Buprenorphine: blending practice and research

Real-World Dispensing of Buprenorphine in California during Prepandemic and Pandemic Periods

INTRODUCTION

The opioid overdose crisis in the United States has become a significant national emergency. Buprenorphine, a primary medication for individuals coping with opioid use disorder (OUD), presents promising pharmacokinetic properties for use in primary care settings, and is often delivered as a take-home therapy. The COVID-19 pandemic exacerbated the scarcity of access to buprenorphine, leading to dire consequences for those with OUD. Most existing studies, primarily focused on the immediate aftermath of the COVID-19 outbreak, highlight the challenges in accessing medications for opioid use disorder (MOUDs), particularly buprenorphine. However, these studies only cover a relatively short timeframe.

METHODS

To bridge this research gap, in our study, we utilized 33 months of California's prescription drug monitoring program (PDMP) data to provide insights into real-world buprenorphine dispensing trends since the onset of the pandemic from 2018 to 2021, focusing on outcomes such as patient counts, prescription volumes, prescriber involvement, days' supply, and dosage. Statistical analysis employed interrupted time series analysis to measure changes in trends before and during the pandemic.

RESULTS

We found no significant impact on patient counts or prescription volumes during the pandemic, although it impeded the upward trajectory of prescriber numbers that was evident prior to the onset of the pandemic. An immediate increase in days' supply per prescription was observed post-pandemic.

CONCLUSION

Our findings differ in comparison to previous data regarding the raw monthly count of patients and prescriptions. The analysis encompassed uninsured patients, offering a comprehensive perspective on buprenorphine prescribing in California. Our study's insights contribute to understanding the impact of COVID-19 on buprenorphine access, emphasizing the need for policy adjustments.

Factors associated with clinician treatment recommendations for patients with a new diagnosis of opioid use disorder

BACKGROUND

This study examined factors associated with treatment recommendations for patients with a new diagnosis of opioid use disorder (OUD), comparing recommendations for patients with clear signs of OUD versus those with lower likelihood of OUD.

METHODS

The study conducted a retrospective medical chart review in a randomly selected national sample of 520 Veteran Health Administration patients with a new opioid-related electronic health record (EHR) diagnosis from 2012 to 2017. The study categorized patients as having "high likelihood" or "lower likelihood of OUD" based on the presence or absence of clinician documentation in medical records of specific qualifying criteria (e.g., clinician documentation of patient meeting diagnostic criteria for OUD, etc). Analyses examined the association between baseline demographic and clinical characteristics with recommendations for medication and other treatments for OUD.

RESULTS

Among patients with a new diagnosis of OUD, 28.7 % (n = 149) were recommended medication treatment, 52.5 % (n = 273) were recommended specialty substance use disorder (SUD) treatment, and 41.9 % (n = 218) were recommended treatment in non-SUD mental health settings. In adjusted models, high likelihood of OUD (AOR 8.31, 95 % CI 4.81-15.03) was strongly associated with the clinician recommending medications for OUD, while age 56-75 (compared to <35, AOR 0.36, 95 % CI 0.18-0.69), stimulant use disorder (AOR 0.28, 95 % CI 0.15-0.53), and rural residence (AOR 0.51, 95 % CI 0.30-0.85) were associated with lower likelihood of being recommended medication treatment.

CONCLUSIONS

Differentiating among patients with EHR diagnoses of OUD to identify the subset with higher likelihood of underlying OUD is important to accurately understand OUD treatment rates and disparities. However, even among patients with a clear diagnosis of OUD, medication treatment is still recommended less often than other treatments, suggesting interventions are needed to encourage clinicians to prioritize medication treatment as a first-line treatment, especially for older, rural patients and those with polysubstance use.

Using buprenorphine to treat patients with opioid use disorder

The US opioid epidemic is a complex problem that has resulted in legislative actions to make treatment more accessible to patients. Physician assistants (PAs) have taken an active role in expanding their scope of practice to keep up with treatment needs. This article describes opioid use disorder in the United States, treatment gaps, safe treatment with buprenorphine, and PA prescriptive authority.

Kappa opioid receptor antagonism: Are opioids the answer for treatment resistant depression?

Introduction:

Past trials of buprenorphine (BUP) in the treatment of major depressive disorder (MDD) have displayed favorable results, although its clinical utility was limited by the risk of abuse or physical dependence. By combining BUP with samidorphan (SAM), the euphoric high is negated by an opposing mechanism, which theoretically reduces addictive-like properties while allowing the antidepressant properties to remain. As such, the objective of this article is to analyze the results of BUP/SAM premarketing clinical trials as adjunctive treatment for treatment-resistant MDD.

Methods:

A comprehensive PubMed/MEDLINE search was conducted through November 9, 2017, using the following search terms: depression, samidorphan, buprenorphine, ALKS-5461. Additional data were obtained from Clinicaltrials.gov and resources included in the present study. All English-language clinical trials evaluating the combination of BUP/SAM in the treatment of MDD were included.

Results:

A few premarketing studies have evaluated the efficacy and safety of BUP/SAM combination as adjunctive treatment in patients with treatment-resistant MDD. The FORWARD-1 through FORWARD-5 trials concluded (1) the most effective dosing ratio of BUP/SAM to reduce abuse potential was 1:1; (2) statistically significant changes in scores from baseline on the Montgomery-Asberg Depression Rating Scale were noted for the 2 mg/2 mg dose compared with placebo; and (3) the most commonly reported adverse effects were nausea, dizziness, and fatigue.

Discussion:

Buprenorphine/samidorphan has shown favorable results for efficacy and tolerability in premarketing studies evaluating its use as adjunctive therapy for treatment-resistant MDD. Its novel mechanism targeting the opioid pathway may serve as a promising antidepressant devoid of abuse potential.

Research Note — Review of Corrections-Based Therapy for Opiate-Dependent Patients: Implications for Buprenorphine Treatment among Correctional Populations

Inmates with a history of opiate dependence represent a substantial proportion of the correctional population in the United States. Opiate use has negative consequences for both the inmate and society, including increased recidivism rates, increased infectious disease prevalence, avoidable emergency room use, decreased access to primary care services, and overdose. While there have been great successes in community-based treatment of opiate dependence, these successes have not yet been achieved in correctional settings. This paper reviews the pharmacological treatment options for opiate-dependent inmates, along with potential application for community-to-correctional approaches. The recent approval by the Food and Drug Administration (FDA) of physician-prescribed buprenorphine and the new opportunities it presents to corrections-based treatment are also explored in depth. Successful implementation of such strategies is likely to result in desirable health and social outcomes for both the inmate and the community at large.

The Supply of Physicians Waivered to Prescribe Buprenorphine for Opioid Use Disorders in the United States: A State-Level Analysis

OBJECTIVE

The U.S. Food and Drug Administration's approval of buprenorphine in 2002 expanded options for treating opioid use disorder (OUD). Physicians who intend to treat OUD patients with buprenorphine must seek a waiver to prescribe it, which may contribute to state-by-state variation in the supply of waivered physicians.

METHOD

This study integrates data extracted from the U.S. Drug Enforcement Agency's database of waivered physicians with state-level indicators of the macro environment, health-related resources, and treatment demand.

RESULTS

In December 2013, the average state had 8.0 waivered physicians per 100,000 residents (SD = 5.2). Large regional differences between states in the Northeast relative to states in the Midwest, South, and West were observed. The percentage of residents covered by Medicaid as well as the population-adjusted availability of opioid treatment programs and substance use disorder treatment facilities were positively associated with buprenorphine physician supply. Buprenorphine physician supply was positively correlated with states' rates of overdose deaths, suggesting that physicians may seek the waiver in response to the magnitude of the opioid problem in their state.

CONCLUSIONS

States with greater health-related resources, particularly in terms of the supply of opioid treatment programs and substance use disorder treatment programs, had more waivered physicians in 2013. The finding regarding Medicaid coverage suggests that states implementing Medicaid expansion under health reform may experience additional growth in buprenorphine physician supply. However, large regional disparities in the supply of waivered physicians may impede access to care for many Americans with OUD.

States' implementation of the Affordable Care Act and the supply of physicians waivered to prescribe buprenorphine for opioid dependence

BACKGROUND

Although the Affordable Care Act (ACA) is anticipated to affect substance use disorder (SUD) treatment, its impact on the supply of physicians waivered to treat opioid dependence with buprenorphine has not been considered. This study examined whether states more supportive of ACA, meaning those that had opted to expand Medicaid and establish a state-based health insurance exchange, experienced greater growth in physician supply than less supportive states.

METHODS

Buprenorphine physician supply, including total physician supply, supply of 30-patient physicians, and supply of 100-patient physicians per 100,000 state residents, was measured from June 2013 to May 2015. State characteristics were drawn from multiple secondary sources, with states categorized as ACA-supportive, ACA-hybrid (where states either expanded Medicaid or established a state-based exchange), or ACA-resistant (where states took neither action). Mixed effects regression was used to estimate state-level growth curves to test whether rates of growth varied by states' approaches to implementing ACA.

RESULTS

The supply of waivered physicians grew significantly over the two-year period. Rates of growth were significantly lower in ACA-hybrid and ACA-resistant states relative to growth in ACA-supportive states. Average buprenorphine physician supply at baseline varied by region, the percentage of residents covered by Medicaid, and the supply of specialty SUD treatment programs.

CONCLUSIONS

This study found a positive impact of the ACA on growth in the supply of buprenorphine-waivered physicians in US states. Future research should address whether the ACA affects the number of patients receiving buprenorphine, Medicaid spending, and the quality of treatment services delivered.

To Be Free and Normal: Addiction, Governance, and the Therapeutics of Buprenorphine

Methadone maintenance has dominated opiate addiction treatment in the United States for decades. Since 2002, opiate addiction has also been treated in general medical settings with a substance called buprenorphine. Based on interviews and participant observation conducted in northern California, this article analyzes how discourses of freedom and normalcy in patient and provider narratives reflect and affect experiences with this treatment modality. I discuss how buprenorphine treatment, in contrast to methadone maintenance, offers patients and providers a greater sense of autonomy and flexibility in how they receive and deliver treatment. It presents them with new obligations, responsibilities, and choices around care and conduct. It simultaneously perpetuates and shapes a desire to be "free" and "normal." I argue that the therapeutics of buprenorphine govern patients and providers through this desire for freedom and normalcy. Buprenorphine is thus a technology of governmentality that extends neoliberal discourses and values and produces self-governing subjects.

Buprenorphine maintenance and mu-opioid receptor availability in the treatment of opioid use disorder: implications for clinical use and policy

BACKGROUND

Sublingual formulations of buprenorphine (BUP) and BUP/naloxone have well-established pharmacokinetic and pharmacodynamic profiles, and are safe and effective for treating opioid use disorder. Since approvals of these formulations, their clinical use has increased. Yet, questions have arisen as to how BUP binding to mu-opioid receptors (μORs), the neurobiological target for this medication, relate to its clinical application. BUP produces dose- and time-related alterations of μOR availability but some clinicians express concern about whether doses higher than those needed to prevent opioid withdrawal symptoms are warranted, and policymakers consider limiting reimbursement for certain BUP dosing regimens.

METHODS

We review scientific data concerning BUP-induced changes in μOR availability and their relationship to clinical efficacy.

RESULTS

Withdrawal suppression appears to require ≤50% μOR availability, associated with BUP trough plasma concentrations ≥1 ng/mL; for most patients, this may require single daily BUP doses of 4 mg to defend against trough levels, or lower divided doses. Blockade of the reinforcing and subjective effects of typical doses of abused opioids require <20% μOR availability, associated with BUP trough plasma concentrations ≥3 ng/mL; for most individuals, this may require single daily BUP doses >16 mg, or lower divided doses. For individuals attempting to surmount this blockade with higher-than-usual doses of abused opioids, even larger BUP doses and <10% μOR availability would be required.

CONCLUSION

For these reasons, and given the complexities of studies on this issue and comorbid problems, we conclude that fixed, arbitrary limits on BUP doses in clinical care or limits on reimbursement for this care are unwarranted.

Financial factors and the implementation of medications for treating opioid use disorders

OBJECTIVES

Despite the established effectiveness of pharmacotherapies for treating opioid use disorders, implementation of medications for addiction treatment (MAT) by specialty treatment programs is limited. This research examined relationships between organizational factors and the program-level implementation of MAT, with attention paid to specific sources of funding, organizational structure, and workforce resources.

METHODS

Face-to-face structured interviews were conducted in 2008 to 2009 with administrators of 154 community-based treatment programs affiliated with the National Institute on Drug Abuse's Clinical Trials Network; none of these programs exclusively dispensed methadone without offering other levels of care. Implementation of MAT was measured by summing the percentages of opioid patients receiving buprenorphine maintenance, methadone maintenance, and tablet naltrexone. Financial factors included the percentages of revenues received from Medicaid, private insurance, criminal justice, the Federal block grant, state government, and county government. Organizational structure and workforce characteristics were also measured.

RESULTS

Implementation of MAT for opioid use disorders was low. Greater reliance on Medicaid was positively associated with implementation after controlling for organizational structure and workforce measures, whereas the association for reliance on criminal justice revenues was negative.

CONCLUSIONS

The implementation of MAT for opioid use disorders by specialty addiction treatment programs may be facilitated by Medicaid but may be impeded by reliance on funding from the criminal justice system. These findings point to the need for additional research that considers the impact of organizational dependence on different types of funding on patterns of addiction treatment practice.

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.

Prescription opioid abuse, chronic pain, and primary care: a Co-occurring Disorders Clinic in the chronic disease model

Abuse of opioids has become a public health crisis. The historic separation between the addiction and pain communities and a lack of training in medical education have made treatment difficult to provide, especially in primary care. The Co-occurring Disorders Clinic (COD) was established to treat patients with co-morbid chronic pain and addiction. This retrospective chart review reports results of a quality improvement project using buprenorphine/naloxone to treat co-occurring chronic non-cancer pain (CNCP) and opioid dependence in a primary care setting. Data were collected for 143 patients who were induced with buprenorphine/naloxone (BUP/NLX) between June 2009 and November 2011. Ninety-three patients (65%) continued to be maintained on the medication and seven completed treatment and were no longer taking any opioid (5%). Pain scores showed a modest, but statistically significant improvement on BUP/NLX, which was contrary to our expectations and may be an important factor in treatment retention for this challenging population.

Health-related quality of life changes associated with buprenorphine treatment for opioid dependence

BACKGROUND

Few studies have described improvement in health-related quality of life (HRQOL) associated with opioid dependence treatment with buprenorphine (ODT-B).

OBJECTIVE

To evaluate HRQOL changes in domain scores, physical and mental component summaries, and health utilities (HUs) associated with ODT-B using the Short Form 36 (SF-36).

METHODS

We assessed HRQOL changes in a substudy of a pharmacokinetic study that compared buprenorphine oral tablet and liquid dosage formulations over 16 weeks. Individuals, aged 18-65 years, were screened for opioid dependence. They were excluded if they would not agree to birth control or had a serious medical condition. Subjects received psychosocial counseling and weekly group therapy. The SF-36 was administered upon enrollment and at 4-week intervals. We used the SF-6D to estimate HUs. We performed intention to treat (ITT) analyses based on the last observation available for each subject. Paired t tests of each domain and HU, limited to remaining patients at each 4-week interval, were also conducted.

RESULTS

Of 96 subjects enrolled, cumulative dropouts over time resulted in 80, 69, 59, and 44 subjects remaining at 4, 8, 12, and 16 weeks. There were no significant differences in opioid-positive urines, dropout rates, or dosage changes between formulations. In the ITT analyses, HRQOL improvements over time were bodily pain (62.1 vs. 69.1, P = 0.017), vitality (49.8 vs. 56.5, P = 0.001), mental health (59.9 vs. 66.0, P = 0.001), social function (66.4 vs. 74.7, P = 0.001), role emotional (59.4 vs. 71.9, P = 0.003), role physical (60.9 vs. 70.6, P = 0.005), and mental component summary (41.9 vs. 45.4, P<0.001). HU scores also improved (0.674 vs. 0.715, P = 0.001). Results from paired t tests, with only concurrently enrolled patients, showed similar improvements from baseline to 4, 8, 12, or 16 weeks.

CONCLUSION

Buprenorphine, accompanied with psychosocial counseling, was associated with improved HRQOL and HUs.

Timing of buprenorphine adoption by privately funded substance abuse treatment programs: the role of institutional and resource-based interorganizational linkages

Identifying facilitators of more rapid buprenorphine adoption may increase access to this effective treatment for opioid dependence. Using a diffusion of innovations theoretical framework, we examine the extent to which programs' interorganizational institutional and resource-based linkages predict the likelihood of being an earlier adopter, later adopter, or nonadopter of buprenorphine. Data were derived from face-to-face interviews with administrators of 345 privately funded substance abuse treatment programs in 2007-2008. Results of multinomial logistic regression models show that interorganizational and resource linkages were associated with timing of adoption. Programs reporting membership in provider associations were more likely to be earlier adopters of buprenorphine. Programs that relied more on resource linkages, such as detailing activities by pharmaceutical companies and the National Institute on Drug Abuse website, were more likely to be earlier adopters of buprenorphine. These findings suggest that institutional and resource-based interorganizational linkages may expose programs to effective treatments, thereby facilitating more rapid and sustained adoption of innovative treatment techniques.

Diversion and abuse of buprenorphine: findings from national surveys of treatment patients and physicians

BACKGROUND

Since 2003, buprenorphine has been approved for the treatment of opioid dependence in office-based practice. Diversion and abuse can be a threat to its continued approval under these conditions.

METHODS

As part of a national postmarketing surveillance program, applicants to substance abuse treatment and physicians certified to prescribe buprenorphine were surveyed about their perceptions of buprenorphine/naloxone diversion and abuse. These surveys were supplemented by information from national databases. Availability of buprenorphine/naloxone was measured by number of tablets dispensed.

RESULTS

Measures of diversion and abuse of buprenorphine/naloxone increased from 2005 to 2009. The results from the applicant survey showed that the perceptions of the extent of diversion and abuse were lower than positive controls, methadone, oxycodone and heroin, but higher than the negative control, amitriptyline. By 2009, 46% of the physicians believed that buprenorphine/naloxone was diverted but 44% believed illegal use was for self-management of withdrawal and 53% believed the source of the medication was substance abuse patients. Other measures from national databases showed similar results. When adjusted for millions of tablets sold per year, slopes for measures of diversion and abuse were reduced.

CONCLUSIONS

The increases in diversion and abuse measures indicate the need to take active attempts to curb diversion and abuse as well as continuous monitoring and surveillance of all buprenorphine products. However, these increases parallel the increased number of tablets sold. Finding a balance of risk/benefit (i.e. diversion and abuse versus expanded treatment) remains a challenge.

Participant characteristics and buprenorphine dose

BACKGROUND

Clinical parameters for determining buprenorphine dose have not been adequately examined in treatment outcome research.

OBJECTIVES

This study is a secondary analysis of data collected in a recently completed comparison of buprenorphine taper schedules conducted as part of the National Institute on Drug Abuse's Clinical Trials Network to assess whether participant baseline characteristics are associated with buprenorphine dose.

METHODS

After 3 weeks of flexible dosing, 516 participants were categorized by dose provided in the final dosing week (9.3% received a final week dose of 8 mg buprenorphine, 27.3% received 16 mg, and 63.4% received 24 mg).

RESULTS

Findings show that final week dose groups differed in baseline demographic and drug use characteristics including education, heroin use, route of drug administration, withdrawal symptoms, and craving. These groups also differed in opioid use during the four dosing weeks, with the lowest use in the 8 mg group and highest use in the 24 mg group (p < .0001). Additional analyses address withdrawal symptoms and craving.

CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE

Final week dose groups differed in demographic and drug use characteristics, and the group receiving the largest final week dose had the highest rate of continued opioid use. These findings may contribute to the development of clinical guidelines regarding buprenorphine dose in the treatment of opioid dependence; however, further investigations that include random assignment to dose by baseline characteristics are needed.

Gender and racial/ethnic differences in addiction severity, HIV risk, and quality of life among adults in opioid detoxification: results from the National Drug Abuse Treatment Clinical Trials Network

PURPOSE: Detoxification often serves as an initial contact for treatment and represents an opportunity for engaging patients in aftercare to prevent relapse. However, there is limited information concerning clinical profiles of individuals seeking detoxification, and the opportunity to engage patients in detoxification for aftercare often is missed. This study examined clinical profiles of a geographically diverse sample of opioid-dependent adults in detoxification to discern the treatment needs of a growing number of women and whites with opioid addiction and to inform interventions aimed at improving use of aftercare or rehabilitation. METHODS: The sample included 343 opioid-dependent patients enrolled in two national multi-site studies of the National Drug Abuse Treatment Clinical Trials Network (CTN001-002). Patients were recruited from 12 addiction treatment programs across the nation. Gender and racial/ethnic differences in addiction severity, human immunodeficiency virus (HIV) risk, and quality of life were examined. RESULTS: Women and whites were more likely than men and African Americans to have greater psychiatric and family/social relationship problems and report poorer health-related quality of life and functioning. Whites and Hispanics exhibited higher levels of total HIV risk scores and risky injection drug use scores than African Americans, and Hispanics showed a higher level of unprotected sexual behaviors than whites. African Americans were more likely than whites to use heroin and cocaine and to have more severe alcohol and employment problems. CONCLUSIONS: Women and whites show more psychopathology than men and African Americans. These results highlight the need to monitor an increased trend of opioid addiction among women and whites and to develop effective combined psychosocial and pharmacologic treatments to meet the diverse needs of the expanding opioid-abusing population. Elevated levels of HIV risk behaviors among Hispanics and whites also warrant more research to delineate mechanisms and to reduce their risky behaviors.

Diversion of buprenorphine/naloxone coformulated tablets in a region with high prescribing prevalence

The purpose of this article was to characterize practices of buprenorphine/naloxone (B/N) diversion in a region with a high prescribing prevalence. A cross-sectional, open-ended survey was administered to individuals entering opioid addiction treatment programs in two New England states. The authors obtained formative information about the knowledge, attitudes, beliefs, practices, and street economy of B/N diversion. The authors interviewed 51 individuals, 49 of which were aware of B/N medication. Of that number, 100% had diverted B/N to modulate opiate withdrawal symptoms arising from attempted "self-detoxification," insufficient funds to purchase preferred illicit opioids, or inability to find a preferred source of drugs. Thirty of 49 (61%) participants obtained the illicit drug from an individual holding a legitimate prescription for B/N. A high proportion of individuals in the study locations who sought treatment for opioid addiction self-reported the purchase and use of diverted B/N. The diversion of B/N may be minimized by modifying educational, treatment, monitoring, and dispensing practices.

Buprenorphine Maintenance Therapy Hinders Acute Pain Management in Trauma

Buprenorphine is a mixed opiate receptor agonist-antagonist growing in popularity as an office-based treatment for opioid-dependent patients. It has high affinity, but only partial agonism at the μ-opioid receptor resulting in a ceiling analgesic effect. At higher doses, buprenorphine potentiates antagonism at the κ-opioid receptor. These properties make buprenorphine an effective maintenance treatment for opioid-dependent patients. These same properties, however, can interfere with the management of acute pain in patients on maintenance buprenorphine therapy. We present a case of a young multisystem trauma patient in whom adequate analgesia could not be achieved due to buprenorphine treatment before and through the early course of admission. Discontinuation of buprenorphine allowed for appropriate pain management and successful analgesia. Further education of acute care clinicians about buprenorphine pharmacology and careful selection of patients for buprenorphine maintenance therapy are needed to avoid delays of pain control in trauma patients.

Buprenorphine for opioid dependence

As a treatment agent for opioid dependence, buprenorphine is a nearly ideal medication at our current stage of medication development. Unlike methadone, buprenorphine dosage can be rapidly adjusted with minimal potential for inducing severe consequences. In addition to its intrinsic safety, buprenorphine's relatively low abuse liability in the combination product (i.e., with naloxone as Suboxone) makes it even more acceptable in regulatory quarters as well as to prescribing physicians. The approval of buprenorphine as a pharmacotherapy for opioid dependence returns to physicians the ability to treat their opioid-dependent patients with an effective opioid-based treatment for the first time in nearly 100 years. Buprenorphine is an opioid, however, and potential for misuse remains, even in combination with naloxone. Whether buprenorphine will be increasingly accepted as a treatment for opioid-dependent patients depends on clinicians recognizing the advantages of its uniquely useful properties while still heeding the need to manage their patients' therapy with reasonable vigilance.

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.

Hepatitis infection in the treatment of opioid dependence and abuse

Many new and existing cases of viral hepatitis infections are related to injection drug use. Transmission of these infections can result directly from the use of injection equipment that is contaminated with blood containing the hepatitis B or C virus or through sexual contact with an infected individual. In the latter case, drug use can indirectly contribute to hepatitis transmission through the dis-inhibited at-risk behavior, that is, unprotected sex with an infected partner. Individuals who inject drugs are at-risk for infection from different hepatitis viruses, hepatitis A, B, or C. Those with chronic hepatitis B virus infection also face additional risk should they become co-infected with hepatitis D virus. Protection from the transmission of hepatitis viruses A and B is best achieved by vaccination. For those with a history of or who currently inject drugs, the medical management of viral hepatitis infection comprising screening, testing, counseling and providing care and treatment is evolving. Components of the medical management of hepatitis infection, for persons considering, initiating, or receiving pharmacologic therapy for opioid addiction include: testing for hepatitis B and C infections; education and counseling regarding at-risk behavior and hepatitis transmission, acute and chronic hepatitis infection, liver disease and its care and treatment; vaccination against hepatitis A and B infection; and integrative primary care as part of the comprehensive treatment approach for recovery from opioid abuse and dependence. In addition, participation in a peer support group as part of integrated medical care enhances treatment outcomes. Liver disease is highly prevalent in patient populations seeking recovery from opioid addiction or who are currently receiving pharmacotherapy for opioid addiction. Pharmacotherapy for opioid addiction is not a contraindication to evaluation, care, or treatment of liver disease due to hepatitis virus infection. Successful pharmacotherapy for opioid addiction stabilizes patients and improves patient compliance to care and treatment regimens as well as promotes good patient outcomes. Implementation and integration of effective hepatitis prevention programs, care programs, and treatment regimens in concert with the pharmacological therapy of opioid addiction can reduce the public health burdens of hepatitis and injection drug use.

Well-being, psychosocial factors, and side-effects among heroin-dependent inpatients after detoxification using buprenorphine versus clonidine

Previous studies comparing buprenorphine and clonidine provided little information about subjective factors associated with the effective management of opioid withdrawal. This study sought to compare detoxification programs using these medications with regard to side-effects and related distress, general well-being, perceived self-efficacy and social support. A total of 200 treatment-seeking heroin-dependent patients, aged 18-50, were randomly assigned to buprenorphine or clonidine inpatient withdrawal treatments over 10days followed by 11days of relapse prevention measures. A semi-structured interview and a battery of self-rating scales assessing parameters of the interest were administered to the patients who completed the 10-day detoxification protocol with buprenorphine (n=90) and clonidine (n=50). Chi-square statistics and analysis of covariance were performed to examine between-group differences. Compared with patients treated with clonidine, patients who received buprenorphine developed significantly less side-effects and related distress, and had higher senses of well-being, self-efficacy and social support. The findings suggest that buprenorphine is preferable for inpatient detoxification due to its side-effects profile and positive effects on well-being and psychosocial variables. These early benefits of buprenorphine could enable consequent maintenance treatment.

Early adoption of buprenorphine in substance abuse treatment centers: data from the private and public sectors

The recent approval of buprenorphine for the treatment of opiate dependence offers an opportunity to analyze innovation adoption in community-based treatment. Using data collected from national samples of 299 privately funded and 277 publicly funded treatment centers, this research examines buprenorphine adoption using baseline data collected between 2002 and 2004 as well as follow-up data collected 12 months later. Private centers were significantly more likely than public centers to report current use of buprenorphine. The baseline data indicated that early adoption was positively associated with center accreditation, physician services, availability of detoxification services, current use of naltrexone, and the percentage of opiate-dependent clients. Multivariate analyses of follow-up data suggest that adoption was greater in accredited centers, for-profit facilities, organizations offering detoxification services, and naltrexone-using centers. Future research should continue to monitor the extent to which buprenorphine is adopted in these settings.

Prescription naloxone: a novel approach to heroin overdose prevention

The mortality and morbidity from heroin overdose have increased in the United States and internationally in the last decade. The lipid solubility allows the rapid deposition of heroin and its metabolites into the central nervous system and accounts for the "rush" experienced by users and for the toxicity. Risk factors for fatal and nonfatal heroin overdoses such as recent abstinence, decreased opiate tolerance, and polydrug use have been identified. Opiate substitution treatment such as methadone or buprenorphine is the only proven method of heroin overdose prevention. Death from a heroin overdose most commonly occurs 1 to 3 hours after injection at home in the company of other people. Numerous communities have taken advantage of this opportunity for treatment by implementing overdose prevention education to active heroin users, as well as prescribing naloxone for home use. Naloxone is a specific opiate antagonist without agonist properties or potential for abuse. It is inexpensive and nonscheduled and readily reverses the respiratory depression and sedation caused by heroin, as well as causing transient withdrawal symptoms. Program implementation considerations, legal ramifications, and research needs for prescription naloxone are discussed.

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.

Buprenorphine diffusion: the attitudes of substance abuse treatment counselors

In October 2002, the Food and Drug Administration approved buprenorphine for use in the treatment of opioid dependence. Successful diffusion, adoption, and implementation of this medication within the treatment field depend in part on substance abuse counselors. Using questionnaire data obtained from 2,298 counselors in community-based treatment programs in the private and public sectors between June 2002 and July 2004, we explored the diffusion of this new treatment technique. Analyses indicate that a substantial proportion of the clinical workforce is unaware of the effectiveness of buprenorphine in the treatment of opiate addiction. Several variables predicted counselors' attitudes toward buprenorphine. Predictors included receipt of buprenorphine-specific training, educational attainment, years of experience, and 12-step orientation. Implications for the diffusion of this and other emerging treatment techniques are discussed.

Integration of pharmacotherapy for opioid addiction into HIV primary care for HIV/hepatitis C virus-co-infected patients

Pharmacotherapy for substance abuse is a rapidly evolving field comprising both old and new effective treatments for substance use. Opiate agonist therapy has been shown to diminish and often eliminate opiate use. This behavior change has resulted in the reduced transmission of many infections, including HIV, hepatitis C virus (HCV), and an enhanced quality of life. For the past 35 years, the provision of opioid agonist therapy has been limited to opioid treatment programmes. Opioid treatment programmes treat approximately 200,000 of the estimated million opiate-addicted individuals in the United States. With the need to increase the number of treatment opportunities available for opioid-dependent patients, Congress passed the Drug Addiction Treatment Act of 2000, which allows for the treatment of opioid dependence using buprenorphine by a properly licensed physician, including HIV primary care physicians. The integration of buprenorphine treatment for opioid addiction into HIV primary care thus provides a new treatment paradigm to address substance abuse in patients with HIV and HCV infections.

High-dose buprenorphine: perioperative precautions and management strategies

Buprenorphine has been in clinical use in anaesthesia for several decades. Recently, the high-dose sublingual formulation (Subutex, Reckitt Benckiser, Slough, U.K.) has been increasingly used as maintenance therapy in opioid dependence, as an alternative to methadone and other pharmacological therapies. Buprenorphine has unique pharmacological properties making it well suited for use as a maintenance therapy in opioid dependence. However, these same properties may cause difficulty in the perioperative management of pain. Buprenorphine is a partial opioid agonist, attenuating the effects of supplemental illicit or therapeutic opioid agonists. As a result of its high receptor affinity, supplemental opioids do not readily displace buprenorphine from the opioid receptor in standard doses. High-dose buprenorphine has an extended duration of action that prolongs both of these effects. The perioperative management of patients stabilized on high-dose buprenorphine and undergoing surgery requires consideration of the likely analgesic requirements. Where possible the buprenorphine should be continued. Pain management should focus on maximizing non-opioid analgesia, local anaesthesia and non-pharmacological techniques. Where pain may not be adequately relieved by these methods, the addition of a full opioid agonist such as fentanyl or morphine at appropriate doses should be considered, accompanied by close monitoring in a high dependency unit. In situations where this regimen is unlikely to be effective, preoperative conversion to morphine or methadone may be an option. Where available, liaison with a hospital-based alcohol and drug service should always be considered.

Bringing buprenorphine-naloxone detoxification to community treatment providers: the NIDA Clinical Trials Network field experience

In October 2002, the U.S. Food and Drug Administration approved buprenorphine-naloxone (Suboxone) sublingual tablets as an opioid dependence treatment available for use outside traditionally licensed opioid treatment programs. The NIDA Center for Clinical Trials Network (CTN) sponsored two clinical trials assessing buprenorphine-naloxone for short-term opioid detoxification. These trials provided an unprecedented field test of its use in twelve diverse community-based treatment programs. Opioid-dependent men and women were randomized to a thirteen-day buprenorphine-naloxone taper regimen for short-term opioid detoxification. The 234 buprenorphine-naloxone patients averaged 37 years old and used mostly intravenous heroin. Direct and rapid induction onto buprenorphine-naloxone was safe and well tolerated. Most patients (83%) received 8 mg buprenorphine-2 mg naloxone on the first day and 90% successfully completed induction and reached a target dose of 16 mg buprenorphine-4 mg naloxone in three days. Medication compliance and treatment engagement was high. An average of 81% of available doses was ingested, and 68% of patients completed the detoxification. Most (80.3%) patients received some ancillary medications with an average of 2.3 withdrawal symptoms treated. The safety profile of buprenorphine-naloxone was excellent. Of eighteen serious adverse events reported, only one was possibly related to buprenorphine-naloxone. All providers successfully integrated buprenorphine-naloxone into their existing treatment milieus. Overall, data from the CTN field experience suggest that buprenorphine-naloxone is practical and safe for use in diverse community treatment settings, including those with minimal experience providing opioid-based pharmacotherapy and/or medical detoxification for opioid dependence.

Practical considerations for the clinical use of buprenorphine

Buprenorphine is a new and attractive medication option for many opioid-addicted adults and their physicians. Before initiating buprenorphine treatment, providers must be aware of such critical factors as how the medication works, its efficacy and safety profile, how it is used in opioid withdrawal as well as maintenance treatment, and how patients can best be selected, educated about buprenorphine, and monitored throughout treatment. This article reviews these important issues as well as requirements for physician and staff training and needs for additional research on this unique medication.