for opioid use disorder. The currently unmet challenges in treating opioid use disorder are discussed, as are the directions for future research.

Naltrexone implant treatment for buprenorphine dependence--Mauritian case series

Although substitution therapy with opiate agonist treatments such as methadone and buprenorphine has resulted in a reduction of illicit drug use related harm, such treatment has also resulted in severe problems in some countries where opioid-dependent individuals now inject illicitly sold buprenorphine or buprenorphine-naloxone instead of heroin. There is no approved treatment for buprenorphine dependence. Naltrexone is an opioid antagonist which has been used for the treatment of both alcohol and opioid dependencies. Although both buprenorphine and heroin resemble each other concerning their effects, buprenorphine has a higher affinity to opioid receptors than heroin. Therefore, it is not known if naltrexone can block the psychoactive effects of buprenorphine as it does for heroin. This paper presents observational case series data on the use of a sustained-release naltrexone implant for the treatment of buprenorphine dependence. To the authors' knowledge this is the first use of sustained-release naltrexone for this indication.

Buprenorphine maintenance versus placebo or methadone maintenance for opioid dependence

BACKGROUND

Buprenorphine maintenance treatment has been evaluated in randomised controlled trials against placebo medication, and separately as an alternative to methadone for management of opioid dependence.

OBJECTIVES

To evaluate buprenorphine maintenance compared to placebo and to methadone maintenance in the management of opioid dependence, including its ability to retain people in treatment, suppress illicit drug use, reduce criminal activity, and mortality.

SEARCH METHODS

We searched the following databases to January 2013: Cochrane Drugs and Alcohol Review Group Specialised Register, Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, Current Contents, PsycLIT, CORK, Alcohol and Drug Council of Australia, Australian Drug Foundation, Centre for Education and Information on Drugs and Alcohol, Library of Congress, reference lists of identified studies and reviews. We sought published/unpublished randomised controlled trials (RCTs) from authors.

SELECTION CRITERIA

Randomised controlled trials of buprenorphine maintenance treatment versus placebo or methadone in management of opioid-dependent persons.

DATA COLLECTION AND ANALYSIS

We used Cochrane Collaboration methodology.

MAIN RESULTS

We include 31 trials (5430 participants), the quality of evidence varied from high to moderate quality.There is high quality of evidence that buprenorphine was superior to placebo medication in retention of participants in treatment at all doses examined. Specifically, buprenorphine retained participants better than placebo: at low doses (2 - 6 mg), 5 studies, 1131 participants, risk ratio (RR) 1.50; 95% confidence interval (CI) 1.19 to 1.88; at medium doses (7 - 15 mg), 4 studies, 887 participants, RR 1.74; 95% CI 1.06 to 2.87; and at high doses (≥ 16 mg), 5 studies, 1001 participants, RR 1.82; 95% CI 1.15 to 2.90. However, there is moderate quality of evidence that only high-dose buprenorphine (≥ 16 mg) was more effective than placebo in suppressing illicit opioid use measured by urinanalysis in the trials, 3 studies, 729 participants, standardised mean difference (SMD) -1.17; 95% CI -1.85 to -0.49, Notably, low-dose, (2 studies, 487 participants, SMD 0.10; 95% CI -0.80 to 1.01), and medium-dose, (2 studies, 463 participants, SMD -0.08; 95% CI -0.78 to 0.62) buprenorphine did not suppress illicit opioid use measured by urinanalysis better than placebo.There is high quality of evidence that buprenorphine in flexible doses adjusted to participant need,was less effective than methadone in retaining participants, 5 studies, 788 participants, RR 0.83; 95% CI 0.72 to 0.95. For those retained in treatment, no difference was observed in suppression of opioid use as measured by urinalysis, 8 studies, 1027 participants, SMD -0.11; 95% CI -0.23 to 0.02 or self report, 4 studies, 501 participants, SMD -0.11; 95% CI -0.28 to 0.07, with moderate quality of evidence.Consistent with the results in the flexible-dose studies, in low fixed-dose studies, methadone (≤ 40 mg) was more likely to retain participants than low-dose buprenorphine (2 - 6 mg), (3 studies, 253 participants, RR 0.67; 95% CI: 0.52 to 0.87). However, we found contrary results at medium dose and high dose: there was no difference between medium-dose buprenorphine (7 - 15 mg) and medium-dose methadone (40 - 85 mg) in retention, (7 studies, 780 participants, RR 0.87; 95% CI 0.69 to 1.10) or in suppression of illicit opioid use as measured by urines, (4 studies, 476 participants, SMD 0.25; 95% CI -0.08 to 0.58) or self report of illicit opioid use, (2 studies, 174 participants, SMD -0.82; 95% CI -1.83 to 0.19). Similarly, there was no difference between high-dose buprenorphine (≥ 16 mg) and high-dose methadone (≥ 85 mg) in retention (RR 0.79; 95% CI 0.20 to 3.16) or suppression of self-reported heroin use (SMD -0.73; 95% CI -1.08 to -0.37) (1 study, 134 participants).Few studies reported adverse events ; two studies compared adverse events statistically, finding no difference between methadone and buprenorphine, except for a single result indicating more sedation among those using methadone.

AUTHORS' CONCLUSIONS

Buprenorphine is an effective medication in the maintenance treatment of heroin dependence, retaining people in treatment at any dose above 2 mg, and suppressing illicit opioid use (at doses 16 mg or greater) based on placebo-controlled trials.However, compared to methadone, buprenorphine retains fewer people when doses are flexibly delivered and at low fixed doses. If fixed medium or high doses are used, buprenorphine and methadone appear no different in effectiveness (retention in treatment and suppression of illicit opioid use); however, fixed doses are rarely used in clinical practice so the flexible dose results are more relevant to patient care. Methadone is superior to buprenorphine in retaining people in treatment, and methadone equally suppresses illicit opioid use.

Pharmacokinetic drug interactions between drugs of abuse and antiretroviral medications: implications and management for clinical practice

Substance abuse and HIV/AIDS are two of the most serious, yet treatable diseases worldwide. Global access to HIV treatment continues to expand. In settings where both active illicit drug use and HIV treatment are concurrent, potentional problematic pharmacokinetic drug interactions may arise and complicate therapy. Clinical case series and carefully controlled pharmacokinetic interaction studies have been conducted between only a few drugs of abuse and approved antiretroviral therapies. Important pharmacokinetic drug interactions have been described for benzodiazepines, 3,4-methylenedioxymethamphetamine, methadone and buprenorphine; however, most have not been studied and few well-controlled studies have been conducted to adequately address the clinical implications of these interactions. The metabolism of drugs of abuse, description of the known interactions, and clinical implications and management of these interactions are reviewed. Certain interactions between drugs of abuse and antiretroviral therapies are known and others are likely based upon shared metabolic pathways. These may result in important clinical consequences. To optimize care, clinicians must be alert, knowledgeable about known and possible interactions and equipped to clinically manage the medical consequences. Moreover, there is considerable need for carefully controlled studies in this important and emerging area.

Retention of participants in medication-assisted programs in low- and middle-income countries: an international systematic review

BACKGROUND AND AIMS

Medication-assisted treatment (MAT) is a key component in overdose prevention, reducing illicit opiate use and risk of blood-borne virus infection. By retaining participants in MAT programs for longer periods of time, more noticeable and permanent changes in drug use, risk behavior and quality of life can be achieved. Many studies have documented retention in MAT programs in high-income countries, using a 50% average 12-month follow-up retention rate as a marker for a successful MAT program. This study contributes to a systematic understanding of how successful programs have been in retaining participants in low- and middle-income countries (LMIC) over time.

METHODS

Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we conducted a systematic literature search to identify MAT program studies that documented changes in retention over time for participants in buprenorphine and methadone programs in LMIC. Retention was measured for participants by length of follow-up, type of MAT and treatment dosage.

RESULTS

There were 58 MAT program studies, with 27 047 participants eligible for inclusion in the review. Overall average retention after 12 months was 54.3% [95% confidence interval (CI) = 46.2, 63.7%]. Overall average retention was moderately good for both buprenorphine (48.3%, 95% CI = 22.1, 74.6%) and methadone (56.6%, 95% CI = 45.9%, 67.3%) after 12 months of treatment. Among programs using methadone there was no statistically significant difference in average retention by dosage level, and the 10 highest and lowest dosage programs obtained similar average retention levels after 12 months.

CONCLUSION

Medication-assisted treatment programs in low- and middle-income countries achieve an average 50% retention rate after 12 months, with wide variation across programs but little difference between those using buprenorphine versus methadone.

Methadone and buprenorphine-naloxone are effective in reducing illicit buprenorphine and other opioid use, and reducing HIV risk behavior--outcomes of a randomized trial

AIMS

Determine the extent to which buprenorphine injectors continue treatment with buprenorphine-naloxone or methadone, and the impact of these treatments on substance use and HIV risk in the Republic of Georgia.

METHODS

Randomized controlled 12-week trial of daily-observed methadone or buprenorphine-naloxone followed by a dose taper, referral to ongoing treatment, and follow-up at week 20 at the Uranti Clinic in Tbilisi, Republic of Georgia. Eighty consenting treatment-seeking individuals (40/group) aged 25 and above who met ICD-10 criteria for opioid dependence with physiologic features and reported injecting buprenorphine 10 or more times in the past 30 days. Opioid use according to urine tests and self-reports, treatment retention, and HIV risk behavior as determined by the Risk Assessment Battery.

RESULTS

Mean age of participants was 33.7 (SD5.7), 4 were female, mean history of opioid injection use was 5.8 years (SD4.6), none were HIV+ at intake or at the 12-week assessment and 73.4% were HCV+. Sixty-eight participants (85%) completed the 12-week medication phase (33 from methadone and 35 from buprenorphine/naloxone group); 37 (46%) were in treatment at the 20-week follow-up (21 from methadone and 16 from the buprenorphine/naloxone group). In both study arms, treatment resulted in a marked reduction in unprescribed buprenorphine, other opioid use, and HIV injecting risk behavior with no clinically significant differences between the two treatment arms.

CONCLUSIONS

Daily observed methadone or buprenorphine-naloxone are effective treatments for non-medical buprenorphine and other opioid use in the Republic of Georgia and likely to be useful for preventing HIV infection.

Maintenance medication for opiate addiction: the foundation of recovery

Illicit use of opiates is the fastest growing substance use problem in the United States, and the main reason for seeking addiction treatment services for illicit drug use throughout the world. It is associated with significant morbidity and mortality related to human immunodeficiency virus, hepatitis C, and overdose. Treatment for opiate addiction requires long-term management. Behavioral interventions alone have extremely poor outcomes, with more than 80% of patients returning to drug use. Similarly poor results are seen with medication-assisted detoxification. This article provides a topical review of the three medications approved by the Food and Drug Administration for long-term treatment of opiate dependence: the opioid-agonist methadone, the partial opioid-agonist buprenorphine, and the opioid-antagonist naltrexone. Basic mechanisms of action and treatment outcomes are described for each medication. Results indicate that maintenance medication provides the best opportunity for patients to achieve recovery from opiate addiction. Extensive literature and systematic reviews show that maintenance treatment with either methadone or buprenorphine is associated with retention in treatment, reduction in illicit opiate use, decreased craving, and improved social function. Oral naltrexone is ineffective in treating opiate addiction, but recent studies using extended-release naltrexone injections have shown promise. Although no direct comparisons between extended-release naltrexone injections and either methadone or buprenorphine exist, indirect comparison of retention shows inferior outcome compared with methadone and buprenorphine. Further work is needed to directly compare each medication and determine individual factors that can assist in medication selection. Until such time, selection of medication should be based on informed choice following a discussion of outcomes, risks, and benefits of each medication.

Lack of reduction in buprenorphine injection after introduction of co-formulated buprenorphine/naloxone to the Malaysian market

BACKGROUND

Diversion of buprenorphine (BPN) has been described in settings where it is legally prescribed and has resulted in increasing concern. To address this concern, co-formulation of buprenorphine/naloxone (BPN/NLX) replaced buprenorphine alone in Malaysia in December 2006.

METHODS

To assess the significance of BPN/NLX introduction, 41 BPN/NLX injectors in Kuala Lumpur, Malaysia were recruited using a modified snowball recruitment technique.

RESULTS

In January 2007, all subjects had previously injected BPN alone. During the transition from injecting BPN alone to co-formulated BPN/NLX, the mean daily BPN injection dose increased from 1.88 mg (range 1.0-4.0 mg) to 2.49 mg/day (p < .001). Overall, 18 (44%) subjects increased their daily amount of injection while 22 (54%) had no change in dose; only one subject reduced the amount of injection. Development of opioid withdrawal symptoms was the primary outcome, however the only symptom that was significantly associated with BPN/NLX dosage was the report of "stomach pains" (p = .01). In logistic regression analysis, the development of opioid withdrawal symptoms was associated with increased benzodiazepine injection and increased syringe sharing.

CONCLUSION AND SCIENTIFIC SIGNIFICANCE

These data suggests that the introduction of BPN/NLX did not reduce injection related risk behaviors such as syringe sharing and was associated with increased benzodiazepine use. Evidence-based approaches to treat BPN injection are urgently needed.

Buprenorphine maintenance versus placebo or methadone maintenance for opioid dependence

BACKGROUND

Buprenorphine has been reported as an alternative to methadone for maintenance treatment of opioid dependence, but differing results are reported concerning its relative effectiveness indicating the need for an integrative review.

OBJECTIVES

To evaluate the effects of buprenorphine maintenance against placebo and methadone maintenance in retaining patients in treatment and in suppressing illicit drug use.

SEARCH STRATEGY

We searched the following databases up to October 2006: Cochrane Drugs and Alcohol Review Group Register, the Cochrane Controlled Trials Register, MEDLINE, EMBASE, Current Contents, Psychlit, CORK , Alcohol and Drug Council of Australia, Australian Drug Foundation, Centre for Education and Information on Drugs and Alcohol, Library of Congress databases, reference lists of identified studies and reviews, authors were asked about any other published or unpublished relevant RCT.

SELECTION CRITERIA

Randomised clinical trials of buprenorphine maintenance versus placebo or methadone maintenance.

DATA COLLECTION AND ANALYSIS

Authors separately and independently evaluated the papers and extracted data for meta-analysis.

MAIN RESULTS

Twenty four studies met the inclusion criteria (4497 participants), all were randomised clinical trials, all but six were double-blind. The method of allocation concealment was not clearly described in the majority (20) of the studies, but where it was reported the methodological quality was good. Buprenorphine was statistically significantly superior to placebo medication in retention of patients in treatment at low doses (RR=1.50; 95% CI: 1.19 - 1.88), medium (RR=1.74; 95% CI: 1.06 - 2.87), and high doses (RR=1.74; 95% CI: 1.02 - 2.96). The high statistical heterogeneity prevented the calculation of a cumulative estimate. However, only medium and high dose buprenorphine suppressed heroin use significantly above placebo. Buprenorphine given in flexible doses was statistically significantly less effective than methadone in retaining patients in treatment (RR= 0.80; 95% CI: 0.68 - 0.95), but no different in suppression of opioid use for those who remained in treatment. Low dose methadone is more likely to retain patients than low dose buprenorphine (RR= 0.67; 95% CI: 0.52 - 0.87). Medium dose buprenorphine does not retain more patients than low dose methadone, but may suppress heroin use better. There was no advantage for medium dose buprenorphine over medium dose methadone in retention (RR=0.79; 95% CI:0.64 - 0.99) and medium dose buprenorphine was inferior in suppression of heroin use.

AUTHORS' CONCLUSIONS

Buprenorphine is an effective intervention for use in the maintenance treatment of heroin dependence, but it is less effective than methadone delivered at adequate dosages.

Management of relapse in naltrexone maintenance for heroin dependence

Opioid dependence is a growing public health problem. Maintenance on the antagonist naltrexone for clinic- or office-based treatment of opioid dependence is plagued by high rates of relapse. This paper identifies critical determinants of lapses to opioid use during naltrexone maintenance. Time retained in treatment was examined as a function of whether lapses to opioid use occurred while adherent to naltrexone (blocked use), or after having missed naltrexone doses (unblocked).

METHOD

Participants (N=83) met DSM-IV criteria for opioid dependence and identified a significant other willing to participate in their treatment. Following inpatient detoxification, participants were enrolled in a 26-week outpatient course of therapy and naltrexone maintenance.

RESULTS

Patients with unblocked use had a very high rate of dropout (10% retained at 6 months), dropout usually occurring within 2 weeks after unblocked use. Patients with only blocked use had less dropout (33% retained at 6 months). However, episodes of blocked use were often followed by unblocked use and dropout.

CONCLUSIONS

During naltrexone maintenance for opioid dependence unblocked opioid use calls for immediate intervention, such as detoxification or switching to the partial agonist buprenorphine. Episodes of blocked use warrant increased clinical attention, such as direct observation of naltrexone ingestion, increased dose, or increased intensity of treatment contact. Maintenance on oral naltrexone is a fragile treatment because it is so easily undermined by episodes of opioid use while non-compliant. New long-acting injectable or implantable formulations of naltrexone may address this limitation and should be investigated for treatment of opioid dependence.

Sustained-release naltrexone: novel treatment for opioid dependence

The devastating costs of opioid abuse and dependence underscore the need for effective treatments for these disorders. At present, several different maintenance medications exist for treating opioid dependence, including methadone, buprenorphine and naltrexone. Of these, naltrexone is the only one that possesses no opioid agonist effects. Instead, naltrexone occupies opioid receptors and prevents or reverses the effects produced by opioid agonists. Despite its clear pharmacologic effectiveness, its clinical effectiveness in treating opioid dependence has been disappointing, primarily due to non-compliance with taking the medication. However, the recent availability of sustained-release formulations of naltrexone has renewed interest in this medication. The present paper describes the development of sustained-release naltrexone formulations and discusses the clinical issues associated with their use in treating opioid dependence.

Naltrexone and buprenorphine combination in the treatment of opioid dependence

Naltrexone treatment has demonstrated some advantages for special populations of heroin addicted individuals, but patients' compliance seems to be very poor, with a low adherence and low retention rate. Kappa-opioid system overdrive seems to contribute to opioid protracted abstinence syndrome, with dysphoria and psychosomatic symptoms during naltrexone treatment. The objective of this observational study was to determine the effectiveness of a functional k antagonist in improving naltrexone treatment outcome. A partial mu agonist/kappa antagonist (buprenorphine) and a mu antagonist (naltrexone) were combined during a 12 weeks protocol, theoretically leaving k antagonism as the major medication effect. Sixty patients were submitted to outpatient rapid detoxification utilizing buprenorphine and opioid antagonists. Starting on the fifth day, 30 patients (group A) received naltrexone alone. Alternatively, 30 patients (group B) received naltrexone (50mg oral dose) plus buprenorphine (4 mg sublingual) for the 12 weeks of the observational study. The endpoints of the study were: retention in treatment, negative urinalyses, changes in psychological symptoms (Symptom Checklist-90 Revised: SCL-90) and craving scores (visual analysis scale (VAS)). Thirty-four subjects (56.67%) completed the 12 weeks study. Twenty-one patients (35.0%) had all urine samples negative for opiates and cocaine. nine subjects (15.0%) had urine samples negative for cocaine and opiates for the last 4 weeks of the study. five subjects (8.3%) continued to use cocaine during the 12 weeks of the study. No significant change in pupillary diameter after buprenorphine administration was evidenced during clinical observations from baseline across the weekly measurements. Retention rates in group A (naltrexone) and group B (naltrexone + buprenorphine) at week 12 were respectively 40% (12 patients) and 73.33% (22 patients), with a significant difference in favour of group B (p= 0.018). Patients treated with naltrexone in combination with buprenorphine (B patients) showed a significantly lower rate of positive urines for morphine (4.45%) and cocaine metabolites (9.09%) than those treated with naltrexone alone (A) (25%, morphine; 33.33% cocaine) (p< 0.05; p< 0.05). Irritability, depression, tiredness, psychosomatic symptoms and craving scores decreased significantly less in Group A patients than in group B patients. The dysfunction of opioid system with kappa receptors hyper-activation provoked by heroin exposure, probably underlying dysphoric and psychosomatic symptoms during naltrexone treatment, seems to be counteracted, at least in part, by buprenorphine. The combination of buprenorphine and naltrexone may significantly improve the outcome of opioid antagonists treatment in terms of retention, negative urinalyses, and reduced dysphoria, mood symptoms and craving.

Diretrizes para o tratamento de pacientes com síndrome de dependência de opióides no Brasil

Existe uma prevalência relativamente baixa do uso de ópioides no Brasil, em particular envolvendo o uso não médico da codeína e de xaropes que contêm opióides. No entanto, a síndrome de dependência apresenta um significativo impacto total na mortalidade e morbidade. Nos últimos 20 anos, o avanço científico tem modificado nosso entendimento sobre a natureza da adição aos opióides e os variados tratamentos possíveis. A adição é uma doença crônica tratável se o tratamento for realizado e adaptado tendo em vista as necessidades do paciente específico. Há, de um fato, um conjunto de tratamentos que podem efetivamente reduzir o uso da droga, ajudar a gerenciar a fissura pela droga, prevenir recaídas e recuperar as pessoas para o funcionamento social produtivo. O tratamento da dependência de drogas será parte de perspectivas de longo prazo do ponto de vista médico, psicológico e social. Esta diretriz almeja fornecer um guia para os psiquiatras e outros profissionais de saúde que tratam de pacientes com Síndrome de Dependência de Opióides. Ela tece comentários sobre o tratamento somático e psicossocial que é utilizado nesses pacientes e revisa as evidências científicas e seu poder. Da mesma forma, os aspectos históricos, epidemiológicos e neurobiológicos da dependência de opióides são revisados.