Abuse liability of buprenorphine-naloxone tablets in untreated IV drug users

Buprenorphine/naloxone - one formulation that doesn't fit all: a case report

BACKGROUND

Sublingual buprenorphine, approved for treatment of opioid use disorder since 2002, is most commonly available in co-formulation with naloxone. Naloxone is an opioid antagonist minimally absorbed when sublingual (SL) buprenorphine/naloxone is taken as prescribed; it is thought to reduce potential for misuse via intravenous administration. However, growing data and clinical experience demonstrate that previously accepted assumptions about the pharmacokinetics of these medications may not apply to all patients.

CASE PRESENTATION

We present a patient whose adverse post-administration side effects on SL buprenorphine/naloxone resolved with transition to SL buprenorphine monoproduct.

DISCUSSION

Naloxone can be detected in nearly all patients taking SL buprenorphine/naloxone, though with apparent variability in clinical effect. In a minority of patients, naloxone can contribute to adverse and potentially treatment-limiting side effects. Furthermore, the naloxone component is commonly misunderstood by patients and providers and can foster mistrust in the therapeutic relationship if providers are perceived to be withholding a more tolerable formulation. Prescribers should have a low threshold to offer buprenorphine alone when clinically appropriate.

Self-Adjuvanting TLR7/8 Agonist and Fentanyl Hapten Co-Conjugate Achieves Enhanced Protection against Fentanyl Challenge

Currently approved pharmacotherapies for opioid use disorders (OUDs) and overdose reversal agents are insufficient to slow the spread of OUDs due to the proliferation of fentanyl. This is evident in the 31% rise in drug overdose deaths from 2019 to 2022, with rates increasing from 21.6 to 28.3 overdoses per 100,000 deaths. Vaccines are a potential alternative or adjunct therapy for the treatment of several substance use disorders (nicotine, cocaine) but have shown limited clinical success due to suboptimal antibody titers. In this study, we demonstrate that coconjugation of a Toll-like receptor 7/8 (TLR7/8) agonist (UM-3006) alongside a fentanyl-based hapten (F1) on the surface of the carrier protein cross-reactive material 197 (CRM) significantly increased generation of high-affinity fentanyl-specific antibodies. This demonstrated enhanced protection against fentanyl challenges relative to an unconjugated (admix) adjuvant control in mice. Inclusion of aluminum hydroxide (alum) adjuvant further increased titers and enhanced protection, as determined by analysis of fentanyl concentration in serum and brain tissue. Collectively, our findings present a promising approach to enhance the efficacy of antiopioid vaccines, underscoring the need for extensive exploration of TLR7/8 agonist conjugates as a compelling strategy to combat opioid use disorders.

Patterns of use and adverse events reported among persons who regularly inject buprenorphine: a systematic review

Background and Aims

Given the ongoing opioid crisis, novel interventions to treat severe opioid use disorder (OUD) are urgently needed. Injectable opioid agonist therapy (iOAT) with diacetylmorphine or hydromorphone is effective for the treatment of severe, treatment-refractory OUD, however barriers to implementation persist. Intravenous buprenorphine for the treatment of OUD (BUP iOAT) has several possible advantages over traditional iOAT, including a safety profile that might enable take-home dosing. We aimed to characterize injecting practices among real-world populations of persons who regularly inject buprenorphine, as well as associated adverse events reported in order to inform a possible future BUP iOAT intervention.

Methods

We conducted a systematic review. We searched MEDLINE, EMBASE, and PsycINFO from inception through July 2020 and used backwards citation screening to search for publications reporting on dose, frequency among persons who regularly inject the drug, or adverse events associated with intravenous use of buprenorphine. The review was limited to English language publications and there was no limitation on study type. Study quality and risk of bias was assessed using the Mixed Methods Appraisal Tool. Narrative synthesis was used in reporting the results.

Results

Eighty-eight studies were included in our review. Regular injection of buprenorphine was identified across diverse settings world-wide. Daily dose of oral buprenorphine injected was < 1–12 mg. Frequency of injection was 0–10 times daily. Adverse events could be characterized as known side effects of opioids/buprenorphine or injection-related complications. Most studies were deemed to be of low quality.

Conclusions

Extramedical, intravenous use of buprenorphine, continues to be documented. BUP iOAT may be feasible and results may inform the development of a study to test the efficacy and safety of such an intervention. Future work should also examine acceptability among people with severe OUD in North America. Our review was limited by the quality of included studies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12954-022-00695-5.

Effects of opioid receptor agonist and antagonist medications on electrocardiogram changes and presentation of cardiac arrhythmia: review article

BACKGROUND/PURPOSE

Mortality associated with prescription opioids has significantly increased over the past few decades and is considered a global pandemic. Prescribed opioids can cause cardiac arrhythmias, leading to fatal outcomes and unexpected death, even in the absence of structural cardiac disease. Despite the extent of cardiac toxicity and death associated with these medications, there is limited data to suggest their influences on cardiac electrophysiology and arrhythmias, with the exception of methadone. The goal of our review is to describe the possible mechanisms and to review the different ECG changes and arrhythmias that have been reported.

METHODS

A literature search was performed using Google Scholar, PubMed, Springer, Ovid, and Science Direct to identify studies that demonstrated the use of prescription opioids leading to electrocardiogram (ECG) changes and cardiac arrhythmias.

RESULTS

Many of the commonly prescribed opioid medications can uniquely effect the ECG, and can lead to the development of various cardiac arrhythmias. One of the most significant side effects of these drugs is QTc interval prolongation, especially when administered to patients with a baseline risk for QTc prolongation. A prolonged QTc interval can cause lethal torsades de pointes and ventricular fibrillation. Obtaining an ECG at baseline, following a dosage increase, or after switching an opioid medication, is appropriate in patients taking certain prescribed opioids. Opioids are often used first line for the treatment of acute and chronic pain, procedural sedation, medication opioid use disorders, and maintenance therapy.

CONCLUSIONS

To reduce the risk of cardiac arrhythmias and to improve patient outcomes, consideration of accurate patient selection, concomitant medications, electrolyte monitoring, and vigilant ECG monitoring should be considered.

Substances detected in used syringes of injecting drug users across 7 cities in Europe in 2017 and 2018: The European Syringe Collection and Analysis Project Enterprise (ESCAPE)

BACKGROUND AND AIMS

Injecting drug use is a matter of public health concern, associated with risks of overdoses, addiction and increased risk of bloodborne viral transmissions. Self-reported data on substances injected can be inaccurate or subject to bias or drug users might be oblivious to their injected substances or adulterations. Gathering of robust analytical information on the actual composition of substances injected might provide better information about the drugs that are being used. Therefore, this study aimed to analyse the residual content of discarded syringes collected across 7 European cities, collectively called the European Syringe Collection and Analysis Project Enterprise (ESCAPE).

METHODS

Used syringes were collected at street automatic injection kit dispensers or at harm-reduction services in Amsterdam, Budapest, Cologne, Glasgow, Helsinki, Lausanne and Paris. Two sampling periods were executed thus far, in 2017 and 2018. Qualitative chemical analysis of the content of used syringes was performed combining gas chromatographic (GC) and ultra(high)performance liquid chromatographic ((U)HPLC) analytical techniques with detection by mass spectrometry (MS).

RESULTS

Substances detected most frequently across both campaigns were cocaine, heroin, buprenorphine, amphetamines and synthetic cathinones. In Amsterdam, Cologne, Lausanne and Glasgow heroin and cocaine were the psychoactive substances most often detected, often in conjunction with each other. Helsinki showed a high presence of buprenorphine and amphetamines. In Budapest and Paris, synthetic cathinones were frequently detected. Less synthetic cathinones and cocaine was detected in 2018, whereas buprenorphine was detected almost twice as much. Inner-city variations were found, probably reflecting the types of people who inject drugs (PWID) in different areas of the city.

CONCLUSION

Overall, laboratory-confirmed local data on injected substances showed resemblance to national surveys done among PWID. However, the ESCAPE data also showed some interesting differences, showing it can be used for local interventions and complementing existing monitoring data.

Concomitant drugs with buprenorphine user deaths

BACKGROUND

Buprenorphine is abused in several countries notwithstanding its benefits as an analgesic and as an opioid agonist treatment medication. Benzodiazepines and alcohol have previously been associated with buprenorphine toxicity. This study elucidates the role of emerging concomitant drugs in different groups of buprenorphine user deaths.

METHODS

All cases in the Finnish national post-mortem toxicology database from 2016-2019 in which buprenorphine or norbuprenorphine was a laboratory finding in any post-mortem specimen and age at death of 15-64 years were investigated for cause and manner of death, concurrent drug and alcohol findings, age, and gender.

RESULTS

There were 792 deaths with a buprenorphine finding, of which buprenorphine was implicated in poisoning without other opioids in 271 cases (34 %). In this group of buprenorphine poisoning deaths, concomitant benzodiazepines were found in 94 % (clonazepam 53 %), illicit drugs in 63 %, gabapentinoids in 50 % (pregabalin 41 %), alcohol in 41 %, antidepressants in 32 %, and antipsychotics in 28 % of cases; only three deaths showed no benzodiazepines, alcohol, or gabapentinoids. Polydrug use was common regardless of the cause of death. In the age group 15 to 24 years, concomitant use of benzodiazepines and illicit drugs, and buprenorphine poisoning were more prevalent than in the age group 25-64 years.

CONCLUSIONS

The unprecedentedly high concomitant use of benzodiazepines in buprenorphine user deaths obscures other possible pharmacological risk factors for buprenorphine poisoning that could be relevant for prevention. Higher mortality in the younger age group suggests particularly unsafe drug use patterns that should be addressed.

Impact of Pharmacological Treatments for Opioid Use Disorder on Mortality

The use of pharmacological treatments for opioid use disorders, including methadone, buprenorphine and naltrexone has been associated with a reduction in mortality compared with illicit opioid use. However, these treatments can also contribute significantly to the risk of death. The opioid agonists methadone and buprenorphine achieve clinical efficacy in patients with an opioid use disorder through suppressing craving and diminishing the effectiveness of illicit opioid doses, while the antagonist naltrexone blocks the action of opioids. Pharmacological differences between opioid pharmacotherapies then create different temporal patterns of protection and mortality risk, different risks of relapse to illicit opioid use, and variations in direct and indirect toxicity, which are revealed in clinical and epidemiological studies. Induction onto methadone and the cessation of oral naltrexone treatment are associated with an elevated risk of opioid poisoning, which is not apparent in patients treated with buprenorphine or sustained-release naltrexone. Beyond drug-related mortality, these pharmacotherapies can impact a participant's risk of death. Buprenorphine may also have some advantages over methadone in patients with depressive disorders or cardiovascular abnormalities. Naltrexone, which is also commonly prescribed to manage problem alcohol use, may reduce deaths in chronic co-alcohol users. Understanding these pharmacologically driven patterns then guides the judicious choice of drug and dosing schedule and the proactive risk management that is crucial to minimising the risk of death in treatment.

Characterization of diverted buprenorphine use among adults entering corrections-based drug treatment in Kentucky

BACKGROUND

Illicit, medically unsupervised use of buprenorphine (i.e., "diverted use") among vulnerable and underserved populations, such as corrections-involved adults, remains underexplored.

METHODS

Survey data (2016-2017) collected as part of a clinical assessment of incarcerated adults entering corrections-based substance use treatment in Kentucky were analyzed. For years examined, 12,915 completed the survey. Removing cases for participants who did not reside in Kentucky for >6 months during the one-year pre-incarceration period (n = 908) resulted in a final sample size of 12,007.

RESULTS

Over a quarter of the sample reported past-year diverted buprenorphine use prior to incarceration and 21.8 % reported use during the 30-days prior to incarceration, using 6.5 months and 14.3 days on average, respectively. A greater proportion of participants who reported diverted buprenorphine use had previously been engaged with some substance use treatment (77.0 %) and reported greater perceived need for treatment (79.4 %) compared to those who did not report use. Use was more likely among participants who were younger, white, male, and who reported rural or Appalachian residence. Diverted buprenorphine users also evidenced extensive polydrug use and presented with greater substance use disorder severity. Non-medical prescription opioid, heroin, and diverted methadone use were associated with increased odds of diverted buprenorphine use while kratom was not. Diverted methadone use was associated with a 252.9 % increased likelihood of diverted buprenorphine use.

CONCLUSIONS

Diverted buprenorphine use among participants in this sample was associated with concerning high-risk behaviors and may indicate barriers to accessing opioid agonist therapies for corrections-involved Kentucky residents, particularly those in rural Appalachia.

Keeping Up with Clinical Advances: Opioid Use Disorder

Opioid use disorder (OUD) is a disorder that can lead to several negative outcomes, including overdose and death. A variety of opioids can be abused by individuals including both prescribed and non-prescribed opioids. Continued opioid use can be driven by negative affective states associated with opioid withdrawal. Several treatments exist in the field including medication assisted treatments such as methadone, buprenorphine, and naltrexone. Treatments such as clonidine and lofexidine can also be used to assist with decreasing withdrawal symptoms. Increasing adherence to treatment can further improve patient outcomes and promote continuation with treatment. A variety of methods to reduce relapse can also be utilized such as opioid agonists and maintenance therapy. According to the Centers for Disease Control, opioid overdoses contributed to 67.8% of overdose deaths in 2017.

Development of vaccines to treat opioid use disorders and reduce incidence of overdose

Vaccines offer a promising therapeutic strategy to treat substance use disorders (SUD). Vaccines have shown extensive preclinical proof of selectivity, safety, and efficacy against opioids, nicotine, cocaine, methamphetamine, and designer drugs. Despite clinical evaluation of vaccines targeting nicotine and cocaine showing proof of concept for this approach, no vaccine for SUD has yet reached the market. This review first discusses how vaccines for treatment of opioid use disorders (OUD) and reduction of opioid-induced fatal overdoses fit within the current medication assisted treatment (MAT) portfolio, and then summarizes ongoing efforts toward translation of vaccines targeting heroin, oxycodone, fentanyl, and other opioids. This article is part of the Special Issue entitled 'New Vistas in Opioid Pharmacology'.

Non-prescribed use of methadone and buprenorphine prior to opioid substitution treatment: lifetime prevalence, motives, and drug sources among people with opioid dependence in five Swedish cities

BACKGROUND

Opioid substitution treatment (OST) with methadone or buprenorphine is the most effective means of treating opioid dependence. If these substances are used by people who are not undergoing OST, they can however carry serious risks. This article examines the lifetime prevalence, motives, and drug sources for such use, as well as geographical differences in these variables.

METHODS

Structured interviews were conducted with 411 patients from 11 OST clinics in five Swedish cities. The researchers carried out 280 interviews on-site, while 131 interviews were conducted by specially trained patients through privileged access interviewing. Data were analyzed by frequency and average calculations, cross-tabulations, and χ2 tests.

RESULTS

The lifetime prevalence of non-prescribed use was 87.8% for methadone, 80.5% for buprenorphine, and 50.6% for buprenorphine/naloxone. Pseudo-therapeutic motives-avoiding withdrawal symptoms, staying clean from heroin, detoxification, or taking care of one's own OST-were commonly cited as driving the use, while using the drugs for euphoric purposes was a less common motive. Most respondents had bought or received the substances from patients in OST, but dealers were also a significant source of non-prescribed methadone and buprenorphine. Geographical differences of use, motives, and sources suggest that prescription practices in OST have a great impact on which substances are used outside of the treatment.

CONCLUSIONS

Experiences of non-prescribed use of methadone and buprenorphine are extremely common among those in OST in southern Sweden. As the use is typically driven by pseudo-therapeutic motives, increased access to OST might decrease the illicit demand for these substances. Buprenorphine/naloxone has a lower abuse potential than buprenorphine and should therefore be prioritized as the prescribed drug. Supervised dosage and other control measures are important provisions in the prevention of drug diversion and non-prescribed use among people not undergoing OST.

Overdose Risk and Client Characteristics Associated With the Injection of Buprenorphine at a Medically Supervised Injecting Center in Sydney, Australia

Background: Buprenorphine and buprenorphine/naloxone (BNX) were developed to improve the safety profile of opioid substitution treatment (OST) and reduce diversion and injection, yet continue to be injected, despite the risk of harm. Previous studies examining injection of these substances have relied on self-reported injection and overdose. Using data from the Uniting Medically Supervised Injecting Center (MSIC) in Sydney, this study aimed to assess the overdose risk associated with the use of buprenorphine and BNX and identify factors associated with injecting. Methods: Client data routinely collected from MSIC, a drug consumption room where clients can legally inject drugs under supervision, was used. Odds ratios (OR) to assess the risk of overdose and their associated 95% confidence intervals (95%CI) were calculated and compared to other substances. Univariate analysis using χ-square and multivariate logistic regressions were used to determine characteristics associated with buprenorphine and BNX injection. Results: Data from 1,020,782 injections by 15,832 individuals were analyzed. Risk of overdose was low for buprenorphine compared to other substances (OR 0.16; 95%CI: 0.07-0.19) and no overdoses occurred when BNX was injected. Injection of both buprenorphine and BNX was associated with male gender, homelessness, no income/reliance upon government payments, and prior imprisonment. Conclusions: Buprenorphine and BNX continue to be injected, albeit in small numbers. This is the first study to report on injection and overdose risk using direct observation, and has confirmed the lower overdose risk. MSIC clients who inject buprenorphine and BNX tend to be marginalized and may benefit from targeted harm reduction measures.

Understanding the use of diverted buprenorphine

BACKGROUND

Buprenorphine is approved in many countries for the treatment of opioid use disorder (OUD), but problems with diversion and abuse exist. There is a need to understand how and why patients use diverted buprenorphine, and whether barriers to access contribute to illicit use.

METHODS

Adults >18 years with DSM-IV criteria for substance use disorder and primarily using an opioid completed the online Survey of Key Informants' Patients (SKIP) between August and September 2016. The survey included closed- and open-ended questions regarding reasons for buprenorphine use with and without a prescription, sources of buprenorphine, route of administration, and barriers to treatment.

RESULTS

Of 303 respondents, 175 (58%) reported a history of diverted buprenorphine use, 65 (37%) of whom reported never receiving a prescription. The most common reasons for illicit buprenorphine use were consistent with therapeutic use: to prevent withdrawal (79%), maintain abstinence (67%), or self-wean off drugs (53%). Approximately one-half (52%) reported using buprenorphine to get high or alter mood, but few (4%) indicated that it was their drug of choice. Among respondents who had used diverted buprenorphine, 33% reported that they had issues finding a doctor or obtaining buprenorphine on their own. Most (81%) of these participants indicated they would prefer using prescribed buprenorphine, if available.

CONCLUSIONS

Although 58% of survey respondents reported a history of using diverted buprenorphine, the most frequently cited reasons for non-prescription use were consistent with therapeutic use. Diversion was partially driven by barriers to access, and an unmet need for OUD treatment persists.

Buprenorphine treatment formulations: Preferences among persons in opioid withdrawal management

BACKGROUND

In the current study, we examined factors predicting willingness to receive buprenorphine treatment and preferences for various buprenorphine formulations (oral, injection, implant) among persons in opioid withdrawal management.

METHODS

Participants were three hundred thirty-eight persons entering brief inpatient opioid withdrawal management programs at two sites. We used t-tests and Pearson χ2 - tests of independence to compare participants willing and unwilling to be prescribed buprenorphine in the future. Among persons willing to receive buprenorphine, we used multinomial logistic regression to estimate the adjusted effects of potential correlates of type of buprenorphine formulation preferred.

RESULTS

Participants averaged 33.9 (±9.5) years of age, 70.4% were male, 82.8% were White, and 11.0% were Latino/a. In all, 55.6% of participants had been prescribed buprenorphine in the past, and 54.7% were willing to use prescribed buprenorphine in the future. Those reporting past month illicit buprenorphine use and prior overdose were more willing to use prescribed buprenorphine. Of these (n = 180), most preferred daily buprenorphine formulations (tablet or film) (48.6%) over a weekly or monthly injection (23.1%) or bi-annual implant (28.3%).

CONCLUSIONS

Past buprenorphine prescription does not predict future willingness to restart. Among those willing to use buprenorphine, newer formulations of buprenorphine appealed to more than half of the participants.

Emerging Evidence for Cannabis' Role in Opioid Use Disorder

Introduction: The opioid epidemic has become an immense problem in North America, and despite decades of research on the most effective means to treat opioid use disorder (OUD), overdose deaths are at an all-time high, and relapse remains pervasive. Discussion: Although there are a number of FDA-approved opioid replacement therapies and maintenance medications to help ease the severity of opioid withdrawal symptoms and aid in relapse prevention, these medications are not risk free nor are they successful for all patients. Furthermore, there are legal and logistical bottlenecks to obtaining traditional opioid replacement therapies such as methadone or buprenorphine, and the demand for these services far outweighs the supply and access. To fill the gap between efficacious OUD treatments and the widespread prevalence of misuse, relapse, and overdose, the development of novel, alternative, or adjunct OUD treatment therapies is highly warranted. In this article, we review emerging evidence that suggests that cannabis may play a role in ameliorating the impact of OUD. Herein, we highlight knowledge gaps and discuss cannabis' potential to prevent opioid misuse (as an analgesic alternative), alleviate opioid withdrawal symptoms, and decrease the likelihood of relapse. Conclusion: The compelling nature of these data and the relative safety profile of cannabis warrant further exploration of cannabis as an adjunct or alternative treatment for OUD.

Buprenorphine alone or with naloxone: Which is safer?

To address concerns regarding the intravenous diversion of buprenorphine, a combined buprenorphine-naloxone (BUP-NLX) preparation was developed. The aim of this study is to compare health outcomes in opioid dependent patients treated with BUP and BUP-NLX. All patients treated with BUP and/or BUP-NLX in Western Australia between 2001 and 2010 were included in the study ( N = 3455). Patients were identified via State prescribing records and matched against the State mortality, hospital, and emergency department records. Rates of health events were examined and compared using Cox Proportional Hazard Models and Generalized Estimating Equations. While on treatment there was no significant difference between mortality rates in the two groups, mortality rates following the cessation of treatment were significantly higher in patients treated with BUP-NLX (adjusted hazard ratio: 1.59). Rates of hospitalization were significantly elevated in BUP-NLX patients (adjusted odds ratio: 1.17) compared with BUP treated patients; however, rates of hospitalization with a skin/subcutaneous diagnosis were significantly lower in BUP-NLX treated patients (adjusted odds ratio: 0.65). Off-treatment rates of both all-cause hospital admissions (adjusted odds ratio: 1.53) and hospital admissions with an opioid poisoning diagnosis (adjusted odds ratio: 1.59) were significantly elevated in BUP-NLX treated patients compared with BUP treated patients. The addition of naloxone does not appear to improve the safety profile of buprenorphine.

Effect of Buprenorphine Weekly Depot (CAM2038) and Hydromorphone Blockade in Individuals With Opioid Use Disorder: A Randomized Clinical Trial

IMPORTANCE

Buprenorphine is an efficacious, widely used treatment for opioid use disorder (OUD). Daily oral transmucosal formulations can be associated with misuse, diversion, and nonadherence; these limitations may be obviated by a sustained release formulation.

OBJECTIVE

To evaluate the ability of a novel, weekly, subcutaneous buprenorphine depot formulation, CAM2038, to block euphorigenic opioid effects and suppress opioid withdrawal in non-treatment-seeking individuals with OUD.

DESIGN, SETTING, AND PARTICIPANTS

This multisite, double-blind, randomized within-patient study was conducted at 3 controlled inpatient research facilities. It involved 47 adults with DSM-V moderate-to-severe OUD. The study was conducted from October 12, 2015 (first patient enrolled), to April 21, 2016 (last patient visit).

INTERVENTIONS

A total of five 3-day test sessions evaluated the response to hydromorphone (0, 6, and 18 mg intramuscular in random order; 1 dose/session/day). After the first 3-day session (ie, qualification phase), participants were randomized to either CAM2038 weekly at 24 mg (n = 22) or 32 mg (n = 25); the assigned CAM2038 dose was given twice, 1 week apart (day 0 and 7). Four sets of sessions were conducted after randomization (days 1-3, 4-6, 8-10, and 11-13).

MAIN OUTCOMES AND MEASURES

The primary end point was maximum rating on the visual analog scale for drug liking. Secondary end points included other visual analog scale (eg, high and desire to use), opioid withdrawal scales, and physiological and pharmacokinetic outcomes.

RESULTS

A total of 46 of 47 randomized participants (mean [SD] age, 35.5 [9] years; 76% male [n = 35]) completed the study. Both weekly CAM2038 doses produced immediate and sustained blockade of hydromorphone effects (liking maximum effect, CAM2038, 24 mg: effect size, 0.813; P < .001, and CAM2038, 32 mg: effect size, 0.753; P < .001) and suppression of withdrawal (Clinical Opiate Withdrawal Scale, CAM2038, 24 mg: effect size, 0.617; P < .001, and CAM2038, 32 mg: effect size, 0.751; P < .001). CAM2038 produces a rapid initial rise of buprenorphine in plasma with maximum concentration around 24 hours, with an apparent half-life of 4 to 5 days and approximately 50% accumulation of trough concentration from first to second dose (trough concentration = 0.822 and 1.23 ng/mL for weeks 1 and 2, respectively, with 24 mg; trough concentration = 0.993 and 1.47 ng/mL for weeks 1 and 2, respectively, with 32 mg).

CONCLUSIONS AND RELEVANCE

CAM2038 weekly, 24 and 32 mg, was safely tolerated and produced immediate and sustained opioid blockade and withdrawal suppression. The results support the use of this depot formulation for treatment initiation and stabilization of patients with OUD, with the further benefit of obviating the risk for misuse and diversion of daily buprenorphine while retaining its therapeutic benefits.

TRIAL REGISTRATION

Clinicaltrials.gov Identifier: NCT02611752.

The relationship between diversion-related attitudes and sharing and selling buprenorphine

OBJECTIVE

Buprenorphine medication-assisted treatment (B-MAT) is an efficacious and popular outpatient treatment for opioid use disorder. However, the likelihood of buprenorphine diversion is a public health concern. We examined the relationship between attitudes toward diversion as predictors of both sharing and selling buprenorphine.

METHOD

Participants (n=476) were patients undergoing short-term inpatient opioid detoxification. Multinomial logistic regression was used to estimate the adjusted association of sharing and selling buprenorphine with demographics, substance use behaviors, and attitudes toward sharing and selling buprenorphine.

RESULTS

Among the two hundred persons who had ever been prescribed buprenorphine (73.4% male, 89% heroin users), 50.5% reported they had shared buprenorphine and 28.0% reported they had sold buprenorphine. Controlling for other covariates, the odds of sharing buprenorphine were 3.17 (95% CI 1.21; 8.32) times higher for persons who agreed that it was "right to share buprenorphine with dope sick friends" than for those who did not agree with this attitude. Attitudes toward selling (OR 2.92; 95% CI 1.35; 6.21) and sharing (OR 4.12; 95% CI 1.64; 10.32) buprenorphine were the only significant correlates of selling, with the odds of selling exponentially greater among persons with favorable attitudes toward sharing or selling buprenorphine.

CONCLUSIONS

Although considered diversion, sharing B-MAT is normative among B-MAT patients. Assessing B-MAT patients' attitudes about diversion may help identify patients requiring enhanced oversight, education, or intervention aimed at modifying attitudes to reduce their likelihood to share or sell buprenorphine.

Probuphine® (buprenorphine implant): a promising candidate in opioid dependence

Opioid dependence leads to physical dependence and addiction which finally results in profound medical, psychological and social dysfunction. One of the useful medications for opioid dependence is buprenorphine, the partial opioid agonist, which is used alone or in combination with naloxone. However, buprenorphine is the victim of its own success due to its illicit use and accidental poisoning in children. Also, buprenorphine typically requires daily self-administration and its effectiveness heavily depends on patient adherence. So, poor treatment adherence results in ineffective treatment manifesting as craving and withdrawal symptoms. Short-term use of buprenorphine in opioid dependence is also often followed by relapse. Buprenorphine when used sublingually often results in inadequate or fluctuating blood concentrations and poorer treatment retention compared with methadone. All of these led to the development of Probuphine®, a polymeric matrix composed of ethylene vinyl acetate and buprenorphine in the form of implants, that are implanted subdermally in office practice and deliver the active drug over 6 months. Buprenorphine release from such implant is fairly consistent, avoiding plasma peaks and troughs, and the implant is also reported to be safe. In this review article, we have highlighted these aspects of treatment of opioid addiction, stressing on the pharmacology of buprenorphine and Probuphine®, and relevant clinical trials addressing the efficacy and safety of Probuphine®. This sustained-release implantable formulation of buprenorphine has the potential to be a suitable alternative to daily or alternate day sublingual buprenorphine which can thereby eliminate the need for daily supervision, minimizing fluctuations in plasma concentrations, and allowing these patients to reduce clinic or pharmacy visits.

Do all screening immunoassay positive buprenorphine samples need to be confirmed?

Background Interference from opiates in the Microgenics CEDIA® Buprenorphine assay is known to produce false-positive buprenorphine screening immunoassay results necessitating confirmatory buprenorphine testing by chromatography/mass spectrometry methods. Method We reviewed data on falsely positive buprenorphine immunoassay screen (cut-off ≥ 5  µg/L) but negative for buprenorphine by gas chromatography mass spectrometry (cut-off ≥ 5  µg/L) and had a positive opiate immunoassay result (cut-off ≥ 300  µg/L). The results were collected over three months, and the data were evaluated to determine whether there is an opiate immunoassay screen concentration below which a false-positive buprenorphine result will not occur. Results We found that cross-reactivity in the CEDIA® buprenorphine immunoassay by opiates at concentrations <2000  µg/L will not cause a false-positive buprenorphine result. After changing our practice to not proceed with confirmatory buprenorphine gas chromatography mass spectrometry assay when the opiate screening concentration is below an even more conservative cut-off of <1500  µg/L, we estimate a potential cost-saving of AU$ 17,810 per year without compromising clinical care. Conclusion Samples with CEDIA® opiate immunoassay result <2000  µg/L and a positive CEDIA® buprenorphine immunoassay screen do not require confirmatory testing for buprenorphine.

Exploring prison buprenorphine misuse in the United Kingdom: a qualitative study of former prisoners

The United Kingdom Ministry of Justice recently highlighted the extent of buprenorphine (Subutex) misuse in English andWelsh prisons, naming it the third most misused drug overall. Yet little is known regarding how illicit buprenorphine is obtained in prison and what influences prisoners to use it. Qualitative research was used to explore prison drug using practices. Thirty men who were former prisoners with a history of injecting drug use were interviewed in depth about their illicit prison drug use, including buprenorphine. Interviews were conducted over 18 months, from August 2006 to January 2008 and were analysed using Framework. The misuse of Subutex by snorting emerged as a significant theme. Accounts suggested that the diversion of prison prescribed Subutex was widespread and prisoners used various tactics to obtain the medication. Various complex and interlinked reasons were given to explain why Subutex was snorted in prison. The main motivation for snorting was to experience a prolonged euphoric opiate effect, believed to help to combat the boredom of being in prison. The price of illicit Subutex in prison was linked to its availability, but it was generally cheaper than heroin, thus contributing to its use. Participants'narratives identified the belief that snorting Subutex in prison was not risk free, but risks were lower than continuing to use other drugs, particularly injecting illicit opiates. The implications of prison Subutex misuse for prisoners, prison medical services, commissioners, and prescribing policy and practice are discussed.

Buprenorphine Prescribing: To Expand or Not to Expand

As a result of the prescription opioid epidemic in the United States, there has been an increasing need for effective treatment interventions, both pharmacological and nonpharmacological. Buprenorphine has emerged as a critical component of the treatment of opioid use disorder, yet its adoption has not been without some concerns. This article first reviews the pharmacology, clinical use, and US legislative action related to buprenorphine, followed by a discussion of the misuse and diversion of buprenorphine in the United States as well as internationally. We then explore the impact of buprenorphine abuse as well as discussing strategies for its reduction, including changes in policy, prescription and pharmacy monitoring, and continuing medical education for guiding and improving clinical practice.

Intranasal buprenorphine alone and in combination with naloxone: Abuse liability and reinforcing efficacy in physically dependent opioid abusers

BACKGROUND

Buprenorphine can be abused by the intranasal route. This study sought to examine the relative abuse liability and reinforcing efficacy of intranasal buprenorphine compared to intranasal buprenorphine/naloxone in opioid-dependent individuals.

METHODS

Eleven healthy male and female volunteers physically dependent on short-acting opioids resided as inpatients during participation in this double blind, within subject, placebo-controlled study. Participants were maintained on oxycodone (30 mg/q.i.d., p.o.) throughout the 6-week study. Eight pairs of experimental sessions were conducted at ≥48 h intervals to examine the pharmacodynamic profile (Sample) and reinforcing efficacy (Self-administration the following day) of intranasal placebo, oxycodone (60 mg), buprenorphine (2, 8 & 16 mg) and buprenorphine/naloxone (2/0.5, 8/2 & 16/4 mg). Subjective, observer-rated and physiological measures were collected to assess the magnitude of opioid agonist and antagonist effects. A progressive ratio self-administration procedure assessed choices for drug versus money.

RESULTS

All active doses produced opioid agonist-like effects (e.g., increased ratings of "liking," and miosis) compared to placebo. The effects of buprenorphine and buprenorphine/naloxone were not reliably dose-dependent. Intranasal buprenorphine/naloxone elicited modest and transient opioid withdrawal-like effects in the first hour post-drug administration, while simultaneously blunting or blocking the early onset of agonist effects seen with buprenorphine alone. All active doses of buprenorphine were self-administered more than placebo, but buprenorphine/naloxone doses were not.

CONCLUSIONS

These data confirm that intranasal buprenorphine/naloxone has deterrent properties related to transient withdrawal effects that likely decrease its desirability for misuse compared to buprenorphine in opioid-dependent individuals maintained on short-acting opioids.

A mimic of soft tissue infection: intra-arterial injection drug use producing hand swelling and digital ischemia

BACKGROUND

Inadvertent intra-arterial injection of illicit substances is a known complication of injection drug use and can lead to severe complications, including infection, ischemia and compartment syndrome. Identifying complications of intra-arterial injection can be difficult, as clinical manifestations overlap with other more common conditions such as cellulitis and soft tissue infection, and a history of injection drug use is frequently not disclosed.

METHODS

A 37-year-old male patient presented with 24 hours of right hand pain, erythema and swelling. Despite classic "track marks", he denied a history of injection drug use, and vascular insults were not initially considered. After failing to respond to three days of aggressive treatment for suspected deep-space infection, an arteriogram demonstrated findings consistent with digital ischemia of embolic etiology.

RESULTS

As a result of the delay in diagnosis, the lesion was not amenable to reperfusion and the patient required amputation of the distal digit.

CONCLUSION

Practitioners should be alert to the possibility of intra-arterial injection and resulting complications when evaluating unusual extremity infections or unexplained ischemic symptoms, even in the absence of a definite history of injection drug use.

Abuse potential of intranasal buprenorphine versus buprenorphine/naloxone in buprenorphine-maintained heroin users

In spite of the clinical utility of buprenorphine, parenteral abuse of this medication has been reported in several laboratory investigations and in the real world. Studies have demonstrated lower abuse liability of the buprenorphine/naloxone combination relative to buprenorphine alone. However, clinical research has not yet examined the utility of the combined formulation to deter intranasal use in a buprenorphine-maintained population. Heroin-using volunteers (n = 12) lived in the hospital for 8-9 weeks and were maintained on each of three sublingual buprenorphine doses (2, 8, 24 mg). Under each maintenance dose, participants completed laboratory sessions during which the reinforcing and subjective effects of intranasal doses of buprenorphine (8, 16 mg), buprenorphine/naloxone (8/2, 8/8, 8/16, 16/4 mg) and controls (placebo, heroin 100 mg, naloxone 4 mg) were assessed. Intranasal buprenorphine alone typically produced increases in positive subjective effects and the 8 mg dose was self-administered above the level of placebo. The addition of naloxone dose dependently reduced positive subjective effects and increased aversive effects. No buprenorphine/naloxone combination dose was self-administered significantly more than placebo. These data suggest that within a buprenorphine-dependent population, intranasal buprenorphine/naloxone has reduced abuse potential in comparison to buprenorphine alone. These data strongly argue in favor of buprenorphine/naloxone rather than buprenorphine alone as the more reasonable option for managing the risk of buprenorphine misuse.

A review of buprenorphine diversion and misuse: the current evidence base and experiences from around the world

Outpatient opioid addiction treatment with sublingual buprenorphine pharmacotherapy has rapidly expanded in the United States and abroad, and, with this increase in medication availability, there have been increasing concerns about its diversion, misuse, and related harms. This narrative review defines the behaviors of diversion and misuse, examines how the pharmacology of buprenorphine alone and in combination with naloxone influence its abuse liability, and describes the epidemiological data on buprenorphine diversion and intravenous misuse, risk factors for its intravenous misuse, and the unintended consequences of misuse and diversion. Physician practices to prevent, screen for, and therapeutically respond to these behaviors, which are a form of medication nonadherence, are discussed, and gaps in knowledge are identified. Outpatient opioid addiction treatment with sublingual buprenorphine pharmacotherapy experiences from other countries that have varied health care systems, public policies, and access to addiction treatment are shared to make clear that diversion and misuse occur across the world in various contexts, for many different reasons, and are not limited to buprenorphine. Comparisons are made with other opioids with known abuse liability and medications with no known abuse. The objective was to facilitate understanding of diversion and misuse so that all factors influencing their expression (patient and provider characteristics and public policy) can be appreciated within a framework that also recognizes the benefits of addiction treatment. With this comprehensive perspective, further careful work can help determine how to minimize these behaviors without eroding the current benefits realized through improved addiction treatment access and expansion.

Buprenorphine maintenance program with contracted work/education and low tolerance for non-prescribed drug use: a cohort study of outcome for women and men after seven years

BACKGROUND

A seven-year follow-up of heroin dependent patients treated in a buprenorphine-maintenance program combining contracted work/education and low tolerance for non-prescribed drug use. Gender-specific differences in outcome were analysed.

METHODS

A consecutively admitted cohort of 135 men and 35 women, with eight years of heroin abuse/dependence on average was admitted to enhanced buprenorphine maintenance treatment. Standardized interviews, diagnostic assessments of psychiatric disorders and psychosocial conditions were conducted at admission and at follow-ups. Outcome associated with gender was reported for abstinence, retention, psychiatric symptoms, employment and criminal convictions.

RESULTS

148 patients started treatment. After seven years, 94/148 patients (64%) were retained in the program, employed and abstinent from drugs and alcohol. Women had more continuous abstinence, retention and employment than men (76% versus 60%). After one year patients with a high-risk consumption of alcohol were no longer heavy consumers of alcohol and remained so throughout the study (p < .001). All women regained custody of their children. At admission, more women than men had been admitted for psychiatric disorders (70%/44%) and to compulsory care for substance abuse (30%/18%). Initial gender differences of psychiatric co-morbidity decreased and were no longer significant after one year. More men than women had been imprisoned (62% versus 27%) or in non-institutional care (80% versus 49%). Criminal convictions were reduced from 1751 convictions at admission to 742 (58%) after seven years. Eight patients in the entire cohort died over the 7 years (0.7% per year). One patient died in the completers group while still in the program (0.1% per year).

CONCLUSIONS

After seven years, two thirds of the patients in the program were abstinent and employed. Convictions ceased in the completers group. One patient died in the completers group. Women had superior long-term outcome compared to men: more continuous abstinence, employment and fewer convictions. Women also lived with their children to a higher extent than men. The positive outcome highlights the importance of maintaining high structure in combining pharmacological treatment with a focus on employment and psychological treatment and low tolerance for non-prescribed drug use.

Illicit use of opioid substitution drugs: prevalence, user characteristics, and the association with non-fatal overdoses

BACKGROUND AND AIMS

Diversion of opioid substitution drugs (OSD) is of public concern. This study examined the prevalence, frequency, and predictors of illicit OSD use in a group of injecting drug users (IDUs) and assessed if such use was associated with non-fatal overdoses.

METHODS

Semi-annual cross-sectional interviews conducted in Oslo, Norway (2006-2013), from 1355 street-recruited IDUs. Hurdle, logistic, and multinomial regression models were employed.

RESULTS

Overall, 27% reported illicit OSD use in the past four weeks; 16.8% methadone, 12.5% buprenorphine, and 2.9% both drugs. Almost 1/10 reported at least one non-fatal overdose in the past four weeks, and roughly 1/3 reported such experience in the past year. Use of additional drugs tended to be equally, or more prevalent among illicit OSD users than other IDUs. In terms of illicit OSD use being a risk factor for non-lethal overdoses, our results showed significant associations only for infrequent buprenorphine use (using once or less than once per week). Other factors associated with non-fatal overdoses included age, education, homelessness, as well as the benzodiazepines, stimulants, and heroin use.

CONCLUSIONS

Users of diverted OSD may represent a high-risk population, as they used more additional drugs and used them more frequently than other IDUs. However, illicit OSD use may be less harmful than previously assumed. After accounting for an extensive set of covariates, only infrequent illicit buprenorphine use, but not methadone use, was associated with non-fatal overdoses.

Considerations on the role of buprenorphine in recovery from heroin addiction from a UK perspective

The United Kingdom Drug Strategy emphasises recovery as a key focus in the treatment of drug dependence. A framework for recovery is defined in the Recovery-Orientated Drug Treatment report, written by an expert working group, and comprises four key phases: engagement and stabilisation, including the establishment of treatment goals; preparation for change, involving engagement in psychosocial and pharmacological interventions; active change, including detoxification and medical withdrawal; and completion, including interventions that strengthen community integration. A body of evidence supports the benefits of buprenorphine, a partial agonist at mu opioid receptors, in supporting individualised recovery based on this framework, specifically in relation to the potential for rapid stabilisation, flexibility to transition to other treatment options or achieve abstinence, effective blocking of on-top use of illicit drugs, the treatment of comorbidities through the minimisation of drug-drug interactions, and a good safety profile. In addition, the newer abuse-deterrent formulation of buprenorphine combined with the opioid antagonist naloxone is likely to strengthen recovery-orientated systems of care due to its potential to reduce misuse and diversion. Progress through the recovery journey and the ability to sustain recovery will depend on individual needs and goals and on the amount of recovery capital that individuals have developed.

Pharmacological treatments for drug misuse and dependence

INTRODUCTION

Substance misuse disorder (DSM-5) remains a major health challenge. Harm reduction is the initial treatment goal, by reducing or eliminating non-prescribed drug use. Eventual abstinence is the ultimate harm reduction goal. However the scope for evidence-based pharmacological interventions remains limited.

AREAS COVERED

The paper takes a pragmatic clinical approach to existing and developing pharmacotherapies for substance misuse. Dependence may be characterised as a cycle with three stages: binge/intoxication, withdrawal/negative affect and preoccupation/anticipation (craving). Each of these stages may be the focus of pharmacotherapeutic intervention, and current literature is discussed which is of relevance to the practising clinician. Dependence on opiates, stimulants, cannabis and prescribed medications including benzodiazepines and the current treatments are addressed.

EXPERT OPINION

Possible pharmacotherapies of the future include anti-craving medications, which are still incompletely understood. Other developments include ultra-long-acting formulations, some of which have already been produced and are being studied or are in early clinical practice. A completely new line of investigation has been drug 'vaccines', whereby the body is stimulated to produce antibodies to, for example, cocaine and nicotine. Despite a number of evidence-based strategies for the treatment of substance misuse disorder, the range of licensed pharmacological treatment choices nevertheless remains narrow.

The current status of opioid maintenance treatment in France: a survey of physicians, patients, and out-of-treatment opioid users

Aim

Project Access France was a national survey designed to provide real-world observations on the status of opioid dependence treatment in France.

Methods

The views of physicians (n=100), patients (n=130), and out-of-treatment opioid users (n=33) were collected via interviews and questionnaires.

Results

Physicians reported being moderately satisfied with treatment programs in their area (rating 6.9 out of 10). Most physicians (82%) reported being concerned about misuse and diversion of medication-assisted treatment (MAT) medications and 50% identified psychosocial/behavioral counseling as the key change that would most improve patient care. Among patients, the mean number of previous MAT episodes was low (1.5); 78% reported that it was easy to access a doctor to undergo MAT; 14% reported regularly or sometimes using heroin; misuse and diversion were reported in 15% and 39% of patients, respectively; and 57% of patients were not receiving psychosocial help. Out-of-treatment opioid users reported using drugs on a regular basis (42% regularly used heroin) and cited ‘not wanting to give up drugs completely’ as the most frequent reason for staying out of MAT.

Conclusion

This survey highlights a number of positive features of the open-access, GP-based treatment model for opioid dependence in France. Challenges remain with regard to continued misuse/diversion of MAT medications and limited patient access to psychosocial support.

Rewarding or aversive effects of buprenorphine/naloxone combination (Suboxone) depend on conditioning trial duration

Buprenorphine is used as a sublingual medication in the treatment of opioid dependence. However, its misuse by i.v. injection may limit its acceptability and dissemination. A buprenorphine/naloxone (ratio 4:1) combination has been developed to reduce diversion and abuse. So far, the relevance of this combination has not been investigated in the animal models traditionally used to study the reinforcing effects of drugs of abuse. The aim of this study was to compare the rewarding effects, assessed by conditioned place preference (CPP), of buprenorphine and buprenorphine/naloxone combination following i.v. administration in mice. Animals were treated with different doses of buprenorphine or buprenorphine/naloxone combination (ratio 4:1), and CPP conditioning trial duration was 5 or 30 min. At the longest trial duration, a bell-shaped dose-response curve was obtained with buprenorphine, which was shifted significantly to the right with naloxone combination. At the shortest trial duration, an aversive effect was observed with the buprenorphine/naloxone combination in animals, involving opioid receptor-like 1 (ORL1). These findings may explain the discrepancies reported in the literature as some authors have shown a reduced buprenorphine/naloxone misuse compared to buprenorphine in opioid abusers, while others have not.

Factors contributing to the rise of buprenorphine misuse: 2008-2013

OBJECTIVE

The purpose of the present study was to examine the motivations underlying the use of buprenorphine outside of therapeutic channels and the factors that might account for the reported rapid increase in buprenorphine misuse in recent years.

METHODS

This study used: (1) a mixed methods approach consisting of a structured, self-administered survey (N=10,568) and reflexive, qualitative interviews (N=208) among patients entering substance abuse treatment programs for opioid dependence across the country, centered on opioid misuse patterns and related behaviors; and (2) interviews with 30 law enforcement agencies nationwide about primary diverted drugs in their jurisdictions.

RESULTS

Our results demonstrate that the misuse of buprenorphine has increased substantially in the last 5 years, particularly amongst past month heroin users. Our quantitative and qualitative data suggest that the recent increases in buprenorphine misuse are due primarily to the fact that it serves a variety of functions for the opioid-abusing population: to get high, manage withdrawal sickness, as a substitute for more preferred drugs, to treat pain, manage psychiatric issues and as a self-directed effort to wean themselves off opioids.

CONCLUSION

The non-therapeutic use of buprenorphinehas risen dramatically in the past five years, particularly in those who also use heroin. However, it appears that buprenorphine is rarely preferred for its inherent euphorigenic properties, but rather serves as a substitute for other drugs, particularly heroin, or as a drug used, preferable to methadone, to self-medicate withdrawal sickness or wean off opioids.

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.

Interruption of medication-assisted treatment for opioid dependence: insights from the UK

Purpose

– The purpose of this paper is to identify risk factors for interruptions in opioid dependence treatment and barriers to (re) entering effective treatment through real-world insight on current opioid dependence treatment in the UK.

Design/methodology/approach

– Project Access UK, a national survey deployed across multiple regions in England, Wales and Scotland, collected data on the perspectives of patients receiving medication-assisted treatment (MAT) for opioid dependence (n=248), out-of-treatment opioid users (n=196), and physicians (n=100).

Findings

– Both patients and users reported multiple prior episodes of MAT and detoxification. Among patients, 57 per cent reported continuing illicit drugs use in addition to their treatment, 25 per cent had misused (injected or snorted) and 30 per cent had diverted (sold or given away) prescribed opioid medications. Diverted medications were currently being used by 26 per cent of out-of-treatment users; of these, 21 per cent used methadone. Supervised dosing was rated as the condition of treatment with the biggest impact on daily life. Daily supervision was a requirement for 44, 34 and 23 per cent of patients receiving methadone, mono-buprenorphine and buprenorphine-naloxone, respectively.

Practical implications

– Interruptions to opioid dependence treatment in various forms can hamper the recovery of opioid-dependent patients. The benefits of MAT may not be fully realised if treatment is interrupted due to compliance failure, or inflexible treatment programmes leading to premature treatment exit. These findings serve to highlight areas in which treatment disruption can potentially be addressed.

Originality/value

– Consideration of these findings may aid in the optimisation of treatment delivery practices to better meet the UK policy of recovery, and ultimately improve patient outcomes.

Buprenorphine-naloxone therapy in pain management

Buprenorphine-naloxone (bup/nal in 4:1 ratio; Suboxone; Reckitt Benckiser Pharmaceuticals Incorporation, Richmond, VA) is approved by the Food and Drug Administration for outpatient office-based addiction treatment. In the past few years, bup/nal has been increasingly prescribed off-label for chronic pain management. The current data suggest that bup/nal may provide pain relief in patients with chronic pain with opioid dependence or addiction. However, the unique pharmacological profile of bup/nal confers it to be a weak analgesic that is unlikely to provide adequate pain relief for patients without opioid dependence or addiction. Possible mechanisms of pain relief by bup/nal therapy in opioid-dependent patients with chronic pain may include reversal of opioid-induced hyperalgesia and improvement in opioid tolerance and addiction. Additional studies are needed to assess the implication of bup/nal therapy in clinical anesthesia and perioperative pain management.