Implementing Buprenorphine Treatment in Community Settings in Australia: Experiences from the Buprenorphine Implementation Trial

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.

Flexible Buprenorphine/Naloxone Model of Care for Reducing Opioid Use in Individuals With Prescription-Type Opioid Use Disorder: An Open-Label, Pragmatic, Noninferiority Randomized Controlled Trial

OBJECTIVE

Extensive exposure to prescription-type opioids has resulted in major harm worldwide, calling for better-adapted approaches to opioid agonist therapy. The authors aimed to determine whether flexible take-home buprenorphine/naloxone is as effective as supervised methadone in reducing opioid use in prescription-type opioid consumers with opioid use disorder.

METHODS

This seven-site, pan-Canadian, 24-week, pragmatic, open-label, noninferiority, two-arm parallel randomized controlled trial involved treatment-seeking adults with prescription-type opioid use disorder. Participants were randomized in a 1:1 ratio to treatment with sublingual buprenorphine/naloxone (target dosage, 8 mg/2 mg to 24 mg/6 mg per day; flexible take-home dosing) or oral methadone (≈60-120 mg/day; closely supervised). The primary outcome was the proportion of opioid-free urine drug screens over 24 weeks (noninferiority margin, 15%). All randomized participants were analyzed, excluding one who died shortly after randomization, for the primary analysis (modified intention-to-treat analysis).

RESULTS

Of 272 participants recruited (mean age, 39 years [SD=11]; 34.2% female), 138 were randomized to buprenorphine/naloxone and 134 to methadone. The mean proportion of opioid-free urine drug screens was 24.0% (SD=34.4) in the buprenorphine/naloxone group and 18.5% (SD=30.5) in the methadone group, with a 5.6% adjusted mean difference (95% CI=-0.3, +∞). Participants in the buprenorphine/naloxone group had 0.47 times the odds (95% CI=0.24, 0.90) of being retained in the assigned treatment compared with those in the methadone group. Overall, 24 drug-related adverse events were reported (12 in the buprenorphine/naloxone group [N=8/138; 5.7%] and 12 in the methadone group [N=12/134; 9.0%]) and mostly included withdrawal, hypogonadism, and overdose.

CONCLUSIONS

The buprenorphine/naloxone flexible model of care was safe and noninferior to methadone in reducing opioid use among people with prescription-type opioid use disorder. This flexibility could help expand access to opioid agonist therapy and reduce harms in the context of the opioid overdose crisis.

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).

Considerations of Australian community pharmacists in the provision and implementation of cognitive pharmacy services: a qualitative study

Background

Australian federally-funded cognitive pharmacy services (CPS) (e.g. medication management and reconciliation services) have not been translated into practice consistently. These health services are purportedly accessible across all Australian community pharmacies, yet are not delivered as often as pharmacists would like. There are international indicators that pharmacists lack the complete behavioural control required to prioritise CPS, despite their desire to deliver them. This requires local investigation.

Objective

To explore Australian pharmacists’ perspectives [1] as CPS providers on the micro level, and [2] on associated meso and macro level CPS implementation issues.

Methods

Registered Australian community pharmacists were recruited via professional organisations and snowball sampling. Data were collected via an online demographic survey and semi-structured interviews until data saturation was reached. Interview transcripts were de-identified then verified by participants. Content analysis was performed to identify provider perspectives on the micro level. Framework analysis using RE-AIM was used to explore meso and macro implementation issues.

Results

Twenty-three participants across Australia gave perspectives on CPS provision. At the micro level, pharmacists did not agree on a single definition of CPS. However, they reported complexity in interactional work and patient considerations, and individual pharmacist factors that affected them when deciding whether to provide CPS. There was an overall deficiency in pharmacy workplace resources reported to be available for implementation and innovation. Use of an implementation evaluation framework suggested CPS implementation is lacking sufficient structural support, whilst reach into target population, service consistency and maintenance for CPS were not specifically considered by pharmacists.

Conclusions

This analysis of pharmacist CPS perspectives suggests slow uptake may be due to a lack of evidence-based, focused, multi-level implementation strategies that take ongoing pharmacist role transition into account. Sustained change may require external change management and implementation support, engagement of frontline clinicians in research, and the development of appropriate pharmacist practice models to support community pharmacists in their CPS roles.

Trial registration

This study was not a clinical intervention trial. It was approved by the University of Technology Sydney Human Research Ethics Committee (UTS HREC 19–3417) on the 26th of April 2019.

Office-Based Methadone Treatment for Opioid Use Disorder and Pharmacy Dispensing: A Scoping Review

OBJECTIVE

The authors conducted a scoping review to survey the evidence landscape for studies that assessed outcomes of treating patients with opioid use disorder with methadone in office-based settings.

METHODS

Ovid MEDLINE and the Cochrane Database of Systematic Reviews were searched, and reference lists were reviewed to identify additional studies. Studies were eligible if they focused on methadone treatment in office-based settings conducted in the United States or other highly developed countries and reported outcomes (e.g., retention in care). Randomized trials and controlled observational studies were prioritized; uncontrolled and descriptive studies were included when stronger evidence was unavailable. One investigator abstracted key information, and a second verified data. A scoping review approach broadly surveyed the evidence, and therefore study quality was not rated formally.

RESULTS

Eighteen studies of patients treated with office-based methadone were identified, including six trials, eight observational studies, and four additional articles discussing use of pharmacies to dispense methadone. Studies on office-based methadone treatment, including primary care-based dispensing, were limited but consistently found that stable methadone patients valued office-based care and remained in care with low rates of drug use; outcomes were similar compared with stable patients in regular care. Office-based methadone treatment was associated with higher treatment satisfaction and quality of life. Limitations included underpowered comparisons and small samples.

CONCLUSIONS

Limited research suggests that office-based methadone treatment and pharmacy dispensing could enhance access to methadone treatment for patients with opioid use disorder without adversely affecting patient outcomes and, potentially, inform modifications to federal regulations. Research should assess the feasibility of office-based care for less stable patients.

Effects of opioid rotation to buprenorphine/naloxone on pain, pain thresholds, pain tolerance, and quality of life in patients with chronic pain and opioid use disorder

ABSTRACT

Long-term opioid use in patients with chronic noncancer pain (CNCP) can lead to opioid use disorder (OUD) and has been associated with hyperalgesia and reduced quality of life (QoL). Studies suggest antihyperalgesic properties of buprenorphine, and buprenorphine or naloxone (BuNa) has shown beneficial effects on QoL in patients with OUD without CNCP. This study investigated the added value of BuNa in patients with CNCP with OUD on self-reported pain, pain thresholds, pain tolerance, and QoL. In the current study, 43 outpatients with CNCP and OUD were included for inpatient conversion from full μ-receptor agonist opioids to BuNa. Self-reported pain, pain thresholds, pain tolerance, and QoL were determined at baseline and after 2 months of follow-up, using, respectively, a Visual Analogue Scale (VAS-pain and VAS-QoL), quantitative sensory testing, and EuroQol-5 dimensions. In total, 37 participants completed the protocol, and their data were analyzed. The mean VAS-pain score decreased from 51.3 to 37.2 (27.5%, F = 3.3; P = 0.044), whereas the pressure pain threshold and electric pain threshold or tolerance increased after substitution (F = 7.8; P = 0.005 and F = 44.5; P < 0.001, respectively), as well as QoL (EuroQol-5 dimensions questionnaire: F = 10.4; P = 0.003 and VAS-QoL: F = 4.4; P = 0.043). We found that conversion of full μ-receptor agonists to BuNa, in patients with CNCP with OUD, was accompanied with lower self-reported pain, higher pain thresholds, higher pain tolerance, and improved QoL. Despite several study limitations, these data suggest that BuNa might be of value in patients with CNCP with OUD. Future studies should investigate long-term effects of BuNa in randomized trials.

A call for consensus in defining efficacy in clinical trials for opioid addiction: combined results from a systematic review and qualitative study in patients receiving pharmacological assisted therapy for opioid use disorder

Background

Given the complex nature of opioid addiction treatment and the rising number of available opioid substitution and antagonist therapies (OSAT), there is no ‘gold standard’ measure of treatment effectiveness, and each successive trial measures a different set of outcomes which reflect success in arbitrary or opportune terms. We sought to describe the variation in current outcomes employed across clinical trials for opioid addiction, as well as determine whether a discrepancy exists between the treatment targets that patients consider important and how treatment effectiveness is measured in the literature.

Methods

We searched nine commonly used databases (e.g., EMBASE, MEDLINE) from inception to August 1, 2015. Outcomes used across trials were extracted and categorized according to previously established domains. To evaluate patient-reported goals of treatment, semi-structured interviews were conducted with 18 adults undergoing methadone treatment.

Results

We identified 60 trials eligible for inclusion. Once outcomes were categorized into eight broad domains (e.g., abstinence/substance abuse), we identified 21 specific outcomes with furthermore 53 subdomains and 118 measurements. Continued opioid use and treatment retention were the most commonly reported measures (46%, n = 28). The majority of patients agreed that abstinence from opioids was a primary goal in their treatment, although they also stressed goals under-reported in clinical trials.

Conclusions

There is inconsistency in the measures used to evaluate the effectiveness of OSATs. Individual and population level decision making is being guided by a standard of effect considered useful to researchers yet in direct conflict with what patients deem important.

Trial registration

PROSPERO, CRD42013006507.

Progress in agonist therapy for substance use disorders: Lessons learned from methadone and buprenorphine

Substance use disorders (SUD) are serious public health problems worldwide. Although significant progress has been made in understanding the neurobiology of drug reward and the transition to addiction, effective pharmacotherapies for SUD remain limited and a majority of drug users relapse even after a period of treatment. The United States Food and Drug Administration (FDA) has approved several medications for opioid, nicotine, and alcohol use disorders, whereas none are approved for the treatment of cocaine or other psychostimulant use disorders. The medications approved by the FDA for the treatment of SUD can be divided into two major classes - agonist replacement therapies, such as methadone and buprenorphine for opioid use disorders (OUD), nicotine replacement therapy (NRT) and varenicline for nicotine use disorders (NUD), and antagonist therapies, such as naloxone for opioid overdose and naltrexone for promoting abstinence. In the present review, we primarily focus on the pharmacological rationale of agonist replacement strategies in treatment of opioid dependence, and the potential translation of this rationale to new therapies for cocaine use disorders. We begin by describing the neural mechanisms underlying opioid reward, followed by preclinical and clinical findings supporting the utility of agonist therapies in the treatment of OUD. We then discuss recent progress of agonist therapies for cocaine use disorders based on lessons learned from methadone and buprenorphine. We contend that future studies should identify agonist pharmacotherapies that can facilitate abstinence in patients who are motivated to quit their illicit drug use. Focusing on those that are able to achieve abstinence from cocaine will provide a platform to broaden the effectiveness of medication and psychosocial treatment strategies for this underserved population. This article is part of the Special Issue entitled 'New Vistas in Opioid Pharmacology'.

Primary care models for treating opioid use disorders: What actually works? A systematic review

Background

Primary care-based models for Medication-Assisted Treatment (MAT) have been shown to reduce mortality for Opioid Use Disorder (OUD) and have equivalent efficacy to MAT in specialty substance treatment facilities.

Objective

The objective of this study is to systematically analyze current evidence-based, primary care OUD MAT interventions and identify program structures and processes associated with improved patient outcomes in order to guide future policy and implementation in primary care settings.

Data sources

PubMed, EMBASE, CINAHL, and PsychInfo.

Methods

We included randomized controlled or quasi experimental trials and observational studies evaluating OUD treatment in primary care settings treating adult patient populations and assessed structural domains using an established systems engineering framework.

Results

We included 35 interventions (10 RCTs and 25 quasi-experimental interventions) that all tested MAT, buprenorphine or methadone, in primary care settings across 8 countries. Most included interventions used joint multi-disciplinary (specialty addiction services combined with primary care) and coordinated care by physician and non-physician provider delivery models to provide MAT. Despite large variability in reported patient outcomes, processes, and tasks/tools used, similar key design factors arose among successful programs including integrated clinical teams with support staff who were often advanced practice clinicians (nurses and pharmacists) as clinical care managers, incorporating patient “agreements,” and using home inductions to make treatment more convenient for patients and providers.

Conclusions

The findings suggest that multidisciplinary and coordinated care delivery models are an effective strategy to implement OUD treatment and increase MAT access in primary care, but research directly comparing specific structures and processes of care models is still needed.

Effectiveness and cost-effectiveness of unsupervised buprenorphine-naloxone for the treatment of heroin dependence in a randomized waitlist controlled trial

BACKGROUND

Access to opioid agonist treatment can be associated with extensive waiting periods with significant health and financial burdens. This study aimed to determine whether patients with heroin dependence dispensed buprenorphine-naloxone weekly have greater reductions in heroin use and related adverse health effects 12-weeks after commencing treatment, compared to waitlist controls and to examine the cost-effectiveness of this strategy.

METHODS

An open-label waitlist RCT was conducted in an opioid treatment clinic in Newcastle, Australia. Fifty patients with DSM-IV-TR heroin dependence (and no other substance dependence) were recruited. The intervention group (n=25) received take-home self-administered sublingual buprenorphine-naloxone weekly (mean dose, 22.7±5.7mg) and weekly clinical review. Waitlist controls (n=25) received no clinical intervention. The primary outcome was heroin use (self-report, urine toxicology verified) at weeks four, eight and 12. The primary cost-effectiveness outcome was incremental cost per additional heroin-free-day.

RESULTS

Outcome data were available for 80% of all randomized participants. Across the 12-weeks, treatment group heroin use was on average 19.02days less/month (95% CI -22.98, -15.06, p<0.0001). A total 12-week reduction in adjusted costs including crime of $A5,722 (95% CI 3299, 8154) in favor of treatment was observed. Excluding crime, incremental cost per heroin-free-day gained from treatment was $A18.24 (95% CI 4.50, 28.49).

CONCLUSION

When compared to remaining on a waitlist, take-home self-administered buprenorphine-naloxone treatment is associated with significant reductions in heroin use for people with DSM-IV-TR heroin dependence. This cost-effective approach may be an efficient strategy to enhance treatment capacity.

Opioid substitution and antagonist therapy trials exclude the common addiction patient: a systematic review and analysis of eligibility criteria

BACKGROUND

Eligibility criteria that result in the exclusion of a substantial number of patients from randomized trials jeopardize the generalizability of treatment effect to much of the clinical population. This is important when evaluating opioid substitution and antagonist therapies (OSATs), especially given the challenges associated with treating the opioid-dependent population. We aimed to identify OSAT trials' eligibility criteria, quantify the percentage of the clinical population excluded by these criteria, and determine how OSAT guidelines incorporate evidence from these trials.

METHODS

We performed a systematic review to identify the eligibility criteria used across trials. We searched Medline, EMBASE, PsycINFO, Web of Science, Cochrane Library, Cochrane Clinical Trials Registry (CTR), World Health Organization International CTR Platform Search Portal, and the National Institutes of Health CTR databases from inception to January 1, 2014. To quantify the effect of trials' eligibility criteria on generalizability, we applied these criteria to data from an observational study of opioid-dependent patients (n = 394). We then accessed the Canadian, American, British, and World Health Organization (WHO) OSAT guidelines to evaluate how evidence is used in the recommendations.

RESULTS

Among the 60 trials identified the majority (≥50 % of trials) exclude patients with psychiatric (60 %) and physical comorbidity (51.7 %). Additionally, we found 19 trials exclude patients with current alcohol/substance-use problems (31.7 %), and 29 (48.3 %) exclude patients taking psychotropic medications. These criteria were restrictive and in some cases rendered 70 % of the observational sample ineligible. North American OSAT guidelines made strong recommendations supported by evidence with poor generalizability. National Institute of Health and Care Excellence (NICE) and WHO guidelines for opioid misuse provide a critical assessment of the literature used to inform their recommendations.

CONCLUSIONS

Trials assessing OSATs often exclude patients with concurrent disorders. If the excluded patients respond differently to treatment, results from these trials are likely to overestimate the true effectiveness of OSATs. North American guidelines should consider these limitations when drafting clinical recommendations.

Impact of Chronic Pain on Treatment Prognosis for Patients with Opioid Use Disorder: A Systematic Review and Meta-analysis

BACKGROUND

While a number of pharmacological interventions exist for the treatment of opioid use disorder, evidence evaluating the effect of pain on substance use behavior, attrition rate, and physical or mental health among these therapies has not been well established. We aim to evaluate these effects using evidence gathered from a systematic review of studies evaluating chronic non-cancer pain (CNCP) in patients with opioid use disorder.

METHODS

We searched the Medline, EMBASE, PubMed, PsycINFO, Web of Science, Cochrane Database of Systematic Reviews, ProQuest Dissertations and theses Database, Cochrane Central Register of Controlled Trials, World Health Organization International Clinical Trials Registry Platform Search Portal, and National Institutes for Health Clinical Trials Registry databases to identify articles evaluating the impact of pain on addiction treatment outcomes for patients maintained on opioid agonist therapy.

RESULTS

Upon screening 3,540 articles, 14 studies with a combined sample of 3,128 patients fulfilled the review inclusion criteria. Results from the meta-analysis suggest that pain has no effect on illicit opioid consumption [pooled odds ratio (pOR): 0.70, 95%CI 0.41–1.17; I² = 0.0] but a protective effect for reducing illicit non-opioid substance use (pOR: 0.57, 95%CI 0.41–0.79; I² = 0.0). Studies evaluating illicit opioid consumption using other measures demonstrate pain to increase the risk for opioid abuse. Pain is significantly associated with the presence of psychiatric disorders (pOR: 2.18; 95%CI 1.6, 2.9; I² = 0.0%).

CONCLUSION

CNCP may increase risk for continued opioid abuse and poor psychiatric functioning. Qualitative synthesis of the findings suggests that major methodological differences in the design and measurement of pain and treatment response outcomes are likely impacting the effect estimates.

The relative risk of fatal poisoning by methadone or buprenorphine within the wider population of England and Wales

OBJECTIVE

To examine the population-wide overdose risk emerging from the prescription of methadone and buprenorphine for opioid substitution treatment in England and Wales.

DESIGN

Retrospective administrative data study.

SETTING

National databases for England and Wales.

PARTICIPANTS/CASES

Drug-related mortality data were drawn from the Office for National Statistics, and prescription data for methadone and buprenorphine were obtained from the National Health Service for the years 2007-2012. During this 6-year period, a total of 2366 methadone-related deaths and 52 buprenorphine-related deaths were registered, corresponding to 17,333,163 methadone and 2,602,374 buprenorphine prescriptions issued. The analysis encompassed poisoning deaths among members of the wider population of England and Wales who consumed, but were not prescribed these medications, in addition to patients prescribed methadone or buprenorphine.

MAIN OUTCOME MEASURES

Mortality risk: substance-specific overdose rate per 1000 prescriptions issued; relative risk ratio of methadone in relation to buprenorphine.

RESULTS

During the years 2007-2012, the pooled overdose death rate was 0.137/1000 prescriptions of methadone, compared to 0.022/1000 prescriptions of buprenorphine (including buprenorphine-naloxone). The analysis generated a relative risk ratio of 6.23 (95% CI 4.79 to 8.10) of methadone in relation to buprenorphine. UK Borders Agency data were taken into consideration and revealed that only negligible amounts of methadone and buprenorphine were seized on entering UK territory between 2007 and 2012, suggesting domestic diversion.

CONCLUSIONS

Our analysis of the relative safety of buprenorphine and methadone for opioid substitution treatment reveals that buprenorphine is six times safer than methadone with regard to overdose risk among the general population. Clinicians should be aware of the increased risk of prescribing methadone, and tighter regulations are needed to prevent its diversion.

Buprenorphine in the treatment of opioid addiction: opportunities, challenges and strategies

INTRODUCTION

Buprenorphine follows the success of methadone as another milestone in the history of treatment for opioid addiction. Buprenorphine can be used in an office-based setting where it is clearly effective, highly accepted by patients and has a favorable safety profile and less abuse potential. However, the adoption of buprenorphine treatment has been slow in the USA.

AREAS COVERED

This article first reviews the history of medication-assisted opioid addiction treatment and the current epidemic opioid addiction, followed by a review of the efficacy, pharmacology and clinical prescription of buprenorphine in office-based care. We then explore the possible barriers in using buprenorphine and the ways to overcome these barriers, including new formulations, educational programs and policy regulations that strike a balance between accessibility and reducing diversion.

EXPERT OPINION

Buprenorphine can align addiction treatment with treatments for other chronic medical illnesses. However, preventing diversion will require graduate and continuing medical education and integrated care models for delivery of buprenorphine to those in need.

The reinforcing and subjective effects of intravenous and intranasal buprenorphine in heroin users

Abuse of buprenorphine (BUP) by the intravenous (IV) route has been documented in several studies, and reports of intranasal (IN) abuse are increasing. However, no studies have directly compared the effects of BUP when it is administered intranasally and intravenously. The present secondary analysis used data from two separate studies to compare the reinforcing and subjective effects of IV and IN buprenorphine. One study evaluated IV buprenorphine (N=13) and the other evaluated IN buprenorphine (N=12). Participants were maintained on 2 mg sublingual (SL) BUP and tested with each intranasal or intravenous buprenorphine test dose (0 mg, 2 mg, 4 mg, 8 mg, and 16 mg). During morning laboratory sessions, participants received money (US $20) and sample doses of IN or IV BUP, and then completed subjective effects questionnaires. Later that day, they completed a self-administration task to receive 10% portions of the drug and/or money they previously sampled. In general, positive subjective ratings for both IV and IN BUP were significantly greater than placebo, with IV BUP having a greater effect than IN BUP. All active BUP doses (IV and IN) maintained significantly higher progressive ratio breakpoint values than placebo, but breakpoint values for IV BUP were greater than for IN BUP. Buprenorphine is an effective maintenance treatment for opioid dependence, valued for its ability to reduce the positive subjective effects of other opioids. Nevertheless, the present data demonstrate that in participants maintained on a low dose of SL BUP, the medication itself has abuse liability when used intravenously or intranasally.

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.

The effect of an electronic medicine dispenser on diversion of buprenorphine-naloxone-experience from a medium-sized Finnish city

Providing unobserved opioid substitution treatment (OST) safely is a major challenge. This study examined whether electronic medicine dispensers (EMDs) can reduce diversion of take-home buprenorphine-naloxone (BNX) in a medium-sized Finnish city. All BNX treated OST patients in Kuopio received their take-home BNX in EMDs for 4months. EMDs' effect on diversion was investigated using questionnaires completed by patients (n=37) and treatment staff (n=19), by survey at the local needle exchange service and by systematic review of drug screen data from the Kuopio University Hospital. The majority of patients (n=21, 68%) and treatment staff (n=11, 58%) preferred to use EMDs for the safe storage of tablets. Five patients (16%) declared that EMDs had prevented them from diverting BNX. However, EMDs had no detectable effect on the availability or origin of illegal BNX or on the hospital-treated buprenorphine-related health problems. EMDs may improve the safety of storage of take-home BNX, but their ability to prevent diversion needs further research.

Cost-effectiveness analysis of maintenance agonist treatments in the NEPOD

A total of 551 participants were randomized to treatment in three heroin-dependence treatment trials participating in the Australian National Evaluation of Pharmacotherapies for Opioid Dependence (NEPOD) project. A total of 272 patients (49%) received methadone maintenance, 238 (43%) received buprenorphine maintenance and 41 (7%) participants received levo-alpha-acetyl-methadol (LAAM). A total of 63% of participants in the methadone maintenance group were in treatment in the third month, with an average treatment episode lasting 69 days. This compares with 51% of participants in the buprenorphine maintenance group with an average treatment episode of 60 days and 71% of participants in the LAAM group with an average treatment episode of 75 days. The results of the cost-effectiveness analysis suggested that, for the primary outcome measure of imputed change in heroin-free days, compared with methadone maintenance, LAAM was the most cost-effective treatment, followed by buprenorphine maintenance. No statistically significant differences were found in the cost-effectiveness of methadone maintenance, buprenorphine maintenance and LAAM. Given the limited information available regarding the relative cost-effectiveness of pharmacotherapies for opioid maintenance treatment, the data reported herein provide valuable information to policy makers and treatment providers.

Two-year Experience with Buprenorphine-naloxone (Suboxone) for Maintenance Treatment of Opioid Dependence Within a Private Practice Setting

Office-based buprenorphine-naloxone (Suboxone) treatment in the United States has significantly improved access to safe and effective opioid-dependence therapy. Little data from physicians' experiences prescribing Suboxone in private offices have been available. This retrospective chart review describes a family practitioner's first 2 years of clinical experience prescribing Suboxone for opioid dependence to 71 patients in a private office. After directly observed rapid office dose induction, Suboxone prescriptions were given monthly after evidence of continued stability. Urine was screened regularly and patients were referred for counseling and other ancillary services. Patients averaged 32 years old, 4.3 years of opioid dependence, and were primarily white (93%) and employed (70%). Fifty-two percent used heroin primarily (most by injection), and 70% had no agonist substitution therapy history. Almost half (47%) paid for their own treatment. Compliance during dose induction was excellent. Suboxone maintenance doses averaged 10 (range, 2-24) mg per day. More than 80% of urine samples were opioid-negative after Suboxone treatment began, although urinalysis did not always include a test for oxycodone. Seventy-five percent had successful outcomes by remaining in Suboxone treatment (43%), tapering successfully (21%), transferring to methadone maintenance (7%), or inpatient treatment (4%). Fifty-eight percent reported receiving counseling. Almost all (85%) paid their fees on time. There were no safety, medication abuse, or diversion issues detected. Overall, office-based Suboxone therapy was easily implemented and the physician considered the experience excellent. Suboxone maintenance was associated with good treatment retention and significantly reduced opioid use, and it is helping to reach patients, including injection drug users, without histories of agonist substitution therapy.

A prospective, randomized, multicenter acceptability and safety study of direct buprenorphine/naloxone induction in heroin-dependent individuals

AIMS

To provide controlled data on direct induction with buprenorphine/naloxone (BNX) versus indirect buprenorphine (BPN)-to-BNX induction.

DESIGN

Phase 4, prospective, randomized, active-drug controlled, parallel-group trial consisting of a 2-day, double-blind, double-dummy induction phase followed by 26 days of open-label treatment with BNX.

SETTING

Nineteen sites in 10 European countries from March 2008 to December 2009.

PARTICIPANTS

A total of 187 opioid-dependent men and women ≥ 15 years of age.

MEASUREMENTS

The primary objective was assessment of patient response to direct and indirect BNX induction [proportion of patients receiving the scheduled 16-mg BNX dose on day 3 (i.e. first day post-induction)]. Secondary assessments included illicit drug use, treatment retention and compliance, withdrawal scale scores, and safety.

FINDINGS

Patient response to direct- versus indirect-BNX induction was similar [direct 91.4% (85/93) versus indirect 90.4% (85/94); 95% confidence interval (CI): -7.3%, 9.2%]. Rapid dose induction (16 mg of BPN equivalent on day 2) was acceptable and 72% of patients completed treatment (day 28). There were no significant differences in secondary measures across groups. An average BNX maintenance dose of 15.3 mg across groups was associated with substantial reductions in illicit opioid use and no self-reported intravenous misuse. Treatment compliance and retention rates were similar (98.5% and 81.3%, respectively). Treatment-emergent adverse event rates were comparable: 75% versus 74% for direct- versus indirect-induction groups, respectively.

CONCLUSIONS

Direct buprenorphine/naloxone induction was a safe and effective strategy for maintenance treatment of opioid dependence. Response to high-dose direct buprenorphine/naloxone induction appears to be similar to indirect buprenorphine-to-buprenorphine/naloxone induction and was not associated with reports of intravenous buprenorphine/naloxone misuse.

Treatment of medical, psychiatric, and substance-use comorbidities in people infected with HIV who use drugs

HIV-infected drug users have increased age-matched morbidity and mortality compared with HIV-infected people who do not use drugs. Substance-use disorders negatively affect the health of HIV-infected drug users, who also have frequent medical and psychiatric comorbidities that complicate HIV treatment and prevention. Evidence-based treatments are available for the management of substance-use disorders, mental illness, HIV and other infectious complications such as viral hepatitis and tuberculosis, and many non-HIV-associated comorbidities. Tuberculosis co-infection in HIV-infected drug users, including disease caused by drug-resistant strains, is acquired and transmitted as a consequence of inadequate prescription of antiretroviral therapy, poor adherence, and repeated interfaces with congregate settings such as prisons. Medication-assisted therapies provide the strongest evidence for HIV treatment and prevention efforts, yet are often not available where they are needed most. Antiretroviral therapy, when prescribed and adherence is at an optimum, improves health-related outcomes for HIV infection and many of its comorbidities, including tuberculosis, viral hepatitis, and renal and cardiovascular disease. Simultaneous clinical management of multiple comorbidities in HIV-infected drug users might result in complex pharmacokinetic drug interactions that must be adequately addressed. Moreover, interventions to improve adherence to treatment, including integration of health services delivery, are needed. Multifaceted, interdisciplinary approaches are urgently needed to achieve parity in health outcomes in HIV-infected drug users.

Abuse liability of intravenous buprenorphine/naloxone and buprenorphine alone in buprenorphine-maintained intravenous heroin abusers

BACKGROUND

Sublingual buprenorphine is an effective maintenance treatment for opioid dependence, yet intravenous buprenorphine misuse occurs. A buprenorphine/naloxone formulation was developed to mitigate this misuse risk. This randomized, double-blind, cross-over study was conducted to assess the intravenous abuse potential of buprenorphine/naloxone compared with buprenorphine in buprenorphine-maintained injection drug users (IDUs).

METHODS

Intravenous heroin users (n = 12) lived in the hospital for 8-9 weeks and were maintained on each of three different sublingual buprenorphine doses (2 mg, 8 mg, 24 mg). Under each maintenance dose, participants completed laboratory sessions during which the reinforcing and subjective effects of intravenous placebo, naloxone, heroin and low and high doses of buprenorphine and buprenorphine/naloxone were examined. Every participant received each test dose under the three buprenorphine maintenance dose conditions.

RESULTS

Intravenous buprenorphine/naloxone was self-administered less frequently than buprenorphine or heroin (P < 0.0005). Participants were most likely to self-administer drug intravenously when maintained on the lowest sublingual buprenorphine dose. Subjective ratings of 'drug liking' and 'desire to take the drug again' were lower for buprenorphine/naloxone than for buprenorphine or heroin (P = 0.0001). Participants reported that they would pay significantly less money for buprenorphine/naloxone than for buprenorphine or heroin (P < 0.05). Seven adverse events were reported; most were mild and transient.

CONCLUSIONS

These data suggest that although the buprenorphine/naloxone combination has intravenous abuse potential, that potential is lower than it is for buprenorphine alone, particularly when participants received higher maintenance doses and lower buprenorphine/naloxone challenge doses. Buprenorphine/naloxone may be a reasonable option for managing the risk for buprenorphine misuse during opioid dependence treatment.

Fast-tracking implementation through trial design: the case of buprenorphine treatment in Victoria

OBJECTIVES

We investigated how a randomised controlled trial (RCT) could be designed to incorporate features known or thought likely to enhance the uptake of the new treatment into clinical practice post-trial.

METHOD AND RESULTS

Between 1999 and 2001, we trialled buprenorphine treatment for heroin dependence in community settings throughout Victoria, using 28 experienced methadone prescribers and 34 pharmacists across 19 sites. In this case study, we describe how we incorporated seven features considered important in treatment uptake: skilled and experienced practitioners, government and policy support, incentives to prescribe the new treatment, specialist support services, clinical guidelines, training programs and patient involvement and information. We also present information showing that uptake of buprenorphine treatment was substantially boosted in Victoria compared with other Australian jurisdictions immediately after the trial in 2001 and that this increase was sustained until at least 2006.

CONCLUSION

While we cannot prove that our trial design was responsible for the increased uptake of buprenorphine treatment in Victoria, we do show that design has been a neglected aspect of clinical trials in terms of enhancing post-trial uptake of the treatment being tested.

IMPLICATIONS

Those interested in closing the 'know-do' gap between research and practice may wish to further explore this very promising lead. Imaginative linking of features known to enhance treatment uptake to pressing research questions may lead to new information on efficacy, as well as getting valuable drugs into the treatment system more rapidly.

Retention rate and substance use in methadone and buprenorphine maintenance therapy and predictors of outcome: results from a randomized study

This was a 6-month, randomized, flexible-dose study comparing the effects of methadone (Meth) and buprenorphine (Bup) on retention rate and substance use in a sample of 140 opioid-dependent, primarily heroin-addicted, patients who had been without opioid substitution therapy in the 4 weeks prior to the study. The major aims were to compare the efficacy of Bup and Meth in a flexible dosing regimen and to identify possible predictors of outcome. There were no major inhomogeneities between treatment groups. All patients also received standardized psychosocial interventions. Mean daily dosages after the induction phase were 44-50 mg for Meth and 9-12 mg for Bup. Results from this study indicate a favourable outcome, with an overall retention rate of 52.1% and no significant differences between treatment groups (55.3% vs. 48.4%). Substance use decreased significantly over time in both groups and was non-significantly lower in the Bup group. Predictors of outcome were length of continuous opioid use and age at onset of opioid use, although these were only significant in the Bup group. Mean dosage and other parameters were not significant predictors of outcome. Overall, the results of this study give further evidence that substitution treatment is a safe and effective treatment for drug dependence. Meth and Bup are equally effective. Duration of continuous opioid use and age at onset were found to have predictive value for negative outcome. The intensity of withdrawal symptoms showed the strongest correlation with drop-out. Future studies are warranted to further address patient profiles and outcome under different substitution regimens.

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.

Exposure to opioid maintenance treatment reduces long-term mortality

AIMS

To (i) examine the predictors of mortality in a randomized study of methadone versus buprenorphine maintenance treatment; (ii) compare the survival experience of the randomized subject groups; and (iii) describe the causes of death.

DESIGN

Ten-year longitudinal follow-up of mortality among participants in a randomized trial of methadone versus buprenorphine maintenance treatment.

SETTING

Recruitment through three clinics for a randomized trial of buprenorphine versus methadone maintenance.

PARTICIPANTS

A total of 405 heroin-dependent (DSM-IV) participants aged 18 years and above who consented to participate in original study.

MEASUREMENTS

Baseline data from original randomized study; dates and causes of death through data linkage with Births, Deaths and Marriages registries; and longitudinal treatment exposure via State health departments. Predictors of mortality examined through survival analysis.

FINDINGS

There was an overall mortality rate of 8.84 deaths per 1000 person-years of follow-up and causes of death were comparable with the literature. Increased exposure to episodes of opioid treatment longer than 7 days reduced the risk of mortality; there was no differential mortality among methadone versus buprenorphine participants. More dependent, heavier users of heroin at baseline had a lower risk of death, and also higher exposure to opioid treatment. Older participants randomized to buprenorphine treatment had significantly improved survival. Aboriginal or Torres Strait Islander participants had a higher risk of death.

CONCLUSIONS

Increased exposure to opioid maintenance treatment reduces the risk of death in opioid-dependent people. There was no differential reduction between buprenorphine and methadone. Previous studies suggesting differential effects may have been affected by biases in patient selection.

Quality of life among heroin users on buprenorphine versus methadone maintenance

OBJECTIVES

To assess the quality of life (QoL) of heroin users starting and following 4 and 8 months of maintenance treatment program using buprenorphine vs. methadone.

METHODS

Participants received maintenance treatment with oral methadone or sublingual buprenorphine for the treatment of heroin dependence. Participants' QoL was measured using the Quality of Life Enjoyment and Satisfaction Questionnaire completed before treatment and at 1-, 4-, and 8-month follow-up. Baseline data from 304 heroin-dependent participants starting maintenance treatment, and 4-month and 8-month follow-up data for the 180 and 129 participants, respectively, retained in trial treatment are presented.

RESULTS

For the participants retained in treatment, statistically significant improvements in QoL and all specific life domains were observed in 4 and 8 months. However, for users who were maintained on methadone, this improvement was observed during the first month of treatment.

CONCLUSIONS

The results show the beneficial effects of the maintenance treatment programs using both buprenorphine and methadone with regard to satisfaction with QoL and all specific life domains among heroin-dependent outpatients, with methadone having an earlier onset than buprenorphine. Further studies are needed to identify the factors linked to these benefits and their time course.

Buprenorphine Use: The International Experience

The confluence of the heroin injection epidemic and the human immunodeficiency virus (HIV) infection epidemic has increased the call for expanded access to effective treatments for both conditions. Buprenorphine and methadone are now listed on the World Health Organization's Model Essential Drugs List. In France, which has the most extensive experience, buprenorphine has been associated with a dramatic decrease in deaths due to overdose, and buprenorphine diversion appears to be associated with inadequate dosage, social vulnerability, and prescriptions from multiple providers. Other treatment models (in the United States, Australia, Germany, and Italy) and buprenorphine use in specific populations are also reviewed in the present article. In countries experiencing a dual epidemic of heroin use and HIV infection, such as former states of the Soviet Union and other eastern European and Asian countries, access to buprenorphine and methadone may be one potential tool for reducing the spread of HIV infection among injection drug users and for better engaging them in medical care.

Follow-up difficulty: correlates and relationship with outcome in heroin dependence treatment in the NEPOD study

Data collected from 317 heroin users who participated in four studies that were included in the Australian National Evaluation of Pharmacotherapies for Opioid Dependence were analysed to examine predictors of follow-up difficulty and whether follow-up difficulty was related to heroin use outcomes. Participants who were no longer receiving treatment were more difficult to contact and more likely to be lost to follow-up. Participants treated in general practice settings were also more difficult to contact and more likely to be lost to follow-up than participants treated at specialist clinics. Contact difficulty among followed-up participants (either in or out of treatment) was unrelated to heroin use outcomes. The 21% of participants who were followed-up with just one contact attempt reported 20.0 heroin-free days in the previous month, increasing only slightly to 20.9 based on the 70% of participants eventually contacted after up to 20 attempts. The study examined three methods for imputing missing heroin use outcome data and concluded that imputation of missing outcome data by inserting corresponding baseline data may be too conservative.

The practice of office-based buprenorphine treatment of opioid dependence: is it associated with new patients entering into treatment?

Office-based buprenorphine holds the promise of bringing patients who have never received pharmacotherapy into treatment. In a cross-sectional and longitudinal analysis, we compared patients entering a clinical trial of buprenorphine in a Primary Care Clinic (PCC) and those entering a local Opioid Treatment Program (OTP) and we compared the clinical characteristics and treatment outcomes of PCC patients with no history of methadone treatment (new-to-treatment) to those with prior methadone treatment. PCC subjects (N=96) were enrolled in a 26-week randomized clinical trial of office-based buprenorphine/naloxone provided in a PCC. OTP subjects (N=94) were enrolled in methadone maintenance during the same time period. PCC subjects compared with OTP subjects were more likely to be male (77% versus 55%, p<0.01), full-time employed (46% versus 15%, p<0.001), have no history of methadone treatment (46% versus 61%, p<0.05), have fewer years of opioid dependence (10 versus 15, p<0.001), and lower rates of injection drug use (IDU) (44% versus 60%, p=0.03). The new-to-treatment PCC subjects were younger (36 years versus 41 years, p=0.001), more likely to be white (77% versus 57%, p=0.04), had fewer years of opioid dependence (7 versus 14, p<0.001), were less likely to have a history of IDU (35% versus 54%, p=0.07), and had lower rates of hepatitis C (25% versus 61%, p=0.002) than subjects with prior methadone treatment. Abstinence and treatment retention were comparable in both groups. The results suggest that office-based treatment of opioid dependence is associated with new types of patients entering into treatment. Treatment outcomes with buprenorphine in a PCC do not vary based on history of prior methadone treatment.

The rise of buprenorphine prescribing in England: analysis of NHS regional data, 2001-03

AIMS

Since its launch in the prescribing market in 1999 for the treatment of opiate dependence, buprenorphine has rapidly become established as an alternative to methadone treatment in the United Kingdom. In the absence of evidence of its clinical superiority over methadone, and given its high relative cost, we sought to examine the impact of buprenorphine availability on opiate treatment services in England.

METHODS

Quarterly buprenorphine and methadone community prescription figures were obtained for 28 Strategic Health Authorities (SHAs) in England, for the 2-year period September 2001 to September 2003. Rates of buprenorphine prescribing (as proportion of all opiate prescriptions) were examined over time by number of prescriptions and net ingredient cost.

RESULTS

Buprenorphine prescription rates increased disproportionately to methadone in all 28 SHAs. By the end of 2003 the number of buprenorphine prescriptions had increased to 23% of all opiate prescriptions, but accounted for 45% of opiate prescription costs in England. Buprenorphine prescribing rates varied substantially across different regions.

CONCLUSIONS

Buprenorphine prescribing has increased dramatically and represents a disproportionately large fraction of community opiate prescribing costs. The marked regional variation suggests the need for further research and the development of national guidelines to support rational prescribing and equitable access to treatment.