A meta-analysis comparing the effectiveness of buprenorphine and methadone

Opiate agonist treatment to improve health of individuals with opioid use disorder in Lebanon

BACKGROUND

Opioid agonist therapy has been widely used to reduce harms among individuals with opioid use disorder but its effectiveness has not been evaluated in the Middle East North African (MENA) region. This study aims to evaluate the effectiveness of a program using opioid agonist therapy in combination with psychosocial support on improving psychological and social well-being, reducing arrest, and reducing risky behavior in individuals with opioid use disorder in Lebanon.

METHODS

A one-group pre-test post-test design study was performed at SKOUN Lebanese Addiction Centre between January 2013 and December 2014. Eighty-six out of 181 patients agreed to participate and completed the 3-month assessment and 38 concluded the 12-month assessment. Psychological (depression and anxiety, quality of life), substance dependence/abuse, behavioral (injecting behavior, sharing needles and paraphernalia), and social outcomes were evaluated at baseline, 3, and 12 months post-treatment.

RESULTS

Remarkable statistical significance improvements were observed 3 months after treatment in most outcome variables including quality of life, anxiety, substance dependence, overdose, employment, and injecting behavior. Improvements were sustained 12 months after treatment.

CONCLUSION

Results support expanding the access to opioid agonist therapy in other MENA countries to treat substance dependence and reduce harms among individuals with opioid use disorder.

Substance Use in Rural Central Appalachia: Current Status and Treatment Considerations

The burden of substance use and especially the unmatched rates of overdoses in rural Central Appalachia highlight the need for innovative approaches to curb the initiation to drug misuse and to address current substance use disorders. Effective substance use interventions involve a thorough understanding of the region. In Central Appalachia, many of the barriers to treatment are shared with other rural and impoverished areas, including a lack of access to health care and lack of health care providers with specialized training. Parts of Appalachia also present their own considerations, including the challenges of fostering trust and encouraging treatment-seeking in communities with dense, long-term, place-based social and family networks. Current policies and interventions for substance use have been largely inadequate in the region, as evidenced by continued increases in substance use and substance-related deaths, especially related to nonmedical prescription drug use and increasing heroin use. The authors discuss ways in which rural life, poverty, identity, and values in Appalachia have influenced substance use and treatment and propose strategies and interventions to improve outcomes.

Medical treatments for opioid use disorder in Iran: a randomized, double-blind placebo-controlled comparison of buprenorphine/naloxone and naltrexone maintenance treatment

AIMS

With the broad goals of developing a clinical research and training program and disseminating effective opioid use disorder treatments in Iran, this pilot clinical trial compared the effectiveness of oral naltrexone (NTX) and sublingual buprenorphine/naloxone (BNX).

DESIGN

Twelve-week single-site, two-group parallel randomized double-blind clinical trial.

SETTING

An out-patient clinical research program in Tehran, Iran.

PARTICIPANTS

Following medically assisted withdrawal, participants with opioid use disorder were assigned randomly to NTX (n = 51) or BNX (n = 51).

INTERVENTION

Medications were administered three times per week, double-blind, double-dummy for 12 weeks. All participants received weekly group drug counseling.

MEASUREMENTS

The primary outcome was initial duration of opioid abstinence verified by urine toxicology tests. Secondary outcomes included the number of opioid-negative urine tests, treatment retention and proportions with sustained, verified opioid-abstinence for 12 weeks.

FINDINGS

Mean [95% confidence interval (CI)] number of days of initial duration of verified abstinence was 28.8 (20.0-37.5) with BNX and 21.6 (14.4-28.7) with NTX (P = 0.205). The mean (95% CI) number of opioid-negative urine tests was 19.7 (17.7-21.6) with BNX and 15.4 (13.1-17.8) with NTX (P = 0.049). The mean (95% CI) number of days in treatment was 70.6 (63.6-77.7) with BNX versus 56.5 (47.8-65.3) with NTX (P = 0.013). The rate of sustained, 12-week opioid abstinence was 16% (8/51) in the BNX group and 8% (4/51) in the NTX group (P = 0.219).

CONCLUSIONS

Among patients with opioid use disorder in Iran, sublingual buprenorphine/naloxone was associated with a greater number of opioid-negative urine tests and treatment retention than oral naltrexone, but not significantly greater initial abstinence duration or proportions with sustained abstinence.

A Perspective on Opioid Pharmacotherapy: Where We Are and How We Got Here

Four decades of concerted pharmacotherapy research has netted us three medications approved for the treatment of opioid addiction. The clinical pharmacology, safety, efficacy, and clinical use of these medications are familiar to most clinical researchers and clinicians in addiction medicine. Less common is an understanding of the social and political forces behind the choice of these particular agents for their development and how these forces continue to influence how clinicians interact with patients who have opioid use disorder. This review brings into focus those forces and puts into context how we came to have these particular medications. What we know determines our views of the world we live in, including our patients and ourselves, as well as those to whom we give power to govern us. The issues are raised by the author, who does not provide resolutions; answers to the questions of how to address the issues must come from the reader.

Clinical Needs of Patients with Problem Drug Use

INTRODUCTION

Illicit drug use is a serious public health problem associated with significant co-occurring medical disorders, mental disorders, and social problems. Yet most individuals with drug use disorders have never been treated, though they often seek medical treatment in primary care. The purpose of this study was to examine the baseline characteristics of people presenting in primary care with a range of problem drug use severity to identify their clinical needs.

METHODS

We examined sociodemographic characteristics, medical and psychiatric comorbidities, drug use severity, social and legal problems, and service utilization for 868 patients with drug problems. These patients were recruited from primary care clinics in a medical safety net setting. Based on Drug Abuse Screening Test results, individuals were categorized as having low, intermediate, or substantial/severe drug use severity.

RESULTS

Patients with substantial/severe drug use severity had serious drug use (opiates, stimulants, sedatives, intravenous drugs); high levels of homelessness (50%), psychiatric comorbidity (69%), and arrests for serious crimes (24%); and frequent use of expensive emergency department and inpatient hospitals. Patients with low drug use severity were primarily users of marijuana, with little reported use of other drugs, less psychiatric comorbidity, and more stable lifestyles. Patients with intermediate drug use severity fell in between the substantial/severe and low drug use severity subgroups on most variables.

CONCLUSIONS

Patients with the highest drug use severity are likely to require specialized psychiatric and substance abuse care, in addition to ongoing medical care that is equipped to address the consequences of severe/substantial drug use, including intravenous drug use. Because of their milder symptoms, patients with low drug use severity may benefit from a collaborative care model that integrates psychiatric and substance abuse care in the primary care setting. Patients with intermediate drug use severity may benefit from selective application of interventions suggested for patients with the highest and lowest drug use severity. Primary care safety net clinics are in a key position to serve patients with problem drug use by developing a range of responses that are locally effective and that may also inform national efforts to establish patient-centered medical homes and to implement the Affordable Care Act.

A retrospective study of retention of opioid-dependent adolescents and young adults in an outpatient buprenorphine/naloxone clinic

OBJECTIVES

Opioid abuse and dependence rates continue to rise among U.S. adolescents. Medication-assisted treatment with buprenorphine/naloxone (BUP/NAL) has been shown to be effective up to 12 weeks. Few data are available regarding extended treatment outcomes. The objective of this study was to describe 1-year retention and compliance of a specific pediatric, outpatient BUP/NAL treatment program for opioid-dependent adolescents and young adults.

METHODS

Retrospective chart review was conducted of all opioid-dependent adolescents and young adults (N = 103) who sought treatment from January 12, 2010, to January 9, 2011. Participants were classified as prescription opioid-dependent or combined heroin/prescription opioid-dependent. Opioid abstinence and BUP/NAL compliance were assessed by urine drug screen (UDS) at each visit. A Kaplan-Meier curve was fit to describe patients' retention time over 1 year.

RESULTS

Mean age was 19.2 ± 1.6 years, 50.5% male, 98.1% white non-Hispanic, and 31.9% prescription opioid-dependent. Overall rates of opioid abstinence and BUP/NAL compliance were high (85.2% and 86.6%, respectively). Seventy-five percent of patients returned for a second visit. Patient retention was 45% at 60 days and 9% at 1 year. Female sex (P < 0.05), negative UDS for opioids (P < 0.001) or tetrahydrocannabinol (P < 0.001), and positive UDS for BUP/NAL (P < 0.001) were associated with longer retention time.

CONCLUSIONS

Although patient retention was the largest barrier to success, a subset of opioid-dependent adolescents and young adults achieved long-term sobriety in our specific clinic program with continued outpatient BUP/NAL therapy. Retention correlated with UDS negative for opioids, negative for tetrahydrocannabinol, and positive for BUP/NAL.

Buprenorphine implant for opioid addiction

SUMMARY The buprenorphine implant (Probuphine™, Titan Pharmaceuticals, CA, USA) is a recently developed long-acting formulation of buprenorphine, which is a partial opioid agonist that is widely used in the marketed, sublingual, daily-dose form for managing opioid addiction. The new formulation uses a novel delivery system consisting of subcutaneously implanted solid matrix 'rods' made from a mixture of ethylene vinyl acetate and buprenorphine. The buprenorphine implant was developed to ensure medication compliance, eliminate misuse and abuse from diversion of sublingual buprenorphine, and increase therapeutic benefit of the medication. The implant is not a 'new' drug, but an innovative means of delivering a medication proven effective for treating opioid addiction. The implant has not yet been approved by the US FDA. The information in this review has been gleaned from research reports, documentation in the literature, and from the author's experience treating opioid-dependent patients, and involvement in clinical research examining sublingual buprenorphine and the buprenorphine implant.

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.

Cingulate biochemistry in heroin users on substitution pharmacotherapy

OBJECTIVE

High doses of opiate substitution pharmacotherapy are associated with greater treatment retention and lower illicit drug consumption, although the neurobiological bases of these benefits are poorly understood. Dysfunction of the anterior cingulate cortex (ACC) is associated with greater addiction severity and mood dysregulation in opiate users, such that the beneficial effects of substitution pharmacotherapy may relate to normalisation of ACC function. This study aimed to investigate the differential impact of methadone compared with buprenorphine on dorsal ACC biochemistry. A secondary aim was to explore the differential effects of methadone and buprenorphine on dorsal ACC biochemistry in relation to depressive symptoms.

METHODS

Twenty-four heroin-dependent individuals stabilised on methadone (n=10) or buprenorphine (n=14) and 24 healthy controls were scanned using proton Magnetic Resonance Spectroscopy and compared for metabolite concentrations of N-acetylaspartate, glutamate/glutamine, and myo-inositol.

RESULTS

(1) Methadone was associated with normalisation of dorsal ACC biochemistry (increased N-acetylaspartate and glutamate/glutamine levels, and decreased myo-inositol levels) in a dose-dependent manner; (2) buprenorphine-treated individuals had higher myo-inositol and glutamate/glutamine levels than methadone-treated patients in the right dorsal ACC; and (3) myo-inositol levels were positively correlated with depressive symptoms in participants stabilised on buprenorphine.

CONCLUSIONS

These findings point to a beneficial role of high-dose methadone on dorsal ACC biochemistry, and suggest a link between elevated myo-inositol levels and depressive symptoms in the context of buprenorphine treatment.

Pharmacokinetics of buprenorphine: a comparison of sublingual tablet versus liquid after chronic dosing

Although buprenorphine is approved for use in the outpatient treatment of opioid addiction in 2 tablet formulations, a monoproduct containing buprenorphine only (Subutex) and a buprenorphine/naloxone combination product (Suboxone), much of the clinical data that support the approval by the U.S. Food and Drug Administration were generated by using a sublingual liquid. To interpret the literature in prescribing parameters for tablet buprenorphine, this study was designed to determine steady state buprenorphine plasma levels for the 2 formulations and to assess the relative bioavailability of each. A randomized, double-blind, crossover study with dose increases was conducted during a 12-week period at an outpatient treatment clinic. Of the 184 subjects initially randomized to treatment, 133 (72.3%) were evaluated for the steady-state trough plasma concentration, 16 (8.7%) for relative bioavailability, and 31 (16.8%) for dose proportionality. At steady state, differences in the trough plasma concentrations of buprenorphine between the 2 formulations were found across all the dose levels. Average plasma concentration (Cavg) of the tablet at twice the milligram dose of the liquid was twice that of the liquid; intersubject variability was greater for the tablet. At double the dose of tablet, there is no difference in steady state plasma concentrations. The bioavailability seems equivalent for the 2 formulations across all the dose levels.

The World Federation of Societies of Biological Psychiatry (WFSBP) guidelines for the biological treatment of substance use and related disorders. Part 2: Opioid dependence

OBJECTIVES

To develop evidence-based practice guidelines for the pharmacological treatment of opioid abuse and dependence.

METHODS

An international task force of the World Federation of Societies of Biological Psychiatry (WFSBP) developed these practice guidelines after a systematic review of the available evidence pertaining to the treatment of opioid dependence. On the basis of the evidence, the Task Force reached a consensus on practice recommendations, which are intended to be clinically and scientifically meaningful for physicians who treat adults with opioid dependence. The data used to develop these guidelines were extracted primarily from national treatment guidelines for opioid use disorders, as well as from meta-analyses, reviews, and publications of randomized clinical trials on the efficacy of pharmacological and other biological treatments for these disorders. Publications were identified by searching the MEDLINE database and the Cochrane Library. The literature was evaluated with respect to the strength of evidence for efficacy, which was categorized into one of six levels (A-F).

RESULTS

There is an excellent evidence base supporting the efficacy of methadone and buprenorphine or the combination of buprenorphine and naloxone for the treatment of opioid withdrawal, with clonidine and lofexidine as secondary or adjunctive medications. Opioid maintenance with methadone and buprenorphine is the best-studied and most effective treatment for opioid dependence, with heroin and naltrexone as second-line medications.

CONCLUSIONS

There is enough high quality data to formulate evidence-based guidelines for the treatment of opioid abuse and dependence. This task force report provides evidence for the efficacy of a number of medications to treat opioid abuse and dependence, particularly the opioid agonists methadone or buprenorphine. These medications have great relevance for clinical practice.

Buprenorphine-based regimens and methadone for the medical management of opioid dependence: selecting the appropriate drug for treatment

Maintenance therapy with methadone or buprenorphine-based regimens reduces opioid dependence and associated harms. The perception that methadone is more effective than buprenorphine for maintenance treatment has been based on low buprenorphine doses and excessively slow induction regimens used in early buprenorphine trials. Subsequent studies show that the efficacy of buprenorphine sublingual tablet (Subutex®) or buprenorphine/naloxone sublingual tablet (Suboxone®) is equivalent to that of methadone when sufficient buprenorphine doses, rapid induction, and flexible dosing are used. Although methadone remains an essential maintenance therapy option, buprenorphine-based regimens increase access to care and provide safer, more appropriate treatment than methadone for some patients.

Feasability and safety of transfer from racemic methadone to (R)-methadone in primary care: clinical results from an open study

Methadone is a proven first-line treatment in opioid dependence but few studies have addressed the efficacy of different isoforms of methadone or the transfer from one form to the other. This was a 4-week open study to examine the feasibility and safety of transfer from racemic methadone to (R)-methadone in primary care patients. A total of 1552 opioid-dependent patients formerly treated with racemic methadone were included and followed for 4 weeks after transfer to (R)-methadone. There were few drop-outs, and 1426 patients (91.9%) completed the 4-week transfer period. There were few adverse events or side effects and no deaths occurred during treatment. The number of drug-positive urine screens decreased from 61.2 to 39.8%. Withdrawal symptoms, craving and compliance improved significantly after transfer to (R)-methadone. We conclude that transfer from racemic to (R)-methadone is a safe and practical procedure.

Opioid dependence treatment: options in pharmacotherapy

The development of effective treatments for opioid dependence is of great importance given the devastating consequences of the disease. Pharmacotherapies for opioid addiction include opioid agonists, partial agonists, opioid antagonists, and alpha-2-adrenergic agonists, which are targeted toward either detoxification or long-term agonist maintenance. Agonist maintenance therapy is currently the recommended treatment for opioid dependence due to its superior outcomes relative to detoxification. Detoxification protocols have limited long-term efficacy, and patient discomfort remains a significant therapy challenge. Buprenorphine's effectiveness relative to methadone remains a controversy and may be most appropriate for patients in need of low doses of agonist treatment. Buprenorphine appears superior to alpha-2 agonists, however, and office-based treatment with buprenorphine in the USA is gaining support. Studies of sustained-release formulations of naltrexone suggest improved effectiveness for retention and sustained abstinence; however, randomized clinical trials are needed.

Buprenorphine is a weak partial agonist that inhibits opioid receptor desensitization

Buprenorphine is a weak partial agonist at mu-opioid receptors that is used for treatment of pain and addiction. Intracellular and whole-cell recordings were made from locus ceruleus neurons in rat brain slices to characterize the actions of buprenorphine. Acute application of buprenorphine caused a hyperpolarization that was prevented by previous treatment of slices with the irreversible opioid antagonist beta-chlornaltrexamine (beta-CNA) but was not reversed by a saturating concentration of naloxone. As expected for a partial agonist, subsaturating concentrations of buprenorphine decreased the [Met](5)enkephalin (ME)-induced hyperpolarization or outward current. When the ME-induced current was decreased below a critical value, desensitization and internalization of mu-opioid receptors was eliminated. The inhibition of desensitization by buprenorphine was not the result of previous desensitization, slow dissociation from the receptor, or elimination of receptor reserve. Treatment of slices with subsaturating concentrations of etorphine, methadone, oxymorphone, or beta-CNA also reduced the current induced by ME but did not block ME-induced desensitization. Treatment of animals with buprenorphine for 1 week resulted in the inhibition of the current induced by ME and a block of desensitization that was not different from the acute application of buprenorphine to brain slices. These observations show the unique characteristics of buprenorphine and further demonstrate the range of agonist-selective actions that are possible through G-protein-coupled receptors.

The impact of community pharmacy dispensing fees on the introduction of buprenorphine-naloxone in Australia

INTRODUCTION AND AIMS

The introduction of buprenorphine - naloxone in Australia in April 2006 has permitted the revision of takeaway policies in many states and has introduced the possibility of unsupervised treatment. This study explored the implications of the introduction of buprenorphine - naloxone in terms of cost to patients through a survey of pharmacists' intended pricing practices. The aim of the research was to examine the intentions of pharmacists in relation to fees for buprenorphine - naloxone and study the potential implications to patients when compared with the existing fee structure for methadone and for buprenorphine alone.

DESIGN AND METHODS

A self-complete questionnaire was mailed to every community pharmacy in New South Wales (NSW) (n = 593) dispensing methadone or buprenorphine to people with opioid dependence. A response rate of 68.6% (n = 407) was achieved after three mailouts.

RESULTS

The majority of pharmacies charged a flat weekly fee for methadone (92.2%; mean = $31.90) and buprenorphine (74.8%; mean = $31.00). The mean intended fees for buprenorphine - naloxone according to different dosing and takeaway regimens ranged from $19.19 per week for no supervised doses and fortnightly takeaways to a $30.88 per week flat fee. There appeared to be little variation in fee structure irrespective of the takeaway regimen, until reaching the 2 weeks' unsupervised dose regimen.

DISCUSSION AND CONCLUSIONS

This study highlights the importance of the early dissemination of unambiguous information regarding the introduction of a new medication, especially where supervised dispensing through community pharmacies is essential to the provision of treatment. The potential impact upon the successful rollout of a new treatment paradigm that was developed to benefit stable patients in the community may be jeopardised when such processes are not followed.

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.

The effects of maternally administered methadone, buprenorphine and naltrexone on offspring: review of human and animal data

Most women using heroin are of reproductive age with major risks for their infants. We review clinical and experimental data on fetal, neonatal and postnatal complications associated with methadone, the current "gold standard", and compare these with more recent, but limited, data on developmental effects of buprenorphine, and naltrexone. Methadone is a micro-opioid receptor agonist and is commonly recommended for treatment of opioid dependence during pregnancy. However, it has undesired outcomes including neonatal abstinence syndrome (NAS). Animal studies also indicate detrimental effects on growth, behaviour, neuroanatomy and biochemistry, and increased perinatal mortality. Buprenorphine is a partial micro-opioid receptor agonist and a kappa-opioid receptor antagonist. Clinical observations suggest that buprenorphine during pregnancy is similar to methadone on developmental measures but is potentially superior in reducing the incidence and prognosis of NAS. However, small animal studies demonstrate that low doses of buprenorphine during pregnancy and lactation lead to changes in offspring behaviour, neuroanatomy and biochemistry. Naltrexone is a non-selective opioid receptor antagonist. Although data are limited, humans treated with oral or sustained-release implantable naltrexone suggest outcomes potentially superior to those with methadone or buprenorphine. However, animal studies using oral or injectable naltrexone have shown developmental changes following exposure during pregnancy and lactation, raising concerns about its use in humans. Animal studies using chronic exposure, equivalent to clinical depot formulations, are required to evaluate safety. While each treatment is likely to have maternal advantages and disadvantages, studies are urgently required to determine which is optimal for offspring in the short and long term.

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.

Substance use and quality of life over 12 months among buprenorphine maintenance-treated and methadone maintenance-treated heroin-addicted patients

The purpose of this study was to investigate the effects of methadone treatment and buprenorphine treatment on retention in treatment, urine drug testing results, psychiatric status, social adjustment, and quality of life among patients involved in long-term treatment with the cited medications. Two hundred thirteen patients (106 on buprenorphine treatment and 107 on methadone treatment) were enrolled in this open study at the 3rd month of their treatment and followed up until the 12th month; those who left the program before the end of the 3rd month of their treatment were not included in the study sample. The results of this study show statistically significant improvements in opioid use, psychiatric status, and quality of life between the 3rd and 12th months for both medications. This study suggests the long-term efficacy of methadone treatment and buprenorphine treatment on symptoms of opioid addiction and quality of life.

Buprenorphine-containing treatments: place in the management of opioid addiction

Although the synthetic opioid buprenorphine has been available clinically for almost 30 years, its use has only recently become much more widespread for the treatment of opioid addiction. The pharmacodynamic and pharmacokinetic profiles of buprenorphine make it unique in the armamentarium of drugs for the treatment of opioid addiction. Buprenorphine has partial mu-opioid receptor agonist activity and is a kappa-opioid receptor antagonist; hence, it can substitute for other micro-opioid receptor agonists, yet is less apt to produce overdose reactions or dysphoria. On the other hand, buprenorphine can block the effects of opioids such as heroin (diamorphine) and morphine, and can even precipitate withdrawal in individuals physically dependent upon these drugs. Buprenorphine has significant sublingual bioavailability and a long half-life, making administration on a less than daily basis possible. Furthermore, its discontinuation is associated with only a mild withdrawal syndrome. Clinical trials have demonstrated that sublingual buprenorphine is effective in both maintenance therapy and detoxification of individuals addicted to opioids. The introduction of a sublingual formulation combining naloxone with buprenorphine further reduces the risk of diversion to illicit intravenous use. Because of its relative safety and lower risk of illegal diversion, buprenorphine has been made available in several countries for treating opioid addiction in the private office setting, greatly enhancing treatment options for this condition.

Multimodal drug addiction treatment: A field comparison of methadone and buprenorphine among heroin- and cocaine-dependent patients

AIMS

Our objective was to compare the effectiveness of buprenorphine (BUP) and methadone maintenance treatment in opiate-addicted patients in a clinical nonexperimental setting.

DESIGN

We used a naturalistic observational prospective study of 24 months' duration.

SETTING

Subjects were enrolled and treated at a drug addiction outpatient clinic of the National Health System Local Unit in Milan, Italy.

PARTICIPANTS

Two hundred fifty-seven subjects meeting the DSM-IV criteria for opioid dependence and opioid-seeking substitutive pharmacological treatment participated in the study.

INTERVENTION

One hundred twenty-one subjects received BUP at a mean daily dose of 11 +/- 6 mg (median = 8; range = 2-30) for a mean duration of 249 days. One hundred thirty-six subjects received methadone at a mean daily dose of 54 +/- 29 mg (median = 50; range = 4-140) for a mean duration of 267 days.

MEASUREMENTS

The main efficacy parameters were treatment retention rates and illicit substance abuse, as assessed by urinalysis.

FINDINGS

Retention rates were comparable in both treatment groups, but BUP-treated subjects had significantly lower rates of illicit opiate consumption (p < .0001).

CONCLUSIONS

The results confirm that, in a nonexperimental clinical practice setting, BUP is as effective as methadone in the treatment of heroin dependence, with significantly better opiate abuse control, thus possibly allowing longer and more effective treatment programs with reduced relapse rates.

Pharmacokinetics, bioavailability and opioid effects of liquid versus tablet buprenorphine

AIMS

Two tablet formulations of buprenorphine (a buprenorphine mono-product, Subutex, and a buprenorphine/naloxone combination product, Suboxone) are available for use in the treatment of opioid addiction; however, the bulk of the clinical studies supporting its approval by the US Food and Drug Administration (FDA) were conducted with a sublingual liquid preparation. To assist the clinician in interpreting the relevant literature in establishing dosing parameters for prescription of tablet buprenorphine, this study was designed to compare the steady state: (1) pharmacokinetics and bioavailability, and (2) physiological, subjective and objective opiate effects of two 8 mg buprenorphine tablets (16 mg) to those of 1 ml (8 mg/ml) buprenorphine solution based upon early reports suggesting that the bioavailability of the tablet was approximately 50% of that of the liquid.

DESIGN

Randomized, open-label, two-way crossover study.

SETTING

Inpatient hospitalization for 21 days.

PARTICIPANTS

Twenty-four male and females in general good health and meeting DSM-IV criteria for opiate dependence.

INTERVENTION

Subjects received one of the two buprenorphine formulations in the first 10-day period, and the other for the second 10-day period with no washout.

MEASUREMENTS

Pharmacokinetic analyses, opiate effects and adverse events.

FINDINGS

Drug steady state was reached by Day 7 of each 10-day period, area under the curve for 16 mg (two 8 mg) tablets was higher than the solution. The only non-kinetic statistically significant difference observed between the formulations was in changes in total opioid agonist score.

CONCLUSIONS

The serum concentration achieved by 16 mg of tablet buprenorphine is higher than that of the 8 mg solution, although differences between physiologic, subjective and objective opioid effects were not noted. The relative bioavailability of tablet versus solution is estimated to be 0.71; thus, with respect to dosing parameters for the tablet, clinicians should consider using less than 16 mg to achieve bioequivalence to the 8 mg solution.

Opioid addicts at admission vs. slow-release oral morphine, methadone, and sublingual buprenorphine maintenance treatment participants

With use of a randomized study design, quality of life (QOL) and physical symptoms of opioid addicts at admission were compared with slow-release oral morphine, methadone, and sublingual buprenorphine maintenance program participants after 6 months of treatment. The study was conducted from February to July 2004 in the outpatient drug user treatment center at University Department of Psychiatry at Innsbruck, providing maintenance treatment programs and detoxification in Tyrol, Austria. One hundred twenty opioid users seeking treatment were compared with 120 opioid-dependent patients retained for 6 months on a slow-release oral morphine, methadone, or sublingual buprenorphine maintenance program. The German version ("Berlin Quality of Life Profile") of the Lancashire Quality of Life Profile was used, and illicit opioid use was determined by urinalysis. Physical symptoms were measured by using the Opioid Withdrawal Scale. Urinalyses revealed a significantly lower consumption of cocaine and opioids in all three substitution groups than in patients at admission (p < 0.001 and p < or = 0.004, respectively). Both the buprenorphine and the methadone maintenance group showed significantly more favorable values than opioid clients at admission for stomach cramps (p < or = 0.002), muscular tension (p < or = 0.027), general pain (p < or = 0.001), feelings of coldness (p < or = 0.000), heart pounding (p < or = 0.008), runny eyes (p < or = 0.047), and aggressions (p < or = 0.009). Patients who received slow-release oral morphine treatment generally showed the least favorable QOL scores compared with patients at admission or sublingual buprenorphine and methadone clients. Patients in the sublingual buprenorphine or methadone program showed nearly the same QOL scores. The buprenorphine and the methadone maintenance group showed significantly more favorable values than opioid clients at admission regarding leisure time (p < or = 0.019), finances (p < or = 0.014), mental health (p < or = 0.010), and overall satisfaction (p < or = 0.010). Slow-release oral morphine is a well-established treatment for pain, but more research is required to evaluate it as a treatment for heroin dependence. The present data indicate that slow-release oral morphine could have some disadvantages compared with sublingual buprenorphine and methadone in QOL, physical symptoms, and additional consumption. The results further suggest that buprenorphine treatment is as effective as methadone in effects on quality of life and physical symptoms.

The effect of buprenorphine and benzodiazepines on respiration in the rat

Methadone and buprenorphine are the two main opioid substitution treatments for heroin dependence currently offered in Australia. A number of publications have implicated buprenorphine as being potentially dangerous in combination with benzodiazepines but no comparison has been made to the relative dangers of benzodiazepines combined with buprenorphine or methadone. The effect of i.v. methadone and buprenorphine on respiration was investigated by evaluating arterial blood pCO2, pO2 and pH, and measuring respiratory rate in rats. Measurements were taken at 0, 15, 30, 60, 120, 180 and 240 min after i.v. administration of methadone or buprenorphine. Effects on respiration were greatest 15 min after i.v. drug administration. The effect of methadone and buprenorphine on respiration was compared with and without diazepam pretreatment (20 mg/kg). Buprenorphine alone exhibited a bell shaped dose response inhibition of respiration; however the plateau of the dose response inhibition on respiration was lost when administered in combination with diazepam. Methadone showed a dose-dependent inhibitory effect on respiration, which was potentiated with diazepam pretreatment. While the effect of diazepam pretreatment was the abolishment of the protective bell shaped dose response effect on respiration, the effect of buprenorphine and diazepam was not greater than methadone and diazepam.

Induction of patients with moderately severe methadone dependence onto buprenorphine

Current clinical practice allows patients with low levels of physiological dependence on opioids (equivalent to methadone doses of 30 mg/d or less) to be transferred to buprenorphine. This study investigated the response of opioid-dependent patients receiving doses of methadone between 30-70 mg/d when transferred to buprenorphine at doses between 12-16 mg/d. Twenty-three patients receiving inpatient opioid detoxification agreed to take part in a trial of facilitated transfer to buprenorphine. Following the last morning dose of methadone, buprenorphine was substituted in doses increasing from 4 mg to a maximum of 16 mg, with adjunctive lofexidine (maximum of 2.4 mg/d). All except two patients successfully completed transfer to buprenorphine. To investigate the effect of initial methadone dose, the group was split into intermediate dose (ID; 30 - 49 mg/d; n = 10) and high dose (HD; 50-70 mg/d; n = 11) groups. Average stabilisation dose of buprenorphine for the sample who completed transfer was 14.0 mg/d (SD 2.3) and average daily lofexidine dose during transfer was 0.57 mg (SD 0.39). The HD group used significantly more lofexidine to complete transfer compared to the ID group. Increased opioid withdrawal symptoms, of mild severity as measured by the Short Opiate Withdrawal Scale (SOWS), were found in the HD group compared with the ID group during the first and last day of buprenorphine stabilisation. However, average SOWS scores for the whole of the period of transfer were not significantly different from those during the period of stabilisation on buprenorphine in either the ID or HD groups. This study suggests that transfer to buprenorphine is relatively uncomplicated from daily methadone doses of 30-70 mg in an inpatient setting and may be facilitated by use of lofexidine. This procedure may allow a larger proportion of opioid-dependent patients access to buprenorphine treatment.

Cross-reactivity of the CEDIA buprenorphine assay with opiates: an Austrian phenomenon?

When testing the Microgenics CEDIA assay for immunological buprenorphine analysis, cross-reactivity between the buprenorphine reagents and opiates was observed at concentrations higher than 120 mg/l morphine, 320 mg/l methadone, 30 mg/l codeine, 60 mg/l dihydrocodeine and 520 mg/l morphine-3-glucuronide. The cross-reactivity with morphine has the greatest impact on routine screening as opiate maintenance therapy in Austria is also performed with slow-release oral morphine. The use of a second cutoff value of 30 mug/l for urine samples that are (immunologically) positive for opiates is therefore suggested, compared to the cutoff value of 5 microg/l proposed by the manufacturer.

The clinical use of buprenorphine in opiate addiction: evidence and practice

Buprenorphine is a partial μ-opioid receptor agonist that is being increasingly used in clinical practice in the treatment of opioid dependence in the UK, USA, and, elsewhere. Its unique pharmacological properties mean it is a relatively safe drug, it can be given by alternate day dispensing, and it is associated with relatively mild symptoms on withdrawal. The interpretation of the research literature on buprenorphine is however, complex, and often appears to be in conflict with how buprenorphine is used in clinical practice. This article describes these apparent contradictions, their likely explanations, and how these may further inform our clinical practice. The article also describes the clinically relevant pharmacological properties of buprenorphine, compares it to methadone, relates the evidence to clinical experience, and provides practical advice on how to manage the most common clinical techniques. The best quality evidence suggests that very rapid buprenorphine induction is not associated with a higher drop-out rate than methadone, that buprenorphine is probably as good as methadone for maintenance treatment, and is superior to methadone and α-2 adrenergic agonists for detoxification. However, buprenorphine cannot yet be considered the 'gold standard' treatment for opiate dependence because of the higher drop-out rates that may occur on induction using current techniques, its high-cost relative to methadone, and because the place of buprenorphine in treatment is still continuing to evolve.

Buprenorphine blocks withdrawal in morphine-dependent rat pups

BACKGROUND

Infants placed on extracorporeal membrane oxygenation (ECMO) or mechanical ventilation often need continuous morphine infusions for pain relief and sedation. The resulting physical dependence requires an additional 2-3-week hospital stay to taper the morphine to avoid withdrawal. Buprenorphine effectively blocks abstinence in dependent adults, and in infants it could accelerate or eliminate the tapering schedule, thereby enabling earlier hospital dismissals.

METHODS

Morphine-dependent infant rats were used in this study to determine the effectiveness of buprenorphine in blocking abstinence. Postnatal day-14 (P14) rats were implanted with osmotic minipumps that delivered saline (1 microl x h(-1)) or morphine (2 mg x kg(-1) h(-1)) for 72 h. The minipumps were then removed to allow the rats to undergo spontaneous morphine withdrawal.

RESULTS

The withdrawal period lasted approximately 72 h out of a 96-h observation period. The following signs were significant during these hours: wet-dog shakes, 1-72 h; abdominal stretches, 1-72 h; forepaw tremors, 1-24 h; splayed hind-limbs, 1-72 h; ptosis, 4-72 h; and evoked vocalization, 4 and 8 h. A single 1 mg x kg(-1) buprenorphine dose significantly decreased wet-dog shakes from 1 to 72 h, abdominal stretches from 1 to 48 h, forepaw tremors and splayed hind-limbs 1-8 h, and ptosis and evoked vocalization at 4 and 8 h. Repeated administration of 1 mg x kg(-1) buprenorphine before pump removal and at 24, 48 and 72 h resulted in a greater magnitude of blockade of abstinence throughout the 96-h observation period.

CONCLUSIONS

Buprenorphine may prove to be a suitable drug for treating opioid withdrawal in human infants.

Differential effects of gestational buprenorphine, naloxone, and methadone on mesolimbic mu opioid and ORL1 receptor G protein coupling

In addition to its use for heroin addiction pharmacotherapy in general, buprenorphine has advantages in treating maternal heroin abuse. To examine the gestational effects of buprenorphine on opioid receptor signaling, the [(35)S]-GTP gamma S in situ binding induced by the mu agonist [D-Ala(2),MePhe(4),Gly(5)-ol] enkephalin (DAMGO) or the nociceptin/orphanin FQ (N/OFQ) agonist was measured in mesolimbic structures of pup brains from pregnant rats administered with buprenorphine +/- naloxone, naloxone, or methadone by osmotic minipump. Drug- and gender-based changes in DAMGO- and N/OFQ-induced GTP gamma S binding were discovered in mesolimbic regions of dam, P2, and P7 brains. Buprenorphine and/or methadone gestational treatment attenuated DAMGO-induced GTP gamma S binding in some dam and male P2 mesolimbic regions. Methadone diminished DAMGO-induced GTP gamma S binding in almost all monitored brain regions of the dam but had few effects on their N/OFQ-induced GTP gamma S binding. Naloxone used in combination with buprenorphine blocked the inhibition by buprenorphine alone on DAMGO-induced GTP gamma S binding. In contrast to its inhibitory effects on DAMGO-induced GTP gamma S binding, buprenorphine stimulated N/OFQ-induced GTP gamma S binding in male P2 nucleus accumbens and lateral septum. Brain region-dependent gender differences in DAMGO-induced GTP gamma S binding were seen in P2 pups, and males showed greater sensitivity to buprenorphine and methadone than females. Our findings on mu opioid receptor (MOR) GTP-binding regulatory protein (G protein) coupling and its gender dependency are consistent with our earlier studies on mu receptor binding adaptation induced by buprenorphine in dams and neonatal rats after in utero treatment regimens, and they extend the gestational effects of this opiate to mu and N/OFQ receptor functionality.

Short-term buprenorphine maintenance: treatment outcome

Fifty-two heroin addicts were inducted onto buprenorphine under the care of psychiatric residents in a setting modeled on office practice. Subjects were maintained on a protocol of six weeks of 16 mg daily dosing, then tapered to zero dose up to week 16, and maintained on placebo through week 18. Of 44 subjects who continued after the first induction dose, 11 terminated during maintenance, 17 during taper; and 16 while on zero dose. Twice weekly urine toxicologies showed significant successive declines in samples positive for heroin use across these three periods: 70%, 41%, and 20%, respectively. Among historical variables, only prior AA attendance distinguished subjects who achieved zero dose from those who did not. A comparison with recent studies suggests that relatively inexperienced office-based physicians can maintain patients on buprenorphine at a level comparable to that reported for research clinic settings, but with comparable rates of heroin abstinence. These findings are discussed in light of potential options for office-based opioid maintenance.

Buprenorphine maintenance versus placebo or methadone maintenance for opioid dependence

BACKGROUND

Buprenorphine has recently been reported to be an alternative to methadone and LAAM for maintenance treatment of opioid dependent individuals, 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 2001, inclusive: Cochrane Drugs and Alcohol Review Group Register, the Cochrane Controlled Trials Register, MEDLINE, EMBASE, Current Contents, Psychlit, CORK [www. state.vt.su/adap/cork], Alcohol and Drug Council of Australia (ADCA) [www.adca.org.au], Australian Drug Foundation (ADF -VIC) [www.adf.org.au], Centre for Education and Information on Drugs and Alcohol (CEIDA) [www.ceida.net.au], Australian Bibliographic Network (ABN), and Library of Congress databases, available NIDA monographs and the College on Problems of Drug Dependence Inc. proceedings, the reference lists of all identified studies and published reviews and authors of identified RCT's were asked about any other published or unpublished relevant RCT.

SELECTION CRITERIA

Randomised clinical trials of buprenorphine maintenance compared with either placebo or methadone maintenance for opioid dependence.

DATA COLLECTION AND ANALYSIS

Reviewers evaluated the papers separately and independently, rating methodological quality of concealment of allocation; data were extracted independently for meta-analysis and double-entered.

MAIN RESULTS

Thirteen studies met the inclusion criteria, all were randomised clinical trials, all but one were double-blind. The method of concealment of allocation was not clearly described in 11 of the studies, otherwise methodological quality was good. Buprenorphine given in flexible doses appeared statistically significantly less effective than methadone in retaining patient in treatment (RR= 0.82; 95% CI: 0.69-0.96). Low dose buprenorphine is not superior to low dose methadone. High dose buprenorphine does not retain more patients than low dose methadone, but may suppress heroin use better. There was no advantage for high dose buprenorphine over high dose methadone in retention (RR=0.79; 95% CI:0.62-1.01), and high dose buprenorphine was inferior in suppression of heroin use. Buprenorphine was statistically significantly superior to placebo medication in retention of patients in treatment at low doses (RR=1.24; 95% CI: 1.06-1.45), high doses (RR=1.21; 95% CI: 1.02-1.44), and very high doses (RR=1.52; 95% CI: 1.23-1.88). However, only high and very high dose buprenorphine suppressed heroin use significantly above placebo.

REVIEWERS' CONCLUSIONS

Buprenorphine is an effective intervention for use in the maintenance treatment of heroin dependence, but it is not more effective than methadone at adequate dosages.

Opiate maintenance with buprenorphine in ambulatory care: a 24-week follow-up study of new users

BACKGROUND

Many studies suggest that buprenorphine, a long acting partial opioid agonist, may be comparable to methadone in efficacy, with fewer withdrawal symptoms and a lower risk of overdose. The aim of this study was to assess the patterns of buprenorphine prescription use in ambulatory care and retention rate under treatment during a 24-week follow-up period.

METHODS

This observational cohort study included buprenorphine users identified from the French Health System prescription database in an area of 1 million inhabitants and followed for 24 weeks.

RESULTS

We selected 282 users of buprenorphine defined as "new users" (74% male, mean age 32.4+/-6.2 years). Three groups were defined: 50% of "rational users" (141 subjects, no more than 2 prescribers), 24% of "occasional users" (67 subjects, less than 2 buprenorphine prescriptions) and 26% of "non-rational users" (74 subjects, 3 or more prescribers). The overall 24-week treatment retention rate was 37%. Misuse of buprenorphine or benzodiazepines was significantly more frequent in "non-rational" than "rational users".

CONCLUSION

The retention rate with buprenorphine estimated in this observational study was very similar to that obtained in controlled trials. A majority of regular users of buprenorphine could be regarded as "rational users" in this area of France.

Evaluation of buprenorphine maintenance treatment in a French cohort of HIV-infected injecting drug users

BACKGROUND

Buprenorphine was approved in France for treating opiate dependence in July 1995 and can be prescribed by general practitioners (GPs). Most studies assessing buprenorphine maintenance treatment (BMT) outcomes have taken place in GP settings. An evaluation of BMT outcomes in patients already followed for their HIV-infection could supply additional information about the changes in addictive practices in a non-GP setting.

METHODS

We assessed BMT discontinuations and the course of self-reported addictive behaviours and characteristics associated with buprenorphine-injection misuse in 114 HIV-infected patients on BMT who were followed in a hospital-based outpatient department.

RESULTS

The continuous series of follow-up visits at which these 114 patients reported regular buprenorphine prescriptions accounted for 237.5 person-years of observation, i.e. 475 follow-up visits. Of the 114 patients on BMT, 43% continued BMT throughout the follow-up, 40% stopped it, and results for 17% were not available either because they did not answer the self-administered questionnaire (5%) or because they were lost to follow-up (12%). Addictive behaviours declined but buprenorphine injection misuse remained stable. Depression measured by the CESD score (RR=1.04 95%CI [1.01-1.06]), cocaine use (RR=2.48 95%CI [1.31-4.68]) and alcohol consumption exceeding 4 alcohol units (AU) per day (RR=2.29, 95%CI [1.17-4.46]) were independently associated with buprenorphine injection misuse among stabilised BMT patients.

CONCLUSIONS

Despite the reduction in drug injection after starting BMT, buprenorphine injection misuse mainly involves patients with characteristics of severe addiction. Better monitoring of the illicit drug use patterns of patients on BMT may suggest new medical strategies for GPs to improve BMT outcomes.

A comparison of buprenorphine treatment in clinic and primary care settings: a randomised trial

OBJECTIVE

To compare outcomes, costs and incremental cost-effectiveness of heroin detoxification performed in a specialist clinic and in general practice.

DESIGN AND SETTING

Randomised controlled trial set in a specialist outpatient drug treatment centre and six office-based general practices in inner city Sydney, Australia.

PARTICIPANTS

115 people seeking treatment for heroin dependence, of whom 97 (84%) were reinterviewed at Day 8, and 78 (68%) at Day 91.

INTERVENTIONS

Participants were randomly allocated to primary care or a specialist clinic, and received buprenorphine for 5 days for detoxification, then were offered either maintenance therapy with methadone or buprenorphine, relapse prevention with naltrexone, or counselling alone.

MAIN OUTCOME MEASURES

Completion of detoxification, engagement in post-detoxification treatment, and heroin use assessed at Days 8 and 91. Costs relevant to providing treatment, including staff time, medication use and diagnostic procedures, with abstinence from heroin use on Day 8 as the primary outcome measure.

RESULTS

There were no significant differences in the proportions completing detoxification (40/56 [71%] primary care v 46/59 [78%] clinic), participating in postwithdrawal treatment (28/56 [50%] primary care v 36/59 [61%] clinic), reporting no opiate use during the withdrawal period (13/56 [23%] primary care v 13/59 [22%] clinic), and in duration of postwithdrawal treatment by survival analysis. Most participants in both groups entered postwithdrawal buprenorphine maintenance. On an intention-to-treat basis, self-reported heroin use in the month before the Day 91 interview was significantly lower than at baseline (27 days/month at baseline, 14 days/month at Day 91; P < 0.001) and did not differ between groups. Buprenorphine detoxification in primary care was estimated to be $24 more expensive per patient than treatment at the clinic. The incremental cost-effectiveness ratio reveals that, in this context, it costs $20 to achieve a 1% improvement in outcome in primary care.

CONCLUSIONS

Buprenorphine-assisted detoxification from heroin in specialist clinic and primary care settings had similar efficacy and cost-effectiveness. Buprenorphine treatment can be initiated safely in primary care settings by trained GPs.

Buprenorphine versus methadone maintenance treatment in an ambulant setting: a health-related quality of life assessment

BACKGROUND

To compare the effects on quality of life (QOL) of oral methadone with sublingual buprenorphine.

METHODS

We performed an open-label, non-randomized, two-site (methadone-buprenorphine) study. During 6 months we assessed the quality of life status of 53 opioid-dependent patients admitted to a methadone or buprenorphine maintenance programme using the German version (Berlin Quality of Life Profile) of the Lancashire Quality of Life Profile. Physical symptoms were measured using the Opioid Withdrawal Scale. Five hundred and thirty urine screening tests were carried out randomly to detect additional consumption.

RESULTS

Sixty-seven opioid-dependent subjects (38 on methadone and 29 on buprenorphine) were enrolled in the study, and 53 completed it (30 subjects treated with buprenorphine and 23 subjects with racemic methadone). The subjects were comparable on all baseline measures. At the first follow-up (week 8), the buprenorphine-maintained group showed significantly less additional consumption of opioids (P = 0.013) compared with the methadone group. Patients retained in the buprenorphine or methadone programme (week 24) showed no significant differences in all quality of life scores. At the end of the study period, the buprenorphine-maintained group showed significantly less additional consumption of opioids (P = 0.001) and cocaine (P = 0.018) compared with the methadone group. The outcome measures for withdrawal symptoms after 24 weeks of treatment with buprenorphine showed slight advantages in stomach cramps, fatigue or tiredness, feelings of coldness and heart pounding.

CONCLUSIONS

These results suggest that buprenorphine treatment is as effective as methadone regarding effects on quality of life and withdrawal symptoms. Buprenorphine has the potential to reduce the harm caused by drug abuse. Further research is needed to determine if buprenorphine is more effective than methadone in particular subgroups of patients.

Buprenorphine versus methadone maintenance therapy: a randomized double-blind trial with 405 opioid-dependent patients

AIMS

To assess the efficacy of buprenorphine compared with methadone maintenance therapy for opioid dependence in a large sample using a flexible dosing regime and the marketed buprenorphine tablet.

DESIGN

Patients were randomized to receive buprenorphine or methadone over a 13-week treatment period in a double-blind, double-dummy trial.

SETTING

Three methadone clinics in Australia.

PARTICIPANTS

Four hundred and five opioid-dependent patients seeking treatment.

INTERVENTION

Patients received buprenorphine or methadone as indicated clinically using a flexible dosage regime. During weeks 1-6, patients were dosed daily. From weeks 7-13, buprenorphine patients received double their week 6 dose on alternate days.

MEASUREMENTS

Retention in treatment, and illicit opioid use as determined by urinalysis. Self-reported drug use, psychological functioning, HIV-risk behaviour, general health and subjective ratings were secondary outcomes.

FINDINGS

Intention-to-treat analyses revealed no significant difference in completion rates at 13 weeks. Methadone was superior to buprenorphine in time to termination over the 13-week period (Wald chi 2 = 4.371, df = 1, P = 0.037), but not separately for the single-day or alternate-day dosing phases. There were no significant between-group differences in morphine-positive urines, or in self-reported heroin or other illicit drug use. The majority (85%) of the buprenorphine patients transferred to alternate-day dosing were maintained in alternate-day dosing.

CONCLUSIONS

Buprenorphine did not differ from methadone in its ability to suppress heroin use, but retained approximately 10% fewer patients. This poorer retention was due possibly to too-slow induction onto buprenorphine. For the majority of patients, buprenorphine can be administered on alternate days.

1-year retention and social function after buprenorphine-assisted relapse prevention treatment for heroin dependence in Sweden: a randomised, placebo-controlled trial

BACKGROUND

The partial opiate-receptor agonist buprenorphine has been suggested for treatment of heroin dependence, but there are few long-term and placebo-controlled studies of its effectiveness. We aimed to assess the 1-year efficacy of buprenorphine in combination with intensive psychosocial therapy for treatment of heroin dependence.

METHODS

40 individuals aged older than 20 years, who met DSM-IV criteria for opiate dependence for at least 1 year, but did not fulfil Swedish legal criteria for methadone maintenance treatment were randomly allocated either to daily buprenorphine (fixed dose 16 mg sublingually for 12 months; supervised daily administration for a least 6 months, possible take-home doses thereafter) or a tapered 6 day regimen of buprenorphine, thereafter followed by placebo. All patients participated in cognitive-behavioural group therapy to prevent relapse, received weekly individual counselling sessions, and submitted thrice weekly supervised urine samples for analysis to detect illicit drug use. Our primary endpoint was 1-year retention in treatment and analysis was by intention to treat.

FINDINGS

1-year retention in treatment was 75% and 0% in the buprenorphine and placebo groups, respectively (p=0.0001; risk ratio 58.7 [95% CI 7.4-467.4]). Urine screens were about 75% negative for illicit opiates, central stimulants, cannabinoids, and benzodiazepines in the patients remaining in treatment.

INTERPRETATION

The combination of buprenorphine and intensive psychosocial treatment is safe and highly efficacious, and should be added to the treatment options available for individuals who are dependent on heroin.

Buprenorphine: an analgesic with an expanding role in the treatment of opioid addiction

Buprenorphine, a long-acting opioid with both agonist and antagonist properties, binds to mu-opioid (OP(3)), kappa-opioid (OP(2)), delta-opioid (OP(1)), and nociceptin (ORL-1) receptors. Its actions at these receptors have not been completely characterized, although buprenorphine is generally regarded as a mu-opioid receptor partial agonist and a kappa-opioid receptor antagonist. Its pharmacology is further complicated by an active metabolite, norbuprenorphine. Although buprenorphine can be used as an analgesic agent, it is of greater importance in the treatment of opioid abuse. Because of its partial agonist activity at mu-opioid receptors and its long half-life, buprenorphine has proven to be an excellent alternative to methadone for either maintenance therapy or detoxification of the opioid addict. Although buprenorphine may ultimately prove to be superior to methadone in the maintenance of the pregnant addict, its effects on the developing fetus must be carefully evaluated.

A randomized controlled trial of buprenorphine in the management of short-term ambulatory heroin withdrawal

AIM

To determine whether buprenorphine is more effective than clonidine and other symptomatic medications in managing ambulatory heroin withdrawal.

DESIGN

Open label, prospective randomized controlled trial examining withdrawal and 4-week postwithdrawal outcomes on intention-to-treat.

SETTING

Two specialist, out-patient drug treatment centres in inner city Melbourne and Sydney, Australia.

PARTICIPANTS

One hundred and fourteen dependent heroin users were recruited. Participants were 18 years or over, and with no significant other drug dependence, medical or psychiatric conditions or recent methadone treatment. One hundred and one (89%) participants completed a day 8 research interview examining withdrawal outcomes, and 92 (81%) completed day 35 research interview examining postwithdrawal outcomes.

INTERVENTIONS

Participants randomized to control (n = 56) (up to 8 days of clonidine and other symptomatic medications) or experimental (n = 58) (up to 5 days of buprenorphine) withdrawal groups. Following the 8-day withdrawal episode, participants could self-select from range of postwithdrawal options (naltrexone, substitution maintenance, or counselling).

MEASUREMENTS

Retention in withdrawal; heroin use during withdrawal; and retention in drug treatment 4 weeks after withdrawal.

SECONDARY OUTCOMES

Withdrawal severity; adverse events, and heroin use in the postwithdrawal period.

FINDINGS

The experimental group had better treatment retention at day 8 (86% versus 57%, P = 0.001, 95% CI for numbers needed to treat (NNT) = 3-8) and day 35 (62% versus 39%, P = 0.02, 95% CI for NNT = 4-18); used heroin on fewer days during the withdrawal programme (2.6 +/- 2.5 versus 4.5 +/- 2.3, P < 0.001, 95% CI = 1-2.5 days) and in the postwithdrawal period (9.0 +/- 8.2 versus 14.6 +/- 10, P < 0.01, 95% CI = 1.8-9.4); and reported less withdrawal severity. No severe adverse events reported.

CONCLUSIONS

Buprenorphine is effective for short-term ambulatory heroin withdrawal, with greater retention, less heroin use and less withdrawal discomfort during withdrawal; and increased postwithdrawal treatment retention than symptomatic medications.